diff options
| -rw-r--r-- | drivers/pwm/core.c | 27 | ||||
| -rw-r--r-- | include/linux/pwm.h | 24 |
2 files changed, 51 insertions, 0 deletions
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c index dba3843c53b8..8f40604046d6 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -525,6 +525,33 @@ int pwm_apply_state(struct pwm_device *pwm, struct pwm_state *state) EXPORT_SYMBOL_GPL(pwm_apply_state); /** + * pwm_capture() - capture and report a PWM signal + * @pwm: PWM device + * @result: structure to fill with capture result + * @timeout: time to wait, in milliseconds, before giving up on capture + * + * Returns: 0 on success or a negative error code on failure. + */ +int pwm_capture(struct pwm_device *pwm, struct pwm_capture *result, + unsigned long timeout) +{ + int err; + + if (!pwm || !pwm->chip->ops) + return -EINVAL; + + if (!pwm->chip->ops->capture) + return -ENOSYS; + + mutex_lock(&pwm_lock); + err = pwm->chip->ops->capture(pwm->chip, pwm, result, timeout); + mutex_unlock(&pwm_lock); + + return err; +} +EXPORT_SYMBOL_GPL(pwm_capture); + +/** * pwm_adjust_config() - adjust the current PWM config to the PWM arguments * @pwm: PWM device * diff --git a/include/linux/pwm.h b/include/linux/pwm.h index 17018f3c066e..8402b5dd3e06 100644 --- a/include/linux/pwm.h +++ b/include/linux/pwm.h @@ -5,7 +5,9 @@ #include <linux/mutex.h> #include <linux/of.h> +struct pwm_capture; struct seq_file; + struct pwm_chip; /** @@ -153,6 +155,7 @@ static inline void pwm_get_args(const struct pwm_device *pwm, * @free: optional hook for freeing a PWM * @config: configure duty cycles and period length for this PWM * @set_polarity: configure the polarity of this PWM + * @capture: capture and report PWM signal * @enable: enable PWM output toggling * @disable: disable PWM output toggling * @apply: atomically apply a new PWM config. The state argument @@ -172,6 +175,8 @@ struct pwm_ops { int duty_ns, int period_ns); int (*set_polarity)(struct pwm_chip *chip, struct pwm_device *pwm, enum pwm_polarity polarity); + int (*capture)(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_capture *result, unsigned long timeout); int (*enable)(struct pwm_chip *chip, struct pwm_device *pwm); void (*disable)(struct pwm_chip *chip, struct pwm_device *pwm); int (*apply)(struct pwm_chip *chip, struct pwm_device *pwm, @@ -212,6 +217,16 @@ struct pwm_chip { bool can_sleep; }; +/** + * struct pwm_capture - PWM capture data + * @period: period of the PWM signal (in nanoseconds) + * @duty_cycle: duty cycle of the PWM signal (in nanoseconds) + */ +struct pwm_capture { + unsigned int period; + unsigned int duty_cycle; +}; + #if IS_ENABLED(CONFIG_PWM) /* PWM user APIs */ struct pwm_device *pwm_request(int pwm_id, const char *label); @@ -322,6 +337,8 @@ static inline void pwm_disable(struct pwm_device *pwm) /* PWM provider APIs */ +int pwm_capture(struct pwm_device *pwm, struct pwm_capture *result, + unsigned long timeout); int pwm_set_chip_data(struct pwm_device *pwm, void *data); void *pwm_get_chip_data(struct pwm_device *pwm); @@ -373,6 +390,13 @@ static inline int pwm_config(struct pwm_device *pwm, int duty_ns, return -EINVAL; } +static inline int pwm_capture(struct pwm_device *pwm, + struct pwm_capture *result, + unsigned long timeout) +{ + return -EINVAL; +} + static inline int pwm_set_polarity(struct pwm_device *pwm, enum pwm_polarity polarity) { |