On 05/30/2012 04:45 PM, Lars-Peter Clausen wrote:
> On 05/30/2012 02:32 PM, Laurent Pinchart wrote:
>> [...]
>> + for (i = 0; i < (format->yuv ? 2 : 1); ++i) {
>> + obj = drm_gem_object_lookup(dev, file_priv,
>> + mode_cmd->handles[i]);
>> + if (obj == NULL) {
>> + dev_dbg(dev->dev, "GEM object %u not found\n",
>> + mode_cmd->handles[i]);
>> + ret = -ENOENT;
>> + goto error;
>> + }
>> + sfb->sobj[i] = to_shmob_gem_object(obj);
>> + }
>> +
>
> I added multi-plane support the cma fb helper functions and it seems to
> work. But all other DRM drivers seem to assume that multi-plane formats
> still only have a single buffer, while yours seems to assume that there is a
> plane for each buffer. The exception is the Exynos driver, but it added a
> new set of formats which are identical to the other formats, but use one
> buffer per plane.
>
> So I'm not sure how to implement this correctly in a generic fashion.
>
This post by Ville Syrj?l? seems to explain it quite well:
http://lists.freedesktop.org/archives/dri-devel/2012-April/021044.html
