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hwmon: (pwm-fan) Ensure the fan going on in .probe()

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commit a2ca752055 upstream.

Before commit 86585c6197 ("hwmon: (pwm-fan) stop using legacy
PWM functions and some cleanups") pwm_apply_state() was called
unconditionally in pwm_fan_probe(). In this commit this direct
call was replaced by a call to __set_pwm(ct, MAX_PWM) which
however is a noop if ctx->pwm_value already matches the value to
set.
After probe the fan is supposed to run at full speed, and the
internal driver state suggests it does, but this isn't asserted
and depending on bootloader and pwm low-level driver, the fan
might just be off.
So drop setting pwm_value to MAX_PWM to ensure the check in
__set_pwm doesn't make it exit early and the fan goes on as
intended.

Cc: stable@vger.kernel.org
Fixes: 86585c6197 ("hwmon: (pwm-fan) stop using legacy PWM functions and some cleanups")
Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20211130092212.17783-1-billy_tsai@aspeedtech.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Billy Tsai 2021-11-30 17:22:12 +08:00 committed by Greg Kroah-Hartman
parent a85d27b2ef
commit 62c6134195
1 changed files with 0 additions and 2 deletions
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2
drivers/hwmon/pwm-fan.c
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@ -336,8 +336,6 @@ static int pwm_fan_probe(struct platform_device *pdev)
return ret;
}
ctx->pwm_value = MAX_PWM;
pwm_init_state(ctx->pwm, &ctx->pwm_state);
/*