From: Milen Mitkov <quic_mmitkov@xxxxxxxxxxx>
Use the multistream series function video_device_pipeline_alloc_start
to allows multiple clients of the same pipeline.
If the VFE entity is used by another instance of the pipeline,
the pipeline won't be stopped. This allows for stopping and starting
streams at any point without disrupting the other running streams.
To prepare and start multiple virtual channels each CSID source pad
corresponding to a virtual channel must be linked to the corresponding
IFE entity. Note that on SM8250 each CSID is connected, at the
hardware level, to only one IFE. Thus, you must use CSID1 with IFE1
and you can't use it with IFE0 for example.
Example: the following media controller setup expects multiplexed
sensor data on CSIPHY2. Data will be passed on to CSID0, which will
demux it to 2 streams - for RDI0 and RD1 ports of IFE0.:
media-ctl -v -d /dev/media0 -V '"imx577 '22-001a'":0[fmt:SRGGB10/3840x2160 field:none]'
media-ctl -V '"msm_csiphy2":0[fmt:SRGGB10/3840x2160]'
media-ctl -V '"msm_csid0":0[fmt:SRGGB10/3840x2160]'
media-ctl -V '"msm_csid0":1[fmt:SRGGB10/3840x2160]'
media-ctl -V '"msm_csid0":2[fmt:SRGGB10/3840x2160]'
media-ctl -V '"msm_vfe0_rdi0":0[fmt:SRGGB10/3840x2160]'
media-ctl -V '"msm_vfe0_rdi1":0[fmt:SRGGB10/3840x2160]'
media-ctl -l '"msm_csiphy2":1->"msm_csid0":0[1]'
media-ctl -l '"msm_csid0":1->"msm_vfe0_rdi0":0[1]'
media-ctl -l '"msm_csid0":2->"msm_vfe0_rdi1":0[1]'
Note: CSID's entity pad 0 is a sink pad, pads 1..4 are source pads
To start streaming a v4l2 client must open the corresponding
/dev/videoN node. For example, with yavta:
yavta -B capture-mplane -c -I -n 5 -f SRGGB10P -s 3840x2160 -F /dev/video0
yavta -B capture-mplane -c -I -n 5 -f SRGGB10P -s 3840x2160 -F /dev/video1
Note that IFEs (vfe0, vfe1) on SM8250 have 3 RDI ports and a single
PIX port and IFELites (vfe2, vfe3) have 4 RDI ports and no PIX port.
Signed-off-by: Milen Mitkov <quic_mmitkov@xxxxxxxxxxx>
Reviewed-by: Robert Foss <robert.foss@xxxxxxxxxx>
Tested-by: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxxx>
Acked-by: Robert Foss <robert.foss@xxxxxxxxxx>
---
.../media/platform/qcom/camss/camss-video.c | 21 ++++++++++++++++---
1 file changed, 18 insertions(+), 3 deletions(-)
diff --git a/drivers/media/platform/qcom/camss/camss-video.c b/drivers/media/platform/qcom/camss/camss-video.c
index 41deda232e4a..12ac7d4d755e 100644
--- a/drivers/media/platform/qcom/camss/camss-video.c
+++ b/drivers/media/platform/qcom/camss/camss-video.c
@@ -351,6 +351,7 @@ static int video_get_subdev_format(struct camss_video *video,
if (subdev == NULL)
return -EPIPE;
+ memset(&fmt, 0, sizeof(fmt));
fmt.pad = pad;
fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
@@ -493,9 +494,11 @@ static int video_start_streaming(struct vb2_queue *q, unsigned int count)
struct v4l2_subdev *subdev;
int ret;
- ret = video_device_pipeline_start(vdev, &video->pipe);
- if (ret < 0)
+ ret = video_device_pipeline_alloc_start(vdev);
+ if (ret < 0) {
+ dev_err(video->camss->dev, "Failed to start media pipeline: %d\n", ret);
goto flush_buffers;
+ }
ret = video_check_format(video);
if (ret < 0)
@@ -537,6 +540,7 @@ static void video_stop_streaming(struct vb2_queue *q)
struct media_entity *entity;
struct media_pad *pad;
struct v4l2_subdev *subdev;
+ int ret;
entity = &vdev->entity;
while (1) {
@@ -551,7 +555,18 @@ static void video_stop_streaming(struct vb2_queue *q)
entity = pad->entity;
subdev = media_entity_to_v4l2_subdev(entity);
- v4l2_subdev_call(subdev, video, s_stream, 0);
+ ret = v4l2_subdev_call(subdev, video, s_stream, 0);
+
+ if (entity->use_count > 1) {
+ /* Don't stop if other instances of the pipeline are still running */
+ dev_dbg(video->camss->dev, "Video pipeline still used, don't stop streaming.\n");
+ return;
+ }
+
+ if (ret) {
+ dev_err(video->camss->dev, "Video pipeline stop failed: %d\n", ret);
+ return;
+ }
}
video_device_pipeline_stop(vdev);
--
2.37.3
