If one device fails to enumerate, which isn't supposed to happen under
normal conditions, both the sysfs and the udev enumerators stop
enumeration of further devices. This potentially prevents working
devices from being detected and handled. Fix it by skipping the faulty
device.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Tested-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Now that our usage of C compatibility header is documented, use them
consistently through the source code.
While at it, group the C and C++ include statements as defined in the
coding style, and fix a handful of #include ordering issues.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Some media devices, such as V4L2 M2M devices, share the same device node
for multiple entities. The udev enumerator used to support this, but
commit 6e62034900 ("libcamera: device_enumerator: fix udev media graph
loading dependency") broke this.
To fix the problem, rework the media device to V4L2 devices matching
code. A new MediaDeviceDeps internal struct stores unmet device number
dependencies for a media device, and is stored in a list of pending
media devices. To avoid linear lookups, the dependencies are cached in a
reverse map of device number to media device dependencies.
Fixes: 6e62034900 ("libcamera: device_enumerator: fix udev media graph loading dependency")
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
DeviceEnumeratorUdev::populateMediaDevice() searches for orphan devices
in an std::list, and if found removes them using std::list::remove().
This ends up looking up the entry twice. Replace the remove() call with
erase() to fix it.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
When populating media devices, we look up device nodes for every entity
in the media device, regardless of if the entity is present in the
orphans list. This causes unnecessary lookups (that may also fail as the
device node may not be ready yet at that time). Move the lookup at a
later time, when the device node is actually needed.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
The lookupDeviceNode() method is declared as pure virtual in the base
DeviceEnumerator class, but is only called by derived classes. Move it
to the DeviceEnumeratorSysfs and DeviceEnumeratorUdev. This allows
changing the udev version to take a dev_t instead of separate
major/minor, as that's what both the caller and the callee end up using.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
When a MediaDevice is enumerated and populated by the
DeviceEnumeratorUdev, there is a possibility that the member device
nodes of the media graph would not be ready (either not created, or
without proper permissions set by udev yet). The MediaDevice is still
passed up to the pipeline handler, where an attempt to access the device
nodes will fail in EPERM. This whole issue is especially likely to
happen when libcamera is run at system init time.
To fix this, we first split DeviceEnumerator::addDevice() into three
methods:
- createDevice() to simply create the MediaDevice
- populateMediaDevice() to populate the MediaDevice
- addDevice() to pass the MediaDevice up to the pipeline handler
DeviceEnumeratorSysfs calls these methods in succession, similar to what
it did before when they were all together as addDevice().
DeviceEnumeratorUdev additionally keeps a map of MediaDevices to a list
of pending device nodes (plus some other auxillary maps), and a simple
list of orphan device nodes. If a v4l device node is ready and there
does not exist any MediaDevice node for it, then it goes to the orphan
list, otherwise it is initialized and removed from the pending list of
the corresponding MediaDevice in the dependency map. When a MediaDevice
is populated via DeviceEnumeratorUdev::populateMediaDevice(), it first
checks the orphan list to see if the device nodes it needs are there,
otherwise it tries to initialize the device nodes and if it fails, then
it adds the device nodes it wants to its list in the dependency map.
This allows MediaDevice instances to be created and initialized properly
with udev when v4l device nodes in the media graph may not be ready when
the MediaDevice is populated.
Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
libcamera depends on libudev for device enumeration. It is however
useful to allow building documentation without requiring the dependency
to be installed. Make the libudev dependency optional and compile the
udev-based device enumerator out when libudev is not present.
Note that while libcamera will compile without libudev, it will not be
able to enumerate devices. A sysfs-based device enumerator is planned as
a fallback but not implemented yet.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
