Hi! > >> If that does not yet exist... you want to create glue layer to be able > >> to use LED as a display backlight. (It may already exist, no idea). > >> > >> ... > >> > >> Actually or maybe a LED trigger. Just set LED's trigger to "this is > >> display backlight". > > > > There is one already: > > > > drivers/leds/trigger/ledtrig-backlight.c > > > > It adds a LED class device to the fb_notifier_list > > (drivers/video/fbdev/core/fb_notify.c) > > > > using fb_register_client(). The same is used in > > backlight_device_register (drivers/video/backlight/backlight.c). > > > > Actually why do you want to have this driver in the LED subsystem, > > if it is advertised as "designed for LCD display backlighting"? > > Well this is also advertised as a driver for Smart phone and tablet devices. And having worked with the Android lighting > solutions this is the preferred subsystem for Android. The Android OS manages the led brightness based on ALS values and in > turn calls into the driver to control the brightness register through the vendor provided lighting HAL. > Well.. if it can control other LEDs than just backlight, I believe it can stay in the LED subsystem. > I am going to look at the backlight source to figure out how to get the same functionality using the backlight subsystem. > Otherwise I will plug in this driver to the backlight subsystem through the notifier. > The backlight trigger should be ok. Best regards, Pavel -- (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
