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path: root/linux/drivers/media/video/videobuf-core.c
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2009-06-03buf-core.c: add pointer checkMauro Carvalho Chehab
From: Figo.zhang <figo1802@gmail.com> add poiter check for videobuf_queue_core_init(). any guys who write a v4l driver, pass a NULL pointer or a non-inintial pointer to the first parameter such as videobuf_queue_sg_init() , it would be crashed. Signed-off-by: Figo.zhang <figo1802@gmail.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-05-02V4L/DVB: cleanup redundant tests on unsignedMauro Carvalho Chehab
From: Roel Kluin <roel.kluin@gmail.com> Remove redundant tests on unsigned. Signed-off-by: Roel Kluin <roel.kluin@gmail.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-04-292: modify return value of VIDIOC_REQBUFS ioctlMauro Carvalho Chehab
From: Németh Márton <nm127@freemail.hu> The V4L2 ioctls usually return 0 when the operation was successful and -1 in case of error. Currently VIDIOC_REQBUFS returns the number of buffers which is redundant because this information is available in count field of struct v4l2_requestbuffers. The V4L2 API specification, revision 0.24 [1] explicitly specifies for VIDIOC_REQBUFS that the return value shall be 0 on success. The patch was tested with v4l-test 0.13 [2] with vivi driver. References: [1] V4L2 API specification, revision 0.24 http://v4l2spec.bytesex.org/spec/r13696.htm [2] v4l-test: Test environment for Video For Linux Two API http://v4l-test.sourceforge.net/ Signed-off-by: Márton Németh <nm127@freemail.hu> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2008-07-27backport commit 27ac792ca0b0a1e7e65f20342260650516c95864Mauro Carvalho Chehab
From: Mauro Carvalho Chehab <mchehab@infradead.org> kernel-sync: Author: Andrea Righi <righi.andrea@gmail.com> Date: Wed Jul 23 21:28:13 2008 -0700 PAGE_ALIGN(): correctly handle 64-bit values on 32-bit architectures On 32-bit architectures PAGE_ALIGN() truncates 64-bit values to the 32-bit boundary. For example: u64 val = PAGE_ALIGN(size); always returns a value < 4GB even if size is greater than 4GB. The problem resides in PAGE_MASK definition (from include/asm-x86/page.h for example): #define PAGE_SHIFT 12 #define PAGE_SIZE (_AC(1,UL) << PAGE_SHIFT) #define PAGE_MASK (~(PAGE_SIZE-1)) ... #define PAGE_ALIGN(addr) (((addr)+PAGE_SIZE-1)&PAGE_MASK) The "~" is performed on a 32-bit value, so everything in "and" with PAGE_MASK greater than 4GB will be truncated to the 32-bit boundary. Using the ALIGN() macro seems to be the right way, because it uses typeof(addr) for the mask. Also move the PAGE_ALIGN() definitions out of include/asm-*/page.h in include/linux/mm.h. See also lkml discussion: http://lkml.org/lkml/2008/6/11/237 [akpm@linux-foundation.org: fix drivers/media/video/uvc/uvc_queue.c] [akpm@linux-foundation.org: fix v850] [akpm@linux-foundation.org: fix powerpc] [akpm@linux-foundation.org: fix arm] [akpm@linux-foundation.org: fix mips] [akpm@linux-foundation.org: fix drivers/media/video/pvrusb2/pvrusb2-dvb.c] [akpm@linux-foundation.org: fix drivers/mtd/maps/uclinux.c] [akpm@linux-foundation.org: fix powerpc] Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-05-17 [PATCH] Fix a deadlock in the bttv driverMauro Carvalho Chehab
From: Arjan van de Ven <arjan@linux.intel.com> vidiocgmbuf() does this: mutex_lock(&fh->cap.vb_lock); retval = videobuf_mmap_setup(&fh->cap, gbuffers, gbufsize, V4L2_MEMORY_MMAP); and videobuf_mmap_setup() then just does mutex_lock(&q->vb_lock); ret = __videobuf_mmap_setup(q, bcount, bsize, memory); mutex_unlock(&q->vb_lock); which is an obvious double-take deadlock. This patch fixes this by having vidiocgmbuf() just call the __videobuf_mmap_setup function instead. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-05-02backport commit a6a3a17b7fdaf824e6d73e8e4a94c9d149302f74Mauro Carvalho Chehab
kernel-sync: Author: Harvey Harrison <harvey.harrison@gmail.com> Date: Mon Apr 28 16:50:03 2008 -0700 media: fix integer as NULL pointer warnings drivers/media/video/v4l2-common.c:719:16: warning: Using plain integer as NULL pointer drivers/media/video/au0828/au0828-dvb.c:122:19: warning: Using plain integer as NULL pointer drivers/media/video/ivtv/ivtv-yuv.c:1101:22: warning: Using plain integer as NULL pointer drivers/media/video/ivtv/ivtv-yuv.c:1102:23: warning: Using plain integer as NULL pointer drivers/media/video/pvrusb2/pvrusb2-audio.c:78:39: warning: Using plain integer as NULL pointer drivers/media/video/pvrusb2/pvrusb2-video-v4l.c:84:39: warning: Using plain integer as NULL pointer drivers/media/video/pvrusb2/pvrusb2-v4l2.c:1264:9: warning: Using plain integer as NULL pointer drivers/media/video/pvrusb2/pvrusb2-context.c:197:28: warning: Using plain integer as NULL pointer drivers/media/video/pvrusb2/pvrusb2-cx2584x-v4l.c:126:39: warning: Using plain integer as NULL pointer drivers/media/video/pvrusb2/pvrusb2-dvb.c:133:32: warning: Using plain integer as NULL pointer drivers/media/video/pvrusb2/pvrusb2-dvb.c:145:31: warning: Using plain integer as NULL pointer drivers/media/video/pvrusb2/pvrusb2-dvb.c:177:55: warning: Using plain integer as NULL pointer drivers/media/video/videobuf-core.c:100:9: warning: Using plain integer as NULL pointer Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-26videobuf-core: backport brandon's patchMauro Carvalho Chehab
From: Mauro Carvalho Chehab <mchehab@infradead.org> I and Brandon did similar patches. As Brandon patch where older, I've preserved his patch at -git. However, the patches weren't equal. kernel-sync: Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-13videobuf-dvb: allow its usage with videobuf-vmallocMauro Carvalho Chehab
From: Mauro Carvalho Chehab <mchehab@infradead.org> videobuf-dvb were still using a function that were videobuf-dma-sg dependent. This patch creates a generic handler for this function. This way, videobuf-dvb can now work with all videobuf implementations. Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-13videobuf: All videobuf clients need a spinlockMauro Carvalho Chehab
From: Mauro Carvalho Chehab <mchehab@infradead.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-13videobuf-vmalloc: stop streaming before unmapMauro Carvalho Chehab
From: Mauro Carvalho Chehab <mchehab@infradead.org> Before the patch, there were a risk of freeing and unmapping userspace memory, while there were pending requests. Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-13videbuf-vmalloc: Corrects mmap codeMauro Carvalho Chehab
From: Mauro Carvalho Chehab <mchehab@infradead.org> There were some bugs on videobuf-vmalloc. Basically, remap were called with a wrong parameter. Due to that, a later remap were needed, generating the need of some hacks on videobuf-vmalloc and videobuf-core. This patch fixes the remap and removes the hacks. TODO: - V4L2_MEMORY_USERPTR is not implemented yet. This method should be properly implemented, in order to work with a few userspace applications. - The driver also doesn't implement V4L2_MEMORY_OVERLAY. This method is used only by a few applications, and are becaming obsolete, due to the increment of cpu performance. So, most apps prefer to retrieve data to an internal buffer, doing some processing like de-interlacing. Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-13videobuf: revert changeset #7490:5b77f099a151Mauro Carvalho Chehab
From: Mauro Carvalho Chehab <mchehab@infradead.org> This changeset were supposed to optimize mmap() support on vmalloc. However, it just broke mmap() on real devices. Revert the changeset to make mmap() to work again. Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-08media/video/ replace remaining __FUNCTION__ occurrencesMichael Krufky
From: Harvey Harrison <harvey.harrison@gmail.com> __FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
2008-04-02videobuf: Avoid deadlock with QBUF and bring up to spec for empty queueBrandon Philips
Add a waitqueue to wait on when there are no buffers in the buffer queue. DQBUF waits on this queue without holding vb_lock to allow a QBUF to happen. Once a buffer has been queued we recheck that the queue is still streaming and wait on the new buffer's waitqueue while holding the vb_lock. The driver should come along in a timely manner and put the buffer into its next state finishing the DQBUF. By implementing this waitqueue it also brings the videobuf DQBUF up to spec and it now blocks on O_NONBLOCK even when no buffers have been queued via QBUF: "By default VIDIOC_DQBUF blocks when no buffer is in the outgoing queue." - V4L2 spec CC: Trent Piepho <xyzzy@speakeasy.org> CC: Carl Karsten <carl@personnelware.com> CC: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Brandon Philips <bphilips@suse.de> --- linux/drivers/media/video/videobuf-core.c | 96 +++++++++++++++++++++++------- linux/include/media/videobuf-core.h | 2 2 files changed, 78 insertions(+), 20 deletions(-)
2008-04-02videobuf-vmalloc.c: Fix hack of postponing mmap on remap failureBrandon Philips
In videobuf-vmalloc.c remap_vmalloc_range is failing when applications are trying to mmap buffers immediately after reqbuf. It fails because the vmalloc area isn't setup until the first QBUF when drivers call iolock. This patch introduces mmap_setup to the qtype_ops and it is called in __videobuf_mmap_setup if the buffer type is mmap. In the case of vmalloc buffers this calls iolock, and sets the state to idle. I don't think this is needed for dma-sg buffers and it defaults to a no-op for everything but vmalloc. Signed-off-by: Brandon Philips <bphilips@suse.de> --- linux/drivers/media/video/videobuf-core.c | 29 +++++++----------- linux/drivers/media/video/videobuf-vmalloc.c | 43 +++++++++++++-------------- linux/include/media/videobuf-core.h | 3 + 3 files changed, 35 insertions(+), 40 deletions(-)
2008-04-02videobuf: Simplify videobuf_waiton logic and possibly avoid missed wakeupBrandon Philips
Possible missed wakeup- use kernel helpers for wait queues http://www.mail-archive.com/linux-usb-devel@lists.sourceforge.net/msg27983.html Signed-off-by: Brandon Philips <bphilips@suse.de> --- linux/drivers/media/video/videobuf-core.c | 37 ++++++++++++------------------ 1 file changed, 15 insertions(+), 22 deletions(-)
2008-04-02videobuf: Wakeup queues after changing the state to ERRORBrandon Philips
The waitqueues must be woken up every time state changes. Signed-off-by: Brandon Philips <bphilips@suse.de> --- linux/drivers/media/video/videobuf-core.c | 1 + 1 file changed, 1 insertion(+)
2008-03-14 cleanup variable initializationMauro Carvalho Chehab
From: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> flags used for spinlocks don't need to be initialized, except where the compiler has no way to see, that the spin_unlock_irqrestore is only called if the spin_lock_irqsave has been called before. Local variable initialization doesn't have to be protected. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> Reviewed-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-03-14 Improve compile-time type-checking in videobufMauro Carvalho Chehab
From: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> Make the dev member of the struct videobuf_queue of type "struct device *" to avoid future problems. Also change the prototype of the videobuf_queue_core_init() function. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-02-26v4l: Deadlock in videobuf-core for DQBUF waiting on QBUFBrandon Philips
Avoid a deadlock where DQBUF is holding the vb_lock while waiting on a QBUF which also needs the vb_lock. Reported by Hans Verkuil <hverkuil@xs4all.nl>. From: Brandon Philips <brandon@ifup.org> Signed-off-by: Brandon Philips <bphilips@suse.de>
2008-01-31Renames videobuf lock to vb_lockMauro Carvalho Chehab
From: Mauro Carvalho Chehab <mchehab@infradead.org> This helps to identify where vb_lock is being used, and find missusages of the locks. Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-01-13Fix a regresion left by changeset 7e65d6e8f6dfMauro Carvalho Chehab
From: Mauro Carvalho Chehab <mchehab@infradead.org> Changeset 7e65d6e8f6df removed a very bad hack on mmap(). However, the fixes weren't considering usermap and overlay memory models. This were breaking direct reading from /dev/video?, used mostly by mpeg aware drivers. Thanks to Steven Toth <stoth@linuxtv.org> for reporting the issue and bissecting it. CC: Steven Toth <stoth@linuxtv.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-01-10Replace a very dirty hack on videobuf for a clean wait_eventMauro Carvalho Chehab
From: Mauro Carvalho Chehab <mchehab@infradead.org> In order to videobuf_iolock to work, mmap_mapper should be called first. Otherwise, an OOPS is generated. On some cases, .mmap file handler used to took some time to be called. On those situations, mmap_mmapper() were called after iolock. This patch properly waits for mmap_mapper to be called, otherwise generating an error. Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-12-12__videobuf_read_start is staticMauro Carvalho Chehab
From: Mauro Carvalho Chehab <mchehab@infradead.org> Thanks to Jean Delvare <khali@linux-fr.org> for pointing this. Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-12-12 buf-core.c locking fixesMauro Carvalho Chehab
From: Adrian Bunk <bunk@stusta.de> After commit 19fb1457990b6b7e15586ec7331541a184233acc the callers in videobuf-core.c that already hold the lock must call __videobuf_read_start() instead of videobuf_read_start(). Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-12-10CodingStyle fixesMauro Carvalho Chehab
From: Mauro Carvalho Chehab <mchehab@infradead.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-11-16Re-adds lock safe videobuf_read_startMauro Carvalho Chehab
From: Mauro Carvalho Chehab <mchehab@infradead.org> videobuf_dvb needs videobuf_read_start. The EXPORT_SYMBOL_GPL() were removed by a previous patch. However, videobuf_dvb needs this. This patch re-adds videobuf_read_start, doing the proper lock. Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-11-15merge: http://ifup.org/hg/v4l-dvbMauro Carvalho Chehab
From: Mauro Carvalho Chehab <mchehab@infradead.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-11-13V4L: videobuf-core locking fixes and commentsBrandon Philips
- Add comments to functions that require that caller hold q->lock - Add __videobuf_mmap_free that doesn't hold q->lock for use within videobuf - Add locking to videobuf_mmap_free - Fix linux/drivers/media/common/saa7146_video.c which was holding lock around videobuf_read_stop - Add locking to functions that operate on a queue - Add videobuf_stop to take care of stopping in both the read and stream case TODO: bttv still has an unsafe call to videobuf_queue_is_busy Signed-off-by: Brandon Philips <bphilips@suse.de>
2007-11-06V4L: videobuf: don't chew up namespace STATE_.*, convert to VIDEOBUF_Brandon Philips
s/STATE_NEEDS_INIT/VIDEOBUF_NEEDS_INIT/g s/STATE_PREPARED/VIDEOBUF_PREPARED/g s/STATE_QUEUED/VIDEOBUF_QUEUED/g s/STATE_ACTIVE/VIDEOBUF_ACTIVE/g s/STATE_DONE/VIDEOBUF_DONE/g s/STATE_ERROR/VIDEOBUF_ERROR/g s/STATE_IDLE/VIDEOBUF_IDLE/g Signed-off-by: Brandon Philips <bphilips@suse.de>
2007-10-17backport changeset 13bcd5d0e21e3ca726965371ada8ff6c64af288fMauro Carvalho Chehab
From: Mauro Carvalho Chehab <mchehab@infradead.org> Original description: Author: Al Viro <viro@ftp.linux.org.uk> Date: Sat Oct 13 08:25:24 2007 +0100 v4l: copy_to_user() is not a good method name Breaks on any target that has copy_to_user() defined as a non-trivial macro. kernel-sync: Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-10-13 fix videobuf_cgmbuf exportMauro Carvalho Chehab
From: Pekka Enberg <penberg@cs.helsinki.fi> As videobuf_cgmbuf is defined only if CONFIG_VIDEO_V4L1_COMPAT is enabled, move the EXPORT_SYMBOL_GPL declaration inside the #ifdef block. Fixes compilation for x86_64 defconfig. Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> CC: Ingo Molnar <mingo@elte.hu> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-10-11 git-dvb: rename videobuf_qtype_ops.copy_to_user()Mauro Carvalho Chehab
From: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-10-10Change list_for_each+list_entry to list_for_each_entryTrent Piepho
From: Trent Piepho <xyzzy@speakeasy.org> The rest of V4L files. There is one list_for_each+list_entry in cpia_pp.c that wasn't changed because it expects the loop iterator to remain NULL if the list is empty. A bug in vivi is fixed; the 'safe' version needs to be used because the loop deletes the list entries. Simplify a second loop in vivi and get rid if an un-used variable in that loop. Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
2007-10-05 V4L: videobuf-core.c avoid NULL dereferences in videobuf-coreMauro Carvalho Chehab
From: Brandon Philips <bphilips@suse.de> The return value of videobuf_alloc() is unchecked but this function will return NULL on an error. Check for NULL and make videobuf_reqbufs() return the number of successfully allocated buffers. Also, fix saa7146_video.c and bttv-driver.c to use this returned buffer count. Tested against the vivi driver. Not tested against saa7146 or bt8xx devices. Signed-off-by: Brandon Philips <bphilips@suse.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-10-08videobuf_core init always require callback implementationMauro Carvalho Chehab
From: Mauro Carvalho Chehab <mchehab@infradead.org> In the past, videobuf_queue_init were used to initialize PCI DMA videobuffers. This patch renames it, to avoid confusion with the previous kernel API, doing: s/videobuf_queue_init/void videobuf_queue_core_init/ Also, the operations is now part of the function parameter. The function will also add a test if this is defined, otherwise producing BUG. Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-10-08Fix: avoid oops on some SMP machinesMauro Carvalho Chehab
From: Mauro Carvalho Chehab <mchehab@infradead.org> This workaround fix a bug that happens on some SMP machines. On those machines, videobuf_iolock is called too soon, before file .mmap handler. This patch calls the scheduler before iolocking, allowing it to properly call the pending mmap. Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-10-02Buf: fix typo that caused data loss when readng streams from deviceMaxim Levitsky
If videobuf_read_stream reads two or more buffers it was overwriting the first one Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org> http://thread.gmane.org/gmane.comp.video.video4linux/34978/focus=34981 Reviewed-by: Ricardo Cerqueira <v4l@cerqueira.org>
2007-09-27V4L: videobuf-core.c lock before streaming checkbphilips@suse.de
The reading/streaming fields are used for mutual exclusion of the queue and should be protected by the queue lock. Signed-off-by: Brandon Philips <bphilips@suse.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org> http://thread.gmane.org/gmane.comp.video.video4linux/34978/focus=34981 Reviewed-by: Ricardo Cerqueira <v4l@cerqueira.org>
2007-09-27V4L: Fix a lock inversion in generic videobuf codeMaxim Levitsky
videobuf_qbuf takes q->lock, and then calls q->ops->buf_prepare which by design in all drivers calls videobuf_iolock which calls videobuf_dma_init_user and this takes current->mm->mmap_sem on the other hand if user calls mumap from other thread, sys_munmap takes current->mm->mmap_sem and videobuf_vm_close takes q->lock Since this can occur only for V4L2_MEMORY_MMAP buffers, take current->mm->mmap_sem in qbuf, before q->lock, and don't take current->mm->mmap_sem videobuf_dma_init_user for those buffers Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org> http://thread.gmane.org/gmane.comp.video.video4linux/34978/focus=34981 Reviewed-by: Ricardo Cerqueira <v4l@cerqueira.org>
2007-09-27videobuf cleanup: mmap check is common to all videobuf. Make it at coreMauro Carvalho Chehab
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org> http://thread.gmane.org/gmane.comp.video.video4linux/34978/focus=34981 Reviewed-by: Ricardo Cerqueira <v4l@cerqueira.org>
2007-09-25Prevent for calling mmap_free without an allocated bufferMauro Carvalho Chehab
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org> http://thread.gmane.org/gmane.comp.video.video4linux/34978/focus=34981 Reviewed-by: Ricardo Cerqueira <v4l@cerqueira.org>
2007-08-23Replace video-buf to a more generic approachMauro Carvalho Chehab
video-buf currently does two different tasks: - Manages video buffers with a common code that allows implementing all the V4L2 different modes of buffering; - Controls memory allocations While the first task is generic, the second were written to support PCI DMA Scatter/Gather needs. The original approach can't even work for those video capture hardware that don't support scatter/gather. I did one approach to make it more generic. While the approach worked fine for vivi driver, it were not generic enough to handle USB needs. This patch creates two different modules, one containing the generic video buffer handling (videobuf-core) and another with PCI DMA S/G. After this patch, it would be simpler to write an USB video-buf and a non-SG DMA module. Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org> http://thread.gmane.org/gmane.comp.video.video4linux/34978/focus=34981 Reviewed-by: Ricardo Cerqueira <v4l@cerqueira.org>