Re: [PATCH v4 33/36] media: imx: redo pixel format enumeration and negotiation

From: Steve Longerbeam
Date: Wed Feb 22 2017 - 18:53:44 EST

Hi Philipp,

On 02/16/2017 03:32 AM, Philipp Zabel wrote:
On Wed, 2017-02-15 at 18:19 -0800, Steve Longerbeam wrote:
The previous API and negotiation of mbus codes and pixel formats
was broken, and has been completely redone.

The negotiation of media bus codes should be as follows:


sink pad direct src pad IDMAC src pad
-------- ---------------- -------------
RGB (any) IPU RGB RGB (any)
YUV (any) IPU YUV YUV (any)
Bayer N/A must be same bayer code as sink

The IDMAC src pad should also use the internal 32-bit RGB / YUV format,
except if bayer/raw mode is selected, in which case the attached capture
video device should only allow a single mode corresponding to the output
pad media bus format.

The IDMAC source pad is going to memory, so it has left the IPU.
Are you sure it should be an internal IPU format? I realize it
is linked to a capture device node, and the IPU format could then
be translated to a v4l2 fourcc by the capture device, but IMHO this
pad is external to the IPU.