[v2] clocksource: timer-ti-dm : Capture functionality for OMAP DM timer

[PATCH v2] clocksource: timer-ti-dm : Capture functionality for OMAP DM timer

Posted by Gokul Praveen 1 month, 3 weeks ago

Add PWM capture function in DM timer driver.

OMAP DM timer hardware supports capture feature.It can be used to
timestamp events (falling/rising edges) detected on input signal.

Signed-off-by: Gokul Praveen <g-praveen@ti.com>
---
v2<==> v1
===========
* Optimized the code and fixed some comment spacing and newline issues

Precondition : Before calling driver API,it is assumed that the
               capture signal is active else both duty cycle
               and period returned by driver will not be valid.
---
 drivers/clocksource/timer-ti-dm.c          | 119 ++++++++++++++++++++-
 include/linux/platform_data/dmtimer-omap.h |   4 +
 2 files changed, 121 insertions(+), 2 deletions(-)

diff --git a/drivers/clocksource/timer-ti-dm.c b/drivers/clocksource/timer-ti-dm.c
index e9e32df6b566..793e7cdcb1b1 100644
--- a/drivers/clocksource/timer-ti-dm.c
+++ b/drivers/clocksource/timer-ti-dm.c
@@ -31,6 +31,7 @@
 #include <linux/platform_data/dmtimer-omap.h>
 
 #include <clocksource/timer-ti-dm.h>
+#include <linux/delay.h>
 
 /*
  * timer errata flags
@@ -836,6 +837,48 @@ static int omap_dm_timer_set_match(struct omap_dm_timer *cookie, int enable,
 	return 0;
 }
 
+static int omap_dm_timer_set_cap(struct omap_dm_timer *cookie,
+					int autoreload, bool config_period)
+{
+	struct dmtimer *timer;
+	struct device *dev;
+	int rc;
+	u32 l;
+
+	timer = to_dmtimer(cookie);
+	if (unlikely(!timer))
+		return -EINVAL;
+
+	dev = &timer->pdev->dev;
+	rc = pm_runtime_resume_and_get(dev);
+	if (rc)
+		return rc;
+	/*
+	 *  1. Select autoreload mode. TIMER_TCLR[1] AR bit.
+	 *  2. TIMER_TCLR[14]: Sets the functionality of the TIMER IO pin.
+	 *  3. TIMER_TCLR[13] : Capture mode select bit.
+	 *  3. TIMER_TCLR[9-8] : Select transition capture mode.
+	 */
+
+	l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
+
+	if (autoreload)
+		l |= OMAP_TIMER_CTRL_AR;
+
+	l |= OMAP_TIMER_CTRL_CAPTMODE | OMAP_TIMER_CTRL_GPOCFG;
+
+	if (config_period == true)
+		l |= OMAP_TIMER_CTRL_TCM_LOWTOHIGH; /* Time Period config */
+	else
+		l |= OMAP_TIMER_CTRL_TCM_BOTHEDGES; /* Duty Cycle config */
+
+	dmtimer_write(timer, OMAP_TIMER_CTRL_REG, l);
+
+	pm_runtime_put_sync(dev);
+
+	return 0;
+}
+
 static int omap_dm_timer_set_pwm(struct omap_dm_timer *cookie, int def_on,
 				 int toggle, int trigger, int autoreload)
 {
@@ -1023,23 +1066,92 @@ static unsigned int omap_dm_timer_read_counter(struct omap_dm_timer *cookie)
 	return __omap_dm_timer_read_counter(timer);
 }
 
+static inline unsigned int __omap_dm_timer_cap(struct dmtimer *timer, int idx)
+{
+	return idx == 0 ? dmtimer_read(timer, OMAP_TIMER_CAPTURE_REG) :
+			  dmtimer_read(timer, OMAP_TIMER_CAPTURE2_REG);
+}
+
 static int omap_dm_timer_write_counter(struct omap_dm_timer *cookie, unsigned int value)
 {
 	struct dmtimer *timer;
+	struct device *dev;
 
 	timer = to_dmtimer(cookie);
-	if (unlikely(!timer || !atomic_read(&timer->enabled))) {
-		pr_err("%s: timer not available or enabled.\n", __func__);
+	if (unlikely(!timer)) {
+		pr_err("%s: timer not available.\n", __func__);
 		return -EINVAL;
 	}
 
+	dev = &timer->pdev->dev;
+
+	pm_runtime_resume_and_get(dev);
 	dmtimer_write(timer, OMAP_TIMER_COUNTER_REG, value);
+	pm_runtime_put_sync(dev);
 
 	/* Save the context */
 	timer->context.tcrr = value;
 	return 0;
 }
 
+/**
+ * omap_dm_timer_cap_counter() - Calculate the high count or period count depending on the
+ * configuration.
+ * @cookie:Pointer to OMAP DM timer
+ * @is_period:Whether to configure timer in period or duty cycle mode
+ *
+ * Return high count or period count if timer is enabled else appropriate error.
+ */
+static unsigned int omap_dm_timer_cap_counter(struct omap_dm_timer *cookie,	bool is_period)
+{
+	struct dmtimer *timer;
+	unsigned int cap1 = 0;
+	unsigned int cap2 = 0;
+	u32 l, ret;
+
+	timer = to_dmtimer(cookie);
+	if (unlikely(!timer || !atomic_read(&timer->enabled))) {
+		pr_err("%s:timer is not available or enabled.%p\n", __func__, (void *)timer);
+		return -EINVAL;
+	}
+
+	/* Stop the timer */
+	omap_dm_timer_stop(cookie);
+
+	/* Clear the timer counter value to 0 */
+	ret = omap_dm_timer_write_counter(cookie, 0);
+	if (ret)
+		return ret;
+
+	/* Sets the timer capture configuration for period/duty cycle calculation */
+	ret = omap_dm_timer_set_cap(cookie, true, is_period);
+	if (ret) {
+		pr_err("%s: Failed to set timer capture configuration.\n", __func__);
+		return ret;
+	}
+	/* Start the timer */
+	omap_dm_timer_start(cookie);
+
+	/*
+	 * 1 sec delay is given so as to provide
+	 * enough time to capture low frequency signals.
+	 */
+	msleep(1000);
+
+	cap1 = __omap_dm_timer_cap(timer, 0);
+	cap2 = __omap_dm_timer_cap(timer, 1);
+
+	/*
+	 *  Clears the TCLR configuration.
+	 *  The start bit must be set to 1 as the timer is already in start mode.
+	 */
+	l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
+	l &= ~(0xffff) | 0x1;
+	dmtimer_write(timer, OMAP_TIMER_CTRL_REG, l);
+
+	return (cap2-cap1);
+}
+
 static int __maybe_unused omap_dm_timer_runtime_suspend(struct device *dev)
 {
 	struct dmtimer *timer = dev_get_drvdata(dev);
@@ -1246,6 +1358,9 @@ static const struct omap_dm_timer_ops dmtimer_ops = {
 	.write_counter = omap_dm_timer_write_counter,
 	.read_status = omap_dm_timer_read_status,
 	.write_status = omap_dm_timer_write_status,
+	.set_cap = omap_dm_timer_set_cap,
+	.get_cap_status = omap_dm_timer_get_pwm_status,
+	.read_cap = omap_dm_timer_cap_counter,
 };
 
 static const struct dmtimer_platform_data omap3plus_pdata = {
diff --git a/include/linux/platform_data/dmtimer-omap.h b/include/linux/platform_data/dmtimer-omap.h
index 95d852aef130..726d89143842 100644
--- a/include/linux/platform_data/dmtimer-omap.h
+++ b/include/linux/platform_data/dmtimer-omap.h
@@ -36,9 +36,13 @@ struct omap_dm_timer_ops {
 	int	(*set_pwm)(struct omap_dm_timer *timer, int def_on,
 			   int toggle, int trigger, int autoreload);
 	int	(*get_pwm_status)(struct omap_dm_timer *timer);
+	int	(*set_cap)(struct omap_dm_timer *timer,
+			   int autoreload, bool config_period);
+	int	(*get_cap_status)(struct omap_dm_timer *timer);
 	int	(*set_prescaler)(struct omap_dm_timer *timer, int prescaler);
 
 	unsigned int (*read_counter)(struct omap_dm_timer *timer);
+	unsigned int (*read_cap)(struct omap_dm_timer *timer, bool is_period);
 	int	(*write_counter)(struct omap_dm_timer *timer,
 				 unsigned int value);
 	unsigned int (*read_status)(struct omap_dm_timer *timer);
-- 
2.34.1

Re: [PATCH v2] clocksource: timer-ti-dm : Capture functionality for OMAP DM timer

Posted by Daniel Lezcano 3 weeks, 5 days ago

On 12/08/2025 12:53, Gokul Praveen wrote:
> Add PWM capture function in DM timer driver.
> 
> OMAP DM timer hardware supports capture feature.It can be used to
> timestamp events (falling/rising edges) detected on input signal.
> 
> Signed-off-by: Gokul Praveen <g-praveen@ti.com>

Applied, thanks

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Re: [PATCH v2] clocksource: timer-ti-dm : Capture functionality for OMAP DM timer

Posted by Neha Malcom Francis 1 month, 2 weeks ago

Hi Gokul

On 12/08/25 16:23, Gokul Praveen wrote:
> Add PWM capture function in DM timer driver.
> 
> OMAP DM timer hardware supports capture feature.It can be used to
> timestamp events (falling/rising edges) detected on input signal.
> 
> Signed-off-by: Gokul Praveen <g-praveen@ti.com>
> ---
> v2<==> v1
> ===========
> * Optimized the code and fixed some comment spacing and newline issues
> 
> Precondition : Before calling driver API,it is assumed that the
>                capture signal is active else both duty cycle
>                and period returned by driver will not be valid.
> ---
>  drivers/clocksource/timer-ti-dm.c          | 119 ++++++++++++++++++++-
>  include/linux/platform_data/dmtimer-omap.h |   4 +
>  2 files changed, 121 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/clocksource/timer-ti-dm.c b/drivers/clocksource/timer-ti-dm.c
> index e9e32df6b566..793e7cdcb1b1 100644
> --- a/drivers/clocksource/timer-ti-dm.c
> +++ b/drivers/clocksource/timer-ti-dm.c
> @@ -31,6 +31,7 @@
>  #include <linux/platform_data/dmtimer-omap.h>
>  
>  #include <clocksource/timer-ti-dm.h>
> +#include <linux/delay.h>
>  
>  /*
>   * timer errata flags
> @@ -836,6 +837,48 @@ static int omap_dm_timer_set_match(struct omap_dm_timer *cookie, int enable,
>  	return 0;
>  }
>  
> +static int omap_dm_timer_set_cap(struct omap_dm_timer *cookie,
> +					int autoreload, bool config_period)
> +{
> +	struct dmtimer *timer;
> +	struct device *dev;
> +	int rc;
> +	u32 l;
> +
> +	timer = to_dmtimer(cookie);
> +	if (unlikely(!timer))
> +		return -EINVAL;
> +
> +	dev = &timer->pdev->dev;
> +	rc = pm_runtime_resume_and_get(dev);
> +	if (rc)
> +		return rc;
> +	/*
> +	 *  1. Select autoreload mode. TIMER_TCLR[1] AR bit.
> +	 *  2. TIMER_TCLR[14]: Sets the functionality of the TIMER IO pin.
> +	 *  3. TIMER_TCLR[13] : Capture mode select bit.
> +	 *  3. TIMER_TCLR[9-8] : Select transition capture mode.
> +	 */
> +
> +	l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
> +
> +	if (autoreload)
> +		l |= OMAP_TIMER_CTRL_AR;
> +
> +	l |= OMAP_TIMER_CTRL_CAPTMODE | OMAP_TIMER_CTRL_GPOCFG;
> +
> +	if (config_period == true)
> +		l |= OMAP_TIMER_CTRL_TCM_LOWTOHIGH; /* Time Period config */
> +	else
> +		l |= OMAP_TIMER_CTRL_TCM_BOTHEDGES; /* Duty Cycle config */
> +
> +	dmtimer_write(timer, OMAP_TIMER_CTRL_REG, l);
> +
> +	pm_runtime_put_sync(dev);
> +
> +	return 0;
> +}
> +
>  static int omap_dm_timer_set_pwm(struct omap_dm_timer *cookie, int def_on,
>  				 int toggle, int trigger, int autoreload)
>  {
> @@ -1023,23 +1066,92 @@ static unsigned int omap_dm_timer_read_counter(struct omap_dm_timer *cookie)
>  	return __omap_dm_timer_read_counter(timer);
>  }
>  
> +static inline unsigned int __omap_dm_timer_cap(struct dmtimer *timer, int idx)
> +{
> +	return idx == 0 ? dmtimer_read(timer, OMAP_TIMER_CAPTURE_REG) :
> +			  dmtimer_read(timer, OMAP_TIMER_CAPTURE2_REG);
> +}
> +
>  static int omap_dm_timer_write_counter(struct omap_dm_timer *cookie, unsigned int value)
>  {
>  	struct dmtimer *timer;
> +	struct device *dev;
>  
>  	timer = to_dmtimer(cookie);
> -	if (unlikely(!timer || !atomic_read(&timer->enabled))) {
> -		pr_err("%s: timer not available or enabled.\n", __func__);
> +	if (unlikely(!timer)) {
> +		pr_err("%s: timer not available.\n", __func__);
>  		return -EINVAL;
>  	}
>  
> +	dev = &timer->pdev->dev;
> +
> +	pm_runtime_resume_and_get(dev);
>  	dmtimer_write(timer, OMAP_TIMER_COUNTER_REG, value);
> +	pm_runtime_put_sync(dev);
>  
>  	/* Save the context */
>  	timer->context.tcrr = value;
>  	return 0;
>  }
>  
> +/**
> + * omap_dm_timer_cap_counter() - Calculate the high count or period count depending on the
> + * configuration.
> + * @cookie:Pointer to OMAP DM timer
> + * @is_period:Whether to configure timer in period or duty cycle mode
> + *
> + * Return high count or period count if timer is enabled else appropriate error.
> + */
> +static unsigned int omap_dm_timer_cap_counter(struct omap_dm_timer *cookie,	bool is_period)
> +{
> +	struct dmtimer *timer;
> +	unsigned int cap1 = 0;
> +	unsigned int cap2 = 0;
> +	u32 l, ret;
> +
> +	timer = to_dmtimer(cookie);
> +	if (unlikely(!timer || !atomic_read(&timer->enabled))) {
> +		pr_err("%s:timer is not available or enabled.%p\n", __func__, (void *)timer);
> +		return -EINVAL;
> +	}
> +
> +	/* Stop the timer */
> +	omap_dm_timer_stop(cookie);
> +
> +	/* Clear the timer counter value to 0 */
> +	ret = omap_dm_timer_write_counter(cookie, 0);
> +	if (ret)
> +		return ret;
> +
> +	/* Sets the timer capture configuration for period/duty cycle calculation */
> +	ret = omap_dm_timer_set_cap(cookie, true, is_period);
> +	if (ret) {
> +		pr_err("%s: Failed to set timer capture configuration.\n", __func__);
> +		return ret;
> +	}
> +	/* Start the timer */
> +	omap_dm_timer_start(cookie);
> +
> +	/*
> +	 * 1 sec delay is given so as to provide
> +	 * enough time to capture low frequency signals.
> +	 */
> +	msleep(1000);
> +
> +	cap1 = __omap_dm_timer_cap(timer, 0);
> +	cap2 = __omap_dm_timer_cap(timer, 1);
> +
> +	/*
> +	 *  Clears the TCLR configuration.
> +	 *  The start bit must be set to 1 as the timer is already in start mode.
> +	 */
> +	l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
> +	l &= ~(0xffff) | 0x1;
> +	dmtimer_write(timer, OMAP_TIMER_CTRL_REG, l);
> +
> +	return (cap2-cap1);
> +}
> +
>  static int __maybe_unused omap_dm_timer_runtime_suspend(struct device *dev)
>  {
>  	struct dmtimer *timer = dev_get_drvdata(dev);
> @@ -1246,6 +1358,9 @@ static const struct omap_dm_timer_ops dmtimer_ops = {
>  	.write_counter = omap_dm_timer_write_counter,
>  	.read_status = omap_dm_timer_read_status,
>  	.write_status = omap_dm_timer_write_status,
> +	.set_cap = omap_dm_timer_set_cap,
> +	.get_cap_status = omap_dm_timer_get_pwm_status,
> +	.read_cap = omap_dm_timer_cap_counter,
>  };
>  
>  static const struct dmtimer_platform_data omap3plus_pdata = {
> diff --git a/include/linux/platform_data/dmtimer-omap.h b/include/linux/platform_data/dmtimer-omap.h
> index 95d852aef130..726d89143842 100644
> --- a/include/linux/platform_data/dmtimer-omap.h
> +++ b/include/linux/platform_data/dmtimer-omap.h
> @@ -36,9 +36,13 @@ struct omap_dm_timer_ops {
>  	int	(*set_pwm)(struct omap_dm_timer *timer, int def_on,
>  			   int toggle, int trigger, int autoreload);
>  	int	(*get_pwm_status)(struct omap_dm_timer *timer);
> +	int	(*set_cap)(struct omap_dm_timer *timer,
> +			   int autoreload, bool config_period);
> +	int	(*get_cap_status)(struct omap_dm_timer *timer);
>  	int	(*set_prescaler)(struct omap_dm_timer *timer, int prescaler);
>  
>  	unsigned int (*read_counter)(struct omap_dm_timer *timer);
> +	unsigned int (*read_cap)(struct omap_dm_timer *timer, bool is_period);
>  	int	(*write_counter)(struct omap_dm_timer *timer,
>  				 unsigned int value);
>  	unsigned int (*read_status)(struct omap_dm_timer *timer);

LGTM

Reviewed-by: Neha Malcom Francis <n-francis@ti.com>

-- 
Thanking You
Neha Malcom Francis

Re: [PATCH v2] clocksource: timer-ti-dm : Capture functionality for OMAP DM timer

Posted by Gokul Praveen 1 month, 1 week ago

Hi Daniel,

Is this patch good to be merged?

Regards
Gokul

On 21/08/25 19:13, Neha Malcom Francis wrote:
> Hi Gokul
> 
> On 12/08/25 16:23, Gokul Praveen wrote:
>> Add PWM capture function in DM timer driver.
>>
>> OMAP DM timer hardware supports capture feature.It can be used to
>> timestamp events (falling/rising edges) detected on input signal.
>>
>> Signed-off-by: Gokul Praveen <g-praveen@ti.com>
>> ---
>> v2<==> v1
>> ===========
>> * Optimized the code and fixed some comment spacing and newline issues
>>
>> Precondition : Before calling driver API,it is assumed that the
>>                 capture signal is active else both duty cycle
>>                 and period returned by driver will not be valid.
>> ---
>>   drivers/clocksource/timer-ti-dm.c          | 119 ++++++++++++++++++++-
>>   include/linux/platform_data/dmtimer-omap.h |   4 +
>>   2 files changed, 121 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/clocksource/timer-ti-dm.c b/drivers/clocksource/timer-ti-dm.c
>> index e9e32df6b566..793e7cdcb1b1 100644
>> --- a/drivers/clocksource/timer-ti-dm.c
>> +++ b/drivers/clocksource/timer-ti-dm.c
>> @@ -31,6 +31,7 @@
>>   #include <linux/platform_data/dmtimer-omap.h>
>>   
>>   #include <clocksource/timer-ti-dm.h>
>> +#include <linux/delay.h>
>>   
>>   /*
>>    * timer errata flags
>> @@ -836,6 +837,48 @@ static int omap_dm_timer_set_match(struct omap_dm_timer *cookie, int enable,
>>   	return 0;
>>   }
>>   
>> +static int omap_dm_timer_set_cap(struct omap_dm_timer *cookie,
>> +					int autoreload, bool config_period)
>> +{
>> +	struct dmtimer *timer;
>> +	struct device *dev;
>> +	int rc;
>> +	u32 l;
>> +
>> +	timer = to_dmtimer(cookie);
>> +	if (unlikely(!timer))
>> +		return -EINVAL;
>> +
>> +	dev = &timer->pdev->dev;
>> +	rc = pm_runtime_resume_and_get(dev);
>> +	if (rc)
>> +		return rc;
>> +	/*
>> +	 *  1. Select autoreload mode. TIMER_TCLR[1] AR bit.
>> +	 *  2. TIMER_TCLR[14]: Sets the functionality of the TIMER IO pin.
>> +	 *  3. TIMER_TCLR[13] : Capture mode select bit.
>> +	 *  3. TIMER_TCLR[9-8] : Select transition capture mode.
>> +	 */
>> +
>> +	l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
>> +
>> +	if (autoreload)
>> +		l |= OMAP_TIMER_CTRL_AR;
>> +
>> +	l |= OMAP_TIMER_CTRL_CAPTMODE | OMAP_TIMER_CTRL_GPOCFG;
>> +
>> +	if (config_period == true)
>> +		l |= OMAP_TIMER_CTRL_TCM_LOWTOHIGH; /* Time Period config */
>> +	else
>> +		l |= OMAP_TIMER_CTRL_TCM_BOTHEDGES; /* Duty Cycle config */
>> +
>> +	dmtimer_write(timer, OMAP_TIMER_CTRL_REG, l);
>> +
>> +	pm_runtime_put_sync(dev);
>> +
>> +	return 0;
>> +}
>> +
>>   static int omap_dm_timer_set_pwm(struct omap_dm_timer *cookie, int def_on,
>>   				 int toggle, int trigger, int autoreload)
>>   {
>> @@ -1023,23 +1066,92 @@ static unsigned int omap_dm_timer_read_counter(struct omap_dm_timer *cookie)
>>   	return __omap_dm_timer_read_counter(timer);
>>   }
>>   
>> +static inline unsigned int __omap_dm_timer_cap(struct dmtimer *timer, int idx)
>> +{
>> +	return idx == 0 ? dmtimer_read(timer, OMAP_TIMER_CAPTURE_REG) :
>> +			  dmtimer_read(timer, OMAP_TIMER_CAPTURE2_REG);
>> +}
>> +
>>   static int omap_dm_timer_write_counter(struct omap_dm_timer *cookie, unsigned int value)
>>   {
>>   	struct dmtimer *timer;
>> +	struct device *dev;
>>   
>>   	timer = to_dmtimer(cookie);
>> -	if (unlikely(!timer || !atomic_read(&timer->enabled))) {
>> -		pr_err("%s: timer not available or enabled.\n", __func__);
>> +	if (unlikely(!timer)) {
>> +		pr_err("%s: timer not available.\n", __func__);
>>   		return -EINVAL;
>>   	}
>>   
>> +	dev = &timer->pdev->dev;
>> +
>> +	pm_runtime_resume_and_get(dev);
>>   	dmtimer_write(timer, OMAP_TIMER_COUNTER_REG, value);
>> +	pm_runtime_put_sync(dev);
>>   
>>   	/* Save the context */
>>   	timer->context.tcrr = value;
>>   	return 0;
>>   }
>>   
>> +/**
>> + * omap_dm_timer_cap_counter() - Calculate the high count or period count depending on the
>> + * configuration.
>> + * @cookie:Pointer to OMAP DM timer
>> + * @is_period:Whether to configure timer in period or duty cycle mode
>> + *
>> + * Return high count or period count if timer is enabled else appropriate error.
>> + */
>> +static unsigned int omap_dm_timer_cap_counter(struct omap_dm_timer *cookie,	bool is_period)
>> +{
>> +	struct dmtimer *timer;
>> +	unsigned int cap1 = 0;
>> +	unsigned int cap2 = 0;
>> +	u32 l, ret;
>> +
>> +	timer = to_dmtimer(cookie);
>> +	if (unlikely(!timer || !atomic_read(&timer->enabled))) {
>> +		pr_err("%s:timer is not available or enabled.%p\n", __func__, (void *)timer);
>> +		return -EINVAL;
>> +	}
>> +
>> +	/* Stop the timer */
>> +	omap_dm_timer_stop(cookie);
>> +
>> +	/* Clear the timer counter value to 0 */
>> +	ret = omap_dm_timer_write_counter(cookie, 0);
>> +	if (ret)
>> +		return ret;
>> +
>> +	/* Sets the timer capture configuration for period/duty cycle calculation */
>> +	ret = omap_dm_timer_set_cap(cookie, true, is_period);
>> +	if (ret) {
>> +		pr_err("%s: Failed to set timer capture configuration.\n", __func__);
>> +		return ret;
>> +	}
>> +	/* Start the timer */
>> +	omap_dm_timer_start(cookie);
>> +
>> +	/*
>> +	 * 1 sec delay is given so as to provide
>> +	 * enough time to capture low frequency signals.
>> +	 */
>> +	msleep(1000);
>> +
>> +	cap1 = __omap_dm_timer_cap(timer, 0);
>> +	cap2 = __omap_dm_timer_cap(timer, 1);
>> +
>> +	/*
>> +	 *  Clears the TCLR configuration.
>> +	 *  The start bit must be set to 1 as the timer is already in start mode.
>> +	 */
>> +	l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
>> +	l &= ~(0xffff) | 0x1;
>> +	dmtimer_write(timer, OMAP_TIMER_CTRL_REG, l);
>> +
>> +	return (cap2-cap1);
>> +}
>> +
>>   static int __maybe_unused omap_dm_timer_runtime_suspend(struct device *dev)
>>   {
>>   	struct dmtimer *timer = dev_get_drvdata(dev);
>> @@ -1246,6 +1358,9 @@ static const struct omap_dm_timer_ops dmtimer_ops = {
>>   	.write_counter = omap_dm_timer_write_counter,
>>   	.read_status = omap_dm_timer_read_status,
>>   	.write_status = omap_dm_timer_write_status,
>> +	.set_cap = omap_dm_timer_set_cap,
>> +	.get_cap_status = omap_dm_timer_get_pwm_status,
>> +	.read_cap = omap_dm_timer_cap_counter,
>>   };
>>   
>>   static const struct dmtimer_platform_data omap3plus_pdata = {
>> diff --git a/include/linux/platform_data/dmtimer-omap.h b/include/linux/platform_data/dmtimer-omap.h
>> index 95d852aef130..726d89143842 100644
>> --- a/include/linux/platform_data/dmtimer-omap.h
>> +++ b/include/linux/platform_data/dmtimer-omap.h
>> @@ -36,9 +36,13 @@ struct omap_dm_timer_ops {
>>   	int	(*set_pwm)(struct omap_dm_timer *timer, int def_on,
>>   			   int toggle, int trigger, int autoreload);
>>   	int	(*get_pwm_status)(struct omap_dm_timer *timer);
>> +	int	(*set_cap)(struct omap_dm_timer *timer,
>> +			   int autoreload, bool config_period);
>> +	int	(*get_cap_status)(struct omap_dm_timer *timer);
>>   	int	(*set_prescaler)(struct omap_dm_timer *timer, int prescaler);
>>   
>>   	unsigned int (*read_counter)(struct omap_dm_timer *timer);
>> +	unsigned int (*read_cap)(struct omap_dm_timer *timer, bool is_period);
>>   	int	(*write_counter)(struct omap_dm_timer *timer,
>>   				 unsigned int value);
>>   	unsigned int (*read_status)(struct omap_dm_timer *timer);
> 
> LGTM
> 
> Reviewed-by: Neha Malcom Francis <n-francis@ti.com>
>