<html> <head> <base href="https://bugs.freedesktop.org/" /> </head> <body> <div> <a class="bz_bug_link bz_status_VERIFIED bz_closed" title="VERIFIED INVALID - [snb] backlight issue on TOSHIBA PORTEGE R830 after suspend/resume" href="https://bugs.freedesktop.org/show_bug.cgi?id=82634#c16">Comment # 16</a> on <a class="bz_bug_link bz_status_VERIFIED bz_closed" title="VERIFIED INVALID - [snb] backlight issue on TOSHIBA PORTEGE R830 after suspend/resume" href="https://bugs.freedesktop.org/show_bug.cgi?id=82634">bug 82634</a> from <a class="email" href="mailto:jwrdegoede@fedoraproject.org" title="Hans de Goede <jwrdegoede@fedoraproject.org>"> Hans de Goede</a> <pre>(In reply to Sylvain Pasche from <a href="show_bug.cgi?id=82634#c15">comment #15</a>) <snip> > I can change the brightness on both. > > After a suspend+resume: > > The backlight is turned on. > changing brightness of acpi_video0 has no effect > changing brightness of intel_backlight works Ok, so it seems that the 2 backlight control methods are getting in each others way, and disabling the acpi_video0 one is not an option as then the backlight does not go back on after a suspend/resume. So lets try disabling the intel backlight control. I've done a scratch kernel build for F-22 with a patch which adds a module param which allows you to tell the intel driver to not touch the backlight: <a href="http://koji.fedoraproject.org/koji/taskinfo?taskID=9865887">http://koji.fedoraproject.org/koji/taskinfo?taskID=9865887</a> Please install this kernel and then boot into it with: "i915.enable_backlight_control=0" (and no other backlight related options) added to the kernel commandline, then do: ls /sys/class/backlight And you should only see acpi_video0 there, then try if backlight control works, then suspend/resume and check if backlight control still works. I'll attach the patch I did here in case anyone following this wants to take a look, I'll submit it upstream once we've confirmed that it helps :) Regards, Hans</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> <li>You are on the CC list for the bug.</li> <li>You are the assignee for the bug.</li> </ul> </body> </html>