PWM output from ecap2 uses as backlight source. Also adds low threshold
value to have a uniform divisions in brightness-levels scales with
inverse polarity.
Signed-off-by: NPhilip Avinash <avinashphilip@ti.com>
Reviewed-by: NThierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NBenoit Cousson <benoit.cousson@linaro.org>