On 01/03/17 12:51, Thibault Saunier wrote:
> It is required by the standard that the field order is set by the
> driver, default to NONE in case any is provided, but we can basically
> accept any value provided by the userspace as we will anyway not
> be able to do any deinterlacing.
>
> In this patch we also make sure to pass the interlacing mode provided
> by userspace from the output to the capture side of the device so
> that the information is given back to userspace. This way it can
> handle it and potentially deinterlace afterward.
>
> Signed-off-by: Thibault Saunier <thibault.saunier@xxxxxxxxxxxxxxx>
>
> ---
>
> Changes in v6:
> - Pass user output field value to the capture as the device is not
> doing any deinterlacing and thus decoded content will still be
> interlaced on the output.
>
> Changes in v5:
> - Just adapt the field and never error out.
>
> Changes in v4: None
> Changes in v3:
> - Do not check values in the g_fmt functions as Andrzej explained in previous review
>
> Changes in v2:
> - Fix a silly build error that slipped in while rebasing the patches
>
> drivers/media/platform/s5p-mfc/s5p_mfc_common.h | 2 ++
> drivers/media/platform/s5p-mfc/s5p_mfc_dec.c | 6 +++++-
> 2 files changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/platform/s5p-mfc/s5p_mfc_common.h b/drivers/media/platform/s5p-mfc/s5p_mfc_common.h
> index ab23236aa942..3816a37de4bc 100644
> --- a/drivers/media/platform/s5p-mfc/s5p_mfc_common.h
> +++ b/drivers/media/platform/s5p-mfc/s5p_mfc_common.h
> @@ -652,6 +652,8 @@ struct s5p_mfc_ctx {
> size_t me_buffer_size;
> size_t tmv_buffer_size;
>
> + enum v4l2_field field;
> +
> enum v4l2_mpeg_mfc51_video_force_frame_type force_frame_type;
>
> struct list_head ref_queue;
> diff --git a/drivers/media/platform/s5p-mfc/s5p_mfc_dec.c b/drivers/media/platform/s5p-mfc/s5p_mfc_dec.c
> index 367ef8e8dbf0..6e5ca86fb331 100644
> --- a/drivers/media/platform/s5p-mfc/s5p_mfc_dec.c
> +++ b/drivers/media/platform/s5p-mfc/s5p_mfc_dec.c
> @@ -345,7 +345,7 @@ 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->field = ctx->field;
> pix_mp->num_planes = 2;
> /* Set pixelformat to the format in which MFC
> outputs the decoded frame */
> @@ -380,6 +380,9 @@ static int vidioc_try_fmt(struct file *file, void *priv, struct v4l2_format *f)
> struct s5p_mfc_dev *dev = video_drvdata(file);
> struct s5p_mfc_fmt *fmt;
>
> + if (f->fmt.pix.field == V4L2_FIELD_ANY)
> + f->fmt.pix.field = V4L2_FIELD_NONE;
> +
> mfc_debug(2, "Type is %d\n", f->type);
> if (f->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) {
> fmt = find_format(f, MFC_FMT_DEC);
> @@ -436,6 +439,7 @@ static int vidioc_s_fmt(struct file *file, void *priv, struct v4l2_format *f)
> goto out;
> } else if (f->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) {
> /* src_fmt is validated by call to vidioc_try_fmt */
> + ctx->field = f->fmt.pix.field;
Doing this means that you also allow for V4L2_FIELD_ALTERNATE. If you do that, then there
are additional requirements when you queue up buffers in that the 'field' has to be set to
TOP or BOTTOM in struct v4l2_buffer. I am sure that is a requirement for the encoder, how
this would work for a decoder I am not sure.
Also, values like V4L2_FIELD_SEQ_TB/BT would not behave well if you pass them through a
decoder.
Frankly I think the only 'reasonable' values would be FIELD_NONE, FIELD_INTERLACED and
possibly FIELD_ALTERNATE. I don't know enough about how codecs handle interlaced formats,
so I can't tell how much sense FIELD_ALTERNATE would make.
Properly supporting interlaced formats should only be done if you actually tested it and
know how it works and what exactly is supported.
Regards,
Hans
> ctx->src_fmt = find_format(f, MFC_FMT_DEC);
> ctx->codec_mode = ctx->src_fmt->codec_mode;
> mfc_debug(2, "The codec number is: %d\n", ctx->codec_mode);
>
