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Code Pull requests 5 Wiki Activity

pwm-backlight: Fix bogus request for GPIO#0 when instantiated from DT

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commit 257462dbf3 ("pwm-backlight: switch to gpiod interface")
introduced a regression leading to acquiring a bogus GPIO-0 when
configured from DT without an 'enable-gpios' property.
The driver will happily accept the 0 initialized 'enable_gpio' member
of the struct platform_pwm_backlight_data as valid gpio number, and
request this GPIO as enable pin. In case of multiple driver instances,
the second will fail to register with the error message:
pwm-backlight backlight1.23: failed to request GPIO#0: -16

Fix this by setting enable_gpio in the pdata struct to -EINVAL.

Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
This commit is contained in:
Lothar Waßmann 2014-08-20 08:38:36 +02:00 committed by Lee Jones
parent 7d1311b93e
commit 937222c4dd
1 changed files with 1 additions and 0 deletions
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1
drivers/video/backlight/pwm_bl.c
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@ -173,6 +173,7 @@ static int pwm_backlight_parse_dt(struct device *dev,
data->max_brightness--;
}
data->enable_gpio = -EINVAL;
return 0;
}