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path: root/drivers/media/video/v4l2-fh.c
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2012-08-13[media] v4l: move v4l2 core into a separate directoryMauro Carvalho Chehab
Currently, the v4l2 core is mixed together with other non-core drivers. Move them into a separate directory. Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-10-31drivers/media: Add export.h for EXPORT_SYMBOL/THIS_MODULE as requiredPaul Gortmaker
These two macros were in module.h but now module.h is no longer sprayed across every source file imaginable, so the users need to expicitly call out their use of them. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-07-27[media] v4l2-event/ctrls/fh: allocate events per fh and per type instead of ↵Hans Verkuil
just per-fh The driver had to decide how many events to allocate when the v4l2_fh struct was created. It was possible to add more events afterwards, but there was no way to ensure that you wouldn't miss important events if the event queue would fill up for that filehandle. In addition, once there were no more free events, any new events were simply dropped on the floor. For the control event in particular this made life very difficult since control status/value changes could just be missed if the number of allocated events and the speed at which the application read events was too low to keep up with the number of generated events. The application would have no idea what the latest state was for a control since it could have missed the latest control change. So this patch makes some major changes in how events are allocated. Instead of allocating events per-filehandle they are now allocated when subscribing an event. So for that particular event type N events (determined by the driver) are allocated. Those events are reserved for that particular event type. This ensures that you will not miss events for a particular type altogether. In addition, if there are N events in use and a new event is raised, then the oldest event is dropped and the new one is added. So the latest event is always available. This can be further improved by adding the ability to merge the state of two events together, ensuring that no data is lost at all. This will be added in the next patch. This also makes it possible to allow the user to determine the number of events that will be allocated. This is not implemented at the moment, but would be trivial. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27[media] v4l2-events/fh: merge v4l2_events into v4l2_fhHans Verkuil
Drivers that supported events used to be rare, but now that controls can also raise events this will become much more common since almost all drivers have controls. This means that keeping struct v4l2_events as a separate struct make no more sense. Merging it into struct v4l2_fh simplifies things substantially as it is now an integral part of the filehandle struct. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27[media] v4l2-ctrls: add control eventsHans Verkuil
Whenever a control changes value or state an event is sent to anyone that subscribed to it. This functionality is useful for control panels but also for applications that need to wait for (usually status) controls to change value. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27[media] v4l2-ioctl: add ctrl_handler to v4l2_fhHans Verkuil
This is required to implement control events and is also needed to allow for per-filehandle control handlers. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-03-22[media] v4l2: use new flag to enable core priority handlingHans Verkuil
Rather than guess which driver supports core priority handling, require drivers that do to explicitly set the V4L2_FL_USE_FH_PRIO flag in video_device. Updated the core prio handling accordingly and set the flag in the three drivers that do. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-03-22[media] v4l2-fh: add v4l2_fh_is_singularHans Verkuil
Several drivers need to do something when the first filehandle is opened or the last filehandle is closed. Most implement some use count mechanism, but if they use v4l2_fh, then you can also just check if this is the only filehandle for the device node. A simple helper function can do this. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-03-22[media] v4l2-fh: add v4l2_fh_open and v4l2_fh_release helper functionsHans Verkuil
Add two new functions: v4l2_fh_open allocates and initializes a struct v4l2_fh based on a struct file pointer and v4l2_fh_release releases and frees a struct v4l2_fh. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-03-22[media] v4l2-fh: implement v4l2_priority supportHans Verkuil
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19V4L/DVB: V4L: Events: Support event handling in do_ioctlSakari Ailus
Add support for event handling to do_ioctl. Signed-off-by: Sakari Ailus <sakari.ailus@maxwell.research.nokia.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19V4L/DVB: V4L: Events: Add backendSakari Ailus
Add event handling backend to V4L2. The backend handles event subscription and delivery to file handles. Event subscriptions are based on file handle. Events may be delivered to all subscribed file handles on a device independent of where they originate from. Signed-off-by: Sakari Ailus <sakari.ailus@maxwell.research.nokia.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19V4L/DVB: V4L: File handlesSakari Ailus
This patch adds a list of v4l2_fh structures to every video_device. It allows using file handle related information in V4L2. The event interface is one example of such use. The use of v4l2_fh is not mandatory for drivers. Signed-off-by: Sakari Ailus <sakari.ailus@maxwell.research.nokia.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>