Commit Graph

187 Commits

Author SHA1 Message Date
Hans de Goede 4a82bc60a9 [media] gspca_main: Update buffer flags even when user_copy fails
Before this patch dqbuf errors out on a failing user_copy (with user pointers)
before updating the buffer flags, causing a successsfully dequeued buffer
to still have the DONE flag, which means that it could no longer be
re-queueud (assuming the app somehow survives the segfault).

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-01-19 11:44:55 -02:00
Hans de Goede 27074efa2e [media] gspca_main: Locking fixes 2
Before this patch vidioc_dqbuf is using its own read_lock, where as
other queue related functions use queue_lock. This means that dqbuf is
accessing several variables in a racy manor. The most important one
being fr_o, which may be changed from underneath dqbuf by vidioc_reqbufs
or vidioc_streamoff. Other variables which it accesses unprotected
are gspca_dev->memory, gspca_dev->streaming and gspca_dev->capt_file.

This patch fixes this by changing vidioc_dqbuf to also use the queue_lock.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-01-19 11:44:54 -02:00
Hans de Goede 4e770f7602 [media] gspca_main: Locking fixes 1
The gspca_dev->streaming boolean is protected against multiple access
through gspca_dev->queue_lock everywhere except for 2 places. This patch
fixes this by bringing it under the lock in vidioc_streamoff. And by
removing the check for gspca_dev->streaming in gspca_disconnect,
the destroy_urbs call may be called multiple times (and is protected
by the usb_lock) and calling wake_up_interruptible can also always be done
safely.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-01-19 11:44:53 -02:00
Jean-François Moine d85185902f [media] gspca - main: Fix some warnings
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-12-29 08:17:19 -02:00
Mauro Carvalho Chehab 95f18be2e4 [media] gspca: Fix a warning for using len before filling it
The check for status errors is now before the check for len. That's
ok. However, the error printk's for the status error prints the URB
length. This generates this error:

drivers/media/video/gspca/gspca.c: In function ‘fill_frame’:
drivers/media/video/gspca/gspca.c:305:9: warning: ‘len’ may be used uninitialized in this function

The fix is as simple as moving the len init to happen before the checks.

Cc: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-12-29 08:17:14 -02:00
Jean-François Moine 668f44a603 [media] gspca: Use the global error status for get/set streamparm
Also, in ov534, don't check the parm type.

Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-12-29 08:17:06 -02:00
Jean-François Moine 76ebc16b87 [media] gspca - main: Check the isoc packet status before its length
When an error is set for an isochronous packet, the length of the packet
may be null. In this case, the error was not detected and the image
was not discarded as it should be.

Reported-by: Franck Bourdonnec <fbourdonnec@chez.com>
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-12-29 08:17:06 -02:00
Mauro Carvalho Chehab d4b416f262 [media] gspca core: Fix regressions gspca breaking devices with audio
Changeset 35680ba broke several devices:
	- Sony Playstation Eye (1415:2000);
	- Gigaware model 25-234 (0c45:628f);
	- Logitech Messenger Plus (046d:08f6).

Probably more devices were broken by this change.

What happens is that several devices don't need to save some bandwidth
for audio.

Also, as pointed by Hans de Goede <hdegoede@redhat.com>, the logic
that implements the bandwidth reservation for audio is broken, since
it will reduce the alt number twice, on devices with audio.

So, let's just revert the broken logic, and think on a better solution
for usb 1.1 devices with audio that can't use the maximum packetsize.

Acked-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-12-29 08:16:59 -02:00
Jean-François Moine a23c1947f4 [media] gspca - main: Fix a small code error
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-12-29 08:16:32 -02:00
Jean-François Moine 0b8851b6c3 [media] gspca - main: Version change
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-12-29 08:16:31 -02:00
Hans de Goede 2661da47da [media] gspca: only set gspca->int_urb if submitting it succeeds
Currently alloc_and_submit_int_urb() is setting gspca->int_urb
as soon as the allocation has succeeded, but if the subsequent
submit fails, the urb gets destroyed. And then later will
get destroyed again in gspca_input_destroy_urb() because
gspca->int_urb is set, leading to a double free.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-12-29 08:16:30 -02:00
Hans de Goede 314b3e0881 [media] gspca: submit interrupt urbs *after* isoc urbs
Currently gspca supported usb-1.1 webcams for which we support the input
button through an interrupt endpoint won't stream (not enough bandwidth
error) when used through an USB-2.0 hub.

After much debugging I've found out that the cause for this is that the
ehci-sched.c schedeling code does not like it when there are already urb's
scheduled when (large) isoc urbs are queued. By moving the submission
of the interrupt urbs to after submitting the isoc urbs the camera
starts working again through usb-2.0 hubs.

Note that this does not fix isoc. streaming through a usb-hub while another
1.1 usb device (like the microphone of the same cam) is also active
at the same time :(

I've spend a long time analyzing the linux kernel ehci scheduler code,
resulting in this (long) mail:
http://www.spinics.net/lists/linux-usb/msg37982.html

The conclusion of the following mail thread is that yes there are several
issues when using usb-1.1 devices through a usb-2.0 hub, but these are not
easily fixable in the current code. Fixing this in ehci-sched.c requires
an almost full rewrite, which is not bound to happen anytime soon.

So with this patch gspca driven usb-1.1 webcams will atleast work when
connected through an usb-2.0 hub when the microphone is not used.

As an added bonus this patch avoids extra destroy/create input urb cycles
when we end up falling back to a lower speed alt setting because of bandwidth
limitations.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-12-29 08:16:30 -02:00
Jean-François Moine 780e312175 [media] gspca: Fix coding style issues
The errors were found by checkpatch.pl. Most fixes are:
- remove spaces followed by TAB(s),
- split lines greater than 80 characters,
- move most '{'s from start of line to end of previous line.
  (Some '{'s at start of line remain when the '}'s are on the same line)

Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-10-21 14:50:06 -02:00
Jean-François Moine f43402fa55 [media] gspca - main: Fix a regression with the PS3 Eye webcam
When audio is present, some alternate settings were skipped.
This prevented some webcams to work, especially when bulk transfer was used.
This patch permits to use the last or only alternate setting.

Reported-by: Antonio Ospite <ospite@studenti.unina.it>
Tested-by: Antonio Ospite <ospite@studenti.unina.it>
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-10-21 08:56:41 -02:00
Jean-François Moine 2e0544a8ac [media] gspca - main: Have discontinuous sequence numbers when frames are lost
This patch also sets to 0 the sequence of the first frame.

Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-10-21 07:55:51 -02:00
Jean-François Moine 6a33091f13 [media] gspca - main: New video control mechanism
The new control mechanism uses dynamic control values in the subdriver
descriptor. It simplifies standard control handling.

Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-10-21 01:18:27 -02:00
Jean-François Moine 0b656321f3 V4L/DVB: gspca - all modules: Display error messages when gspca debug disabled
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-10-21 01:05:53 -02:00
Jean-François Moine 548264375b V4L/DVB: gspca - all modules: Remove useless module load/unload messages
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-10-21 01:05:52 -02:00
Jason Wang 882787ff8f V4L/DVB: gspca - main: Fix a crash of some webcams on ARM arch
When plugging some webcams on ARM, the system crashes.
This is because we alloc buffer for an urb through usb_buffer_alloc,
the alloced buffer is already in DMA coherent region, so we should
set the flag of this urb to URB_NO_TRANSFER_DMA_MAP, otherwise when
we submit this urb, the hcd core will handle this address as an
non-DMA address and call dma_map_single/sg to map it. On arm
architecture, dma_map_single a DMA coherent address will be catched
by a BUG_ON().

Signed-off-by: Jason Wang <jason77.wang@gmail.com>
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Cc: stable@kernel.org
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-09-27 22:21:51 -03:00
Jean-François Moine fe988f56c7 V4L/DVB: gspca - main: Fix a crash in gspca_frame_add()
Some webcams as ov511 may find many times an end of image.
In this case, with the last patch in image concatenation
(commit 799b1bd41f398054d46fd35f73abd01c4009f6ca),
the image pointer was NULL and the system crashed in memcpy().

Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-08 23:43:01 -03:00
Jean-François Moine 30d4554a02 V4L/DVB: gspca - main: Version change
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-08 23:42:52 -03:00
Jean-François Moine 35680baa68 V4L/DVB: gspca - main: Handle the audio device
When there is an audio device, use a lower alternate setting.
This patch does not fix correctly all audio and bandwidth problems.

Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-02 16:43:06 -03:00
Jean-François Moine c4dc692ce6 V4L/DVB: gspca - main: Adjust and remove some debug messages
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-02 16:43:05 -03:00
Jean-François Moine a4f96eb2b1 V4L/DVB: gspca - main: Remove useless audio ioctl's
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-02 16:43:04 -03:00
Jean-François Moine a2ba6f27cd V4L/DVB: gspca - main: Fix a compilation warning
Reported-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-02 16:43:02 -03:00
Jean-François Moine f7059eaa28 V4L/DVB: gspca - main: Don't use the frame buffer flags
This patch fixes possible race conditions in queue management with SMP:
when a frame was completed, the irq function tried to use the next frame
buffer. At this time, it was possible that the application on an other
processor updated the frame pointer, making the image to point to a bad
buffer.
The patch contains two main changes:
- the image transfer uses the queue indexes which are protected against
  simultaneous memory access,
- the image pointer which is used for image concatenation is only set at
  interrupt level.
Some subdrivers which used the image pointer have been updated.

Reported-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-02 16:42:48 -03:00
Jean-François Moine 02bbcb9d86 V4L/DVB: gspca - main: Possible race condition in queue management
The problem may occur with SMP:
- a frame is completed at interrupt level (in gspca_frame_add with
  packet_type == LAST_PACKET,
- just after clearing the bit V4L2_BUF_FLAG_QUEUED and before setting
  the bit V4L2_BUF_FLAG_DONE, on the other processor, the application
  tries to requeue the same frame buffer,
- then, the qbuf function succeeds because ALL_FLAGS are not set.
The fix sets and resets the two flags in one instruction.

Reported-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-02 16:42:47 -03:00
Jean-François Moine b192ca9837 V4L/DVB: gspca - main: Simplify image building
The image pointer and its length are now in the main structure instead
of in the frame buffer. They are updated on application vidioc_qbuf and
in the URB interrupt function when ending an image.

Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-02 15:31:10 -03:00
Jean-François Moine 38bff697ac V4L/DVB: gspca - main: Remove V4L1 compatibility
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-02 14:52:36 -03:00
Jean-François Moine e795d912d7 V4L/DVB: gspca - main: Don't use the PG_Reserved flag for mmapped buffers
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-02 14:52:20 -03:00
Jean-François Moine 4462864d72 V4L/DVB: gspca - main: Function gspca_dev_probe2 added
This function is used when the USB video interface is checked by
the subdriver.

Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-02 14:44:56 -03:00
Linus Torvalds 7a9b149212 Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: (229 commits)
  USB: remove unused usb_buffer_alloc and usb_buffer_free macros
  usb: musb: update gfp/slab.h includes
  USB: ftdi_sio: fix legacy SIO-device header
  USB: kl5usb105: reimplement using generic framework
  USB: kl5usb105: minor clean ups
  USB: kl5usb105: fix memory leak
  USB: io_ti: use kfifo to implement write buffering
  USB: io_ti: remove unsused private counter
  USB: ti_usb: use kfifo to implement write buffering
  USB: ir-usb: fix incorrect write-buffer length
  USB: aircable: fix incorrect write-buffer length
  USB: safe_serial: straighten out read processing
  USB: safe_serial: reimplement read using generic framework
  USB: safe_serial: reimplement write using generic framework
  usb-storage: always print quirks
  USB: usb-storage: trivial debug improvements
  USB: oti6858: use port write fifo
  USB: oti6858: use kfifo to implement write buffering
  USB: cypress_m8: use kfifo to implement write buffering
  USB: cypress_m8: remove unused drain define
  ...

Fix up conflicts (due to usb_buffer_alloc/free renaming) in
	drivers/input/tablet/acecad.c
	drivers/input/tablet/kbtab.c
	drivers/input/tablet/wacom_sys.c
	drivers/media/video/gspca/gspca.c
	sound/usb/usbaudio.c
2010-05-20 21:26:12 -07:00
Daniel Mack 997ea58eb9 USB: rename usb_buffer_alloc() and usb_buffer_free() users
For more clearance what the functions actually do,

  usb_buffer_alloc() is renamed to usb_alloc_coherent()
  usb_buffer_free()  is renamed to usb_free_coherent()

They should only be used in code which really needs DMA coherency.

All call sites have been changed accordingly, except for staging
drivers.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Pedro Ribeiro <pedrib@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-20 13:21:38 -07:00
Jean-François Moine b26d6e2178 V4L/DVB: gspca - main: Convert wMaxPacketSize from little endian 16 to cpu
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19 12:58:45 -03:00
Jean-François Moine e4dac289f0 V4L/DVB: gspca - main: Stop the webcam when bandwidth too small
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19 12:57:57 -03:00
Jean-François Moine 832d0a9130 V4L/DVB: gspca - main: Restart streaming after reqbuf
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19 12:57:56 -03:00
Jean-François Moine 18bf99aa0c V4L/DVB: gspca - main: Check the file doing stream on/off
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19 12:57:54 -03:00
Jean-François Moine 27c6f9e548 V4L/DVB: gspca: Change some copyrights and module authors
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19 12:57:34 -03:00
Randy Dunlap f76280154c V4L/DVB: [-next] gspca: fix build for INPUT=m or INPUT=n
Handle case of GSPCA=m, INPUT=m when building gspca core;
also handle case of INPUT=n by using stubs.

drivers/media/video/gspca/gspca.c:662: error: implicit declaration of function 'gspca_input_destroy_urb'
drivers/media/video/gspca/gspca.c:668: error: implicit declaration of function 'gspca_input_create_urb'
drivers/media/video/gspca/gspca.c:2284: error: implicit declaration of function 'gspca_input_connect'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19 12:57:30 -03:00
Mauro Carvalho Chehab d1875d6559 V4L/DVB: gspca: fixes compilation when input is not selected
It seems that I merged a wrong version of the patch or that
changeset 4d770eeb926d0bc44c0bd68d051d3d2a5568ef41 got mangled somehow:

It were missed the #else to avoid compilation troubles.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-18 00:50:21 -03:00
Paulo Assis 2f51d00ffa V4L/DVB: gspca - main: Use ktime instead of jiffies for buffer timestamping
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-18 00:46:30 -03:00
Hans de Goede e7637521ac V4L/DVB: gspca_main: Fix a compile error when CONFIG_INPUT is not set
gspca_main: Fix a compile error when CONFIG_INPUT is not set.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-02-26 15:11:10 -03:00
Hans de Goede 10ee240200 V4L/DVB: gspca_main: some input error handling fixes
2 small changes to input device error handling:
1) Make it fatal when we fail to create an input device (it is either this
   or add checks for gspca_dev->input_dev being NULL in a lot of places)
2) Since we allow gspca_input_create_urb() to fail everywhere we call it,
   and thus never check its return value, make it void.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-02-26 15:11:09 -03:00
Hans de Goede ac82f59f9c V4L/DVB: gspca_main: Allow use of input device creation code for non int. inputs
Allow use of the gspca core input device creation code by subdrivers which
have non interrupt driven camera buttons.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-02-26 15:11:09 -03:00
Hans de Goede 26984b0995 V4L/DVB: gscpa_sonixb: Differentiate between sensors with a coarse and fine expo ctrl
Some sensors only allow controlling the exposure by changing the clockdiv,
which means that exposure takes pretty large jumps (for example when going
from a div of 1 to 2, the exposure doubles). Use 2 different entries in
the controls array for these 2 different types of exposure (always
disabling one), and;

Add a new autogain algorithm for the coarse exposure case, which normally
changes the gain setting, only touching the exposure setting if the desired
luminance cannot be reached with gain, and after an exposure change once more
first tries gain, etc. Thus avoiding exposure changes, and the resulting
oscilation because of the huge steps these exposure controls take.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-02-26 15:11:08 -03:00
Jean-François Moine e070bf9ef8 V4L/DVB: gspca - main: Fix a compile error when CONFIG_INPUT is not set
Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-02-26 15:11:04 -03:00
Jean-François Moine 55461f4c58 V4L/DVB: gspca - main: Change version to 2.9.0.
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-02-26 15:10:49 -03:00
Márton Németh 0274d42e05 V4L/DVB: gspca - main: Add input support for interrupt endpoints.
Signed-off-by: Márton Németh <nm127@freemail.hu>
Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-02-26 15:10:49 -03:00
Jean-Francois Moine ab6c8cf21e V4L/DVB: gspca - main: Clear any previous USB error when starting the transfer
Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-02-26 15:10:47 -03:00
Jean-Francois Moine b7a597d110 V4L/DVB (13925): gspca - main: Change the check of the USB video interface.
Some webcams have many interfaces with the same interface class, so the
previous interface check did not work.
The new code checks if the interface number is zero or the only one.

Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-02-26 15:10:32 -03:00