diff options
Diffstat (limited to 'drivers/pwm/core.c')
| -rw-r--r-- | drivers/pwm/core.c | 82 |
1 files changed, 81 insertions, 1 deletions
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c index c6e05078d3ad..f5acdaa52707 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -371,7 +371,7 @@ EXPORT_SYMBOL_GPL(pwm_free); */ int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns) { - if (!pwm || period_ns == 0 || duty_ns > period_ns) + if (!pwm || duty_ns < 0 || period_ns <= 0 || duty_ns > period_ns) return -EINVAL; return pwm->chip->ops->config(pwm->chip, pwm, duty_ns, period_ns); @@ -379,6 +379,28 @@ int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns) EXPORT_SYMBOL_GPL(pwm_config); /** + * pwm_set_polarity() - configure the polarity of a PWM signal + * @pwm: PWM device + * @polarity: new polarity of the PWM signal + * + * Note that the polarity cannot be configured while the PWM device is enabled + */ +int pwm_set_polarity(struct pwm_device *pwm, enum pwm_polarity polarity) +{ + if (!pwm || !pwm->chip->ops) + return -EINVAL; + + if (!pwm->chip->ops->set_polarity) + return -ENOSYS; + + if (test_bit(PWMF_ENABLED, &pwm->flags)) + return -EBUSY; + + return pwm->chip->ops->set_polarity(pwm->chip, pwm, polarity); +} +EXPORT_SYMBOL_GPL(pwm_set_polarity); + +/** * pwm_enable() - start a PWM output toggling * @pwm: PWM device */ @@ -624,6 +646,64 @@ out: } EXPORT_SYMBOL_GPL(pwm_put); +static void devm_pwm_release(struct device *dev, void *res) +{ + pwm_put(*(struct pwm_device **)res); +} + +/** + * devm_pwm_get() - resource managed pwm_get() + * @dev: device for PWM consumer + * @con_id: consumer name + * + * This function performs like pwm_get() but the acquired PWM device will + * automatically be released on driver detach. + */ +struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id) +{ + struct pwm_device **ptr, *pwm; + + ptr = devres_alloc(devm_pwm_release, sizeof(**ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + pwm = pwm_get(dev, con_id); + if (!IS_ERR(pwm)) { + *ptr = pwm; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return pwm; +} +EXPORT_SYMBOL_GPL(devm_pwm_get); + +static int devm_pwm_match(struct device *dev, void *res, void *data) +{ + struct pwm_device **p = res; + + if (WARN_ON(!p || !*p)) + return 0; + + return *p == data; +} + +/** + * devm_pwm_put() - resource managed pwm_put() + * @dev: device for PWM consumer + * @pwm: PWM device + * + * Release a PWM previously allocated using devm_pwm_get(). Calling this + * function is usually not needed because devm-allocated resources are + * automatically released on driver detach. + */ +void devm_pwm_put(struct device *dev, struct pwm_device *pwm) +{ + WARN_ON(devres_release(dev, devm_pwm_release, devm_pwm_match, pwm)); +} +EXPORT_SYMBOL_GPL(devm_pwm_put); + #ifdef CONFIG_DEBUG_FS static void pwm_dbg_show(struct pwm_chip *chip, struct seq_file *s) { |