diff options
| author | Uwe Kleine-König <u.kleine-koenig@pengutronix.de> | 2022-12-02 19:35:36 +0100 |
|---|---|---|
| committer | Thierry Reding <thierry.reding@gmail.com> | 2022-12-06 12:46:29 +0100 |
| commit | c73a3107624ddc305483ced13deca9ce8a073783 (patch) | |
| tree | 16ea7566a4aa42fd60f752b86e32f840964aaedf /drivers/pwm | |
| parent | 500f879843adf329281e418d302e1ad40baa26c3 (diff) | |
| download | linux-c73a3107624ddc305483ced13deca9ce8a073783.tar.bz2 | |
pwm: Handle .get_state() failures
This suppresses diagnosis for PWM_DEBUG routines and makes sure that
pwm->state isn't modified in pwm_device_request() if .get_state() fails.
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20221130152148.2769768-12-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Diffstat (limited to 'drivers/pwm')
| -rw-r--r-- | drivers/pwm/core.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c index 61d15510fdd7..e01147f66e15 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -115,8 +115,13 @@ static int pwm_device_request(struct pwm_device *pwm, const char *label) } if (pwm->chip->ops->get_state) { - err = pwm->chip->ops->get_state(pwm->chip, pwm, &pwm->state); - trace_pwm_get(pwm, &pwm->state, err); + struct pwm_state state; + + err = pwm->chip->ops->get_state(pwm->chip, pwm, &state); + trace_pwm_get(pwm, &state, err); + + if (!err) + pwm->state = state; if (IS_ENABLED(CONFIG_PWM_DEBUG)) pwm->last = pwm->state; @@ -460,6 +465,9 @@ static void pwm_apply_state_debug(struct pwm_device *pwm, err = chip->ops->get_state(chip, pwm, &s1); trace_pwm_get(pwm, &s1, err); + if (err) + /* If that failed there isn't much to debug */ + return; /* * The lowlevel driver either ignored .polarity (which is a bug) or as @@ -524,6 +532,8 @@ static void pwm_apply_state_debug(struct pwm_device *pwm, err = chip->ops->get_state(chip, pwm, last); trace_pwm_get(pwm, last, err); + if (err) + return; /* reapplication of the current state should give an exact match */ if (s1.enabled != last->enabled || |