Problem with video output switching

2007-05-11T14:39:19Z

Frederik: /* Problems with ATI chipsets */

==Affected Models==
*ThinkPad {{T40}}, {{T40p}}, {{T41}}, {{T41p}}, {{T42}}, {{T42p}}, {{T43}}, {{T43p}}
*ThinkPad {{X22}}, {{X23}}, {{X31}}, {{X41}}, {{X60s}}

==Problem Description==
It is not possible, using the FN-F7 key, to switch between the LCD and the external monitor in the following way
LCD --> external Monitor--> both -->LCD
however ''cloning'' is possible for the Intel chipsets, see below.

===Problems with Intel chipsets===
Disabling the internal LCD (e.g. when using an external Monitor) doesn't seem to work reliably.

* For Xorg 7.022 one can clone the LCD display to an external monitor, adding the following lines to the Device section in the xorg.conf file:
Section "Device"
Identifier "Generic Video Card"
Driver "i810"
Option "Clone" "true"
Option "MonitorLayout" "CRT,LFP"
however you can not switch between these screens as described above, once you use FN-F7 the cloned display is lost.

* i810switch doesn't have any effect. After disabling the LCD it is still on (but the status display of i810switch claims that is is switched off).

* The following works with Fedora Core 6 on an {{X60s}}: i810switch 0.6.5 with the patch found on http://thpinfo.com/2006/patches/i810switch_macbook_support.patch can switch between LCD and CRT (and initially CRT is off) (NOTE: The first hunk of this patch does not apply to the source, just remove it, it is unnecessary). This patch makes i810switch recognize the i915 chipset. It should thus be doable to use this with an ACPI event/action to do {{key|Fn}}{{key|F7}} switching. After installing i810switch and its i810rotate script and the missing [[ibm-acpi]] kernel module I did the following to achieve just that:

In /etc/rc.local:
modprobe ibm_acpi
echo enable,0x084c > /proc/acpi/ibm/hotkey

in /etc/acpi/events/videoswitch.conf:
event=ibm/hotkey HKEY 00000080 00001007
action=/etc/acpi/actions/video-rotate.sh

in /etc/acpi/actions/video-rotate.sh
#!/bin/bash
exec /usr/sbin/i810rotate

* i855crt works see: http://stefan.desire.ch/howto/x41debian/#graphics for details.

* With [[ibm-acpi]], {{cmdroot|echo lcd_disable >/proc/acpi/ibm/video}} works, but {{cmdroot|echo lcd_enable >/proc/acpi/ibm/video}} doesn't work - so one can't enable it anymore after disabling it. (the strange thing is that when switching to a console with {{key|ctrl}}{{key|alt}}{{key|F1}} the LCD display is used for it, so there must be some way to enable it but I can't find out how to control this in X). I've tried this with version 0.8 and version 0.11 of [[ibm-acpi]].
** {{key|Fn}}{{key|F7}} lets me enable the internal LCD after I disabled it with {{cmdroot|echo lcd_disable >/proc/acpi/ibm/video}} on my X41 but it corrupts the crt out

===Problems with ATI chipsets===
*It is a [http://bugs.freedesktop.org/show_bug.cgi?id=2000 known issue] of xorgs radeon driver that {{key|Fn}}{{key|F7}} doesn't work.

You can force the <tt>radeon</tt> driver to enable both CRT and LCD using <tt>Option "MonitorLayout" "LVDS,CRT"</tt> in the <tt>"Device"</tt> section of {{path|/etc/X11/xorg.conf}}. The analogous option for [[fglrx]] is <tt>Option "ForceMonitors" "lvds,crt1"</tt>

The {{cmdroot|radeontool light off}} and {{cmdroot|radeontool dac off}} commands will disable the LCD and CRT if they're been enabled before in the X server, but the corresponding {{cmdroot|radeontool light on}} and {{cmdroot|radeontool dac on}} will not work if the displays have were not enabled when the X server started. Also note that turing off the CRT using this command will not reduce power consumption, nor allow [[fglrx]] to enable power saving modes.

You might try the following: Hit Ctrl+Alt+F1 to switch to a console, hit Fn+F7 to switch video, hit Alt+F7 to switch back to X.

* Similar problems exist with XFree86 4.3 and its radeon driver

You '''can''' switch the display off after switching to tty1 (STRG+ALT+F1) by
* pressing FN+F7 or
* executing ''echo crt_disable > /proc/acpi/ibm/video'' as root

You '''cannot''' do this under X11. The display is always on under X11. I tried
* ''echo auto_disable > /proc/acpi/ibm/video''
* ''echo crt_disable > /proc/acpi/ibm/video''
* ''echo lcd_disable > /proc/acpi/ibm/video''
* pressing FN+F7

but none of the above had any effect. If you switch the display off, then start X or switch to it, the display
will be activated automatically.

====fglrx-Driver====
Output switching with the Closed-Source ati-driver works: Just use {{cmdroot|aticonfig --query-monitor}} and e.g. {{cmdroot |aticonfig --enable-monitor..."}}. You can use those two commands in a script, and bind them to {{key|Fn}}{{key|F7}}

----

Alternative solution: {{path|fglrx}} 8.28.8 will recognize {{key|Fn}}{{key|F7}} directly, if the key is enabled. This obviates the need for scripts which call aticonfig. To enable the hotkey, issue the command {{cmdroot|echo enable,0xffff >/proc/acpi/ibm/hotkey}}. You'll want to have this run both at boot time, and after resume (on my T43, the hotkey mask is reset on resume). For Ubuntu, I've put a script with the command in both the {{path|/etc/acpi/resume.d}}, and {{path|/etc/acpi/start.d}} directories.

====VESA driver====

I have fixed the problem on my T42 by switching to the generic VESA driver in xorg.conf, and rebooting, as mentioned on the xorg bug page above. None of the other solutions worked.

==Related Links==
*https://bugs.freedesktop.org/show_bug.cgi?id=2000

==Solutions==

====BIOSHotKeys====

Try adding
Option "BiosHotKeys" "on"
to "Device" selection in /etc/xorg.conf. For some reason, this is not the default, and will cause xorg to ignore the BIOS's request to switch modes!
This fixes the problem for an X22, with xorg 6.9.0.

It fixed this problem for a X31 with xorg 7.1.1 too, but as the CRT is the primary display in some Thinkpads (like in the X31), you can not switch back to the LCD (or both) if xorg has started with the CRT only or both mode, because it sets the resolution and or refresrate to high for the LCD.

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Problem with video output switching