media: amphion: decoder implement display delay enable

amphion vpu support a low latency mode,
when V4L2_CID_MPEG_VIDEO_DEC_DISPLAY_DELAY_ENABLE is enabled,
decoder can display frame immediately after it's decoded.
Only h264 is support yet.

Fixes: 6de8d628df6e ("media: amphion: add v4l2 m2m vpu decoder stateful driver")
Signed-off-by: Ming Qian <[e-mail]>
Signed-off-by: Hans Verkuil <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/platform/amphion/vdec.c

···
 	{0, 0, 0, 0},
 };
 
+static int vdec_op_s_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct vpu_inst *inst = ctrl_to_inst(ctrl);
+	struct vdec_t *vdec = inst->priv;
+	int ret = 0;
+
+	vpu_inst_lock(inst);
+	switch (ctrl->id) {
+	case V4L2_CID_MPEG_VIDEO_DEC_DISPLAY_DELAY_ENABLE:
+		vdec->params.display_delay_enable = ctrl->val;
+		break;
+	case V4L2_CID_MPEG_VIDEO_DEC_DISPLAY_DELAY:
+		vdec->params.display_delay = ctrl->val;
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	vpu_inst_unlock(inst);
+
+	return ret;
+}
+
 static const struct v4l2_ctrl_ops vdec_ctrl_ops = {
+	.s_ctrl = vdec_op_s_ctrl,
 	.g_volatile_ctrl = vpu_helper_g_volatile_ctrl,
 };
 
···
 	ret = v4l2_ctrl_handler_init(&inst->ctrl_handler, 20);
 	if (ret)
 		return ret;
+
+	v4l2_ctrl_new_std(&inst->ctrl_handler, &vdec_ctrl_ops,
+			  V4L2_CID_MPEG_VIDEO_DEC_DISPLAY_DELAY,
+			  0, 0, 1, 0);
+
+	v4l2_ctrl_new_std(&inst->ctrl_handler, &vdec_ctrl_ops,
+			  V4L2_CID_MPEG_VIDEO_DEC_DISPLAY_DELAY_ENABLE,
+			  0, 1, 1, 0);
 
 	ctrl = v4l2_ctrl_new_std(&inst->ctrl_handler, &vdec_ctrl_ops,
 				 V4L2_CID_MIN_BUFFERS_FOR_CAPTURE, 1, 32, 1, 2);

drivers/media/platform/amphion/vpu_codec.h

···
 struct vpu_decode_params {
 	u32 codec_format;
 	u32 output_format;
-	u32 b_dis_reorder;
+	u32 display_delay_enable;
+	u32 display_delay;
 	u32 b_non_frame;
 	u32 frame_count;
 	u32 end_flag;

drivers/media/platform/amphion/vpu_malone.c

···
 		hc->jpg[instance].jpg_mjpeg_interlaced = 0;
 	}
 
-	hc->codec_param[instance].disp_imm = params->b_dis_reorder ? 1 : 0;
+	hc->codec_param[instance].disp_imm = params->display_delay_enable ? 1 : 0;
+	if (malone_format != MALONE_FMT_AVC)
+		hc->codec_param[instance].disp_imm = 0;
 	hc->codec_param[instance].dbglog_enable = 0;
 	iface->dbglog_desc.level = 0;