[v2,3/6] pwm: omap-dmtimer: Fix pwm enabling sequence
diff mbox series

Message ID 20200228095651.32464-4-lokeshvutla@ti.com
State New
Headers show
Series
  • pwm: omap-dmtimer: Allow for dynamic pwm period updates
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Commit Message

Lokesh Vutla Feb. 28, 2020, 9:56 a.m. UTC
To configure DM timer in pwm mode the following needs to be set in
OMAP_TIMER_CTRL_REG using set_pwm callback:
- Set toggle mode on PORTIMERPWM output pin
- Set trigger on overflow and match on PORTIMERPWM output pin.
- Set auto reload

This is a one time configuration and needs to be set before the start of
the dm timer. But the current driver tries to set the same configuration
for every period/duty cycle update, which is not needed. So move the pwm
setup before enabling timer and do not update it in pwm_omap_dmtimer_config.

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
---
 drivers/pwm/pwm-omap-dmtimer.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

Comments

Tony Lindgren March 6, 2020, 6:04 p.m. UTC | #1
* Lokesh Vutla <lokeshvutla@ti.com> [200228 09:58]:
> To configure DM timer in pwm mode the following needs to be set in
> OMAP_TIMER_CTRL_REG using set_pwm callback:
> - Set toggle mode on PORTIMERPWM output pin
> - Set trigger on overflow and match on PORTIMERPWM output pin.
> - Set auto reload
> 
> This is a one time configuration and needs to be set before the start of
> the dm timer. But the current driver tries to set the same configuration
> for every period/duty cycle update, which is not needed. So move the pwm
> setup before enabling timer and do not update it in pwm_omap_dmtimer_config.

Still works for me:

Tested-by: Tony Lindgren <tony@atomide.com>

Patch
diff mbox series

diff --git a/drivers/pwm/pwm-omap-dmtimer.c b/drivers/pwm/pwm-omap-dmtimer.c
index a24a630ccdb9..bc338619232d 100644
--- a/drivers/pwm/pwm-omap-dmtimer.c
+++ b/drivers/pwm/pwm-omap-dmtimer.c
@@ -77,6 +77,11 @@  static int pwm_omap_dmtimer_enable(struct pwm_chip *chip,
 	struct pwm_omap_dmtimer_chip *omap = to_pwm_omap_dmtimer_chip(chip);
 
 	mutex_lock(&omap->mutex);
+	omap->pdata->set_pwm(omap->dm_timer,
+			     pwm_get_polarity(pwm) == PWM_POLARITY_INVERSED,
+			     true, OMAP_TIMER_TRIGGER_OVERFLOW_AND_COMPARE,
+			     true);
+
 	pwm_omap_dmtimer_start(omap);
 	mutex_unlock(&omap->mutex);
 
@@ -193,11 +198,6 @@  static int pwm_omap_dmtimer_config(struct pwm_chip *chip,
 	dev_dbg(chip->dev, "load value: %#08x (%d), match value: %#08x (%d)\n",
 		load_value, load_value,	match_value, match_value);
 
-	omap->pdata->set_pwm(omap->dm_timer,
-			     pwm_get_polarity(pwm) == PWM_POLARITY_INVERSED,
-			     true, OMAP_TIMER_TRIGGER_OVERFLOW_AND_COMPARE,
-			     true);
-
 	/* If config was called while timer was running it must be reenabled. */
 	if (timer_active)
 		pwm_omap_dmtimer_start(omap);