Re: no backlight on radeon after recent kernel "upgrade"s
From: Richard Purdie <hidden>
Date: 2007-02-22 00:35:00
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On Wed, 2007-02-21 at 00:56 -0500, Yaroslav Halchenko wrote:
I didn't mention 2.6.20-mm1 and got to see -mm2 so it is the one which Iv'e tried, but, once again, I experienced the same issue with 19-mm? kernels. I built 2.6.20-mm2 without backlight support $> grep BACKLIGH /boot/config-2.6.20-mm2 # CONFIG_BACKLIGHT_LCD_SUPPORT is not set # CONFIG_FB_BACKLIGHT is not set # CONFIG_FB_RIVA_BACKLIGHT is not set # CONFIG_FB_RADEON_BACKLIGHT is not set that "eliminated" the problem. Also I can see the screen with pure 2.6.20 with backlight support (whatever it does since after loading lcd, backlight modules, my /sys/class/{lcd,backlight} are empty): *$> grep BACKLIGH /boot/config-2.6.20 # CONFIG_FB_BACKLIGHT is not set CONFIG_BACKLIGHT_LCD_SUPPORT=y CONFIG_BACKLIGHT_CLASS_DEVICE=m CONFIG_BACKLIGHT_DEVICE=yquoted
Also, do you normally see files under /sys/class/lcd?nope... after I load lcd module, no files under :-/ regardless either it is mm or not. But there are files under /sys/class/backlight/ for mm2 compiled with backlight support (whenever the screen is dark as per my original email)
There should be no files appearing under /sys/class/lcd, so thats all normal. There is another report with similar symptoms which also sounds like enabling the following options are at fault: # CONFIG_FB_RIVA_BACKLIGHT is not set # CONFIG_FB_RADEON_BACKLIGHT is not set I suspect these options only work on certain hardware and aren't generic. James, any idea what hardware these do/don't work with? Worst case, we set them to depend on PMAC_BACKLIGHT again I guess... Richard ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV