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* [PATCH 0/2] iio: accel: Add support for ADXL313 accelerometer
@ 2021-07-31 20:36 Lucas Stankus
  2021-07-31 20:36 ` [PATCH 1/2] dt-bindings: iio: accel: Add binding documentation for ADXL313 Lucas Stankus
  2021-07-31 20:36 ` [PATCH 2/2] iio: accel: Add driver support " Lucas Stankus
  0 siblings, 2 replies; 14+ messages in thread
From: Lucas Stankus @ 2021-07-31 20:36 UTC (permalink / raw)
  To: lars, Michael.Hennerich, jic23, robh+dt, Dragos.Bogdan, Darius.Berghe
  Cc: linux-iio, devicetree, linux-kernel

Add driver support and dt-bindings documentation for ADXL313 digital
accelerometer.

Lucas Stankus (2):
  dt-bindings: iio: accel: Add binding documentation for ADXL313
  iio: accel: Add driver support for ADXL313

 .../bindings/iio/accel/adi,adxl313.yaml       |  75 ++++
 MAINTAINERS                                   |   9 +
 drivers/iio/accel/Kconfig                     |  29 ++
 drivers/iio/accel/Makefile                    |   3 +
 drivers/iio/accel/adxl313.h                   |  60 ++++
 drivers/iio/accel/adxl313_core.c              | 323 ++++++++++++++++++
 drivers/iio/accel/adxl313_i2c.c               |  65 ++++
 drivers/iio/accel/adxl313_spi.c               |  74 ++++
 8 files changed, 638 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
 create mode 100644 drivers/iio/accel/adxl313.h
 create mode 100644 drivers/iio/accel/adxl313_core.c
 create mode 100644 drivers/iio/accel/adxl313_i2c.c
 create mode 100644 drivers/iio/accel/adxl313_spi.c

-- 
2.32.0


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH 1/2] dt-bindings: iio: accel: Add binding documentation for ADXL313
  2021-07-31 20:36 [PATCH 0/2] iio: accel: Add support for ADXL313 accelerometer Lucas Stankus
@ 2021-07-31 20:36 ` Lucas Stankus
  2021-08-01 18:04   ` Jonathan Cameron
  2021-08-02 13:39   ` Rob Herring
  2021-07-31 20:36 ` [PATCH 2/2] iio: accel: Add driver support " Lucas Stankus
  1 sibling, 2 replies; 14+ messages in thread
From: Lucas Stankus @ 2021-07-31 20:36 UTC (permalink / raw)
  To: lars, Michael.Hennerich, jic23, robh+dt, Dragos.Bogdan, Darius.Berghe
  Cc: linux-iio, devicetree, linux-kernel

Add device tree binding documentation for ADXL313 3-axis accelerometer.

Signed-off-by: Lucas Stankus <lucas.p.stankus@gmail.com>
---
 .../bindings/iio/accel/adi,adxl313.yaml       | 75 +++++++++++++++++++
 1 file changed, 75 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml

diff --git a/Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml b/Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
new file mode 100644
index 000000000000..31f11d7eaaae
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
@@ -0,0 +1,75 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/accel/adi,adxl313.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Analog Devices ADXL313 3-Axis Digital Accelerometer
+
+maintainers:
+  - Lucas Stankus <lucas.p.stankus@gmail.com>
+
+description: |
+  Analog Devices ADXL313 3-Axis Digital Accelerometer that supports
+  both I2C & SPI interfaces.
+    https://www.analog.com/en/products/adxl313.html
+
+properties:
+  compatible:
+    enum:
+      - adi,adxl313
+
+  reg:
+    maxItems: 1
+
+  spi-3wire: true
+
+  spi-cpha: true
+
+  spi-cpol: true
+
+  spi-max-frequency: true
+
+  interrupts:
+    maxItems: 2
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+    i2c0 {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        /* Example for a I2C device node */
+        accelerometer@53 {
+            compatible = "adi,adxl313";
+            reg = <0x53>;
+            interrupt-parent = <&gpio0>;
+            interrupts = <0 IRQ_TYPE_LEVEL_HIGH>;
+        };
+    };
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+    spi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        /* Example for a SPI device node */
+        accelerometer@0 {
+            compatible = "adi,adxl313";
+            reg = <0>;
+            spi-max-frequency = <5000000>;
+            spi-cpol;
+            spi-cpha;
+            interrupt-parent = <&gpio0>;
+            interrupts = <0 IRQ_TYPE_LEVEL_HIGH>;
+        };
+    };
-- 
2.32.0


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH 2/2] iio: accel: Add driver support for ADXL313
  2021-07-31 20:36 [PATCH 0/2] iio: accel: Add support for ADXL313 accelerometer Lucas Stankus
  2021-07-31 20:36 ` [PATCH 1/2] dt-bindings: iio: accel: Add binding documentation for ADXL313 Lucas Stankus
@ 2021-07-31 20:36 ` Lucas Stankus
  2021-08-01 18:12   ` Jonathan Cameron
  2021-08-02  7:04   ` Alexandru Ardelean
  1 sibling, 2 replies; 14+ messages in thread
From: Lucas Stankus @ 2021-07-31 20:36 UTC (permalink / raw)
  To: lars, Michael.Hennerich, jic23, robh+dt, Dragos.Bogdan, Darius.Berghe
  Cc: linux-iio, devicetree, linux-kernel

ADXL313 is a small, thin, low power, 3-axis accelerometer with high
resolution measurement up to +/-4g. It includes an integrated 32-level
FIFO and has activity and inactivity sensing capabilities.

Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf

Signed-off-by: Lucas Stankus <lucas.p.stankus@gmail.com>
---
 MAINTAINERS                      |   9 +
 drivers/iio/accel/Kconfig        |  29 +++
 drivers/iio/accel/Makefile       |   3 +
 drivers/iio/accel/adxl313.h      |  60 ++++++
 drivers/iio/accel/adxl313_core.c | 323 +++++++++++++++++++++++++++++++
 drivers/iio/accel/adxl313_i2c.c  |  65 +++++++
 drivers/iio/accel/adxl313_spi.c  |  74 +++++++
 7 files changed, 563 insertions(+)
 create mode 100644 drivers/iio/accel/adxl313.h
 create mode 100644 drivers/iio/accel/adxl313_core.c
 create mode 100644 drivers/iio/accel/adxl313_i2c.c
 create mode 100644 drivers/iio/accel/adxl313_spi.c

diff --git a/MAINTAINERS b/MAINTAINERS
index a61f4f3b78a9..1fc88723e632 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -585,6 +585,15 @@ L:	platform-driver-x86@vger.kernel.org
 S:	Maintained
 F:	drivers/platform/x86/adv_swbutton.c
 
+ADXL313 THREE-AXIS DIGITAL ACCELEROMETER DRIVER
+M:	Lucas Stankus <lucas.p.stankus@gmail.com>
+S:	Supported
+F:	Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
+F:	drivers/iio/accel/adxl313.h
+F:	drivers/iio/accel/adxl313_core.c
+F:	drivers/iio/accel/adxl313_i2c.c
+F:	drivers/iio/accel/adxl313_spi.c
+
 ADXL34X THREE-AXIS DIGITAL ACCELEROMETER DRIVER (ADXL345/ADXL346)
 M:	Michael Hennerich <michael.hennerich@analog.com>
 S:	Supported
diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
index 0e56ace61103..ae621532e716 100644
--- a/drivers/iio/accel/Kconfig
+++ b/drivers/iio/accel/Kconfig
@@ -30,6 +30,35 @@ config ADIS16209
 	  To compile this driver as a module, say M here: the module will be
 	  called adis16209.
 
+config ADXL313
+	tristate
+
+config ADXL313_I2C
+	tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer I2C Driver"
+	depends on I2C
+	select ADXL313
+	select REGMAP_I2C
+	help
+	  Say Y here if you want to build i2c support for the Analog Devices
+	  ADXL313 3-axis digital accelerometer.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called adxl313_i2c and you will also get adxl313_core
+	  for the core module.
+
+config ADXL313_SPI
+	tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer SPI Driver"
+	depends on SPI
+	select ADXL313
+	select REGMAP_SPI
+	help
+	  Say Y here if you want to build spi support for the Analog Devices
+	  ADXL313 3-axis digital accelerometer.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called adxl313_spi and you will also get adxl313_core
+	  for the core module.
+
 config ADXL345
 	tristate
 
diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
index 89280e823bcd..fadc92816e24 100644
--- a/drivers/iio/accel/Makefile
+++ b/drivers/iio/accel/Makefile
@@ -6,6 +6,9 @@
 # When adding new entries keep the list in alphabetical order
 obj-$(CONFIG_ADIS16201) += adis16201.o
 obj-$(CONFIG_ADIS16209) += adis16209.o
+obj-$(CONFIG_ADXL313) += adxl313_core.o
+obj-$(CONFIG_ADXL313_I2C) += adxl313_i2c.o
+obj-$(CONFIG_ADXL313_SPI) += adxl313_spi.o
 obj-$(CONFIG_ADXL345) += adxl345_core.o
 obj-$(CONFIG_ADXL345_I2C) += adxl345_i2c.o
 obj-$(CONFIG_ADXL345_SPI) += adxl345_spi.o
diff --git a/drivers/iio/accel/adxl313.h b/drivers/iio/accel/adxl313.h
new file mode 100644
index 000000000000..72f268e02a80
--- /dev/null
+++ b/drivers/iio/accel/adxl313.h
@@ -0,0 +1,60 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * ADXL313 3-Axis Digital Accelerometer
+ *
+ * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
+ */
+
+#ifndef _ADXL313_H_
+#define _ADXL313_H_
+
+/* ADXL313 register definitions */
+#define ADXL313_REG_DEVID0		0x00
+#define ADXL313_REG_DEVID1		0x01
+#define ADXL313_REG_PARTID		0x02
+#define ADXL313_REG_XID			0x04
+#define ADXL313_REG_SOFT_RESET		0x18
+#define ADXL313_REG_OFS_AXIS(index)	(0x1E + (index))
+#define ADXL313_REG_THRESH_ACT		0x24
+#define ADXL313_REG_ACT_INACT_CTL	0x27
+#define ADXL313_REG_BW_RATE		0x2C
+#define ADXL313_REG_POWER_CTL		0x2D
+#define ADXL313_REG_INT_MAP		0x2F
+#define ADXL313_REG_DATA_FORMAT		0x31
+#define ADXL313_REG_DATAX		0x32
+#define ADXL313_REG_DATAY		0x34
+#define ADXL313_REG_DATAZ		0x36
+#define ADXL313_REG_FIFO_CTL		0x38
+#define ADXL313_REG_FIFO_STATUS		0x39
+
+#define ADXL313_DEVID0			0xAD
+#define ADXL313_DEVID1			0x1D
+#define ADXL313_PARTID			0xCB
+#define ADXL313_SOFT_RESET		0x52
+
+#define ADXL313_RATE_MSK		GENMASK(3, 0)
+#define ADXL313_RATE_BASE		6
+
+#define ADXL313_POWER_CTL_MSK		GENMASK(3, 2)
+#define ADXL313_MEASUREMENT_MODE	BIT(3)
+
+#define ADXL313_RANGE_MSK		GENMASK(1, 0)
+#define ADXL313_RANGE_4G		3
+
+#define ADXL313_FULL_RES		BIT(3)
+#define ADXL313_SPI_3WIRE		BIT(6)
+#define ADXL313_I2C_DISABLE		BIT(6)
+
+/*
+ * Scale for any g range is given in datasheet as
+ * 1024 LSB/g = 0.0009765625 * 9.80665 = 0.009576806640625 m/s^2
+ */
+#define ADXL313_NSCALE 9576806
+
+extern const struct regmap_access_table adxl313_readable_regs_table;
+
+extern const struct regmap_access_table adxl313_writable_regs_table;
+
+int adxl313_core_probe(struct device *dev, struct regmap *regmap,
+		       const char *name);
+#endif /* _ADXL313_H_ */
diff --git a/drivers/iio/accel/adxl313_core.c b/drivers/iio/accel/adxl313_core.c
new file mode 100644
index 000000000000..76382ab4f0f4
--- /dev/null
+++ b/drivers/iio/accel/adxl313_core.c
@@ -0,0 +1,323 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ADXL313 3-Axis Digital Accelerometer
+ *
+ * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
+ *
+ * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
+ */
+
+#include <linux/bitfield.h>
+#include <linux/iio/iio.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+
+#include "adxl313.h"
+
+const struct regmap_range adxl313_readable_reg_range[] = {
+	regmap_reg_range(ADXL313_REG_DEVID0, ADXL313_REG_XID),
+	regmap_reg_range(ADXL313_REG_SOFT_RESET, ADXL313_REG_SOFT_RESET),
+	regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
+	regmap_reg_range(ADXL313_REG_THRESH_ACT, ADXL313_REG_ACT_INACT_CTL),
+	regmap_reg_range(ADXL313_REG_BW_RATE, ADXL313_REG_FIFO_STATUS)
+};
+
+const struct regmap_access_table adxl313_readable_regs_table = {
+	.yes_ranges = adxl313_readable_reg_range,
+	.n_yes_ranges = ARRAY_SIZE(adxl313_readable_reg_range)
+};
+EXPORT_SYMBOL_GPL(adxl313_readable_regs_table);
+
+const struct regmap_range adxl313_writable_reg_range[] = {
+	regmap_reg_range(ADXL313_REG_SOFT_RESET, ADXL313_REG_SOFT_RESET),
+	regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
+	regmap_reg_range(ADXL313_REG_THRESH_ACT, ADXL313_REG_ACT_INACT_CTL),
+	regmap_reg_range(ADXL313_REG_BW_RATE, ADXL313_REG_INT_MAP),
+	regmap_reg_range(ADXL313_REG_DATA_FORMAT, ADXL313_REG_DATA_FORMAT),
+	regmap_reg_range(ADXL313_REG_FIFO_CTL, ADXL313_REG_FIFO_CTL)
+};
+
+const struct regmap_access_table adxl313_writable_regs_table = {
+	.yes_ranges = adxl313_writable_reg_range,
+	.n_yes_ranges = ARRAY_SIZE(adxl313_writable_reg_range)
+};
+EXPORT_SYMBOL_GPL(adxl313_writable_regs_table);
+
+struct adxl313_data {
+	struct regmap	*regmap;
+	struct mutex	lock; /* lock to protect transf_buf */
+	__le16		transf_buf ____cacheline_aligned;
+};
+
+static const int adxl313_odr_freqs[][2] = {
+	[0] = { 6, 250000 },
+	[1] = { 12, 500000 },
+	[2] = { 25, 0 },
+	[3] = { 50, 0 },
+	[4] = { 100, 0 },
+	[5] = { 200, 0 },
+	[6] = { 400, 0 },
+	[7] = { 800, 0 },
+	[8] = { 1600, 0 },
+	[9] = { 3200, 0 },
+};
+
+#define ADXL313_ACCEL_CHANNEL(index, addr, axis) {			\
+	.type = IIO_ACCEL,						\
+	.address = addr,						\
+	.modified = 1,							\
+	.channel2 = IIO_MOD_##axis,					\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\
+			      BIT(IIO_CHAN_INFO_CALIBBIAS),		\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |		\
+				    BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
+	.info_mask_shared_by_type_available =				\
+		BIT(IIO_CHAN_INFO_SAMP_FREQ),				\
+	.scan_index = index,						\
+	.scan_type = {							\
+		.sign = 's',						\
+		.realbits = 13,						\
+		.storagebits = 16,					\
+		.endianness = IIO_LE,					\
+	},								\
+}
+
+static const struct iio_chan_spec adxl313_channels[] = {
+	ADXL313_ACCEL_CHANNEL(0, ADXL313_REG_DATAX, X),
+	ADXL313_ACCEL_CHANNEL(1, ADXL313_REG_DATAY, Y),
+	ADXL313_ACCEL_CHANNEL(2, ADXL313_REG_DATAZ, Z),
+};
+
+static int adxl313_set_odr(struct adxl313_data *data,
+			   unsigned int freq1, unsigned int freq2)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(adxl313_odr_freqs); i++) {
+		if (adxl313_odr_freqs[i][0] == freq1 &&
+		    adxl313_odr_freqs[i][1] == freq2)
+			break;
+	}
+
+	if (i == ARRAY_SIZE(adxl313_odr_freqs))
+		return -EINVAL;
+
+	return regmap_update_bits(data->regmap, ADXL313_REG_BW_RATE,
+				  ADXL313_RATE_MSK,
+				  FIELD_PREP(ADXL313_RATE_MSK,
+					     ADXL313_RATE_BASE + i));
+}
+
+static int adxl313_read_axis(struct adxl313_data *data,
+			     struct iio_chan_spec const *chan)
+{
+	int ret;
+
+	mutex_lock(&data->lock);
+
+	ret = regmap_bulk_read(data->regmap,
+			       chan->address,
+			       &data->transf_buf, 2);
+	if (ret)
+		goto unlock_ret;
+
+	ret = le16_to_cpu(data->transf_buf);
+
+unlock_ret:
+	mutex_unlock(&data->lock);
+	return ret;
+}
+
+static int adxl313_read_freq_avail(struct iio_dev *indio_dev,
+				   struct iio_chan_spec const *chan,
+				   const int **vals, int *type, int *length,
+				   long mask)
+{
+	switch (mask) {
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		*vals = (const int *)adxl313_odr_freqs;
+		*length = ARRAY_SIZE(adxl313_odr_freqs) * 2;
+		*type = IIO_VAL_INT_PLUS_MICRO;
+		return IIO_AVAIL_LIST;
+	}
+
+	return -EINVAL;
+}
+
+static int adxl313_read_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int *val, int *val2, long mask)
+{
+	struct adxl313_data *data = iio_priv(indio_dev);
+	unsigned int regval;
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		ret = adxl313_read_axis(data, chan);
+		if (ret < 0)
+			return ret;
+
+		*val = sign_extend32(ret, chan->scan_type.realbits - 1);
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		*val = 0;
+		*val2 = ADXL313_NSCALE;
+		return IIO_VAL_INT_PLUS_NANO;
+	case IIO_CHAN_INFO_CALIBBIAS:
+		ret = regmap_read(data->regmap,
+				  ADXL313_REG_OFS_AXIS(chan->scan_index),
+				  &regval);
+		if (ret)
+			return ret;
+
+		/*
+		 * 8-bit resolution at +/- 0.5g, that is 4x accel data scale
+		 * factor at full resolution
+		 */
+		*val = sign_extend32(regval, 7) * 4;
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		ret = regmap_read(data->regmap, ADXL313_REG_BW_RATE, &regval);
+		if (ret)
+			return ret;
+
+		ret = FIELD_GET(ADXL313_RATE_MSK, regval) - ADXL313_RATE_BASE;
+		*val = adxl313_odr_freqs[ret][0];
+		*val2 = adxl313_odr_freqs[ret][1];
+		return IIO_VAL_INT_PLUS_MICRO;
+	}
+
+	return -EINVAL;
+}
+
+static int adxl313_write_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     int val, int val2, long mask)
+{
+	struct adxl313_data *data = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_CALIBBIAS:
+		/*
+		 * 8-bit resolution at +/- 0.5g, that is 4x accel data scale
+		 * factor at full resolution
+		 */
+		if (val > 127 * 4 || val < -128 * 4)
+			return -EINVAL;
+
+		return regmap_write(data->regmap,
+				    ADXL313_REG_OFS_AXIS(chan->scan_index),
+				    val / 4);
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		return adxl313_set_odr(data, val, val2);
+	}
+
+	return -EINVAL;
+}
+
+static const struct iio_info adxl313_info = {
+	.read_raw	= adxl313_read_raw,
+	.write_raw	= adxl313_write_raw,
+	.read_avail	= adxl313_read_freq_avail
+};
+
+static int adxl313_setup(struct device *dev, struct adxl313_data *data)
+{
+	unsigned int regval;
+	int ret;
+
+	/* Ensures the device is in a consistent state after start up */
+	ret = regmap_write(data->regmap, ADXL313_REG_SOFT_RESET,
+			   ADXL313_SOFT_RESET);
+	if (ret)
+		return ret;
+
+	if (device_property_read_bool(dev, "spi-3wire")) {
+		ret = regmap_write(data->regmap, ADXL313_REG_DATA_FORMAT,
+				   ADXL313_SPI_3WIRE);
+		if (ret)
+			return ret;
+	}
+
+	ret = regmap_read(data->regmap, ADXL313_REG_DEVID0, &regval);
+	if (ret)
+		return ret;
+
+	if (regval != ADXL313_DEVID0) {
+		dev_err(dev, "Invalid manufacturer ID: 0x%02x\n", regval);
+		return -ENODEV;
+	}
+
+	ret = regmap_read(data->regmap, ADXL313_REG_DEVID1, &regval);
+	if (ret)
+		return ret;
+
+	if (regval != ADXL313_DEVID1) {
+		dev_err(dev, "Invalid mems ID: 0x%02x\n", regval);
+		return -ENODEV;
+	}
+
+	ret = regmap_read(data->regmap, ADXL313_REG_PARTID, &regval);
+	if (ret)
+		return ret;
+
+	if (regval != ADXL313_PARTID) {
+		dev_err(dev, "Invalid device ID: 0x%02x\n", regval);
+		return -ENODEV;
+	}
+
+	/* Sets the range to +/- 4g */
+	ret = regmap_update_bits(data->regmap, ADXL313_REG_DATA_FORMAT,
+				 ADXL313_RANGE_MSK,
+				 FIELD_PREP(ADXL313_RANGE_MSK,
+					    ADXL313_RANGE_4G));
+	if (ret)
+		return ret;
+
+	/* Enables full resolution */
+	ret = regmap_update_bits(data->regmap, ADXL313_REG_DATA_FORMAT,
+				 ADXL313_FULL_RES, ADXL313_FULL_RES);
+	if (ret)
+		return ret;
+
+	/* Enables measurement mode */
+	return regmap_update_bits(data->regmap, ADXL313_REG_POWER_CTL,
+				  ADXL313_POWER_CTL_MSK,
+				  ADXL313_MEASUREMENT_MODE);
+}
+
+int adxl313_core_probe(struct device *dev, struct regmap *regmap,
+		       const char *name)
+{
+	struct adxl313_data *data;
+	struct iio_dev *indio_dev;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	data = iio_priv(indio_dev);
+	data->regmap = regmap;
+	mutex_init(&data->lock);
+
+	indio_dev->name = name;
+	indio_dev->info = &adxl313_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = adxl313_channels;
+	indio_dev->num_channels = ARRAY_SIZE(adxl313_channels);
+
+	ret = adxl313_setup(dev, data);
+	if (ret) {
+		dev_err(dev, "ADXL313 setup failed\n");
+		return ret;
+	}
+
+	return devm_iio_device_register(dev, indio_dev);
+}
+EXPORT_SYMBOL_GPL(adxl313_core_probe);
+
+MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
+MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer core driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/accel/adxl313_i2c.c b/drivers/iio/accel/adxl313_i2c.c
new file mode 100644
index 000000000000..65050a2fbd38
--- /dev/null
+++ b/drivers/iio/accel/adxl313_i2c.c
@@ -0,0 +1,65 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ADXL313 3-Axis Digital Accelerometer
+ *
+ * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
+ *
+ * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
+ */
+
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+
+#include "adxl313.h"
+
+static const struct regmap_config adxl313_i2c_regmap_config = {
+	.reg_bits	= 8,
+	.val_bits	= 8,
+	.rd_table	= &adxl313_readable_regs_table,
+	.wr_table	= &adxl313_writable_regs_table,
+	.max_register	= 0x39
+};
+
+static int adxl313_i2c_probe(struct i2c_client *client)
+{
+	struct regmap *regmap;
+
+	regmap = devm_regmap_init_i2c(client, &adxl313_i2c_regmap_config);
+	if (IS_ERR(regmap)) {
+		dev_err(&client->dev, "Error initializing i2c regmap: %ld\n",
+			PTR_ERR(regmap));
+		return PTR_ERR(regmap);
+	}
+
+	return adxl313_core_probe(&client->dev, regmap, client->name);
+}
+
+static const struct i2c_device_id adxl313_i2c_id[] = {
+	{ "adxl313", 0 },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(i2c, adxl313_i2c_id);
+
+static const struct of_device_id adxl313_of_match[] = {
+	{ .compatible = "adi,adxl313" },
+	{ },
+};
+
+MODULE_DEVICE_TABLE(of, adxl313_of_match);
+
+static struct i2c_driver adxl313_i2c_driver = {
+	.driver = {
+		.name	= "adxl313_i2c",
+		.of_match_table = adxl313_of_match,
+	},
+	.probe_new	= adxl313_i2c_probe,
+	.id_table	= adxl313_i2c_id,
+};
+
+module_i2c_driver(adxl313_i2c_driver);
+
+MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
+MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer I2C driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/accel/adxl313_spi.c b/drivers/iio/accel/adxl313_spi.c
new file mode 100644
index 000000000000..7c58c9ff8985
--- /dev/null
+++ b/drivers/iio/accel/adxl313_spi.c
@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ADXL313 3-Axis Digital Accelerometer
+ *
+ * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
+ *
+ * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
+ */
+
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/spi/spi.h>
+
+#include "adxl313.h"
+
+static const struct regmap_config adxl313_spi_regmap_config = {
+	.reg_bits	= 8,
+	.val_bits	= 8,
+	.rd_table	= &adxl313_readable_regs_table,
+	.wr_table	= &adxl313_writable_regs_table,
+	.max_register	= 0x39,
+	 /* Setting bits 7 and 6 enables multiple-byte read */
+	.read_flag_mask	= BIT(7) | BIT(6)
+};
+
+static int adxl313_spi_probe(struct spi_device *spi)
+{
+	const struct spi_device_id *id = spi_get_device_id(spi);
+	struct regmap *regmap;
+	int ret;
+
+	regmap = devm_regmap_init_spi(spi, &adxl313_spi_regmap_config);
+	if (IS_ERR(regmap)) {
+		dev_err(&spi->dev, "Error initializing spi regmap: %ld\n",
+			PTR_ERR(regmap));
+		return PTR_ERR(regmap);
+	}
+
+	ret = adxl313_core_probe(&spi->dev, regmap, id->name);
+	if (ret < 0)
+		return ret;
+
+	return regmap_update_bits(regmap, ADXL313_REG_POWER_CTL,
+				  ADXL313_I2C_DISABLE, ADXL313_I2C_DISABLE);
+}
+
+static const struct spi_device_id adxl313_spi_id[] = {
+	{ "adxl313", 0 },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(spi, adxl313_spi_id);
+
+static const struct of_device_id adxl313_of_match[] = {
+	{ .compatible = "adi,adxl313" },
+	{ },
+};
+
+MODULE_DEVICE_TABLE(of, adxl313_of_match);
+
+static struct spi_driver adxl313_spi_driver = {
+	.driver = {
+		.name	= "adxl313_spi",
+		.of_match_table = adxl313_of_match,
+	},
+	.probe		= adxl313_spi_probe,
+	.id_table	= adxl313_spi_id,
+};
+
+module_spi_driver(adxl313_spi_driver);
+
+MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
+MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer SPI driver");
+MODULE_LICENSE("GPL v2");
-- 
2.32.0


^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH 1/2] dt-bindings: iio: accel: Add binding documentation for ADXL313
  2021-07-31 20:36 ` [PATCH 1/2] dt-bindings: iio: accel: Add binding documentation for ADXL313 Lucas Stankus
@ 2021-08-01 18:04   ` Jonathan Cameron
  2021-08-02 16:49     ` Lucas Stankus
  2021-08-02 13:39   ` Rob Herring
  1 sibling, 1 reply; 14+ messages in thread
From: Jonathan Cameron @ 2021-08-01 18:04 UTC (permalink / raw)
  To: Lucas Stankus
  Cc: lars, Michael.Hennerich, robh+dt, Dragos.Bogdan, Darius.Berghe,
	linux-iio, devicetree, linux-kernel

On Sat, 31 Jul 2021 17:36:31 -0300
Lucas Stankus <lucas.p.stankus@gmail.com> wrote:

> Add device tree binding documentation for ADXL313 3-axis accelerometer.
> 
> Signed-off-by: Lucas Stankus <lucas.p.stankus@gmail.com>

Hi Lucas, 

A few minor requests for additions inline, so we include everything
that is likely to be used by the driver in the longer term.

> ---
>  .../bindings/iio/accel/adi,adxl313.yaml       | 75 +++++++++++++++++++
>  1 file changed, 75 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
> 
> diff --git a/Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml b/Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
> new file mode 100644
> index 000000000000..31f11d7eaaae
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
> @@ -0,0 +1,75 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/accel/adi,adxl313.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Analog Devices ADXL313 3-Axis Digital Accelerometer
> +
> +maintainers:
> +  - Lucas Stankus <lucas.p.stankus@gmail.com>
> +
> +description: |
> +  Analog Devices ADXL313 3-Axis Digital Accelerometer that supports
> +  both I2C & SPI interfaces.
> +    https://www.analog.com/en/products/adxl313.html
> +
> +properties:
> +  compatible:
> +    enum:
> +      - adi,adxl313
> +
> +  reg:
> +    maxItems: 1
> +
> +  spi-3wire: true
> +
> +  spi-cpha: true
> +
> +  spi-cpol: true
> +
> +  spi-max-frequency: true
> +
> +  interrupts:
> +    maxItems: 2

As board designers have an annoying habit of wiring up the second
interrupt only, please also provide interrupt-names so we can
know which one is connected if it's only one.

From a quick glance at the datasheet, I see this also has two powersupplies.
Please include
vddio-supply
vs-supply - annoyingly the s just stands for supply, but v-supply seems a bit to minimal.

> +
> +required:
> +  - compatible
> +  - reg
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +    i2c0 {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        /* Example for a I2C device node */
> +        accelerometer@53 {
> +            compatible = "adi,adxl313";
> +            reg = <0x53>;
> +            interrupt-parent = <&gpio0>;
> +            interrupts = <0 IRQ_TYPE_LEVEL_HIGH>;
> +        };
> +    };
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +    spi {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        /* Example for a SPI device node */
> +        accelerometer@0 {
> +            compatible = "adi,adxl313";
> +            reg = <0>;
> +            spi-max-frequency = <5000000>;
> +            spi-cpol;
> +            spi-cpha;
> +            interrupt-parent = <&gpio0>;
> +            interrupts = <0 IRQ_TYPE_LEVEL_HIGH>;
> +        };
> +    };


^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH 2/2] iio: accel: Add driver support for ADXL313
  2021-07-31 20:36 ` [PATCH 2/2] iio: accel: Add driver support " Lucas Stankus
@ 2021-08-01 18:12   ` Jonathan Cameron
  2021-08-02  6:57     ` Alexandru Ardelean
  2021-08-02 17:15     ` Lucas Stankus
  2021-08-02  7:04   ` Alexandru Ardelean
  1 sibling, 2 replies; 14+ messages in thread
From: Jonathan Cameron @ 2021-08-01 18:12 UTC (permalink / raw)
  To: Lucas Stankus
  Cc: lars, Michael.Hennerich, robh+dt, Dragos.Bogdan, Darius.Berghe,
	linux-iio, devicetree, linux-kernel

On Sat, 31 Jul 2021 17:36:48 -0300
Lucas Stankus <lucas.p.stankus@gmail.com> wrote:

> ADXL313 is a small, thin, low power, 3-axis accelerometer with high
> resolution measurement up to +/-4g. It includes an integrated 32-level
> FIFO and has activity and inactivity sensing capabilities.
> 
> Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> 
> Signed-off-by: Lucas Stankus <lucas.p.stankus@gmail.com>

Very nice.  A few really minor things inline.

Jonathan

> ---
>  MAINTAINERS                      |   9 +
>  drivers/iio/accel/Kconfig        |  29 +++
>  drivers/iio/accel/Makefile       |   3 +
>  drivers/iio/accel/adxl313.h      |  60 ++++++
>  drivers/iio/accel/adxl313_core.c | 323 +++++++++++++++++++++++++++++++
>  drivers/iio/accel/adxl313_i2c.c  |  65 +++++++
>  drivers/iio/accel/adxl313_spi.c  |  74 +++++++
>  7 files changed, 563 insertions(+)
>  create mode 100644 drivers/iio/accel/adxl313.h
>  create mode 100644 drivers/iio/accel/adxl313_core.c
>  create mode 100644 drivers/iio/accel/adxl313_i2c.c
>  create mode 100644 drivers/iio/accel/adxl313_spi.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index a61f4f3b78a9..1fc88723e632 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -585,6 +585,15 @@ L:	platform-driver-x86@vger.kernel.org
>  S:	Maintained
>  F:	drivers/platform/x86/adv_swbutton.c
>  
> +ADXL313 THREE-AXIS DIGITAL ACCELEROMETER DRIVER
> +M:	Lucas Stankus <lucas.p.stankus@gmail.com>
> +S:	Supported
> +F:	Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
> +F:	drivers/iio/accel/adxl313.h
> +F:	drivers/iio/accel/adxl313_core.c
> +F:	drivers/iio/accel/adxl313_i2c.c
> +F:	drivers/iio/accel/adxl313_spi.c
> +
>  ADXL34X THREE-AXIS DIGITAL ACCELEROMETER DRIVER (ADXL345/ADXL346)
>  M:	Michael Hennerich <michael.hennerich@analog.com>
>  S:	Supported
> diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
> index 0e56ace61103..ae621532e716 100644
> --- a/drivers/iio/accel/Kconfig
> +++ b/drivers/iio/accel/Kconfig
> @@ -30,6 +30,35 @@ config ADIS16209
>  	  To compile this driver as a module, say M here: the module will be
>  	  called adis16209.
>  
> +config ADXL313
> +	tristate
> +
> +config ADXL313_I2C
> +	tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer I2C Driver"
> +	depends on I2C
> +	select ADXL313
> +	select REGMAP_I2C
> +	help
> +	  Say Y here if you want to build i2c support for the Analog Devices
> +	  ADXL313 3-axis digital accelerometer.
> +
> +	  To compile this driver as a module, choose M here: the module
> +	  will be called adxl313_i2c and you will also get adxl313_core
> +	  for the core module.
> +
> +config ADXL313_SPI
> +	tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer SPI Driver"
> +	depends on SPI
> +	select ADXL313
> +	select REGMAP_SPI
> +	help
> +	  Say Y here if you want to build spi support for the Analog Devices
> +	  ADXL313 3-axis digital accelerometer.
> +
> +	  To compile this driver as a module, choose M here: the module
> +	  will be called adxl313_spi and you will also get adxl313_core
> +	  for the core module.
> +
>  config ADXL345
>  	tristate
>  
> diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
> index 89280e823bcd..fadc92816e24 100644
> --- a/drivers/iio/accel/Makefile
> +++ b/drivers/iio/accel/Makefile
> @@ -6,6 +6,9 @@
>  # When adding new entries keep the list in alphabetical order
>  obj-$(CONFIG_ADIS16201) += adis16201.o
>  obj-$(CONFIG_ADIS16209) += adis16209.o
> +obj-$(CONFIG_ADXL313) += adxl313_core.o
> +obj-$(CONFIG_ADXL313_I2C) += adxl313_i2c.o
> +obj-$(CONFIG_ADXL313_SPI) += adxl313_spi.o
>  obj-$(CONFIG_ADXL345) += adxl345_core.o
>  obj-$(CONFIG_ADXL345_I2C) += adxl345_i2c.o
>  obj-$(CONFIG_ADXL345_SPI) += adxl345_spi.o
> diff --git a/drivers/iio/accel/adxl313.h b/drivers/iio/accel/adxl313.h
> new file mode 100644
> index 000000000000..72f268e02a80
> --- /dev/null
> +++ b/drivers/iio/accel/adxl313.h
> @@ -0,0 +1,60 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * ADXL313 3-Axis Digital Accelerometer
> + *
> + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> + */
> +
> +#ifndef _ADXL313_H_
> +#define _ADXL313_H_
> +
> +/* ADXL313 register definitions */

If these are only used in the c file, push them down there. Better to
keep what is in the header to absolute minimum.
however I suggest below moving some of this so that won't be true any more,
so maybe you do want to keep them here!


> +#define ADXL313_REG_DEVID0		0x00
> +#define ADXL313_REG_DEVID1		0x01
> +#define ADXL313_REG_PARTID		0x02
> +#define ADXL313_REG_XID			0x04
> +#define ADXL313_REG_SOFT_RESET		0x18
> +#define ADXL313_REG_OFS_AXIS(index)	(0x1E + (index))
> +#define ADXL313_REG_THRESH_ACT		0x24
> +#define ADXL313_REG_ACT_INACT_CTL	0x27
> +#define ADXL313_REG_BW_RATE		0x2C
> +#define ADXL313_REG_POWER_CTL		0x2D
> +#define ADXL313_REG_INT_MAP		0x2F
> +#define ADXL313_REG_DATA_FORMAT		0x31
> +#define ADXL313_REG_DATAX		0x32
> +#define ADXL313_REG_DATAY		0x34
> +#define ADXL313_REG_DATAZ		0x36
> +#define ADXL313_REG_FIFO_CTL		0x38
> +#define ADXL313_REG_FIFO_STATUS		0x39
> +
> +#define ADXL313_DEVID0			0xAD
> +#define ADXL313_DEVID1			0x1D
> +#define ADXL313_PARTID			0xCB
> +#define ADXL313_SOFT_RESET		0x52
> +
> +#define ADXL313_RATE_MSK		GENMASK(3, 0)
> +#define ADXL313_RATE_BASE		6
> +
> +#define ADXL313_POWER_CTL_MSK		GENMASK(3, 2)
> +#define ADXL313_MEASUREMENT_MODE	BIT(3)
> +
> +#define ADXL313_RANGE_MSK		GENMASK(1, 0)
> +#define ADXL313_RANGE_4G		3
> +
> +#define ADXL313_FULL_RES		BIT(3)
> +#define ADXL313_SPI_3WIRE		BIT(6)
> +#define ADXL313_I2C_DISABLE		BIT(6)
> +
> +/*
> + * Scale for any g range is given in datasheet as
> + * 1024 LSB/g = 0.0009765625 * 9.80665 = 0.009576806640625 m/s^2
> + */
> +#define ADXL313_NSCALE 9576806
> +
> +extern const struct regmap_access_table adxl313_readable_regs_table;
> +
> +extern const struct regmap_access_table adxl313_writable_regs_table;
> +
> +int adxl313_core_probe(struct device *dev, struct regmap *regmap,
> +		       const char *name);
> +#endif /* _ADXL313_H_ */
> diff --git a/drivers/iio/accel/adxl313_core.c b/drivers/iio/accel/adxl313_core.c
> new file mode 100644
> index 000000000000..76382ab4f0f4
> --- /dev/null
> +++ b/drivers/iio/accel/adxl313_core.c
> @@ -0,0 +1,323 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * ADXL313 3-Axis Digital Accelerometer
> + *
> + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> + *
> + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/iio/iio.h>
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +
> +#include "adxl313.h"
> +
> +const struct regmap_range adxl313_readable_reg_range[] = {
> +	regmap_reg_range(ADXL313_REG_DEVID0, ADXL313_REG_XID),
> +	regmap_reg_range(ADXL313_REG_SOFT_RESET, ADXL313_REG_SOFT_RESET),
> +	regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
> +	regmap_reg_range(ADXL313_REG_THRESH_ACT, ADXL313_REG_ACT_INACT_CTL),
> +	regmap_reg_range(ADXL313_REG_BW_RATE, ADXL313_REG_FIFO_STATUS)
> +};
> +
> +const struct regmap_access_table adxl313_readable_regs_table = {
> +	.yes_ranges = adxl313_readable_reg_range,
> +	.n_yes_ranges = ARRAY_SIZE(adxl313_readable_reg_range)
> +};
> +EXPORT_SYMBOL_GPL(adxl313_readable_regs_table);
> +
> +const struct regmap_range adxl313_writable_reg_range[] = {
> +	regmap_reg_range(ADXL313_REG_SOFT_RESET, ADXL313_REG_SOFT_RESET),
> +	regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
> +	regmap_reg_range(ADXL313_REG_THRESH_ACT, ADXL313_REG_ACT_INACT_CTL),
> +	regmap_reg_range(ADXL313_REG_BW_RATE, ADXL313_REG_INT_MAP),
> +	regmap_reg_range(ADXL313_REG_DATA_FORMAT, ADXL313_REG_DATA_FORMAT),
> +	regmap_reg_range(ADXL313_REG_FIFO_CTL, ADXL313_REG_FIFO_CTL)
> +};
> +
> +const struct regmap_access_table adxl313_writable_regs_table = {
> +	.yes_ranges = adxl313_writable_reg_range,
> +	.n_yes_ranges = ARRAY_SIZE(adxl313_writable_reg_range)
> +};
> +EXPORT_SYMBOL_GPL(adxl313_writable_regs_table);
> +
> +struct adxl313_data {
> +	struct regmap	*regmap;
> +	struct mutex	lock; /* lock to protect transf_buf */
> +	__le16		transf_buf ____cacheline_aligned;
> +};
> +
> +static const int adxl313_odr_freqs[][2] = {
> +	[0] = { 6, 250000 },
> +	[1] = { 12, 500000 },
> +	[2] = { 25, 0 },
> +	[3] = { 50, 0 },
> +	[4] = { 100, 0 },
> +	[5] = { 200, 0 },
> +	[6] = { 400, 0 },
> +	[7] = { 800, 0 },
> +	[8] = { 1600, 0 },
> +	[9] = { 3200, 0 },
> +};
> +
> +#define ADXL313_ACCEL_CHANNEL(index, addr, axis) {			\
> +	.type = IIO_ACCEL,						\
> +	.address = addr,						\
> +	.modified = 1,							\
> +	.channel2 = IIO_MOD_##axis,					\
> +	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\
> +			      BIT(IIO_CHAN_INFO_CALIBBIAS),		\
> +	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |		\
> +				    BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
> +	.info_mask_shared_by_type_available =				\
> +		BIT(IIO_CHAN_INFO_SAMP_FREQ),				\
> +	.scan_index = index,						\
> +	.scan_type = {							\
> +		.sign = 's',						\
> +		.realbits = 13,						\
> +		.storagebits = 16,					\
> +		.endianness = IIO_LE,					\
> +	},								\
> +}
> +
> +static const struct iio_chan_spec adxl313_channels[] = {
> +	ADXL313_ACCEL_CHANNEL(0, ADXL313_REG_DATAX, X),
> +	ADXL313_ACCEL_CHANNEL(1, ADXL313_REG_DATAY, Y),
> +	ADXL313_ACCEL_CHANNEL(2, ADXL313_REG_DATAZ, Z),
> +};
> +
> +static int adxl313_set_odr(struct adxl313_data *data,
> +			   unsigned int freq1, unsigned int freq2)
> +{
> +	unsigned int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(adxl313_odr_freqs); i++) {
> +		if (adxl313_odr_freqs[i][0] == freq1 &&
> +		    adxl313_odr_freqs[i][1] == freq2)
> +			break;
> +	}
> +
> +	if (i == ARRAY_SIZE(adxl313_odr_freqs))
> +		return -EINVAL;
> +
> +	return regmap_update_bits(data->regmap, ADXL313_REG_BW_RATE,
> +				  ADXL313_RATE_MSK,
> +				  FIELD_PREP(ADXL313_RATE_MSK,
> +					     ADXL313_RATE_BASE + i));
> +}
> +
> +static int adxl313_read_axis(struct adxl313_data *data,
> +			     struct iio_chan_spec const *chan)
> +{
> +	int ret;
> +
> +	mutex_lock(&data->lock);
> +
> +	ret = regmap_bulk_read(data->regmap,
> +			       chan->address,
> +			       &data->transf_buf, 2);
> +	if (ret)
> +		goto unlock_ret;
> +
> +	ret = le16_to_cpu(data->transf_buf);
> +
> +unlock_ret:
> +	mutex_unlock(&data->lock);
> +	return ret;
> +}
> +
> +static int adxl313_read_freq_avail(struct iio_dev *indio_dev,
> +				   struct iio_chan_spec const *chan,
> +				   const int **vals, int *type, int *length,
> +				   long mask)
> +{
> +	switch (mask) {
> +	case IIO_CHAN_INFO_SAMP_FREQ:
> +		*vals = (const int *)adxl313_odr_freqs;
> +		*length = ARRAY_SIZE(adxl313_odr_freqs) * 2;
> +		*type = IIO_VAL_INT_PLUS_MICRO;
> +		return IIO_AVAIL_LIST;
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int adxl313_read_raw(struct iio_dev *indio_dev,
> +			    struct iio_chan_spec const *chan,
> +			    int *val, int *val2, long mask)
> +{
> +	struct adxl313_data *data = iio_priv(indio_dev);
> +	unsigned int regval;
> +	int ret;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		ret = adxl313_read_axis(data, chan);
> +		if (ret < 0)
> +			return ret;
> +
> +		*val = sign_extend32(ret, chan->scan_type.realbits - 1);
> +		return IIO_VAL_INT;
> +	case IIO_CHAN_INFO_SCALE:
> +		*val = 0;
> +		*val2 = ADXL313_NSCALE;
> +		return IIO_VAL_INT_PLUS_NANO;
> +	case IIO_CHAN_INFO_CALIBBIAS:
> +		ret = regmap_read(data->regmap,
> +				  ADXL313_REG_OFS_AXIS(chan->scan_index),
> +				  &regval);
> +		if (ret)
> +			return ret;
> +
> +		/*
> +		 * 8-bit resolution at +/- 0.5g, that is 4x accel data scale
> +		 * factor at full resolution
> +		 */
> +		*val = sign_extend32(regval, 7) * 4;
> +		return IIO_VAL_INT;
> +	case IIO_CHAN_INFO_SAMP_FREQ:
> +		ret = regmap_read(data->regmap, ADXL313_REG_BW_RATE, &regval);
> +		if (ret)
> +			return ret;
> +
> +		ret = FIELD_GET(ADXL313_RATE_MSK, regval) - ADXL313_RATE_BASE;
> +		*val = adxl313_odr_freqs[ret][0];
> +		*val2 = adxl313_odr_freqs[ret][1];
> +		return IIO_VAL_INT_PLUS_MICRO;
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int adxl313_write_raw(struct iio_dev *indio_dev,
> +			     struct iio_chan_spec const *chan,
> +			     int val, int val2, long mask)
> +{
> +	struct adxl313_data *data = iio_priv(indio_dev);
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_CALIBBIAS:
> +		/*
> +		 * 8-bit resolution at +/- 0.5g, that is 4x accel data scale
> +		 * factor at full resolution
> +		 */
> +		if (val > 127 * 4 || val < -128 * 4)
> +			return -EINVAL;
> +
> +		return regmap_write(data->regmap,
> +				    ADXL313_REG_OFS_AXIS(chan->scan_index),
> +				    val / 4);
> +	case IIO_CHAN_INFO_SAMP_FREQ:
> +		return adxl313_set_odr(data, val, val2);
> +	}
> +
> +	return -EINVAL;

Put this as a default in the case otherwise you might get warnings saying you
don't handle all the possible values.

> +}
> +
> +static const struct iio_info adxl313_info = {
> +	.read_raw	= adxl313_read_raw,
> +	.write_raw	= adxl313_write_raw,
> +	.read_avail	= adxl313_read_freq_avail
> +};
> +
> +static int adxl313_setup(struct device *dev, struct adxl313_data *data)
> +{
> +	unsigned int regval;
> +	int ret;
> +
> +	/* Ensures the device is in a consistent state after start up */
> +	ret = regmap_write(data->regmap, ADXL313_REG_SOFT_RESET,
> +			   ADXL313_SOFT_RESET);
> +	if (ret)
> +		return ret;
> +
> +	if (device_property_read_bool(dev, "spi-3wire")) {

Rather odd to see spi specific stuff in here.  Perhaps provide a callback to
common probe if it needs to be done at this point in bringing the device up.
However, I think you can just do this before calling the common_probe()

> +		ret = regmap_write(data->regmap, ADXL313_REG_DATA_FORMAT,
> +				   ADXL313_SPI_3WIRE);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	ret = regmap_read(data->regmap, ADXL313_REG_DEVID0, &regval);
> +	if (ret)
> +		return ret;
> +
> +	if (regval != ADXL313_DEVID0) {
> +		dev_err(dev, "Invalid manufacturer ID: 0x%02x\n", regval);
> +		return -ENODEV;
> +	}
> +
> +	ret = regmap_read(data->regmap, ADXL313_REG_DEVID1, &regval);
> +	if (ret)
> +		return ret;
> +
> +	if (regval != ADXL313_DEVID1) {
> +		dev_err(dev, "Invalid mems ID: 0x%02x\n", regval);
> +		return -ENODEV;
> +	}
> +
> +	ret = regmap_read(data->regmap, ADXL313_REG_PARTID, &regval);
> +	if (ret)
> +		return ret;
> +
> +	if (regval != ADXL313_PARTID) {
> +		dev_err(dev, "Invalid device ID: 0x%02x\n", regval);
> +		return -ENODEV;
> +	}
> +
> +	/* Sets the range to +/- 4g */
> +	ret = regmap_update_bits(data->regmap, ADXL313_REG_DATA_FORMAT,
> +				 ADXL313_RANGE_MSK,
> +				 FIELD_PREP(ADXL313_RANGE_MSK,
> +					    ADXL313_RANGE_4G));
> +	if (ret)
> +		return ret;
> +
> +	/* Enables full resolution */
> +	ret = regmap_update_bits(data->regmap, ADXL313_REG_DATA_FORMAT,
> +				 ADXL313_FULL_RES, ADXL313_FULL_RES);
> +	if (ret)
> +		return ret;
> +
> +	/* Enables measurement mode */
> +	return regmap_update_bits(data->regmap, ADXL313_REG_POWER_CTL,
> +				  ADXL313_POWER_CTL_MSK,
> +				  ADXL313_MEASUREMENT_MODE);
> +}
> +
> +int adxl313_core_probe(struct device *dev, struct regmap *regmap,
> +		       const char *name)
> +{
> +	struct adxl313_data *data;
> +	struct iio_dev *indio_dev;
> +	int ret;
> +
> +	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
> +	if (!indio_dev)
> +		return -ENOMEM;
> +
> +	data = iio_priv(indio_dev);
> +	data->regmap = regmap;
> +	mutex_init(&data->lock);
> +
> +	indio_dev->name = name;
> +	indio_dev->info = &adxl313_info;
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +	indio_dev->channels = adxl313_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(adxl313_channels);
> +
> +	ret = adxl313_setup(dev, data);
> +	if (ret) {
> +		dev_err(dev, "ADXL313 setup failed\n");
> +		return ret;
> +	}
> +
> +	return devm_iio_device_register(dev, indio_dev);
> +}
> +EXPORT_SYMBOL_GPL(adxl313_core_probe);
> +
> +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer core driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/iio/accel/adxl313_i2c.c b/drivers/iio/accel/adxl313_i2c.c
> new file mode 100644
> index 000000000000..65050a2fbd38
> --- /dev/null
> +++ b/drivers/iio/accel/adxl313_i2c.c
> @@ -0,0 +1,65 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * ADXL313 3-Axis Digital Accelerometer
> + *
> + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> + *
> + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> + */
> +
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +
> +#include "adxl313.h"
> +
> +static const struct regmap_config adxl313_i2c_regmap_config = {
> +	.reg_bits	= 8,
> +	.val_bits	= 8,
> +	.rd_table	= &adxl313_readable_regs_table,
> +	.wr_table	= &adxl313_writable_regs_table,
> +	.max_register	= 0x39
> +};
> +
> +static int adxl313_i2c_probe(struct i2c_client *client)
> +{
> +	struct regmap *regmap;
> +
> +	regmap = devm_regmap_init_i2c(client, &adxl313_i2c_regmap_config);
> +	if (IS_ERR(regmap)) {
> +		dev_err(&client->dev, "Error initializing i2c regmap: %ld\n",
> +			PTR_ERR(regmap));
> +		return PTR_ERR(regmap);
> +	}
> +
> +	return adxl313_core_probe(&client->dev, regmap, client->name);
> +}
> +
> +static const struct i2c_device_id adxl313_i2c_id[] = {
> +	{ "adxl313", 0 },

No real need to set the data value if it's just going to be 0.
	{ "adl313 },
is fine.

> +	{ }
> +};
> +
> +MODULE_DEVICE_TABLE(i2c, adxl313_i2c_id);
> +
> +static const struct of_device_id adxl313_of_match[] = {
> +	{ .compatible = "adi,adxl313" },
> +	{ },
> +};
> +
> +MODULE_DEVICE_TABLE(of, adxl313_of_match);
> +
> +static struct i2c_driver adxl313_i2c_driver = {
> +	.driver = {
> +		.name	= "adxl313_i2c",
> +		.of_match_table = adxl313_of_match,
> +	},
> +	.probe_new	= adxl313_i2c_probe,
> +	.id_table	= adxl313_i2c_id,
> +};
> +
> +module_i2c_driver(adxl313_i2c_driver);
> +
> +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer I2C driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/iio/accel/adxl313_spi.c b/drivers/iio/accel/adxl313_spi.c
> new file mode 100644
> index 000000000000..7c58c9ff8985
> --- /dev/null
> +++ b/drivers/iio/accel/adxl313_spi.c
> @@ -0,0 +1,74 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * ADXL313 3-Axis Digital Accelerometer
> + *
> + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> + *
> + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> + */
> +
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +#include <linux/spi/spi.h>
> +
> +#include "adxl313.h"
> +
> +static const struct regmap_config adxl313_spi_regmap_config = {
> +	.reg_bits	= 8,
> +	.val_bits	= 8,
> +	.rd_table	= &adxl313_readable_regs_table,
> +	.wr_table	= &adxl313_writable_regs_table,
> +	.max_register	= 0x39,
> +	 /* Setting bits 7 and 6 enables multiple-byte read */
> +	.read_flag_mask	= BIT(7) | BIT(6)
> +};
> +
> +static int adxl313_spi_probe(struct spi_device *spi)
> +{
> +	const struct spi_device_id *id = spi_get_device_id(spi);
> +	struct regmap *regmap;
> +	int ret;
> +
> +	regmap = devm_regmap_init_spi(spi, &adxl313_spi_regmap_config);
> +	if (IS_ERR(regmap)) {
> +		dev_err(&spi->dev, "Error initializing spi regmap: %ld\n",
> +			PTR_ERR(regmap));
> +		return PTR_ERR(regmap);
> +	}
> +
> +	ret = adxl313_core_probe(&spi->dev, regmap, id->name);
> +	if (ret < 0)
> +		return ret;
> +
> +	return regmap_update_bits(regmap, ADXL313_REG_POWER_CTL,
> +				  ADXL313_I2C_DISABLE, ADXL313_I2C_DISABLE);

Why is this only done after the rest of probe?  Needs a comment perhaps.
Normally I'd expect the core probe and hence exposure of the device
to userspace etc to be the last thing done.

> +}
> +
> +static const struct spi_device_id adxl313_spi_id[] = {
> +	{ "adxl313", 0 },
> +	{ }
> +};
> +
> +MODULE_DEVICE_TABLE(spi, adxl313_spi_id);
> +
> +static const struct of_device_id adxl313_of_match[] = {
> +	{ .compatible = "adi,adxl313" },
> +	{ },
> +};
> +
> +MODULE_DEVICE_TABLE(of, adxl313_of_match);
> +
> +static struct spi_driver adxl313_spi_driver = {
> +	.driver = {
> +		.name	= "adxl313_spi",
> +		.of_match_table = adxl313_of_match,
> +	},
> +	.probe		= adxl313_spi_probe,
> +	.id_table	= adxl313_spi_id,
> +};
> +
> +module_spi_driver(adxl313_spi_driver);
> +
> +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer SPI driver");
> +MODULE_LICENSE("GPL v2");


^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH 2/2] iio: accel: Add driver support for ADXL313
  2021-08-01 18:12   ` Jonathan Cameron
@ 2021-08-02  6:57     ` Alexandru Ardelean
  2021-08-02 17:28       ` Lucas Stankus
  2021-08-02 17:15     ` Lucas Stankus
  1 sibling, 1 reply; 14+ messages in thread
From: Alexandru Ardelean @ 2021-08-02  6:57 UTC (permalink / raw)
  To: Jonathan Cameron
  Cc: Lucas Stankus, Lars-Peter Clausen, Hennerich, Michael,
	Rob Herring, Bogdan, Dragos, Berghe, Darius, linux-iio,
	devicetree, LKML

On Sun, Aug 1, 2021 at 9:09 PM Jonathan Cameron <jic23@kernel.org> wrote:
>
> On Sat, 31 Jul 2021 17:36:48 -0300
> Lucas Stankus <lucas.p.stankus@gmail.com> wrote:
>
> > ADXL313 is a small, thin, low power, 3-axis accelerometer with high
> > resolution measurement up to +/-4g. It includes an integrated 32-level
> > FIFO and has activity and inactivity sensing capabilities.
> >
> > Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> >
> > Signed-off-by: Lucas Stankus <lucas.p.stankus@gmail.com>
>
> Very nice.  A few really minor things inline.
>
> Jonathan
>
> > ---
> >  MAINTAINERS                      |   9 +
> >  drivers/iio/accel/Kconfig        |  29 +++
> >  drivers/iio/accel/Makefile       |   3 +
> >  drivers/iio/accel/adxl313.h      |  60 ++++++
> >  drivers/iio/accel/adxl313_core.c | 323 +++++++++++++++++++++++++++++++
> >  drivers/iio/accel/adxl313_i2c.c  |  65 +++++++
> >  drivers/iio/accel/adxl313_spi.c  |  74 +++++++
> >  7 files changed, 563 insertions(+)
> >  create mode 100644 drivers/iio/accel/adxl313.h
> >  create mode 100644 drivers/iio/accel/adxl313_core.c
> >  create mode 100644 drivers/iio/accel/adxl313_i2c.c
> >  create mode 100644 drivers/iio/accel/adxl313_spi.c
> >
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index a61f4f3b78a9..1fc88723e632 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -585,6 +585,15 @@ L:       platform-driver-x86@vger.kernel.org
> >  S:   Maintained
> >  F:   drivers/platform/x86/adv_swbutton.c
> >
> > +ADXL313 THREE-AXIS DIGITAL ACCELEROMETER DRIVER
> > +M:   Lucas Stankus <lucas.p.stankus@gmail.com>
> > +S:   Supported
> > +F:   Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
> > +F:   drivers/iio/accel/adxl313.h
> > +F:   drivers/iio/accel/adxl313_core.c
> > +F:   drivers/iio/accel/adxl313_i2c.c
> > +F:   drivers/iio/accel/adxl313_spi.c
> > +
> >  ADXL34X THREE-AXIS DIGITAL ACCELEROMETER DRIVER (ADXL345/ADXL346)
> >  M:   Michael Hennerich <michael.hennerich@analog.com>
> >  S:   Supported
> > diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
> > index 0e56ace61103..ae621532e716 100644
> > --- a/drivers/iio/accel/Kconfig
> > +++ b/drivers/iio/accel/Kconfig
> > @@ -30,6 +30,35 @@ config ADIS16209
> >         To compile this driver as a module, say M here: the module will be
> >         called adis16209.
> >
> > +config ADXL313
> > +     tristate
> > +
> > +config ADXL313_I2C
> > +     tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer I2C Driver"
> > +     depends on I2C
> > +     select ADXL313
> > +     select REGMAP_I2C
> > +     help
> > +       Say Y here if you want to build i2c support for the Analog Devices
> > +       ADXL313 3-axis digital accelerometer.
> > +
> > +       To compile this driver as a module, choose M here: the module
> > +       will be called adxl313_i2c and you will also get adxl313_core
> > +       for the core module.
> > +
> > +config ADXL313_SPI
> > +     tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer SPI Driver"
> > +     depends on SPI
> > +     select ADXL313
> > +     select REGMAP_SPI
> > +     help
> > +       Say Y here if you want to build spi support for the Analog Devices
> > +       ADXL313 3-axis digital accelerometer.
> > +
> > +       To compile this driver as a module, choose M here: the module
> > +       will be called adxl313_spi and you will also get adxl313_core
> > +       for the core module.
> > +
> >  config ADXL345
> >       tristate
> >
> > diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
> > index 89280e823bcd..fadc92816e24 100644
> > --- a/drivers/iio/accel/Makefile
> > +++ b/drivers/iio/accel/Makefile
> > @@ -6,6 +6,9 @@
> >  # When adding new entries keep the list in alphabetical order
> >  obj-$(CONFIG_ADIS16201) += adis16201.o
> >  obj-$(CONFIG_ADIS16209) += adis16209.o
> > +obj-$(CONFIG_ADXL313) += adxl313_core.o
> > +obj-$(CONFIG_ADXL313_I2C) += adxl313_i2c.o
> > +obj-$(CONFIG_ADXL313_SPI) += adxl313_spi.o
> >  obj-$(CONFIG_ADXL345) += adxl345_core.o
> >  obj-$(CONFIG_ADXL345_I2C) += adxl345_i2c.o
> >  obj-$(CONFIG_ADXL345_SPI) += adxl345_spi.o
> > diff --git a/drivers/iio/accel/adxl313.h b/drivers/iio/accel/adxl313.h
> > new file mode 100644
> > index 000000000000..72f268e02a80
> > --- /dev/null
> > +++ b/drivers/iio/accel/adxl313.h
> > @@ -0,0 +1,60 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +/*
> > + * ADXL313 3-Axis Digital Accelerometer
> > + *
> > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > + */
> > +
> > +#ifndef _ADXL313_H_
> > +#define _ADXL313_H_
> > +
> > +/* ADXL313 register definitions */
>
> If these are only used in the c file, push them down there. Better to
> keep what is in the header to absolute minimum.
> however I suggest below moving some of this so that won't be true any more,
> so maybe you do want to keep them here!
>
>
> > +#define ADXL313_REG_DEVID0           0x00
> > +#define ADXL313_REG_DEVID1           0x01
> > +#define ADXL313_REG_PARTID           0x02
> > +#define ADXL313_REG_XID                      0x04
> > +#define ADXL313_REG_SOFT_RESET               0x18
> > +#define ADXL313_REG_OFS_AXIS(index)  (0x1E + (index))
> > +#define ADXL313_REG_THRESH_ACT               0x24
> > +#define ADXL313_REG_ACT_INACT_CTL    0x27
> > +#define ADXL313_REG_BW_RATE          0x2C
> > +#define ADXL313_REG_POWER_CTL                0x2D
> > +#define ADXL313_REG_INT_MAP          0x2F
> > +#define ADXL313_REG_DATA_FORMAT              0x31
> > +#define ADXL313_REG_DATAX            0x32
> > +#define ADXL313_REG_DATAY            0x34
> > +#define ADXL313_REG_DATAZ            0x36
> > +#define ADXL313_REG_FIFO_CTL         0x38
> > +#define ADXL313_REG_FIFO_STATUS              0x39
> > +
> > +#define ADXL313_DEVID0                       0xAD
> > +#define ADXL313_DEVID1                       0x1D
> > +#define ADXL313_PARTID                       0xCB
> > +#define ADXL313_SOFT_RESET           0x52
> > +
> > +#define ADXL313_RATE_MSK             GENMASK(3, 0)
> > +#define ADXL313_RATE_BASE            6
> > +
> > +#define ADXL313_POWER_CTL_MSK                GENMASK(3, 2)
> > +#define ADXL313_MEASUREMENT_MODE     BIT(3)
> > +
> > +#define ADXL313_RANGE_MSK            GENMASK(1, 0)
> > +#define ADXL313_RANGE_4G             3
> > +
> > +#define ADXL313_FULL_RES             BIT(3)
> > +#define ADXL313_SPI_3WIRE            BIT(6)
> > +#define ADXL313_I2C_DISABLE          BIT(6)
> > +
> > +/*
> > + * Scale for any g range is given in datasheet as
> > + * 1024 LSB/g = 0.0009765625 * 9.80665 = 0.009576806640625 m/s^2
> > + */
> > +#define ADXL313_NSCALE 9576806
> > +
> > +extern const struct regmap_access_table adxl313_readable_regs_table;
> > +
> > +extern const struct regmap_access_table adxl313_writable_regs_table;
> > +
> > +int adxl313_core_probe(struct device *dev, struct regmap *regmap,
> > +                    const char *name);
> > +#endif /* _ADXL313_H_ */
> > diff --git a/drivers/iio/accel/adxl313_core.c b/drivers/iio/accel/adxl313_core.c
> > new file mode 100644
> > index 000000000000..76382ab4f0f4
> > --- /dev/null
> > +++ b/drivers/iio/accel/adxl313_core.c
> > @@ -0,0 +1,323 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * ADXL313 3-Axis Digital Accelerometer
> > + *
> > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > + *
> > + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > + */
> > +
> > +#include <linux/bitfield.h>
> > +#include <linux/iio/iio.h>
> > +#include <linux/module.h>
> > +#include <linux/regmap.h>
> > +
> > +#include "adxl313.h"
> > +
> > +const struct regmap_range adxl313_readable_reg_range[] = {
> > +     regmap_reg_range(ADXL313_REG_DEVID0, ADXL313_REG_XID),
> > +     regmap_reg_range(ADXL313_REG_SOFT_RESET, ADXL313_REG_SOFT_RESET),
> > +     regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
> > +     regmap_reg_range(ADXL313_REG_THRESH_ACT, ADXL313_REG_ACT_INACT_CTL),
> > +     regmap_reg_range(ADXL313_REG_BW_RATE, ADXL313_REG_FIFO_STATUS)
> > +};
> > +
> > +const struct regmap_access_table adxl313_readable_regs_table = {
> > +     .yes_ranges = adxl313_readable_reg_range,
> > +     .n_yes_ranges = ARRAY_SIZE(adxl313_readable_reg_range)
> > +};
> > +EXPORT_SYMBOL_GPL(adxl313_readable_regs_table);
> > +
> > +const struct regmap_range adxl313_writable_reg_range[] = {
> > +     regmap_reg_range(ADXL313_REG_SOFT_RESET, ADXL313_REG_SOFT_RESET),
> > +     regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
> > +     regmap_reg_range(ADXL313_REG_THRESH_ACT, ADXL313_REG_ACT_INACT_CTL),
> > +     regmap_reg_range(ADXL313_REG_BW_RATE, ADXL313_REG_INT_MAP),
> > +     regmap_reg_range(ADXL313_REG_DATA_FORMAT, ADXL313_REG_DATA_FORMAT),
> > +     regmap_reg_range(ADXL313_REG_FIFO_CTL, ADXL313_REG_FIFO_CTL)
> > +};
> > +
> > +const struct regmap_access_table adxl313_writable_regs_table = {
> > +     .yes_ranges = adxl313_writable_reg_range,
> > +     .n_yes_ranges = ARRAY_SIZE(adxl313_writable_reg_range)
> > +};
> > +EXPORT_SYMBOL_GPL(adxl313_writable_regs_table);
> > +
> > +struct adxl313_data {
> > +     struct regmap   *regmap;
> > +     struct mutex    lock; /* lock to protect transf_buf */
> > +     __le16          transf_buf ____cacheline_aligned;
> > +};
> > +
> > +static const int adxl313_odr_freqs[][2] = {
> > +     [0] = { 6, 250000 },
> > +     [1] = { 12, 500000 },
> > +     [2] = { 25, 0 },
> > +     [3] = { 50, 0 },
> > +     [4] = { 100, 0 },
> > +     [5] = { 200, 0 },
> > +     [6] = { 400, 0 },
> > +     [7] = { 800, 0 },
> > +     [8] = { 1600, 0 },
> > +     [9] = { 3200, 0 },
> > +};
> > +
> > +#define ADXL313_ACCEL_CHANNEL(index, addr, axis) {                   \
> > +     .type = IIO_ACCEL,                                              \
> > +     .address = addr,                                                \
> > +     .modified = 1,                                                  \
> > +     .channel2 = IIO_MOD_##axis,                                     \
> > +     .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |                  \
> > +                           BIT(IIO_CHAN_INFO_CALIBBIAS),             \
> > +     .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |          \
> > +                                 BIT(IIO_CHAN_INFO_SAMP_FREQ),       \
> > +     .info_mask_shared_by_type_available =                           \
> > +             BIT(IIO_CHAN_INFO_SAMP_FREQ),                           \
> > +     .scan_index = index,                                            \
> > +     .scan_type = {                                                  \
> > +             .sign = 's',                                            \
> > +             .realbits = 13,                                         \
> > +             .storagebits = 16,                                      \
> > +             .endianness = IIO_LE,                                   \
> > +     },                                                              \
> > +}
> > +
> > +static const struct iio_chan_spec adxl313_channels[] = {
> > +     ADXL313_ACCEL_CHANNEL(0, ADXL313_REG_DATAX, X),
> > +     ADXL313_ACCEL_CHANNEL(1, ADXL313_REG_DATAY, Y),
> > +     ADXL313_ACCEL_CHANNEL(2, ADXL313_REG_DATAZ, Z),
> > +};
> > +
> > +static int adxl313_set_odr(struct adxl313_data *data,
> > +                        unsigned int freq1, unsigned int freq2)
> > +{
> > +     unsigned int i;
> > +
> > +     for (i = 0; i < ARRAY_SIZE(adxl313_odr_freqs); i++) {
> > +             if (adxl313_odr_freqs[i][0] == freq1 &&
> > +                 adxl313_odr_freqs[i][1] == freq2)
> > +                     break;
> > +     }
> > +
> > +     if (i == ARRAY_SIZE(adxl313_odr_freqs))
> > +             return -EINVAL;
> > +
> > +     return regmap_update_bits(data->regmap, ADXL313_REG_BW_RATE,
> > +                               ADXL313_RATE_MSK,
> > +                               FIELD_PREP(ADXL313_RATE_MSK,
> > +                                          ADXL313_RATE_BASE + i));
> > +}
> > +
> > +static int adxl313_read_axis(struct adxl313_data *data,
> > +                          struct iio_chan_spec const *chan)
> > +{
> > +     int ret;
> > +
> > +     mutex_lock(&data->lock);
> > +
> > +     ret = regmap_bulk_read(data->regmap,
> > +                            chan->address,
> > +                            &data->transf_buf, 2);
> > +     if (ret)
> > +             goto unlock_ret;
> > +
> > +     ret = le16_to_cpu(data->transf_buf);
> > +
> > +unlock_ret:
> > +     mutex_unlock(&data->lock);
> > +     return ret;
> > +}
> > +
> > +static int adxl313_read_freq_avail(struct iio_dev *indio_dev,
> > +                                struct iio_chan_spec const *chan,
> > +                                const int **vals, int *type, int *length,
> > +                                long mask)
> > +{
> > +     switch (mask) {
> > +     case IIO_CHAN_INFO_SAMP_FREQ:
> > +             *vals = (const int *)adxl313_odr_freqs;
> > +             *length = ARRAY_SIZE(adxl313_odr_freqs) * 2;
> > +             *type = IIO_VAL_INT_PLUS_MICRO;
> > +             return IIO_AVAIL_LIST;
> > +     }
> > +
> > +     return -EINVAL;
> > +}
> > +
> > +static int adxl313_read_raw(struct iio_dev *indio_dev,
> > +                         struct iio_chan_spec const *chan,
> > +                         int *val, int *val2, long mask)
> > +{
> > +     struct adxl313_data *data = iio_priv(indio_dev);
> > +     unsigned int regval;
> > +     int ret;
> > +
> > +     switch (mask) {
> > +     case IIO_CHAN_INFO_RAW:
> > +             ret = adxl313_read_axis(data, chan);
> > +             if (ret < 0)
> > +                     return ret;
> > +
> > +             *val = sign_extend32(ret, chan->scan_type.realbits - 1);
> > +             return IIO_VAL_INT;
> > +     case IIO_CHAN_INFO_SCALE:
> > +             *val = 0;
> > +             *val2 = ADXL313_NSCALE;
> > +             return IIO_VAL_INT_PLUS_NANO;
> > +     case IIO_CHAN_INFO_CALIBBIAS:
> > +             ret = regmap_read(data->regmap,
> > +                               ADXL313_REG_OFS_AXIS(chan->scan_index),
> > +                               &regval);
> > +             if (ret)
> > +                     return ret;
> > +
> > +             /*
> > +              * 8-bit resolution at +/- 0.5g, that is 4x accel data scale
> > +              * factor at full resolution
> > +              */
> > +             *val = sign_extend32(regval, 7) * 4;
> > +             return IIO_VAL_INT;
> > +     case IIO_CHAN_INFO_SAMP_FREQ:
> > +             ret = regmap_read(data->regmap, ADXL313_REG_BW_RATE, &regval);
> > +             if (ret)
> > +                     return ret;
> > +
> > +             ret = FIELD_GET(ADXL313_RATE_MSK, regval) - ADXL313_RATE_BASE;
> > +             *val = adxl313_odr_freqs[ret][0];
> > +             *val2 = adxl313_odr_freqs[ret][1];
> > +             return IIO_VAL_INT_PLUS_MICRO;
> > +     }
> > +
> > +     return -EINVAL;
> > +}
> > +
> > +static int adxl313_write_raw(struct iio_dev *indio_dev,
> > +                          struct iio_chan_spec const *chan,
> > +                          int val, int val2, long mask)
> > +{
> > +     struct adxl313_data *data = iio_priv(indio_dev);
> > +
> > +     switch (mask) {
> > +     case IIO_CHAN_INFO_CALIBBIAS:
> > +             /*
> > +              * 8-bit resolution at +/- 0.5g, that is 4x accel data scale
> > +              * factor at full resolution
> > +              */
> > +             if (val > 127 * 4 || val < -128 * 4)
> > +                     return -EINVAL;
> > +
> > +             return regmap_write(data->regmap,
> > +                                 ADXL313_REG_OFS_AXIS(chan->scan_index),
> > +                                 val / 4);
> > +     case IIO_CHAN_INFO_SAMP_FREQ:
> > +             return adxl313_set_odr(data, val, val2);
> > +     }
> > +
> > +     return -EINVAL;
>
> Put this as a default in the case otherwise you might get warnings saying you
> don't handle all the possible values.
>
> > +}
> > +
> > +static const struct iio_info adxl313_info = {
> > +     .read_raw       = adxl313_read_raw,
> > +     .write_raw      = adxl313_write_raw,
> > +     .read_avail     = adxl313_read_freq_avail
> > +};
> > +
> > +static int adxl313_setup(struct device *dev, struct adxl313_data *data)
> > +{
> > +     unsigned int regval;
> > +     int ret;
> > +
> > +     /* Ensures the device is in a consistent state after start up */
> > +     ret = regmap_write(data->regmap, ADXL313_REG_SOFT_RESET,
> > +                        ADXL313_SOFT_RESET);
> > +     if (ret)
> > +             return ret;
> > +
> > +     if (device_property_read_bool(dev, "spi-3wire")) {
>
> Rather odd to see spi specific stuff in here.  Perhaps provide a callback to
> common probe if it needs to be done at this point in bringing the device up.
> However, I think you can just do this before calling the common_probe()

This is a recurring theme in some ADI chips, where the chip supports
both 3wire and 4wire SPI modes.

But this has some tendency to create confusion and a bit duplication.
Because "spi-3wire" is also valid in `drivers/spi/spi.c` in the SPI framework.
So, it gets parsed [only for OF] by the SPI framework [hence the duplication].
But, then,if the SPI controller doesn't support 3wire mode, this
setting gets invalidated inside the SPI framework; the chip remains in
3wire mode anyway.

[if the above happens] This setting can work if there is a passive
SPI-mode converter [from 4wire to 3wire]
Which is not a great way to describe the HW, but it's the best we can
do for now.

This comes back to an older discussion about overriding spi-cpol &
spi-cpha in the DT in case there are some weird board designs.
The driver would specify some mode, but the DT could override it, in
case it is needed.
I had a plan to do a general approach for this, but did not get to it.

>
> > +             ret = regmap_write(data->regmap, ADXL313_REG_DATA_FORMAT,
> > +                                ADXL313_SPI_3WIRE);
> > +             if (ret)
> > +                     return ret;
> > +     }
> > +
> > +     ret = regmap_read(data->regmap, ADXL313_REG_DEVID0, &regval);
> > +     if (ret)
> > +             return ret;
> > +
> > +     if (regval != ADXL313_DEVID0) {
> > +             dev_err(dev, "Invalid manufacturer ID: 0x%02x\n", regval);
> > +             return -ENODEV;
> > +     }
> > +
> > +     ret = regmap_read(data->regmap, ADXL313_REG_DEVID1, &regval);
> > +     if (ret)
> > +             return ret;
> > +
> > +     if (regval != ADXL313_DEVID1) {
> > +             dev_err(dev, "Invalid mems ID: 0x%02x\n", regval);
> > +             return -ENODEV;
> > +     }
> > +
> > +     ret = regmap_read(data->regmap, ADXL313_REG_PARTID, &regval);
> > +     if (ret)
> > +             return ret;
> > +
> > +     if (regval != ADXL313_PARTID) {
> > +             dev_err(dev, "Invalid device ID: 0x%02x\n", regval);
> > +             return -ENODEV;
> > +     }
> > +
> > +     /* Sets the range to +/- 4g */
> > +     ret = regmap_update_bits(data->regmap, ADXL313_REG_DATA_FORMAT,
> > +                              ADXL313_RANGE_MSK,
> > +                              FIELD_PREP(ADXL313_RANGE_MSK,
> > +                                         ADXL313_RANGE_4G));
> > +     if (ret)
> > +             return ret;
> > +
> > +     /* Enables full resolution */
> > +     ret = regmap_update_bits(data->regmap, ADXL313_REG_DATA_FORMAT,
> > +                              ADXL313_FULL_RES, ADXL313_FULL_RES);
> > +     if (ret)
> > +             return ret;
> > +
> > +     /* Enables measurement mode */
> > +     return regmap_update_bits(data->regmap, ADXL313_REG_POWER_CTL,
> > +                               ADXL313_POWER_CTL_MSK,
> > +                               ADXL313_MEASUREMENT_MODE);
> > +}
> > +
> > +int adxl313_core_probe(struct device *dev, struct regmap *regmap,
> > +                    const char *name)
> > +{
> > +     struct adxl313_data *data;
> > +     struct iio_dev *indio_dev;
> > +     int ret;
> > +
> > +     indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
> > +     if (!indio_dev)
> > +             return -ENOMEM;
> > +
> > +     data = iio_priv(indio_dev);
> > +     data->regmap = regmap;
> > +     mutex_init(&data->lock);
> > +
> > +     indio_dev->name = name;
> > +     indio_dev->info = &adxl313_info;
> > +     indio_dev->modes = INDIO_DIRECT_MODE;
> > +     indio_dev->channels = adxl313_channels;
> > +     indio_dev->num_channels = ARRAY_SIZE(adxl313_channels);
> > +
> > +     ret = adxl313_setup(dev, data);
> > +     if (ret) {
> > +             dev_err(dev, "ADXL313 setup failed\n");
> > +             return ret;
> > +     }
> > +
> > +     return devm_iio_device_register(dev, indio_dev);
> > +}
> > +EXPORT_SYMBOL_GPL(adxl313_core_probe);
> > +
> > +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> > +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer core driver");
> > +MODULE_LICENSE("GPL v2");
> > diff --git a/drivers/iio/accel/adxl313_i2c.c b/drivers/iio/accel/adxl313_i2c.c
> > new file mode 100644
> > index 000000000000..65050a2fbd38
> > --- /dev/null
> > +++ b/drivers/iio/accel/adxl313_i2c.c
> > @@ -0,0 +1,65 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * ADXL313 3-Axis Digital Accelerometer
> > + *
> > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > + *
> > + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > + */
> > +
> > +#include <linux/i2c.h>
> > +#include <linux/module.h>
> > +#include <linux/regmap.h>
> > +
> > +#include "adxl313.h"
> > +
> > +static const struct regmap_config adxl313_i2c_regmap_config = {
> > +     .reg_bits       = 8,
> > +     .val_bits       = 8,
> > +     .rd_table       = &adxl313_readable_regs_table,
> > +     .wr_table       = &adxl313_writable_regs_table,
> > +     .max_register   = 0x39
> > +};
> > +
> > +static int adxl313_i2c_probe(struct i2c_client *client)
> > +{
> > +     struct regmap *regmap;
> > +
> > +     regmap = devm_regmap_init_i2c(client, &adxl313_i2c_regmap_config);
> > +     if (IS_ERR(regmap)) {
> > +             dev_err(&client->dev, "Error initializing i2c regmap: %ld\n",
> > +                     PTR_ERR(regmap));
> > +             return PTR_ERR(regmap);
> > +     }
> > +
> > +     return adxl313_core_probe(&client->dev, regmap, client->name);
> > +}
> > +
> > +static const struct i2c_device_id adxl313_i2c_id[] = {
> > +     { "adxl313", 0 },
>
> No real need to set the data value if it's just going to be 0.
>         { "adl313 },
> is fine.
>
> > +     { }
> > +};
> > +
> > +MODULE_DEVICE_TABLE(i2c, adxl313_i2c_id);
> > +
> > +static const struct of_device_id adxl313_of_match[] = {
> > +     { .compatible = "adi,adxl313" },
> > +     { },
> > +};
> > +
> > +MODULE_DEVICE_TABLE(of, adxl313_of_match);
> > +
> > +static struct i2c_driver adxl313_i2c_driver = {
> > +     .driver = {
> > +             .name   = "adxl313_i2c",
> > +             .of_match_table = adxl313_of_match,
> > +     },
> > +     .probe_new      = adxl313_i2c_probe,
> > +     .id_table       = adxl313_i2c_id,
> > +};
> > +
> > +module_i2c_driver(adxl313_i2c_driver);
> > +
> > +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> > +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer I2C driver");
> > +MODULE_LICENSE("GPL v2");
> > diff --git a/drivers/iio/accel/adxl313_spi.c b/drivers/iio/accel/adxl313_spi.c
> > new file mode 100644
> > index 000000000000..7c58c9ff8985
> > --- /dev/null
> > +++ b/drivers/iio/accel/adxl313_spi.c
> > @@ -0,0 +1,74 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * ADXL313 3-Axis Digital Accelerometer
> > + *
> > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > + *
> > + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > + */
> > +
> > +#include <linux/module.h>
> > +#include <linux/regmap.h>
> > +#include <linux/spi/spi.h>
> > +
> > +#include "adxl313.h"
> > +
> > +static const struct regmap_config adxl313_spi_regmap_config = {
> > +     .reg_bits       = 8,
> > +     .val_bits       = 8,
> > +     .rd_table       = &adxl313_readable_regs_table,
> > +     .wr_table       = &adxl313_writable_regs_table,
> > +     .max_register   = 0x39,
> > +      /* Setting bits 7 and 6 enables multiple-byte read */
> > +     .read_flag_mask = BIT(7) | BIT(6)
> > +};
> > +
> > +static int adxl313_spi_probe(struct spi_device *spi)
> > +{
> > +     const struct spi_device_id *id = spi_get_device_id(spi);
> > +     struct regmap *regmap;
> > +     int ret;
> > +
> > +     regmap = devm_regmap_init_spi(spi, &adxl313_spi_regmap_config);
> > +     if (IS_ERR(regmap)) {
> > +             dev_err(&spi->dev, "Error initializing spi regmap: %ld\n",
> > +                     PTR_ERR(regmap));
> > +             return PTR_ERR(regmap);
> > +     }
> > +
> > +     ret = adxl313_core_probe(&spi->dev, regmap, id->name);
> > +     if (ret < 0)
> > +             return ret;
> > +
> > +     return regmap_update_bits(regmap, ADXL313_REG_POWER_CTL,
> > +                               ADXL313_I2C_DISABLE, ADXL313_I2C_DISABLE);
>
> Why is this only done after the rest of probe?  Needs a comment perhaps.
> Normally I'd expect the core probe and hence exposure of the device
> to userspace etc to be the last thing done.
>
> > +}
> > +
> > +static const struct spi_device_id adxl313_spi_id[] = {
> > +     { "adxl313", 0 },
> > +     { }
> > +};
> > +
> > +MODULE_DEVICE_TABLE(spi, adxl313_spi_id);
> > +
> > +static const struct of_device_id adxl313_of_match[] = {
> > +     { .compatible = "adi,adxl313" },
> > +     { },
> > +};
> > +
> > +MODULE_DEVICE_TABLE(of, adxl313_of_match);
> > +
> > +static struct spi_driver adxl313_spi_driver = {
> > +     .driver = {
> > +             .name   = "adxl313_spi",
> > +             .of_match_table = adxl313_of_match,
> > +     },
> > +     .probe          = adxl313_spi_probe,
> > +     .id_table       = adxl313_spi_id,
> > +};
> > +
> > +module_spi_driver(adxl313_spi_driver);
> > +
> > +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> > +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer SPI driver");
> > +MODULE_LICENSE("GPL v2");
>

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH 2/2] iio: accel: Add driver support for ADXL313
  2021-07-31 20:36 ` [PATCH 2/2] iio: accel: Add driver support " Lucas Stankus
  2021-08-01 18:12   ` Jonathan Cameron
@ 2021-08-02  7:04   ` Alexandru Ardelean
  2021-08-02 17:30     ` Lucas Stankus
  1 sibling, 1 reply; 14+ messages in thread
From: Alexandru Ardelean @ 2021-08-02  7:04 UTC (permalink / raw)
  To: Lucas Stankus
  Cc: Lars-Peter Clausen, Hennerich, Michael, Jonathan Cameron,
	Rob Herring, Bogdan, Dragos, Berghe, Darius, linux-iio,
	devicetree, LKML

On Sat, Jul 31, 2021 at 11:37 PM Lucas Stankus
<lucas.p.stankus@gmail.com> wrote:
>
> ADXL313 is a small, thin, low power, 3-axis accelerometer with high
> resolution measurement up to +/-4g. It includes an integrated 32-level
> FIFO and has activity and inactivity sensing capabilities.
>

I have just one small note to add on top of what Jonathan said, about
the null terminator.
Since this may be getting a V2, I thought it could go in.

> Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
>
> Signed-off-by: Lucas Stankus <lucas.p.stankus@gmail.com>
> ---
>  MAINTAINERS                      |   9 +
>  drivers/iio/accel/Kconfig        |  29 +++
>  drivers/iio/accel/Makefile       |   3 +
>  drivers/iio/accel/adxl313.h      |  60 ++++++
>  drivers/iio/accel/adxl313_core.c | 323 +++++++++++++++++++++++++++++++
>  drivers/iio/accel/adxl313_i2c.c  |  65 +++++++
>  drivers/iio/accel/adxl313_spi.c  |  74 +++++++
>  7 files changed, 563 insertions(+)
>  create mode 100644 drivers/iio/accel/adxl313.h
>  create mode 100644 drivers/iio/accel/adxl313_core.c
>  create mode 100644 drivers/iio/accel/adxl313_i2c.c
>  create mode 100644 drivers/iio/accel/adxl313_spi.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index a61f4f3b78a9..1fc88723e632 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -585,6 +585,15 @@ L: platform-driver-x86@vger.kernel.org
>  S:     Maintained
>  F:     drivers/platform/x86/adv_swbutton.c
>
> +ADXL313 THREE-AXIS DIGITAL ACCELEROMETER DRIVER
> +M:     Lucas Stankus <lucas.p.stankus@gmail.com>
> +S:     Supported
> +F:     Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
> +F:     drivers/iio/accel/adxl313.h
> +F:     drivers/iio/accel/adxl313_core.c
> +F:     drivers/iio/accel/adxl313_i2c.c
> +F:     drivers/iio/accel/adxl313_spi.c
> +
>  ADXL34X THREE-AXIS DIGITAL ACCELEROMETER DRIVER (ADXL345/ADXL346)
>  M:     Michael Hennerich <michael.hennerich@analog.com>
>  S:     Supported
> diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
> index 0e56ace61103..ae621532e716 100644
> --- a/drivers/iio/accel/Kconfig
> +++ b/drivers/iio/accel/Kconfig
> @@ -30,6 +30,35 @@ config ADIS16209
>           To compile this driver as a module, say M here: the module will be
>           called adis16209.
>
> +config ADXL313
> +       tristate
> +
> +config ADXL313_I2C
> +       tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer I2C Driver"
> +       depends on I2C
> +       select ADXL313
> +       select REGMAP_I2C
> +       help
> +         Say Y here if you want to build i2c support for the Analog Devices
> +         ADXL313 3-axis digital accelerometer.
> +
> +         To compile this driver as a module, choose M here: the module
> +         will be called adxl313_i2c and you will also get adxl313_core
> +         for the core module.
> +
> +config ADXL313_SPI
> +       tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer SPI Driver"
> +       depends on SPI
> +       select ADXL313
> +       select REGMAP_SPI
> +       help
> +         Say Y here if you want to build spi support for the Analog Devices
> +         ADXL313 3-axis digital accelerometer.
> +
> +         To compile this driver as a module, choose M here: the module
> +         will be called adxl313_spi and you will also get adxl313_core
> +         for the core module.
> +
>  config ADXL345
>         tristate
>
> diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
> index 89280e823bcd..fadc92816e24 100644
> --- a/drivers/iio/accel/Makefile
> +++ b/drivers/iio/accel/Makefile
> @@ -6,6 +6,9 @@
>  # When adding new entries keep the list in alphabetical order
>  obj-$(CONFIG_ADIS16201) += adis16201.o
>  obj-$(CONFIG_ADIS16209) += adis16209.o
> +obj-$(CONFIG_ADXL313) += adxl313_core.o
> +obj-$(CONFIG_ADXL313_I2C) += adxl313_i2c.o
> +obj-$(CONFIG_ADXL313_SPI) += adxl313_spi.o
>  obj-$(CONFIG_ADXL345) += adxl345_core.o
>  obj-$(CONFIG_ADXL345_I2C) += adxl345_i2c.o
>  obj-$(CONFIG_ADXL345_SPI) += adxl345_spi.o
> diff --git a/drivers/iio/accel/adxl313.h b/drivers/iio/accel/adxl313.h
> new file mode 100644
> index 000000000000..72f268e02a80
> --- /dev/null
> +++ b/drivers/iio/accel/adxl313.h
> @@ -0,0 +1,60 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * ADXL313 3-Axis Digital Accelerometer
> + *
> + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> + */
> +
> +#ifndef _ADXL313_H_
> +#define _ADXL313_H_
> +
> +/* ADXL313 register definitions */
> +#define ADXL313_REG_DEVID0             0x00
> +#define ADXL313_REG_DEVID1             0x01
> +#define ADXL313_REG_PARTID             0x02
> +#define ADXL313_REG_XID                        0x04
> +#define ADXL313_REG_SOFT_RESET         0x18
> +#define ADXL313_REG_OFS_AXIS(index)    (0x1E + (index))
> +#define ADXL313_REG_THRESH_ACT         0x24
> +#define ADXL313_REG_ACT_INACT_CTL      0x27
> +#define ADXL313_REG_BW_RATE            0x2C
> +#define ADXL313_REG_POWER_CTL          0x2D
> +#define ADXL313_REG_INT_MAP            0x2F
> +#define ADXL313_REG_DATA_FORMAT                0x31
> +#define ADXL313_REG_DATAX              0x32
> +#define ADXL313_REG_DATAY              0x34
> +#define ADXL313_REG_DATAZ              0x36
> +#define ADXL313_REG_FIFO_CTL           0x38
> +#define ADXL313_REG_FIFO_STATUS                0x39
> +
> +#define ADXL313_DEVID0                 0xAD
> +#define ADXL313_DEVID1                 0x1D
> +#define ADXL313_PARTID                 0xCB
> +#define ADXL313_SOFT_RESET             0x52
> +
> +#define ADXL313_RATE_MSK               GENMASK(3, 0)
> +#define ADXL313_RATE_BASE              6
> +
> +#define ADXL313_POWER_CTL_MSK          GENMASK(3, 2)
> +#define ADXL313_MEASUREMENT_MODE       BIT(3)
> +
> +#define ADXL313_RANGE_MSK              GENMASK(1, 0)
> +#define ADXL313_RANGE_4G               3
> +
> +#define ADXL313_FULL_RES               BIT(3)
> +#define ADXL313_SPI_3WIRE              BIT(6)
> +#define ADXL313_I2C_DISABLE            BIT(6)
> +
> +/*
> + * Scale for any g range is given in datasheet as
> + * 1024 LSB/g = 0.0009765625 * 9.80665 = 0.009576806640625 m/s^2
> + */
> +#define ADXL313_NSCALE 9576806
> +
> +extern const struct regmap_access_table adxl313_readable_regs_table;
> +
> +extern const struct regmap_access_table adxl313_writable_regs_table;
> +
> +int adxl313_core_probe(struct device *dev, struct regmap *regmap,
> +                      const char *name);
> +#endif /* _ADXL313_H_ */
> diff --git a/drivers/iio/accel/adxl313_core.c b/drivers/iio/accel/adxl313_core.c
> new file mode 100644
> index 000000000000..76382ab4f0f4
> --- /dev/null
> +++ b/drivers/iio/accel/adxl313_core.c
> @@ -0,0 +1,323 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * ADXL313 3-Axis Digital Accelerometer
> + *
> + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> + *
> + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/iio/iio.h>
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +
> +#include "adxl313.h"
> +
> +const struct regmap_range adxl313_readable_reg_range[] = {
> +       regmap_reg_range(ADXL313_REG_DEVID0, ADXL313_REG_XID),
> +       regmap_reg_range(ADXL313_REG_SOFT_RESET, ADXL313_REG_SOFT_RESET),
> +       regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
> +       regmap_reg_range(ADXL313_REG_THRESH_ACT, ADXL313_REG_ACT_INACT_CTL),
> +       regmap_reg_range(ADXL313_REG_BW_RATE, ADXL313_REG_FIFO_STATUS)
> +};
> +
> +const struct regmap_access_table adxl313_readable_regs_table = {
> +       .yes_ranges = adxl313_readable_reg_range,
> +       .n_yes_ranges = ARRAY_SIZE(adxl313_readable_reg_range)
> +};
> +EXPORT_SYMBOL_GPL(adxl313_readable_regs_table);
> +
> +const struct regmap_range adxl313_writable_reg_range[] = {
> +       regmap_reg_range(ADXL313_REG_SOFT_RESET, ADXL313_REG_SOFT_RESET),
> +       regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
> +       regmap_reg_range(ADXL313_REG_THRESH_ACT, ADXL313_REG_ACT_INACT_CTL),
> +       regmap_reg_range(ADXL313_REG_BW_RATE, ADXL313_REG_INT_MAP),
> +       regmap_reg_range(ADXL313_REG_DATA_FORMAT, ADXL313_REG_DATA_FORMAT),
> +       regmap_reg_range(ADXL313_REG_FIFO_CTL, ADXL313_REG_FIFO_CTL)
> +};
> +
> +const struct regmap_access_table adxl313_writable_regs_table = {
> +       .yes_ranges = adxl313_writable_reg_range,
> +       .n_yes_ranges = ARRAY_SIZE(adxl313_writable_reg_range)
> +};
> +EXPORT_SYMBOL_GPL(adxl313_writable_regs_table);
> +
> +struct adxl313_data {
> +       struct regmap   *regmap;
> +       struct mutex    lock; /* lock to protect transf_buf */
> +       __le16          transf_buf ____cacheline_aligned;
> +};
> +
> +static const int adxl313_odr_freqs[][2] = {
> +       [0] = { 6, 250000 },
> +       [1] = { 12, 500000 },
> +       [2] = { 25, 0 },
> +       [3] = { 50, 0 },
> +       [4] = { 100, 0 },
> +       [5] = { 200, 0 },
> +       [6] = { 400, 0 },
> +       [7] = { 800, 0 },
> +       [8] = { 1600, 0 },
> +       [9] = { 3200, 0 },
> +};
> +
> +#define ADXL313_ACCEL_CHANNEL(index, addr, axis) {                     \
> +       .type = IIO_ACCEL,                                              \
> +       .address = addr,                                                \
> +       .modified = 1,                                                  \
> +       .channel2 = IIO_MOD_##axis,                                     \
> +       .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |                  \
> +                             BIT(IIO_CHAN_INFO_CALIBBIAS),             \
> +       .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |          \
> +                                   BIT(IIO_CHAN_INFO_SAMP_FREQ),       \
> +       .info_mask_shared_by_type_available =                           \
> +               BIT(IIO_CHAN_INFO_SAMP_FREQ),                           \
> +       .scan_index = index,                                            \
> +       .scan_type = {                                                  \
> +               .sign = 's',                                            \
> +               .realbits = 13,                                         \
> +               .storagebits = 16,                                      \
> +               .endianness = IIO_LE,                                   \
> +       },                                                              \
> +}
> +
> +static const struct iio_chan_spec adxl313_channels[] = {
> +       ADXL313_ACCEL_CHANNEL(0, ADXL313_REG_DATAX, X),
> +       ADXL313_ACCEL_CHANNEL(1, ADXL313_REG_DATAY, Y),
> +       ADXL313_ACCEL_CHANNEL(2, ADXL313_REG_DATAZ, Z),
> +};
> +
> +static int adxl313_set_odr(struct adxl313_data *data,
> +                          unsigned int freq1, unsigned int freq2)
> +{
> +       unsigned int i;
> +
> +       for (i = 0; i < ARRAY_SIZE(adxl313_odr_freqs); i++) {
> +               if (adxl313_odr_freqs[i][0] == freq1 &&
> +                   adxl313_odr_freqs[i][1] == freq2)
> +                       break;
> +       }
> +
> +       if (i == ARRAY_SIZE(adxl313_odr_freqs))
> +               return -EINVAL;
> +
> +       return regmap_update_bits(data->regmap, ADXL313_REG_BW_RATE,
> +                                 ADXL313_RATE_MSK,
> +                                 FIELD_PREP(ADXL313_RATE_MSK,
> +                                            ADXL313_RATE_BASE + i));
> +}
> +
> +static int adxl313_read_axis(struct adxl313_data *data,
> +                            struct iio_chan_spec const *chan)
> +{
> +       int ret;
> +
> +       mutex_lock(&data->lock);
> +
> +       ret = regmap_bulk_read(data->regmap,
> +                              chan->address,
> +                              &data->transf_buf, 2);
> +       if (ret)
> +               goto unlock_ret;
> +
> +       ret = le16_to_cpu(data->transf_buf);
> +
> +unlock_ret:
> +       mutex_unlock(&data->lock);
> +       return ret;
> +}
> +
> +static int adxl313_read_freq_avail(struct iio_dev *indio_dev,
> +                                  struct iio_chan_spec const *chan,
> +                                  const int **vals, int *type, int *length,
> +                                  long mask)
> +{
> +       switch (mask) {
> +       case IIO_CHAN_INFO_SAMP_FREQ:
> +               *vals = (const int *)adxl313_odr_freqs;
> +               *length = ARRAY_SIZE(adxl313_odr_freqs) * 2;
> +               *type = IIO_VAL_INT_PLUS_MICRO;
> +               return IIO_AVAIL_LIST;
> +       }
> +
> +       return -EINVAL;
> +}
> +
> +static int adxl313_read_raw(struct iio_dev *indio_dev,
> +                           struct iio_chan_spec const *chan,
> +                           int *val, int *val2, long mask)
> +{
> +       struct adxl313_data *data = iio_priv(indio_dev);
> +       unsigned int regval;
> +       int ret;
> +
> +       switch (mask) {
> +       case IIO_CHAN_INFO_RAW:
> +               ret = adxl313_read_axis(data, chan);
> +               if (ret < 0)
> +                       return ret;
> +
> +               *val = sign_extend32(ret, chan->scan_type.realbits - 1);
> +               return IIO_VAL_INT;
> +       case IIO_CHAN_INFO_SCALE:
> +               *val = 0;
> +               *val2 = ADXL313_NSCALE;
> +               return IIO_VAL_INT_PLUS_NANO;
> +       case IIO_CHAN_INFO_CALIBBIAS:
> +               ret = regmap_read(data->regmap,
> +                                 ADXL313_REG_OFS_AXIS(chan->scan_index),
> +                                 &regval);
> +               if (ret)
> +                       return ret;
> +
> +               /*
> +                * 8-bit resolution at +/- 0.5g, that is 4x accel data scale
> +                * factor at full resolution
> +                */
> +               *val = sign_extend32(regval, 7) * 4;
> +               return IIO_VAL_INT;
> +       case IIO_CHAN_INFO_SAMP_FREQ:
> +               ret = regmap_read(data->regmap, ADXL313_REG_BW_RATE, &regval);
> +               if (ret)
> +                       return ret;
> +
> +               ret = FIELD_GET(ADXL313_RATE_MSK, regval) - ADXL313_RATE_BASE;
> +               *val = adxl313_odr_freqs[ret][0];
> +               *val2 = adxl313_odr_freqs[ret][1];
> +               return IIO_VAL_INT_PLUS_MICRO;
> +       }
> +
> +       return -EINVAL;
> +}
> +
> +static int adxl313_write_raw(struct iio_dev *indio_dev,
> +                            struct iio_chan_spec const *chan,
> +                            int val, int val2, long mask)
> +{
> +       struct adxl313_data *data = iio_priv(indio_dev);
> +
> +       switch (mask) {
> +       case IIO_CHAN_INFO_CALIBBIAS:
> +               /*
> +                * 8-bit resolution at +/- 0.5g, that is 4x accel data scale
> +                * factor at full resolution
> +                */
> +               if (val > 127 * 4 || val < -128 * 4)
> +                       return -EINVAL;
> +
> +               return regmap_write(data->regmap,
> +                                   ADXL313_REG_OFS_AXIS(chan->scan_index),
> +                                   val / 4);
> +       case IIO_CHAN_INFO_SAMP_FREQ:
> +               return adxl313_set_odr(data, val, val2);
> +       }
> +
> +       return -EINVAL;
> +}
> +
> +static const struct iio_info adxl313_info = {
> +       .read_raw       = adxl313_read_raw,
> +       .write_raw      = adxl313_write_raw,
> +       .read_avail     = adxl313_read_freq_avail
> +};
> +
> +static int adxl313_setup(struct device *dev, struct adxl313_data *data)
> +{
> +       unsigned int regval;
> +       int ret;
> +
> +       /* Ensures the device is in a consistent state after start up */
> +       ret = regmap_write(data->regmap, ADXL313_REG_SOFT_RESET,
> +                          ADXL313_SOFT_RESET);
> +       if (ret)
> +               return ret;
> +
> +       if (device_property_read_bool(dev, "spi-3wire")) {
> +               ret = regmap_write(data->regmap, ADXL313_REG_DATA_FORMAT,
> +                                  ADXL313_SPI_3WIRE);
> +               if (ret)
> +                       return ret;
> +       }
> +
> +       ret = regmap_read(data->regmap, ADXL313_REG_DEVID0, &regval);
> +       if (ret)
> +               return ret;
> +
> +       if (regval != ADXL313_DEVID0) {
> +               dev_err(dev, "Invalid manufacturer ID: 0x%02x\n", regval);
> +               return -ENODEV;
> +       }
> +
> +       ret = regmap_read(data->regmap, ADXL313_REG_DEVID1, &regval);
> +       if (ret)
> +               return ret;
> +
> +       if (regval != ADXL313_DEVID1) {
> +               dev_err(dev, "Invalid mems ID: 0x%02x\n", regval);
> +               return -ENODEV;
> +       }
> +
> +       ret = regmap_read(data->regmap, ADXL313_REG_PARTID, &regval);
> +       if (ret)
> +               return ret;
> +
> +       if (regval != ADXL313_PARTID) {
> +               dev_err(dev, "Invalid device ID: 0x%02x\n", regval);
> +               return -ENODEV;
> +       }
> +
> +       /* Sets the range to +/- 4g */
> +       ret = regmap_update_bits(data->regmap, ADXL313_REG_DATA_FORMAT,
> +                                ADXL313_RANGE_MSK,
> +                                FIELD_PREP(ADXL313_RANGE_MSK,
> +                                           ADXL313_RANGE_4G));
> +       if (ret)
> +               return ret;
> +
> +       /* Enables full resolution */
> +       ret = regmap_update_bits(data->regmap, ADXL313_REG_DATA_FORMAT,
> +                                ADXL313_FULL_RES, ADXL313_FULL_RES);
> +       if (ret)
> +               return ret;
> +
> +       /* Enables measurement mode */
> +       return regmap_update_bits(data->regmap, ADXL313_REG_POWER_CTL,
> +                                 ADXL313_POWER_CTL_MSK,
> +                                 ADXL313_MEASUREMENT_MODE);
> +}
> +
> +int adxl313_core_probe(struct device *dev, struct regmap *regmap,
> +                      const char *name)
> +{
> +       struct adxl313_data *data;
> +       struct iio_dev *indio_dev;
> +       int ret;
> +
> +       indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
> +       if (!indio_dev)
> +               return -ENOMEM;
> +
> +       data = iio_priv(indio_dev);
> +       data->regmap = regmap;
> +       mutex_init(&data->lock);
> +
> +       indio_dev->name = name;
> +       indio_dev->info = &adxl313_info;
> +       indio_dev->modes = INDIO_DIRECT_MODE;
> +       indio_dev->channels = adxl313_channels;
> +       indio_dev->num_channels = ARRAY_SIZE(adxl313_channels);
> +
> +       ret = adxl313_setup(dev, data);
> +       if (ret) {
> +               dev_err(dev, "ADXL313 setup failed\n");
> +               return ret;
> +       }
> +
> +       return devm_iio_device_register(dev, indio_dev);
> +}
> +EXPORT_SYMBOL_GPL(adxl313_core_probe);
> +
> +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer core driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/iio/accel/adxl313_i2c.c b/drivers/iio/accel/adxl313_i2c.c
> new file mode 100644
> index 000000000000..65050a2fbd38
> --- /dev/null
> +++ b/drivers/iio/accel/adxl313_i2c.c
> @@ -0,0 +1,65 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * ADXL313 3-Axis Digital Accelerometer
> + *
> + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> + *
> + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> + */
> +
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +
> +#include "adxl313.h"
> +
> +static const struct regmap_config adxl313_i2c_regmap_config = {
> +       .reg_bits       = 8,
> +       .val_bits       = 8,
> +       .rd_table       = &adxl313_readable_regs_table,
> +       .wr_table       = &adxl313_writable_regs_table,
> +       .max_register   = 0x39
> +};
> +
> +static int adxl313_i2c_probe(struct i2c_client *client)
> +{
> +       struct regmap *regmap;
> +
> +       regmap = devm_regmap_init_i2c(client, &adxl313_i2c_regmap_config);
> +       if (IS_ERR(regmap)) {
> +               dev_err(&client->dev, "Error initializing i2c regmap: %ld\n",
> +                       PTR_ERR(regmap));
> +               return PTR_ERR(regmap);
> +       }
> +
> +       return adxl313_core_probe(&client->dev, regmap, client->name);
> +}
> +
> +static const struct i2c_device_id adxl313_i2c_id[] = {
> +       { "adxl313", 0 },
> +       { }
> +};
> +
> +MODULE_DEVICE_TABLE(i2c, adxl313_i2c_id);
> +
> +static const struct of_device_id adxl313_of_match[] = {
> +       { .compatible = "adi,adxl313" },
> +       { },

Since this may be getting a V2 anyway, maybe remove the comma from the
null-terminators [where the case].

> +};
> +
> +MODULE_DEVICE_TABLE(of, adxl313_of_match);
> +
> +static struct i2c_driver adxl313_i2c_driver = {
> +       .driver = {
> +               .name   = "adxl313_i2c",
> +               .of_match_table = adxl313_of_match,
> +       },
> +       .probe_new      = adxl313_i2c_probe,
> +       .id_table       = adxl313_i2c_id,
> +};
> +
> +module_i2c_driver(adxl313_i2c_driver);
> +
> +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer I2C driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/iio/accel/adxl313_spi.c b/drivers/iio/accel/adxl313_spi.c
> new file mode 100644
> index 000000000000..7c58c9ff8985
> --- /dev/null
> +++ b/drivers/iio/accel/adxl313_spi.c
> @@ -0,0 +1,74 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * ADXL313 3-Axis Digital Accelerometer
> + *
> + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> + *
> + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> + */
> +
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +#include <linux/spi/spi.h>
> +
> +#include "adxl313.h"
> +
> +static const struct regmap_config adxl313_spi_regmap_config = {
> +       .reg_bits       = 8,
> +       .val_bits       = 8,
> +       .rd_table       = &adxl313_readable_regs_table,
> +       .wr_table       = &adxl313_writable_regs_table,
> +       .max_register   = 0x39,
> +        /* Setting bits 7 and 6 enables multiple-byte read */
> +       .read_flag_mask = BIT(7) | BIT(6)
> +};
> +
> +static int adxl313_spi_probe(struct spi_device *spi)
> +{
> +       const struct spi_device_id *id = spi_get_device_id(spi);
> +       struct regmap *regmap;
> +       int ret;
> +
> +       regmap = devm_regmap_init_spi(spi, &adxl313_spi_regmap_config);
> +       if (IS_ERR(regmap)) {
> +               dev_err(&spi->dev, "Error initializing spi regmap: %ld\n",
> +                       PTR_ERR(regmap));
> +               return PTR_ERR(regmap);
> +       }
> +
> +       ret = adxl313_core_probe(&spi->dev, regmap, id->name);
> +       if (ret < 0)
> +               return ret;
> +
> +       return regmap_update_bits(regmap, ADXL313_REG_POWER_CTL,
> +                                 ADXL313_I2C_DISABLE, ADXL313_I2C_DISABLE);
> +}
> +
> +static const struct spi_device_id adxl313_spi_id[] = {
> +       { "adxl313", 0 },
> +       { }
> +};
> +
> +MODULE_DEVICE_TABLE(spi, adxl313_spi_id);
> +
> +static const struct of_device_id adxl313_of_match[] = {
> +       { .compatible = "adi,adxl313" },
> +       { },
> +};
> +
> +MODULE_DEVICE_TABLE(of, adxl313_of_match);
> +
> +static struct spi_driver adxl313_spi_driver = {
> +       .driver = {
> +               .name   = "adxl313_spi",
> +               .of_match_table = adxl313_of_match,
> +       },
> +       .probe          = adxl313_spi_probe,
> +       .id_table       = adxl313_spi_id,
> +};
> +
> +module_spi_driver(adxl313_spi_driver);
> +
> +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer SPI driver");
> +MODULE_LICENSE("GPL v2");
> --
> 2.32.0
>

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH 1/2] dt-bindings: iio: accel: Add binding documentation for ADXL313
  2021-07-31 20:36 ` [PATCH 1/2] dt-bindings: iio: accel: Add binding documentation for ADXL313 Lucas Stankus
  2021-08-01 18:04   ` Jonathan Cameron
@ 2021-08-02 13:39   ` Rob Herring
  1 sibling, 0 replies; 14+ messages in thread
From: Rob Herring @ 2021-08-02 13:39 UTC (permalink / raw)
  To: Lucas Stankus
  Cc: Dragos.Bogdan, robh+dt, linux-iio, lars, Darius.Berghe,
	Michael.Hennerich, devicetree, jic23, linux-kernel

On Sat, 31 Jul 2021 17:36:31 -0300, Lucas Stankus wrote:
> Add device tree binding documentation for ADXL313 3-axis accelerometer.
> 
> Signed-off-by: Lucas Stankus <lucas.p.stankus@gmail.com>
> ---
>  .../bindings/iio/accel/adi,adxl313.yaml       | 75 +++++++++++++++++++
>  1 file changed, 75 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
> 

My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
on your patch (DT_CHECKER_FLAGS is new in v5.13):

yamllint warnings/errors:

dtschema/dtc warnings/errors:
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/iio/accel/adi,adxl313.example.dt.yaml: accelerometer@53: interrupts: [[0, 4]] is too short
	From schema: /builds/robherring/linux-dt-review/Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/iio/accel/adi,adxl313.example.dt.yaml: accelerometer@0: interrupts: [[0, 4]] is too short
	From schema: /builds/robherring/linux-dt-review/Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
\ndoc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/patch/1511954

This check can fail if there are any dependencies. The base for a patch
series is generally the most recent rc1.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit.


^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH 1/2] dt-bindings: iio: accel: Add binding documentation for ADXL313
  2021-08-01 18:04   ` Jonathan Cameron
@ 2021-08-02 16:49     ` Lucas Stankus
  0 siblings, 0 replies; 14+ messages in thread
From: Lucas Stankus @ 2021-08-02 16:49 UTC (permalink / raw)
  To: Jonathan Cameron
  Cc: Lars-Peter Clausen, Hennerich, Michael, robh+dt, Bogdan, Dragos,
	Berghe, Darius, linux-iio, devicetree, Linux Kernel Mailing List

On Sun, Aug 1, 2021 at 3:01 PM Jonathan Cameron <jic23@kernel.org> wrote:
>
> On Sat, 31 Jul 2021 17:36:31 -0300
> Lucas Stankus <lucas.p.stankus@gmail.com> wrote:
>
> > Add device tree binding documentation for ADXL313 3-axis accelerometer.
> >
> > Signed-off-by: Lucas Stankus <lucas.p.stankus@gmail.com>
>
> Hi Lucas,
>
> A few minor requests for additions inline, so we include everything
> that is likely to be used by the driver in the longer term.
>
> > ---
> >  .../bindings/iio/accel/adi,adxl313.yaml       | 75 +++++++++++++++++++
> >  1 file changed, 75 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml b/Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
> > new file mode 100644
> > index 000000000000..31f11d7eaaae
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
> > @@ -0,0 +1,75 @@
> > +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/iio/accel/adi,adxl313.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Analog Devices ADXL313 3-Axis Digital Accelerometer
> > +
> > +maintainers:
> > +  - Lucas Stankus <lucas.p.stankus@gmail.com>
> > +
> > +description: |
> > +  Analog Devices ADXL313 3-Axis Digital Accelerometer that supports
> > +  both I2C & SPI interfaces.
> > +    https://www.analog.com/en/products/adxl313.html
> > +
> > +properties:
> > +  compatible:
> > +    enum:
> > +      - adi,adxl313
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  spi-3wire: true
> > +
> > +  spi-cpha: true
> > +
> > +  spi-cpol: true
> > +
> > +  spi-max-frequency: true
> > +
> > +  interrupts:
> > +    maxItems: 2
>
> As board designers have an annoying habit of wiring up the second
> interrupt only, please also provide interrupt-names so we can
> know which one is connected if it's only one.
>
> From a quick glance at the datasheet, I see this also has two powersupplies.
> Please include
> vddio-supply
> vs-supply - annoyingly the s just stands for supply, but v-supply seems a bit to minimal.
>

Thanks for the feedback, I'll change it for the v2!

> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +
> > +additionalProperties: false
> > +
> > +examples:
> > +  - |
> > +    #include <dt-bindings/gpio/gpio.h>
> > +    #include <dt-bindings/interrupt-controller/irq.h>
> > +    i2c0 {
> > +        #address-cells = <1>;
> > +        #size-cells = <0>;
> > +
> > +        /* Example for a I2C device node */
> > +        accelerometer@53 {
> > +            compatible = "adi,adxl313";
> > +            reg = <0x53>;
> > +            interrupt-parent = <&gpio0>;
> > +            interrupts = <0 IRQ_TYPE_LEVEL_HIGH>;
> > +        };
> > +    };
> > +  - |
> > +    #include <dt-bindings/gpio/gpio.h>
> > +    #include <dt-bindings/interrupt-controller/irq.h>
> > +    spi {
> > +        #address-cells = <1>;
> > +        #size-cells = <0>;
> > +
> > +        /* Example for a SPI device node */
> > +        accelerometer@0 {
> > +            compatible = "adi,adxl313";
> > +            reg = <0>;
> > +            spi-max-frequency = <5000000>;
> > +            spi-cpol;
> > +            spi-cpha;
> > +            interrupt-parent = <&gpio0>;
> > +            interrupts = <0 IRQ_TYPE_LEVEL_HIGH>;
> > +        };
> > +    };
>

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH 2/2] iio: accel: Add driver support for ADXL313
  2021-08-01 18:12   ` Jonathan Cameron
  2021-08-02  6:57     ` Alexandru Ardelean
@ 2021-08-02 17:15     ` Lucas Stankus
  2021-08-03 17:18       ` Jonathan Cameron
  1 sibling, 1 reply; 14+ messages in thread
From: Lucas Stankus @ 2021-08-02 17:15 UTC (permalink / raw)
  To: Jonathan Cameron
  Cc: Lars-Peter Clausen, Hennerich, Michael, robh+dt, Bogdan, Dragos,
	Berghe, Darius, linux-iio, devicetree, Linux Kernel Mailing List

On Sun, Aug 1, 2021 at 3:09 PM Jonathan Cameron <jic23@kernel.org> wrote:
>
> On Sat, 31 Jul 2021 17:36:48 -0300
> Lucas Stankus <lucas.p.stankus@gmail.com> wrote:
>
> > ADXL313 is a small, thin, low power, 3-axis accelerometer with high
> > resolution measurement up to +/-4g. It includes an integrated 32-level
> > FIFO and has activity and inactivity sensing capabilities.
> >
> > Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> >
> > Signed-off-by: Lucas Stankus <lucas.p.stankus@gmail.com>
>
> Very nice.  A few really minor things inline.
>
> Jonathan
>

Thanks for the feedback!

I'll change the minor things for the v2.

> > ---
> >  MAINTAINERS                      |   9 +
> >  drivers/iio/accel/Kconfig        |  29 +++
> >  drivers/iio/accel/Makefile       |   3 +
> >  drivers/iio/accel/adxl313.h      |  60 ++++++
> >  drivers/iio/accel/adxl313_core.c | 323 +++++++++++++++++++++++++++++++
> >  drivers/iio/accel/adxl313_i2c.c  |  65 +++++++
> >  drivers/iio/accel/adxl313_spi.c  |  74 +++++++
> >  7 files changed, 563 insertions(+)
> >  create mode 100644 drivers/iio/accel/adxl313.h
> >  create mode 100644 drivers/iio/accel/adxl313_core.c
> >  create mode 100644 drivers/iio/accel/adxl313_i2c.c
> >  create mode 100644 drivers/iio/accel/adxl313_spi.c
> >
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index a61f4f3b78a9..1fc88723e632 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -585,6 +585,15 @@ L:       platform-driver-x86@vger.kernel.org
> >  S:   Maintained
> >  F:   drivers/platform/x86/adv_swbutton.c
> >
> > +ADXL313 THREE-AXIS DIGITAL ACCELEROMETER DRIVER
> > +M:   Lucas Stankus <lucas.p.stankus@gmail.com>
> > +S:   Supported
> > +F:   Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
> > +F:   drivers/iio/accel/adxl313.h
> > +F:   drivers/iio/accel/adxl313_core.c
> > +F:   drivers/iio/accel/adxl313_i2c.c
> > +F:   drivers/iio/accel/adxl313_spi.c
> > +
> >  ADXL34X THREE-AXIS DIGITAL ACCELEROMETER DRIVER (ADXL345/ADXL346)
> >  M:   Michael Hennerich <michael.hennerich@analog.com>
> >  S:   Supported
> > diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
> > index 0e56ace61103..ae621532e716 100644
> > --- a/drivers/iio/accel/Kconfig
> > +++ b/drivers/iio/accel/Kconfig
> > @@ -30,6 +30,35 @@ config ADIS16209
> >         To compile this driver as a module, say M here: the module will be
> >         called adis16209.
> >
> > +config ADXL313
> > +     tristate
> > +
> > +config ADXL313_I2C
> > +     tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer I2C Driver"
> > +     depends on I2C
> > +     select ADXL313
> > +     select REGMAP_I2C
> > +     help
> > +       Say Y here if you want to build i2c support for the Analog Devices
> > +       ADXL313 3-axis digital accelerometer.
> > +
> > +       To compile this driver as a module, choose M here: the module
> > +       will be called adxl313_i2c and you will also get adxl313_core
> > +       for the core module.
> > +
> > +config ADXL313_SPI
> > +     tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer SPI Driver"
> > +     depends on SPI
> > +     select ADXL313
> > +     select REGMAP_SPI
> > +     help
> > +       Say Y here if you want to build spi support for the Analog Devices
> > +       ADXL313 3-axis digital accelerometer.
> > +
> > +       To compile this driver as a module, choose M here: the module
> > +       will be called adxl313_spi and you will also get adxl313_core
> > +       for the core module.
> > +
> >  config ADXL345
> >       tristate
> >
> > diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
> > index 89280e823bcd..fadc92816e24 100644
> > --- a/drivers/iio/accel/Makefile
> > +++ b/drivers/iio/accel/Makefile
> > @@ -6,6 +6,9 @@
> >  # When adding new entries keep the list in alphabetical order
> >  obj-$(CONFIG_ADIS16201) += adis16201.o
> >  obj-$(CONFIG_ADIS16209) += adis16209.o
> > +obj-$(CONFIG_ADXL313) += adxl313_core.o
> > +obj-$(CONFIG_ADXL313_I2C) += adxl313_i2c.o
> > +obj-$(CONFIG_ADXL313_SPI) += adxl313_spi.o
> >  obj-$(CONFIG_ADXL345) += adxl345_core.o
> >  obj-$(CONFIG_ADXL345_I2C) += adxl345_i2c.o
> >  obj-$(CONFIG_ADXL345_SPI) += adxl345_spi.o
> > diff --git a/drivers/iio/accel/adxl313.h b/drivers/iio/accel/adxl313.h
> > new file mode 100644
> > index 000000000000..72f268e02a80
> > --- /dev/null
> > +++ b/drivers/iio/accel/adxl313.h
> > @@ -0,0 +1,60 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +/*
> > + * ADXL313 3-Axis Digital Accelerometer
> > + *
> > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > + */
> > +
> > +#ifndef _ADXL313_H_
> > +#define _ADXL313_H_
> > +
> > +/* ADXL313 register definitions */
>
> If these are only used in the c file, push them down there. Better to
> keep what is in the header to absolute minimum.
> however I suggest below moving some of this so that won't be true any more,
> so maybe you do want to keep them here!
>

Only some of them would be called from the _spi.c file, but I think
I'll keep them here to have them all at the same place.

>
> > +#define ADXL313_REG_DEVID0           0x00
> > +#define ADXL313_REG_DEVID1           0x01
> > +#define ADXL313_REG_PARTID           0x02
> > +#define ADXL313_REG_XID                      0x04
> > +#define ADXL313_REG_SOFT_RESET               0x18
> > +#define ADXL313_REG_OFS_AXIS(index)  (0x1E + (index))
> > +#define ADXL313_REG_THRESH_ACT               0x24
> > +#define ADXL313_REG_ACT_INACT_CTL    0x27
> > +#define ADXL313_REG_BW_RATE          0x2C
> > +#define ADXL313_REG_POWER_CTL                0x2D
> > +#define ADXL313_REG_INT_MAP          0x2F
> > +#define ADXL313_REG_DATA_FORMAT              0x31
> > +#define ADXL313_REG_DATAX            0x32
> > +#define ADXL313_REG_DATAY            0x34
> > +#define ADXL313_REG_DATAZ            0x36
> > +#define ADXL313_REG_FIFO_CTL         0x38
> > +#define ADXL313_REG_FIFO_STATUS              0x39
> > +
> > +#define ADXL313_DEVID0                       0xAD
> > +#define ADXL313_DEVID1                       0x1D
> > +#define ADXL313_PARTID                       0xCB
> > +#define ADXL313_SOFT_RESET           0x52
> > +
> > +#define ADXL313_RATE_MSK             GENMASK(3, 0)
> > +#define ADXL313_RATE_BASE            6
> > +
> > +#define ADXL313_POWER_CTL_MSK                GENMASK(3, 2)
> > +#define ADXL313_MEASUREMENT_MODE     BIT(3)
> > +
> > +#define ADXL313_RANGE_MSK            GENMASK(1, 0)
> > +#define ADXL313_RANGE_4G             3
> > +
> > +#define ADXL313_FULL_RES             BIT(3)
> > +#define ADXL313_SPI_3WIRE            BIT(6)
> > +#define ADXL313_I2C_DISABLE          BIT(6)
> > +
> > +/*
> > + * Scale for any g range is given in datasheet as
> > + * 1024 LSB/g = 0.0009765625 * 9.80665 = 0.009576806640625 m/s^2
> > + */
> > +#define ADXL313_NSCALE 9576806
> > +
> > +extern const struct regmap_access_table adxl313_readable_regs_table;
> > +
> > +extern const struct regmap_access_table adxl313_writable_regs_table;
> > +
> > +int adxl313_core_probe(struct device *dev, struct regmap *regmap,
> > +                    const char *name);
> > +#endif /* _ADXL313_H_ */
> > diff --git a/drivers/iio/accel/adxl313_core.c b/drivers/iio/accel/adxl313_core.c
> > new file mode 100644
> > index 000000000000..76382ab4f0f4
> > --- /dev/null
> > +++ b/drivers/iio/accel/adxl313_core.c
> > @@ -0,0 +1,323 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * ADXL313 3-Axis Digital Accelerometer
> > + *
> > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > + *
> > + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > + */
> > +
> > +#include <linux/bitfield.h>
> > +#include <linux/iio/iio.h>
> > +#include <linux/module.h>
> > +#include <linux/regmap.h>
> > +
> > +#include "adxl313.h"
> > +
> > +const struct regmap_range adxl313_readable_reg_range[] = {
> > +     regmap_reg_range(ADXL313_REG_DEVID0, ADXL313_REG_XID),
> > +     regmap_reg_range(ADXL313_REG_SOFT_RESET, ADXL313_REG_SOFT_RESET),
> > +     regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
> > +     regmap_reg_range(ADXL313_REG_THRESH_ACT, ADXL313_REG_ACT_INACT_CTL),
> > +     regmap_reg_range(ADXL313_REG_BW_RATE, ADXL313_REG_FIFO_STATUS)
> > +};
> > +
> > +const struct regmap_access_table adxl313_readable_regs_table = {
> > +     .yes_ranges = adxl313_readable_reg_range,
> > +     .n_yes_ranges = ARRAY_SIZE(adxl313_readable_reg_range)
> > +};
> > +EXPORT_SYMBOL_GPL(adxl313_readable_regs_table);
> > +
> > +const struct regmap_range adxl313_writable_reg_range[] = {
> > +     regmap_reg_range(ADXL313_REG_SOFT_RESET, ADXL313_REG_SOFT_RESET),
> > +     regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
> > +     regmap_reg_range(ADXL313_REG_THRESH_ACT, ADXL313_REG_ACT_INACT_CTL),
> > +     regmap_reg_range(ADXL313_REG_BW_RATE, ADXL313_REG_INT_MAP),
> > +     regmap_reg_range(ADXL313_REG_DATA_FORMAT, ADXL313_REG_DATA_FORMAT),
> > +     regmap_reg_range(ADXL313_REG_FIFO_CTL, ADXL313_REG_FIFO_CTL)
> > +};
> > +
> > +const struct regmap_access_table adxl313_writable_regs_table = {
> > +     .yes_ranges = adxl313_writable_reg_range,
> > +     .n_yes_ranges = ARRAY_SIZE(adxl313_writable_reg_range)
> > +};
> > +EXPORT_SYMBOL_GPL(adxl313_writable_regs_table);
> > +
> > +struct adxl313_data {
> > +     struct regmap   *regmap;
> > +     struct mutex    lock; /* lock to protect transf_buf */
> > +     __le16          transf_buf ____cacheline_aligned;
> > +};
> > +
> > +static const int adxl313_odr_freqs[][2] = {
> > +     [0] = { 6, 250000 },
> > +     [1] = { 12, 500000 },
> > +     [2] = { 25, 0 },
> > +     [3] = { 50, 0 },
> > +     [4] = { 100, 0 },
> > +     [5] = { 200, 0 },
> > +     [6] = { 400, 0 },
> > +     [7] = { 800, 0 },
> > +     [8] = { 1600, 0 },
> > +     [9] = { 3200, 0 },
> > +};
> > +
> > +#define ADXL313_ACCEL_CHANNEL(index, addr, axis) {                   \
> > +     .type = IIO_ACCEL,                                              \
> > +     .address = addr,                                                \
> > +     .modified = 1,                                                  \
> > +     .channel2 = IIO_MOD_##axis,                                     \
> > +     .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |                  \
> > +                           BIT(IIO_CHAN_INFO_CALIBBIAS),             \
> > +     .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |          \
> > +                                 BIT(IIO_CHAN_INFO_SAMP_FREQ),       \
> > +     .info_mask_shared_by_type_available =                           \
> > +             BIT(IIO_CHAN_INFO_SAMP_FREQ),                           \
> > +     .scan_index = index,                                            \
> > +     .scan_type = {                                                  \
> > +             .sign = 's',                                            \
> > +             .realbits = 13,                                         \
> > +             .storagebits = 16,                                      \
> > +             .endianness = IIO_LE,                                   \
> > +     },                                                              \
> > +}
> > +
> > +static const struct iio_chan_spec adxl313_channels[] = {
> > +     ADXL313_ACCEL_CHANNEL(0, ADXL313_REG_DATAX, X),
> > +     ADXL313_ACCEL_CHANNEL(1, ADXL313_REG_DATAY, Y),
> > +     ADXL313_ACCEL_CHANNEL(2, ADXL313_REG_DATAZ, Z),
> > +};
> > +
> > +static int adxl313_set_odr(struct adxl313_data *data,
> > +                        unsigned int freq1, unsigned int freq2)
> > +{
> > +     unsigned int i;
> > +
> > +     for (i = 0; i < ARRAY_SIZE(adxl313_odr_freqs); i++) {
> > +             if (adxl313_odr_freqs[i][0] == freq1 &&
> > +                 adxl313_odr_freqs[i][1] == freq2)
> > +                     break;
> > +     }
> > +
> > +     if (i == ARRAY_SIZE(adxl313_odr_freqs))
> > +             return -EINVAL;
> > +
> > +     return regmap_update_bits(data->regmap, ADXL313_REG_BW_RATE,
> > +                               ADXL313_RATE_MSK,
> > +                               FIELD_PREP(ADXL313_RATE_MSK,
> > +                                          ADXL313_RATE_BASE + i));
> > +}
> > +
> > +static int adxl313_read_axis(struct adxl313_data *data,
> > +                          struct iio_chan_spec const *chan)
> > +{
> > +     int ret;
> > +
> > +     mutex_lock(&data->lock);
> > +
> > +     ret = regmap_bulk_read(data->regmap,
> > +                            chan->address,
> > +                            &data->transf_buf, 2);
> > +     if (ret)
> > +             goto unlock_ret;
> > +
> > +     ret = le16_to_cpu(data->transf_buf);
> > +
> > +unlock_ret:
> > +     mutex_unlock(&data->lock);
> > +     return ret;
> > +}
> > +
> > +static int adxl313_read_freq_avail(struct iio_dev *indio_dev,
> > +                                struct iio_chan_spec const *chan,
> > +                                const int **vals, int *type, int *length,
> > +                                long mask)
> > +{
> > +     switch (mask) {
> > +     case IIO_CHAN_INFO_SAMP_FREQ:
> > +             *vals = (const int *)adxl313_odr_freqs;
> > +             *length = ARRAY_SIZE(adxl313_odr_freqs) * 2;
> > +             *type = IIO_VAL_INT_PLUS_MICRO;
> > +             return IIO_AVAIL_LIST;
> > +     }
> > +
> > +     return -EINVAL;
> > +}
> > +
> > +static int adxl313_read_raw(struct iio_dev *indio_dev,
> > +                         struct iio_chan_spec const *chan,
> > +                         int *val, int *val2, long mask)
> > +{
> > +     struct adxl313_data *data = iio_priv(indio_dev);
> > +     unsigned int regval;
> > +     int ret;
> > +
> > +     switch (mask) {
> > +     case IIO_CHAN_INFO_RAW:
> > +             ret = adxl313_read_axis(data, chan);
> > +             if (ret < 0)
> > +                     return ret;
> > +
> > +             *val = sign_extend32(ret, chan->scan_type.realbits - 1);
> > +             return IIO_VAL_INT;
> > +     case IIO_CHAN_INFO_SCALE:
> > +             *val = 0;
> > +             *val2 = ADXL313_NSCALE;
> > +             return IIO_VAL_INT_PLUS_NANO;
> > +     case IIO_CHAN_INFO_CALIBBIAS:
> > +             ret = regmap_read(data->regmap,
> > +                               ADXL313_REG_OFS_AXIS(chan->scan_index),
> > +                               &regval);
> > +             if (ret)
> > +                     return ret;
> > +
> > +             /*
> > +              * 8-bit resolution at +/- 0.5g, that is 4x accel data scale
> > +              * factor at full resolution
> > +              */
> > +             *val = sign_extend32(regval, 7) * 4;
> > +             return IIO_VAL_INT;
> > +     case IIO_CHAN_INFO_SAMP_FREQ:
> > +             ret = regmap_read(data->regmap, ADXL313_REG_BW_RATE, &regval);
> > +             if (ret)
> > +                     return ret;
> > +
> > +             ret = FIELD_GET(ADXL313_RATE_MSK, regval) - ADXL313_RATE_BASE;
> > +             *val = adxl313_odr_freqs[ret][0];
> > +             *val2 = adxl313_odr_freqs[ret][1];
> > +             return IIO_VAL_INT_PLUS_MICRO;
> > +     }
> > +
> > +     return -EINVAL;
> > +}
> > +
> > +static int adxl313_write_raw(struct iio_dev *indio_dev,
> > +                          struct iio_chan_spec const *chan,
> > +                          int val, int val2, long mask)
> > +{
> > +     struct adxl313_data *data = iio_priv(indio_dev);
> > +
> > +     switch (mask) {
> > +     case IIO_CHAN_INFO_CALIBBIAS:
> > +             /*
> > +              * 8-bit resolution at +/- 0.5g, that is 4x accel data scale
> > +              * factor at full resolution
> > +              */
> > +             if (val > 127 * 4 || val < -128 * 4)
> > +                     return -EINVAL;
> > +
> > +             return regmap_write(data->regmap,
> > +                                 ADXL313_REG_OFS_AXIS(chan->scan_index),
> > +                                 val / 4);
> > +     case IIO_CHAN_INFO_SAMP_FREQ:
> > +             return adxl313_set_odr(data, val, val2);
> > +     }
> > +
> > +     return -EINVAL;
>
> Put this as a default in the case otherwise you might get warnings saying you
> don't handle all the possible values.
>
> > +}
> > +
> > +static const struct iio_info adxl313_info = {
> > +     .read_raw       = adxl313_read_raw,
> > +     .write_raw      = adxl313_write_raw,
> > +     .read_avail     = adxl313_read_freq_avail
> > +};
> > +
> > +static int adxl313_setup(struct device *dev, struct adxl313_data *data)
> > +{
> > +     unsigned int regval;
> > +     int ret;
> > +
> > +     /* Ensures the device is in a consistent state after start up */
> > +     ret = regmap_write(data->regmap, ADXL313_REG_SOFT_RESET,
> > +                        ADXL313_SOFT_RESET);
> > +     if (ret)
> > +             return ret;
> > +
> > +     if (device_property_read_bool(dev, "spi-3wire")) {
>
> Rather odd to see spi specific stuff in here.  Perhaps provide a callback to
> common probe if it needs to be done at this point in bringing the device up.
> However, I think you can just do this before calling the common_probe()
>

I'm doing this here because of the device reset, so whatever I write
to the register before it would be overwritten in setup. The datasheet
doesn't say that resetting the device is strictly necessary, but I
figured it would be better to do so to force consistency.

If I drop the reset, I'd be able to do it before the core probe call
and, from what I'm seeing here, the startup seems to be consistent
without it. Do you think it's best to drop the device reset?

> > +             ret = regmap_write(data->regmap, ADXL313_REG_DATA_FORMAT,
> > +                                ADXL313_SPI_3WIRE);
> > +             if (ret)
> > +                     return ret;
> > +     }
> > +
> > +     ret = regmap_read(data->regmap, ADXL313_REG_DEVID0, &regval);
> > +     if (ret)
> > +             return ret;
> > +
> > +     if (regval != ADXL313_DEVID0) {
> > +             dev_err(dev, "Invalid manufacturer ID: 0x%02x\n", regval);
> > +             return -ENODEV;
> > +     }
> > +
> > +     ret = regmap_read(data->regmap, ADXL313_REG_DEVID1, &regval);
> > +     if (ret)
> > +             return ret;
> > +
> > +     if (regval != ADXL313_DEVID1) {
> > +             dev_err(dev, "Invalid mems ID: 0x%02x\n", regval);
> > +             return -ENODEV;
> > +     }
> > +
> > +     ret = regmap_read(data->regmap, ADXL313_REG_PARTID, &regval);
> > +     if (ret)
> > +             return ret;
> > +
> > +     if (regval != ADXL313_PARTID) {
> > +             dev_err(dev, "Invalid device ID: 0x%02x\n", regval);
> > +             return -ENODEV;
> > +     }
> > +
> > +     /* Sets the range to +/- 4g */
> > +     ret = regmap_update_bits(data->regmap, ADXL313_REG_DATA_FORMAT,
> > +                              ADXL313_RANGE_MSK,
> > +                              FIELD_PREP(ADXL313_RANGE_MSK,
> > +                                         ADXL313_RANGE_4G));
> > +     if (ret)
> > +             return ret;
> > +
> > +     /* Enables full resolution */
> > +     ret = regmap_update_bits(data->regmap, ADXL313_REG_DATA_FORMAT,
> > +                              ADXL313_FULL_RES, ADXL313_FULL_RES);
> > +     if (ret)
> > +             return ret;
> > +
> > +     /* Enables measurement mode */
> > +     return regmap_update_bits(data->regmap, ADXL313_REG_POWER_CTL,
> > +                               ADXL313_POWER_CTL_MSK,
> > +                               ADXL313_MEASUREMENT_MODE);
> > +}
> > +
> > +int adxl313_core_probe(struct device *dev, struct regmap *regmap,
> > +                    const char *name)
> > +{
> > +     struct adxl313_data *data;
> > +     struct iio_dev *indio_dev;
> > +     int ret;
> > +
> > +     indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
> > +     if (!indio_dev)
> > +             return -ENOMEM;
> > +
> > +     data = iio_priv(indio_dev);
> > +     data->regmap = regmap;
> > +     mutex_init(&data->lock);
> > +
> > +     indio_dev->name = name;
> > +     indio_dev->info = &adxl313_info;
> > +     indio_dev->modes = INDIO_DIRECT_MODE;
> > +     indio_dev->channels = adxl313_channels;
> > +     indio_dev->num_channels = ARRAY_SIZE(adxl313_channels);
> > +
> > +     ret = adxl313_setup(dev, data);
> > +     if (ret) {
> > +             dev_err(dev, "ADXL313 setup failed\n");
> > +             return ret;
> > +     }
> > +
> > +     return devm_iio_device_register(dev, indio_dev);
> > +}
> > +EXPORT_SYMBOL_GPL(adxl313_core_probe);
> > +
> > +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> > +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer core driver");
> > +MODULE_LICENSE("GPL v2");
> > diff --git a/drivers/iio/accel/adxl313_i2c.c b/drivers/iio/accel/adxl313_i2c.c
> > new file mode 100644
> > index 000000000000..65050a2fbd38
> > --- /dev/null
> > +++ b/drivers/iio/accel/adxl313_i2c.c
> > @@ -0,0 +1,65 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * ADXL313 3-Axis Digital Accelerometer
> > + *
> > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > + *
> > + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > + */
> > +
> > +#include <linux/i2c.h>
> > +#include <linux/module.h>
> > +#include <linux/regmap.h>
> > +
> > +#include "adxl313.h"
> > +
> > +static const struct regmap_config adxl313_i2c_regmap_config = {
> > +     .reg_bits       = 8,
> > +     .val_bits       = 8,
> > +     .rd_table       = &adxl313_readable_regs_table,
> > +     .wr_table       = &adxl313_writable_regs_table,
> > +     .max_register   = 0x39
> > +};
> > +
> > +static int adxl313_i2c_probe(struct i2c_client *client)
> > +{
> > +     struct regmap *regmap;
> > +
> > +     regmap = devm_regmap_init_i2c(client, &adxl313_i2c_regmap_config);
> > +     if (IS_ERR(regmap)) {
> > +             dev_err(&client->dev, "Error initializing i2c regmap: %ld\n",
> > +                     PTR_ERR(regmap));
> > +             return PTR_ERR(regmap);
> > +     }
> > +
> > +     return adxl313_core_probe(&client->dev, regmap, client->name);
> > +}
> > +
> > +static const struct i2c_device_id adxl313_i2c_id[] = {
> > +     { "adxl313", 0 },
>
> No real need to set the data value if it's just going to be 0.
>         { "adl313 },
> is fine.
>
> > +     { }
> > +};
> > +
> > +MODULE_DEVICE_TABLE(i2c, adxl313_i2c_id);
> > +
> > +static const struct of_device_id adxl313_of_match[] = {
> > +     { .compatible = "adi,adxl313" },
> > +     { },
> > +};
> > +
> > +MODULE_DEVICE_TABLE(of, adxl313_of_match);
> > +
> > +static struct i2c_driver adxl313_i2c_driver = {
> > +     .driver = {
> > +             .name   = "adxl313_i2c",
> > +             .of_match_table = adxl313_of_match,
> > +     },
> > +     .probe_new      = adxl313_i2c_probe,
> > +     .id_table       = adxl313_i2c_id,
> > +};
> > +
> > +module_i2c_driver(adxl313_i2c_driver);
> > +
> > +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> > +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer I2C driver");
> > +MODULE_LICENSE("GPL v2");
> > diff --git a/drivers/iio/accel/adxl313_spi.c b/drivers/iio/accel/adxl313_spi.c
> > new file mode 100644
> > index 000000000000..7c58c9ff8985
> > --- /dev/null
> > +++ b/drivers/iio/accel/adxl313_spi.c
> > @@ -0,0 +1,74 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * ADXL313 3-Axis Digital Accelerometer
> > + *
> > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > + *
> > + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > + */
> > +
> > +#include <linux/module.h>
> > +#include <linux/regmap.h>
> > +#include <linux/spi/spi.h>
> > +
> > +#include "adxl313.h"
> > +
> > +static const struct regmap_config adxl313_spi_regmap_config = {
> > +     .reg_bits       = 8,
> > +     .val_bits       = 8,
> > +     .rd_table       = &adxl313_readable_regs_table,
> > +     .wr_table       = &adxl313_writable_regs_table,
> > +     .max_register   = 0x39,
> > +      /* Setting bits 7 and 6 enables multiple-byte read */
> > +     .read_flag_mask = BIT(7) | BIT(6)
> > +};
> > +
> > +static int adxl313_spi_probe(struct spi_device *spi)
> > +{
> > +     const struct spi_device_id *id = spi_get_device_id(spi);
> > +     struct regmap *regmap;
> > +     int ret;
> > +
> > +     regmap = devm_regmap_init_spi(spi, &adxl313_spi_regmap_config);
> > +     if (IS_ERR(regmap)) {
> > +             dev_err(&spi->dev, "Error initializing spi regmap: %ld\n",
> > +                     PTR_ERR(regmap));
> > +             return PTR_ERR(regmap);
> > +     }
> > +
> > +     ret = adxl313_core_probe(&spi->dev, regmap, id->name);
> > +     if (ret < 0)
> > +             return ret;
> > +
> > +     return regmap_update_bits(regmap, ADXL313_REG_POWER_CTL,
> > +                               ADXL313_I2C_DISABLE, ADXL313_I2C_DISABLE);
>
> Why is this only done after the rest of probe?  Needs a comment perhaps.
> Normally I'd expect the core probe and hence exposure of the device
> to userspace etc to be the last thing done.
>

I'm doing this here for the same reason as for the spi-3wire setup. So
if I drop the reset in the probe, the bits could be updated before it.


> > +}
> > +
> > +static const struct spi_device_id adxl313_spi_id[] = {
> > +     { "adxl313", 0 },
> > +     { }
> > +};
> > +
> > +MODULE_DEVICE_TABLE(spi, adxl313_spi_id);
> > +
> > +static const struct of_device_id adxl313_of_match[] = {
> > +     { .compatible = "adi,adxl313" },
> > +     { },
> > +};
> > +
> > +MODULE_DEVICE_TABLE(of, adxl313_of_match);
> > +
> > +static struct spi_driver adxl313_spi_driver = {
> > +     .driver = {
> > +             .name   = "adxl313_spi",
> > +             .of_match_table = adxl313_of_match,
> > +     },
> > +     .probe          = adxl313_spi_probe,
> > +     .id_table       = adxl313_spi_id,
> > +};
> > +
> > +module_spi_driver(adxl313_spi_driver);
> > +
> > +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> > +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer SPI driver");
> > +MODULE_LICENSE("GPL v2");
>

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH 2/2] iio: accel: Add driver support for ADXL313
  2021-08-02  6:57     ` Alexandru Ardelean
@ 2021-08-02 17:28       ` Lucas Stankus
  2021-08-03  7:15         ` Alexandru Ardelean
  0 siblings, 1 reply; 14+ messages in thread
From: Lucas Stankus @ 2021-08-02 17:28 UTC (permalink / raw)
  To: Alexandru Ardelean
  Cc: Jonathan Cameron, Lars-Peter Clausen, Hennerich, Michael,
	Rob Herring, Bogdan, Dragos, Berghe, Darius, linux-iio,
	devicetree, LKML

On Mon, Aug 2, 2021 at 3:57 AM Alexandru Ardelean
<ardeleanalex@gmail.com> wrote:
>
> On Sun, Aug 1, 2021 at 9:09 PM Jonathan Cameron <jic23@kernel.org> wrote:
> >
> > On Sat, 31 Jul 2021 17:36:48 -0300
> > Lucas Stankus <lucas.p.stankus@gmail.com> wrote:
> >
> > > ADXL313 is a small, thin, low power, 3-axis accelerometer with high
> > > resolution measurement up to +/-4g. It includes an integrated 32-level
> > > FIFO and has activity and inactivity sensing capabilities.
> > >
> > > Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > >
> > > Signed-off-by: Lucas Stankus <lucas.p.stankus@gmail.com>
> >
> > Very nice.  A few really minor things inline.
> >
> > Jonathan
> >
> > > ---
> > >  MAINTAINERS                      |   9 +
> > >  drivers/iio/accel/Kconfig        |  29 +++
> > >  drivers/iio/accel/Makefile       |   3 +
> > >  drivers/iio/accel/adxl313.h      |  60 ++++++
> > >  drivers/iio/accel/adxl313_core.c | 323 +++++++++++++++++++++++++++++++
> > >  drivers/iio/accel/adxl313_i2c.c  |  65 +++++++
> > >  drivers/iio/accel/adxl313_spi.c  |  74 +++++++
> > >  7 files changed, 563 insertions(+)
> > >  create mode 100644 drivers/iio/accel/adxl313.h
> > >  create mode 100644 drivers/iio/accel/adxl313_core.c
> > >  create mode 100644 drivers/iio/accel/adxl313_i2c.c
> > >  create mode 100644 drivers/iio/accel/adxl313_spi.c
> > >
> > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > index a61f4f3b78a9..1fc88723e632 100644
> > > --- a/MAINTAINERS
> > > +++ b/MAINTAINERS
> > > @@ -585,6 +585,15 @@ L:       platform-driver-x86@vger.kernel.org
> > >  S:   Maintained
> > >  F:   drivers/platform/x86/adv_swbutton.c
> > >
> > > +ADXL313 THREE-AXIS DIGITAL ACCELEROMETER DRIVER
> > > +M:   Lucas Stankus <lucas.p.stankus@gmail.com>
> > > +S:   Supported
> > > +F:   Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
> > > +F:   drivers/iio/accel/adxl313.h
> > > +F:   drivers/iio/accel/adxl313_core.c
> > > +F:   drivers/iio/accel/adxl313_i2c.c
> > > +F:   drivers/iio/accel/adxl313_spi.c
> > > +
> > >  ADXL34X THREE-AXIS DIGITAL ACCELEROMETER DRIVER (ADXL345/ADXL346)
> > >  M:   Michael Hennerich <michael.hennerich@analog.com>
> > >  S:   Supported
> > > diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
> > > index 0e56ace61103..ae621532e716 100644
> > > --- a/drivers/iio/accel/Kconfig
> > > +++ b/drivers/iio/accel/Kconfig
> > > @@ -30,6 +30,35 @@ config ADIS16209
> > >         To compile this driver as a module, say M here: the module will be
> > >         called adis16209.
> > >
> > > +config ADXL313
> > > +     tristate
> > > +
> > > +config ADXL313_I2C
> > > +     tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer I2C Driver"
> > > +     depends on I2C
> > > +     select ADXL313
> > > +     select REGMAP_I2C
> > > +     help
> > > +       Say Y here if you want to build i2c support for the Analog Devices
> > > +       ADXL313 3-axis digital accelerometer.
> > > +
> > > +       To compile this driver as a module, choose M here: the module
> > > +       will be called adxl313_i2c and you will also get adxl313_core
> > > +       for the core module.
> > > +
> > > +config ADXL313_SPI
> > > +     tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer SPI Driver"
> > > +     depends on SPI
> > > +     select ADXL313
> > > +     select REGMAP_SPI
> > > +     help
> > > +       Say Y here if you want to build spi support for the Analog Devices
> > > +       ADXL313 3-axis digital accelerometer.
> > > +
> > > +       To compile this driver as a module, choose M here: the module
> > > +       will be called adxl313_spi and you will also get adxl313_core
> > > +       for the core module.
> > > +
> > >  config ADXL345
> > >       tristate
> > >
> > > diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
> > > index 89280e823bcd..fadc92816e24 100644
> > > --- a/drivers/iio/accel/Makefile
> > > +++ b/drivers/iio/accel/Makefile
> > > @@ -6,6 +6,9 @@
> > >  # When adding new entries keep the list in alphabetical order
> > >  obj-$(CONFIG_ADIS16201) += adis16201.o
> > >  obj-$(CONFIG_ADIS16209) += adis16209.o
> > > +obj-$(CONFIG_ADXL313) += adxl313_core.o
> > > +obj-$(CONFIG_ADXL313_I2C) += adxl313_i2c.o
> > > +obj-$(CONFIG_ADXL313_SPI) += adxl313_spi.o
> > >  obj-$(CONFIG_ADXL345) += adxl345_core.o
> > >  obj-$(CONFIG_ADXL345_I2C) += adxl345_i2c.o
> > >  obj-$(CONFIG_ADXL345_SPI) += adxl345_spi.o
> > > diff --git a/drivers/iio/accel/adxl313.h b/drivers/iio/accel/adxl313.h
> > > new file mode 100644
> > > index 000000000000..72f268e02a80
> > > --- /dev/null
> > > +++ b/drivers/iio/accel/adxl313.h
> > > @@ -0,0 +1,60 @@
> > > +/* SPDX-License-Identifier: GPL-2.0-only */
> > > +/*
> > > + * ADXL313 3-Axis Digital Accelerometer
> > > + *
> > > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > > + */
> > > +
> > > +#ifndef _ADXL313_H_
> > > +#define _ADXL313_H_
> > > +
> > > +/* ADXL313 register definitions */
> >
> > If these are only used in the c file, push them down there. Better to
> > keep what is in the header to absolute minimum.
> > however I suggest below moving some of this so that won't be true any more,
> > so maybe you do want to keep them here!
> >
> >
> > > +#define ADXL313_REG_DEVID0           0x00
> > > +#define ADXL313_REG_DEVID1           0x01
> > > +#define ADXL313_REG_PARTID           0x02
> > > +#define ADXL313_REG_XID                      0x04
> > > +#define ADXL313_REG_SOFT_RESET               0x18
> > > +#define ADXL313_REG_OFS_AXIS(index)  (0x1E + (index))
> > > +#define ADXL313_REG_THRESH_ACT               0x24
> > > +#define ADXL313_REG_ACT_INACT_CTL    0x27
> > > +#define ADXL313_REG_BW_RATE          0x2C
> > > +#define ADXL313_REG_POWER_CTL                0x2D
> > > +#define ADXL313_REG_INT_MAP          0x2F
> > > +#define ADXL313_REG_DATA_FORMAT              0x31
> > > +#define ADXL313_REG_DATAX            0x32
> > > +#define ADXL313_REG_DATAY            0x34
> > > +#define ADXL313_REG_DATAZ            0x36
> > > +#define ADXL313_REG_FIFO_CTL         0x38
> > > +#define ADXL313_REG_FIFO_STATUS              0x39
> > > +
> > > +#define ADXL313_DEVID0                       0xAD
> > > +#define ADXL313_DEVID1                       0x1D
> > > +#define ADXL313_PARTID                       0xCB
> > > +#define ADXL313_SOFT_RESET           0x52
> > > +
> > > +#define ADXL313_RATE_MSK             GENMASK(3, 0)
> > > +#define ADXL313_RATE_BASE            6
> > > +
> > > +#define ADXL313_POWER_CTL_MSK                GENMASK(3, 2)
> > > +#define ADXL313_MEASUREMENT_MODE     BIT(3)
> > > +
> > > +#define ADXL313_RANGE_MSK            GENMASK(1, 0)
> > > +#define ADXL313_RANGE_4G             3
> > > +
> > > +#define ADXL313_FULL_RES             BIT(3)
> > > +#define ADXL313_SPI_3WIRE            BIT(6)
> > > +#define ADXL313_I2C_DISABLE          BIT(6)
> > > +
> > > +/*
> > > + * Scale for any g range is given in datasheet as
> > > + * 1024 LSB/g = 0.0009765625 * 9.80665 = 0.009576806640625 m/s^2
> > > + */
> > > +#define ADXL313_NSCALE 9576806
> > > +
> > > +extern const struct regmap_access_table adxl313_readable_regs_table;
> > > +
> > > +extern const struct regmap_access_table adxl313_writable_regs_table;
> > > +
> > > +int adxl313_core_probe(struct device *dev, struct regmap *regmap,
> > > +                    const char *name);
> > > +#endif /* _ADXL313_H_ */
> > > diff --git a/drivers/iio/accel/adxl313_core.c b/drivers/iio/accel/adxl313_core.c
> > > new file mode 100644
> > > index 000000000000..76382ab4f0f4
> > > --- /dev/null
> > > +++ b/drivers/iio/accel/adxl313_core.c
> > > @@ -0,0 +1,323 @@
> > > +// SPDX-License-Identifier: GPL-2.0-only
> > > +/*
> > > + * ADXL313 3-Axis Digital Accelerometer
> > > + *
> > > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > > + *
> > > + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > > + */
> > > +
> > > +#include <linux/bitfield.h>
> > > +#include <linux/iio/iio.h>
> > > +#include <linux/module.h>
> > > +#include <linux/regmap.h>
> > > +
> > > +#include "adxl313.h"
> > > +
> > > +const struct regmap_range adxl313_readable_reg_range[] = {
> > > +     regmap_reg_range(ADXL313_REG_DEVID0, ADXL313_REG_XID),
> > > +     regmap_reg_range(ADXL313_REG_SOFT_RESET, ADXL313_REG_SOFT_RESET),
> > > +     regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
> > > +     regmap_reg_range(ADXL313_REG_THRESH_ACT, ADXL313_REG_ACT_INACT_CTL),
> > > +     regmap_reg_range(ADXL313_REG_BW_RATE, ADXL313_REG_FIFO_STATUS)
> > > +};
> > > +
> > > +const struct regmap_access_table adxl313_readable_regs_table = {
> > > +     .yes_ranges = adxl313_readable_reg_range,
> > > +     .n_yes_ranges = ARRAY_SIZE(adxl313_readable_reg_range)
> > > +};
> > > +EXPORT_SYMBOL_GPL(adxl313_readable_regs_table);
> > > +
> > > +const struct regmap_range adxl313_writable_reg_range[] = {
> > > +     regmap_reg_range(ADXL313_REG_SOFT_RESET, ADXL313_REG_SOFT_RESET),
> > > +     regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
> > > +     regmap_reg_range(ADXL313_REG_THRESH_ACT, ADXL313_REG_ACT_INACT_CTL),
> > > +     regmap_reg_range(ADXL313_REG_BW_RATE, ADXL313_REG_INT_MAP),
> > > +     regmap_reg_range(ADXL313_REG_DATA_FORMAT, ADXL313_REG_DATA_FORMAT),
> > > +     regmap_reg_range(ADXL313_REG_FIFO_CTL, ADXL313_REG_FIFO_CTL)
> > > +};
> > > +
> > > +const struct regmap_access_table adxl313_writable_regs_table = {
> > > +     .yes_ranges = adxl313_writable_reg_range,
> > > +     .n_yes_ranges = ARRAY_SIZE(adxl313_writable_reg_range)
> > > +};
> > > +EXPORT_SYMBOL_GPL(adxl313_writable_regs_table);
> > > +
> > > +struct adxl313_data {
> > > +     struct regmap   *regmap;
> > > +     struct mutex    lock; /* lock to protect transf_buf */
> > > +     __le16          transf_buf ____cacheline_aligned;
> > > +};
> > > +
> > > +static const int adxl313_odr_freqs[][2] = {
> > > +     [0] = { 6, 250000 },
> > > +     [1] = { 12, 500000 },
> > > +     [2] = { 25, 0 },
> > > +     [3] = { 50, 0 },
> > > +     [4] = { 100, 0 },
> > > +     [5] = { 200, 0 },
> > > +     [6] = { 400, 0 },
> > > +     [7] = { 800, 0 },
> > > +     [8] = { 1600, 0 },
> > > +     [9] = { 3200, 0 },
> > > +};
> > > +
> > > +#define ADXL313_ACCEL_CHANNEL(index, addr, axis) {                   \
> > > +     .type = IIO_ACCEL,                                              \
> > > +     .address = addr,                                                \
> > > +     .modified = 1,                                                  \
> > > +     .channel2 = IIO_MOD_##axis,                                     \
> > > +     .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |                  \
> > > +                           BIT(IIO_CHAN_INFO_CALIBBIAS),             \
> > > +     .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |          \
> > > +                                 BIT(IIO_CHAN_INFO_SAMP_FREQ),       \
> > > +     .info_mask_shared_by_type_available =                           \
> > > +             BIT(IIO_CHAN_INFO_SAMP_FREQ),                           \
> > > +     .scan_index = index,                                            \
> > > +     .scan_type = {                                                  \
> > > +             .sign = 's',                                            \
> > > +             .realbits = 13,                                         \
> > > +             .storagebits = 16,                                      \
> > > +             .endianness = IIO_LE,                                   \
> > > +     },                                                              \
> > > +}
> > > +
> > > +static const struct iio_chan_spec adxl313_channels[] = {
> > > +     ADXL313_ACCEL_CHANNEL(0, ADXL313_REG_DATAX, X),
> > > +     ADXL313_ACCEL_CHANNEL(1, ADXL313_REG_DATAY, Y),
> > > +     ADXL313_ACCEL_CHANNEL(2, ADXL313_REG_DATAZ, Z),
> > > +};
> > > +
> > > +static int adxl313_set_odr(struct adxl313_data *data,
> > > +                        unsigned int freq1, unsigned int freq2)
> > > +{
> > > +     unsigned int i;
> > > +
> > > +     for (i = 0; i < ARRAY_SIZE(adxl313_odr_freqs); i++) {
> > > +             if (adxl313_odr_freqs[i][0] == freq1 &&
> > > +                 adxl313_odr_freqs[i][1] == freq2)
> > > +                     break;
> > > +     }
> > > +
> > > +     if (i == ARRAY_SIZE(adxl313_odr_freqs))
> > > +             return -EINVAL;
> > > +
> > > +     return regmap_update_bits(data->regmap, ADXL313_REG_BW_RATE,
> > > +                               ADXL313_RATE_MSK,
> > > +                               FIELD_PREP(ADXL313_RATE_MSK,
> > > +                                          ADXL313_RATE_BASE + i));
> > > +}
> > > +
> > > +static int adxl313_read_axis(struct adxl313_data *data,
> > > +                          struct iio_chan_spec const *chan)
> > > +{
> > > +     int ret;
> > > +
> > > +     mutex_lock(&data->lock);
> > > +
> > > +     ret = regmap_bulk_read(data->regmap,
> > > +                            chan->address,
> > > +                            &data->transf_buf, 2);
> > > +     if (ret)
> > > +             goto unlock_ret;
> > > +
> > > +     ret = le16_to_cpu(data->transf_buf);
> > > +
> > > +unlock_ret:
> > > +     mutex_unlock(&data->lock);
> > > +     return ret;
> > > +}
> > > +
> > > +static int adxl313_read_freq_avail(struct iio_dev *indio_dev,
> > > +                                struct iio_chan_spec const *chan,
> > > +                                const int **vals, int *type, int *length,
> > > +                                long mask)
> > > +{
> > > +     switch (mask) {
> > > +     case IIO_CHAN_INFO_SAMP_FREQ:
> > > +             *vals = (const int *)adxl313_odr_freqs;
> > > +             *length = ARRAY_SIZE(adxl313_odr_freqs) * 2;
> > > +             *type = IIO_VAL_INT_PLUS_MICRO;
> > > +             return IIO_AVAIL_LIST;
> > > +     }
> > > +
> > > +     return -EINVAL;
> > > +}
> > > +
> > > +static int adxl313_read_raw(struct iio_dev *indio_dev,
> > > +                         struct iio_chan_spec const *chan,
> > > +                         int *val, int *val2, long mask)
> > > +{
> > > +     struct adxl313_data *data = iio_priv(indio_dev);
> > > +     unsigned int regval;
> > > +     int ret;
> > > +
> > > +     switch (mask) {
> > > +     case IIO_CHAN_INFO_RAW:
> > > +             ret = adxl313_read_axis(data, chan);
> > > +             if (ret < 0)
> > > +                     return ret;
> > > +
> > > +             *val = sign_extend32(ret, chan->scan_type.realbits - 1);
> > > +             return IIO_VAL_INT;
> > > +     case IIO_CHAN_INFO_SCALE:
> > > +             *val = 0;
> > > +             *val2 = ADXL313_NSCALE;
> > > +             return IIO_VAL_INT_PLUS_NANO;
> > > +     case IIO_CHAN_INFO_CALIBBIAS:
> > > +             ret = regmap_read(data->regmap,
> > > +                               ADXL313_REG_OFS_AXIS(chan->scan_index),
> > > +                               &regval);
> > > +             if (ret)
> > > +                     return ret;
> > > +
> > > +             /*
> > > +              * 8-bit resolution at +/- 0.5g, that is 4x accel data scale
> > > +              * factor at full resolution
> > > +              */
> > > +             *val = sign_extend32(regval, 7) * 4;
> > > +             return IIO_VAL_INT;
> > > +     case IIO_CHAN_INFO_SAMP_FREQ:
> > > +             ret = regmap_read(data->regmap, ADXL313_REG_BW_RATE, &regval);
> > > +             if (ret)
> > > +                     return ret;
> > > +
> > > +             ret = FIELD_GET(ADXL313_RATE_MSK, regval) - ADXL313_RATE_BASE;
> > > +             *val = adxl313_odr_freqs[ret][0];
> > > +             *val2 = adxl313_odr_freqs[ret][1];
> > > +             return IIO_VAL_INT_PLUS_MICRO;
> > > +     }
> > > +
> > > +     return -EINVAL;
> > > +}
> > > +
> > > +static int adxl313_write_raw(struct iio_dev *indio_dev,
> > > +                          struct iio_chan_spec const *chan,
> > > +                          int val, int val2, long mask)
> > > +{
> > > +     struct adxl313_data *data = iio_priv(indio_dev);
> > > +
> > > +     switch (mask) {
> > > +     case IIO_CHAN_INFO_CALIBBIAS:
> > > +             /*
> > > +              * 8-bit resolution at +/- 0.5g, that is 4x accel data scale
> > > +              * factor at full resolution
> > > +              */
> > > +             if (val > 127 * 4 || val < -128 * 4)
> > > +                     return -EINVAL;
> > > +
> > > +             return regmap_write(data->regmap,
> > > +                                 ADXL313_REG_OFS_AXIS(chan->scan_index),
> > > +                                 val / 4);
> > > +     case IIO_CHAN_INFO_SAMP_FREQ:
> > > +             return adxl313_set_odr(data, val, val2);
> > > +     }
> > > +
> > > +     return -EINVAL;
> >
> > Put this as a default in the case otherwise you might get warnings saying you
> > don't handle all the possible values.
> >
> > > +}
> > > +
> > > +static const struct iio_info adxl313_info = {
> > > +     .read_raw       = adxl313_read_raw,
> > > +     .write_raw      = adxl313_write_raw,
> > > +     .read_avail     = adxl313_read_freq_avail
> > > +};
> > > +
> > > +static int adxl313_setup(struct device *dev, struct adxl313_data *data)
> > > +{
> > > +     unsigned int regval;
> > > +     int ret;
> > > +
> > > +     /* Ensures the device is in a consistent state after start up */
> > > +     ret = regmap_write(data->regmap, ADXL313_REG_SOFT_RESET,
> > > +                        ADXL313_SOFT_RESET);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     if (device_property_read_bool(dev, "spi-3wire")) {
> >
> > Rather odd to see spi specific stuff in here.  Perhaps provide a callback to
> > common probe if it needs to be done at this point in bringing the device up.
> > However, I think you can just do this before calling the common_probe()
>
> This is a recurring theme in some ADI chips, where the chip supports
> both 3wire and 4wire SPI modes.
>
> But this has some tendency to create confusion and a bit duplication.
> Because "spi-3wire" is also valid in `drivers/spi/spi.c` in the SPI framework.
> So, it gets parsed [only for OF] by the SPI framework [hence the duplication].
> But, then,if the SPI controller doesn't support 3wire mode, this
> setting gets invalidated inside the SPI framework; the chip remains in
> 3wire mode anyway.
>
> [if the above happens] This setting can work if there is a passive
> SPI-mode converter [from 4wire to 3wire]
> Which is not a great way to describe the HW, but it's the best we can
> do for now.
>

Thanks for the insight.

Would it be better to drop 3wire support then? I believe that there
isn't much of a loss in not supporting 3wire when 4wire is already
working, so I think that writing a converter wouldn't be worth the
effort in this case.

> This comes back to an older discussion about overriding spi-cpol &
> spi-cpha in the DT in case there are some weird board designs.
> The driver would specify some mode, but the DT could override it, in
> case it is needed.
> I had a plan to do a general approach for this, but did not get to it.
>
> >
> > > +             ret = regmap_write(data->regmap, ADXL313_REG_DATA_FORMAT,
> > > +                                ADXL313_SPI_3WIRE);
> > > +             if (ret)
> > > +                     return ret;
> > > +     }
> > > +
> > > +     ret = regmap_read(data->regmap, ADXL313_REG_DEVID0, &regval);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     if (regval != ADXL313_DEVID0) {
> > > +             dev_err(dev, "Invalid manufacturer ID: 0x%02x\n", regval);
> > > +             return -ENODEV;
> > > +     }
> > > +
> > > +     ret = regmap_read(data->regmap, ADXL313_REG_DEVID1, &regval);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     if (regval != ADXL313_DEVID1) {
> > > +             dev_err(dev, "Invalid mems ID: 0x%02x\n", regval);
> > > +             return -ENODEV;
> > > +     }
> > > +
> > > +     ret = regmap_read(data->regmap, ADXL313_REG_PARTID, &regval);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     if (regval != ADXL313_PARTID) {
> > > +             dev_err(dev, "Invalid device ID: 0x%02x\n", regval);
> > > +             return -ENODEV;
> > > +     }
> > > +
> > > +     /* Sets the range to +/- 4g */
> > > +     ret = regmap_update_bits(data->regmap, ADXL313_REG_DATA_FORMAT,
> > > +                              ADXL313_RANGE_MSK,
> > > +                              FIELD_PREP(ADXL313_RANGE_MSK,
> > > +                                         ADXL313_RANGE_4G));
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     /* Enables full resolution */
> > > +     ret = regmap_update_bits(data->regmap, ADXL313_REG_DATA_FORMAT,
> > > +                              ADXL313_FULL_RES, ADXL313_FULL_RES);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     /* Enables measurement mode */
> > > +     return regmap_update_bits(data->regmap, ADXL313_REG_POWER_CTL,
> > > +                               ADXL313_POWER_CTL_MSK,
> > > +                               ADXL313_MEASUREMENT_MODE);
> > > +}
> > > +
> > > +int adxl313_core_probe(struct device *dev, struct regmap *regmap,
> > > +                    const char *name)
> > > +{
> > > +     struct adxl313_data *data;
> > > +     struct iio_dev *indio_dev;
> > > +     int ret;
> > > +
> > > +     indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
> > > +     if (!indio_dev)
> > > +             return -ENOMEM;
> > > +
> > > +     data = iio_priv(indio_dev);
> > > +     data->regmap = regmap;
> > > +     mutex_init(&data->lock);
> > > +
> > > +     indio_dev->name = name;
> > > +     indio_dev->info = &adxl313_info;
> > > +     indio_dev->modes = INDIO_DIRECT_MODE;
> > > +     indio_dev->channels = adxl313_channels;
> > > +     indio_dev->num_channels = ARRAY_SIZE(adxl313_channels);
> > > +
> > > +     ret = adxl313_setup(dev, data);
> > > +     if (ret) {
> > > +             dev_err(dev, "ADXL313 setup failed\n");
> > > +             return ret;
> > > +     }
> > > +
> > > +     return devm_iio_device_register(dev, indio_dev);
> > > +}
> > > +EXPORT_SYMBOL_GPL(adxl313_core_probe);
> > > +
> > > +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> > > +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer core driver");
> > > +MODULE_LICENSE("GPL v2");
> > > diff --git a/drivers/iio/accel/adxl313_i2c.c b/drivers/iio/accel/adxl313_i2c.c
> > > new file mode 100644
> > > index 000000000000..65050a2fbd38
> > > --- /dev/null
> > > +++ b/drivers/iio/accel/adxl313_i2c.c
> > > @@ -0,0 +1,65 @@
> > > +// SPDX-License-Identifier: GPL-2.0-only
> > > +/*
> > > + * ADXL313 3-Axis Digital Accelerometer
> > > + *
> > > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > > + *
> > > + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > > + */
> > > +
> > > +#include <linux/i2c.h>
> > > +#include <linux/module.h>
> > > +#include <linux/regmap.h>
> > > +
> > > +#include "adxl313.h"
> > > +
> > > +static const struct regmap_config adxl313_i2c_regmap_config = {
> > > +     .reg_bits       = 8,
> > > +     .val_bits       = 8,
> > > +     .rd_table       = &adxl313_readable_regs_table,
> > > +     .wr_table       = &adxl313_writable_regs_table,
> > > +     .max_register   = 0x39
> > > +};
> > > +
> > > +static int adxl313_i2c_probe(struct i2c_client *client)
> > > +{
> > > +     struct regmap *regmap;
> > > +
> > > +     regmap = devm_regmap_init_i2c(client, &adxl313_i2c_regmap_config);
> > > +     if (IS_ERR(regmap)) {
> > > +             dev_err(&client->dev, "Error initializing i2c regmap: %ld\n",
> > > +                     PTR_ERR(regmap));
> > > +             return PTR_ERR(regmap);
> > > +     }
> > > +
> > > +     return adxl313_core_probe(&client->dev, regmap, client->name);
> > > +}
> > > +
> > > +static const struct i2c_device_id adxl313_i2c_id[] = {
> > > +     { "adxl313", 0 },
> >
> > No real need to set the data value if it's just going to be 0.
> >         { "adl313 },
> > is fine.
> >
> > > +     { }
> > > +};
> > > +
> > > +MODULE_DEVICE_TABLE(i2c, adxl313_i2c_id);
> > > +
> > > +static const struct of_device_id adxl313_of_match[] = {
> > > +     { .compatible = "adi,adxl313" },
> > > +     { },
> > > +};
> > > +
> > > +MODULE_DEVICE_TABLE(of, adxl313_of_match);
> > > +
> > > +static struct i2c_driver adxl313_i2c_driver = {
> > > +     .driver = {
> > > +             .name   = "adxl313_i2c",
> > > +             .of_match_table = adxl313_of_match,
> > > +     },
> > > +     .probe_new      = adxl313_i2c_probe,
> > > +     .id_table       = adxl313_i2c_id,
> > > +};
> > > +
> > > +module_i2c_driver(adxl313_i2c_driver);
> > > +
> > > +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> > > +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer I2C driver");
> > > +MODULE_LICENSE("GPL v2");
> > > diff --git a/drivers/iio/accel/adxl313_spi.c b/drivers/iio/accel/adxl313_spi.c
> > > new file mode 100644
> > > index 000000000000..7c58c9ff8985
> > > --- /dev/null
> > > +++ b/drivers/iio/accel/adxl313_spi.c
> > > @@ -0,0 +1,74 @@
> > > +// SPDX-License-Identifier: GPL-2.0-only
> > > +/*
> > > + * ADXL313 3-Axis Digital Accelerometer
> > > + *
> > > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > > + *
> > > + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > > + */
> > > +
> > > +#include <linux/module.h>
> > > +#include <linux/regmap.h>
> > > +#include <linux/spi/spi.h>
> > > +
> > > +#include "adxl313.h"
> > > +
> > > +static const struct regmap_config adxl313_spi_regmap_config = {
> > > +     .reg_bits       = 8,
> > > +     .val_bits       = 8,
> > > +     .rd_table       = &adxl313_readable_regs_table,
> > > +     .wr_table       = &adxl313_writable_regs_table,
> > > +     .max_register   = 0x39,
> > > +      /* Setting bits 7 and 6 enables multiple-byte read */
> > > +     .read_flag_mask = BIT(7) | BIT(6)
> > > +};
> > > +
> > > +static int adxl313_spi_probe(struct spi_device *spi)
> > > +{
> > > +     const struct spi_device_id *id = spi_get_device_id(spi);
> > > +     struct regmap *regmap;
> > > +     int ret;
> > > +
> > > +     regmap = devm_regmap_init_spi(spi, &adxl313_spi_regmap_config);
> > > +     if (IS_ERR(regmap)) {
> > > +             dev_err(&spi->dev, "Error initializing spi regmap: %ld\n",
> > > +                     PTR_ERR(regmap));
> > > +             return PTR_ERR(regmap);
> > > +     }
> > > +
> > > +     ret = adxl313_core_probe(&spi->dev, regmap, id->name);
> > > +     if (ret < 0)
> > > +             return ret;
> > > +
> > > +     return regmap_update_bits(regmap, ADXL313_REG_POWER_CTL,
> > > +                               ADXL313_I2C_DISABLE, ADXL313_I2C_DISABLE);
> >
> > Why is this only done after the rest of probe?  Needs a comment perhaps.
> > Normally I'd expect the core probe and hence exposure of the device
> > to userspace etc to be the last thing done.
> >
> > > +}
> > > +
> > > +static const struct spi_device_id adxl313_spi_id[] = {
> > > +     { "adxl313", 0 },
> > > +     { }
> > > +};
> > > +
> > > +MODULE_DEVICE_TABLE(spi, adxl313_spi_id);
> > > +
> > > +static const struct of_device_id adxl313_of_match[] = {
> > > +     { .compatible = "adi,adxl313" },
> > > +     { },
> > > +};
> > > +
> > > +MODULE_DEVICE_TABLE(of, adxl313_of_match);
> > > +
> > > +static struct spi_driver adxl313_spi_driver = {
> > > +     .driver = {
> > > +             .name   = "adxl313_spi",
> > > +             .of_match_table = adxl313_of_match,
> > > +     },
> > > +     .probe          = adxl313_spi_probe,
> > > +     .id_table       = adxl313_spi_id,
> > > +};
> > > +
> > > +module_spi_driver(adxl313_spi_driver);
> > > +
> > > +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> > > +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer SPI driver");
> > > +MODULE_LICENSE("GPL v2");
> >

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH 2/2] iio: accel: Add driver support for ADXL313
  2021-08-02  7:04   ` Alexandru Ardelean
@ 2021-08-02 17:30     ` Lucas Stankus
  0 siblings, 0 replies; 14+ messages in thread
From: Lucas Stankus @ 2021-08-02 17:30 UTC (permalink / raw)
  To: Alexandru Ardelean
  Cc: Lars-Peter Clausen, Hennerich, Michael, Jonathan Cameron,
	Rob Herring, Bogdan, Dragos, Berghe, Darius, linux-iio,
	devicetree, LKML

On Mon, Aug 2, 2021 at 4:04 AM Alexandru Ardelean
<ardeleanalex@gmail.com> wrote:
>
> On Sat, Jul 31, 2021 at 11:37 PM Lucas Stankus
> <lucas.p.stankus@gmail.com> wrote:
> >
> > ADXL313 is a small, thin, low power, 3-axis accelerometer with high
> > resolution measurement up to +/-4g. It includes an integrated 32-level
> > FIFO and has activity and inactivity sensing capabilities.
> >
>
> I have just one small note to add on top of what Jonathan said, about
> the null terminator.
> Since this may be getting a V2, I thought it could go in.
>
> > Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> >
> > Signed-off-by: Lucas Stankus <lucas.p.stankus@gmail.com>
> > ---
> >  MAINTAINERS                      |   9 +
> >  drivers/iio/accel/Kconfig        |  29 +++
> >  drivers/iio/accel/Makefile       |   3 +
> >  drivers/iio/accel/adxl313.h      |  60 ++++++
> >  drivers/iio/accel/adxl313_core.c | 323 +++++++++++++++++++++++++++++++
> >  drivers/iio/accel/adxl313_i2c.c  |  65 +++++++
> >  drivers/iio/accel/adxl313_spi.c  |  74 +++++++
> >  7 files changed, 563 insertions(+)
> >  create mode 100644 drivers/iio/accel/adxl313.h
> >  create mode 100644 drivers/iio/accel/adxl313_core.c
> >  create mode 100644 drivers/iio/accel/adxl313_i2c.c
> >  create mode 100644 drivers/iio/accel/adxl313_spi.c
> >
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index a61f4f3b78a9..1fc88723e632 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -585,6 +585,15 @@ L: platform-driver-x86@vger.kernel.org
> >  S:     Maintained
> >  F:     drivers/platform/x86/adv_swbutton.c
> >
> > +ADXL313 THREE-AXIS DIGITAL ACCELEROMETER DRIVER
> > +M:     Lucas Stankus <lucas.p.stankus@gmail.com>
> > +S:     Supported
> > +F:     Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
> > +F:     drivers/iio/accel/adxl313.h
> > +F:     drivers/iio/accel/adxl313_core.c
> > +F:     drivers/iio/accel/adxl313_i2c.c
> > +F:     drivers/iio/accel/adxl313_spi.c
> > +
> >  ADXL34X THREE-AXIS DIGITAL ACCELEROMETER DRIVER (ADXL345/ADXL346)
> >  M:     Michael Hennerich <michael.hennerich@analog.com>
> >  S:     Supported
> > diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
> > index 0e56ace61103..ae621532e716 100644
> > --- a/drivers/iio/accel/Kconfig
> > +++ b/drivers/iio/accel/Kconfig
> > @@ -30,6 +30,35 @@ config ADIS16209
> >           To compile this driver as a module, say M here: the module will be
> >           called adis16209.
> >
> > +config ADXL313
> > +       tristate
> > +
> > +config ADXL313_I2C
> > +       tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer I2C Driver"
> > +       depends on I2C
> > +       select ADXL313
> > +       select REGMAP_I2C
> > +       help
> > +         Say Y here if you want to build i2c support for the Analog Devices
> > +         ADXL313 3-axis digital accelerometer.
> > +
> > +         To compile this driver as a module, choose M here: the module
> > +         will be called adxl313_i2c and you will also get adxl313_core
> > +         for the core module.
> > +
> > +config ADXL313_SPI
> > +       tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer SPI Driver"
> > +       depends on SPI
> > +       select ADXL313
> > +       select REGMAP_SPI
> > +       help
> > +         Say Y here if you want to build spi support for the Analog Devices
> > +         ADXL313 3-axis digital accelerometer.
> > +
> > +         To compile this driver as a module, choose M here: the module
> > +         will be called adxl313_spi and you will also get adxl313_core
> > +         for the core module.
> > +
> >  config ADXL345
> >         tristate
> >
> > diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
> > index 89280e823bcd..fadc92816e24 100644
> > --- a/drivers/iio/accel/Makefile
> > +++ b/drivers/iio/accel/Makefile
> > @@ -6,6 +6,9 @@
> >  # When adding new entries keep the list in alphabetical order
> >  obj-$(CONFIG_ADIS16201) += adis16201.o
> >  obj-$(CONFIG_ADIS16209) += adis16209.o
> > +obj-$(CONFIG_ADXL313) += adxl313_core.o
> > +obj-$(CONFIG_ADXL313_I2C) += adxl313_i2c.o
> > +obj-$(CONFIG_ADXL313_SPI) += adxl313_spi.o
> >  obj-$(CONFIG_ADXL345) += adxl345_core.o
> >  obj-$(CONFIG_ADXL345_I2C) += adxl345_i2c.o
> >  obj-$(CONFIG_ADXL345_SPI) += adxl345_spi.o
> > diff --git a/drivers/iio/accel/adxl313.h b/drivers/iio/accel/adxl313.h
> > new file mode 100644
> > index 000000000000..72f268e02a80
> > --- /dev/null
> > +++ b/drivers/iio/accel/adxl313.h
> > @@ -0,0 +1,60 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +/*
> > + * ADXL313 3-Axis Digital Accelerometer
> > + *
> > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > + */
> > +
> > +#ifndef _ADXL313_H_
> > +#define _ADXL313_H_
> > +
> > +/* ADXL313 register definitions */
> > +#define ADXL313_REG_DEVID0             0x00
> > +#define ADXL313_REG_DEVID1             0x01
> > +#define ADXL313_REG_PARTID             0x02
> > +#define ADXL313_REG_XID                        0x04
> > +#define ADXL313_REG_SOFT_RESET         0x18
> > +#define ADXL313_REG_OFS_AXIS(index)    (0x1E + (index))
> > +#define ADXL313_REG_THRESH_ACT         0x24
> > +#define ADXL313_REG_ACT_INACT_CTL      0x27
> > +#define ADXL313_REG_BW_RATE            0x2C
> > +#define ADXL313_REG_POWER_CTL          0x2D
> > +#define ADXL313_REG_INT_MAP            0x2F
> > +#define ADXL313_REG_DATA_FORMAT                0x31
> > +#define ADXL313_REG_DATAX              0x32
> > +#define ADXL313_REG_DATAY              0x34
> > +#define ADXL313_REG_DATAZ              0x36
> > +#define ADXL313_REG_FIFO_CTL           0x38
> > +#define ADXL313_REG_FIFO_STATUS                0x39
> > +
> > +#define ADXL313_DEVID0                 0xAD
> > +#define ADXL313_DEVID1                 0x1D
> > +#define ADXL313_PARTID                 0xCB
> > +#define ADXL313_SOFT_RESET             0x52
> > +
> > +#define ADXL313_RATE_MSK               GENMASK(3, 0)
> > +#define ADXL313_RATE_BASE              6
> > +
> > +#define ADXL313_POWER_CTL_MSK          GENMASK(3, 2)
> > +#define ADXL313_MEASUREMENT_MODE       BIT(3)
> > +
> > +#define ADXL313_RANGE_MSK              GENMASK(1, 0)
> > +#define ADXL313_RANGE_4G               3
> > +
> > +#define ADXL313_FULL_RES               BIT(3)
> > +#define ADXL313_SPI_3WIRE              BIT(6)
> > +#define ADXL313_I2C_DISABLE            BIT(6)
> > +
> > +/*
> > + * Scale for any g range is given in datasheet as
> > + * 1024 LSB/g = 0.0009765625 * 9.80665 = 0.009576806640625 m/s^2
> > + */
> > +#define ADXL313_NSCALE 9576806
> > +
> > +extern const struct regmap_access_table adxl313_readable_regs_table;
> > +
> > +extern const struct regmap_access_table adxl313_writable_regs_table;
> > +
> > +int adxl313_core_probe(struct device *dev, struct regmap *regmap,
> > +                      const char *name);
> > +#endif /* _ADXL313_H_ */
> > diff --git a/drivers/iio/accel/adxl313_core.c b/drivers/iio/accel/adxl313_core.c
> > new file mode 100644
> > index 000000000000..76382ab4f0f4
> > --- /dev/null
> > +++ b/drivers/iio/accel/adxl313_core.c
> > @@ -0,0 +1,323 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * ADXL313 3-Axis Digital Accelerometer
> > + *
> > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > + *
> > + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > + */
> > +
> > +#include <linux/bitfield.h>
> > +#include <linux/iio/iio.h>
> > +#include <linux/module.h>
> > +#include <linux/regmap.h>
> > +
> > +#include "adxl313.h"
> > +
> > +const struct regmap_range adxl313_readable_reg_range[] = {
> > +       regmap_reg_range(ADXL313_REG_DEVID0, ADXL313_REG_XID),
> > +       regmap_reg_range(ADXL313_REG_SOFT_RESET, ADXL313_REG_SOFT_RESET),
> > +       regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
> > +       regmap_reg_range(ADXL313_REG_THRESH_ACT, ADXL313_REG_ACT_INACT_CTL),
> > +       regmap_reg_range(ADXL313_REG_BW_RATE, ADXL313_REG_FIFO_STATUS)
> > +};
> > +
> > +const struct regmap_access_table adxl313_readable_regs_table = {
> > +       .yes_ranges = adxl313_readable_reg_range,
> > +       .n_yes_ranges = ARRAY_SIZE(adxl313_readable_reg_range)
> > +};
> > +EXPORT_SYMBOL_GPL(adxl313_readable_regs_table);
> > +
> > +const struct regmap_range adxl313_writable_reg_range[] = {
> > +       regmap_reg_range(ADXL313_REG_SOFT_RESET, ADXL313_REG_SOFT_RESET),
> > +       regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
> > +       regmap_reg_range(ADXL313_REG_THRESH_ACT, ADXL313_REG_ACT_INACT_CTL),
> > +       regmap_reg_range(ADXL313_REG_BW_RATE, ADXL313_REG_INT_MAP),
> > +       regmap_reg_range(ADXL313_REG_DATA_FORMAT, ADXL313_REG_DATA_FORMAT),
> > +       regmap_reg_range(ADXL313_REG_FIFO_CTL, ADXL313_REG_FIFO_CTL)
> > +};
> > +
> > +const struct regmap_access_table adxl313_writable_regs_table = {
> > +       .yes_ranges = adxl313_writable_reg_range,
> > +       .n_yes_ranges = ARRAY_SIZE(adxl313_writable_reg_range)
> > +};
> > +EXPORT_SYMBOL_GPL(adxl313_writable_regs_table);
> > +
> > +struct adxl313_data {
> > +       struct regmap   *regmap;
> > +       struct mutex    lock; /* lock to protect transf_buf */
> > +       __le16          transf_buf ____cacheline_aligned;
> > +};
> > +
> > +static const int adxl313_odr_freqs[][2] = {
> > +       [0] = { 6, 250000 },
> > +       [1] = { 12, 500000 },
> > +       [2] = { 25, 0 },
> > +       [3] = { 50, 0 },
> > +       [4] = { 100, 0 },
> > +       [5] = { 200, 0 },
> > +       [6] = { 400, 0 },
> > +       [7] = { 800, 0 },
> > +       [8] = { 1600, 0 },
> > +       [9] = { 3200, 0 },
> > +};
> > +
> > +#define ADXL313_ACCEL_CHANNEL(index, addr, axis) {                     \
> > +       .type = IIO_ACCEL,                                              \
> > +       .address = addr,                                                \
> > +       .modified = 1,                                                  \
> > +       .channel2 = IIO_MOD_##axis,                                     \
> > +       .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |                  \
> > +                             BIT(IIO_CHAN_INFO_CALIBBIAS),             \
> > +       .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |          \
> > +                                   BIT(IIO_CHAN_INFO_SAMP_FREQ),       \
> > +       .info_mask_shared_by_type_available =                           \
> > +               BIT(IIO_CHAN_INFO_SAMP_FREQ),                           \
> > +       .scan_index = index,                                            \
> > +       .scan_type = {                                                  \
> > +               .sign = 's',                                            \
> > +               .realbits = 13,                                         \
> > +               .storagebits = 16,                                      \
> > +               .endianness = IIO_LE,                                   \
> > +       },                                                              \
> > +}
> > +
> > +static const struct iio_chan_spec adxl313_channels[] = {
> > +       ADXL313_ACCEL_CHANNEL(0, ADXL313_REG_DATAX, X),
> > +       ADXL313_ACCEL_CHANNEL(1, ADXL313_REG_DATAY, Y),
> > +       ADXL313_ACCEL_CHANNEL(2, ADXL313_REG_DATAZ, Z),
> > +};
> > +
> > +static int adxl313_set_odr(struct adxl313_data *data,
> > +                          unsigned int freq1, unsigned int freq2)
> > +{
> > +       unsigned int i;
> > +
> > +       for (i = 0; i < ARRAY_SIZE(adxl313_odr_freqs); i++) {
> > +               if (adxl313_odr_freqs[i][0] == freq1 &&
> > +                   adxl313_odr_freqs[i][1] == freq2)
> > +                       break;
> > +       }
> > +
> > +       if (i == ARRAY_SIZE(adxl313_odr_freqs))
> > +               return -EINVAL;
> > +
> > +       return regmap_update_bits(data->regmap, ADXL313_REG_BW_RATE,
> > +                                 ADXL313_RATE_MSK,
> > +                                 FIELD_PREP(ADXL313_RATE_MSK,
> > +                                            ADXL313_RATE_BASE + i));
> > +}
> > +
> > +static int adxl313_read_axis(struct adxl313_data *data,
> > +                            struct iio_chan_spec const *chan)
> > +{
> > +       int ret;
> > +
> > +       mutex_lock(&data->lock);
> > +
> > +       ret = regmap_bulk_read(data->regmap,
> > +                              chan->address,
> > +                              &data->transf_buf, 2);
> > +       if (ret)
> > +               goto unlock_ret;
> > +
> > +       ret = le16_to_cpu(data->transf_buf);
> > +
> > +unlock_ret:
> > +       mutex_unlock(&data->lock);
> > +       return ret;
> > +}
> > +
> > +static int adxl313_read_freq_avail(struct iio_dev *indio_dev,
> > +                                  struct iio_chan_spec const *chan,
> > +                                  const int **vals, int *type, int *length,
> > +                                  long mask)
> > +{
> > +       switch (mask) {
> > +       case IIO_CHAN_INFO_SAMP_FREQ:
> > +               *vals = (const int *)adxl313_odr_freqs;
> > +               *length = ARRAY_SIZE(adxl313_odr_freqs) * 2;
> > +               *type = IIO_VAL_INT_PLUS_MICRO;
> > +               return IIO_AVAIL_LIST;
> > +       }
> > +
> > +       return -EINVAL;
> > +}
> > +
> > +static int adxl313_read_raw(struct iio_dev *indio_dev,
> > +                           struct iio_chan_spec const *chan,
> > +                           int *val, int *val2, long mask)
> > +{
> > +       struct adxl313_data *data = iio_priv(indio_dev);
> > +       unsigned int regval;
> > +       int ret;
> > +
> > +       switch (mask) {
> > +       case IIO_CHAN_INFO_RAW:
> > +               ret = adxl313_read_axis(data, chan);
> > +               if (ret < 0)
> > +                       return ret;
> > +
> > +               *val = sign_extend32(ret, chan->scan_type.realbits - 1);
> > +               return IIO_VAL_INT;
> > +       case IIO_CHAN_INFO_SCALE:
> > +               *val = 0;
> > +               *val2 = ADXL313_NSCALE;
> > +               return IIO_VAL_INT_PLUS_NANO;
> > +       case IIO_CHAN_INFO_CALIBBIAS:
> > +               ret = regmap_read(data->regmap,
> > +                                 ADXL313_REG_OFS_AXIS(chan->scan_index),
> > +                                 &regval);
> > +               if (ret)
> > +                       return ret;
> > +
> > +               /*
> > +                * 8-bit resolution at +/- 0.5g, that is 4x accel data scale
> > +                * factor at full resolution
> > +                */
> > +               *val = sign_extend32(regval, 7) * 4;
> > +               return IIO_VAL_INT;
> > +       case IIO_CHAN_INFO_SAMP_FREQ:
> > +               ret = regmap_read(data->regmap, ADXL313_REG_BW_RATE, &regval);
> > +               if (ret)
> > +                       return ret;
> > +
> > +               ret = FIELD_GET(ADXL313_RATE_MSK, regval) - ADXL313_RATE_BASE;
> > +               *val = adxl313_odr_freqs[ret][0];
> > +               *val2 = adxl313_odr_freqs[ret][1];
> > +               return IIO_VAL_INT_PLUS_MICRO;
> > +       }
> > +
> > +       return -EINVAL;
> > +}
> > +
> > +static int adxl313_write_raw(struct iio_dev *indio_dev,
> > +                            struct iio_chan_spec const *chan,
> > +                            int val, int val2, long mask)
> > +{
> > +       struct adxl313_data *data = iio_priv(indio_dev);
> > +
> > +       switch (mask) {
> > +       case IIO_CHAN_INFO_CALIBBIAS:
> > +               /*
> > +                * 8-bit resolution at +/- 0.5g, that is 4x accel data scale
> > +                * factor at full resolution
> > +                */
> > +               if (val > 127 * 4 || val < -128 * 4)
> > +                       return -EINVAL;
> > +
> > +               return regmap_write(data->regmap,
> > +                                   ADXL313_REG_OFS_AXIS(chan->scan_index),
> > +                                   val / 4);
> > +       case IIO_CHAN_INFO_SAMP_FREQ:
> > +               return adxl313_set_odr(data, val, val2);
> > +       }
> > +
> > +       return -EINVAL;
> > +}
> > +
> > +static const struct iio_info adxl313_info = {
> > +       .read_raw       = adxl313_read_raw,
> > +       .write_raw      = adxl313_write_raw,
> > +       .read_avail     = adxl313_read_freq_avail
> > +};
> > +
> > +static int adxl313_setup(struct device *dev, struct adxl313_data *data)
> > +{
> > +       unsigned int regval;
> > +       int ret;
> > +
> > +       /* Ensures the device is in a consistent state after start up */
> > +       ret = regmap_write(data->regmap, ADXL313_REG_SOFT_RESET,
> > +                          ADXL313_SOFT_RESET);
> > +       if (ret)
> > +               return ret;
> > +
> > +       if (device_property_read_bool(dev, "spi-3wire")) {
> > +               ret = regmap_write(data->regmap, ADXL313_REG_DATA_FORMAT,
> > +                                  ADXL313_SPI_3WIRE);
> > +               if (ret)
> > +                       return ret;
> > +       }
> > +
> > +       ret = regmap_read(data->regmap, ADXL313_REG_DEVID0, &regval);
> > +       if (ret)
> > +               return ret;
> > +
> > +       if (regval != ADXL313_DEVID0) {
> > +               dev_err(dev, "Invalid manufacturer ID: 0x%02x\n", regval);
> > +               return -ENODEV;
> > +       }
> > +
> > +       ret = regmap_read(data->regmap, ADXL313_REG_DEVID1, &regval);
> > +       if (ret)
> > +               return ret;
> > +
> > +       if (regval != ADXL313_DEVID1) {
> > +               dev_err(dev, "Invalid mems ID: 0x%02x\n", regval);
> > +               return -ENODEV;
> > +       }
> > +
> > +       ret = regmap_read(data->regmap, ADXL313_REG_PARTID, &regval);
> > +       if (ret)
> > +               return ret;
> > +
> > +       if (regval != ADXL313_PARTID) {
> > +               dev_err(dev, "Invalid device ID: 0x%02x\n", regval);
> > +               return -ENODEV;
> > +       }
> > +
> > +       /* Sets the range to +/- 4g */
> > +       ret = regmap_update_bits(data->regmap, ADXL313_REG_DATA_FORMAT,
> > +                                ADXL313_RANGE_MSK,
> > +                                FIELD_PREP(ADXL313_RANGE_MSK,
> > +                                           ADXL313_RANGE_4G));
> > +       if (ret)
> > +               return ret;
> > +
> > +       /* Enables full resolution */
> > +       ret = regmap_update_bits(data->regmap, ADXL313_REG_DATA_FORMAT,
> > +                                ADXL313_FULL_RES, ADXL313_FULL_RES);
> > +       if (ret)
> > +               return ret;
> > +
> > +       /* Enables measurement mode */
> > +       return regmap_update_bits(data->regmap, ADXL313_REG_POWER_CTL,
> > +                                 ADXL313_POWER_CTL_MSK,
> > +                                 ADXL313_MEASUREMENT_MODE);
> > +}
> > +
> > +int adxl313_core_probe(struct device *dev, struct regmap *regmap,
> > +                      const char *name)
> > +{
> > +       struct adxl313_data *data;
> > +       struct iio_dev *indio_dev;
> > +       int ret;
> > +
> > +       indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
> > +       if (!indio_dev)
> > +               return -ENOMEM;
> > +
> > +       data = iio_priv(indio_dev);
> > +       data->regmap = regmap;
> > +       mutex_init(&data->lock);
> > +
> > +       indio_dev->name = name;
> > +       indio_dev->info = &adxl313_info;
> > +       indio_dev->modes = INDIO_DIRECT_MODE;
> > +       indio_dev->channels = adxl313_channels;
> > +       indio_dev->num_channels = ARRAY_SIZE(adxl313_channels);
> > +
> > +       ret = adxl313_setup(dev, data);
> > +       if (ret) {
> > +               dev_err(dev, "ADXL313 setup failed\n");
> > +               return ret;
> > +       }
> > +
> > +       return devm_iio_device_register(dev, indio_dev);
> > +}
> > +EXPORT_SYMBOL_GPL(adxl313_core_probe);
> > +
> > +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> > +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer core driver");
> > +MODULE_LICENSE("GPL v2");
> > diff --git a/drivers/iio/accel/adxl313_i2c.c b/drivers/iio/accel/adxl313_i2c.c
> > new file mode 100644
> > index 000000000000..65050a2fbd38
> > --- /dev/null
> > +++ b/drivers/iio/accel/adxl313_i2c.c
> > @@ -0,0 +1,65 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * ADXL313 3-Axis Digital Accelerometer
> > + *
> > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > + *
> > + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > + */
> > +
> > +#include <linux/i2c.h>
> > +#include <linux/module.h>
> > +#include <linux/regmap.h>
> > +
> > +#include "adxl313.h"
> > +
> > +static const struct regmap_config adxl313_i2c_regmap_config = {
> > +       .reg_bits       = 8,
> > +       .val_bits       = 8,
> > +       .rd_table       = &adxl313_readable_regs_table,
> > +       .wr_table       = &adxl313_writable_regs_table,
> > +       .max_register   = 0x39
> > +};
> > +
> > +static int adxl313_i2c_probe(struct i2c_client *client)
> > +{
> > +       struct regmap *regmap;
> > +
> > +       regmap = devm_regmap_init_i2c(client, &adxl313_i2c_regmap_config);
> > +       if (IS_ERR(regmap)) {
> > +               dev_err(&client->dev, "Error initializing i2c regmap: %ld\n",
> > +                       PTR_ERR(regmap));
> > +               return PTR_ERR(regmap);
> > +       }
> > +
> > +       return adxl313_core_probe(&client->dev, regmap, client->name);
> > +}
> > +
> > +static const struct i2c_device_id adxl313_i2c_id[] = {
> > +       { "adxl313", 0 },
> > +       { }
> > +};
> > +
> > +MODULE_DEVICE_TABLE(i2c, adxl313_i2c_id);
> > +
> > +static const struct of_device_id adxl313_of_match[] = {
> > +       { .compatible = "adi,adxl313" },
> > +       { },
>
> Since this may be getting a V2 anyway, maybe remove the comma from the
> null-terminators [where the case].
>

Will do, thanks!

> > +};
> > +
> > +MODULE_DEVICE_TABLE(of, adxl313_of_match);
> > +
> > +static struct i2c_driver adxl313_i2c_driver = {
> > +       .driver = {
> > +               .name   = "adxl313_i2c",
> > +               .of_match_table = adxl313_of_match,
> > +       },
> > +       .probe_new      = adxl313_i2c_probe,
> > +       .id_table       = adxl313_i2c_id,
> > +};
> > +
> > +module_i2c_driver(adxl313_i2c_driver);
> > +
> > +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> > +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer I2C driver");
> > +MODULE_LICENSE("GPL v2");
> > diff --git a/drivers/iio/accel/adxl313_spi.c b/drivers/iio/accel/adxl313_spi.c
> > new file mode 100644
> > index 000000000000..7c58c9ff8985
> > --- /dev/null
> > +++ b/drivers/iio/accel/adxl313_spi.c
> > @@ -0,0 +1,74 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * ADXL313 3-Axis Digital Accelerometer
> > + *
> > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > + *
> > + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > + */
> > +
> > +#include <linux/module.h>
> > +#include <linux/regmap.h>
> > +#include <linux/spi/spi.h>
> > +
> > +#include "adxl313.h"
> > +
> > +static const struct regmap_config adxl313_spi_regmap_config = {
> > +       .reg_bits       = 8,
> > +       .val_bits       = 8,
> > +       .rd_table       = &adxl313_readable_regs_table,
> > +       .wr_table       = &adxl313_writable_regs_table,
> > +       .max_register   = 0x39,
> > +        /* Setting bits 7 and 6 enables multiple-byte read */
> > +       .read_flag_mask = BIT(7) | BIT(6)
> > +};
> > +
> > +static int adxl313_spi_probe(struct spi_device *spi)
> > +{
> > +       const struct spi_device_id *id = spi_get_device_id(spi);
> > +       struct regmap *regmap;
> > +       int ret;
> > +
> > +       regmap = devm_regmap_init_spi(spi, &adxl313_spi_regmap_config);
> > +       if (IS_ERR(regmap)) {
> > +               dev_err(&spi->dev, "Error initializing spi regmap: %ld\n",
> > +                       PTR_ERR(regmap));
> > +               return PTR_ERR(regmap);
> > +       }
> > +
> > +       ret = adxl313_core_probe(&spi->dev, regmap, id->name);
> > +       if (ret < 0)
> > +               return ret;
> > +
> > +       return regmap_update_bits(regmap, ADXL313_REG_POWER_CTL,
> > +                                 ADXL313_I2C_DISABLE, ADXL313_I2C_DISABLE);
> > +}
> > +
> > +static const struct spi_device_id adxl313_spi_id[] = {
> > +       { "adxl313", 0 },
> > +       { }
> > +};
> > +
> > +MODULE_DEVICE_TABLE(spi, adxl313_spi_id);
> > +
> > +static const struct of_device_id adxl313_of_match[] = {
> > +       { .compatible = "adi,adxl313" },
> > +       { },
> > +};
> > +
> > +MODULE_DEVICE_TABLE(of, adxl313_of_match);
> > +
> > +static struct spi_driver adxl313_spi_driver = {
> > +       .driver = {
> > +               .name   = "adxl313_spi",
> > +               .of_match_table = adxl313_of_match,
> > +       },
> > +       .probe          = adxl313_spi_probe,
> > +       .id_table       = adxl313_spi_id,
> > +};
> > +
> > +module_spi_driver(adxl313_spi_driver);
> > +
> > +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> > +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer SPI driver");
> > +MODULE_LICENSE("GPL v2");
> > --
> > 2.32.0
> >

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH 2/2] iio: accel: Add driver support for ADXL313
  2021-08-02 17:28       ` Lucas Stankus
@ 2021-08-03  7:15         ` Alexandru Ardelean
  0 siblings, 0 replies; 14+ messages in thread
From: Alexandru Ardelean @ 2021-08-03  7:15 UTC (permalink / raw)
  To: Lucas Stankus
  Cc: Jonathan Cameron, Lars-Peter Clausen, Hennerich, Michael,
	Rob Herring, Bogdan, Dragos, Berghe, Darius, linux-iio,
	devicetree, LKML

On Mon, Aug 2, 2021 at 8:29 PM Lucas Stankus <lucas.p.stankus@gmail.com> wrote:
>
> On Mon, Aug 2, 2021 at 3:57 AM Alexandru Ardelean
> <ardeleanalex@gmail.com> wrote:
> >
> > On Sun, Aug 1, 2021 at 9:09 PM Jonathan Cameron <jic23@kernel.org> wrote:
> > >
> > > On Sat, 31 Jul 2021 17:36:48 -0300
> > > Lucas Stankus <lucas.p.stankus@gmail.com> wrote:
> > >
> > > > ADXL313 is a small, thin, low power, 3-axis accelerometer with high
> > > > resolution measurement up to +/-4g. It includes an integrated 32-level
> > > > FIFO and has activity and inactivity sensing capabilities.
> > > >
> > > > Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > > >
> > > > Signed-off-by: Lucas Stankus <lucas.p.stankus@gmail.com>
> > >
> > > Very nice.  A few really minor things inline.
> > >
> > > Jonathan
> > >
> > > > ---
> > > >  MAINTAINERS                      |   9 +
> > > >  drivers/iio/accel/Kconfig        |  29 +++
> > > >  drivers/iio/accel/Makefile       |   3 +
> > > >  drivers/iio/accel/adxl313.h      |  60 ++++++
> > > >  drivers/iio/accel/adxl313_core.c | 323 +++++++++++++++++++++++++++++++
> > > >  drivers/iio/accel/adxl313_i2c.c  |  65 +++++++
> > > >  drivers/iio/accel/adxl313_spi.c  |  74 +++++++
> > > >  7 files changed, 563 insertions(+)
> > > >  create mode 100644 drivers/iio/accel/adxl313.h
> > > >  create mode 100644 drivers/iio/accel/adxl313_core.c
> > > >  create mode 100644 drivers/iio/accel/adxl313_i2c.c
> > > >  create mode 100644 drivers/iio/accel/adxl313_spi.c
> > > >
> > > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > > index a61f4f3b78a9..1fc88723e632 100644
> > > > --- a/MAINTAINERS
> > > > +++ b/MAINTAINERS
> > > > @@ -585,6 +585,15 @@ L:       platform-driver-x86@vger.kernel.org
> > > >  S:   Maintained
> > > >  F:   drivers/platform/x86/adv_swbutton.c
> > > >
> > > > +ADXL313 THREE-AXIS DIGITAL ACCELEROMETER DRIVER
> > > > +M:   Lucas Stankus <lucas.p.stankus@gmail.com>
> > > > +S:   Supported
> > > > +F:   Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml
> > > > +F:   drivers/iio/accel/adxl313.h
> > > > +F:   drivers/iio/accel/adxl313_core.c
> > > > +F:   drivers/iio/accel/adxl313_i2c.c
> > > > +F:   drivers/iio/accel/adxl313_spi.c
> > > > +
> > > >  ADXL34X THREE-AXIS DIGITAL ACCELEROMETER DRIVER (ADXL345/ADXL346)
> > > >  M:   Michael Hennerich <michael.hennerich@analog.com>
> > > >  S:   Supported
> > > > diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
> > > > index 0e56ace61103..ae621532e716 100644
> > > > --- a/drivers/iio/accel/Kconfig
> > > > +++ b/drivers/iio/accel/Kconfig
> > > > @@ -30,6 +30,35 @@ config ADIS16209
> > > >         To compile this driver as a module, say M here: the module will be
> > > >         called adis16209.
> > > >
> > > > +config ADXL313
> > > > +     tristate
> > > > +
> > > > +config ADXL313_I2C
> > > > +     tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer I2C Driver"
> > > > +     depends on I2C
> > > > +     select ADXL313
> > > > +     select REGMAP_I2C
> > > > +     help
> > > > +       Say Y here if you want to build i2c support for the Analog Devices
> > > > +       ADXL313 3-axis digital accelerometer.
> > > > +
> > > > +       To compile this driver as a module, choose M here: the module
> > > > +       will be called adxl313_i2c and you will also get adxl313_core
> > > > +       for the core module.
> > > > +
> > > > +config ADXL313_SPI
> > > > +     tristate "Analog Devices ADXL313 3-Axis Digital Accelerometer SPI Driver"
> > > > +     depends on SPI
> > > > +     select ADXL313
> > > > +     select REGMAP_SPI
> > > > +     help
> > > > +       Say Y here if you want to build spi support for the Analog Devices
> > > > +       ADXL313 3-axis digital accelerometer.
> > > > +
> > > > +       To compile this driver as a module, choose M here: the module
> > > > +       will be called adxl313_spi and you will also get adxl313_core
> > > > +       for the core module.
> > > > +
> > > >  config ADXL345
> > > >       tristate
> > > >
> > > > diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
> > > > index 89280e823bcd..fadc92816e24 100644
> > > > --- a/drivers/iio/accel/Makefile
> > > > +++ b/drivers/iio/accel/Makefile
> > > > @@ -6,6 +6,9 @@
> > > >  # When adding new entries keep the list in alphabetical order
> > > >  obj-$(CONFIG_ADIS16201) += adis16201.o
> > > >  obj-$(CONFIG_ADIS16209) += adis16209.o
> > > > +obj-$(CONFIG_ADXL313) += adxl313_core.o
> > > > +obj-$(CONFIG_ADXL313_I2C) += adxl313_i2c.o
> > > > +obj-$(CONFIG_ADXL313_SPI) += adxl313_spi.o
> > > >  obj-$(CONFIG_ADXL345) += adxl345_core.o
> > > >  obj-$(CONFIG_ADXL345_I2C) += adxl345_i2c.o
> > > >  obj-$(CONFIG_ADXL345_SPI) += adxl345_spi.o
> > > > diff --git a/drivers/iio/accel/adxl313.h b/drivers/iio/accel/adxl313.h
> > > > new file mode 100644
> > > > index 000000000000..72f268e02a80
> > > > --- /dev/null
> > > > +++ b/drivers/iio/accel/adxl313.h
> > > > @@ -0,0 +1,60 @@
> > > > +/* SPDX-License-Identifier: GPL-2.0-only */
> > > > +/*
> > > > + * ADXL313 3-Axis Digital Accelerometer
> > > > + *
> > > > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > > > + */
> > > > +
> > > > +#ifndef _ADXL313_H_
> > > > +#define _ADXL313_H_
> > > > +
> > > > +/* ADXL313 register definitions */
> > >
> > > If these are only used in the c file, push them down there. Better to
> > > keep what is in the header to absolute minimum.
> > > however I suggest below moving some of this so that won't be true any more,
> > > so maybe you do want to keep them here!
> > >
> > >
> > > > +#define ADXL313_REG_DEVID0           0x00
> > > > +#define ADXL313_REG_DEVID1           0x01
> > > > +#define ADXL313_REG_PARTID           0x02
> > > > +#define ADXL313_REG_XID                      0x04
> > > > +#define ADXL313_REG_SOFT_RESET               0x18
> > > > +#define ADXL313_REG_OFS_AXIS(index)  (0x1E + (index))
> > > > +#define ADXL313_REG_THRESH_ACT               0x24
> > > > +#define ADXL313_REG_ACT_INACT_CTL    0x27
> > > > +#define ADXL313_REG_BW_RATE          0x2C
> > > > +#define ADXL313_REG_POWER_CTL                0x2D
> > > > +#define ADXL313_REG_INT_MAP          0x2F
> > > > +#define ADXL313_REG_DATA_FORMAT              0x31
> > > > +#define ADXL313_REG_DATAX            0x32
> > > > +#define ADXL313_REG_DATAY            0x34
> > > > +#define ADXL313_REG_DATAZ            0x36
> > > > +#define ADXL313_REG_FIFO_CTL         0x38
> > > > +#define ADXL313_REG_FIFO_STATUS              0x39
> > > > +
> > > > +#define ADXL313_DEVID0                       0xAD
> > > > +#define ADXL313_DEVID1                       0x1D
> > > > +#define ADXL313_PARTID                       0xCB
> > > > +#define ADXL313_SOFT_RESET           0x52
> > > > +
> > > > +#define ADXL313_RATE_MSK             GENMASK(3, 0)
> > > > +#define ADXL313_RATE_BASE            6
> > > > +
> > > > +#define ADXL313_POWER_CTL_MSK                GENMASK(3, 2)
> > > > +#define ADXL313_MEASUREMENT_MODE     BIT(3)
> > > > +
> > > > +#define ADXL313_RANGE_MSK            GENMASK(1, 0)
> > > > +#define ADXL313_RANGE_4G             3
> > > > +
> > > > +#define ADXL313_FULL_RES             BIT(3)
> > > > +#define ADXL313_SPI_3WIRE            BIT(6)
> > > > +#define ADXL313_I2C_DISABLE          BIT(6)
> > > > +
> > > > +/*
> > > > + * Scale for any g range is given in datasheet as
> > > > + * 1024 LSB/g = 0.0009765625 * 9.80665 = 0.009576806640625 m/s^2
> > > > + */
> > > > +#define ADXL313_NSCALE 9576806
> > > > +
> > > > +extern const struct regmap_access_table adxl313_readable_regs_table;
> > > > +
> > > > +extern const struct regmap_access_table adxl313_writable_regs_table;
> > > > +
> > > > +int adxl313_core_probe(struct device *dev, struct regmap *regmap,
> > > > +                    const char *name);
> > > > +#endif /* _ADXL313_H_ */
> > > > diff --git a/drivers/iio/accel/adxl313_core.c b/drivers/iio/accel/adxl313_core.c
> > > > new file mode 100644
> > > > index 000000000000..76382ab4f0f4
> > > > --- /dev/null
> > > > +++ b/drivers/iio/accel/adxl313_core.c
> > > > @@ -0,0 +1,323 @@
> > > > +// SPDX-License-Identifier: GPL-2.0-only
> > > > +/*
> > > > + * ADXL313 3-Axis Digital Accelerometer
> > > > + *
> > > > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > > > + *
> > > > + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > > > + */
> > > > +
> > > > +#include <linux/bitfield.h>
> > > > +#include <linux/iio/iio.h>
> > > > +#include <linux/module.h>
> > > > +#include <linux/regmap.h>
> > > > +
> > > > +#include "adxl313.h"
> > > > +
> > > > +const struct regmap_range adxl313_readable_reg_range[] = {
> > > > +     regmap_reg_range(ADXL313_REG_DEVID0, ADXL313_REG_XID),
> > > > +     regmap_reg_range(ADXL313_REG_SOFT_RESET, ADXL313_REG_SOFT_RESET),
> > > > +     regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
> > > > +     regmap_reg_range(ADXL313_REG_THRESH_ACT, ADXL313_REG_ACT_INACT_CTL),
> > > > +     regmap_reg_range(ADXL313_REG_BW_RATE, ADXL313_REG_FIFO_STATUS)
> > > > +};
> > > > +
> > > > +const struct regmap_access_table adxl313_readable_regs_table = {
> > > > +     .yes_ranges = adxl313_readable_reg_range,
> > > > +     .n_yes_ranges = ARRAY_SIZE(adxl313_readable_reg_range)
> > > > +};
> > > > +EXPORT_SYMBOL_GPL(adxl313_readable_regs_table);
> > > > +
> > > > +const struct regmap_range adxl313_writable_reg_range[] = {
> > > > +     regmap_reg_range(ADXL313_REG_SOFT_RESET, ADXL313_REG_SOFT_RESET),
> > > > +     regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
> > > > +     regmap_reg_range(ADXL313_REG_THRESH_ACT, ADXL313_REG_ACT_INACT_CTL),
> > > > +     regmap_reg_range(ADXL313_REG_BW_RATE, ADXL313_REG_INT_MAP),
> > > > +     regmap_reg_range(ADXL313_REG_DATA_FORMAT, ADXL313_REG_DATA_FORMAT),
> > > > +     regmap_reg_range(ADXL313_REG_FIFO_CTL, ADXL313_REG_FIFO_CTL)
> > > > +};
> > > > +
> > > > +const struct regmap_access_table adxl313_writable_regs_table = {
> > > > +     .yes_ranges = adxl313_writable_reg_range,
> > > > +     .n_yes_ranges = ARRAY_SIZE(adxl313_writable_reg_range)
> > > > +};
> > > > +EXPORT_SYMBOL_GPL(adxl313_writable_regs_table);
> > > > +
> > > > +struct adxl313_data {
> > > > +     struct regmap   *regmap;
> > > > +     struct mutex    lock; /* lock to protect transf_buf */
> > > > +     __le16          transf_buf ____cacheline_aligned;
> > > > +};
> > > > +
> > > > +static const int adxl313_odr_freqs[][2] = {
> > > > +     [0] = { 6, 250000 },
> > > > +     [1] = { 12, 500000 },
> > > > +     [2] = { 25, 0 },
> > > > +     [3] = { 50, 0 },
> > > > +     [4] = { 100, 0 },
> > > > +     [5] = { 200, 0 },
> > > > +     [6] = { 400, 0 },
> > > > +     [7] = { 800, 0 },
> > > > +     [8] = { 1600, 0 },
> > > > +     [9] = { 3200, 0 },
> > > > +};
> > > > +
> > > > +#define ADXL313_ACCEL_CHANNEL(index, addr, axis) {                   \
> > > > +     .type = IIO_ACCEL,                                              \
> > > > +     .address = addr,                                                \
> > > > +     .modified = 1,                                                  \
> > > > +     .channel2 = IIO_MOD_##axis,                                     \
> > > > +     .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |                  \
> > > > +                           BIT(IIO_CHAN_INFO_CALIBBIAS),             \
> > > > +     .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |          \
> > > > +                                 BIT(IIO_CHAN_INFO_SAMP_FREQ),       \
> > > > +     .info_mask_shared_by_type_available =                           \
> > > > +             BIT(IIO_CHAN_INFO_SAMP_FREQ),                           \
> > > > +     .scan_index = index,                                            \
> > > > +     .scan_type = {                                                  \
> > > > +             .sign = 's',                                            \
> > > > +             .realbits = 13,                                         \
> > > > +             .storagebits = 16,                                      \
> > > > +             .endianness = IIO_LE,                                   \
> > > > +     },                                                              \
> > > > +}
> > > > +
> > > > +static const struct iio_chan_spec adxl313_channels[] = {
> > > > +     ADXL313_ACCEL_CHANNEL(0, ADXL313_REG_DATAX, X),
> > > > +     ADXL313_ACCEL_CHANNEL(1, ADXL313_REG_DATAY, Y),
> > > > +     ADXL313_ACCEL_CHANNEL(2, ADXL313_REG_DATAZ, Z),
> > > > +};
> > > > +
> > > > +static int adxl313_set_odr(struct adxl313_data *data,
> > > > +                        unsigned int freq1, unsigned int freq2)
> > > > +{
> > > > +     unsigned int i;
> > > > +
> > > > +     for (i = 0; i < ARRAY_SIZE(adxl313_odr_freqs); i++) {
> > > > +             if (adxl313_odr_freqs[i][0] == freq1 &&
> > > > +                 adxl313_odr_freqs[i][1] == freq2)
> > > > +                     break;
> > > > +     }
> > > > +
> > > > +     if (i == ARRAY_SIZE(adxl313_odr_freqs))
> > > > +             return -EINVAL;
> > > > +
> > > > +     return regmap_update_bits(data->regmap, ADXL313_REG_BW_RATE,
> > > > +                               ADXL313_RATE_MSK,
> > > > +                               FIELD_PREP(ADXL313_RATE_MSK,
> > > > +                                          ADXL313_RATE_BASE + i));
> > > > +}
> > > > +
> > > > +static int adxl313_read_axis(struct adxl313_data *data,
> > > > +                          struct iio_chan_spec const *chan)
> > > > +{
> > > > +     int ret;
> > > > +
> > > > +     mutex_lock(&data->lock);
> > > > +
> > > > +     ret = regmap_bulk_read(data->regmap,
> > > > +                            chan->address,
> > > > +                            &data->transf_buf, 2);
> > > > +     if (ret)
> > > > +             goto unlock_ret;
> > > > +
> > > > +     ret = le16_to_cpu(data->transf_buf);
> > > > +
> > > > +unlock_ret:
> > > > +     mutex_unlock(&data->lock);
> > > > +     return ret;
> > > > +}
> > > > +
> > > > +static int adxl313_read_freq_avail(struct iio_dev *indio_dev,
> > > > +                                struct iio_chan_spec const *chan,
> > > > +                                const int **vals, int *type, int *length,
> > > > +                                long mask)
> > > > +{
> > > > +     switch (mask) {
> > > > +     case IIO_CHAN_INFO_SAMP_FREQ:
> > > > +             *vals = (const int *)adxl313_odr_freqs;
> > > > +             *length = ARRAY_SIZE(adxl313_odr_freqs) * 2;
> > > > +             *type = IIO_VAL_INT_PLUS_MICRO;
> > > > +             return IIO_AVAIL_LIST;
> > > > +     }
> > > > +
> > > > +     return -EINVAL;
> > > > +}
> > > > +
> > > > +static int adxl313_read_raw(struct iio_dev *indio_dev,
> > > > +                         struct iio_chan_spec const *chan,
> > > > +                         int *val, int *val2, long mask)
> > > > +{
> > > > +     struct adxl313_data *data = iio_priv(indio_dev);
> > > > +     unsigned int regval;
> > > > +     int ret;
> > > > +
> > > > +     switch (mask) {
> > > > +     case IIO_CHAN_INFO_RAW:
> > > > +             ret = adxl313_read_axis(data, chan);
> > > > +             if (ret < 0)
> > > > +                     return ret;
> > > > +
> > > > +             *val = sign_extend32(ret, chan->scan_type.realbits - 1);
> > > > +             return IIO_VAL_INT;
> > > > +     case IIO_CHAN_INFO_SCALE:
> > > > +             *val = 0;
> > > > +             *val2 = ADXL313_NSCALE;
> > > > +             return IIO_VAL_INT_PLUS_NANO;
> > > > +     case IIO_CHAN_INFO_CALIBBIAS:
> > > > +             ret = regmap_read(data->regmap,
> > > > +                               ADXL313_REG_OFS_AXIS(chan->scan_index),
> > > > +                               &regval);
> > > > +             if (ret)
> > > > +                     return ret;
> > > > +
> > > > +             /*
> > > > +              * 8-bit resolution at +/- 0.5g, that is 4x accel data scale
> > > > +              * factor at full resolution
> > > > +              */
> > > > +             *val = sign_extend32(regval, 7) * 4;
> > > > +             return IIO_VAL_INT;
> > > > +     case IIO_CHAN_INFO_SAMP_FREQ:
> > > > +             ret = regmap_read(data->regmap, ADXL313_REG_BW_RATE, &regval);
> > > > +             if (ret)
> > > > +                     return ret;
> > > > +
> > > > +             ret = FIELD_GET(ADXL313_RATE_MSK, regval) - ADXL313_RATE_BASE;
> > > > +             *val = adxl313_odr_freqs[ret][0];
> > > > +             *val2 = adxl313_odr_freqs[ret][1];
> > > > +             return IIO_VAL_INT_PLUS_MICRO;
> > > > +     }
> > > > +
> > > > +     return -EINVAL;
> > > > +}
> > > > +
> > > > +static int adxl313_write_raw(struct iio_dev *indio_dev,
> > > > +                          struct iio_chan_spec const *chan,
> > > > +                          int val, int val2, long mask)
> > > > +{
> > > > +     struct adxl313_data *data = iio_priv(indio_dev);
> > > > +
> > > > +     switch (mask) {
> > > > +     case IIO_CHAN_INFO_CALIBBIAS:
> > > > +             /*
> > > > +              * 8-bit resolution at +/- 0.5g, that is 4x accel data scale
> > > > +              * factor at full resolution
> > > > +              */
> > > > +             if (val > 127 * 4 || val < -128 * 4)
> > > > +                     return -EINVAL;
> > > > +
> > > > +             return regmap_write(data->regmap,
> > > > +                                 ADXL313_REG_OFS_AXIS(chan->scan_index),
> > > > +                                 val / 4);
> > > > +     case IIO_CHAN_INFO_SAMP_FREQ:
> > > > +             return adxl313_set_odr(data, val, val2);
> > > > +     }
> > > > +
> > > > +     return -EINVAL;
> > >
> > > Put this as a default in the case otherwise you might get warnings saying you
> > > don't handle all the possible values.
> > >
> > > > +}
> > > > +
> > > > +static const struct iio_info adxl313_info = {
> > > > +     .read_raw       = adxl313_read_raw,
> > > > +     .write_raw      = adxl313_write_raw,
> > > > +     .read_avail     = adxl313_read_freq_avail
> > > > +};
> > > > +
> > > > +static int adxl313_setup(struct device *dev, struct adxl313_data *data)
> > > > +{
> > > > +     unsigned int regval;
> > > > +     int ret;
> > > > +
> > > > +     /* Ensures the device is in a consistent state after start up */
> > > > +     ret = regmap_write(data->regmap, ADXL313_REG_SOFT_RESET,
> > > > +                        ADXL313_SOFT_RESET);
> > > > +     if (ret)
> > > > +             return ret;
> > > > +
> > > > +     if (device_property_read_bool(dev, "spi-3wire")) {
> > >
> > > Rather odd to see spi specific stuff in here.  Perhaps provide a callback to
> > > common probe if it needs to be done at this point in bringing the device up.
> > > However, I think you can just do this before calling the common_probe()
> >
> > This is a recurring theme in some ADI chips, where the chip supports
> > both 3wire and 4wire SPI modes.
> >
> > But this has some tendency to create confusion and a bit duplication.
> > Because "spi-3wire" is also valid in `drivers/spi/spi.c` in the SPI framework.
> > So, it gets parsed [only for OF] by the SPI framework [hence the duplication].
> > But, then,if the SPI controller doesn't support 3wire mode, this
> > setting gets invalidated inside the SPI framework; the chip remains in
> > 3wire mode anyway.
> >
> > [if the above happens] This setting can work if there is a passive
> > SPI-mode converter [from 4wire to 3wire]
> > Which is not a great way to describe the HW, but it's the best we can
> > do for now.
> >
>
> Thanks for the insight.
>
> Would it be better to drop 3wire support then? I believe that there
> isn't much of a loss in not supporting 3wire when 4wire is already
> working, so I think that writing a converter wouldn't be worth the
> effort in this case.

3wire mode is useful for boards that want to reduce wiring.
I'd leave support for 3wire in this driver.
Another way to do it would be to check `spi->mode & SPI_3WIRE`.
In this case, the SPI framework has parsed the "spi-3wire" DT option
and has done the validation that the SPI controller can do 3wire.

Not sure what Jonathan would prefer.

>
> > This comes back to an older discussion about overriding spi-cpol &
> > spi-cpha in the DT in case there are some weird board designs.
> > The driver would specify some mode, but the DT could override it, in
> > case it is needed.
> > I had a plan to do a general approach for this, but did not get to it.
> >
> > >
> > > > +             ret = regmap_write(data->regmap, ADXL313_REG_DATA_FORMAT,
> > > > +                                ADXL313_SPI_3WIRE);
> > > > +             if (ret)
> > > > +                     return ret;
> > > > +     }
> > > > +
> > > > +     ret = regmap_read(data->regmap, ADXL313_REG_DEVID0, &regval);
> > > > +     if (ret)
> > > > +             return ret;
> > > > +
> > > > +     if (regval != ADXL313_DEVID0) {
> > > > +             dev_err(dev, "Invalid manufacturer ID: 0x%02x\n", regval);
> > > > +             return -ENODEV;
> > > > +     }
> > > > +
> > > > +     ret = regmap_read(data->regmap, ADXL313_REG_DEVID1, &regval);
> > > > +     if (ret)
> > > > +             return ret;
> > > > +
> > > > +     if (regval != ADXL313_DEVID1) {
> > > > +             dev_err(dev, "Invalid mems ID: 0x%02x\n", regval);
> > > > +             return -ENODEV;
> > > > +     }
> > > > +
> > > > +     ret = regmap_read(data->regmap, ADXL313_REG_PARTID, &regval);
> > > > +     if (ret)
> > > > +             return ret;
> > > > +
> > > > +     if (regval != ADXL313_PARTID) {
> > > > +             dev_err(dev, "Invalid device ID: 0x%02x\n", regval);
> > > > +             return -ENODEV;
> > > > +     }
> > > > +
> > > > +     /* Sets the range to +/- 4g */
> > > > +     ret = regmap_update_bits(data->regmap, ADXL313_REG_DATA_FORMAT,
> > > > +                              ADXL313_RANGE_MSK,
> > > > +                              FIELD_PREP(ADXL313_RANGE_MSK,
> > > > +                                         ADXL313_RANGE_4G));
> > > > +     if (ret)
> > > > +             return ret;
> > > > +
> > > > +     /* Enables full resolution */
> > > > +     ret = regmap_update_bits(data->regmap, ADXL313_REG_DATA_FORMAT,
> > > > +                              ADXL313_FULL_RES, ADXL313_FULL_RES);
> > > > +     if (ret)
> > > > +             return ret;
> > > > +
> > > > +     /* Enables measurement mode */
> > > > +     return regmap_update_bits(data->regmap, ADXL313_REG_POWER_CTL,
> > > > +                               ADXL313_POWER_CTL_MSK,
> > > > +                               ADXL313_MEASUREMENT_MODE);
> > > > +}
> > > > +
> > > > +int adxl313_core_probe(struct device *dev, struct regmap *regmap,
> > > > +                    const char *name)
> > > > +{
> > > > +     struct adxl313_data *data;
> > > > +     struct iio_dev *indio_dev;
> > > > +     int ret;
> > > > +
> > > > +     indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
> > > > +     if (!indio_dev)
> > > > +             return -ENOMEM;
> > > > +
> > > > +     data = iio_priv(indio_dev);
> > > > +     data->regmap = regmap;
> > > > +     mutex_init(&data->lock);
> > > > +
> > > > +     indio_dev->name = name;
> > > > +     indio_dev->info = &adxl313_info;
> > > > +     indio_dev->modes = INDIO_DIRECT_MODE;
> > > > +     indio_dev->channels = adxl313_channels;
> > > > +     indio_dev->num_channels = ARRAY_SIZE(adxl313_channels);
> > > > +
> > > > +     ret = adxl313_setup(dev, data);
> > > > +     if (ret) {
> > > > +             dev_err(dev, "ADXL313 setup failed\n");
> > > > +             return ret;
> > > > +     }
> > > > +
> > > > +     return devm_iio_device_register(dev, indio_dev);
> > > > +}
> > > > +EXPORT_SYMBOL_GPL(adxl313_core_probe);
> > > > +
> > > > +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> > > > +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer core driver");
> > > > +MODULE_LICENSE("GPL v2");
> > > > diff --git a/drivers/iio/accel/adxl313_i2c.c b/drivers/iio/accel/adxl313_i2c.c
> > > > new file mode 100644
> > > > index 000000000000..65050a2fbd38
> > > > --- /dev/null
> > > > +++ b/drivers/iio/accel/adxl313_i2c.c
> > > > @@ -0,0 +1,65 @@
> > > > +// SPDX-License-Identifier: GPL-2.0-only
> > > > +/*
> > > > + * ADXL313 3-Axis Digital Accelerometer
> > > > + *
> > > > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > > > + *
> > > > + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > > > + */
> > > > +
> > > > +#include <linux/i2c.h>
> > > > +#include <linux/module.h>
> > > > +#include <linux/regmap.h>
> > > > +
> > > > +#include "adxl313.h"
> > > > +
> > > > +static const struct regmap_config adxl313_i2c_regmap_config = {
> > > > +     .reg_bits       = 8,
> > > > +     .val_bits       = 8,
> > > > +     .rd_table       = &adxl313_readable_regs_table,
> > > > +     .wr_table       = &adxl313_writable_regs_table,
> > > > +     .max_register   = 0x39
> > > > +};
> > > > +
> > > > +static int adxl313_i2c_probe(struct i2c_client *client)
> > > > +{
> > > > +     struct regmap *regmap;
> > > > +
> > > > +     regmap = devm_regmap_init_i2c(client, &adxl313_i2c_regmap_config);
> > > > +     if (IS_ERR(regmap)) {
> > > > +             dev_err(&client->dev, "Error initializing i2c regmap: %ld\n",
> > > > +                     PTR_ERR(regmap));
> > > > +             return PTR_ERR(regmap);
> > > > +     }
> > > > +
> > > > +     return adxl313_core_probe(&client->dev, regmap, client->name);
> > > > +}
> > > > +
> > > > +static const struct i2c_device_id adxl313_i2c_id[] = {
> > > > +     { "adxl313", 0 },
> > >
> > > No real need to set the data value if it's just going to be 0.
> > >         { "adl313 },
> > > is fine.
> > >
> > > > +     { }
> > > > +};
> > > > +
> > > > +MODULE_DEVICE_TABLE(i2c, adxl313_i2c_id);
> > > > +
> > > > +static const struct of_device_id adxl313_of_match[] = {
> > > > +     { .compatible = "adi,adxl313" },
> > > > +     { },
> > > > +};
> > > > +
> > > > +MODULE_DEVICE_TABLE(of, adxl313_of_match);
> > > > +
> > > > +static struct i2c_driver adxl313_i2c_driver = {
> > > > +     .driver = {
> > > > +             .name   = "adxl313_i2c",
> > > > +             .of_match_table = adxl313_of_match,
> > > > +     },
> > > > +     .probe_new      = adxl313_i2c_probe,
> > > > +     .id_table       = adxl313_i2c_id,
> > > > +};
> > > > +
> > > > +module_i2c_driver(adxl313_i2c_driver);
> > > > +
> > > > +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> > > > +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer I2C driver");
> > > > +MODULE_LICENSE("GPL v2");
> > > > diff --git a/drivers/iio/accel/adxl313_spi.c b/drivers/iio/accel/adxl313_spi.c
> > > > new file mode 100644
> > > > index 000000000000..7c58c9ff8985
> > > > --- /dev/null
> > > > +++ b/drivers/iio/accel/adxl313_spi.c
> > > > @@ -0,0 +1,74 @@
> > > > +// SPDX-License-Identifier: GPL-2.0-only
> > > > +/*
> > > > + * ADXL313 3-Axis Digital Accelerometer
> > > > + *
> > > > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > > > + *
> > > > + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > > > + */
> > > > +
> > > > +#include <linux/module.h>
> > > > +#include <linux/regmap.h>
> > > > +#include <linux/spi/spi.h>
> > > > +
> > > > +#include "adxl313.h"
> > > > +
> > > > +static const struct regmap_config adxl313_spi_regmap_config = {
> > > > +     .reg_bits       = 8,
> > > > +     .val_bits       = 8,
> > > > +     .rd_table       = &adxl313_readable_regs_table,
> > > > +     .wr_table       = &adxl313_writable_regs_table,
> > > > +     .max_register   = 0x39,
> > > > +      /* Setting bits 7 and 6 enables multiple-byte read */
> > > > +     .read_flag_mask = BIT(7) | BIT(6)
> > > > +};
> > > > +
> > > > +static int adxl313_spi_probe(struct spi_device *spi)
> > > > +{
> > > > +     const struct spi_device_id *id = spi_get_device_id(spi);
> > > > +     struct regmap *regmap;
> > > > +     int ret;
> > > > +
> > > > +     regmap = devm_regmap_init_spi(spi, &adxl313_spi_regmap_config);
> > > > +     if (IS_ERR(regmap)) {
> > > > +             dev_err(&spi->dev, "Error initializing spi regmap: %ld\n",
> > > > +                     PTR_ERR(regmap));
> > > > +             return PTR_ERR(regmap);
> > > > +     }
> > > > +
> > > > +     ret = adxl313_core_probe(&spi->dev, regmap, id->name);
> > > > +     if (ret < 0)
> > > > +             return ret;
> > > > +
> > > > +     return regmap_update_bits(regmap, ADXL313_REG_POWER_CTL,
> > > > +                               ADXL313_I2C_DISABLE, ADXL313_I2C_DISABLE);
> > >
> > > Why is this only done after the rest of probe?  Needs a comment perhaps.
> > > Normally I'd expect the core probe and hence exposure of the device
> > > to userspace etc to be the last thing done.
> > >
> > > > +}
> > > > +
> > > > +static const struct spi_device_id adxl313_spi_id[] = {
> > > > +     { "adxl313", 0 },
> > > > +     { }
> > > > +};
> > > > +
> > > > +MODULE_DEVICE_TABLE(spi, adxl313_spi_id);
> > > > +
> > > > +static const struct of_device_id adxl313_of_match[] = {
> > > > +     { .compatible = "adi,adxl313" },
> > > > +     { },
> > > > +};
> > > > +
> > > > +MODULE_DEVICE_TABLE(of, adxl313_of_match);
> > > > +
> > > > +static struct spi_driver adxl313_spi_driver = {
> > > > +     .driver = {
> > > > +             .name   = "adxl313_spi",
> > > > +             .of_match_table = adxl313_of_match,
> > > > +     },
> > > > +     .probe          = adxl313_spi_probe,
> > > > +     .id_table       = adxl313_spi_id,
> > > > +};
> > > > +
> > > > +module_spi_driver(adxl313_spi_driver);
> > > > +
> > > > +MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
> > > > +MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer SPI driver");
> > > > +MODULE_LICENSE("GPL v2");
> > >

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH 2/2] iio: accel: Add driver support for ADXL313
  2021-08-02 17:15     ` Lucas Stankus
@ 2021-08-03 17:18       ` Jonathan Cameron
  0 siblings, 0 replies; 14+ messages in thread
From: Jonathan Cameron @ 2021-08-03 17:18 UTC (permalink / raw)
  To: Lucas Stankus
  Cc: Jonathan Cameron, Lars-Peter Clausen, Hennerich, Michael,
	robh+dt, Bogdan, Dragos, Berghe, Darius, linux-iio, devicetree,
	Linux Kernel Mailing List

On Mon, 2 Aug 2021 14:15:53 -0300
Lucas Stankus <lucas.p.stankus@gmail.com> wrote:

> On Sun, Aug 1, 2021 at 3:09 PM Jonathan Cameron <jic23@kernel.org> wrote:
> >
> > On Sat, 31 Jul 2021 17:36:48 -0300
> > Lucas Stankus <lucas.p.stankus@gmail.com> wrote:
> >  
> > > ADXL313 is a small, thin, low power, 3-axis accelerometer with high
> > > resolution measurement up to +/-4g. It includes an integrated 32-level
> > > FIFO and has activity and inactivity sensing capabilities.
> > >
> > > Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > >
> > > Signed-off-by: Lucas Stankus <lucas.p.stankus@gmail.com>  
> >
> > Very nice.  A few really minor things inline.
> >
> > Jonathan
> >  
> 
> Thanks for the feedback!
> 
> I'll change the minor things for the v2.
> 

...

> > > +
> > > +static int adxl313_setup(struct device *dev, struct adxl313_data *data)
> > > +{
> > > +     unsigned int regval;
> > > +     int ret;
> > > +
> > > +     /* Ensures the device is in a consistent state after start up */
> > > +     ret = regmap_write(data->regmap, ADXL313_REG_SOFT_RESET,
> > > +                        ADXL313_SOFT_RESET);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     if (device_property_read_bool(dev, "spi-3wire")) {  
> >
> > Rather odd to see spi specific stuff in here.  Perhaps provide a callback to
> > common probe if it needs to be done at this point in bringing the device up.
> > However, I think you can just do this before calling the common_probe()
> >  
> 
> I'm doing this here because of the device reset, so whatever I write
> to the register before it would be overwritten in setup. The datasheet
> doesn't say that resetting the device is strictly necessary, but I
> figured it would be better to do so to force consistency.
> 
> If I drop the reset, I'd be able to do it before the core probe call
> and, from what I'm seeing here, the startup seems to be consistent
> without it. Do you think it's best to drop the device reset?
Ah. I'd missed that.  Fair enough.

In this case, I'd pass in a function pointer from the spi module. If the
function pointer is provided, call it to spi specific setup, if NULL
don't call it (so we don't need to provide an empty stub in the i2c side of things).

> 
> > > +             ret = regmap_write(data->regmap, ADXL313_REG_DATA_FORMAT,
> > > +                                ADXL313_SPI_3WIRE);
> > > +             if (ret)
> > > +                     return ret;
> > > +     }
> > > +
> > > +     ret = regmap_read(data->regmap, ADXL313_REG_DEVID0, &regval);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     if (regval != ADXL313_DEVID0) {
> > > +             dev_err(dev, "Invalid manufacturer ID: 0x%02x\n", regval);
> > > +             return -ENODEV;
> > > +     }
> > > +
> > > +     ret = regmap_read(data->regmap, ADXL313_REG_DEVID1, &regval);
> > > +     if (ret)
> > > +             return ret;
> > > +

...

> > > diff --git a/drivers/iio/accel/adxl313_spi.c b/drivers/iio/accel/adxl313_spi.c
> > > new file mode 100644
> > > index 000000000000..7c58c9ff8985
> > > --- /dev/null
> > > +++ b/drivers/iio/accel/adxl313_spi.c
> > > @@ -0,0 +1,74 @@
> > > +// SPDX-License-Identifier: GPL-2.0-only
> > > +/*
> > > + * ADXL313 3-Axis Digital Accelerometer
> > > + *
> > > + * Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
> > > + *
> > > + * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
> > > + */
> > > +
> > > +#include <linux/module.h>
> > > +#include <linux/regmap.h>
> > > +#include <linux/spi/spi.h>
> > > +
> > > +#include "adxl313.h"
> > > +
> > > +static const struct regmap_config adxl313_spi_regmap_config = {
> > > +     .reg_bits       = 8,
> > > +     .val_bits       = 8,
> > > +     .rd_table       = &adxl313_readable_regs_table,
> > > +     .wr_table       = &adxl313_writable_regs_table,
> > > +     .max_register   = 0x39,
> > > +      /* Setting bits 7 and 6 enables multiple-byte read */
> > > +     .read_flag_mask = BIT(7) | BIT(6)
> > > +};
> > > +
> > > +static int adxl313_spi_probe(struct spi_device *spi)
> > > +{
> > > +     const struct spi_device_id *id = spi_get_device_id(spi);
> > > +     struct regmap *regmap;
> > > +     int ret;
> > > +
> > > +     regmap = devm_regmap_init_spi(spi, &adxl313_spi_regmap_config);
> > > +     if (IS_ERR(regmap)) {
> > > +             dev_err(&spi->dev, "Error initializing spi regmap: %ld\n",
> > > +                     PTR_ERR(regmap));
> > > +             return PTR_ERR(regmap);
> > > +     }
> > > +
> > > +     ret = adxl313_core_probe(&spi->dev, regmap, id->name);
> > > +     if (ret < 0)
> > > +             return ret;
> > > +
> > > +     return regmap_update_bits(regmap, ADXL313_REG_POWER_CTL,
> > > +                               ADXL313_I2C_DISABLE, ADXL313_I2C_DISABLE);  
> >
> > Why is this only done after the rest of probe?  Needs a comment perhaps.
> > Normally I'd expect the core probe and hence exposure of the device
> > to userspace etc to be the last thing done.
> >  
> 
> I'm doing this here for the same reason as for the spi-3wire setup. So
> if I drop the reset in the probe, the bits could be updated before it.

Put that in the function that you pass as a pointer to core_probe() - then you
can do them both at the same time and at an appropriate point.


Jonathan

^ permalink raw reply	[flat|nested] 14+ messages in thread

end of thread, other threads:[~2021-08-03 17:18 UTC | newest]

Thread overview: 14+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-07-31 20:36 [PATCH 0/2] iio: accel: Add support for ADXL313 accelerometer Lucas Stankus
2021-07-31 20:36 ` [PATCH 1/2] dt-bindings: iio: accel: Add binding documentation for ADXL313 Lucas Stankus
2021-08-01 18:04   ` Jonathan Cameron
2021-08-02 16:49     ` Lucas Stankus
2021-08-02 13:39   ` Rob Herring
2021-07-31 20:36 ` [PATCH 2/2] iio: accel: Add driver support " Lucas Stankus
2021-08-01 18:12   ` Jonathan Cameron
2021-08-02  6:57     ` Alexandru Ardelean
2021-08-02 17:28       ` Lucas Stankus
2021-08-03  7:15         ` Alexandru Ardelean
2021-08-02 17:15     ` Lucas Stankus
2021-08-03 17:18       ` Jonathan Cameron
2021-08-02  7:04   ` Alexandru Ardelean
2021-08-02 17:30     ` Lucas Stankus

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