T420 /proc/acpi/ibm/video not working

classic Classic list List threaded Threaded
6 messages Options
Reply | Threaded
Open this post in threaded view
|

T420 /proc/acpi/ibm/video not working

David Woodfall
Hi

When I cat /proc/acpi/ibm/video it shows every monitor disabled, even when
int and ext are on.

Echoing anything there has no effect at all. It all worked fine in my
T42. What I would like to do is just use the video_switch command.

Is this a known problem, and is there a workaround?

--
The linux-thinkpad mailing list home page is at:
http://mailman.linux-thinkpad.org/mailman/listinfo/linux-thinkpad
Reply | Threaded
Open this post in threaded view
|

Re: T420 /proc/acpi/ibm/video not working

David Woodfall
>Hi
>
>When I cat /proc/acpi/ibm/video it shows every monitor disabled, even when
>int and ext are on.
>
>Echoing anything there has no effect at all. It all worked fine in my
>T42. What I would like to do is just use the video_switch command.
>
>Is this a known problem, and is there a workaround?

Sorry, I posted in haste. When I say 'int' and 'ext' I mean LCD and
VGA/CRT.

Output:

# cat /proc/acpi/ibm/video
status:         supported
lcd:            disabled
crt:            disabled
dvi:            disabled
auto:           disabled
commands:       lcd_enable, lcd_disable
commands:       crt_enable, crt_disable
commands:       dvi_enable, dvi_disable
commands:       auto_enable, auto_disable
commands:       video_switch, expand_toggle

Linux 3.13.5

I'm currently upgrading to last stable kernel to see if there's a
difference.

--
The linux-thinkpad mailing list home page is at:
http://mailman.linux-thinkpad.org/mailman/listinfo/linux-thinkpad
Reply | Threaded
Open this post in threaded view
|

Re: T420 /proc/acpi/ibm/video not working

Timothy Murphy-4
On Saturday 07 February 2015 12:14:45 David Woodfall wrote:

> Output:
>
> # cat /proc/acpi/ibm/video
> status:         supported
> lcd:            disabled
> crt:            disabled
> dvi:            disabled
> auto:           disabled
> commands:       lcd_enable, lcd_disable
> commands:       crt_enable, crt_disable
> commands:       dvi_enable, dvi_disable
> commands:       auto_enable, auto_disable
> commands:       video_switch, expand_toggle

I get the same output on my T520 under Fedora-21/KDE
in /proc/acpi/ibm/video.
But I have no idea what it means.
How does one give the command lcd_enable, for example,
and what effect does it have?

--
Timothy Murphy  
gayleard /at/ eircom.net
School of Mathematics, Trinity College, Dublin

--
The linux-thinkpad mailing list home page is at:
http://mailman.linux-thinkpad.org/mailman/listinfo/linux-thinkpad
Reply | Threaded
Open this post in threaded view
|

Re: T420 /proc/acpi/ibm/video not working

Jagged O'Neill
On Sun, Feb 08, 2015 at 04:46:15PM +0000, Timothy Murphy wrote:

> On Saturday 07 February 2015 12:14:45 David Woodfall wrote:
>
> > commands:       lcd_enable, lcd_disable
> > commands:       crt_enable, crt_disable
> > commands:       dvi_enable, dvi_disable
> > commands:       auto_enable, auto_disable
> > commands:       video_switch, expand_toggle
>
> I get the same output on my T520 under Fedora-21/KDE
> in /proc/acpi/ibm/video.
> But I have no idea what it means.
> How does one give the command lcd_enable, for example,
> and what effect does it have?

You echo those commands into the very same file. See
  https://www.kernel.org/doc/Documentation/laptops/thinkpad-acpi.txt
(some lines above the middle of the document).

Don't know if it's worth it, however. When I use an external display
with my TP, I prefer to let xrandr manage them.

Regards,
Jagged

--
valgrind python -c 'for i in range(1,1): print(i)' 2>&1 | grep error

--
The linux-thinkpad mailing list home page is at:
http://mailman.linux-thinkpad.org/mailman/listinfo/linux-thinkpad
Reply | Threaded
Open this post in threaded view
|

Re: T420 /proc/acpi/ibm/video not working

Henrique de Moraes Holschuh-2
In reply to this post by David Woodfall
On Sat, 07 Feb 2015, David Woodfall wrote:
> When I cat /proc/acpi/ibm/video it shows every monitor disabled, even when
> int and ext are on.
>
> Echoing anything there has no effect at all. It all worked fine in my
> T42. What I would like to do is just use the video_switch command.

Lenovo abandoned these interfaces a long time ago.

> Is this a known problem, and is there a workaround?

None. You have to use something else to video switch :-(

--
  "One disk to rule them all, One disk to find them. One disk to bring
  them all and in the darkness grind them. In the Land of Redmond
  where the shadows lie." -- The Silicon Valley Tarot
  Henrique Holschuh
--
The linux-thinkpad mailing list home page is at:
http://mailman.linux-thinkpad.org/mailman/listinfo/linux-thinkpad
Reply | Threaded
Open this post in threaded view
|

Re: T420 /proc/acpi/ibm/video not working

David Woodfall
Found how to do it with xrandr, so all is well.

Thanks for the replies

David

>On Sat, 07 Feb 2015, David Woodfall wrote:
>> When I cat /proc/acpi/ibm/video it shows every monitor disabled, even when
>> int and ext are on.
>>
>> Echoing anything there has no effect at all. It all worked fine in my
>> T42. What I would like to do is just use the video_switch command.
>
>Lenovo abandoned these interfaces a long time ago.
>
>> Is this a known problem, and is there a workaround?
>
>None. You have to use something else to video switch :-(
>
>--
>  "One disk to rule them all, One disk to find them. One disk to bring
>  them all and in the darkness grind them. In the Land of Redmond
>  where the shadows lie." -- The Silicon Valley Tarot
>  Henrique Holschuh
>--
>The linux-thinkpad mailing list home page is at:
>http://mailman.linux-thinkpad.org/mailman/listinfo/linux-thinkpad

--
+———+———+———+———+———+———+———+———+———+———+———+———+———+———+———+
|   Studioware. We provide the tools. You make the music.   |
|   http://www.studioware.org                               |
|   irc.freenode.net #studioware                            |
|   irc.oftc.net #studioware                                |
+———+———+———+———+———+———+———+———+———+———+———+———+———+———+———+
--
The linux-thinkpad mailing list home page is at:
http://mailman.linux-thinkpad.org/mailman/listinfo/linux-thinkpad