From: Craig H. <cr...@gu...> - 2007-09-28 20:28:53
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On Sep 28, 2007, at 11:05 AM, Heilpern, Mark wrote: > I would like to be able to enable / disable the LCD from a driver > module. I see that I can dim the backlighting by controlling > GPIO17. Is > there a GPIO that corresponds to /sys/class/graphics/fb0/blank? > Or... is > there some kernel function I can call to control the LED's state? I > imagine this is a generic kernel task, as the functions in pxafb.c are > static entrypoints in a table. Don't hit GPIO17 directly. Use /sys/class/graphics/fb0/blank -- echo 1 to that to turn off backlight and blank the screen; echo 0 to turn back on. The FB driver will in turn toggle GPIO17 the correct way for you. There is probably a linux console ESC sequence which will initiate the blanking (and cause the driver to twiddle the GPIO too) as well. C |