pwm: mxs: Don't modify HW state in .probe() after the PWM chip was registered

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This fixes a race condition: After pwmchip_add() is called there might
already be a consumer and then modifying the hardware behind the
consumer's back is bad. So reset before calling pwmchip_add().

Note that reseting the hardware isn't the right thing to do if the PWM
is already running as it might e.g. disable (or even enable) a backlight
that is supposed to be on (or off).

Fixes: 4dce82c1e8 ("pwm: add pwm-mxs support")
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

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Uwe Kleine-König 2021-07-07 18:27:50 +02:00 • committed by Thierry Reding

parent 3d2813fb17

commit 020162d6f4

1 changed files with 5 additions and 8 deletions

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drivers/pwm/pwm-mxs.c

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