Re: Getting started with OMAP3 ISP

On 2011-09-01 12:14, Laurent Pinchart wrote:

Hi Enrico,

On Thursday 01 September 2011 19:24:54 Enrico wrote:

quoted

On Thu, Sep 1, 2011 at 6:14 PM, Enrico[off-list ref]  wrote:

quoted

On Thu, Sep 1, 2011 at 5:16 PM, Gary Thomas[off-list ref]  wrote:

quoted

- entity 16: tvp5150m1 2-005c (1 pad, 1 link)
             type V4L2 subdev subtype Unknown
             device node name /dev/v4l-subdev8
        pad0: Output [unknown 720x480 (1,1)/720x480]
                ->  'OMAP3 ISP CCDC':pad0 [ACTIVE]

Ideas where to look for the 'unknown' mode?

I didn't notice that, if you are using UYVY8_2X8 the reason is in
media-ctl main.c:

{ "UYVY", V4L2_MBUS_FMT_UYVY8_1X16 },

You can add a line like:

{ "UYVY2X8", V4L2_MBUS_FMT_UYVY8_2X8 },

recompile and it should work, i'll try it now.

That worked, but now there is another problem.

That's correct. My bad for not spotting it sooner.

Will you be adding this to the media-ctl tree?  Would you like a patch?

quoted

yavta will set UYVY (PIX_FMT), this will cause a call to
ispvideo.c:isp_video_pix_to_mbus(..), that will do this:

for (i = 0; i<  ARRAY_SIZE(formats); ++i) {
                 if (formats[i].pixelformat == pix->pixelformat)
                         break;
}

that is it will stop at the first matching array item, and that's:

{ V4L2_MBUS_FMT_UYVY8_1X16, V4L2_MBUS_FMT_UYVY8_1X16,
           V4L2_MBUS_FMT_UYVY8_1X16, 0,
           V4L2_PIX_FMT_UYVY, 16, 16, },


but you wanted this:

{ V4L2_MBUS_FMT_UYVY8_2X8, V4L2_MBUS_FMT_UYVY8_2X8,
           V4L2_MBUS_FMT_UYVY8_2X8, 0,
           V4L2_PIX_FMT_UYVY, 8, 16, },

so a better check could be to check for width too, but i don't know if
it's possibile to pass a width requirement or if it's already there in
some struct passed to the function.

That's not really an issue, as the isp_video_pix_to_mbus() and
isp_video_mbus_to_pix() calls in isp_video_set_format() are just used to fill
the bytesperline and sizeimage fields. From a quick look at the code
isp_video_check_format() should succeed as well.

Have you run into any specific issue with isp_video_pix_to_mbus() when using
V4L2_MBUS_FMT_UYVY8_2X8 ?

Not yet - I was able to configure the pipeline as
   # media-ctl -f '"tvp5150m1 2-005c":0[UYVY2X8 720x480], "OMAP3 ISP CCDC":0[UYVY2X8 720x480], "OMAP3 ISP CCDC":1[UYVY2X8 720x480]'
and this gets me all the way into my driver (which I'm now working on)

-- 
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Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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