linux-kernel - Re: video breaks asus-laptop display switching

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Sat, 22 Dec 2007 15:53:17 +0800
From:	Zhang Rui <rui.zhang@...el.com>
To:	Andrei Gaponenko <andrei.gaponenko@...n.ch>
Cc:	linux-kernel@...r.kernel.org, corentincj@...aif.net,
	sziwan@...rs.sourceforge.net
Subject: Re: video breaks asus-laptop display switching


On Sat, 2007-12-22 at 06:36 +0800, Andrei Gaponenko wrote:
> 
> Hi,
> 
> With 2.6.23 or newer (including 2.6.24-rc6) kernels, writing to the
> /sys/devices/platform/asus-laptop/display file does not do anything:
> 
> Cold boot to single user, then connect an external monitor
> 
> # cat  /sys/devices/platform/asus-laptop/display
> 1
> 
> OK, only the built in LCD is enabled. Try to enable
> the external monitor as well:
> 
> # echo 3 > /sys/devices/platform/asus-laptop/display
> 
> still no image on the external.
> 
> # cat  /sys/devices/platform/asus-laptop/display
> 1
> 
> Still "1", not the "3" we wrote. On the other hand if I boot with an
> external monitor attached, the "display" file always contains 3, even
> after writing 1 there, and there is image on both monitors.
> 
> In 2.6.22 I had to load asus-laptop by hand, but then display
> switching worked nicely. 
> 
> I've noticed that if I do
> 
> # rmmod video
> 
> display switching starts working again with the newer kernels.
> The "video" module was auto-loaded on my system in 2.6.22, but
> did not cause the conflict.
hmm, please "echo 1 > /proc/acpi/video/xxx/DOS" in 2.6.23 and see
if there is any difference.

Thansk,
Rui


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/