[ltp] Question on X60

[Alex Deucher]

On 2/28/07, Henrique de Moraes Holschuh <hmh@hmh.eng.br> wrote:
> On Wed, 28 Feb 2007, Dieter Jurzitza wrote:
> > - X60 comes with i945 graphics.This one is apparently not detected correctly
> > by the acpi-daemon (or the ibm_acpi module)
>
> Usually ibm-acpi doesn't care at all about the video hardware.  It talks to
> the ACPI DSDT, only.
>
> > - /proc/acpi/ibm/video does not react to video_switch events as expected.
> > (echo video_switch > /proc/acpi/ibm/video) IMHO this is a bug.
>
> Not if X told the ACPI DSDT to lock down video switching, which it might
> well do.  I don't know about the intel GMA drivers, but the ATI driver can
> do that, and does it by default.  The ATI driver lets you tell it to not
> lock down the ACPI video switching.  I don't know about the intel driver.
>
> > I assume the problem is buried somewhere down in the acpi-subsystem, maybe in
> > ibm_acpi.ko; but I could not track that down until now. I think it is not
> > related to the X-server.
>
> Make extremely sure X is not masking off "bios hotkeys" or anything like
> that.  If it does, ibm-acpi commands to switch the video output will --
> *correctly* -- do nothing.
>
> Also, boot the machine in single user mode, do *NOT* let the X server start
> *at* *all*, and try ibm-acpi video switching.  Warning: may crash or do
> stupid things depending on how well the kernel framebuffer support for intel
> chips is behaving nowadays, I wouldn't know.
>

Another thing to keep in mind, newer intel chips can't drive LVDS and
VGA with the same crtc at the same time, using both outputs requires
both crtcs.  I'm not sure all bioses support this.  the optimal
solution would be to just run xrandr when you receive an acpi event.
Then the X driver can handle the events natively.  On another note,
the intel fb driver only supports VGA; it has no support for other
outputs.

Alex