From 034968dbd86704932a9cdd6f5b434922b912cd65 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= Date: Wed, 17 Apr 2024 17:38:47 +0200 Subject: [PATCH] leds: pwm: Disable PWM when going to suspend MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ 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 Link: https://lore.kernel.org/r/20240417153846.271751-2-u.kleine-koenig@pengutronix.de Signed-off-by: Lee Jones Signed-off-by: Sasha Levin --- 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); }