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authorDaniel Vetter <daniel.vetter@ffwll.ch>2015-11-23 09:04:05 +0100
committerDaniel Vetter <daniel.vetter@ffwll.ch>2015-11-23 09:04:05 +0100
commit92907cbbef8625bb3998d1eb385fc88f23c97a3f (patch)
tree15626ff9287e37c3cb81c7286d6db5a7fd77c854 /drivers/pwm/core.c
parent15fbfccfe92c62ae8d1ecc647c44157ed01ac02e (diff)
parent1ec218373b8ebda821aec00bb156a9c94fad9cd4 (diff)
Merge tag 'v4.4-rc2' into drm-intel-next-queued
Linux 4.4-rc2 Backmerge to get at commit 1b0e3a049efe471c399674fd954500ce97438d30 Author: Imre Deak <imre.deak@intel.com> Date: Thu Nov 5 23:04:11 2015 +0200 drm/i915/skl: disable display side power well support for now so that we can proplery re-eanble skl power wells in -next. Conflicts are just adjacent lines changed, except for intel_fbdev.c where we need to interleave the changs. Nothing nefarious. Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Diffstat (limited to 'drivers/pwm/core.c')
-rw-r--r--drivers/pwm/core.c37
1 files changed, 29 insertions, 8 deletions
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index 3f9df3ea3350..d24ca5f281b4 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -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);
@@ -719,8 +738,10 @@ struct pwm_device *pwm_get(struct device *dev, const char *con_id)
}
}
- if (!chosen)
+ if (!chosen) {
+ pwm = ERR_PTR(-ENODEV);
goto out;
+ }
chip = pwmchip_find_by_name(chosen->provider);
if (!chip)