media: v4l2-mc: add v4l2_create_fwnode_links helpers

Add functions to create media links between source and sink subdevices,
based on the fwnode endpoint connections between them:

v4l2_create_fwnode_links_to_pad() - create links from a source subdev to
                                    a single sink pad based on fwnode
                                    endpoint connections.

v4l2_create_fwnode_links() - create all links from a source to sink subdev
                             based on fwnode endpoint connections.

These functions can be used in a sink's v4l2-async notifier subdev
bound callback to make the links from the bound subdev.

Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
This commit is contained in:
Steve Longerbeam 2020-05-01 19:15:37 +02:00 committed by Mauro Carvalho Chehab
parent 8fe784b9ab
commit 0d3c81e82d
2 changed files with 143 additions and 0 deletions

View file

@ -309,6 +309,101 @@ int v4l_vb2q_enable_media_source(struct vb2_queue *q)
}
EXPORT_SYMBOL_GPL(v4l_vb2q_enable_media_source);
int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
struct media_pad *sink)
{
struct fwnode_handle *endpoint;
struct v4l2_subdev *sink_sd;
if (!(sink->flags & MEDIA_PAD_FL_SINK) ||
!is_media_entity_v4l2_subdev(sink->entity))
return -EINVAL;
sink_sd = media_entity_to_v4l2_subdev(sink->entity);
fwnode_graph_for_each_endpoint(dev_fwnode(src_sd->dev), endpoint) {
struct fwnode_handle *remote_ep;
int src_idx, sink_idx, ret;
struct media_pad *src;
src_idx = media_entity_get_fwnode_pad(&src_sd->entity,
endpoint,
MEDIA_PAD_FL_SOURCE);
if (src_idx < 0)
continue;
remote_ep = fwnode_graph_get_remote_endpoint(endpoint);
if (!remote_ep)
continue;
/*
* ask the sink to verify it owns the remote endpoint,
* and translate to a sink pad.
*/
sink_idx = media_entity_get_fwnode_pad(&sink_sd->entity,
remote_ep,
MEDIA_PAD_FL_SINK);
fwnode_handle_put(remote_ep);
if (sink_idx < 0 || sink_idx != sink->index)
continue;
/*
* the source endpoint corresponds to one of its source pads,
* the source endpoint connects to an endpoint at the sink
* entity, and the sink endpoint corresponds to the sink
* pad requested, so we have found an endpoint connection
* that works, create the media link for it.
*/
src = &src_sd->entity.pads[src_idx];
/* skip if link already exists */
if (media_entity_find_link(src, sink))
continue;
dev_dbg(sink_sd->dev, "creating link %s:%d -> %s:%d\n",
src_sd->entity.name, src_idx,
sink_sd->entity.name, sink_idx);
ret = media_create_pad_link(&src_sd->entity, src_idx,
&sink_sd->entity, sink_idx, 0);
if (ret) {
dev_err(sink_sd->dev,
"link %s:%d -> %s:%d failed with %d\n",
src_sd->entity.name, src_idx,
sink_sd->entity.name, sink_idx, ret);
fwnode_handle_put(endpoint);
return ret;
}
}
return 0;
}
EXPORT_SYMBOL_GPL(v4l2_create_fwnode_links_to_pad);
int v4l2_create_fwnode_links(struct v4l2_subdev *src_sd,
struct v4l2_subdev *sink_sd)
{
unsigned int i;
for (i = 0; i < sink_sd->entity.num_pads; i++) {
struct media_pad *pad = &sink_sd->entity.pads[i];
int ret;
if (!(pad->flags & MEDIA_PAD_FL_SINK))
continue;
ret = v4l2_create_fwnode_links_to_pad(src_sd, pad);
if (ret)
return ret;
}
return 0;
}
EXPORT_SYMBOL_GPL(v4l2_create_fwnode_links);
/* -----------------------------------------------------------------------------
* Pipeline power management
*

View file

@ -12,6 +12,7 @@
#include <media/media-device.h>
#include <media/v4l2-dev.h>
#include <media/v4l2-subdev.h>
#include <linux/types.h>
/* We don't need to include pci.h or usb.h here */
@ -84,6 +85,53 @@ void v4l_disable_media_source(struct video_device *vdev);
*/
int v4l_vb2q_enable_media_source(struct vb2_queue *q);
/**
* v4l2_create_fwnode_links_to_pad - Create fwnode-based links from a
* source subdev to a sink subdev pad.
*
* @src_sd - pointer to a source subdev
* @sink - pointer to a subdev sink pad
*
* This function searches for fwnode endpoint connections from a source
* subdevice to a single sink pad, and if suitable connections are found,
* translates them into media links to that pad. The function can be
* called by the sink subdevice, in its v4l2-async notifier subdev bound
* callback, to create links from a bound source subdevice.
*
* .. note::
*
* Any sink subdevice that calls this function must implement the
* .get_fwnode_pad media operation in order to verify endpoints passed
* to the sink are owned by the sink.
*
* Return 0 on success or a negative error code on failure.
*/
int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
struct media_pad *sink);
/**
* v4l2_create_fwnode_links - Create fwnode-based links from a source
* subdev to a sink subdev.
*
* @src_sd - pointer to a source subdevice
* @sink_sd - pointer to a sink subdevice
*
* This function searches for any and all fwnode endpoint connections
* between source and sink subdevices, and translates them into media
* links. The function can be called by the sink subdevice, in its
* v4l2-async notifier subdev bound callback, to create all links from
* a bound source subdevice.
*
* .. note::
*
* Any sink subdevice that calls this function must implement the
* .get_fwnode_pad media operation in order to verify endpoints passed
* to the sink are owned by the sink.
*
* Return 0 on success or a negative error code on failure.
*/
int v4l2_create_fwnode_links(struct v4l2_subdev *src_sd,
struct v4l2_subdev *sink_sd);
/**
* v4l2_pipeline_pm_get - Increase the use count of a pipeline