The BKL replacement mutex had some serious performance side-effects on
V4L drivers. It is replaced by a better heuristic that works around the
worst of the side-effects.
Read the v4l2-dev.c comments for the whole sorry story. This is a
temporary measure only until we can convert all v4l drivers to use
unlocked_ioctl.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Where reasonable use mutex_lock_interruptible instead of mutex_lock.
Also fix the poll, read and write error codes when called with an unregistered
device (e.g. after a USB device was disconnected). Poll must return
POLLERR|POLLHUP and read/write must return -ENODEV.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
All of the hard problems for BKL removal appear to be solved in the
v4l-dvb/master tree. This removes the BKL from the various open
functions that do not need it, or only use it to protect an
open count.
The zoran driver is nontrivial in this regard, so I introduce
a new mutex that locks both the open/release and the ioctl
functions. Someone with access to the hardware can probably
improve that by using the existing lock in all cases.
Finally, all drivers that still use the locked version of the
ioctl function now get called under a new mutex instead of
the BKL.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Drivers can optionally set a pointer to a mutex in struct video_device.
The core will use that to lock before calling open, read, write, unlocked_ioctl,
poll, mmap or release.
Updated the documentation as well and ensure that v4l2-event knows about the
lock: it will unlock it before doing a blocking wait on an event and relock it
afterwards.
Ensure that the 'video_is_registered' check is done when the lock is held:
a typical disconnect will take the lock as well before unregistering the
device nodes, so to prevent race conditions the video_is_registered check
should also be done with the lock held.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Until now all fops except release and (unlocked_)ioctl returned an error
after the device node was unregistered. Extend this as well to the ioctl
fops. There is nothing useful that an application can do here and it
complicates the driver code unnecessarily.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Remove the vtx (aka videotext aka teletext) API from the v4l2 core.
This API was scheduled for removal in kernel 2.6.35.
The vtx device nodes have been superseded by vbi device nodes
for many years. No applications exist that use the vtx support.
Of the two i2c drivers that actually support this API the saa5249
has been impossible to use for a year now and no known hardware
that supports this device exists. The saa5246a is theoretically
supported by the old mxb boards, but it never actually worked.
In summary: there is no hardware that can use this API and there
are no applications actually implementing this API.
The vtx support still reserves minors 192-223 and we would really
like to reuse those for upcoming new functionality. In the unlikely
event that new hardware appears that wants to use the functionality
provided by the vtx API, then that functionality should be build
around the sliced VBI API instead.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (94 commits)
V4L/DVB: tvp7002: fix write to H-PLL Feedback Divider LSB register
V4L/DVB: dvb: siano: free spinlock before schedule()
V4L/DVB: media: video: pvrusb2: remove custom hex_to_bin()
V4L/DVB: drivers: usbvideo: remove custom implementation of hex_to_bin()
V4L/DVB: Report supported QAM modes on bt8xx
V4L/DVB: media: ir-keytable: null dereference in debug code
V4L/DVB: ivtv: convert to the new control framework
V4L/DVB: ivtv: convert gpio subdev to new control framework
V4L/DVB: wm8739: convert to the new control framework
V4L/DVB: cs53l32a: convert to new control framework
V4L/DVB: wm8775: convert to the new control framework
V4L/DVB: cx2341x: convert to the control framework
V4L/DVB: cx25840: convert to the new control framework
V4L/DVB: cx25840/ivtv: replace ugly priv control with s_config
V4L/DVB: saa717x: convert to the new control framework
V4L/DVB: msp3400: convert to the new control framework
V4L/DVB: saa7115: convert to the new control framework
V4L/DVB: v4l2: hook up the new control framework into the core framework
V4L/DVB: Documentation: add v4l2-controls.txt documenting the new controls API
V4L/DVB: v4l2-ctrls: Whitespace cleanups
...
Add the calls needed to automatically merge subdev controls into a bridge
control handler.
Hook up the control framework in __video_ioctl2 and video_register_device.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
v4l2 implements two separate file operations for drivers that
use locked and unlocked ioctl callbacks. Since we want to remove
the ioctl file operation in favor of the unlocked variant, this
separation no longer seems helpful.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: Hans Verkuil <hverkuil@xs4all.nl>
Cc: John Kacur <jkacur@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Since commit b402843787
the 'driver_data' field resides in device's struct device_private
which may be allocated by dev_set_drvdata() if device_private
struct was not allocated previously.
dev_set_drvdata() is used in video_set_drvdata() to set
the driver's private data pointer in v4l2 drivers. Setting
the private data _before_ registering the v4l2 device results
in a memory leak since __video_register_device() also calls
video_set_drvdata(), but after zeroing the device structure.
Thus, the reference to the previously allocated device_private
struct goes lost and a new device_private will be allocated.
All v4l drivers which call video_set_drvdata() _before_
calling video_register_device() are affected. The patch fixes
__video_register_device() to preserve previously allocated
device_private reference.
Caught by kmemleak.
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
No need to lock when unregistering the device: clear_bit is already an
atomic operation.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
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>
Replace the video_is_unregistered function by a video_is_registered
function. The V4L2_FL_UNREGISTERED flag is replaced by a
V4L2_FL_REGISTERED flag.
This change makes the video_is_registered function return coherent
results when called on an initialize but not yet registered video_device
instance. The function can now be used instead of checking
video_device::minor.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Many drivers access the device number (video_device::v4l2_devnode::num)
in order to print the video device node name. Add and use a helper
function to retrieve the video_device node name.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Warn when the desired device node number is already in use, except when
the new video_register_device_no_warn function is called since in some
use-cases that warning is not relevant.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
There are some subtle differences in the way the devnode numbers are
handled depending on whether the FIXED_MINOR_RANGES config option is
set. Add some simple wrapper functions to handle that correctly.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
The term 'kernel number' is very vague, so replace it with the somewhat more
descriptive term 'device node number'.
In one place the local variable 'nr' was used to create the device node number
of the new device name. This has been replaced with the vdev->num field to
more clearly mark this as being the device node number and not the minor
number.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
video_register_device_index is never actually called, instead the
stream index number is always calculated automatically.
This patch removes this function and simplifies the internal get_index
function since that can now always just return the first free index.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT
This will make hardirq.h inclusion cheaper for every PREEMPT=n config
(which includes allmodconfig/allyesconfig, BTW)
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch allows v4l2_open and v4l2_release functions return 0 if open and
release driver callbacks set to NULL. This will be used in radio
drivers.
--
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Alexey Klimov <klimov.linux@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Shared memory mappings on nommu machines require a get_unmapped_area
file operation that suggests an address for the mapping. This patch
adds a way for v4l2 drivers to provide this callback.
Signed-off-by: Daniel Glöckner <dg@emlix.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Normally the parent device of v4l2_device is used as the video device
node's parent. But if it was not set, then use the parent field in the
video_device struct.
This is needed in the cx88 driver, which has one core v4l2_device but
creates multiple pci devices (one each for raw and mpeg video).
So you cannot associate the core v4l2_device with a particular PCI device,
but you can do that for each video_device.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
The videodev module is missing the char-major-81-* alias that would
cause it to be auto-loaded when a device of that type is opened. This
patch adds the alias.
Signed-off-by: Scott James Remnant <scott@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
video_register_device_index() checks if it was passed a NULL video_device
pointer (which isn't allowed) _after_ it has already dereferenced it with
video_get_drvdata(vdev). The checks are clearly pointless and can be
removed, as the function would have crashed before reaching them if vdev
ever was NULL.
Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
get_index() had a limitation of 32 devices per driver. This was
unnecessarily strict and has been replaced with the maximum number
of devices. That should really satisfy anyone!
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This rename prevents conflicts with the older compat_ioctl32 module.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Introduce a struct v4l2_file_operations for v4l2 drivers.
Remove the unnecessary inode argument.
Move compat32 handling (and llseek) into the v4l2-dev core: this is now
handled in the v4l2 core and no longer in the drivers themselves.
Note that this changeset reverts an earlier patch that changed the return
type of__video_ioctl2 from int to long. This change will be reinstated
later in a much improved version.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Drivers that use v4l2_device can set that as parent pointer in the v4l2_dev
field instead of using the struct device parent field.
This allows v4l2-dev.c to check whether this driver is v4l2_device based,
and if so then it can offer additional services.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Instead of relying on the cdev release callback we should rely on the
release callback from the device struct. This requires that we use
get_device/put_device to do proper refcounting. In order to do this
safely v4l2-dev.c now sets up its own file_operations that call
out to the driver's ops.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
get_index requires a valid parent device in order to discover which
indices are in use. Some drivers (e.g. pvrusb2) do not set the parent
device. In that case just return 0.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This patch is part of a larger patch series which will remove
the "char bus_id[20]" name string from struct device. The device
name is managed in the kobject anyway, and without any size
limitation, and just needlessly copied into "struct device".
To set and read the device name dev_name(dev) and dev_set_name(dev)
must be used. If your code uses static kobjects, which it shouldn't
do, "const char *init_name" can be used to statically provide the
name the registered device should have. At registration time, the
init_name field is cleared, to enforce the use of dev_name(dev) to
access the device name at a later time.
We need to get rid of all occurrences of bus_id in the entire tree
to be able to enable the new interface. Please apply this patch,
and possibly convert any remaining remaining occurrences of bus_id.
We want to submit a patch to -next, which will remove bus_id from
"struct device", to find the remaining pieces to convert, and finally
switch over to the new api, which will remove the 20 bytes array
and does no longer have a size limitation.
Thanks,
Kay
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
The v4l core creates four different video devices (video, vbi, radio, vtx)
and each has its own range of minor numbers. However, modern devices keep
increasing the number of devices that they need so a maximum of 64 video
devices will not be enough in the future. In addition this scheme makes
it very hard to add new device types.
This patch disconnects the kernel number allocation (e.g. video0, video1,
etc.) from the actual minor number (just pick the first free minor).
This allows for much more flexibility in the future. However, it does
require the use of udev. For those who cannot use udev a new CONFIG option
was created that changes the allocation scheme back to the old behavior.
Thanks to Greg KH for suggesting this approach during the 2008 LPC.
In addition, several bugs were fixed in the ivtv and cx18 drivers: these
drivers try to allocate specific kernel numbers but that scheme contained
a bug which caused what should have been e.g. video17 to appear as e.g.
video2.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Replace the old register_chrdev with the more flexible register_chrdev_region.
Ensure that the release() is called when the very last chardev usage was
released, and not when the sysfs devices were removed. This should simplify
hotpluggable drivers considerably.
Tested-by: Mike Isely <isely@isely.net>
Tested-by: Laurent Pinchart <laurent.pinchart@skynet.be>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Acked-by: David Ellingsworth <david@identd.dyndns.org>
Reviewed-by: Hans de Goede <j.w.r.degoede@hhs.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
The driver_data field of the device structure was zeroed, thus losing
this information. Many drivers set this up before calling
video_device_register, so we have to ensure that it isn't lost.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Cleanup v4l2-dev.[ch], add/improve comments and add a new helper
function: video_drvdata() that can get the private driver data from
a file struct.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Now that all drivers set the release callback in the video_device
struct we can put in a BUG_ON in video_register_device to ensure that
the callback is always there.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Add a second release function: video_device_release_empty
It can be used by drivers that have statically allocated
video_device structs.
Its use usually, but not always, indicates laziness on the
part of the driver programmer.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Better check the video_device pointer before using it.
Signed-off-by: Henrik Kretzschmar <henne@nachtwindheim.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
The BKL is now moved from the video_open function in v4l2-dev.c to the
various drivers. It seems about a third of the drivers already has a
lock of some sort protecting the open(), another third uses
video_exclusive_open (yuck!) and the last third required adding the
BKL in their open function.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Better check the video_device pointer before using it.
Signed-off-by: Henrik Kretzschmar <henne@nachtwindheim.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
If a wrong device type is used with video_register_device_index() it should
better return an error number, instead of a constant.
Signed-off-by: Henrik Kretzschmar <henne@nachtwindheim.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Change function name in kernel-doc and add kernel-doc for parameter @index:
Warning(linhead//drivers/media/video/videodev.c:2090): No description found for parameter 'index'
Also change source file name in DocBook/videobook.tmpl to match the new
source file name.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
The type and type2 fields were unused and so could be removed.
Instead add a vfl_type field that contains the type of the video
device.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
The class_dev field is a normal device, not a class device. This is very
confusing and now that the old 'dev' field has been renamed to 'parent'
we can rename 'class_dev' to just 'dev'.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
