[PATCH 02/23] drm: omapdrm: fb: Don't store format BPP for each plane

[Tomi Valkeinen]

Hi Laurent,

On 26/04/16 23:35, Laurent Pinchart wrote:
> The number of bits per pixel is identical for all planes, don't store
> multiple copies.

That's not true, as with NV12, Y has 8 bits per pixel and UV has 16 bits
per pixel. But as the subsampling is precalculated into the stride_bpp
(is it bytes or bits? bpp always confuses me =), the 'stride_bpp' ends
up being same for both planes.

To be honest, I'd rather go into more complex struct than simpler one.
The current one is already confusing, I think, and your version is too.
The main issue is that the sub_x is encoded into the stride_bpp. In
kmsxx I used this format:

{ PixelFormat::NV12, { 2, { { 8, 1, 1, }, { 8, 2, 2 } }, } },

The first number is the number of planes, and for each plane, bitspp,
xsub and ysub. It's more verbose, but (I think) easier to understand.

 Tomi

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