linux-kernel - [PATCH AUTOSEL 4.14 1/2] pwm: rockchip: Don't modify HW state in .remove() callback

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Message-Id: <20210917023504.816909-1-sashal@kernel.org>
Date:   Thu, 16 Sep 2021 22:35:03 -0400
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Uwe Kleine-König 
        <u.kleine-koenig@...gutronix.de>,
        Thierry Reding <thierry.reding@...il.com>,
        Sasha Levin <sashal@...nel.org>, lee.jones@...aro.org,
        heiko@...ech.de, linux-pwm@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org,
        linux-rockchip@...ts.infradead.org
Subject: [PATCH AUTOSEL 4.14 1/2] pwm: rockchip: Don't modify HW state in .remove() callback

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

[ Upstream commit 9d768cd7fd42bb0be16f36aec48548fca5260759 ]

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.

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-rockchip.c | 14 --------------
 1 file changed, 14 deletions(-)

diff --git a/drivers/pwm/pwm-rockchip.c b/drivers/pwm/pwm-rockchip.c
index 48bcc853d57a..cf34fb00c054 100644
--- a/drivers/pwm/pwm-rockchip.c
+++ b/drivers/pwm/pwm-rockchip.c
@@ -392,20 +392,6 @@ static int rockchip_pwm_remove(struct platform_device *pdev)
 {
 	struct rockchip_pwm_chip *pc = platform_get_drvdata(pdev);
 
-	/*
-	 * Disable the PWM clk before unpreparing it if the PWM device is still
-	 * running. This should only happen when the last PWM user left it
-	 * enabled, or when nobody requested a PWM that was previously enabled
-	 * by the bootloader.
-	 *
-	 * FIXME: Maybe the core should disable all PWM devices in
-	 * pwmchip_remove(). In this case we'd only have to call
-	 * clk_unprepare() after pwmchip_remove().
-	 *
-	 */
-	if (pwm_is_enabled(pc->chip.pwms))
-		clk_disable(pc->clk);
-
 	clk_unprepare(pc->pclk);
 	clk_unprepare(pc->clk);
 
-- 
2.30.2