A-Team_Digital_Solutions/android_kernel_motorola_sm6375
Watch
2
0
Fork
You've already forked android_kernel_motorola_sm6375
 0
mirror of https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git synced 2026-10-29 19:21:31 -04:00
Code Issues Projects Releases Packages Wiki Activity

pwm: Set enable state properly on failed call to enable

Browse source 
The pwm_enable() function didn't clear the enabled bit if a call to the
driver's ->enable() callback returned an error. The result was that the
state of the PWM core was wrong. Clearing the bit when enable returns
an error ensures the state is properly set.

Tested-by: Jonathan Richardson <[email protected]>
Reviewed-by: Dmitry Torokhov <[email protected]>
Signed-off-by: Jonathan Richardson <[email protected]>
[[email protected]: add missing kerneldoc for the lock]
Signed-off-by: Thierry Reding <[email protected]>
This commit is contained in:
Jonathan Richardson 2015-10-16 17:40:58 -07:00 • committed by Thierry Reding
commit d1cd214277
2 changed files with 29 additions and 7 deletions
Download patch file Download diff file Expand all files Collapse all files

33
drivers/pwm/core.c
View file

@ -269,6 +269,7 @@ int pwmchip_add_with_polarity(struct pwm_chip *chip,
pwm->pwm = chip->base + i;
pwm->hwpwm = i;
pwm->polarity = polarity;
mutex_init(&pwm->lock);
radix_tree_insert(&pwm_tree, pwm->pwm, pwm);
}
@ -473,16 +474,22 @@ int pwm_set_polarity(struct pwm_device *pwm, enum pwm_polarity polarity)
if (!pwm->chip->ops->set_polarity)
return -ENOSYS;
if (pwm_is_enabled(pwm))
return -EBUSY;
mutex_lock(&pwm->lock);
if (pwm_is_enabled(pwm)) {
err = -EBUSY;
goto unlock;
}
err = pwm->chip->ops->set_polarity(pwm->chip, pwm, polarity);
if (err)
return err;
goto unlock;
pwm->polarity = polarity;
return 0;
unlock:
mutex_unlock(&pwm->lock);
return err;
}
EXPORT_SYMBOL_GPL(pwm_set_polarity);
@ -494,10 +501,22 @@ EXPORT_SYMBOL_GPL(pwm_set_polarity);
*/
int pwm_enable(struct pwm_device *pwm)
{
if (pwm && !test_and_set_bit(PWMF_ENABLED, &pwm->flags))
return pwm->chip->ops->enable(pwm->chip, pwm);
int err = 0;
return pwm ? 0 : -EINVAL;
if (!pwm)
return -EINVAL;
mutex_lock(&pwm->lock);
if (!test_and_set_bit(PWMF_ENABLED, &pwm->flags)) {
err = pwm->chip->ops->enable(pwm->chip, pwm);
if (err)
clear_bit(PWMF_ENABLED, &pwm->flags);
}
mutex_unlock(&pwm->lock);
return err;
}
EXPORT_SYMBOL_GPL(pwm_enable);