[PATCH v3 5/9] media: vimc: Separate closing of stream and thread

From: Kaaira Gupta
Date: Wed Aug 19 2020 - 14:05:44 EST


Make separate functions for stopping streaming of entities in path of a
particular stream and stopping thread. This is needed to ensure that
thread doesn't stop when one device stops streaming in case of multiple
streams.

Signed-off-by: Kaaira Gupta <kgupta@xxxxxxxxxxxxx>
---
.../media/test-drivers/vimc/vimc-streamer.c | 82 ++++++++++++-------
1 file changed, 52 insertions(+), 30 deletions(-)

diff --git a/drivers/media/test-drivers/vimc/vimc-streamer.c b/drivers/media/test-drivers/vimc/vimc-streamer.c
index cc40ecabe95a..6b5ea1537952 100644
--- a/drivers/media/test-drivers/vimc/vimc-streamer.c
+++ b/drivers/media/test-drivers/vimc/vimc-streamer.c
@@ -13,29 +13,59 @@
#include "vimc-streamer.h"

/**
- * vimc_streamer_pipeline_terminate - Disable stream in all ved in stream
+ * vimc_streamer_pipeline_terminate - Terminate the thread
*
- * @stream: the pointer to the stream structure with the pipeline to be
- * disabled.
+ * @stream: the pointer to the stream structure
*
- * Calls s_stream to disable the stream in each entity of the pipeline
+ * Erases values of stream struct and terminates the thread
*
*/
static void vimc_streamer_pipeline_terminate(struct vimc_stream *stream)
{
struct vimc_ent_device *ved;
- struct v4l2_subdev *sd;

while (stream->pipe_size) {
stream->pipe_size--;
ved = stream->ved_pipeline[stream->pipe_size];
stream->ved_pipeline[stream->pipe_size] = NULL;
+ }

- if (!is_media_entity_v4l2_subdev(ved->ent))
- continue;
+ kthread_stop(stream->kthread);
+ stream->kthread = NULL;
+}

- sd = media_entity_to_v4l2_subdev(ved->ent);
- v4l2_subdev_call(sd, video, s_stream, 0);
+/**
+ * vimc_streamer_stream_terminate - Disable stream in all ved in stream
+ *
+ * @ved: pointer to the ved for which stream needs to be disabled
+ *
+ * Calls s_stream to disable the stream in each entity of the stream
+ *
+ */
+static void vimc_streamer_stream_terminate(struct vimc_ent_device *ved)
+{
+ struct media_entity *entity = ved->ent;
+ struct video_device *vdev;
+ struct v4l2_subdev *sd;
+
+ while (entity) {
+ if (is_media_entity_v4l2_subdev(ved->ent)) {
+ sd = media_entity_to_v4l2_subdev(ved->ent);
+ v4l2_subdev_call(sd, video, s_stream, 0);
+ }
+ entity = vimc_get_source_entity(ved->ent);
+ if (!entity)
+ break;
+
+ if (is_media_entity_v4l2_subdev(entity)) {
+ sd = media_entity_to_v4l2_subdev(entity);
+ ved = v4l2_get_subdevdata(sd);
+ } else {
+ vdev = container_of(entity,
+ struct video_device,
+ entity);
+ ved = video_get_drvdata(vdev);
+ }
}
}

@@ -43,25 +73,25 @@ static void vimc_streamer_pipeline_terminate(struct vimc_stream *stream)
* vimc_streamer_stream_start - Starts streaming for all entities
* in a stream
*
- * @ved: the pointer to the vimc entity initializing the stream
+ * @cved: the pointer to the vimc entity initializing the stream
*
* Walks through the entity graph to call vimc_streamer_s_stream()
* to enable stream in all entities in path of a stream.
*
* Return: 0 if success, error code otherwise.
*/
-static int vimc_streamer_stream_start(struct vimc_stream *stream,
- struct vimc_ent_device *ved)
+static int vimc_streamer_stream_start(struct vimc_ent_device *cved)
{
struct media_entity *entity;
struct video_device *vdev;
struct v4l2_subdev *sd;
+ struct vimc_ent_device *ved = cved;
int stream_size = 0;
int ret = 0;

while (stream_size < VIMC_STREAMER_PIPELINE_MAX_SIZE) {
if (!ved) {
- vimc_streamer_pipeline_terminate(stream);
+ vimc_streamer_stream_terminate(cved);
return -EINVAL;
}

@@ -71,7 +101,7 @@ static int vimc_streamer_stream_start(struct vimc_stream *stream,
if (ret && ret != -ENOIOCTLCMD) {
dev_err(ved->dev, "subdev_call error %s\n",
ved->ent->name);
- vimc_streamer_pipeline_terminate(stream);
+ vimc_streamer_stream_terminate(cved);
return ret;
}
}
@@ -84,7 +114,7 @@ static int vimc_streamer_stream_start(struct vimc_stream *stream,
dev_err(ved->dev,
"first entity in the pipe '%s' is not a source\n",
ved->ent->name);
- vimc_streamer_pipeline_terminate(stream);
+ vimc_streamer_stream_terminate(cved);
pr_info ("first entry not source");
return -EPIPE;
}
@@ -104,7 +134,7 @@ static int vimc_streamer_stream_start(struct vimc_stream *stream,
stream_size++;
}

- vimc_streamer_pipeline_terminate(stream);
+ vimc_streamer_stream_terminate(cved);
return -EINVAL;
}

@@ -120,13 +150,14 @@ static int vimc_streamer_stream_start(struct vimc_stream *stream,
* Return: 0 if success, error code otherwise.
*/
static int vimc_streamer_pipeline_init(struct vimc_stream *stream,
- struct vimc_ent_device *ved)
+ struct vimc_ent_device *cved)
{
struct media_entity *entity;
struct media_device *mdev;
struct media_graph graph;
struct video_device *vdev;
struct v4l2_subdev *sd;
+ struct vimc_ent_device *ved = cved;
int ret;

entity = ved->ent;
@@ -170,6 +201,7 @@ static int vimc_streamer_pipeline_init(struct vimc_stream *stream,
}
}

+ vimc_streamer_stream_terminate(cved);
vimc_streamer_pipeline_terminate(stream);
return -EINVAL;
}
@@ -246,7 +278,7 @@ int vimc_streamer_s_stream(struct vimc_stream *stream,
if (stream->kthread)
return 0;

- ret = vimc_streamer_stream_start(stream, ved);
+ ret = vimc_streamer_stream_start(ved);
if (ret)
return ret;

@@ -260,6 +292,7 @@ int vimc_streamer_s_stream(struct vimc_stream *stream,
if (IS_ERR(stream->kthread)) {
ret = PTR_ERR(stream->kthread);
dev_err(ved->dev, "kthread_run failed with %d\n", ret);
+ vimc_streamer_stream_terminate(ved);
vimc_streamer_pipeline_terminate(stream);
stream->kthread = NULL;
return ret;
@@ -269,18 +302,7 @@ int vimc_streamer_s_stream(struct vimc_stream *stream,
if (!stream->kthread)
return 0;

- ret = kthread_stop(stream->kthread);
- /*
- * kthread_stop returns -EINTR in cases when streamon was
- * immediately followed by streamoff, and the thread didn't had
- * a chance to run. Ignore errors to stop the stream in the
- * pipeline.
- */
- if (ret)
- dev_dbg(ved->dev, "kthread_stop returned '%d'\n", ret);
-
- stream->kthread = NULL;
-
+ vimc_streamer_stream_terminate(ved);
vimc_streamer_pipeline_terminate(stream);
}

--
2.17.1