Re: [PATCH 8/8] media: cedrus: Add support for V4L2_DEC_CMD_FLUSH

[Hans Verkuil]

On 8/22/19 9:45 PM, Jernej Skrabec wrote:
> This command is useful for explicitly flushing last decoded frame.
> 
> Signed-off-by: Jernej Skrabec 
> ---
>  .../staging/media/sunxi/cedrus/cedrus_video.c | 34 +++
>  1 file changed, 34 insertions(+)
> 
> diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_video.c 
> b/drivers/staging/media/sunxi/cedrus/cedrus_video.c
> index 5153b2bba21e..9eae69d5741c 100644
> --- a/drivers/staging/media/sunxi/cedrus/cedrus_video.c
> +++ b/drivers/staging/media/sunxi/cedrus/cedrus_video.c
> @@ -331,6 +331,37 @@ static int cedrus_s_fmt_vid_out(struct file *file, void 
> *priv,
>   return 0;
>  }
>  
> +static int cedrus_try_decoder_cmd(struct file *file, void *fh,
> +   struct v4l2_decoder_cmd *dc)
> +{
> + if (dc->cmd != V4L2_DEC_CMD_FLUSH)
> + return -EINVAL;

You need to add this line here as well:

dc->flags = 0;

As per the decoder_cmd spec.

> +
> + return 0;
> +}
> +
> +static int cedrus_decoder_cmd(struct file *file, void *fh,
> +   struct v4l2_decoder_cmd *dc)
> +{
> + struct cedrus_ctx *ctx = cedrus_file2ctx(file);

You don't need this...

> + struct vb2_v4l2_buffer *out_vb, *cap_vb;
> + int ret;
> +
> + ret = cedrus_try_decoder_cmd(file, fh, dc);
> + if (ret < 0)
> + return ret;
> +
> + out_vb = v4l2_m2m_last_src_buf(ctx->fh.m2m_ctx);

... since you can use fh->m2m_ctx directly.

> + cap_vb = v4l2_m2m_last_dst_buf(ctx->fh.m2m_ctx);
> +
> + if (out_vb)
> + out_vb->flags &= ~V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF;
> + else if (cap_vb && cap_vb->is_held)
> + v4l2_m2m_buf_done(cap_vb, VB2_BUF_STATE_DONE);
> +
> + return 0;
> +}
> +

Both these functions should be moved to v4l2-mem2mem.c and renamed to
v4l2_m2m_ioctl_stateless_(try_)decoder_cmd.

As far as I can see they are completely generic and valid for any
stateless decoder. Which is very nice :-)

>  const struct v4l2_ioctl_ops cedrus_ioctl_ops = {
>   .vidioc_querycap= cedrus_querycap,
>  
> @@ -355,6 +386,9 @@ const struct v4l2_ioctl_ops cedrus_ioctl_ops = {
>   .vidioc_streamon= v4l2_m2m_ioctl_streamon,
>   .vidioc_streamoff   = v4l2_m2m_ioctl_streamoff,
>  
> + .vidioc_try_decoder_cmd = cedrus_try_decoder_cmd,
> + .vidioc_decoder_cmd = cedrus_decoder_cmd,
> +
>   .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
>   .vidioc_unsubscribe_event   = v4l2_event_unsubscribe,
>  };
> 

Regards,

Hans

Re: [PATCH 8/8] media: cedrus: Add support for V4L2_DEC_CMD_FLUSH

[Boris Brezillon]

On Thu, 22 Aug 2019 21:45:00 +0200
Jernej Skrabec  wrote:

> This command is useful for explicitly flushing last decoded frame.
> 
> Signed-off-by: Jernej Skrabec 

Reviewed-by: Boris Brezillon 

> ---
>  .../staging/media/sunxi/cedrus/cedrus_video.c | 34 +++
>  1 file changed, 34 insertions(+)
> 
> diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_video.c 
> b/drivers/staging/media/sunxi/cedrus/cedrus_video.c
> index 5153b2bba21e..9eae69d5741c 100644
> --- a/drivers/staging/media/sunxi/cedrus/cedrus_video.c
> +++ b/drivers/staging/media/sunxi/cedrus/cedrus_video.c
> @@ -331,6 +331,37 @@ static int cedrus_s_fmt_vid_out(struct file *file, void 
> *priv,
>   return 0;
>  }
>  
> +static int cedrus_try_decoder_cmd(struct file *file, void *fh,
> +   struct v4l2_decoder_cmd *dc)
> +{
> + if (dc->cmd != V4L2_DEC_CMD_FLUSH)
> + return -EINVAL;
> +
> + return 0;
> +}
> +
> +static int cedrus_decoder_cmd(struct file *file, void *fh,
> +   struct v4l2_decoder_cmd *dc)
> +{
> + struct cedrus_ctx *ctx = cedrus_file2ctx(file);
> + struct vb2_v4l2_buffer *out_vb, *cap_vb;
> + int ret;
> +
> + ret = cedrus_try_decoder_cmd(file, fh, dc);
> + if (ret < 0)
> + return ret;

Not directly related to this patch, but it seems most drivers
implementing ->vdioc_decoder_cmd() call ->vidioc_try_decoder_cmd()
internally to make sure the cmd is supported. Maybe something
we could automate at the v4l2-ioctl.c level.

[PATCH 8/8] media: cedrus: Add support for V4L2_DEC_CMD_FLUSH

[Jernej Skrabec]

This command is useful for explicitly flushing last decoded frame.

Signed-off-by: Jernej Skrabec 
---
 .../staging/media/sunxi/cedrus/cedrus_video.c | 34 +++
 1 file changed, 34 insertions(+)

diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_video.c 
b/drivers/staging/media/sunxi/cedrus/cedrus_video.c
index 5153b2bba21e..9eae69d5741c 100644
--- a/drivers/staging/media/sunxi/cedrus/cedrus_video.c
+++ b/drivers/staging/media/sunxi/cedrus/cedrus_video.c
@@ -331,6 +331,37 @@ static int cedrus_s_fmt_vid_out(struct file *file, void 
*priv,
return 0;
 }
 
+static int cedrus_try_decoder_cmd(struct file *file, void *fh,
+ struct v4l2_decoder_cmd *dc)
+{
+   if (dc->cmd != V4L2_DEC_CMD_FLUSH)
+   return -EINVAL;
+
+   return 0;
+}
+
+static int cedrus_decoder_cmd(struct file *file, void *fh,
+ struct v4l2_decoder_cmd *dc)
+{
+   struct cedrus_ctx *ctx = cedrus_file2ctx(file);
+   struct vb2_v4l2_buffer *out_vb, *cap_vb;
+   int ret;
+
+   ret = cedrus_try_decoder_cmd(file, fh, dc);
+   if (ret < 0)
+   return ret;
+
+   out_vb = v4l2_m2m_last_src_buf(ctx->fh.m2m_ctx);
+   cap_vb = v4l2_m2m_last_dst_buf(ctx->fh.m2m_ctx);
+
+   if (out_vb)
+   out_vb->flags &= ~V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF;
+   else if (cap_vb && cap_vb->is_held)
+   v4l2_m2m_buf_done(cap_vb, VB2_BUF_STATE_DONE);
+
+   return 0;
+}
+
 const struct v4l2_ioctl_ops cedrus_ioctl_ops = {
.vidioc_querycap= cedrus_querycap,
 
@@ -355,6 +386,9 @@ const struct v4l2_ioctl_ops cedrus_ioctl_ops = {
.vidioc_streamon= v4l2_m2m_ioctl_streamon,
.vidioc_streamoff   = v4l2_m2m_ioctl_streamoff,
 
+   .vidioc_try_decoder_cmd = cedrus_try_decoder_cmd,
+   .vidioc_decoder_cmd = cedrus_decoder_cmd,
+
.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
.vidioc_unsubscribe_event   = v4l2_event_unsubscribe,
 };
-- 
2.22.1