[PATCH 1/2] drm: allow drivers to provide their own EDID fetching routine

[Dave Airlie]

On Tue, 2010-07-20 at 16:05 -0700, Jesse Barnes wrote:
> On Wed, 21 Jul 2010 08:54:30 +1000
> Dave Airlie <airlied at redhat.com> wrote:
> 
> > On Tue, 2010-07-20 at 15:44 -0700, Jesse Barnes wrote:
> > > Make drm_edid_read take a new argument, edid_read, to allow drivers to
> > > provide their own EDID fetch routine.  Export the bit banging DDC over
> > > i2c version of the EDID fetching routine and make the drivers use it.
> > > This sets the stage for GMBUS support in the Intel driver.
> > > 
> > 
> > I think this needs some rework.
> > 
> > You might want to checkout what the radeon driver does for hw i2c
> > engine. You should set up your own i2c hw handlers and use those instead
> > of bypassing the i2c stack. GMBUS is just another i2c hw block.
> 
> I'll check it out, but I don't see what using the i2c stack buys us
> here except for obfuscation...
> 

You'll want to use GMBUS for SDVO at some point in the future, or
something else, or you'll want to expose it to userspace for DDC/CI
users. Lots of reasons, its not obfuscation at all, what you are doing
is dodgy shortcuts.

Dave.