On Thu 2019-04-04 11:10:08, Nick Crews wrote: > The EC is in charge of controlling the keyboard backlight on > the Wilco platform. We expose a standard LED class device at > /sys/class/leds/platform::kbd_backlight. This driver is modeled > after the standard Chrome OS keyboard backlight driver at > drivers/platform/chrome/cros_kbd_led_backlight.c > > Some Wilco devices do not support a keyboard backlight. This > is checked via wilco_ec_keyboard_leds_exist() in the core driver, > and a platform_device will only be registered by the core if > a backlight is supported. > > After an EC reset the backlight could be in a non-PWM mode. > Earlier in the boot sequence the BIOS should send a command to > the EC to set the brightness, so things **should** be set up, > but we double check in probe() as we query the initial brightness. > If not set up, then set the brightness to 0. > > Since the EC will never change the backlight level of its own accord, > we don't need to implement a brightness_get() method. ... > Signed-off-by: Nick Crews <ncrews@xxxxxxxxxxxx> > Acked-by: Jacek Anaszewski <jacek.anaszewski@xxxxxxxxx> Acked-by: Pavel Machek <pavel@xxxxxx> -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
Attachment:
signature.asc
Description: Digital signature
