* Re: [Bugme-new] [Bug 12235] New: /sys/devices/virtual/backlight/acpi_video0/brightness has it backwards
[not found] <bug-12235-10286@http.bugzilla.kernel.org/>
@ 2008-12-16 18:00 ` Andrew Morton
2008-12-16 20:55 ` Matthew Garrett
0 siblings, 1 reply; 5+ messages in thread
From: Andrew Morton @ 2008-12-16 18:00 UTC (permalink / raw)
To: linux-acpi; +Cc: bugme-daemon, khashayar.lists, Rafael J. Wysocki, Zhang Rui
(switched to email. Please respond via emailed reply-to-all, not via the
bugzilla web interface).
On Tue, 16 Dec 2008 03:36:11 -0800 (PST) bugme-daemon@bugzilla.kernel.org wrote:
> http://bugzilla.kernel.org/show_bug.cgi?id=12235
>
> Summary: /sys/devices/virtual/backlight/acpi_video0/brightness
> has it backwards
> Product: ACPI
> Version: 2.5
> KernelVersion: 2.6.28-rc8
> Platform: All
> OS/Version: Linux
> Tree: Mainline
> Status: NEW
> Severity: normal
> Priority: P1
> Component: Power-Video
> AssignedTo: acpi_power-video@kernel-bugs.osdl.org
> ReportedBy: khashayar.lists@gmail.com
>
>
> Latest working kernel version:
> 2.6.27
>
> Earliest failing kernel version:
> probably 2.6.28-rc1, but could be later in the release candidates.
>
> Distribution:
> Ubuntu 8.10
>
> Hardware Environment:
> Asus, N20A, all intel.
>
> Problem Description:
> If the laptop loads the video module at boot time,
> /sys/devices/virtual/backlight/acpi_video0/brightness is created. However, it's
> all backwards, confusing applications like gnome-power-manager and the likes
> (well, that basically means hal). Echoing 0 to 'brightness' raises the
> backlight of this laptop to maximum. Echoing 13 to it, takes the backlight to a
> minimum.
> actual_brightness' seems to stay at 0 at all times.
>
> If I disalllow the video module to be loaded at boot time, there's no backlight
> interface in /sys/class/backlight/*. But, nevertheless, the xbacklight utility
> and hal seem to be able to control the backlight just fine. In this latter
> case, withouth the video module loaded, xbacklight & hal handle the backlight
> correctly, i.e. less means lower backlight, and more means brighter backlight.
>
> I just confirmed this problem exists with the latest git from Linus' tree, as
> well as the rc8 patch.
>
> If I remember correctly, the 2.6.27-series created an interface under
> /sys/devices/platform/asus-laptop/ for controlling backlight which worked just
> fine.
>
> Please let me know what additional information to post. I'd love to have this
> fixed before the 2.6.28 release.
OK, that's weird. I have a suspicion that we're about to find out that
this is intentional, but I don't know what the fix is..
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [Bugme-new] [Bug 12235] New: /sys/devices/virtual/backlight/acpi_video0/brightness has it backwards
2008-12-16 18:00 ` [Bugme-new] [Bug 12235] New: /sys/devices/virtual/backlight/acpi_video0/brightness has it backwards Andrew Morton
@ 2008-12-16 20:55 ` Matthew Garrett
2008-12-17 0:57 ` Zhang Rui
0 siblings, 1 reply; 5+ messages in thread
From: Matthew Garrett @ 2008-12-16 20:55 UTC (permalink / raw)
To: Andrew Morton
Cc: linux-acpi, bugme-daemon, khashayar.lists, Rafael J. Wysocki, Zhang Rui
On Tue, Dec 16, 2008 at 10:00:23AM -0800, Andrew Morton wrote:
> OK, that's weird. I have a suspicion that we're about to find out that
> this is intentional, but I don't know what the fix is..
My recollection is that some BIOSes provide the list of brightness
values in reverse order - someone posted a patch to sort them in-kernel,
but I can't remember what happened to it. xbacklight will work because
it triggers a direct write to the hardware if the acpi driver isn't
loaded.
--
Matthew Garrett | mjg59@srcf.ucam.org
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [Bugme-new] [Bug 12235] New: /sys/devices/virtual/backlight/acpi_video0/brightness has it backwards
2008-12-16 20:55 ` Matthew Garrett
@ 2008-12-17 0:57 ` Zhang Rui
2008-12-17 9:44 ` Khashayar Naderehvandi
0 siblings, 1 reply; 5+ messages in thread
From: Zhang Rui @ 2008-12-17 0:57 UTC (permalink / raw)
To: Matthew Garrett
Cc: Andrew Morton, linux-acpi, bugme-daemon, khashayar.lists,
Rafael J. Wysocki
On Wed, 2008-12-17 at 04:55 +0800, Matthew Garrett wrote:
> On Tue, Dec 16, 2008 at 10:00:23AM -0800, Andrew Morton wrote:
>
> > OK, that's weird. I have a suspicion that we're about to find out that
> > this is intentional, but I don't know what the fix is..
>
> My recollection is that some BIOSes provide the list of brightness
> values in reverse order - someone posted a patch to sort them in-kernel,
> but I can't remember what happened to it. xbacklight will work because
> it triggers a direct write to the hardware if the acpi driver isn't
> loaded.
>
right, this seems to be a duplicate of
http://bugzilla.kernel.org/show_bug.cgi?id=12037
khashayar,
please attach the result of "grep . /proc/acpi/video/*/*/*".
please try the patch in
http://bugzilla.kernel.org/show_bug.cgi?id=12037#c5
and see if it helps.
thanks,
rui
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [Bugme-new] [Bug 12235] New: /sys/devices/virtual/backlight/acpi_video0/brightness has it backwards
2008-12-17 0:57 ` Zhang Rui
@ 2008-12-17 9:44 ` Khashayar Naderehvandi
2008-12-17 19:56 ` Khashayar Naderehvandi
0 siblings, 1 reply; 5+ messages in thread
From: Khashayar Naderehvandi @ 2008-12-17 9:44 UTC (permalink / raw)
To: Zhang Rui
Cc: Matthew Garrett, Andrew Morton, linux-acpi, bugme-daemon,
Rafael J. Wysocki
On Wed, Dec 17, 2008 at 1:57 AM, Zhang Rui <rui.zhang@intel.com> wrote:
> On Wed, 2008-12-17 at 04:55 +0800, Matthew Garrett wrote:
>> On Tue, Dec 16, 2008 at 10:00:23AM -0800, Andrew Morton wrote:
>>
>> > OK, that's weird. I have a suspicion that we're about to find out that
>> > this is intentional, but I don't know what the fix is..
>>
>> My recollection is that some BIOSes provide the list of brightness
>> values in reverse order - someone posted a patch to sort them in-kernel,
>> but I can't remember what happened to it. xbacklight will work because
>> it triggers a direct write to the hardware if the acpi driver isn't
>> loaded.
>>
> right, this seems to be a duplicate of
> http://bugzilla.kernel.org/show_bug.cgi?id=12037
>
> khashayar,
> please attach the result of "grep . /proc/acpi/video/*/*/*".
> please try the patch in
> http://bugzilla.kernel.org/show_bug.cgi?id=12037#c5
> and see if it helps.
>
Here's the output of "grep . /proc/acpi/video/*/*/*". The video module
wasn't loaded at boot time, but just before greping. I don't know if
that has any relevance. Also, there's an external display attached at
this point.
/proc/acpi/video/VGA/CRTD/brightness:<not supported>
/proc/acpi/video/VGA/CRTD/EDID:<not supported>
/proc/acpi/video/VGA/CRTD/info:device_id: 0x0100
/proc/acpi/video/VGA/CRTD/info:type: CRT
/proc/acpi/video/VGA/CRTD/info:known by bios: yes
/proc/acpi/video/VGA/CRTD/state:state: 0x1d
/proc/acpi/video/VGA/CRTD/state:query: 0x00
/proc/acpi/video/VGA/DVID/brightness:<not supported>
/proc/acpi/video/VGA/DVID/EDID:<not supported>
/proc/acpi/video/VGA/DVID/info:device_id: 0x0321
/proc/acpi/video/VGA/DVID/info:type: DVI
/proc/acpi/video/VGA/DVID/info:known by bios: yes
/proc/acpi/video/VGA/DVID/state:state: 0x1d
/proc/acpi/video/VGA/DVID/state:query: 0x00
/proc/acpi/video/VGA/HDMI/brightness:<not supported>
/proc/acpi/video/VGA/HDMI/EDID:<not supported>
/proc/acpi/video/VGA/HDMI/info:device_id: 0x7320
/proc/acpi/video/VGA/HDMI/info:type: DVI
/proc/acpi/video/VGA/HDMI/info:known by bios: yes
/proc/acpi/video/VGA/HDMI/state:state: 0x1d
/proc/acpi/video/VGA/HDMI/state:query: 0x00
/proc/acpi/video/VGA/LCDD/brightness:levels: 100 91 86 81 76 70 65 60
55 50 45 40 35 30 25 20
/proc/acpi/video/VGA/LCDD/brightness:current: 86
/proc/acpi/video/VGA/LCDD/EDID:<not supported>
/proc/acpi/video/VGA/LCDD/info:device_id: 0x0410
/proc/acpi/video/VGA/LCDD/info:type: LCD
/proc/acpi/video/VGA/LCDD/info:known by bios: yes
/proc/acpi/video/VGA/LCDD/state:state: 0x1d
/proc/acpi/video/VGA/LCDD/state:query: 0x00
I will try the patch as soon as I can, and get back to you.
> thanks,
> rui
>
Thank you,
Khash.
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [Bugme-new] [Bug 12235] New: /sys/devices/virtual/backlight/acpi_video0/brightness has it backwards
2008-12-17 9:44 ` Khashayar Naderehvandi
@ 2008-12-17 19:56 ` Khashayar Naderehvandi
0 siblings, 0 replies; 5+ messages in thread
From: Khashayar Naderehvandi @ 2008-12-17 19:56 UTC (permalink / raw)
To: Zhang Rui
Cc: Matthew Garrett, Andrew Morton, linux-acpi, bugme-daemon,
Rafael J. Wysocki
On Wed, Dec 17, 2008 at 10:44 AM, Khashayar Naderehvandi
<khashayar.lists@gmail.com> wrote:
> On Wed, Dec 17, 2008 at 1:57 AM, Zhang Rui <rui.zhang@intel.com> wrote:
>> On Wed, 2008-12-17 at 04:55 +0800, Matthew Garrett wrote:
>>> On Tue, Dec 16, 2008 at 10:00:23AM -0800, Andrew Morton wrote:
>>>
>>> > OK, that's weird. I have a suspicion that we're about to find out that
>>> > this is intentional, but I don't know what the fix is..
>>>
>>> My recollection is that some BIOSes provide the list of brightness
>>> values in reverse order - someone posted a patch to sort them in-kernel,
>>> but I can't remember what happened to it. xbacklight will work because
>>> it triggers a direct write to the hardware if the acpi driver isn't
>>> loaded.
>>>
>> right, this seems to be a duplicate of
>> http://bugzilla.kernel.org/show_bug.cgi?id=12037
>>
>> khashayar,
>> please attach the result of "grep . /proc/acpi/video/*/*/*".
>> please try the patch in
>> http://bugzilla.kernel.org/show_bug.cgi?id=12037#c5
>> and see if it helps.
>>
> Here's the output of "grep . /proc/acpi/video/*/*/*". The video module
> wasn't loaded at boot time, but just before greping. I don't know if
> that has any relevance. Also, there's an external display attached at
> this point.
>
> /proc/acpi/video/VGA/CRTD/brightness:<not supported>
> /proc/acpi/video/VGA/CRTD/EDID:<not supported>
> /proc/acpi/video/VGA/CRTD/info:device_id: 0x0100
> /proc/acpi/video/VGA/CRTD/info:type: CRT
> /proc/acpi/video/VGA/CRTD/info:known by bios: yes
> /proc/acpi/video/VGA/CRTD/state:state: 0x1d
> /proc/acpi/video/VGA/CRTD/state:query: 0x00
> /proc/acpi/video/VGA/DVID/brightness:<not supported>
> /proc/acpi/video/VGA/DVID/EDID:<not supported>
> /proc/acpi/video/VGA/DVID/info:device_id: 0x0321
> /proc/acpi/video/VGA/DVID/info:type: DVI
> /proc/acpi/video/VGA/DVID/info:known by bios: yes
> /proc/acpi/video/VGA/DVID/state:state: 0x1d
> /proc/acpi/video/VGA/DVID/state:query: 0x00
> /proc/acpi/video/VGA/HDMI/brightness:<not supported>
> /proc/acpi/video/VGA/HDMI/EDID:<not supported>
> /proc/acpi/video/VGA/HDMI/info:device_id: 0x7320
> /proc/acpi/video/VGA/HDMI/info:type: DVI
> /proc/acpi/video/VGA/HDMI/info:known by bios: yes
> /proc/acpi/video/VGA/HDMI/state:state: 0x1d
> /proc/acpi/video/VGA/HDMI/state:query: 0x00
> /proc/acpi/video/VGA/LCDD/brightness:levels: 100 91 86 81 76 70 65 60
> 55 50 45 40 35 30 25 20
> /proc/acpi/video/VGA/LCDD/brightness:current: 86
> /proc/acpi/video/VGA/LCDD/EDID:<not supported>
> /proc/acpi/video/VGA/LCDD/info:device_id: 0x0410
> /proc/acpi/video/VGA/LCDD/info:type: LCD
> /proc/acpi/video/VGA/LCDD/info:known by bios: yes
> /proc/acpi/video/VGA/LCDD/state:state: 0x1d
> /proc/acpi/video/VGA/LCDD/state:query: 0x00
>
>
> I will try the patch as soon as I can, and get back to you.
>
I've now tried the patch and can confirm that it fixes the problem.
Well, almost; I'm now having the same issue reported in comment 8,
http://bugzilla.kernel.org/show_bug.cgi?id=12037#c8.
But that, I guess, is a whole other thing. Thanks for this one, though!
Will the patch be part of the 2.6.28 final release?
Regards,
Khash.
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2008-12-17 19:56 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
[not found] <bug-12235-10286@http.bugzilla.kernel.org/>
2008-12-16 18:00 ` [Bugme-new] [Bug 12235] New: /sys/devices/virtual/backlight/acpi_video0/brightness has it backwards Andrew Morton
2008-12-16 20:55 ` Matthew Garrett
2008-12-17 0:57 ` Zhang Rui
2008-12-17 9:44 ` Khashayar Naderehvandi
2008-12-17 19:56 ` Khashayar Naderehvandi
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.