KernelDoc doesn't appear to handle anonymous structs defined inside
another gracefully. As the struct is internal to the framework graph walk
algorithm, detailed documentation isn't seen very important.
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
It will be needed in struct media_pipeline shortly.
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
This is useful in e.g. knowing whether certain operations have already
been performed for an entity. The users include the framework itself (for
graph walking) and a number of drivers.
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
The internal index can be used internally by the framework in order to keep
track of entities for a purpose or another. The internal index is constant
while it's registered to a media device, but the same index may be re-used
once the entity having that index is unregistered.
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
The media device node is registered and so made visible to user-space
before entities are registered and links created which means that the
media graph obtained by user-space could be only partially enumerated
if that happens too early before all the graph has been created.
To avoid this race condition, split the media init and registration
in separate functions and only register the media device node when
all the pending subdevices have been registered, either explicitly
by the driver or asynchronously using v4l2_async_register_subdev().
The media_device_register() had a check for drivers not filling dev
and model fields but all drivers in mainline set them and not doing
it will be a driver bug so change the function return to void and
add a BUG_ON() for dev being NULL instead.
Also, add a media_device_cleanup() function that will destroy the
graph_mutex that is initialized in media_device_init().
[mchehab@osg.samsung.com: Fix compilation if !CONFIG_MEDIA_CONTROLLER
and remove two warnings added by this changeset]
Suggested-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
There is one struct and two functions that were not documented.
Add the corresponding kernel-doc documentation for them.
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
As we're using the headers file only for documentation, move the
two kernel-doc macros to the header, and fix it to avoid
warnings.
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Improve the documentation to let it clear that the entity function
must be initialized.
Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Several additional functions are described at media-entity.c.
Moving them to the header file, to make the code cleaner and
to have all such macros at the same place.
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Those media_obj_* functions are actually creating/destroying
media graph objects. So, rename them to better represent
what they're actually doing.
No functional changes.
This was created via this small shell script:
for i in $(git grep -l media_gobj_init); do sed s,media_gobj_init,media_gobj_create,g <$i >a && mv a $i; done
for i in $(git grep -l media_gobj_remove); do sed s,media_gobj_remove,media_gobj_destroy,g <$i >a && mv a $i; done
Suggested-by: Sakari Ailus <sakari.ailus@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Now that we moved the content of the media-framework.txt into
the kerneldoc documentation, move the per-function specific
documentation to the corresponding functions and clean it up.
It would be good if we had already the markdown kernel-doc
patches merged upstream, but, while we doesn't have it,
let's make it less ugly at device-drivers.xml.
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
This function was used in the past to free the links
that were allocated by the media controller core.
However, this is not needed anymore. We should likely
get rid of the funcion on some function, but, for now,
let's just convert into an inlined function and let the
compiler to get rid of it.
Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Instead of using a text file, let's put it together with the
struct documentation for the Media Controller.
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Both revision and group_id fields were never used and were always
initialized to zero. Remove them.
Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
With the MC next gen rework, what's left for media_entity_init()
is to just initialize the PADs. However, certain devices, like
a FLASH led/light doesn't have any input or output PAD.
So, there's no reason why calling media_entity_init() would be
mandatory. Also, despite its name, what this function actually
does is to initialize the PADs data. So, rename it to
media_entity_pads_init() in order to reflect that.
The media entity actual init happens during entity register,
at media_device_register_entity(). We should move init of
num_links and num_backlinks to it.
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
We should not be creating device nodes at IRQ contexts. So,
the only flags we'll be using will be GFP_KERNEL. Let's
remove the gfp_flags, in order to make the interface simpler.
If we ever need it, it would be easy to revert those changes.
While here, remove an extra blank line.
Suggested-by: Sakari Ailus <sakari.ailus@iki.fi>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Entities should have one or more functions. Calling it as a
type proofed to not be correct, as an entity could eventually
have more than one type.
So, rename the field as function.
Please notice that this patch doesn't extend support for
multiple function entities. Such change will happen when
we have real case drivers using it.
No functional changes.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Drivers should check if interfaces and interface links were
created. Add a must_check for them.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Due to the graph traversal algorithm currently in usage, we
need a copy of all data links. Those backlinks should not be
send to userspace, as otherwise, all links there will be
duplicated.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Only a few structs are documented on kernel-doc-nano format
(the ones added by the MC next gen patches).
Add a documentation for all structs, and ensure that they'll
be producing the documentation at the Kernel's device driver
DocBook.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
V4L2 device (and subdevice) nodes should create an interface, if the
Media Controller support is enabled.
Please notice that radio devices should not create an entity, as radio
input/output is either via wires or via ALSA.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Tuners actually have at least one connector on its input.
Add a PAD to connect it.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Some parts of the media controller are using mutexes while
others are using spin locks in order to protect creation
and removal of elements in the graph. That's wrong!
Also, the V4L2 core can remove graph elements on non-interactive
context:
BUG: sleeping function called from invalid context at include/linux/sched.h:2776
Fix it by always using spin locks for graph element addition/removal,
just like entity creation/removal is protected at media-device.c
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Just like what's done with entities, when the media controller is
unregistered, release any interface and interface links that
might still be there.
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Add functions to explicitly unregister all entity links.
This function is called automatically when an entity
link is destroyed.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Every time a graph object is added or removed, the version
of the topology changes. That's a requirement for the new
MEDIA_IOC_G_TOPOLOGY, in order to allow userspace to know
that the topology has changed after a previous call to it.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
The MC next gen API sends objects to userspace grouped by
their types.
In the case of pads and links, in order to improve performance
and have a simpler code, the best is to store them also on
separate linked lists at MC.
If we don't do that, we would need this kind of interaction
to send data to userspace (code is in structured english):
for each entity:
for each pad:
store pads
for each entity:
for each link:
store link
for each interface:
for each link:
store link
With would require one nested loop for pads and two nested
loops for links. By using separate linked lists for them,
just one loop would be enough.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Let's control the topology changes inside the graph_object. So, move the
addition and removal of interfaces/entities from the mdev lists to
media_gobj_init() and media_gobj_remove().
The main reason is that mdev should have lists for all object types, as
the new MC api will require to store objects in separate places.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Just like we do with entities, use a similar macro for the
interfaces loop.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Add a new ioctl that will report the entire topology on
one go.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
As we'll be removing entity subtypes from the Kernel, we need
to provide a way for drivers and core to check if a given
entity is represented by a V4L2 subdev or if it is an V4L2
I/O entity (typically with DMA).
Drivers that create entities that don't belong to any defined subdev
category should use MEDIA_ENT_T_V4L2_SUBDEV_UNKNOWN.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
The media device should list the interface objects, so add a linked list
for those interfaces in struct media_device.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Now that we have a new graph object called "interfaces", we
need to be able to link them to the entities.
Add a linked list to the interfaces to allow them to be
linked to the entities.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
By adding an union at media_link, we get for free a way to
represent interface->entity links.
No need to change anything at the code, just at the internal
header file.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
The entire logic that represent graph links were developed on a
time where there were no needs to dynamic remove links. So,
although links are created/removed one by one via some
functions, they're stored as an array inside the entity struct.
As the array may grow, there's a logic inside the code that
checks if the amount of space is not enough to store
the needed links. If it isn't the core uses krealloc()
to change the size of the link, with is bad, as it
leaves the memory fragmented.
So, convert links into a list.
Also, currently, both source and sink entities need the link
at the graph traversal logic inside media_entity. So there's
a logic duplicating all links. That makes it to spend
twice the memory needed. This is not a big deal for today's
usage, where the number of links are not big.
Yet, if during the MC workshop discussions, it was said that
IIO graphs could have up to 4,000 entities. So, we may
want to remove the duplication on some future. The problem
is that it would require a separate linked list to store
the backlinks inside the entity, or to use a more complex
algorithm to do graph backlink traversal, with is something
that the current graph traversal inside the core can't cope
with. So, let's postpone a such change if/when it is actually
needed.
It should also be noticed that the media_link structure uses
44 bytes on 32-bit architectures and 84 bytes on 64-bit
architecture. It will thus be allocated out of the 64-bytes and
96-bytes pools respectively. That's a 12.5% memory waste on
64-bit architectures and 31.25% on 32-bit architecture.
A linked list is less efficient than an array in this case, but
this could later be optimized if we can get rid of the reverse
links (with would reduce memory allocation by 50%).
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Interfaces are different than entities: they represent a
Kernel<->userspace interaction, while entities represent a
piece of hardware/firmware/software that executes a function.
Let's distinguish them by creating a separate structure to
store the interfaces.
Later patches should change the existing drivers and logic
to split the current interface embedded inside the entity
structure (device nodes) into a separate object of the graph.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Now that the struct media_entity .parent field is unused, it can be
safely removed. Since all the previous users were converted to use
the .mdev field from the embedded struct media_gobj instead.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
With the new API, a link can be either between two PADs or between an interface
and an entity. So, we need to use a better name for the function that create
links between two pads.
So, rename the such function to media_create_pad_link().
No functional changes.
This patch was created via this shell script:
for i in $(find drivers/media -name '*.[ch]' -type f) $(find drivers/staging/media -name '*.[ch]' -type f) $(find include/ -name '*.h' -type f) ; do sed s,media_entity_create_link,media_create_pad_link,g <$i >a && mv a $i; done
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
It helps to check if the media controller is doing the
right thing with the object creation and removal.
No extra code/data will be produced if DEBUG or
CONFIG_DYNAMIC_DEBUG is not enabled.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Just like entities and pads, links also need to have unique
Object IDs along a given media controller.
So, let's add a media_gobj inside it and initialize
the object then a new link is created.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
PADs also need unique object IDs that won't conflict with
the entity object IDs.
The pad objects are currently created via media_entity_init()
and, once created, never change.
While this will likely change in the future in order to
support dynamic changes, for now we'll keep PADs as arrays
and initialize the media_gobj embedded structs when
registering the entity.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
As entities are graph objects, let's embed media_gobj
on it. That ensures an unique ID for entities that can be
global along the entire media controller.
For now, we'll keep the already existing entity ID. Such
field need to be dropped at some point, but for now, let's
not do this, to avoid needing to review all drivers and
the userspace apps.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Due to the MC API proposed changes, we'll need to have an unique
object ID for all graph objects, and have some shared fields
that will be common on all media graph objects.
Right now, the only common object is the object ID, but other
fields will be added later on.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Instead of accessing directly entity.id, let's create a macro,
as this field will be moved into a common struct later on.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
