Commit Graph

255276 Commits (6d1724925d4da49b84161f1440912205576b7935)

Author SHA1 Message Date
Mauro Carvalho Chehab 6d1724925d [media] DocBook: Add a chapter to describe media errors
There are several errors reported by V4L that aren't described.
They can occur on almost all ioctl's. Instead of adding them
into each ioctl, create a new chapter.

For V4L, the new chapter will automatically be listed on all
places, as there's a macro used everywhere there.

Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:35 -03:00
Jonathan Corbet 28720944d8 [media] marvell-cam: use S/G DMA by default
Scatter/gather DMA mode works nicely on this platform and is clearly the
best way of doing things.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:35 -03:00
Jonathan Corbet cbc4f3a277 [media] marvell-cam: Working s/g DMA
The core Marvell camera driver can now do scatter/gather DMA on controllers
which support that functionality.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:35 -03:00
Hans Verkuil 60c0732244 [media] v4l2-ctrls.c: add support for V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK
Normally no control events will go to the filehandle that called the
VIDIOC_S_CTRL/VIDIOC_S_EXT_CTRLS ioctls. This is to prevent a feedback
loop.

This can now be overridden by setting the new V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK
flag.

Based on suggestions from Mauro Carvalho Chehab <mchehab@redhat.com> and
Laurent Pinchart <laurent.pinchart@ideasonboard.com>.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:34 -03:00
Hans Verkuil 3ad57c3384 [media] v4l2-event.h: add overview documentation to the header
It's getting confusing who is linking to what, so add an overview at
the start of the header.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:34 -03:00
Hans Verkuil 3f66f0ed31 [media] v4l2-ctrls/v4l2-events: small coding style cleanups
Thanks to Laurent Pinchart <laurent.pinchart@ideasonboard.com>.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:34 -03:00
Hans Verkuil e969084030 [media] DocBook: update V4L Event Interface section
Starting with v3.1 the V4L2 API provides certain guarantees with respect to
events. Document these.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:34 -03:00
Hans Verkuil 1de7310ac9 [media] v4l2-framework.txt: update v4l2_event section
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:33 -03:00
Hans Verkuil 98019f5e88 [media] v4l2-framework.txt: updated v4l2_fh_init documentation
v4l2_fh_init now returns void instead of int, updated the doc.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:33 -03:00
Hans Verkuil 71c6c4c918 [media] v4l2-ctrls: v4l2_ctrl_handler_setup code simplification
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:32 -03:00
Hans Verkuil e64025850d [media] v4l2-ctrls: split try_or_set_ext_ctrls()
Split try_or_set_ext_ctrls() into a validate_ctrls() part ('Phase 1')
and merge the second part ('Phase 2') into try_set_ext_ctrls().

This makes a lot more sense and it also does the validation before
trying to try/set the controls.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:32 -03:00
Hans Verkuil eb5b16efb2 [media] v4l2-ctrls: improve discovery of controls of the same cluster
The implementation of VIDIOC_G/S/TRY_EXT_CTRLS in the control framework has
to figure out which controls in the control list belong to the same cluster.
Since controls belonging to the same cluster need to be handled as a unit,
this is important information.

It did that by going over the controls in the list and for each control that
belonged to a multi-control cluster it would walk the remainder of the list
to try and find controls that belong to that same cluster.

This approach has two disadvantages:

1) it was a potentially quadratic algorithm (although highly unlikely that
it would ever be that bad in practice).
2) it took place with the control handler's lock held.

Since we want to make it possible in the future to change control values
from interrupt context, doing a lot of work while holding a lock is not a
good idea.

In the new code the algorithm is no longer quadratic but linear in the
number of controls in the list. Also, it now can be done beforehand.

Another change that was made was to so the try and set at the same time.
Before when S_TRY_EXT_CTRLS was called it would 'try' the controls first,
and then it would 'set' them. The idea was that any 'try' errors would
prevent the 'set' from happening, thus avoiding having partially set
control lists.

However, this caused more problems than it solved because between the 'try'
and the 'set' changes might have happened, so it had to try a second time,
and since actual controls with a try_ctrl op are very rare (and those that
we have just adjust values and do not return an error), I've decided to
drop that two-stage approach and just combine try and set.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:31 -03:00
Hans Verkuil c12fcfd676 [media] v4l2-ctrls: don't initially set CH_VALUE for write-only controls
When sending the SEND_INITIAL event for write-only controls the
V4L2_EVENT_CTRL_CH_VALUE flag should not be set. It's meaningless.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:31 -03:00
Hans Verkuil 2151bdc887 [media] v4l2-event: add optional merge and replace callbacks
When the event queue for a subscribed event is full, then the oldest
event is dropped. It would be nice if the contents of that oldest
event could be merged with the next-oldest. That way no information is
lost, only intermediate steps are lost.

This patch adds optional replace() (called when only one kevent was allocated)
and merge() (called when more than one kevent was allocated) callbacks that
will be called to do this job.

These two callbacks are implemented for the V4L2_EVENT_CTRL event.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:31 -03:00
Hans Verkuil f1e393de38 [media] v4l2-event/ctrls/fh: allocate events per fh and per type instead of 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 17:53:31 -03:00
Hans Verkuil 77068d36d8 [media] v4l2-ctrls/event: remove struct v4l2_ctrl_fh, instead use v4l2_subscribed_event
The v4l2_ctrl_fh struct connected v4l2_ctrl with v4l2_fh so the control
would know which filehandles subscribed to it. However, it is much easier
to use struct v4l2_subscribed_event directly for that and get rid of that
intermediate struct.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:31 -03:00
Hans Verkuil 523f46d6ab [media] v4l2-events/fh: merge v4l2_events into v4l2_fh
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 17:53:31 -03:00
Andrew Chew 95904d4b6a [media] V4L: ov9740: Add suspend/resume
On suspend, remember whether we are streaming or not, and at what frame format,
so that on resume, we can start streaming again.

Signed-off-by: Andrew Chew <achew@nvidia.com>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:30 -03:00
Andrew Chew e29c9bfb38 [media] V4L: ov9740: Reorder video and core ops
This is to avoid needing a forward declaration when ov9740_s_power() (in the
subsequent patch) calls ov9740_s_fmt().

Signed-off-by: Andrew Chew <achew@nvidia.com>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:29 -03:00
Andrew Chew 970aa9e04e [media] V4L: ov9740: Remove hardcoded resolution regs
Derive resolution-dependent register settings programmatically.

Signed-off-by: Andrew Chew <achew@nvidia.com>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:27 -03:00
Andrew Chew c4fdce5696 [media] V4L: ov9740: Fixed some settings
Based on vendor feedback, should issue a software reset at start of day.

Also, OV9740_ANALOG_CTRL15 needs to be changed so the sensor does not begin
streaming until it is ready (otherwise, results in a nonsense frame for the
initial frame).

Added a comment on using discontinuous clock.

Finally, OV9740_ISP_CTRL19 needs to be changed to really use YUYV ordering
(the previous value was for VYUY).

Signed-off-by: Andrew Chew <achew@nvidia.com>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:27 -03:00
Andrew Chew 5fec8b9002 [media] V4L: ov9740: Correct print in ov9740_reg_rmw()
The register width of the ov9740 is 16-bits, so correct the debug print
to reflect this.

Signed-off-by: Andrew Chew <achew@nvidia.com>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:25 -03:00
Andrew Chew c6aac9fcdd [media] V4L: ov9740: Cleanup hex casing inconsistencies
Made all hex number casing use lower-case throughout the entire driver
for consistency.

Signed-off-by: Andrew Chew <achew@nvidia.com>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:24 -03:00
Josh Wu 195ebc43bf [media] V4L: at91: add Atmel Image Sensor Interface (ISI) support
This patch is to enable Atmel Image Sensor Interface (ISI) driver support.

Signed-off-by: Josh Wu <josh.wu@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:23 -03:00
Guennadi Liakhovetski 8318a64b89 [media] V4L: soc-camera: remove several now unused soc-camera client operations
This patch removes .enum_input(), .suspend() and .resume() soc-camera
client operations.

Functionality, provided by .enum_input(), if needed, can be implemented
using the v4l2-subdev API.

As for .suspend() and .resume(), the only client driver, implementing
these methods has been mt9m111, and the only host driver, using them
has been pxa-camera. Now that both those drivers have been converted
to the standard subdev .s_power() operation, .suspend() and .resume()
can be removed.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:23 -03:00
Guennadi Liakhovetski 14c5ea9bb4 [media] V4L: mt9m111: switch to v4l2-subdev .s_power() method
Eliminate soc-camera specific .suspend() and .restore() methods in favour
of the standard v4l2-subdev .s_power() method

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:22 -03:00
Guennadi Liakhovetski 2768cbbba3 [media] V4L: mt9m111: propagate higher level abstraction down in functions
It is more convenient to propagate the higher level abstraction - the
struct mt9m111 object into functions and then retrieve a pointer to
the i2c client, if needed, than to do the reverse.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:22 -03:00
Guennadi Liakhovetski b7ccdba02a [media] V4L: soc-camera: MIPI flags are not sensor flags
SOCAM_MIPI_[1234]LANE flags are not board-specific sensor flags, they
are bus configuration flags.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:22 -03:00
Guennadi Liakhovetski 4df4ada936 [media] V4L: tw9910: remove bogus ENUMINPUT implementation
tw9910 is a TV decoder, it doesn't have a tuner. Besides, the
.enum_input soc-camera operation is optional and normally not needed.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:22 -03:00
Guennadi Liakhovetski ff391d71bc [media] V4L: sh_mobile_ceu_camera: remove redundant calculations
soc_camera core now performs the standard .bytesperline and .sizeimage
calculations internally, no need to duplicate in drivers.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:22 -03:00
Guennadi Liakhovetski 28281a71eb [media] V4L: mx2_camera: .try_fmt shouldn't fail
If the user is requesting too large a frame, instead of failing
select an acceptable geometry, preserving the requested aspect ratio.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:22 -03:00
Guennadi Liakhovetski 497833c681 [media] V4L: pxa-camera: switch to using subdev .s_power() core operation
soc-camera specific .suspend() and .resume() methods are deprecated
and should be replaced by the subdev standard .s_power() operation.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:21 -03:00
Guennadi Liakhovetski 91401219c0 [media] V4L: pxa-camera: try to force progressive video format
The pxa-camera driver only supports progressive video so far. Passing
down to the client the same format, as what the user has requested can
result in interlaced video, even if the client supports both. This
patch avoids such cases.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:21 -03:00
Guennadi Liakhovetski a5c1cee0e6 [media] V4L: pxa_camera: remove redundant calculations
soc_camera core now performs the standard .bytesperline and .sizeimage
calculations internally, no need to duplicate in drivers.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:21 -03:00
Guennadi Liakhovetski 6523208758 [media] V4L: mx3_camera: remove redundant calculations
soc_camera core now performs the standard .bytesperline and .sizeimage
calculations internally, no need to duplicate in drivers.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:21 -03:00
Hans Verkuil 82a7c04944 [media] v4l2-ctrls: make manual_mode_value 8 bits and check against control range
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:21 -03:00
Hans Verkuil 2330fb8242 [media] v4l2-compat-ioctl32: add VIDIOC_DQEVENT support
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:20 -03:00
Hans Verkuil 5138870d68 [media] ivtv: add control event support
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:20 -03:00
Hans Verkuil c7a52f8dce [media] vivi: support control events
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:20 -03:00
Hans Verkuil 85724983c4 [media] V4L2 spec: document control events
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:20 -03:00
Hans Verkuil ce7275747b [media] v4l2-ctrls: simplify event subscription
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:20 -03:00
Hans Verkuil 6e239399e5 [media] v4l2-ctrls: add control events
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 17:53:20 -03:00
Hans Verkuil ab892bac84 [media] v4l2-ctrls: add v4l2_fh pointer to the set control functions
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: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:19 -03:00
Hans Verkuil a1c894fba3 [media] vivi: add autogain/gain support to test the autocluster functionality
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:19 -03:00
Hans Verkuil c76cd63572 [media] Documentation: Improve cluster documentation and document the new autoclusters
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:19 -03:00
Hans Verkuil 72d877cac0 [media] v4l2-ctrls: add v4l2_ctrl_auto_cluster to simplify autogain/gain scenarios
It is a bit tricky to handle autogain/gain type scenerios correctly. Such
controls need to be clustered and the V4L2_CTRL_FLAG_UPDATE should be set on
the autofoo controls. In addition, the manual controls should be marked
inactive when the automatic mode is on, and active when the manual mode is on.
This also requires specialized volatile handling.

The chances of drivers doing all these things correctly are pretty remote.
So a new v4l2_ctrl_auto_cluster function was added that takes care of these
issues.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:18 -03:00
Hans Verkuil 78866efe8a [media] v4l2-controls.txt: update to latest v4l2-ctrl.c changes
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:17 -03:00
Hans Verkuil ddac5c1079 [media] v4l2-ctrls: fix and improve volatile control handling
If you have a cluster of controls that is a mix of volatile and non-volatile
controls, then requesting the value of the volatile control would fail if the
master control of that cluster was non-volatile. The code assumed that the
volatile state of the master control was the same for all other controls in
the cluster.

This is now fixed.

In addition, it was clear from bugs in some drivers that it was confusing that
the ctrl->cur union had to be used in g_volatile_ctrl. Several drivers used the
'new' values instead. The framework was changed so that drivers now set the new
value instead of the current value.

This has an additional benefit as well: the volatile values are now only stored
in the 'new' value, leaving the current value alone. This is useful for
autofoo/foo control clusters where you want to have a 'foo' control act like a
volatile control if 'autofoo' is on, but as a normal control when it is off.

Since with this change the cur value is no longer overwritten when g_volatile_ctrl
is called, you can use it to remember the original 'foo' value. For example:

autofoo = 0, foo = 10 and foo is non-volatile.

Now autofoo is set to 1 and foo is marked volatile. Retrieving the foo value
will get the volatile value. Set autofoo back to 0, which marks foo as non-
volatile again, and retrieving foo will get the old current value of 10.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:17 -03:00
Hans Verkuil 18d171badf [media] v4l2-subdev: implement per-filehandle control handlers
To be consistent with v4l2-ioctl.c.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:53:17 -03:00
Hans Verkuil 2d28b686ad [media] v4l2-ioctl: add ctrl_handler to v4l2_fh
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>
2011-07-27 17:53:17 -03:00