tree 7f1b90e12d709dc2ea34bd1cd8e2dd704ffac23b
parent 8777078015bb77f0561303b6dea23d40bd9f3053
author Stefan Agner <stefan@agner.ch> 1445643883 -0700
committer Lee Jones <lee.jones@linaro.org> 1452499115 +0000

backlight: gpio-backlight: Use default-on on GPIO request

There are situations where the backlight should be on at boot time
(e.g. if the boot loader already turned the display on). The DT
bindings specify the "default-on" property for that purpose.
Currently, the initial state of the GPIO at request time is always
set to logical off (high or low depending on whether it is an
active high or low GPIO). Since the GPIO is requested as an output,
the GPIO will be driven low for a short period of time, which leads
to a flickering display in the above use-case.

Initialize the GPIO depending on the default-on property to be
logical on or off.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Lee Jones <lee.jones@linaro.org>