Re: [PATCH v2] DSS2: OMAPFB: Add support for switching memory

["Ville Syrjälä" <ville.syrjala@nokia.com>]

On Tue, Mar 02, 2010 at 07:36:59PM +0100, Syrjala Ville (Nokia-D/Helsinki) wrote:
> From: Ville Syrjälä <ville.syrjala@nokia.com>
> 
> Separate the memory region from the framebuffer device a little bit.
> It's now possible to select the memory region used by the framebuffer
> device using the new source_idx parameter of omapfb_plane_info. If the
> source_idx is specified it will be interpreted as an index into the
> memory regions array, if it's not specified the framebuffer's index is
> used instead. So by default each framebuffer keeps using it's own
> memory region which preserves backwards compatibility.
> 
> This allows cloning the same memory region to several overlays and yet
> each overlay can be controlled independently since they can be
> associated with separate framebuffer devices.
> 
> Signed-off-by: Ville Syrjälä <ville.syrjala@nokia.com>

Actaully scrap this one. The use_count thing makes it's somewhat too
easy to get stuck in a state where you can't change the memory size
anymore and going in via sysfs in an effort to fix it doesn't work. I
think I'll just go back to checking all the overlays and expand it to
loop over all the fb devices too. The check won't be entirely accurate
since the fb_infos can't be locked as that could easily lead to ABBA
deadlock with the fb_info lock and the region mutex, but I suppose it's
better than not being able to free/allocate memory anymore.

-- 
Ville Syrjälä