diff options
| author |   Lee Jones <lee.jones@linaro.org> | 2016-06-08 10:21:23 +0100 |
|---|---|---|
| committer |   Thierry Reding <thierry.reding@gmail.com> | 2016-06-10 16:01:35 +0200 |
| commit | 3a3d1a4e32ab47323d7b8c8b7631a8d36a3098b2 (patch) | |
| tree | a79165beca06b134c36ac6dd6ebbcd82e36d3206 /drivers/pwm | |
| parent | Linux 4.7-rc1 (diff) | |
| download | linux-dev-3a3d1a4e32ab47323d7b8c8b7631a8d36a3098b2.tar.xz linux-dev-3a3d1a4e32ab47323d7b8c8b7631a8d36a3098b2.zip | |
pwm: Add PWM capture support
Supply a PWM capture callback op in order to pass back information
obtained by running analysis on a PWM 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 <lee.jones@linaro.org>
[thierry.reding@gmail.com: make capture data unsigned int for symmetry]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Diffstat (limited to 'drivers/pwm')
| -rw-r--r-- | drivers/pwm/core.c | 27 |
1 files changed, 27 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 * |