This is a note to let you know that I've just added the patch titled
pwm: tegra: Don't modify HW state in .remove callback
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
pwm-tegra-don-t-modify-hw-state-in-.remove-callback.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit d2a4916dc1085ee813541bd928b2e28262c89148
Author: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
Date: Thu Jun 17 11:51:41 2021 +0200
pwm: tegra: Don't modify HW state in .remove callback
[ Upstream commit 86f7fa71cd830d18d7ebcaf719dffd5ddfe1acdd ]
A consumer is expected to disable a PWM before calling pwm_put(). And if
they didn't there is hopefully a good reason (or the consumer needs
fixing). Also if disabling an enabled PWM was the right thing to do,
this should better be done in the framework instead of in each low level
driver.
So drop the hardware modification from the .remove() callback.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
Signed-off-by: Thierry Reding <thierry.reding@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/pwm/pwm-tegra.c b/drivers/pwm/pwm-tegra.c
index aa12fb3ed92e..3d55e30a6866 100644
--- a/drivers/pwm/pwm-tegra.c
+++ b/drivers/pwm/pwm-tegra.c
@@ -232,7 +232,6 @@ static int tegra_pwm_probe(struct platform_device *pdev)
static int tegra_pwm_remove(struct platform_device *pdev)
{
struct tegra_pwm_chip *pc = platform_get_drvdata(pdev);
- unsigned int i;
int err;
if (WARN_ON(!pc))
@@ -242,18 +241,6 @@ static int tegra_pwm_remove(struct platform_device *pdev)
if (err < 0)
return err;
- for (i = 0; i < pc->chip.npwm; i++) {
- struct pwm_device *pwm = &pc->chip.pwms[i];
-
- if (!pwm_is_enabled(pwm))
- if (clk_prepare_enable(pc->clk) < 0)
- continue;
-
- pwm_writel(pc, i, 0);
-
- clk_disable_unprepare(pc->clk);
- }
-
reset_control_assert(pc->rst);
clk_disable_unprepare(pc->clk);
