linux-kernel - [PATCH 1/5] pwm: pca9685: Don't disable hardware in .free()

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Message-ID:  <1ee1a514aeb5f0effafa2d6ec91bc54130895cd9.1753784092.git.u.kleine-koenig@baylibre.com>
Date: Tue, 29 Jul 2025 12:36:00 +0200
From: Uwe Kleine-König <u.kleine-koenig@...libre.com>
To: linux-pwm@...r.kernel.org
Cc: David Jander <david@...tonic.nl>,
	Clemens Gruber <clemens.gruber@...ruber.com>,
	linux-kernel@...r.kernel.org
Subject: [PATCH 1/5] pwm: pca9685: Don't disable hardware in .free()

It's the responsibility of the consumer to disable the hardware before
it's released. And there are use cases where it's beneficial to keep the
PWM on, e.g. to keep a backlight on before kexec()ing into a new kernel.

Even if it would be considered right to disable on pwm_put(), this
should be done in the core and not each individual driver. So drop the
hardware access in .free().

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@...libre.com>
---
 drivers/pwm/pwm-pca9685.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/pwm/pwm-pca9685.c b/drivers/pwm/pwm-pca9685.c
index eb03ccd5b688..41eb8e034828 100644
--- a/drivers/pwm/pwm-pca9685.c
+++ b/drivers/pwm/pwm-pca9685.c
@@ -497,7 +497,6 @@ static void pca9685_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
 	struct pca9685 *pca = to_pca(chip);
 
 	mutex_lock(&pca->lock);
-	pca9685_pwm_set_duty(chip, pwm->hwpwm, 0);
 	clear_bit(pwm->hwpwm, pca->pwms_enabled);
 	mutex_unlock(&pca->lock);
 
-- 
2.50.0