[PATCH RFC] media: hantro: Implement support for encoder commands

[Chen-Yu Tsai]

On Tue, Feb 8, 2022 at 6:55 PM Chen-Yu Tsai <wenst at chromium.org> wrote:
>
> The V4L2 stateful encoder uAPI specification requires that drivers
> support the ENCODER_CMD ioctl to allow draining of buffers. This
> however was not implemented, and causes issues for some userspace
> applications.
>
> Implement support for the ENCODER_CMD ioctl using v4l2-mem2mem helpers.
> This is entirely based on existing code found in the vicodec test
> driver.
>
> Fixes: 775fec69008d ("media: add Rockchip VPU JPEG encoder driver")
> Signed-off-by: Chen-Yu Tsai <wenst at chromium.org>
> ---
>
> This is based on linux-next-20220207, and was tested on RK3399 with
> Gstreamer running the JPEG encoder. It was also tested on ChromeOS
> 5.10 on Kevin with the video encoder used in ChromeOS ARC, which
> requires this.
>
> Everything works OK, but since I'm not very familiar with the mem2mem
> framework, I might be missing something, causing resource leaks.
> Hence this patch is labeled RFC.

And it seems I failed to handle the case where the last capture buffer
is empty.

Will rework and send a new version tomorrow.


ChenYu

> ---
>  drivers/staging/media/hantro/hantro_drv.c  | 10 +++++
>  drivers/staging/media/hantro/hantro_v4l2.c | 44 ++++++++++++++++++++++
>  2 files changed, 54 insertions(+)
>
> diff --git a/drivers/staging/media/hantro/hantro_drv.c b/drivers/staging/media/hantro/hantro_drv.c
> index bc9bcb4eaf46..ccd47eee5c43 100644
> --- a/drivers/staging/media/hantro/hantro_drv.c
> +++ b/drivers/staging/media/hantro/hantro_drv.c
> @@ -56,6 +56,10 @@ dma_addr_t hantro_get_ref(struct hantro_ctx *ctx, u64 ts)
>         return hantro_get_dec_buf_addr(ctx, buf);
>  }
>
> +static const struct v4l2_event hantro_eos_event = {
> +       .type = V4L2_EVENT_EOS
> +};
> +
>  static void hantro_job_finish_no_pm(struct hantro_dev *vpu,
>                                     struct hantro_ctx *ctx,
>                                     enum vb2_buffer_state result)
> @@ -73,6 +77,12 @@ static void hantro_job_finish_no_pm(struct hantro_dev *vpu,
>         src->sequence = ctx->sequence_out++;
>         dst->sequence = ctx->sequence_cap++;
>
> +       if (v4l2_m2m_is_last_draining_src_buf(ctx->fh.m2m_ctx, src)) {
> +               dst->flags |= V4L2_BUF_FLAG_LAST;
> +               v4l2_event_queue_fh(&ctx->fh, &hantro_eos_event);
> +               v4l2_m2m_mark_stopped(ctx->fh.m2m_ctx);
> +       }
> +
>         v4l2_m2m_buf_done_and_job_finish(ctx->dev->m2m_dev, ctx->fh.m2m_ctx,
>                                          result);
>  }
> diff --git a/drivers/staging/media/hantro/hantro_v4l2.c b/drivers/staging/media/hantro/hantro_v4l2.c
> index 67148ba346f5..8c6746637236 100644
> --- a/drivers/staging/media/hantro/hantro_v4l2.c
> +++ b/drivers/staging/media/hantro/hantro_v4l2.c
> @@ -628,6 +628,39 @@ static int vidioc_s_selection(struct file *file, void *priv,
>         return 0;
>  }
>
> +static const struct v4l2_event hantro_eos_event = {
> +       .type = V4L2_EVENT_EOS
> +};
> +
> +static int vidioc_encoder_cmd(struct file *file, void *priv,
> +                             struct v4l2_encoder_cmd *ec)
> +{
> +       struct hantro_ctx *ctx = fh_to_ctx(priv);
> +       int ret;
> +
> +       ret = v4l2_m2m_ioctl_try_encoder_cmd(file, priv, ec);
> +       if (ret < 0)
> +               return ret;
> +
> +       if (!vb2_is_streaming(v4l2_m2m_get_src_vq(ctx->fh.m2m_ctx)) ||
> +           !vb2_is_streaming(v4l2_m2m_get_dst_vq(ctx->fh.m2m_ctx)))
> +               return 0;
> +
> +       ret = v4l2_m2m_ioctl_encoder_cmd(file, priv, ec);
> +       if (ret < 0)
> +               return ret;
> +
> +       if (ec->cmd == V4L2_ENC_CMD_STOP &&
> +           v4l2_m2m_has_stopped(ctx->fh.m2m_ctx))
> +               v4l2_event_queue_fh(&ctx->fh, &hantro_eos_event);
> +
> +       if (ec->cmd == V4L2_ENC_CMD_START &&
> +           v4l2_m2m_has_stopped(ctx->fh.m2m_ctx))
> +               vb2_clear_last_buffer_dequeued(&ctx->fh.m2m_ctx->cap_q_ctx.q);
> +
> +       return 0;
> +}
> +
>  const struct v4l2_ioctl_ops hantro_ioctl_ops = {
>         .vidioc_querycap = vidioc_querycap,
>         .vidioc_enum_framesizes = vidioc_enum_framesizes,
> @@ -657,6 +690,9 @@ const struct v4l2_ioctl_ops hantro_ioctl_ops = {
>
>         .vidioc_g_selection = vidioc_g_selection,
>         .vidioc_s_selection = vidioc_s_selection,
> +
> +       .vidioc_try_encoder_cmd = v4l2_m2m_ioctl_try_encoder_cmd,
> +       .vidioc_encoder_cmd = vidioc_encoder_cmd,
>  };
>
>  static int
> @@ -759,6 +795,8 @@ static int hantro_start_streaming(struct vb2_queue *q, unsigned int count)
>         struct hantro_ctx *ctx = vb2_get_drv_priv(q);
>         int ret = 0;
>
> +       v4l2_m2m_update_start_streaming_state(ctx->fh.m2m_ctx, q);
> +
>         if (V4L2_TYPE_IS_OUTPUT(q->type))
>                 ctx->sequence_out = 0;
>         else
> @@ -831,6 +869,12 @@ static void hantro_stop_streaming(struct vb2_queue *q)
>                 hantro_return_bufs(q, v4l2_m2m_src_buf_remove);
>         else
>                 hantro_return_bufs(q, v4l2_m2m_dst_buf_remove);
> +
> +       v4l2_m2m_update_stop_streaming_state(ctx->fh.m2m_ctx, q);
> +
> +       if (V4L2_TYPE_IS_OUTPUT(q->type) &&
> +           v4l2_m2m_has_stopped(ctx->fh.m2m_ctx))
> +               v4l2_event_queue_fh(&ctx->fh, &hantro_eos_event);
>  }
>
>  static void hantro_buf_request_complete(struct vb2_buffer *vb)
> --
> 2.35.0.263.gb82422642f-goog
>