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mc-entity.c
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// SPDX-License-Identifier: GPL-2.0-only
/*
* Media entity
*
* Copyright (C) 2010 Nokia Corporation
*
* Contacts: Laurent Pinchart <[email protected]>
* Sakari Ailus <[email protected]>
*/
#include <linux/bitmap.h>
#include <linux/list.h>
#include <linux/property.h>
#include <linux/slab.h>
#include <media/media-entity.h>
#include <media/media-device.h>
static inline const char *intf_type(struct media_interface *intf)
{
switch (intf->type) {
case MEDIA_INTF_T_DVB_FE:
return "dvb-frontend";
case MEDIA_INTF_T_DVB_DEMUX:
return "dvb-demux";
case MEDIA_INTF_T_DVB_DVR:
return "dvb-dvr";
case MEDIA_INTF_T_DVB_CA:
return "dvb-ca";
case MEDIA_INTF_T_DVB_NET:
return "dvb-net";
case MEDIA_INTF_T_V4L_VIDEO:
return "v4l-video";
case MEDIA_INTF_T_V4L_VBI:
return "v4l-vbi";
case MEDIA_INTF_T_V4L_RADIO:
return "v4l-radio";
case MEDIA_INTF_T_V4L_SUBDEV:
return "v4l-subdev";
case MEDIA_INTF_T_V4L_SWRADIO:
return "v4l-swradio";
case MEDIA_INTF_T_V4L_TOUCH:
return "v4l-touch";
default:
return "unknown-intf";
}
};
static inline const char *link_type_name(struct media_link *link)
{
switch (link->flags & MEDIA_LNK_FL_LINK_TYPE) {
case MEDIA_LNK_FL_DATA_LINK:
return "data";
case MEDIA_LNK_FL_INTERFACE_LINK:
return "interface";
case MEDIA_LNK_FL_ANCILLARY_LINK:
return "ancillary";
default:
return "unknown";
}
}
__must_check int media_entity_enum_init(struct media_entity_enum *ent_enum,
struct media_device *mdev)
{
int idx_max;
idx_max = ALIGN(mdev->entity_internal_idx_max + 1, BITS_PER_LONG);
ent_enum->bmap = bitmap_zalloc(idx_max, GFP_KERNEL);
if (!ent_enum->bmap)
return -ENOMEM;
ent_enum->idx_max = idx_max;
return 0;
}
EXPORT_SYMBOL_GPL(media_entity_enum_init);
void media_entity_enum_cleanup(struct media_entity_enum *ent_enum)
{
bitmap_free(ent_enum->bmap);
}
EXPORT_SYMBOL_GPL(media_entity_enum_cleanup);
/**
* dev_dbg_obj - Prints in debug mode a change on some object
*
* @event_name: Name of the event to report. Could be __func__
* @gobj: Pointer to the object
*
* Enabled only if DEBUG or CONFIG_DYNAMIC_DEBUG. Otherwise, it
* won't produce any code.
*/
static void dev_dbg_obj(const char *event_name, struct media_gobj *gobj)
{
#if defined(DEBUG) || defined (CONFIG_DYNAMIC_DEBUG)
switch (media_type(gobj)) {
case MEDIA_GRAPH_ENTITY:
dev_dbg(gobj->mdev->dev,
"%s id %u: entity '%s'\n",
event_name, media_id(gobj),
gobj_to_entity(gobj)->name);
break;
case MEDIA_GRAPH_LINK:
{
struct media_link *link = gobj_to_link(gobj);
dev_dbg(gobj->mdev->dev,
"%s id %u: %s link id %u ==> id %u\n",
event_name, media_id(gobj), link_type_name(link),
media_id(link->gobj0),
media_id(link->gobj1));
break;
}
case MEDIA_GRAPH_PAD:
{
struct media_pad *pad = gobj_to_pad(gobj);
dev_dbg(gobj->mdev->dev,
"%s id %u: %s%spad '%s':%d\n",
event_name, media_id(gobj),
pad->flags & MEDIA_PAD_FL_SINK ? "sink " : "",
pad->flags & MEDIA_PAD_FL_SOURCE ? "source " : "",
pad->entity->name, pad->index);
break;
}
case MEDIA_GRAPH_INTF_DEVNODE:
{
struct media_interface *intf = gobj_to_intf(gobj);
struct media_intf_devnode *devnode = intf_to_devnode(intf);
dev_dbg(gobj->mdev->dev,
"%s id %u: intf_devnode %s - major: %d, minor: %d\n",
event_name, media_id(gobj),
intf_type(intf),
devnode->major, devnode->minor);
break;
}
}
#endif
}
void media_gobj_create(struct media_device *mdev,
enum media_gobj_type type,
struct media_gobj *gobj)
{
BUG_ON(!mdev);
gobj->mdev = mdev;
/* Create a per-type unique object ID */
gobj->id = media_gobj_gen_id(type, ++mdev->id);
switch (type) {
case MEDIA_GRAPH_ENTITY:
list_add_tail(&gobj->list, &mdev->entities);
break;
case MEDIA_GRAPH_PAD:
list_add_tail(&gobj->list, &mdev->pads);
break;
case MEDIA_GRAPH_LINK:
list_add_tail(&gobj->list, &mdev->links);
break;
case MEDIA_GRAPH_INTF_DEVNODE:
list_add_tail(&gobj->list, &mdev->interfaces);
break;
}
mdev->topology_version++;
dev_dbg_obj(__func__, gobj);
}
void media_gobj_destroy(struct media_gobj *gobj)
{
/* Do nothing if the object is not linked. */
if (gobj->mdev == NULL)
return;
dev_dbg_obj(__func__, gobj);
gobj->mdev->topology_version++;
/* Remove the object from mdev list */
list_del(&gobj->list);
gobj->mdev = NULL;
}
/*
* TODO: Get rid of this.
*/
#define MEDIA_ENTITY_MAX_PADS 512
int media_entity_pads_init(struct media_entity *entity, u16 num_pads,
struct media_pad *pads)
{
struct media_device *mdev = entity->graph_obj.mdev;
struct media_pad *iter;
unsigned int i = 0;
if (num_pads >= MEDIA_ENTITY_MAX_PADS)
return -E2BIG;
entity->num_pads = num_pads;
entity->pads = pads;
if (mdev)
mutex_lock(&mdev->graph_mutex);
media_entity_for_each_pad(entity, iter) {
iter->entity = entity;
iter->index = i++;
if (mdev)
media_gobj_create(mdev, MEDIA_GRAPH_PAD,
&iter->graph_obj);
}
if (mdev)
mutex_unlock(&mdev->graph_mutex);
return 0;
}
EXPORT_SYMBOL_GPL(media_entity_pads_init);
/* -----------------------------------------------------------------------------
* Graph traversal
*/
/**
* media_entity_has_pad_interdep - Check interdependency between two pads
*
* @entity: The entity
* @pad0: The first pad index
* @pad1: The second pad index
*
* This function checks the interdependency inside the entity between @pad0
* and @pad1. If two pads are interdependent they are part of the same pipeline
* and enabling one of the pads means that the other pad will become "locked"
* and doesn't allow configuration changes.
*
* This function uses the &media_entity_operations.has_pad_interdep() operation
* to check the dependency inside the entity between @pad0 and @pad1. If the
* has_pad_interdep operation is not implemented, all pads of the entity are
* considered to be interdependent.
*
* One of @pad0 and @pad1 must be a sink pad and the other one a source pad.
* The function returns false if both pads are sinks or sources.
*
* The caller must hold entity->graph_obj.mdev->mutex.
*
* Return: true if the pads are connected internally and false otherwise.
*/
static bool media_entity_has_pad_interdep(struct media_entity *entity,
unsigned int pad0, unsigned int pad1)
{
if (pad0 >= entity->num_pads || pad1 >= entity->num_pads)
return false;
if (entity->pads[pad0].flags & entity->pads[pad1].flags &
(MEDIA_PAD_FL_SINK | MEDIA_PAD_FL_SOURCE))
return false;
if (!entity->ops || !entity->ops->has_pad_interdep)
return true;
return entity->ops->has_pad_interdep(entity, pad0, pad1);
}
static struct media_entity *
media_entity_other(struct media_entity *entity, struct media_link *link)
{
if (link->source->entity == entity)
return link->sink->entity;
else
return link->source->entity;
}
/* push an entity to traversal stack */
static void stack_push(struct media_graph *graph,
struct media_entity *entity)
{
if (graph->top == MEDIA_ENTITY_ENUM_MAX_DEPTH - 1) {
WARN_ON(1);
return;
}
graph->top++;
graph->stack[graph->top].link = entity->links.next;
graph->stack[graph->top].entity = entity;
}
static struct media_entity *stack_pop(struct media_graph *graph)
{
struct media_entity *entity;
entity = graph->stack[graph->top].entity;
graph->top--;
return entity;
}
#define link_top(en) ((en)->stack[(en)->top].link)
#define stack_top(en) ((en)->stack[(en)->top].entity)
/**
* media_graph_walk_init - Allocate resources for graph walk
* @graph: Media graph structure that will be used to walk the graph
* @mdev: Media device
*
* Reserve resources for graph walk in media device's current
* state. The memory must be released using
* media_graph_walk_cleanup().
*
* Returns error on failure, zero on success.
*/
__must_check int media_graph_walk_init(
struct media_graph *graph, struct media_device *mdev)
{
return media_entity_enum_init(&graph->ent_enum, mdev);
}
EXPORT_SYMBOL_GPL(media_graph_walk_init);
/**
* media_graph_walk_cleanup - Release resources related to graph walking
* @graph: Media graph structure that was used to walk the graph
*/
void media_graph_walk_cleanup(struct media_graph *graph)
{
media_entity_enum_cleanup(&graph->ent_enum);
}
EXPORT_SYMBOL_GPL(media_graph_walk_cleanup);
void media_graph_walk_start(struct media_graph *graph,
struct media_entity *entity)
{
media_entity_enum_zero(&graph->ent_enum);
media_entity_enum_set(&graph->ent_enum, entity);
graph->top = 0;
graph->stack[graph->top].entity = NULL;
stack_push(graph, entity);
dev_dbg(entity->graph_obj.mdev->dev,
"begin graph walk at '%s'\n", entity->name);
}
EXPORT_SYMBOL_GPL(media_graph_walk_start);
static void media_graph_walk_iter(struct media_graph *graph)
{
struct media_entity *entity = stack_top(graph);
struct media_link *link;
struct media_entity *next;
link = list_entry(link_top(graph), typeof(*link), list);
/* If the link is not a data link, don't follow it */
if ((link->flags & MEDIA_LNK_FL_LINK_TYPE) != MEDIA_LNK_FL_DATA_LINK) {
link_top(graph) = link_top(graph)->next;
return;
}
/* The link is not enabled so we do not follow. */
if (!(link->flags & MEDIA_LNK_FL_ENABLED)) {
link_top(graph) = link_top(graph)->next;
dev_dbg(entity->graph_obj.mdev->dev,
"walk: skipping disabled link '%s':%u -> '%s':%u\n",
link->source->entity->name, link->source->index,
link->sink->entity->name, link->sink->index);
return;
}
/* Get the entity at the other end of the link. */
next = media_entity_other(entity, link);
/* Has the entity already been visited? */
if (media_entity_enum_test_and_set(&graph->ent_enum, next)) {
link_top(graph) = link_top(graph)->next;
dev_dbg(entity->graph_obj.mdev->dev,
"walk: skipping entity '%s' (already seen)\n",
next->name);
return;
}
/* Push the new entity to stack and start over. */
link_top(graph) = link_top(graph)->next;
stack_push(graph, next);
dev_dbg(entity->graph_obj.mdev->dev, "walk: pushing '%s' on stack\n",
next->name);
lockdep_assert_held(&entity->graph_obj.mdev->graph_mutex);
}
struct media_entity *media_graph_walk_next(struct media_graph *graph)
{
struct media_entity *entity;
if (stack_top(graph) == NULL)
return NULL;
/*
* Depth first search. Push entity to stack and continue from
* top of the stack until no more entities on the level can be
* found.
*/
while (link_top(graph) != &stack_top(graph)->links)
media_graph_walk_iter(graph);
entity = stack_pop(graph);
dev_dbg(entity->graph_obj.mdev->dev,
"walk: returning entity '%s'\n", entity->name);
return entity;
}
EXPORT_SYMBOL_GPL(media_graph_walk_next);
/* -----------------------------------------------------------------------------
* Pipeline management
*/
/*
* The pipeline traversal stack stores pads that are reached during graph
* traversal, with a list of links to be visited to continue the traversal.
* When a new pad is reached, an entry is pushed on the top of the stack and
* points to the incoming pad and the first link of the entity.
*
* To find further pads in the pipeline, the traversal algorithm follows
* internal pad dependencies in the entity, and then links in the graph. It
* does so by iterating over all links of the entity, and following enabled
* links that originate from a pad that is internally connected to the incoming
* pad, as reported by the media_entity_has_pad_interdep() function.
*/
/**
* struct media_pipeline_walk_entry - Entry in the pipeline traversal stack
*
* @pad: The media pad being visited
* @links: Links left to be visited
*/
struct media_pipeline_walk_entry {
struct media_pad *pad;
struct list_head *links;
};
/**
* struct media_pipeline_walk - State used by the media pipeline traversal
* algorithm
*
* @mdev: The media device
* @stack: Depth-first search stack
* @stack.size: Number of allocated entries in @stack.entries
* @stack.top: Index of the top stack entry (-1 if the stack is empty)
* @stack.entries: Stack entries
*/
struct media_pipeline_walk {
struct media_device *mdev;
struct {
unsigned int size;
int top;
struct media_pipeline_walk_entry *entries;
} stack;
};
#define MEDIA_PIPELINE_STACK_GROW_STEP 16
static struct media_pipeline_walk_entry *
media_pipeline_walk_top(struct media_pipeline_walk *walk)
{
return &walk->stack.entries[walk->stack.top];
}
static bool media_pipeline_walk_empty(struct media_pipeline_walk *walk)
{
return walk->stack.top == -1;
}
/* Increase the stack size by MEDIA_PIPELINE_STACK_GROW_STEP elements. */
static int media_pipeline_walk_resize(struct media_pipeline_walk *walk)
{
struct media_pipeline_walk_entry *entries;
unsigned int new_size;
/* Safety check, to avoid stack overflows in case of bugs. */
if (walk->stack.size >= 256)
return -E2BIG;
new_size = walk->stack.size + MEDIA_PIPELINE_STACK_GROW_STEP;
entries = krealloc(walk->stack.entries,
new_size * sizeof(*walk->stack.entries),
GFP_KERNEL);
if (!entries)
return -ENOMEM;
walk->stack.entries = entries;
walk->stack.size = new_size;
return 0;
}
/* Push a new entry on the stack. */
static int media_pipeline_walk_push(struct media_pipeline_walk *walk,
struct media_pad *pad)
{
struct media_pipeline_walk_entry *entry;
int ret;
if (walk->stack.top + 1 >= walk->stack.size) {
ret = media_pipeline_walk_resize(walk);
if (ret)
return ret;
}
walk->stack.top++;
entry = media_pipeline_walk_top(walk);
entry->pad = pad;
entry->links = pad->entity->links.next;
dev_dbg(walk->mdev->dev,
"media pipeline: pushed entry %u: '%s':%u\n",
walk->stack.top, pad->entity->name, pad->index);
return 0;
}
/*
* Move the top entry link cursor to the next link. If all links of the entry
* have been visited, pop the entry itself.
*/
static void media_pipeline_walk_pop(struct media_pipeline_walk *walk)
{
struct media_pipeline_walk_entry *entry;
if (WARN_ON(walk->stack.top < 0))
return;
entry = media_pipeline_walk_top(walk);
if (entry->links->next == &entry->pad->entity->links) {
dev_dbg(walk->mdev->dev,
"media pipeline: entry %u has no more links, popping\n",
walk->stack.top);
walk->stack.top--;
return;
}
entry->links = entry->links->next;
dev_dbg(walk->mdev->dev,
"media pipeline: moved entry %u to next link\n",
walk->stack.top);
}
/* Free all memory allocated while walking the pipeline. */
static void media_pipeline_walk_destroy(struct media_pipeline_walk *walk)
{
kfree(walk->stack.entries);
}
/* Add a pad to the pipeline and push it to the stack. */
static int media_pipeline_add_pad(struct media_pipeline *pipe,
struct media_pipeline_walk *walk,
struct media_pad *pad)
{
struct media_pipeline_pad *ppad;
list_for_each_entry(ppad, &pipe->pads, list) {
if (ppad->pad == pad) {
dev_dbg(pad->graph_obj.mdev->dev,
"media pipeline: already contains pad '%s':%u\n",
pad->entity->name, pad->index);
return 0;
}
}
ppad = kzalloc(sizeof(*ppad), GFP_KERNEL);
if (!ppad)
return -ENOMEM;
ppad->pipe = pipe;
ppad->pad = pad;
list_add_tail(&ppad->list, &pipe->pads);
dev_dbg(pad->graph_obj.mdev->dev,
"media pipeline: added pad '%s':%u\n",
pad->entity->name, pad->index);
return media_pipeline_walk_push(walk, pad);
}
/* Explore the next link of the entity at the top of the stack. */
static int media_pipeline_explore_next_link(struct media_pipeline *pipe,
struct media_pipeline_walk *walk)
{
struct media_pipeline_walk_entry *entry = media_pipeline_walk_top(walk);
struct media_pad *pad;
struct media_link *link;
struct media_pad *local;
struct media_pad *remote;
int ret;
pad = entry->pad;
link = list_entry(entry->links, typeof(*link), list);
media_pipeline_walk_pop(walk);
dev_dbg(walk->mdev->dev,
"media pipeline: exploring link '%s':%u -> '%s':%u\n",
link->source->entity->name, link->source->index,
link->sink->entity->name, link->sink->index);
/* Skip links that are not enabled. */
if (!(link->flags & MEDIA_LNK_FL_ENABLED)) {
dev_dbg(walk->mdev->dev,
"media pipeline: skipping link (disabled)\n");
return 0;
}
/* Get the local pad and remote pad. */
if (link->source->entity == pad->entity) {
local = link->source;
remote = link->sink;
} else {
local = link->sink;
remote = link->source;
}
/*
* Skip links that originate from a different pad than the incoming pad
* that is not connected internally in the entity to the incoming pad.
*/
if (pad != local &&
!media_entity_has_pad_interdep(pad->entity, pad->index, local->index)) {
dev_dbg(walk->mdev->dev,
"media pipeline: skipping link (no route)\n");
return 0;
}
/*
* Add the local and remote pads of the link to the pipeline and push
* them to the stack, if they're not already present.
*/
ret = media_pipeline_add_pad(pipe, walk, local);
if (ret)
return ret;
ret = media_pipeline_add_pad(pipe, walk, remote);
if (ret)
return ret;
return 0;
}
static void media_pipeline_cleanup(struct media_pipeline *pipe)
{
while (!list_empty(&pipe->pads)) {
struct media_pipeline_pad *ppad;
ppad = list_first_entry(&pipe->pads, typeof(*ppad), list);
list_del(&ppad->list);
kfree(ppad);
}
}
static int media_pipeline_populate(struct media_pipeline *pipe,
struct media_pad *pad)
{
struct media_pipeline_walk walk = { };
struct media_pipeline_pad *ppad;
int ret;
/*
* Populate the media pipeline by walking the media graph, starting
* from @pad.
*/
INIT_LIST_HEAD(&pipe->pads);
pipe->mdev = pad->graph_obj.mdev;
walk.mdev = pipe->mdev;
walk.stack.top = -1;
ret = media_pipeline_add_pad(pipe, &walk, pad);
if (ret)
goto done;
/*
* Use a depth-first search algorithm: as long as the stack is not
* empty, explore the next link of the top entry. The
* media_pipeline_explore_next_link() function will either move to the
* next link, pop the entry if fully visited, or add new entries on
* top.
*/
while (!media_pipeline_walk_empty(&walk)) {
ret = media_pipeline_explore_next_link(pipe, &walk);
if (ret)
goto done;
}
dev_dbg(pad->graph_obj.mdev->dev,
"media pipeline populated, found pads:\n");
list_for_each_entry(ppad, &pipe->pads, list)
dev_dbg(pad->graph_obj.mdev->dev, "- '%s':%u\n",
ppad->pad->entity->name, ppad->pad->index);
WARN_ON(walk.stack.top != -1);
ret = 0;
done:
media_pipeline_walk_destroy(&walk);
if (ret)
media_pipeline_cleanup(pipe);
return ret;
}
__must_check int __media_pipeline_start(struct media_pad *pad,
struct media_pipeline *pipe)
{
struct media_device *mdev = pad->graph_obj.mdev;
struct media_pipeline_pad *err_ppad;
struct media_pipeline_pad *ppad;
int ret;
lockdep_assert_held(&mdev->graph_mutex);
/*
* If the pad is already part of a pipeline, that pipeline must be the
* same as the pipe given to media_pipeline_start().
*/
if (WARN_ON(pad->pipe && pad->pipe != pipe))
return -EINVAL;
/*
* If the pipeline has already been started, it is guaranteed to be
* valid, so just increase the start count.
*/
if (pipe->start_count) {
pipe->start_count++;
return 0;
}
/*
* Populate the pipeline. This populates the media_pipeline pads list
* with media_pipeline_pad instances for each pad found during graph
* walk.
*/
ret = media_pipeline_populate(pipe, pad);
if (ret)
return ret;
/*
* Now that all the pads in the pipeline have been gathered, perform
* the validation steps.
*/
list_for_each_entry(ppad, &pipe->pads, list) {
struct media_pad *pad = ppad->pad;
struct media_entity *entity = pad->entity;
bool has_enabled_link = false;
bool has_link = false;
struct media_link *link;
dev_dbg(mdev->dev, "Validating pad '%s':%u\n", pad->entity->name,
pad->index);
/*
* 1. Ensure that the pad doesn't already belong to a different
* pipeline.
*/
if (pad->pipe) {
dev_dbg(mdev->dev, "Failed to start pipeline: pad '%s':%u busy\n",
pad->entity->name, pad->index);
ret = -EBUSY;
goto error;
}
/*
* 2. Validate all active links whose sink is the current pad.
* Validation of the source pads is performed in the context of
* the connected sink pad to avoid duplicating checks.
*/
for_each_media_entity_data_link(entity, link) {
/* Skip links unrelated to the current pad. */
if (link->sink != pad && link->source != pad)
continue;
/* Record if the pad has links and enabled links. */
if (link->flags & MEDIA_LNK_FL_ENABLED)
has_enabled_link = true;
has_link = true;
/*
* Validate the link if it's enabled and has the
* current pad as its sink.
*/
if (!(link->flags & MEDIA_LNK_FL_ENABLED))
continue;
if (link->sink != pad)
continue;
if (!entity->ops || !entity->ops->link_validate)
continue;
ret = entity->ops->link_validate(link);
if (ret) {
dev_dbg(mdev->dev,
"Link '%s':%u -> '%s':%u failed validation: %d\n",
link->source->entity->name,
link->source->index,
link->sink->entity->name,
link->sink->index, ret);
goto error;
}
dev_dbg(mdev->dev,
"Link '%s':%u -> '%s':%u is valid\n",
link->source->entity->name,
link->source->index,
link->sink->entity->name,
link->sink->index);
}
/*
* 3. If the pad has the MEDIA_PAD_FL_MUST_CONNECT flag set,
* ensure that it has either no link or an enabled link.
*/
if ((pad->flags & MEDIA_PAD_FL_MUST_CONNECT) && has_link &&
!has_enabled_link) {
dev_dbg(mdev->dev,
"Pad '%s':%u must be connected by an enabled link\n",
pad->entity->name, pad->index);
ret = -ENOLINK;
goto error;
}
/* Validation passed, store the pipe pointer in the pad. */
pad->pipe = pipe;
}
pipe->start_count++;
return 0;
error:
/*
* Link validation on graph failed. We revert what we did and
* return the error.
*/
list_for_each_entry(err_ppad, &pipe->pads, list) {
if (err_ppad == ppad)
break;
err_ppad->pad->pipe = NULL;
}
media_pipeline_cleanup(pipe);
return ret;
}
EXPORT_SYMBOL_GPL(__media_pipeline_start);
__must_check int media_pipeline_start(struct media_pad *pad,
struct media_pipeline *pipe)
{
struct media_device *mdev = pad->graph_obj.mdev;
int ret;
mutex_lock(&mdev->graph_mutex);
ret = __media_pipeline_start(pad, pipe);
mutex_unlock(&mdev->graph_mutex);
return ret;
}
EXPORT_SYMBOL_GPL(media_pipeline_start);
void __media_pipeline_stop(struct media_pad *pad)
{
struct media_pipeline *pipe = pad->pipe;
struct media_pipeline_pad *ppad;
/*
* If the following check fails, the driver has performed an
* unbalanced call to media_pipeline_stop()
*/
if (WARN_ON(!pipe))
return;
if (--pipe->start_count)
return;
list_for_each_entry(ppad, &pipe->pads, list)
ppad->pad->pipe = NULL;
media_pipeline_cleanup(pipe);
if (pipe->allocated)
kfree(pipe);
}
EXPORT_SYMBOL_GPL(__media_pipeline_stop);
void media_pipeline_stop(struct media_pad *pad)
{
struct media_device *mdev = pad->graph_obj.mdev;
mutex_lock(&mdev->graph_mutex);
__media_pipeline_stop(pad);
mutex_unlock(&mdev->graph_mutex);
}
EXPORT_SYMBOL_GPL(media_pipeline_stop);
__must_check int media_pipeline_alloc_start(struct media_pad *pad)
{
struct media_device *mdev = pad->graph_obj.mdev;
struct media_pipeline *new_pipe = NULL;
struct media_pipeline *pipe;
int ret;
mutex_lock(&mdev->graph_mutex);
/*
* Is the pad already part of a pipeline? If not, we need to allocate
* a pipe.
*/
pipe = media_pad_pipeline(pad);
if (!pipe) {
new_pipe = kzalloc(sizeof(*new_pipe), GFP_KERNEL);
if (!new_pipe) {
ret = -ENOMEM;
goto out;
}
pipe = new_pipe;
pipe->allocated = true;
}
ret = __media_pipeline_start(pad, pipe);
if (ret)
kfree(new_pipe);
out:
mutex_unlock(&mdev->graph_mutex);
return ret;
}
EXPORT_SYMBOL_GPL(media_pipeline_alloc_start);
struct media_pad *
__media_pipeline_pad_iter_next(struct media_pipeline *pipe,
struct media_pipeline_pad_iter *iter,
struct media_pad *pad)
{
if (!pad)
iter->cursor = pipe->pads.next;
if (iter->cursor == &pipe->pads)
return NULL;
pad = list_entry(iter->cursor, struct media_pipeline_pad, list)->pad;
iter->cursor = iter->cursor->next;
return pad;
}
EXPORT_SYMBOL_GPL(__media_pipeline_pad_iter_next);
int media_pipeline_entity_iter_init(struct media_pipeline *pipe,
struct media_pipeline_entity_iter *iter)
{
return media_entity_enum_init(&iter->ent_enum, pipe->mdev);
}
EXPORT_SYMBOL_GPL(media_pipeline_entity_iter_init);
void media_pipeline_entity_iter_cleanup(struct media_pipeline_entity_iter *iter)
{
media_entity_enum_cleanup(&iter->ent_enum);
}
EXPORT_SYMBOL_GPL(media_pipeline_entity_iter_cleanup);
struct media_entity *
__media_pipeline_entity_iter_next(struct media_pipeline *pipe,
struct media_pipeline_entity_iter *iter,
struct media_entity *entity)
{
if (!entity)
iter->cursor = pipe->pads.next;
while (iter->cursor != &pipe->pads) {
struct media_pipeline_pad *ppad;
struct media_entity *entity;
ppad = list_entry(iter->cursor, struct media_pipeline_pad, list);
entity = ppad->pad->entity;
iter->cursor = iter->cursor->next;
if (!media_entity_enum_test_and_set(&iter->ent_enum, entity))
return entity;
}
return NULL;
}