[Bug 67454] After suspend/resume, screen is black for all but the highest levels with i915 driver on MacBook Air 6,2

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=67454

Yuan Chao <yuanchao at gmail.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |VERIFIED

--- Comment #104 from Yuan Chao <yuanchao at gmail.com> ---
The same problem still exists on Ubuntu 16.04 with MacBook Air 6,2. I also
tried the latest kernel 4.8-rc3, and found the issue is still there.

Following a similar [Bug 97486], I checked the register values before and after
S3 suspend:

$ sudo ./intel_reg read 0xc2004
                                    (0x000c2004): 0x00000024
$ sudo ./intel_reg read 0xc2000
                                    (0x000c2000): 0x00000000

$ sudo pm-suspend; sleep 10; sudo ./intel_reg read 0xc2004
                                    (0x000c2004): 0x00000004
$ sudo ./intel_reg read 0xc2000
                                    (0x000c2000): 0x00000000

Then trying to write back the value of 0xc2004, the back light level seems to
become normal. A similar patch from [Bug 97486] would be applied here?

-- 
You are receiving this mail because:
You are the QA Contact for the bug.
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/intel-gfx-bugs/attachments/20160909/6fc56248/attachment.html>