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* [PATCH 0/3] rtc: omap: Fix misc bugs
@ 2015-04-01  5:54 Lokesh Vutla
  2015-04-01  5:54 ` [PATCH 1/3] rtc: omap: Unlock and Lock rtc registers before and after register writes Lokesh Vutla
                   ` (2 more replies)
  0 siblings, 3 replies; 8+ messages in thread
From: Lokesh Vutla @ 2015-04-01  5:54 UTC (permalink / raw)
  To: a.zummo, rtc-linux
  Cc: t-kristo, nsekhar, linux-omap, linux-kernel, lokeshvutla

This patch series fixes miscellaneous bugs in OMAP RTC driver.

Tested on DRA72-evm with an out of tree patch for RTC hwmod.
Logs: http://pastebin.ubuntu.com/10716566/

Lokesh Vutla (3):
  rtc: omap: Unlock and Lock rtc registers before and after register
    writes
  rtc: omap: Update Kconfig for OMAP RTC
  rtc: omap: use module_platform_driver

 drivers/rtc/Kconfig    |  6 +++---
 drivers/rtc/rtc-omap.c | 51 ++++++++++++++++++++++++++++++++++++++++----------
 2 files changed, 44 insertions(+), 13 deletions(-)

-- 
1.9.1


^ permalink raw reply	[flat|nested] 8+ messages in thread

* [PATCH 1/3] rtc: omap: Unlock and Lock rtc registers before and after register writes
  2015-04-01  5:54 [PATCH 0/3] rtc: omap: Fix misc bugs Lokesh Vutla
@ 2015-04-01  5:54 ` Lokesh Vutla
  2015-04-01 15:52   ` [rtc-linux] " Alexandre Belloni
  2015-04-01  5:54 ` [PATCH 2/3] rtc: omap: Update Kconfig for OMAP RTC Lokesh Vutla
  2015-04-01  5:54 ` [PATCH 3/3] rtc: omap: use module_platform_driver Lokesh Vutla
  2 siblings, 1 reply; 8+ messages in thread
From: Lokesh Vutla @ 2015-04-01  5:54 UTC (permalink / raw)
  To: a.zummo, rtc-linux
  Cc: t-kristo, nsekhar, linux-omap, linux-kernel, lokeshvutla

RTC module contains a kicker mechanism to prevent any spurious writes
from changing the register values. This mechanism requires two MMR
writes to the KICK0 and KICK1 registers with exact data values
before the kicker lock mechanism is released.

Currently the driver release the lock in the probe and leaves it enabled
until the rtc driver removal. This eliminates the idea of preventing
spurious writes when RTC driver is loaded.
So implement rtc lock and unlock functions before and after register writes.

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
---
- This is as advised by Paul to implement lock and unlock functions in
  the driver and not to unlock and leave it in probe.
  The same discussion can be seen here:
  http://www.mail-archive.com/linux-omap%40vger.kernel.org/msg111588.html

 drivers/rtc/rtc-omap.c | 46 ++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 38 insertions(+), 8 deletions(-)

diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
index 8e5851a..96cc613 100644
--- a/drivers/rtc/rtc-omap.c
+++ b/drivers/rtc/rtc-omap.c
@@ -156,6 +156,22 @@ static inline void rtc_writel(struct omap_rtc *rtc, unsigned int reg, u32 val)
 	writel(val, rtc->base + reg);
 }
 
+static void rtc_unlock(struct omap_rtc *rtc)
+{
+	if (rtc->type->has_kicker) {
+		rtc_writel(rtc, OMAP_RTC_KICK0_REG, KICK0_VALUE);
+		rtc_writel(rtc, OMAP_RTC_KICK1_REG, KICK1_VALUE);
+	}
+}
+
+static void rtc_lock(struct omap_rtc *rtc)
+{
+	if (rtc->type->has_kicker) {
+		rtc_writel(rtc, OMAP_RTC_KICK0_REG, 0);
+		rtc_writel(rtc, OMAP_RTC_KICK1_REG, 0);
+	}
+}
+
 /*
  * We rely on the rtc framework to handle locking (rtc->ops_lock),
  * so the only other requirement is that register accesses which
@@ -186,7 +202,9 @@ static irqreturn_t rtc_irq(int irq, void *dev_id)
 
 	/* alarm irq? */
 	if (irq_data & OMAP_RTC_STATUS_ALARM) {
+		rtc_unlock(rtc);
 		rtc_write(rtc, OMAP_RTC_STATUS_REG, OMAP_RTC_STATUS_ALARM);
+		rtc_lock(rtc);
 		events |= RTC_IRQF | RTC_AF;
 	}
 
@@ -218,9 +236,11 @@ static int omap_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
 		irqwake_reg &= ~OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
 	}
 	rtc_wait_not_busy(rtc);
+	rtc_unlock(rtc);
 	rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, reg);
 	if (rtc->type->has_irqwakeen)
 		rtc_write(rtc, OMAP_RTC_IRQWAKEEN, irqwake_reg);
+	rtc_lock(rtc);
 	local_irq_enable();
 
 	return 0;
@@ -293,12 +313,14 @@ static int omap_rtc_set_time(struct device *dev, struct rtc_time *tm)
 	local_irq_disable();
 	rtc_wait_not_busy(rtc);
 
+	rtc_unlock(rtc);
 	rtc_write(rtc, OMAP_RTC_YEARS_REG, tm->tm_year);
 	rtc_write(rtc, OMAP_RTC_MONTHS_REG, tm->tm_mon);
 	rtc_write(rtc, OMAP_RTC_DAYS_REG, tm->tm_mday);
 	rtc_write(rtc, OMAP_RTC_HOURS_REG, tm->tm_hour);
 	rtc_write(rtc, OMAP_RTC_MINUTES_REG, tm->tm_min);
 	rtc_write(rtc, OMAP_RTC_SECONDS_REG, tm->tm_sec);
+	rtc_lock(rtc);
 
 	local_irq_enable();
 
@@ -341,6 +363,7 @@ static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
 	local_irq_disable();
 	rtc_wait_not_busy(rtc);
 
+	rtc_unlock(rtc);
 	rtc_write(rtc, OMAP_RTC_ALARM_YEARS_REG, alm->time.tm_year);
 	rtc_write(rtc, OMAP_RTC_ALARM_MONTHS_REG, alm->time.tm_mon);
 	rtc_write(rtc, OMAP_RTC_ALARM_DAYS_REG, alm->time.tm_mday);
@@ -362,6 +385,7 @@ static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
 	rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, reg);
 	if (rtc->type->has_irqwakeen)
 		rtc_write(rtc, OMAP_RTC_IRQWAKEEN, irqwake_reg);
+	rtc_lock(rtc);
 
 	local_irq_enable();
 
@@ -391,6 +415,7 @@ static void omap_rtc_power_off(void)
 	unsigned long now;
 	u32 val;
 
+	rtc_unlock(rtc);
 	/* enable pmic_power_en control */
 	val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
 	rtc_writel(rtc, OMAP_RTC_PMIC_REG, val | OMAP_RTC_PMIC_POWER_EN_EN);
@@ -423,6 +448,7 @@ static void omap_rtc_power_off(void)
 	val = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
 	rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG,
 			val | OMAP_RTC_INTERRUPTS_IT_ALARM2);
+	rtc_lock(rtc);
 
 	/*
 	 * Wait for alarm to trigger (within two seconds) and external PMIC to
@@ -527,10 +553,7 @@ static int __init omap_rtc_probe(struct platform_device *pdev)
 	pm_runtime_enable(&pdev->dev);
 	pm_runtime_get_sync(&pdev->dev);
 
-	if (rtc->type->has_kicker) {
-		rtc_writel(rtc, OMAP_RTC_KICK0_REG, KICK0_VALUE);
-		rtc_writel(rtc, OMAP_RTC_KICK1_REG, KICK1_VALUE);
-	}
+	rtc_unlock(rtc);
 
 	/*
 	 * disable interrupts
@@ -593,6 +616,8 @@ static int __init omap_rtc_probe(struct platform_device *pdev)
 	if (reg != new_ctrl)
 		rtc_write(rtc, OMAP_RTC_CTRL_REG, new_ctrl);
 
+	rtc_lock(rtc);
+
 	device_init_wakeup(&pdev->dev, true);
 
 	rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
@@ -626,8 +651,7 @@ static int __init omap_rtc_probe(struct platform_device *pdev)
 
 err:
 	device_init_wakeup(&pdev->dev, false);
-	if (rtc->type->has_kicker)
-		rtc_writel(rtc, OMAP_RTC_KICK0_REG, 0);
+	rtc_lock(rtc);
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 
@@ -646,11 +670,11 @@ static int __exit omap_rtc_remove(struct platform_device *pdev)
 
 	device_init_wakeup(&pdev->dev, 0);
 
+	rtc_unlock(rtc);
 	/* leave rtc running, but disable irqs */
 	rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
 
-	if (rtc->type->has_kicker)
-		rtc_writel(rtc, OMAP_RTC_KICK0_REG, 0);
+	rtc_lock(rtc);
 
 	/* Disable the clock/module */
 	pm_runtime_put_sync(&pdev->dev);
@@ -666,6 +690,7 @@ static int omap_rtc_suspend(struct device *dev)
 
 	rtc->interrupts_reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
 
+	rtc_unlock(rtc);
 	/*
 	 * FIXME: the RTC alarm is not currently acting as a wakeup event
 	 * source on some platforms, and in fact this enable() call is just
@@ -675,6 +700,7 @@ static int omap_rtc_suspend(struct device *dev)
 		enable_irq_wake(rtc->irq_alarm);
 	else
 		rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
+	rtc_lock(rtc);
 
 	/* Disable the clock/module */
 	pm_runtime_put_sync(dev);
@@ -689,10 +715,12 @@ static int omap_rtc_resume(struct device *dev)
 	/* Enable the clock/module so that we can access the registers */
 	pm_runtime_get_sync(dev);
 
+	rtc_unlock(rtc);
 	if (device_may_wakeup(dev))
 		disable_irq_wake(rtc->irq_alarm);
 	else
 		rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, rtc->interrupts_reg);
+	rtc_lock(rtc);
 
 	return 0;
 }
@@ -709,9 +737,11 @@ static void omap_rtc_shutdown(struct platform_device *pdev)
 	 * Keep the ALARM interrupt enabled to allow the system to power up on
 	 * alarm events.
 	 */
+	rtc_unlock(rtc);
 	mask = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
 	mask &= OMAP_RTC_INTERRUPTS_IT_ALARM;
 	rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, mask);
+	rtc_lock(rtc);
 }
 
 static struct platform_driver omap_rtc_driver = {
-- 
1.9.1


^ permalink raw reply	[flat|nested] 8+ messages in thread

* [PATCH 2/3] rtc: omap: Update Kconfig for OMAP RTC
  2015-04-01  5:54 [PATCH 0/3] rtc: omap: Fix misc bugs Lokesh Vutla
  2015-04-01  5:54 ` [PATCH 1/3] rtc: omap: Unlock and Lock rtc registers before and after register writes Lokesh Vutla
@ 2015-04-01  5:54 ` Lokesh Vutla
  2015-04-01 15:52   ` [rtc-linux] " Alexandre Belloni
  2015-04-01  5:54 ` [PATCH 3/3] rtc: omap: use module_platform_driver Lokesh Vutla
  2 siblings, 1 reply; 8+ messages in thread
From: Lokesh Vutla @ 2015-04-01  5:54 UTC (permalink / raw)
  To: a.zummo, rtc-linux
  Cc: t-kristo, nsekhar, linux-omap, linux-kernel, lokeshvutla

RTC is present in AM43xx and DRA7xx also. Updating the Kconfig
to depend on ARCH_OMAP or ARCH_DAVINCI

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
---
 drivers/rtc/Kconfig | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index b5b5c3d..40faf56 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -1121,11 +1121,11 @@ config RTC_DRV_IMXDI
 	   will be called "rtc-imxdi".
 
 config RTC_DRV_OMAP
-	tristate "TI OMAP1"
-	depends on ARCH_OMAP15XX || ARCH_OMAP16XX || ARCH_OMAP730 || ARCH_DAVINCI_DA8XX || SOC_AM33XX
+	tristate "TI OMAP Real Time Clock"
+	depends on ARCH_OMAP || ARCH_DAVINCI
 	help
 	  Say "yes" here to support the on chip real time clock
-	  present on TI OMAP1, AM33xx and DA8xx/OMAP-L13x.
+	  present on TI OMAP1, AM33xx, DA8xx/OMAP-L13x, AM43xx and DRA7xx.
 
 	  This driver can also be built as a module, if so, module
 	  will be called rtc-omap.
-- 
1.9.1


^ permalink raw reply	[flat|nested] 8+ messages in thread

* [PATCH 3/3] rtc: omap: use module_platform_driver
  2015-04-01  5:54 [PATCH 0/3] rtc: omap: Fix misc bugs Lokesh Vutla
  2015-04-01  5:54 ` [PATCH 1/3] rtc: omap: Unlock and Lock rtc registers before and after register writes Lokesh Vutla
  2015-04-01  5:54 ` [PATCH 2/3] rtc: omap: Update Kconfig for OMAP RTC Lokesh Vutla
@ 2015-04-01  5:54 ` Lokesh Vutla
  2015-04-01 15:53   ` [rtc-linux] " Alexandre Belloni
  2 siblings, 1 reply; 8+ messages in thread
From: Lokesh Vutla @ 2015-04-01  5:54 UTC (permalink / raw)
  To: a.zummo, rtc-linux
  Cc: t-kristo, nsekhar, linux-omap, linux-kernel, lokeshvutla

module_platform_driver_probe() prevents driver from requesting probe deferral.
So using module_platform_drive() to support probe deferral.

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
---
 drivers/rtc/rtc-omap.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
index 96cc613..a4965a0 100644
--- a/drivers/rtc/rtc-omap.c
+++ b/drivers/rtc/rtc-omap.c
@@ -510,7 +510,7 @@ static const struct of_device_id omap_rtc_of_match[] = {
 };
 MODULE_DEVICE_TABLE(of, omap_rtc_of_match);
 
-static int __init omap_rtc_probe(struct platform_device *pdev)
+static int omap_rtc_probe(struct platform_device *pdev)
 {
 	struct omap_rtc	*rtc;
 	struct resource	*res;
@@ -745,6 +745,7 @@ static void omap_rtc_shutdown(struct platform_device *pdev)
 }
 
 static struct platform_driver omap_rtc_driver = {
+	.probe		= omap_rtc_probe,
 	.remove		= __exit_p(omap_rtc_remove),
 	.shutdown	= omap_rtc_shutdown,
 	.driver		= {
@@ -755,7 +756,7 @@ static struct platform_driver omap_rtc_driver = {
 	.id_table	= omap_rtc_id_table,
 };
 
-module_platform_driver_probe(omap_rtc_driver, omap_rtc_probe);
+module_platform_driver(omap_rtc_driver);
 
 MODULE_ALIAS("platform:omap_rtc");
 MODULE_AUTHOR("George G. Davis (and others)");
-- 
1.9.1


^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [rtc-linux] [PATCH 1/3] rtc: omap: Unlock and Lock rtc registers before and after register writes
  2015-04-01  5:54 ` [PATCH 1/3] rtc: omap: Unlock and Lock rtc registers before and after register writes Lokesh Vutla
@ 2015-04-01 15:52   ` Alexandre Belloni
  2015-04-02 11:12     ` Lokesh Vutla
  0 siblings, 1 reply; 8+ messages in thread
From: Alexandre Belloni @ 2015-04-01 15:52 UTC (permalink / raw)
  To: rtc-linux
  Cc: a.zummo, t-kristo, nsekhar, linux-omap, linux-kernel, lokeshvutla

Hi,

On 01/04/2015 at 11:24:56 +0530, Lokesh Vutla wrote :
> RTC module contains a kicker mechanism to prevent any spurious writes
> from changing the register values. This mechanism requires two MMR
> writes to the KICK0 and KICK1 registers with exact data values
> before the kicker lock mechanism is released.
> 
> Currently the driver release the lock in the probe and leaves it enabled
> until the rtc driver removal. This eliminates the idea of preventing
> spurious writes when RTC driver is loaded.
> So implement rtc lock and unlock functions before and after register writes.
> 
> Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
> ---
> - This is as advised by Paul to implement lock and unlock functions in
>   the driver and not to unlock and leave it in probe.
>   The same discussion can be seen here:
>   http://www.mail-archive.com/linux-omap%40vger.kernel.org/msg111588.html
> 
>  drivers/rtc/rtc-omap.c | 46 ++++++++++++++++++++++++++++++++++++++--------
>  1 file changed, 38 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
> index 8e5851a..96cc613 100644
> --- a/drivers/rtc/rtc-omap.c
> +++ b/drivers/rtc/rtc-omap.c
> @@ -156,6 +156,22 @@ static inline void rtc_writel(struct omap_rtc *rtc, unsigned int reg, u32 val)
>  	writel(val, rtc->base + reg);
>  }
>  
> +static void rtc_unlock(struct omap_rtc *rtc)
> +{
> +	if (rtc->type->has_kicker) {

Instead of testing for has_kicker each time, I would add .lock and
.unlock to omap_rtc_device_type and directly use rtc->type->lock and
rtc->type->unlock.

> +		rtc_writel(rtc, OMAP_RTC_KICK0_REG, KICK0_VALUE);
> +		rtc_writel(rtc, OMAP_RTC_KICK1_REG, KICK1_VALUE);
> +	}
> +}
> +
-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [rtc-linux] [PATCH 2/3] rtc: omap: Update Kconfig for OMAP RTC
  2015-04-01  5:54 ` [PATCH 2/3] rtc: omap: Update Kconfig for OMAP RTC Lokesh Vutla
@ 2015-04-01 15:52   ` Alexandre Belloni
  0 siblings, 0 replies; 8+ messages in thread
From: Alexandre Belloni @ 2015-04-01 15:52 UTC (permalink / raw)
  To: rtc-linux
  Cc: a.zummo, t-kristo, nsekhar, linux-omap, linux-kernel, lokeshvutla

On 01/04/2015 at 11:24:57 +0530, Lokesh Vutla wrote :
> RTC is present in AM43xx and DRA7xx also. Updating the Kconfig
> to depend on ARCH_OMAP or ARCH_DAVINCI
> 
> Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

> ---
>  drivers/rtc/Kconfig | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
> index b5b5c3d..40faf56 100644
> --- a/drivers/rtc/Kconfig
> +++ b/drivers/rtc/Kconfig
> @@ -1121,11 +1121,11 @@ config RTC_DRV_IMXDI
>  	   will be called "rtc-imxdi".
>  
>  config RTC_DRV_OMAP
> -	tristate "TI OMAP1"
> -	depends on ARCH_OMAP15XX || ARCH_OMAP16XX || ARCH_OMAP730 || ARCH_DAVINCI_DA8XX || SOC_AM33XX
> +	tristate "TI OMAP Real Time Clock"
> +	depends on ARCH_OMAP || ARCH_DAVINCI
>  	help
>  	  Say "yes" here to support the on chip real time clock
> -	  present on TI OMAP1, AM33xx and DA8xx/OMAP-L13x.
> +	  present on TI OMAP1, AM33xx, DA8xx/OMAP-L13x, AM43xx and DRA7xx.
>  
>  	  This driver can also be built as a module, if so, module
>  	  will be called rtc-omap.
> -- 
> 1.9.1
> 
> -- 
> -- 
> You received this message because you are subscribed to "rtc-linux".
> Membership options at http://groups.google.com/group/rtc-linux .
> Please read http://groups.google.com/group/rtc-linux/web/checklist
> before submitting a driver.
> --- 
> You received this message because you are subscribed to the Google Groups "rtc-linux" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to rtc-linux+unsubscribe@googlegroups.com.
> For more options, visit https://groups.google.com/d/optout.

-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [rtc-linux] [PATCH 3/3] rtc: omap: use module_platform_driver
  2015-04-01  5:54 ` [PATCH 3/3] rtc: omap: use module_platform_driver Lokesh Vutla
@ 2015-04-01 15:53   ` Alexandre Belloni
  0 siblings, 0 replies; 8+ messages in thread
From: Alexandre Belloni @ 2015-04-01 15:53 UTC (permalink / raw)
  To: rtc-linux
  Cc: a.zummo, t-kristo, nsekhar, linux-omap, linux-kernel, lokeshvutla

On 01/04/2015 at 11:24:58 +0530, Lokesh Vutla wrote :
> module_platform_driver_probe() prevents driver from requesting probe deferral.
> So using module_platform_drive() to support probe deferral.
> 
> Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

> ---
>  drivers/rtc/rtc-omap.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
> index 96cc613..a4965a0 100644
> --- a/drivers/rtc/rtc-omap.c
> +++ b/drivers/rtc/rtc-omap.c
> @@ -510,7 +510,7 @@ static const struct of_device_id omap_rtc_of_match[] = {
>  };
>  MODULE_DEVICE_TABLE(of, omap_rtc_of_match);
>  
> -static int __init omap_rtc_probe(struct platform_device *pdev)
> +static int omap_rtc_probe(struct platform_device *pdev)
>  {
>  	struct omap_rtc	*rtc;
>  	struct resource	*res;
> @@ -745,6 +745,7 @@ static void omap_rtc_shutdown(struct platform_device *pdev)
>  }
>  
>  static struct platform_driver omap_rtc_driver = {
> +	.probe		= omap_rtc_probe,
>  	.remove		= __exit_p(omap_rtc_remove),
>  	.shutdown	= omap_rtc_shutdown,
>  	.driver		= {
> @@ -755,7 +756,7 @@ static struct platform_driver omap_rtc_driver = {
>  	.id_table	= omap_rtc_id_table,
>  };
>  
> -module_platform_driver_probe(omap_rtc_driver, omap_rtc_probe);
> +module_platform_driver(omap_rtc_driver);
>  
>  MODULE_ALIAS("platform:omap_rtc");
>  MODULE_AUTHOR("George G. Davis (and others)");
> -- 
> 1.9.1
> 
> -- 
> -- 
> You received this message because you are subscribed to "rtc-linux".
> Membership options at http://groups.google.com/group/rtc-linux .
> Please read http://groups.google.com/group/rtc-linux/web/checklist
> before submitting a driver.
> --- 
> You received this message because you are subscribed to the Google Groups "rtc-linux" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to rtc-linux+unsubscribe@googlegroups.com.
> For more options, visit https://groups.google.com/d/optout.

-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [rtc-linux] [PATCH 1/3] rtc: omap: Unlock and Lock rtc registers before and after register writes
  2015-04-01 15:52   ` [rtc-linux] " Alexandre Belloni
@ 2015-04-02 11:12     ` Lokesh Vutla
  0 siblings, 0 replies; 8+ messages in thread
From: Lokesh Vutla @ 2015-04-02 11:12 UTC (permalink / raw)
  To: Alexandre Belloni, rtc-linux
  Cc: a.zummo, t-kristo, nsekhar, linux-omap, linux-kernel

Hi,

On Wednesday 01 April 2015 09:22 PM, Alexandre Belloni wrote:
> Hi,
> 
> On 01/04/2015 at 11:24:56 +0530, Lokesh Vutla wrote :
>> RTC module contains a kicker mechanism to prevent any spurious writes
>> from changing the register values. This mechanism requires two MMR
>> writes to the KICK0 and KICK1 registers with exact data values
>> before the kicker lock mechanism is released.
>>
>> Currently the driver release the lock in the probe and leaves it enabled
>> until the rtc driver removal. This eliminates the idea of preventing
>> spurious writes when RTC driver is loaded.
>> So implement rtc lock and unlock functions before and after register writes.
>>
>> Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
>> ---
>> - This is as advised by Paul to implement lock and unlock functions in
>>   the driver and not to unlock and leave it in probe.
>>   The same discussion can be seen here:
>>   http://www.mail-archive.com/linux-omap%40vger.kernel.org/msg111588.html
>>
>>  drivers/rtc/rtc-omap.c | 46 ++++++++++++++++++++++++++++++++++++++--------
>>  1 file changed, 38 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
>> index 8e5851a..96cc613 100644
>> --- a/drivers/rtc/rtc-omap.c
>> +++ b/drivers/rtc/rtc-omap.c
>> @@ -156,6 +156,22 @@ static inline void rtc_writel(struct omap_rtc *rtc, unsigned int reg, u32 val)
>>  	writel(val, rtc->base + reg);
>>  }
>>  
>> +static void rtc_unlock(struct omap_rtc *rtc)
>> +{
>> +	if (rtc->type->has_kicker) {
> 
> Instead of testing for has_kicker each time, I would add .lock and
> .unlock to omap_rtc_device_type and directly use rtc->type->lock and
> rtc->type->unlock.
Makes sense. I have posted v2 of my series updating this.

Thanks and regards,
Lokesh
> 
>> +		rtc_writel(rtc, OMAP_RTC_KICK0_REG, KICK0_VALUE);
>> +		rtc_writel(rtc, OMAP_RTC_KICK1_REG, KICK1_VALUE);
>> +	}
>> +}
>> +


^ permalink raw reply	[flat|nested] 8+ messages in thread

end of thread, other threads:[~2015-04-02 11:13 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2015-04-01  5:54 [PATCH 0/3] rtc: omap: Fix misc bugs Lokesh Vutla
2015-04-01  5:54 ` [PATCH 1/3] rtc: omap: Unlock and Lock rtc registers before and after register writes Lokesh Vutla
2015-04-01 15:52   ` [rtc-linux] " Alexandre Belloni
2015-04-02 11:12     ` Lokesh Vutla
2015-04-01  5:54 ` [PATCH 2/3] rtc: omap: Update Kconfig for OMAP RTC Lokesh Vutla
2015-04-01 15:52   ` [rtc-linux] " Alexandre Belloni
2015-04-01  5:54 ` [PATCH 3/3] rtc: omap: use module_platform_driver Lokesh Vutla
2015-04-01 15:53   ` [rtc-linux] " Alexandre Belloni

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