Commit c73a3107 authored by Uwe Kleine-König's avatar Uwe Kleine-König Committed by Thierry Reding
Browse files

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: default avatarConor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20221130152148.2769768-12-u.kleine-koenig@pengutronix.de


Signed-off-by: default avatarUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: default avatarThierry Reding <thierry.reding@gmail.com>
parent 500f8798

drivers/pwm/core.c

+12 −2
Original line number Diff line number Diff line
@@ -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 ||