[PATCH 01/11] pwm: Add PWM Capture support
From: Lee Jones <hidden>
Date: 2016-02-10 13:08:35
Also in:
linux-pwm, lkml
Subsystem:
pwm subsystem, the rest · Maintainers:
Uwe Kleine-König, Linus Torvalds
Supply a PWM Capture call-back Op in order to pass back information obtained by running analysis on PWM a signal. This would normally (at least during testing) be called from the Sysfs routines with a view to printing out PWM Capture data which has been encoded into a string. Signed-off-by: Lee Jones <redacted> --- drivers/pwm/core.c | 26 ++++++++++++++++++++++++++ include/linux/pwm.h | 13 +++++++++++++ 2 files changed, 39 insertions(+)
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index d24ca5f..8f4a8a9 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c@@ -494,6 +494,32 @@ unlock: EXPORT_SYMBOL_GPL(pwm_set_polarity); /** + * pwm_capture() - capture and report a PWM signal + * @pwm: PWM device + * @channel: PWM capture channel to use + * @buf: buffer to place output message into + * + * Returns: 0 on success or a negative error code on failure. + */ +int pwm_capture(struct pwm_device *pwm, int channel, char *buf) +{ + 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, channel, buf); + mutex_unlock(&pwm->lock); + + return err; +} +EXPORT_SYMBOL_GPL(pwm_capture); + +/** * pwm_enable() - start a PWM output toggling * @pwm: PWM device *
diff --git a/include/linux/pwm.h b/include/linux/pwm.h
index cfc3ed4..7bcff6b 100644
--- a/include/linux/pwm.h
+++ b/include/linux/pwm.h@@ -33,6 +33,11 @@ int pwm_enable(struct pwm_device *pwm); * pwm_disable - stop a PWM output toggling */ void pwm_disable(struct pwm_device *pwm); + +/* + * pwm_capture - capture and report a PWM signal + */ +int pwm_capture(struct pwm_device *pwm, int channel, char *buf); #else static inline struct pwm_device *pwm_request(int pwm_id, const char *label) {
@@ -56,6 +61,11 @@ static inline int pwm_enable(struct pwm_device *pwm) static inline void pwm_disable(struct pwm_device *pwm) { } + +static inline int pwm_capture(struct pwm_device *pwm, int channel, char *buf) +{ + return -EINVAL; +} #endif struct pwm_chip;
@@ -150,6 +160,7 @@ static inline enum pwm_polarity pwm_get_polarity(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 * @dbg_show: optional routine to show contents in debugfs
@@ -162,6 +173,8 @@ 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, + int channel, char *buf); int (*enable)(struct pwm_chip *chip, struct pwm_device *pwm); void (*disable)(struct pwm_chip *chip, struct pwm_device *pwm); #ifdef CONFIG_DEBUG_FS
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1.9.1