diff options
| -rw-r--r-- | drivers/pwm/core.c | 44 | ||||
| -rw-r--r-- | include/linux/pwm.h | 14 |
2 files changed, 52 insertions, 6 deletions
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c index 257cbcdd3ec3..3f9df3ea3350 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -200,6 +200,8 @@ static void of_pwmchip_remove(struct pwm_chip *chip) * pwm_set_chip_data() - set private chip data for a PWM * @pwm: PWM device * @data: pointer to chip-specific data + * + * Returns: 0 on success or a negative error code on failure. */ int pwm_set_chip_data(struct pwm_device *pwm, void *data) { @@ -215,6 +217,8 @@ EXPORT_SYMBOL_GPL(pwm_set_chip_data); /** * pwm_get_chip_data() - get private chip data for a PWM * @pwm: PWM device + * + * Returns: A pointer to the chip-private data for the PWM device. */ void *pwm_get_chip_data(struct pwm_device *pwm) { @@ -230,6 +234,8 @@ EXPORT_SYMBOL_GPL(pwm_get_chip_data); * Register a new PWM chip. If chip->base < 0 then a dynamically assigned base * will be used. The initial polarity for all channels is specified by the * @polarity parameter. + * + * Returns: 0 on success or a negative error code on failure. */ int pwmchip_add_with_polarity(struct pwm_chip *chip, enum pwm_polarity polarity) @@ -291,6 +297,8 @@ EXPORT_SYMBOL_GPL(pwmchip_add_with_polarity); * * Register a new PWM chip. If chip->base < 0 then a dynamically assigned base * will be used. The initial polarity for all channels is normal. + * + * Returns: 0 on success or a negative error code on failure. */ int pwmchip_add(struct pwm_chip *chip) { @@ -304,6 +312,8 @@ EXPORT_SYMBOL_GPL(pwmchip_add); * * Removes a PWM chip. This function may return busy if the PWM chip provides * a PWM device that is still requested. + * + * Returns: 0 on success or a negative error code on failure. */ int pwmchip_remove(struct pwm_chip *chip) { @@ -338,10 +348,13 @@ EXPORT_SYMBOL_GPL(pwmchip_remove); /** * pwm_request() - request a PWM device - * @pwm_id: global PWM device index + * @pwm: global PWM device index * @label: PWM device label * * This function is deprecated, use pwm_get() instead. + * + * Returns: A pointer to a PWM device or an ERR_PTR()-encoded error code on + * failure. */ struct pwm_device *pwm_request(int pwm, const char *label) { @@ -376,9 +389,9 @@ EXPORT_SYMBOL_GPL(pwm_request); * @index: per-chip index of the PWM to request * @label: a literal description string of this PWM * - * Returns the PWM at the given index of the given PWM chip. A negative error - * code is returned if the index is not valid for the specified PWM chip or - * if the PWM device cannot be requested. + * Returns: A pointer to the PWM device at the given index of the given PWM + * chip. A negative error code is returned if the index is not valid for the + * specified PWM chip or if the PWM device cannot be requested. */ struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, unsigned int index, @@ -419,6 +432,8 @@ EXPORT_SYMBOL_GPL(pwm_free); * @pwm: PWM device * @duty_ns: "on" time (in nanoseconds) * @period_ns: duration (in nanoseconds) of one cycle + * + * Returns: 0 on success or a negative error code on failure. */ int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns) { @@ -443,7 +458,10 @@ EXPORT_SYMBOL_GPL(pwm_config); * @pwm: PWM device * @polarity: new polarity of the PWM signal * - * Note that the polarity cannot be configured while the PWM device is enabled + * Note that the polarity cannot be configured while the PWM device is + * enabled. + * + * Returns: 0 on success or a negative error code on failure. */ int pwm_set_polarity(struct pwm_device *pwm, enum pwm_polarity polarity) { @@ -471,6 +489,8 @@ EXPORT_SYMBOL_GPL(pwm_set_polarity); /** * pwm_enable() - start a PWM output toggling * @pwm: PWM device + * + * Returns: 0 on success or a negative error code on failure. */ int pwm_enable(struct pwm_device *pwm) { @@ -524,6 +544,9 @@ static struct pwm_chip *of_node_to_pwmchip(struct device_node *np) * lookup of the PWM index. This also means that the "pwm-names" property * becomes mandatory for devices that look up the PWM device via the con_id * parameter. + * + * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded + * error code on failure. */ struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id) { @@ -630,6 +653,9 @@ void pwm_remove_table(struct pwm_lookup *table, size_t num) * * Once a PWM chip has been found the specified PWM device will be requested * and is ready to be used. + * + * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded + * error code on failure. */ struct pwm_device *pwm_get(struct device *dev, const char *con_id) { @@ -752,6 +778,9 @@ static void devm_pwm_release(struct device *dev, void *res) * * This function performs like pwm_get() but the acquired PWM device will * automatically be released on driver detach. + * + * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded + * error code on failure. */ struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id) { @@ -781,6 +810,9 @@ EXPORT_SYMBOL_GPL(devm_pwm_get); * * This function performs like of_pwm_get() but the acquired PWM device will * automatically be released on driver detach. + * + * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded + * error code on failure. */ struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np, const char *con_id) @@ -832,7 +864,7 @@ EXPORT_SYMBOL_GPL(devm_pwm_put); * pwm_can_sleep() - report whether PWM access will sleep * @pwm: PWM device * - * It returns true if accessing the PWM can sleep, false otherwise. + * Returns: True if accessing the PWM can sleep, false otherwise. */ bool pwm_can_sleep(struct pwm_device *pwm) { diff --git a/include/linux/pwm.h b/include/linux/pwm.h index 7c4b6f35241d..d681f6875aef 100644 --- a/include/linux/pwm.h +++ b/include/linux/pwm.h @@ -79,6 +79,18 @@ enum { PWMF_EXPORTED = 1 << 2, }; +/** + * struct pwm_device - PWM channel object + * @label: name of the PWM device + * @flags: flags associated with the PWM device + * @hwpwm: per-chip relative index of the PWM device + * @pwm: global index of the PWM device + * @chip: PWM chip providing this PWM device + * @chip_data: chip-private data associated with the PWM device + * @period: period of the PWM signal (in nanoseconds) + * @duty_cycle: duty cycle of the PWM signal (in nanoseconds) + * @polarity: polarity of the PWM signal + */ struct pwm_device { const char *label; unsigned long flags; @@ -163,6 +175,8 @@ struct pwm_ops { * @base: number of first PWM controlled by this chip * @npwm: number of PWMs controlled by this chip * @pwms: array of PWM devices allocated by the framework + * @of_xlate: request a PWM device given a device tree PWM specifier + * @of_pwm_n_cells: number of cells expected in the device tree PWM specifier * @can_sleep: must be true if the .config(), .enable() or .disable() * operations may sleep */ |