<html> <head> <base href="https://bugs.freedesktop.org/" /> </head> <body> <div> <a class="bz_bug_link bz_status_NEEDINFO " title="NEEDINFO --- - [HSW ULT]eDP brightness is zero after the computer start" href="https://bugs.freedesktop.org/show_bug.cgi?id=70791#c7">Comment # 7</a> on <a class="bz_bug_link bz_status_NEEDINFO " title="NEEDINFO --- - [HSW ULT]eDP brightness is zero after the computer start" href="https://bugs.freedesktop.org/show_bug.cgi?id=70791">bug 70791</a> from <a class="email" href="mailto:aaron.lu@intel.com" title="Aaron Lu <aaron.lu@intel.com>"> Aaron Lu</a> <pre>(In reply to <a href="show_bug.cgi?id=70791#c6">comment #6</a>) > (In reply to <a href="show_bug.cgi?id=70791#c5">comment #5</a>) > > I tried video.use_bios_initial_backlight=0 parameter on latest > > drm-intel-next-queued branch. The eDP works well and won't turn into black > > again. > > Aaron, possibly another one for an ACPI initial backlight quirk. Although > I'm slightly surprised your win8 native backlight patches don't help. Me too, surprised. The video.use_bios_initial_backlight=0 will cause ACPI video not do a backlight level set based on value from _BQC, which might be buggy for a first time evaluation. But if my win8 native backlight patches got applied and video.use_native_backlight=1 is set, that set is also skipped, so it should solve the problem too... Hi Qingshuai, Can you please verify, with the win8 native backlight patch applied and video.use_native_backlight=1 set in kernel cmdline, there is no acpi_video0 in /sys/class/backlight. > > For future reference, would you like to have new bug reports on > bugzilla.kernel.org for these, or is it okay to re-assign the bugs here to > you? I'm OK with both ways :-)</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>