Re: [PATCH v9 07/15] v4l: mark unordered formats

From: Hans Verkuil
Date: Mon May 07 2018 - 09:46:02 EST


On 04/05/18 22:06, Ezequiel Garcia wrote:
> From: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxx>
>
> Now that we've introduced the V4L2_FMT_FLAG_UNORDERED flag,
> mark the appropriate formats.
>
> Signed-off-by: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxx>
> ---
> drivers/media/v4l2-core/v4l2-ioctl.c | 55 ++++++++++++++++++++----------------
> 1 file changed, 30 insertions(+), 25 deletions(-)
>
> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> index f48c505550e0..f75ad954a6f2 100644
> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> @@ -1260,20 +1260,6 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
> case V4L2_PIX_FMT_MJPEG: descr = "Motion-JPEG"; break;
> case V4L2_PIX_FMT_JPEG: descr = "JFIF JPEG"; break;
> case V4L2_PIX_FMT_DV: descr = "1394"; break;
> - case V4L2_PIX_FMT_MPEG: descr = "MPEG-1/2/4"; break;
> - case V4L2_PIX_FMT_H264: descr = "H.264"; break;
> - case V4L2_PIX_FMT_H264_NO_SC: descr = "H.264 (No Start Codes)"; break;
> - case V4L2_PIX_FMT_H264_MVC: descr = "H.264 MVC"; break;
> - case V4L2_PIX_FMT_H263: descr = "H.263"; break;
> - case V4L2_PIX_FMT_MPEG1: descr = "MPEG-1 ES"; break;
> - case V4L2_PIX_FMT_MPEG2: descr = "MPEG-2 ES"; break;
> - case V4L2_PIX_FMT_MPEG4: descr = "MPEG-4 part 2 ES"; break;
> - case V4L2_PIX_FMT_XVID: descr = "Xvid"; break;
> - case V4L2_PIX_FMT_VC1_ANNEX_G: descr = "VC-1 (SMPTE 412M Annex G)"; break;
> - case V4L2_PIX_FMT_VC1_ANNEX_L: descr = "VC-1 (SMPTE 412M Annex L)"; break;
> - case V4L2_PIX_FMT_VP8: descr = "VP8"; break;
> - case V4L2_PIX_FMT_VP9: descr = "VP9"; break;
> - case V4L2_PIX_FMT_HEVC: descr = "HEVC"; break; /* aka H.265 */
> case V4L2_PIX_FMT_CPIA1: descr = "GSPCA CPiA YUV"; break;
> case V4L2_PIX_FMT_WNVA: descr = "WNVA"; break;
> case V4L2_PIX_FMT_SN9C10X: descr = "GSPCA SN9C10X"; break;
> @@ -1294,17 +1280,36 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
> case V4L2_PIX_FMT_S5C_UYVY_JPG: descr = "S5C73MX interleaved UYVY/JPEG"; break;
> case V4L2_PIX_FMT_MT21C: descr = "Mediatek Compressed Format"; break;
> default:
> - WARN(1, "Unknown pixelformat 0x%08x\n", fmt->pixelformat);
> - if (fmt->description[0])
> - return;
> - flags = 0;
> - snprintf(fmt->description, sz, "%c%c%c%c%s",
> - (char)(fmt->pixelformat & 0x7f),
> - (char)((fmt->pixelformat >> 8) & 0x7f),
> - (char)((fmt->pixelformat >> 16) & 0x7f),
> - (char)((fmt->pixelformat >> 24) & 0x7f),
> - (fmt->pixelformat & (1 << 31)) ? "-BE" : "");
> - break;
> + /* Unordered formats */
> + flags = V4L2_FMT_FLAG_UNORDERED;

I realized that this is a problem since this function is called *after*
the driver. So the driver has no chance to clear this flag if it knows
that the queue is always ordered.

I think this needs to be split: first set the UNORDERED flag for the selected
formats, then call the driver, then fill in the rest.

Note that this function sets fmt->flags, this should become |=. Otherwise
the UNORDERED flag would be overwritten.

It's a bit messy, but I don't see a better approach. Except by setting the
UNORDERED flag in the drivers, but I prefer this more defensive approach
(i.e. presumed unordered, unless stated otherwise).

Regards,

Hans

> + switch (fmt->pixelformat) {
> + case V4L2_PIX_FMT_MPEG: descr = "MPEG-1/2/4"; break;
> + case V4L2_PIX_FMT_H264: descr = "H.264"; break;
> + case V4L2_PIX_FMT_H264_NO_SC: descr = "H.264 (No Start Codes)"; break;
> + case V4L2_PIX_FMT_H264_MVC: descr = "H.264 MVC"; break;
> + case V4L2_PIX_FMT_H263: descr = "H.263"; break;
> + case V4L2_PIX_FMT_MPEG1: descr = "MPEG-1 ES"; break;
> + case V4L2_PIX_FMT_MPEG2: descr = "MPEG-2 ES"; break;
> + case V4L2_PIX_FMT_MPEG4: descr = "MPEG-4 part 2 ES"; break;
> + case V4L2_PIX_FMT_XVID: descr = "Xvid"; break;
> + case V4L2_PIX_FMT_VC1_ANNEX_G: descr = "VC-1 (SMPTE 412M Annex G)"; break;
> + case V4L2_PIX_FMT_VC1_ANNEX_L: descr = "VC-1 (SMPTE 412M Annex L)"; break;
> + case V4L2_PIX_FMT_VP8: descr = "VP8"; break;
> + case V4L2_PIX_FMT_VP9: descr = "VP9"; break;
> + case V4L2_PIX_FMT_HEVC: descr = "HEVC"; break; /* aka H.265 */
> + default:
> + WARN(1, "Unknown pixelformat 0x%08x\n", fmt->pixelformat);
> + if (fmt->description[0])
> + return;
> + flags = 0;
> + snprintf(fmt->description, sz, "%c%c%c%c%s",
> + (char)(fmt->pixelformat & 0x7f),
> + (char)((fmt->pixelformat >> 8) & 0x7f),
> + (char)((fmt->pixelformat >> 16) & 0x7f),
> + (char)((fmt->pixelformat >> 24) & 0x7f),
> + (fmt->pixelformat & (1 << 31)) ? "-BE" : "");
> + break;
> + }
> }
> }
>
>