linux-kernel - [PATCH 5.12 164/292] pwm: tegra: Dont modify HW state in .remove callback

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Message-Id: <20210719144947.883092715@linuxfoundation.org>
Date:   Mon, 19 Jul 2021 16:53:46 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org,
        Uwe Kleine-König 
        <u.kleine-koenig@...gutronix.de>,
        Thierry Reding <thierry.reding@...il.com>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.12 164/292] pwm: tegra: Dont modify HW state in .remove callback

From: Uwe Kleine-König <u.kleine-koenig@...gutronix.de>

[ 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@...gutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@...il.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/pwm/pwm-tegra.c | 13 -------------
 1 file changed, 13 deletions(-)

diff --git a/drivers/pwm/pwm-tegra.c b/drivers/pwm/pwm-tegra.c
index 55bc63d5a0ae..6d8e324864fa 100644
--- a/drivers/pwm/pwm-tegra.c
+++ b/drivers/pwm/pwm-tegra.c
@@ -301,7 +301,6 @@ 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))
@@ -311,18 +310,6 @@ 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);
 
-- 
2.30.2