From: Uwe Kleine-König u.kleine-koenig@pengutronix.de
stable inclusion from stable-v6.6.33 commit 034968dbd86704932a9cdd6f5b434922b912cd65 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/IAD6H2
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ Upstream commit 974afccd37947a6951a052ef8118c961e57eaf7b ]
On stm32mp1xx based machines (and others) a PWM consumer has to disable the PWM because an enabled PWM refuses to suspend. So check the LED_SUSPENDED flag and depending on that set the .enabled property.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=218559 Fixes: 76fe464c8e64 ("leds: pwm: Don't disable the PWM when the LED should be off") Signed-off-by: Uwe Kleine-König u.kleine-koenig@pengutronix.de Link: https://lore.kernel.org/r/20240417153846.271751-2-u.kleine-koenig@pengutroni... Signed-off-by: Lee Jones lee@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Wang Hai wanghai38@huawei.com --- drivers/leds/leds-pwm.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/leds/leds-pwm.c b/drivers/leds/leds-pwm.c index 4e3936a39d0e..e1b414b40353 100644 --- a/drivers/leds/leds-pwm.c +++ b/drivers/leds/leds-pwm.c @@ -53,7 +53,13 @@ static int led_pwm_set(struct led_classdev *led_cdev, duty = led_dat->pwmstate.period - duty;
led_dat->pwmstate.duty_cycle = duty; - led_dat->pwmstate.enabled = true; + /* + * Disabling a PWM doesn't guarantee that it emits the inactive level. + * So keep it on. Only for suspending the PWM should be disabled because + * otherwise it refuses to suspend. The possible downside is that the + * LED might stay (or even go) on. + */ + led_dat->pwmstate.enabled = !(led_cdev->flags & LED_SUSPENDED); return pwm_apply_might_sleep(led_dat->pwm, &led_dat->pwmstate); }