Re: [PATCH v10 08/16] v4l: mark unordered formats

From: Hans Verkuil
Date: Tue May 22 2018 - 07:00:56 EST


On 21/05/18 18:59, Ezequiel Garcia wrote:
> From: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxx>
>
> Now that we've introduced the V4L2_FMT_FLAG_UNORDERED flag,
> mark the appropriate formats.
>
> v2: Set unordered flag before calling the driver callback.
>
> Signed-off-by: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxx>
> Signed-off-by: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx>
> ---
> drivers/media/v4l2-core/v4l2-ioctl.c | 74 +++++++++++++++++++++++++++---------
> 1 file changed, 57 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> index f48c505550e0..2135ac235a96 100644
> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> @@ -1102,6 +1102,27 @@ static int v4l_enumoutput(const struct v4l2_ioctl_ops *ops,
> return ops->vidioc_enum_output(file, fh, p);
> }
>
> +static void v4l_fill_unordered_fmtdesc(struct v4l2_fmtdesc *fmt)
> +{
> + switch (fmt->pixelformat) {
> + case V4L2_PIX_FMT_MPEG:
> + case V4L2_PIX_FMT_H264:
> + case V4L2_PIX_FMT_H264_NO_SC:
> + case V4L2_PIX_FMT_H264_MVC:
> + case V4L2_PIX_FMT_H263:
> + case V4L2_PIX_FMT_MPEG1:
> + case V4L2_PIX_FMT_MPEG2:
> + case V4L2_PIX_FMT_MPEG4:
> + case V4L2_PIX_FMT_XVID:
> + case V4L2_PIX_FMT_VC1_ANNEX_G:
> + case V4L2_PIX_FMT_VC1_ANNEX_L:
> + case V4L2_PIX_FMT_VP8:
> + case V4L2_PIX_FMT_VP9:
> + case V4L2_PIX_FMT_HEVC:
> + fmt->flags |= V4L2_FMT_FLAG_UNORDERED;

Please add a break here. This prevents potential future errors if new cases
are added below this line.

> + }
> +}
> +
> static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
> {
> const unsigned sz = sizeof(fmt->description);
> @@ -1310,61 +1331,80 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
>
> if (descr)
> WARN_ON(strlcpy(fmt->description, descr, sz) >= sz);
> - fmt->flags = flags;
> + fmt->flags |= flags;
> }
>
> -static int v4l_enum_fmt(const struct v4l2_ioctl_ops *ops,
> - struct file *file, void *fh, void *arg)
> -{
> - struct v4l2_fmtdesc *p = arg;
> - int ret = check_fmt(file, p->type);
>
> - if (ret)
> - return ret;
> - ret = -EINVAL;
> +static int __vidioc_enum_fmt(const struct v4l2_ioctl_ops *ops,
> + struct v4l2_fmtdesc *p,
> + struct file *file, void *fh)
> +{
> + int ret = 0;
>
> switch (p->type) {
> case V4L2_BUF_TYPE_VIDEO_CAPTURE:
> if (unlikely(!ops->vidioc_enum_fmt_vid_cap))
> break;
> - ret = ops->vidioc_enum_fmt_vid_cap(file, fh, arg);
> + ret = ops->vidioc_enum_fmt_vid_cap(file, fh, p);
> break;
> case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
> if (unlikely(!ops->vidioc_enum_fmt_vid_cap_mplane))
> break;
> - ret = ops->vidioc_enum_fmt_vid_cap_mplane(file, fh, arg);
> + ret = ops->vidioc_enum_fmt_vid_cap_mplane(file, fh, p);
> break;
> case V4L2_BUF_TYPE_VIDEO_OVERLAY:
> if (unlikely(!ops->vidioc_enum_fmt_vid_overlay))
> break;
> - ret = ops->vidioc_enum_fmt_vid_overlay(file, fh, arg);
> + ret = ops->vidioc_enum_fmt_vid_overlay(file, fh, p);
> break;
> case V4L2_BUF_TYPE_VIDEO_OUTPUT:
> if (unlikely(!ops->vidioc_enum_fmt_vid_out))
> break;
> - ret = ops->vidioc_enum_fmt_vid_out(file, fh, arg);
> + ret = ops->vidioc_enum_fmt_vid_out(file, fh, p);
> break;
> case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
> if (unlikely(!ops->vidioc_enum_fmt_vid_out_mplane))
> break;
> - ret = ops->vidioc_enum_fmt_vid_out_mplane(file, fh, arg);
> + ret = ops->vidioc_enum_fmt_vid_out_mplane(file, fh, p);
> break;
> case V4L2_BUF_TYPE_SDR_CAPTURE:
> if (unlikely(!ops->vidioc_enum_fmt_sdr_cap))
> break;
> - ret = ops->vidioc_enum_fmt_sdr_cap(file, fh, arg);
> + ret = ops->vidioc_enum_fmt_sdr_cap(file, fh, p);
> break;
> case V4L2_BUF_TYPE_SDR_OUTPUT:
> if (unlikely(!ops->vidioc_enum_fmt_sdr_out))
> break;
> - ret = ops->vidioc_enum_fmt_sdr_out(file, fh, arg);
> + ret = ops->vidioc_enum_fmt_sdr_out(file, fh, p);
> break;
> case V4L2_BUF_TYPE_META_CAPTURE:
> if (unlikely(!ops->vidioc_enum_fmt_meta_cap))
> break;
> - ret = ops->vidioc_enum_fmt_meta_cap(file, fh, arg);
> + ret = ops->vidioc_enum_fmt_meta_cap(file, fh, p);
> break;
> }
> + return ret;
> +}
> +
> +static int v4l_enum_fmt(const struct v4l2_ioctl_ops *ops,
> + struct file *file, void *fh, void *arg)
> +{
> + struct v4l2_fmtdesc *p = arg;
> + int ret = check_fmt(file, p->type);
> +
> + if (ret)
> + return ret;
> + ret = -EINVAL;

Why set ret when it is overwritten below?

> +
> + ret = __vidioc_enum_fmt(ops, p, file, fh);
> + if (ret)
> + return ret;

Huh? Why call the driver twice? As far as I can see you can just drop
these three lines above.

Regards,

Hans

> + /*
> + * Set the unordered flag and call the driver
> + * again so it has the chance to clear the flag.
> + */
> + v4l_fill_unordered_fmtdesc(p);
> + ret = __vidioc_enum_fmt(ops, p, file, fh);
> if (ret == 0)
> v4l_fill_fmtdesc(p);
> return ret;
>