Re: [PATCH 2/3] acpi_video: Intel video is not always i915

[Alan Cox <alan@lxorguk.ukuu.org.uk>]

On Wed, 25 Apr 2012 12:31:52 +0100
Matthew Garrett <mjg59@srcf.ucam.org> wrote:

> On Wed, Apr 25, 2012 at 11:27:11AM +0100, Alan Cox wrote:
> > On Tue, 24 Apr 2012 23:30:22 +0100
> > Matthew Garrett <mjg59@srcf.ucam.org> wrote:
> > > Right now you seem to set opregion unconditionally on PVR, which seems 
> > > to be equivalent to the 0xfc check that was there before - I can 
> > > understand excluding i740, but the PVR check could be left with the gen 
> > > hardware one?
> > 
> > Not really - they are two drivers. If you build with i915 and not GMA500
> > you need the opregion for one and the acpi fallback for the other, and
> > vice versa. So we have to check both CONFIG_xxx macro sets.
> > 
> > Right now GMA500 needs the ACPI video stuff never to be enabled on some
> > machines. Until we've got full opregion support in the driver that won't
> > change.
> 
> opregion always seems to be set to 1 if is_gma_pvr() is true, which 
> means we'll now never bind the acpi video driver on PVR hardware. If 
> that's what you want, why distinguish between PVR and GEN?

Because as I said before there are two drivers involved and you may only
have one compiled into your kernel. If you have

CONFIG_DRM_GMA500=y
CONFIG_DRM_I915=n

you want the acpi stuff to autoregister even if an i915 is found, but not
if a GMA500 is found. Ditto the reverse.

Alan