diff options
author | Brian Norris <computersforpeace@gmail.com> | 2015-11-15 20:30:53 -0800 |
---|---|---|
committer | Brian Norris <computersforpeace@gmail.com> | 2015-11-15 20:31:29 -0800 |
commit | 617f41836c17688141e1c66f4156c2084f8ca86d (patch) | |
tree | e57d631bb3bb061a0ff2e99bc85f94bd1c30598f /drivers/pwm/core.c | |
parent | 26add94cd535d1e000e7871fe69c7bb89e942d67 (diff) | |
parent | 8005c49d9aea74d382f474ce11afbbc7d7130bec (diff) |
Merge v4.4-rc1 into MTD development
Sync up with the upstream development.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Diffstat (limited to 'drivers/pwm/core.c')
-rw-r--r-- | drivers/pwm/core.c | 37 |
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) |