From c73a3107624ddc305483ced13deca9ce8a073783 Mon Sep 17 00:00:00 2001 From: Uwe Kleine-König Date: Fri, 2 Dec 2022 19:35:36 +0100 Subject: pwm: Handle .get_state() failures MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Link: https://lore.kernel.org/r/20221130152148.2769768-12-u.kleine-koenig@pengutronix.de Signed-off-by: Uwe Kleine-König Signed-off-by: Thierry Reding --- drivers/pwm/core.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) (limited to 'drivers/pwm/core.c') 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 || -- cgit v1.2.3