[PATCH v2 4/4] [media] s5p-mfc: Always check and set 'v4l2_pix_format:field' field

[Andrzej Hajda]

On 09.02.2017 21:04, Thibault Saunier wrote:
> It is required by the standard that the field order is set by the
> driver.
>
> Signed-off-by: Thibault Saunier <thibault.saunier at osg.samsung.com>
> ---
>  drivers/media/platform/s5p-mfc/s5p_mfc_dec.c | 23 +++++++++++++++++++++--
>  1 file changed, 21 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/media/platform/s5p-mfc/s5p_mfc_dec.c b/drivers/media/platform/s5p-mfc/s5p_mfc_dec.c
> index 960d6c7052bd..309b0a1bbca5 100644
> --- a/drivers/media/platform/s5p-mfc/s5p_mfc_dec.c
> +++ b/drivers/media/platform/s5p-mfc/s5p_mfc_dec.c
> @@ -345,7 +345,6 @@ static int vidioc_g_fmt(struct file *file, void *priv, struct v4l2_format *f)
>  		   rectangle. */
>  		pix_mp->width = ctx->buf_width;
>  		pix_mp->height = ctx->buf_height;
> -		pix_mp->field = V4L2_FIELD_NONE;
>  		pix_mp->num_planes = 2;
>  		/* Set pixelformat to the format in which MFC
>  		   outputs the decoded frame */
> @@ -369,7 +368,6 @@ static int vidioc_g_fmt(struct file *file, void *priv, struct v4l2_format *f)
>  		   so width and height have no meaning */
>  		pix_mp->width = 0;
>  		pix_mp->height = 0;
> -		pix_mp->field = V4L2_FIELD_NONE;
>  		pix_mp->plane_fmt[0].bytesperline = ctx->dec_src_buf_size;
>  		pix_mp->plane_fmt[0].sizeimage = ctx->dec_src_buf_size;
>  		pix_mp->pixelformat = ctx->src_fmt->fourcc;
> @@ -379,6 +377,14 @@ static int vidioc_g_fmt(struct file *file, void *priv, struct v4l2_format *f)
>  		mfc_debug(2, "%s-- with error\n", __func__);
>  		return -EINVAL;
>  	}
> +
> +	if (pix_mp->field == V4L2_FIELD_ANY) {
> +		pix_mp->field = V4L2_FIELD_NONE;
> +	} else if (pix_mp->field != V4L2_FIELD_NONE) {
> +		mfc_err("Not supported field order(%d)\n", pix_mp->field);
> +		return -EINVAL;
> +	}
> +

Again in g_fmt you should not check current value of the field.

>  	mfc_debug_leave();
>  	return 0;
>  }
> @@ -389,6 +395,19 @@ static int vidioc_try_fmt(struct file *file, void *priv, struct v4l2_format *f)
>  	struct s5p_mfc_dev *dev = video_drvdata(file);
>  	struct v4l2_pix_format_mplane *pix_mp = &f->fmt.pix_mp;
>  	struct s5p_mfc_fmt *fmt;
> +	enum v4l2_field field;
> +
> +	field = f->fmt.pix.field;
> +	if (field == V4L2_FIELD_ANY) {
> +		field = V4L2_FIELD_NONE;
> +	} else if (V4L2_FIELD_NONE != field) {
> +		mfc_debug(2, "Not supported field order(%d)\n", pix_mp->field);
> +		return -EINVAL;
> +	}
> +
> +	/* V4L2 specification suggests the driver corrects the format struct
> +	 * if any of the dimensions is unsupported */
> +	f->fmt.pix.field = field;

According to docs [1], you should just adjust the field.

[1]:
http://hverkuil.home.xs4all.nl/spec/uapi/v4l/vidioc-g-fmt.html?highlight=g_fmt#c.VIDIOC_G_FMT

Regards
Andrzej

>  
>  	mfc_debug(2, "Type is %d\n", f->type);
>  	if (f->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) {