@@ -169,8 +169,11 @@ Drivers initiate a graph traversal by calling
The graph structure, provided by the caller, is initialized to start graph
traversal at the given pad in an entity.
-Drivers can then retrieve the next entity by calling
-:c:func:`media_graph_walk_next()`
+Drivers can then retrieve the next pad by calling
+:c:func:`media_graph_walk_next()`. Only the pad through which the entity
+is first reached is returned. If the caller is interested in knowing which
+further pads would be connected, the :c:func:`media_entity_has_route()`
+function can be used for that.
When the graph traversal is complete the function will return ``NULL``.
@@ -340,9 +340,9 @@ static void media_graph_walk_iter(struct media_graph *graph)
next->entity->name, next->index);
}
-struct media_entity *media_graph_walk_next(struct media_graph *graph)
+struct media_pad *media_graph_walk_next(struct media_graph *graph)
{
- struct media_entity *entity;
+ struct media_pad *pad;
if (stack_top(graph) == NULL)
return NULL;
@@ -355,11 +355,11 @@ struct media_entity *media_graph_walk_next(struct media_graph *graph)
while (link_top(graph) != &stack_top(graph)->entity->links)
media_graph_walk_iter(graph);
- entity = stack_pop(graph)->entity;
- dev_dbg(entity->graph_obj.mdev->dev,
- "walk: returning entity '%s'\n", entity->name);
+ pad = stack_pop(graph);
+ dev_dbg(pad->graph_obj.mdev->dev,
+ "walk: returning pad '%s':%u\n", pad->entity->name, pad->index);
- return entity;
+ return pad;
}
EXPORT_SYMBOL_GPL(media_graph_walk_next);
@@ -407,7 +407,8 @@ __must_check int __media_pipeline_start(struct media_entity *entity,
{
struct media_device *mdev = entity->graph_obj.mdev;
struct media_graph *graph = &pipe->graph;
- struct media_entity *entity_err = entity;
+ struct media_pad *pad = entity->pads;
+ struct media_pad *pad_err = pad;
struct media_link *link;
int ret;
@@ -417,9 +418,11 @@ __must_check int __media_pipeline_start(struct media_entity *entity,
goto error_graph_walk_start;
}
- media_graph_walk_start(&pipe->graph, entity->pads);
+ media_graph_walk_start(&pipe->graph, pad);
+
+ while ((pad = media_graph_walk_next(graph))) {
+ struct media_entity *entity = pad->entity;
- while ((entity = media_graph_walk_next(graph))) {
DECLARE_BITMAP(active, MEDIA_ENTITY_MAX_PADS);
DECLARE_BITMAP(has_no_links, MEDIA_ENTITY_MAX_PADS);
@@ -428,7 +431,7 @@ __must_check int __media_pipeline_start(struct media_entity *entity,
if (entity->pipe && entity->pipe != pipe) {
pr_err("Pipe active for %s. Can't start for %s\n",
entity->name,
- entity_err->name);
+ pad_err->entity->name);
ret = -EBUSY;
goto error;
}
@@ -446,26 +449,27 @@ __must_check int __media_pipeline_start(struct media_entity *entity,
bitmap_fill(has_no_links, entity->num_pads);
list_for_each_entry(link, &entity->links, list) {
- struct media_pad *pad = link->sink->entity == entity
- ? link->sink : link->source;
+ struct media_pad *other_pad =
+ link->sink->entity == entity ?
+ link->sink : link->source;
/* Mark that a pad is connected by a link. */
- bitmap_clear(has_no_links, pad->index, 1);
+ bitmap_clear(has_no_links, other_pad->index, 1);
/*
* Pads that either do not need to connect or
* are connected through an enabled link are
* fine.
*/
- if (!(pad->flags & MEDIA_PAD_FL_MUST_CONNECT) ||
+ if (!(other_pad->flags & MEDIA_PAD_FL_MUST_CONNECT) ||
link->flags & MEDIA_LNK_FL_ENABLED)
- bitmap_set(active, pad->index, 1);
+ bitmap_set(active, other_pad->index, 1);
/*
* Link validation will only take place for
* sink ends of the link that are enabled.
*/
- if (link->sink != pad ||
+ if (link->sink != other_pad ||
!(link->flags & MEDIA_LNK_FL_ENABLED))
continue;
@@ -501,9 +505,11 @@ __must_check int __media_pipeline_start(struct media_entity *entity,
* Link validation on graph failed. We revert what we did and
* return the error.
*/
- media_graph_walk_start(graph, entity_err->pads);
+ media_graph_walk_start(graph, pad_err);
+
+ while ((pad_err = media_graph_walk_next(graph))) {
+ struct media_entity *entity_err = pad_err->entity;
- while ((entity_err = media_graph_walk_next(graph))) {
/* Sanity check for negative stream_count */
if (!WARN_ON_ONCE(entity_err->stream_count <= 0)) {
entity_err->stream_count--;
@@ -515,7 +521,7 @@ __must_check int __media_pipeline_start(struct media_entity *entity,
* We haven't increased stream_count further than this
* so we quit here.
*/
- if (entity_err == entity)
+ if (pad_err == pad)
break;
}
@@ -542,8 +548,9 @@ EXPORT_SYMBOL_GPL(media_pipeline_start);
void __media_pipeline_stop(struct media_entity *entity)
{
- struct media_graph *graph = &entity->pipe->graph;
struct media_pipeline *pipe = entity->pipe;
+ struct media_graph *graph = &pipe->graph;
+ struct media_pad *pad;
/*
* If the following check fails, the driver has performed an
@@ -554,7 +561,9 @@ void __media_pipeline_stop(struct media_entity *entity)
media_graph_walk_start(graph, entity->pads);
- while ((entity = media_graph_walk_next(graph))) {
+ while ((pad = media_graph_walk_next(graph))) {
+ struct media_entity *entity = pad->entity;
+
/* Sanity check for negative stream_count */
if (!WARN_ON_ONCE(entity->stream_count <= 0)) {
entity->stream_count--;
@@ -1166,7 +1166,7 @@ static int __fimc_md_modify_pipeline(struct media_entity *entity, bool enable)
static int __fimc_md_modify_pipelines(struct media_entity *entity, bool enable,
struct media_graph *graph)
{
- struct media_entity *entity_err = entity;
+ struct media_pad *pad, *pad_err = entity->pads;
int ret;
/*
@@ -1175,13 +1175,13 @@ static int __fimc_md_modify_pipelines(struct media_entity *entity, bool enable,
* through active links. This is needed as we cannot power on/off the
* subdevs in random order.
*/
- media_graph_walk_start(graph, entity->pads);
+ media_graph_walk_start(graph, pad_err);
- while ((entity = media_graph_walk_next(graph))) {
- if (!is_media_entity_v4l2_video_device(entity))
+ while ((pad = media_graph_walk_next(graph))) {
+ if (!is_media_entity_v4l2_video_device(pad->entity))
continue;
- ret = __fimc_md_modify_pipeline(entity, enable);
+ ret = __fimc_md_modify_pipeline(pad->entity, enable);
if (ret < 0)
goto err;
@@ -1190,15 +1190,15 @@ static int __fimc_md_modify_pipelines(struct media_entity *entity, bool enable,
return 0;
err:
- media_graph_walk_start(graph, entity_err->pads);
+ media_graph_walk_start(graph, pad_err);
- while ((entity_err = media_graph_walk_next(graph))) {
- if (!is_media_entity_v4l2_video_device(entity_err))
+ while ((pad_err = media_graph_walk_next(graph))) {
+ if (!is_media_entity_v4l2_video_device(pad_err->entity))
continue;
- __fimc_md_modify_pipeline(entity_err, !enable);
+ __fimc_md_modify_pipeline(pad_err->entity, !enable);
- if (entity_err == entity)
+ if (pad_err == pad)
break;
}
@@ -222,8 +222,8 @@ static int isp_video_get_graph_data(struct isp_video *video,
struct isp_pipeline *pipe)
{
struct media_graph graph;
- struct media_entity *entity = &video->video.entity;
- struct media_device *mdev = entity->graph_obj.mdev;
+ struct media_pad *pad = video->video.entity.pads;
+ struct media_device *mdev = video->video.entity.graph_obj.mdev;
struct isp_video *far_end = NULL;
int ret;
@@ -234,23 +234,24 @@ static int isp_video_get_graph_data(struct isp_video *video,
return ret;
}
- media_graph_walk_start(&graph, entity->pads);
+ media_graph_walk_start(&graph, pad);
- while ((entity = media_graph_walk_next(&graph))) {
+ while ((pad = media_graph_walk_next(&graph))) {
struct isp_video *__video;
- media_entity_enum_set(&pipe->ent_enum, entity);
+ media_entity_enum_set(&pipe->ent_enum, pad->entity);
if (far_end != NULL)
continue;
- if (entity == &video->video.entity)
+ if (pad == video->video.entity.pads)
continue;
- if (!is_media_entity_v4l2_video_device(entity))
+ if (!is_media_entity_v4l2_video_device(pad->entity))
continue;
- __video = to_isp_video(media_entity_to_video_device(entity));
+ __video = to_isp_video(media_entity_to_video_device(
+ pad->entity));
if (__video->type != video->type)
far_end = __video;
}
@@ -559,8 +559,8 @@ static int vsp1_video_pipeline_build(struct vsp1_pipeline *pipe,
struct vsp1_video *video)
{
struct media_graph graph;
- struct media_entity *entity = &video->video.entity;
- struct media_device *mdev = entity->graph_obj.mdev;
+ struct media_pad *pad = video->video.entity.pads;
+ struct media_device *mdev = video->video.entity.graph_obj.mdev;
unsigned int i;
int ret;
@@ -569,17 +569,17 @@ static int vsp1_video_pipeline_build(struct vsp1_pipeline *pipe,
if (ret)
return ret;
- media_graph_walk_start(&graph, entity->pads);
+ media_graph_walk_start(&graph, pad);
- while ((entity = media_graph_walk_next(&graph))) {
+ while ((pad = media_graph_walk_next(&graph))) {
struct v4l2_subdev *subdev;
struct vsp1_rwpf *rwpf;
struct vsp1_entity *e;
- if (!is_media_entity_v4l2_subdev(entity))
+ if (!is_media_entity_v4l2_subdev(pad->entity))
continue;
- subdev = media_entity_to_v4l2_subdev(entity);
+ subdev = media_entity_to_v4l2_subdev(pad->entity);
e = to_vsp1_entity(subdev);
list_add_tail(&e->list_pipe, &pipe->entities);
e->pipe = pipe;
@@ -175,8 +175,8 @@ static int xvip_pipeline_validate(struct xvip_pipeline *pipe,
struct xvip_dma *start)
{
struct media_graph graph;
- struct media_entity *entity = &start->video.entity;
- struct media_device *mdev = entity->graph_obj.mdev;
+ struct media_pad *pad = start->video.entity.pads;
+ struct media_device *mdev = pad->entity->graph_obj.mdev;
unsigned int num_inputs = 0;
unsigned int num_outputs = 0;
int ret;
@@ -190,15 +190,15 @@ static int xvip_pipeline_validate(struct xvip_pipeline *pipe,
return ret;
}
- media_graph_walk_start(&graph, entity->pads);
+ media_graph_walk_start(&graph, pad);
- while ((entity = media_graph_walk_next(&graph))) {
+ while ((pad = media_graph_walk_next(&graph))) {
struct xvip_dma *dma;
- if (entity->function != MEDIA_ENT_F_IO_V4L)
+ if (pad->entity->function != MEDIA_ENT_F_IO_V4L)
continue;
- dma = to_xvip_dma(media_entity_to_video_device(entity));
+ dma = to_xvip_dma(media_entity_to_video_device(pad->entity));
if (dma->pad.flags & MEDIA_PAD_FL_SINK) {
pipe->output = dma;
@@ -434,13 +434,14 @@ EXPORT_SYMBOL_GPL(v4l2_create_fwnode_links);
static int pipeline_pm_use_count(struct media_entity *entity,
struct media_graph *graph)
{
+ struct media_pad *pad;
int use = 0;
media_graph_walk_start(graph, entity->pads);
- while ((entity = media_graph_walk_next(graph))) {
- if (is_media_entity_v4l2_video_device(entity))
- use += entity->use_count;
+ while ((pad = media_graph_walk_next(graph))) {
+ if (is_media_entity_v4l2_video_device(pad->entity))
+ use += pad->entity->use_count;
}
return use;
@@ -493,7 +494,7 @@ static int pipeline_pm_power_one(struct media_entity *entity, int change)
static int pipeline_pm_power(struct media_entity *entity, int change,
struct media_graph *graph)
{
- struct media_entity *first = entity;
+ struct media_pad *tmp_pad, *pad;
int ret = 0;
if (!change)
@@ -501,19 +502,18 @@ static int pipeline_pm_power(struct media_entity *entity, int change,
media_graph_walk_start(graph, entity->pads);
- while (!ret && (entity = media_graph_walk_next(graph)))
- if (is_media_entity_v4l2_subdev(entity))
- ret = pipeline_pm_power_one(entity, change);
+ while (!ret && (pad = media_graph_walk_next(graph)))
+ if (is_media_entity_v4l2_subdev(pad->entity))
+ ret = pipeline_pm_power_one(pad->entity, change);
if (!ret)
return ret;
- media_graph_walk_start(graph, first->pads);
+ media_graph_walk_start(graph, entity->pads);
- while ((first = media_graph_walk_next(graph))
- && first != entity)
- if (is_media_entity_v4l2_subdev(first))
- pipeline_pm_power_one(first, -change);
+ while ((tmp_pad = media_graph_walk_next(graph)) && tmp_pad != pad)
+ if (is_media_entity_v4l2_subdev(tmp_pad->entity))
+ pipeline_pm_power_one(tmp_pad->entity, -change);
return ret;
}
@@ -206,8 +206,8 @@ static struct iss_video *
iss_video_far_end(struct iss_video *video)
{
struct media_graph graph;
- struct media_entity *entity = &video->video.entity;
- struct media_device *mdev = entity->graph_obj.mdev;
+ struct media_pad *pad = video->video.entity.pads;
+ struct media_device *mdev = video->video.entity.graph_obj.mdev;
struct iss_video *far_end = NULL;
mutex_lock(&mdev->graph_mutex);
@@ -217,16 +217,17 @@ iss_video_far_end(struct iss_video *video)
return NULL;
}
- media_graph_walk_start(&graph, entity->pads);
+ media_graph_walk_start(&graph, pad);
- while ((entity = media_graph_walk_next(&graph))) {
- if (entity == &video->video.entity)
+ while ((pad = media_graph_walk_next(&graph))) {
+ if (pad->entity == &video->video.entity)
continue;
- if (!is_media_entity_v4l2_video_device(entity))
+ if (!is_media_entity_v4l2_video_device(pad->entity))
continue;
- far_end = to_iss_video(media_entity_to_video_device(entity));
+ far_end = to_iss_video(media_entity_to_video_device(
+ pad->entity));
if (far_end->type != video->type)
break;
@@ -853,7 +854,7 @@ iss_video_streamon(struct file *file, void *fh, enum v4l2_buf_type type)
struct iss_video_fh *vfh = to_iss_video_fh(fh);
struct iss_video *video = video_drvdata(file);
struct media_graph graph;
- struct media_entity *entity = &video->video.entity;
+ struct media_pad *pad = video->video.entity.pads;
enum iss_pipeline_state state;
struct iss_pipeline *pipe;
struct iss_video *far_end;
@@ -869,30 +870,31 @@ iss_video_streamon(struct file *file, void *fh, enum v4l2_buf_type type)
* Start streaming on the pipeline. No link touching an entity in the
* pipeline can be activated or deactivated once streaming is started.
*/
- pipe = entity->pipe
- ? to_iss_pipeline(entity) : &video->pipe;
+ pipe = pad->entity->pipe
+ ? to_iss_pipeline(pad->entity) : &video->pipe;
pipe->external = NULL;
pipe->external_rate = 0;
pipe->external_bpp = 0;
- ret = media_entity_enum_init(&pipe->ent_enum, entity->graph_obj.mdev);
+ ret = media_entity_enum_init(&pipe->ent_enum,
+ pad->entity->graph_obj.mdev);
if (ret)
goto err_graph_walk_init;
- ret = media_graph_walk_init(&graph, entity->graph_obj.mdev);
+ ret = media_graph_walk_init(&graph, pad->entity->graph_obj.mdev);
if (ret)
goto err_graph_walk_init;
if (video->iss->pdata->set_constraints)
video->iss->pdata->set_constraints(video->iss, true);
- ret = media_pipeline_start(entity, &pipe->pipe);
+ ret = media_pipeline_start(pad->entity, &pipe->pipe);
if (ret < 0)
goto err_media_pipeline_start;
- media_graph_walk_start(&graph, entity->pads);
- while ((entity = media_graph_walk_next(&graph)))
- media_entity_enum_set(&pipe->ent_enum, entity);
+ media_graph_walk_start(&graph, pad);
+ while ((pad = media_graph_walk_next(&graph)))
+ media_entity_enum_set(&pipe->ent_enum, pad->entity);
/*
* Verify that the currently configured format matches the output of
@@ -921,10 +921,11 @@ void media_graph_walk_start(struct media_graph *graph, struct media_pad *pad);
* The graph structure must have been previously initialized with a call to
* media_graph_walk_start().
*
- * Return: returns the next entity in the graph or %NULL if the whole graph
- * have been traversed.
+ * Return: returns the next entity in the graph, identified by the pad through
+ * which it has been reached. If the whole graph has been traversed, return
+ * %NULL.
*/
-struct media_entity *media_graph_walk_next(struct media_graph *graph);
+struct media_pad *media_graph_walk_next(struct media_graph *graph);
/**
* media_pipeline_start - Mark a pipeline as streaming