[PATCH] staging: drm/omap: add rotation properties

[Rob Clark]

On Fri, Jun 29, 2012 at 5:46 AM, Tomi Valkeinen <tomi.valkeinen at ti.com> wrote:
> On Wed, 2012-06-27 at 09:06 -0500, Rob Clark wrote:
>> From: Rob Clark <rob at ti.com>
>>
>> Use tiled buffers for rotated/reflected scanout, with CRTC and plane
>> properties as the interface for userspace to configure rotation.
>>
>> Signed-off-by: Rob Clark <rob at ti.com>
>
>> +/* this should probably be in drm-core to standardize amongst drivers */
>> +#define DRM_ROTATE_0 0
>> +#define DRM_ROTATE_90        1
>> +#define DRM_ROTATE_180       2
>> +#define DRM_ROTATE_270       3
>> +#define DRM_REFLECT_X        4
>> +#define DRM_REFLECT_Y        5
>
> Are both reflect X and Y needed? You can get all the possible
> orientations with just one of the reflects.
>
> And I think the word "mirror" represents nicely what the reflect does,
> i.e. if you look at the mirror, the image you see is flipped
> horizontally.

fwiw these values are aligned with what is used in userspace xrandr..
an earlier version of this patch used just 3 bits, which where aligned
with what the omap hw uses and can describe all possible combinations
of mirroring and isomorphic rotation (x-invert, y-invert, and
xy-flip).  But the advantage of the xrandr approach is you can more
easily leave out bits for rotation/mirroring modes that your hw does
not support.. for example if some hw supports only certain rotations
or does not support mirror/reflect.

BR,
-R

>  Tomi
>