[PATCH 00/10] STM32 usart power improvements

[PATCH 00/10] STM32 usart power improvements

[Erwan Le Ray]

This series delivers power improvements for stm32-usart driver.

Bich Hemon (4):
  dt-bindings: serial: add optional pinctrl states
  serial: stm32: select pinctrl state in each suspend/resume function
  ARM: dts: stm32: Update pin states for uart4 on stm32mp157c-ed1
  ARM: dts: stm32: Update UART4 pin states on stm32mp157a-dk1

Erwan Le Ray (6):
  dt-bindings: serial: stm32: add wakeup option
  serial: stm32: add pm_runtime support
  serial: stm32: Use __maybe_unused instead of #if CONFIG_PM_SLEEP
  serial: stm32: add support for no_console_suspend
  ARM: dts: stm32: update uart4 pin configurations for low power
  ARM: dts: stm32: add wakeup capability on each usart/uart on
    stm32mp157c

 .../devicetree/bindings/serial/st,stm32-usart.txt  | 19 ++++-
 arch/arm/boot/dts/stm32mp157-pinctrl.dtsi          | 17 +++++
 arch/arm/boot/dts/stm32mp157a-dk1.dts              |  5 +-
 arch/arm/boot/dts/stm32mp157c-ed1.dts              |  5 +-
 arch/arm/boot/dts/stm32mp157c.dtsi                 | 40 ++++++++--
 drivers/tty/serial/stm32-usart.c                   | 88 ++++++++++++++++++++--
 drivers/tty/serial/stm32-usart.h                   |  1 +
 7 files changed, 155 insertions(+), 20 deletions(-)

-- 
1.9.1

[PATCH 01/10] dt-bindings: serial: stm32: add wakeup option

[Erwan Le Ray]

Add a note for enabling wakeup capabilities of usart

Signed-off-by: Bich Hemon <bich.hemon@st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@st.com>

diff --git a/Documentation/devicetree/bindings/serial/st,stm32-usart.txt b/Documentation/devicetree/bindings/serial/st,stm32-usart.txt
index 9d3efed..5ec80c1 100644
--- a/Documentation/devicetree/bindings/serial/st,stm32-usart.txt
+++ b/Documentation/devicetree/bindings/serial/st,stm32-usart.txt
@@ -19,6 +19,11 @@ Optional properties:
   linux,rs485-enabled-at-boot-time: see rs485.txt.
 - dmas: phandle(s) to DMA controller node(s). Refer to stm32-dma.txt
 - dma-names: "rx" and/or "tx"
+- wakeup-source: bool flag to indicate this device has wakeup capabilities
+- interrupt-names, if optional wake-up interrupt is used, should be:
+  - "event": the name for the interrupt line of the USART instance
+  - "wakeup" the name for the optional wake-up interrupt
+
 
 Examples:
 usart4: serial@40004c00 {
-- 
1.9.1

[PATCH 02/10] dt-bindings: serial: add optional pinctrl states

[Erwan Le Ray]

From: Bich Hemon <bich.hemon@st.com>

Add options for pinctrl states:
- "sleep" for low power
- "idle" for low power and wakeup capabilities enabled
- "no_console_suspend" for enabling console messages in low power

Signed-off-by: Bich Hemon <bich.hemon@st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@st.com>

diff --git a/Documentation/devicetree/bindings/serial/st,stm32-usart.txt b/Documentation/devicetree/bindings/serial/st,stm32-usart.txt
index 5ec80c1..64a5ea9 100644
--- a/Documentation/devicetree/bindings/serial/st,stm32-usart.txt
+++ b/Documentation/devicetree/bindings/serial/st,stm32-usart.txt
@@ -13,7 +13,14 @@ Required properties:
 - clocks: The input clock of the USART instance
 
 Optional properties:
-- pinctrl: The reference on the pins configuration
+- pinctrl-names: Set to "default". An additional "sleep" state can be defined
+  to set pins in sleep state when in low power. In case the device is used as
+  a wakeup source, "idle" state is defined in order to keep RX pin active.
+  For a console device, an optional state "no_console_suspend" can be defined
+  to enable console messages during suspend. Typically, "no_console_suspend" and
+  "default" states can refer to the same pin configuration.
+- pinctrl-n: Phandle(s) pointing to pin configuration nodes.
+  For Pinctrl properties see ../pinctrl/pinctrl-bindings.txt
 - st,hw-flow-ctrl: bool flag to enable hardware flow control.
 - rs485-rts-delay, rs485-rx-during-tx, rs485-rts-active-low,
   linux,rs485-enabled-at-boot-time: see rs485.txt.
@@ -31,8 +38,11 @@ usart4: serial@40004c00 {
 	reg = <0x40004c00 0x400>;
 	interrupts = <52>;
 	clocks = <&clk_pclk1>;
-	pinctrl-names = "default";
+	pinctrl-names = "default", "sleep", "idle", "no_console_suspend";
 	pinctrl-0 = <&pinctrl_usart4>;
+	pinctrl-1 = <&pinctrl_usart4_sleep>;
+	pinctrl-2 = <&pinctrl_usart4_idle>;
+	pinctrl-3 = <&pinctrl_usart4>;
 };
 
 usart2: serial@40004400 {
-- 
1.9.1

[PATCH 03/10] serial: stm32: select pinctrl state in each suspend/resume function

[Erwan Le Ray]

From: Bich Hemon <bich.hemon@st.com>

Select either pinctrl sleep state in suspend function or default state in
resume function.

Signed-off-by: Bich Hemon <bich.hemon@st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@st.com>

diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c
index e8d7a7b..8a7c582 100644
--- a/drivers/tty/serial/stm32-usart.c
+++ b/drivers/tty/serial/stm32-usart.c
@@ -1223,6 +1223,8 @@ static int stm32_serial_suspend(struct device *dev)
 	else
 		stm32_serial_enable_wakeup(port, false);
 
+	pinctrl_pm_select_sleep_state(dev);
+
 	return 0;
 }
 
@@ -1230,6 +1232,8 @@ static int stm32_serial_resume(struct device *dev)
 {
 	struct uart_port *port = dev_get_drvdata(dev);
 
+	pinctrl_pm_select_default_state(dev);
+
 	if (device_may_wakeup(dev))
 		stm32_serial_enable_wakeup(port, false);
 
-- 
1.9.1

[PATCH 04/10] serial: stm32: add pm_runtime support

[Erwan Le Ray]

Use pm_runtime for clock management.

Signed-off-by: Bich Hemon <bich.hemon@st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@st.com>

diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c
index 8a7c582..05d2ef6 100644
--- a/drivers/tty/serial/stm32-usart.c
+++ b/drivers/tty/serial/stm32-usart.c
@@ -765,13 +765,13 @@ static void stm32_pm(struct uart_port *port, unsigned int state,
 
 	switch (state) {
 	case UART_PM_STATE_ON:
-		clk_prepare_enable(stm32port->clk);
+		pm_runtime_get_sync(port->dev);
 		break;
 	case UART_PM_STATE_OFF:
 		spin_lock_irqsave(&port->lock, flags);
 		stm32_clr_bits(port, ofs->cr1, BIT(cfg->uart_enable_bit));
 		spin_unlock_irqrestore(&port->lock, flags);
-		clk_disable_unprepare(stm32port->clk);
+		pm_runtime_put_sync(port->dev);
 		break;
 	}
 }
@@ -1040,6 +1040,11 @@ static int stm32_serial_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, &stm32port->port);
 
+	pm_runtime_get_noresume(&pdev->dev);
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+	pm_runtime_put_sync(&pdev->dev);
+
 	return 0;
 
 err_nowup:
@@ -1058,6 +1063,9 @@ static int stm32_serial_remove(struct platform_device *pdev)
 	struct stm32_port *stm32_port = to_stm32_port(port);
 	struct stm32_usart_offsets *ofs = &stm32_port->info->ofs;
 	struct stm32_usart_config *cfg = &stm32_port->info->cfg;
+	int err;
+
+	pm_runtime_get_sync(&pdev->dev);
 
 	stm32_clr_bits(port, ofs->cr3, USART_CR3_DMAR);
 
@@ -1084,7 +1092,12 @@ static int stm32_serial_remove(struct platform_device *pdev)
 
 	clk_disable_unprepare(stm32_port->clk);
 
-	return uart_remove_one_port(&stm32_usart_driver, port);
+	err = uart_remove_one_port(&stm32_usart_driver, port);
+
+	pm_runtime_disable(&pdev->dev);
+	pm_runtime_put_noidle(&pdev->dev);
+
+	return err;
 }
 
 
@@ -1241,7 +1254,29 @@ static int stm32_serial_resume(struct device *dev)
 }
 #endif /* CONFIG_PM_SLEEP */
 
+static int __maybe_unused stm32_serial_runtime_suspend(struct device *dev)
+{
+	struct uart_port *port = dev_get_drvdata(dev);
+	struct stm32_port *stm32port = container_of(port,
+			struct stm32_port, port);
+
+	clk_disable_unprepare(stm32port->clk);
+
+	return 0;
+}
+
+static int __maybe_unused stm32_serial_runtime_resume(struct device *dev)
+{
+	struct uart_port *port = dev_get_drvdata(dev);
+	struct stm32_port *stm32port = container_of(port,
+			struct stm32_port, port);
+
+	return clk_prepare_enable(stm32port->clk);
+}
+
 static const struct dev_pm_ops stm32_serial_pm_ops = {
+	SET_RUNTIME_PM_OPS(stm32_serial_runtime_suspend,
+			   stm32_serial_runtime_resume, NULL)
 	SET_SYSTEM_SLEEP_PM_OPS(stm32_serial_suspend, stm32_serial_resume)
 };
 
-- 
1.9.1

Re: [PATCH 04/10] serial: stm32: add pm_runtime support

[Greg Kroah-Hartman]

On Tue, Jun 04, 2019 at 10:55:13AM +0200, Erwan Le Ray wrote:
> Use pm_runtime for clock management.
> 
> Signed-off-by: Bich Hemon <bich.hemon@st.com>
> Signed-off-by: Erwan Le Ray <erwan.leray@st.com>

Does not apply to my tree :(

[PATCH 05/10] serial: stm32: Use __maybe_unused instead of #if CONFIG_PM_SLEEP

[Erwan Le Ray]

Use __maybe_unused for power management related functionsinstead of
#if CONFIG_PM_SLEEP to simply the code.

fixes: 270e5a74fe4c ("serial: stm32: add wakeup mechanism")
Signed-off-by: Erwan Le Ray <erwan.leray@st.com>

diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c
index 05d2ef6..aa3da1c 100644
--- a/drivers/tty/serial/stm32-usart.c
+++ b/drivers/tty/serial/stm32-usart.c
@@ -1200,8 +1200,8 @@ static int stm32_console_setup(struct console *co, char *options)
 	.cons		= STM32_SERIAL_CONSOLE,
 };
 
-#ifdef CONFIG_PM_SLEEP
-static void stm32_serial_enable_wakeup(struct uart_port *port, bool enable)
+static void __maybe_unused stm32_serial_enable_wakeup(struct uart_port *port,
+						      bool enable)
 {
 	struct stm32_port *stm32_port = to_stm32_port(port);
 	struct stm32_usart_offsets *ofs = &stm32_port->info->ofs;
@@ -1225,7 +1225,7 @@ static void stm32_serial_enable_wakeup(struct uart_port *port, bool enable)
 	}
 }
 
-static int stm32_serial_suspend(struct device *dev)
+static int __maybe_unused stm32_serial_suspend(struct device *dev)
 {
 	struct uart_port *port = dev_get_drvdata(dev);
 
@@ -1241,7 +1241,7 @@ static int stm32_serial_suspend(struct device *dev)
 	return 0;
 }
 
-static int stm32_serial_resume(struct device *dev)
+static int __maybe_unused stm32_serial_resume(struct device *dev)
 {
 	struct uart_port *port = dev_get_drvdata(dev);
 
@@ -1252,7 +1252,6 @@ static int stm32_serial_resume(struct device *dev)
 
 	return uart_resume_port(&stm32_usart_driver, port);
 }
-#endif /* CONFIG_PM_SLEEP */
 
 static int __maybe_unused stm32_serial_runtime_suspend(struct device *dev)
 {
-- 
1.9.1

[PATCH 06/10] serial: stm32: add support for no_console_suspend

[Erwan Le Ray]

In order to display console messages in low power mode, console pins
must be kept active after suspend call.

Signed-off-by: Bich Hemon <bich.hemon@st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@st.com>

diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c
index aa3da1c..573eae1 100644
--- a/drivers/tty/serial/stm32-usart.c
+++ b/drivers/tty/serial/stm32-usart.c
@@ -24,6 +24,8 @@
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_platform.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/pinctrl/devinfo.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/pm_wakeirq.h>
@@ -802,6 +804,7 @@ static int stm32_init_port(struct stm32_port *stm32port,
 {
 	struct uart_port *port = &stm32port->port;
 	struct resource *res;
+	struct pinctrl *uart_pinctrl;
 	int ret;
 
 	port->iotype	= UPIO_MEM;
@@ -816,6 +819,24 @@ static int stm32_init_port(struct stm32_port *stm32port,
 	stm32port->wakeirq = platform_get_irq(pdev, 1);
 	stm32port->fifoen = stm32port->info->cfg.has_fifo;
 
+	uart_pinctrl = devm_pinctrl_get(&pdev->dev);
+	if (IS_ERR(uart_pinctrl)) {
+		ret = PTR_ERR(uart_pinctrl);
+		if (ret != -ENODEV) {
+			dev_err(&pdev->dev, "Can't get pinctrl, error %d\n",
+				ret);
+			return ret;
+		}
+		stm32port->console_pins = ERR_PTR(-ENODEV);
+	} else {
+		stm32port->console_pins = pinctrl_lookup_state
+			(uart_pinctrl, "no_console_suspend");
+	}
+
+	if (IS_ERR(stm32port->console_pins) && PTR_ERR(stm32port->console_pins)
+	    != -ENODEV)
+		return PTR_ERR(stm32port->console_pins);
+
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	port->membase = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(port->membase))
@@ -1228,6 +1249,7 @@ static void __maybe_unused stm32_serial_enable_wakeup(struct uart_port *port,
 static int __maybe_unused stm32_serial_suspend(struct device *dev)
 {
 	struct uart_port *port = dev_get_drvdata(dev);
+	struct stm32_port *stm32_port = to_stm32_port(port);
 
 	uart_suspend_port(&stm32_usart_driver, port);
 
@@ -1236,7 +1258,19 @@ static int __maybe_unused stm32_serial_suspend(struct device *dev)
 	else
 		stm32_serial_enable_wakeup(port, false);
 
-	pinctrl_pm_select_sleep_state(dev);
+	if (uart_console(port) && !console_suspend_enabled) {
+		if (IS_ERR(stm32_port->console_pins)) {
+			dev_err(dev, "no_console_suspend pinctrl not found\n");
+			return PTR_ERR(stm32_port->console_pins);
+		}
+
+		pinctrl_select_state(dev->pins->p, stm32_port->console_pins);
+	} else {
+		if (device_may_wakeup(dev))
+			pinctrl_pm_select_idle_state(dev);
+		else
+			pinctrl_pm_select_sleep_state(dev);
+	}
 
 	return 0;
 }
diff --git a/drivers/tty/serial/stm32-usart.h b/drivers/tty/serial/stm32-usart.h
index 6f294e2..6957d50 100644
--- a/drivers/tty/serial/stm32-usart.h
+++ b/drivers/tty/serial/stm32-usart.h
@@ -261,6 +261,7 @@ struct stm32_port {
 	bool hw_flow_control;
 	bool fifoen;
 	int wakeirq;
+	struct pinctrl_state *console_pins;
 };
 
 static struct stm32_port stm32_ports[STM32_MAX_PORTS];
-- 
1.9.1

[PATCH 07/10] ARM: dts: stm32: update uart4 pin configurations for low power

[Erwan Le Ray]

Currently, pinctrl states defines only one "sleep" configuration for pins,
no matter the possible uart low power modes (Rx pin always kept active).

Sleep pin configuration is refined for low power modes:
- "sleep" (no wakeup & console suspend enabled): put pins in analog state
  to optimize power
- "idle" (wakeup capability): keep Rx pin in alternate function
- "default" state remains untouched, to be used while the UART is active
  or in case the no_console_suspend mode is enabled

Signed-off-by: Bich Hemon <bich.hemon@st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@st.com>

diff --git a/arch/arm/boot/dts/stm32mp157-pinctrl.dtsi b/arch/arm/boot/dts/stm32mp157-pinctrl.dtsi
index 85c417d..2e1ab1b 100644
--- a/arch/arm/boot/dts/stm32mp157-pinctrl.dtsi
+++ b/arch/arm/boot/dts/stm32mp157-pinctrl.dtsi
@@ -599,6 +599,23 @@
 					bias-disable;
 				};
 			};
+
+			uart4_idle_pins_a: uart4-idle-0 {
+				pins1 {
+					pinmux = <STM32_PINMUX('G', 11, ANALOG)>; /* UART4_TX */
+				};
+				pins2 {
+					pinmux = <STM32_PINMUX('B', 2, AF8)>; /* UART4_RX */
+					bias-disable;
+				};
+			};
+
+			uart4_sleep_pins_a: uart4-sleep-0 {
+				pins {
+					pinmux = <STM32_PINMUX('G', 11, ANALOG)>, /* UART4_TX */
+						 <STM32_PINMUX('B', 2, ANALOG)>; /* UART4_RX */
+				};
+			};
 		};
 
 		pinctrl_z: pin-controller-z@54004000 {
-- 
1.9.1

[PATCH 08/10] ARM: dts: stm32: Update pin states for uart4 on stm32mp157c-ed1

[Erwan Le Ray]

From: Bich Hemon <bich.hemon@st.com>

Add idle and no_console_suspend states to uart4 pin configuration

Signed-off-by: Bich Hemon <bich.hemon@st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@st.com>

diff --git a/arch/arm/boot/dts/stm32mp157c-ed1.dts b/arch/arm/boot/dts/stm32mp157c-ed1.dts
index 62a8c78..34cc847 100644
--- a/arch/arm/boot/dts/stm32mp157c-ed1.dts
+++ b/arch/arm/boot/dts/stm32mp157c-ed1.dts
@@ -251,8 +251,11 @@
 };
 
 &uart4 {
-	pinctrl-names = "default";
+	pinctrl-names = "default", "sleep", "idle", "no_console_suspend";
 	pinctrl-0 = <&uart4_pins_a>;
+	pinctrl-1 = <&uart4_sleep_pins_a>;
+	pinctrl-2 = <&uart4_idle_pins_a>;
+	pinctrl-3 = <&uart4_pins_a>;
 	status = "okay";
 };
 
-- 
1.9.1

[PATCH 09/10] ARM: dts: stm32: Update UART4 pin states on stm32mp157a-dk1

[Erwan Le Ray]

From: Bich Hemon <bich.hemon@st.com>

Add idle and no_console_suspend states to uart4 pin configuration.

Signed-off-by: Bich Hemon <bich.hemon@st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@st.com>

diff --git a/arch/arm/boot/dts/stm32mp157a-dk1.dts b/arch/arm/boot/dts/stm32mp157a-dk1.dts
index 098dbfb..b851f80 100644
--- a/arch/arm/boot/dts/stm32mp157a-dk1.dts
+++ b/arch/arm/boot/dts/stm32mp157a-dk1.dts
@@ -244,7 +244,10 @@
 };
 
 &uart4 {
-	pinctrl-names = "default";
+	pinctrl-names = "default", "sleep", "idle", "no_console_suspend";
 	pinctrl-0 = <&uart4_pins_a>;
+	pinctrl-1 = <&uart4_sleep_pins_a>;
+	pinctrl-2 = <&uart4_idle_pins_a>;
+	pinctrl-3 = <&uart4_pins_a>;
 	status = "okay";
 };
-- 
1.9.1

[PATCH 10/10] ARM: dts: stm32: add wakeup capability on each usart/uart on stm32mp157c

[Erwan Le Ray]

- Mark all usart/uart devices as wakeup source.
- Identify all dedicated interrupts with a specific interrupt name (either
 "event" or "wakeup").
- add interrupts-extended wakeup interrupt

Signed-off-by: Erwan Le Ray <erwan.leray@st.com>

diff --git a/arch/arm/boot/dts/stm32mp157c.dtsi b/arch/arm/boot/dts/stm32mp157c.dtsi
index 2afeee6..de5b1bf 100644
--- a/arch/arm/boot/dts/stm32mp157c.dtsi
+++ b/arch/arm/boot/dts/stm32mp157c.dtsi
@@ -395,32 +395,44 @@
 		usart2: serial@4000e000 {
 			compatible = "st,stm32h7-uart";
 			reg = <0x4000e000 0x400>;
-			interrupts = <GIC_SPI 38 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "event", "wakeup";
+			interrupts-extended = <&intc GIC_SPI 38 IRQ_TYPE_LEVEL_HIGH>,
+					      <&exti 27 1>;
 			clocks = <&rcc USART2_K>;
+			wakeup-source;
 			status = "disabled";
 		};
 
 		usart3: serial@4000f000 {
 			compatible = "st,stm32h7-uart";
 			reg = <0x4000f000 0x400>;
-			interrupts = <GIC_SPI 39 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "event", "wakeup";
+			interrupts-extended = <&intc GIC_SPI 39 IRQ_TYPE_LEVEL_HIGH>,
+					      <&exti 28 1>;
 			clocks = <&rcc USART3_K>;
+			wakeup-source;
 			status = "disabled";
 		};
 
 		uart4: serial@40010000 {
 			compatible = "st,stm32h7-uart";
 			reg = <0x40010000 0x400>;
-			interrupts = <GIC_SPI 52 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "event", "wakeup";
+			interrupts-extended = <&intc GIC_SPI 52 IRQ_TYPE_LEVEL_HIGH>,
+					      <&exti 30 1>;
 			clocks = <&rcc UART4_K>;
+			wakeup-source;
 			status = "disabled";
 		};
 
 		uart5: serial@40011000 {
 			compatible = "st,stm32h7-uart";
 			reg = <0x40011000 0x400>;
-			interrupts = <GIC_SPI 53 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "event", "wakeup";
+			interrupts-extended = <&intc GIC_SPI 53 IRQ_TYPE_LEVEL_HIGH>,
+					      <&exti 31 1>;
 			clocks = <&rcc UART5_K>;
+			wakeup-source;
 			status = "disabled";
 		};
 
@@ -512,16 +524,22 @@
 		uart7: serial@40018000 {
 			compatible = "st,stm32h7-uart";
 			reg = <0x40018000 0x400>;
-			interrupts = <GIC_SPI 82 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "event", "wakeup";
+			interrupts-extended = <&intc GIC_SPI 82 IRQ_TYPE_LEVEL_HIGH>,
+					      <&exti 32 1>;
 			clocks = <&rcc UART7_K>;
+			wakeup-source;
 			status = "disabled";
 		};
 
 		uart8: serial@40019000 {
 			compatible = "st,stm32h7-uart";
 			reg = <0x40019000 0x400>;
-			interrupts = <GIC_SPI 83 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "event", "wakeup";
+			interrupts-extended = <&intc GIC_SPI 83 IRQ_TYPE_LEVEL_HIGH>,
+					      <&exti 33 1>;
 			clocks = <&rcc UART8_K>;
+			wakeup-source;
 			status = "disabled";
 		};
 
@@ -588,8 +606,11 @@
 		usart6: serial@44003000 {
 			compatible = "st,stm32h7-uart";
 			reg = <0x44003000 0x400>;
-			interrupts = <GIC_SPI 71 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "event", "wakeup";
+			interrupts-extended = <&intc GIC_SPI 71 IRQ_TYPE_LEVEL_HIGH>,
+					      <&exti 29 1>;
 			clocks = <&rcc USART6_K>;
+			wakeup-source;
 			status = "disabled";
 		};
 
@@ -1201,8 +1222,11 @@
 		usart1: serial@5c000000 {
 			compatible = "st,stm32h7-uart";
 			reg = <0x5c000000 0x400>;
-			interrupts = <GIC_SPI 37 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "event", "wakeup";
+			interrupts-extended = <&intc GIC_SPI 37 IRQ_TYPE_LEVEL_HIGH>,
+					      <&exti 26 1>;
 			clocks = <&rcc USART1_K>;
+			wakeup-source;
 			status = "disabled";
 		};
 
-- 
1.9.1

Re: [PATCH 00/10] STM32 usart power improvements

[Alexandre Torgue]

Hi Erwan,

On 6/4/19 10:55 AM, Erwan Le Ray wrote:
> This series delivers power improvements for stm32-usart driver.
> 
> Bich Hemon (4):
>    dt-bindings: serial: add optional pinctrl states
>    serial: stm32: select pinctrl state in each suspend/resume function
>    ARM: dts: stm32: Update pin states for uart4 on stm32mp157c-ed1
>    ARM: dts: stm32: Update UART4 pin states on stm32mp157a-dk1
> 
> Erwan Le Ray (6):
>    dt-bindings: serial: stm32: add wakeup option
>    serial: stm32: add pm_runtime support
>    serial: stm32: Use __maybe_unused instead of #if CONFIG_PM_SLEEP
>    serial: stm32: add support for no_console_suspend
>    ARM: dts: stm32: update uart4 pin configurations for low power
>    ARM: dts: stm32: add wakeup capability on each usart/uart on
>      stm32mp157c
> 
>   .../devicetree/bindings/serial/st,stm32-usart.txt  | 19 ++++-
>   arch/arm/boot/dts/stm32mp157-pinctrl.dtsi          | 17 +++++
>   arch/arm/boot/dts/stm32mp157a-dk1.dts              |  5 +-
>   arch/arm/boot/dts/stm32mp157c-ed1.dts              |  5 +-
>   arch/arm/boot/dts/stm32mp157c.dtsi                 | 40 ++++++++--
>   drivers/tty/serial/stm32-usart.c                   | 88 ++++++++++++++++++++--
>   drivers/tty/serial/stm32-usart.h                   |  1 +
>   7 files changed, 155 insertions(+), 20 deletions(-)
> 

I'll merge device tree part into stm32-next branch when binding part 
will be accepted.

regards
Alex