Commit 01b571fb authored by Uwe Kleine-König's avatar Uwe Kleine-König Committed by Thierry Reding
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pwm: omap-dmtimer: Drop locking 



The pwm driver only provides a single PWM line, so there are no concurrent
calls of the callbacks from different consumers. A single consumer is
expected not to do concurrent calls into the pwm framework. So there is
nothing to serialize and the lock can go away.

Signed-off-by: default avatarUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: default avatarThierry Reding <thierry.reding@gmail.com>
parent 46cfec2a

drivers/pwm/pwm-omap-dmtimer.c

+4 −16
Original line number Diff line number Diff line
@@ -37,7 +37,6 @@ 
#include <linux/err.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/mutex.h>

#include <linux/of.h>

#include <linux/of_platform.h>

#include <clocksource/timer-ti-dm.h>
@@ -55,7 +54,6 @@ 
 * struct pwm_omap_dmtimer_chip - Structure representing a pwm chip

 *				  corresponding to omap dmtimer.

 * @chip:		PWM chip structure representing PWM controller

 * @mutex:		Mutex to protect pwm apply state

 * @dm_timer:		Pointer to omap dm timer.

 * @pdata:		Pointer to omap dm timer ops.

 * @dm_timer_pdev:	Pointer to omap dm timer platform device
@@ -63,7 +61,6 @@ 
struct pwm_omap_dmtimer_chip {

	struct pwm_chip chip;

	/* Mutex to protect pwm apply state */

	struct mutex mutex;

	struct omap_dm_timer *dm_timer;

	const struct omap_dm_timer_ops *pdata;

	struct platform_device *dm_timer_pdev;
@@ -277,13 +274,11 @@ static int pwm_omap_dmtimer_apply(struct pwm_chip *chip, 
				  const struct pwm_state *state)

{

	struct pwm_omap_dmtimer_chip *omap = to_pwm_omap_dmtimer_chip(chip);

	int ret = 0;



	mutex_lock(&omap->mutex);

	int ret;



	if (pwm_omap_dmtimer_is_enabled(omap) && !state->enabled) {

		omap->pdata->stop(omap->dm_timer);

		goto unlock_mutex;

		return 0;

	}



	if (pwm_omap_dmtimer_polarity(omap) != state->polarity)
@@ -292,7 +287,7 @@ static int pwm_omap_dmtimer_apply(struct pwm_chip *chip, 
	ret = pwm_omap_dmtimer_config(chip, pwm, state->duty_cycle,

				      state->period);

	if (ret)

		goto unlock_mutex;

		return ret;



	if (!pwm_omap_dmtimer_is_enabled(omap) && state->enabled) {

		omap->pdata->set_pwm(omap->dm_timer,
@@ -303,10 +298,7 @@ static int pwm_omap_dmtimer_apply(struct pwm_chip *chip, 
		pwm_omap_dmtimer_start(omap);

	}



unlock_mutex:

	mutex_unlock(&omap->mutex);



	return ret;

	return 0;

}



static const struct pwm_ops pwm_omap_dmtimer_ops = {
@@ -404,8 +396,6 @@ static int pwm_omap_dmtimer_probe(struct platform_device *pdev) 
	omap->chip.ops = &pwm_omap_dmtimer_ops;

	omap->chip.npwm = 1;



	mutex_init(&omap->mutex);



	ret = pwmchip_add(&omap->chip);

	if (ret < 0) {

		dev_err(&pdev->dev, "failed to register PWM\n");
@@ -452,8 +442,6 @@ static void pwm_omap_dmtimer_remove(struct platform_device *pdev) 
	omap->pdata->free(omap->dm_timer);



	put_device(&omap->dm_timer_pdev->dev);



	mutex_destroy(&omap->mutex);

}



static const struct of_device_id pwm_omap_dmtimer_of_match[] = {