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  1. 28 7月, 2011 4 次提交
    • H
      [media] v4l2-event/ctrls/fh: allocate events per fh and per type instead of just per-fh · f1e393de
      由 Hans Verkuil 提交于 
      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: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>
      f1e393de
    • H
      [media] v4l2-events/fh: merge v4l2_events into v4l2_fh · 523f46d6
      由 Hans Verkuil 提交于 
      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: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>
      523f46d6
    • H
      [media] v4l2-ctrls: add v4l2_fh pointer to the set control functions · ab892bac
      由 Hans Verkuil 提交于 
      When an application changes a control you want to generate an event.
However, you want to avoid sending such an event back to the application
(file handle) that caused the change.

Add the filehandle to the various set control functions.

The filehandle isn't used yet, but the control event patches will need
this.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>
      ab892bac
    • H
      [media] v4l2-subdev: implement per-filehandle control handlers · 18d171ba
      由 Hans Verkuil 提交于 
      To be consistent with v4l2-ioctl.c.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>
      18d171ba
  3. 05 5月, 2011 1 次提交
  5. 22 3月, 2011 11 次提交
  7. 07 4月, 2009 1 次提交
  9. 30 3月, 2009 3 次提交
  11. 29 1月, 2009 1 次提交
  13. 03 1月, 2009 1 次提交
  15. 30 12月, 2008 2 次提交