6.12-stable review patch. If anyone has any objections, please let me know.
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From: Uwe Kleine-König u.kleine-koenig@baylibre.com
[ Upstream commit 21a5e91fda50fc662ce1a12bd0aae9d103455b43 ]
The pwm driver calls pm_runtime_get_sync() when the hardware becomes enabled and pm_runtime_put_sync() when it becomes disabled. The PWM's state is kept when a consumer goes away, so the call to pm_runtime_put_sync() in the .free() callback is unbalanced resulting in a non-functional device and a reference underlow for the second consumer.
The easiest fix for that issue is to just not drop the runtime PM reference in .free(), so do that.
Fixes: 19891b20e7c2 ("pwm: pwm-tiehrpwm: PWM driver support for EHRPWM") Signed-off-by: Uwe Kleine-König u.kleine-koenig@baylibre.com Link: https://lore.kernel.org/r/bbb089c4b5650cc1f7b25cf582d817543fd25384.175492768... Signed-off-by: Uwe Kleine-König ukleinek@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/pwm/pwm-tiehrpwm.c | 5 ----- 1 file changed, 5 deletions(-)
diff --git a/drivers/pwm/pwm-tiehrpwm.c b/drivers/pwm/pwm-tiehrpwm.c index 0125e73b98dfb..5e674a7bbf3be 100644 --- a/drivers/pwm/pwm-tiehrpwm.c +++ b/drivers/pwm/pwm-tiehrpwm.c @@ -391,11 +391,6 @@ static void ehrpwm_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) { struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
- if (pwm_is_enabled(pwm)) { - dev_warn(pwmchip_parent(chip), "Removing PWM device without disabling\n"); - pm_runtime_put_sync(pwmchip_parent(chip)); - } - /* set period value to zero on free */ pc->period_cycles[pwm->hwpwm] = 0; }