Re: [PATCH v2] venus: venc: add handling for VIDIOC_ENCODER_CMD

[Nicolas Dufresne]

Hi Dikshita,

Le vendredi 23 décembre 2022 à 15:46 +0530, Dikshita Agarwal a écrit :
> Add handling for below commands in encoder:
> 1. V4L2_ENC_CMD_STOP
> 2. V4L2_ENC_CMD_START
> 
> Signed-off-by: Dikshita Agarwal <quic_dikshita@xxxxxxxxxxx>
> ---
>  drivers/media/platform/qcom/venus/core.h |  9 +++++
>  drivers/media/platform/qcom/venus/venc.c | 63 ++++++++++++++++++++++++++++++++
>  2 files changed, 72 insertions(+)
> 
> diff --git a/drivers/media/platform/qcom/venus/core.h b/drivers/media/platform/qcom/venus/core.h
> index 32551c2..d147154 100644
> --- a/drivers/media/platform/qcom/venus/core.h
> +++ b/drivers/media/platform/qcom/venus/core.h
> @@ -317,6 +317,14 @@ enum venus_dec_state {
>  	VENUS_DEC_STATE_DRC		= 7,
>  };
>  
> +enum venus_enc_state {
> +	VENUS_ENC_STATE_DEINIT		= 0,
> +	VENUS_ENC_STATE_INIT		= 1,
> +	VENUS_ENC_STATE_ENCODING	= 2,
> +	VENUS_ENC_STATE_STOPPED		= 3,
> +	VENUS_ENC_STATE_DRAIN		= 4,
> +};
> +
>  struct venus_ts_metadata {
>  	bool used;
>  	u64 ts_ns;
> @@ -428,6 +436,7 @@ struct venus_inst {
>  	u8 quantization;
>  	u8 xfer_func;
>  	enum venus_dec_state codec_state;
> +	enum venus_enc_state enc_state;
>  	wait_queue_head_t reconf_wait;
>  	unsigned int subscriptions;
>  	int buf_count;
> diff --git a/drivers/media/platform/qcom/venus/venc.c b/drivers/media/platform/qcom/venus/venc.c
> index cdb1254..a7804b0 100644
> --- a/drivers/media/platform/qcom/venus/venc.c
> +++ b/drivers/media/platform/qcom/venus/venc.c
> @@ -520,6 +520,46 @@ static int venc_subscribe_event(struct v4l2_fh *fh,
>  	}
>  }
>  
> +static int
> +venc_encoder_cmd(struct file *file, void *fh, struct v4l2_encoder_cmd *cmd)
> +{
> +	struct venus_inst *inst = to_inst(file);
> +	struct hfi_frame_data fdata = {0};
> +	int ret = 0;
> +
> +	ret = v4l2_m2m_ioctl_try_encoder_cmd(file, fh, cmd);
> +	if (ret)
> +		return ret;
> +
> +	mutex_lock(&inst->lock);
> +
> +	if (cmd->cmd == V4L2_ENC_CMD_STOP &&
> +	    inst->enc_state == VENUS_ENC_STATE_ENCODING) {
> +		/*
> +		 * Implement V4L2_ENC_CMD_STOP by enqueue an empty buffer on
> +		 * encoder input to signal EOS.
> +		 */
> +		if (!(inst->streamon_out && inst->streamon_cap))
> +			goto unlock;
> +
> +		fdata.buffer_type = HFI_BUFFER_INPUT;
> +		fdata.flags |= HFI_BUFFERFLAG_EOS;
> +		fdata.device_addr = 0xdeadb000;
> +
> +		ret = hfi_session_process_buf(inst, &fdata);
> +
> +		inst->enc_state = VENUS_ENC_STATE_DRAIN;
> +	} else if (cmd->cmd == V4L2_ENC_CMD_START &&
> +		inst->enc_state == VENUS_ENC_STATE_STOPPED) {
> +		vb2_clear_last_buffer_dequeued(&inst->fh.m2m_ctx->cap_q_ctx.q);
> +		inst->enc_state = VENUS_ENC_STATE_ENCODING;
> +	}
> +
> +unlock:
> +	mutex_unlock(&inst->lock);
> +	return ret;

I think you are missing a return value case. I would expect the driver to return
EBUSY (or something similar) if we call START while in VENUS_ENC_STATE_DRAIN
here. I suspect the case of calling STOP while in DRAIN or STOPPED state is fine
though, I'll leave it to you to analyse further.

regards,
Nicolas

> +}
> +
>  static const struct v4l2_ioctl_ops venc_ioctl_ops = {
>  	.vidioc_querycap = venc_querycap,
>  	.vidioc_enum_fmt_vid_cap = venc_enum_fmt,
> @@ -548,6 +588,7 @@ static const struct v4l2_ioctl_ops venc_ioctl_ops = {
>  	.vidioc_subscribe_event = venc_subscribe_event,
>  	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
>  	.vidioc_try_encoder_cmd = v4l2_m2m_ioctl_try_encoder_cmd,
> +	.vidioc_encoder_cmd = venc_encoder_cmd,
>  };
>  
>  static int venc_pm_get(struct venus_inst *inst)
> @@ -1196,6 +1237,8 @@ static int venc_start_streaming(struct vb2_queue *q, unsigned int count)
>  	if (ret)
>  		goto error;
>  
> +	inst->enc_state = VENUS_ENC_STATE_ENCODING;
> +
>  	mutex_unlock(&inst->lock);
>  
>  	return 0;
> @@ -1215,10 +1258,21 @@ static int venc_start_streaming(struct vb2_queue *q, unsigned int count)
>  static void venc_vb2_buf_queue(struct vb2_buffer *vb)
>  {
>  	struct venus_inst *inst = vb2_get_drv_priv(vb->vb2_queue);
> +	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
>  
>  	venc_pm_get_put(inst);
>  
>  	mutex_lock(&inst->lock);
> +
> +	if (inst->enc_state == VENUS_ENC_STATE_STOPPED) {
> +		vbuf->sequence = inst->sequence_cap++;
> +		vbuf->field = V4L2_FIELD_NONE;
> +		vb2_set_plane_payload(vb, 0, 0);
> +		v4l2_m2m_buf_done(vbuf, VB2_BUF_STATE_DONE);
> +		mutex_unlock(&inst->lock);
> +		return;
> +	}
> +
>  	venus_helper_vb2_buf_queue(vb);
>  	mutex_unlock(&inst->lock);
>  }
> @@ -1260,6 +1314,10 @@ static void venc_buf_done(struct venus_inst *inst, unsigned int buf_type,
>  		vb->planes[0].data_offset = data_offset;
>  		vb->timestamp = timestamp_us * NSEC_PER_USEC;
>  		vbuf->sequence = inst->sequence_cap++;
> +		if ((vbuf->flags & V4L2_BUF_FLAG_LAST) &&
> +		    inst->enc_state == VENUS_ENC_STATE_DRAIN) {
> +			inst->enc_state = VENUS_ENC_STATE_STOPPED;
> +		}
>  	} else {
>  		vbuf->sequence = inst->sequence_out++;
>  	}
> @@ -1362,6 +1420,9 @@ static int venc_open(struct file *file)
>  	inst->core_acquired = false;
>  	inst->nonblock = file->f_flags & O_NONBLOCK;
>  
> +	if (inst->enc_state == VENUS_ENC_STATE_DEINIT)
> +		inst->enc_state = VENUS_ENC_STATE_INIT;
> +
>  	venus_helper_init_instance(inst);
>  
>  	ret = venc_ctrl_init(inst);
> @@ -1424,6 +1485,8 @@ static int venc_close(struct file *file)
>  	v4l2_fh_del(&inst->fh);
>  	v4l2_fh_exit(&inst->fh);
>  
> +	inst->enc_state = VENUS_ENC_STATE_DEINIT;
> +
>  	venc_pm_put(inst, false);
>  
>  	kfree(inst);