Re: [PATCH] Rationalise ACPI backlight implementation
From: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Date: 2008-01-28 15:52:06
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On Sun, 27 Jan 2008, Andrew Morton wrote:
0 sh -c "echo $1 > /sys/class/backlight/thinkpad_screen/brightness" ) 2>/dev/null And yes, I had an rc.local command which assumed that 7 (later 8) is max brightness.
You have to use 15 (or 16? I forget) on T61, X61, R61, X60(I think)... for maximum brightness :-p And the interface to get maximum brightness has always been to cat max_brightness > brightness, AFAIK.
My /sys/class/backlight/ directory is presently empty. Rather than trying to find out why, I think I'll just collapse in laughter.
Well, I can tell you why it is empty on the thinkpad-acpi side. It defaults to brightness_enable=0 on Lenovo 16-brightness level boxes, where the right thing to do is to control brightness using the X.org drivers or through the ACPI brightness driver. But I have no idea why it is empty re. the ACPI video driver.
Guys, sort it out, please.
I am reading this ML with eyes fully open. When a sensible (read: any) consensus is found, I will follow it. -- "One disk to rule them all, One disk to find them. One disk to bring them all and in the darkness grind them. In the Land of Redmond where the shadows lie." -- The Silicon Valley Tarot Henrique Holschuh