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path: root/drivers/media/video/pvrusb2/pvrusb2-context.c
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2012-08-15[media] rename most media/video usb drivers to media/usbMauro Carvalho Chehab1-431/+0
Rename all USB drivers with their own directory under drivers/media/video into drivers/media/usb and update the building system. Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2008-07-20V4L/DVB (7936): pvrusb2: Remove svn Id keyword from all sourcesMike Isely1-1/+0
Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-29media: fix integer as NULL pointer warningsHarvey Harrison1-1/+1
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: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-24V4L/DVB (7719): pvrusb2: Implement input selection enforcementMike Isely1-0/+69
In the pvrusb2 driver, different interfaces (e.g. V4L, DVB) have Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7714): pvrusb2: Fix hang on module removalMike Isely1-1/+18
The pvrusb2 driver was getting had by this scenario: 1. Task A calls kthread_stop() for task B. 2. Before exiting, then Task B calls kthread_stop() for task C. The problem is, kthread_stop() wants to allocate an internal resource to itself (i.e. acquire a lock), which won't be released until kthread_stop() returns. But kthread_stop() won't return until task B is dead. But task B won't die until it finishes its call to kthread_stop() for task C, and that will block waiting on the resource already allocated inside task A. Deadlock. With the pvrusb2 driver, task A is the caller to pvr_exit(), task B is the control thread run inside of pvrusb2-context.c, and task C is any worker thread run inside of pvrusb2-hdw.c. This problem got introduced by the previous threading setup change, which was itself an attempt to fix a module tear-down race (which it actually did fix). The lesson here is that a task being waited on as part of a kthread_stop() simply cannot be allow to also issue a kthread_stop() - or we make sure not to issue the enclosing kthread_stop() until we know that the inner kthread_stop() has completed first. The solution for the pvrusb2 driver is some hackish code which changes the main control thread tear down into a two step process. This then makes it possible to delay issuing the kthread_stop() on the control thread until after we know that everything has been torn down first. (And yes, we really need that kthread_stop() because it's the only way to safely guarantee that a module-referencing kernel thread has safely returned back out of the module before we finally remove the module.) Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7711): pvrusb2: Fix race on module unloadMike Isely1-49/+155
The pvrusb2 driver - for basically forever - was not enforcing a proper module tear-down. Kernel threads are used inside the driver and all must be gone before the module can be safely removed. This changeset reimplements a chunk of pvrusb2-context.c to enforce this correctly. Unfortunately this is not a simple fix. The new implementation also cuts back on kernel thread usage; instead of there being 1 control thread per instance now it's just 1 control thread shared by all instances. (By dropping to a single thread then the module exit function can block on its shutdown and the thread itself can monitor and cleanly shut down all of the other instances first.) Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7321): pvrusb2: Rework context handling and initializationMike Isely1-43/+70
This change significantly rearranges pvr2_context level initialization and operation: 1. A new kernel thread is set up for management of the context. 2. Destruction of the pvr2_context instance is moved into the kernel thread. No other context is able to remove the instance; doing this simplifies lock handling. 3. The callback into pvrusb2-main, which is used to trigger initialization of each interface, is now issued from this kernel thread. Previously it had been indirectly issued out of the work queue thread in pvr2_hdw, which led to deadlock issues if the interface needed to change a control setting (which in turn requires dispatch of another work queue entry). 4. Callbacks into the interfaces (via the pvr2_channel structure) are now issued strictly from this thread. The net result of this is that such callback functions can now also safely operate driver controls without deadlocking the work queue. (At the moment this is not actually a problem, but I'm anticipating issues with this in the future). 5. There is no longer any need for anyone to enter / exit the pvr2_context structure. Implementation of the kernel thread here allows this all to be internal now, simplifying other logic. 6. A very very longstanding issue involving a mutex deadlock between the pvrusb2 driver and v4l should now be solved. The deadlock involved the pvr2_context mutex and a globals-protecting mutex in v4l. During initialization the driver would take the pvr2_context mutex first then the v4l2 interface would register with v4l and implicitly take the v4l mutex. Later when v4l would call back into the driver, the two mutexes could possibly be taken in the opposite order, a situation that can lead to deadlock. In practice this really wasn't an issue unless a v4l app tried to start VERY early after the driver appeared. However it still needed to be solved, and with the use of the kernel thread relieving need for pvr2_context mutex, the problem should be finally solved. Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7319): pvrusb2: Close potential race condition during initializationMike Isely1-4/+3
There is a callback that is issued to into pvr2_context from pvr2_hdw after initialization is done. There was a probability that this callback could get missed. Fixed. Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7306): pvrusb2: Fix oops possible when claiming a NULL streamMike Isely1-1/+1
Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-19drivers: Remove unnecessary inclusions of asm/semaphore.hMatthew Wilcox1-1/+0
None of these files use any of the functionality promised by asm/semaphore.h. It's possible that they rely on it dragging in some unrelated header file, but I can't build all these files, so we'll have fix any build failures as they come up. Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2008-01-26V4L/DVB (6691): pvrusb2: Rework pipeline state controlMike Isely1-38/+17
This is a new implementation for video pipeline control within the pvrusb2 driver. Actual start/stop of the pipeline is moved to the driver's kernel thread. Pipeline stages are controlled autonomously based on surrounding pipeline or application control state. Kernel thread management is also cleaned up and moved into the internal control structure of the driver, solving a set up / tear down race along the way. Better failure recovery is implemented with this new control strategy. Also with this change comes better control of the cx23416 encoder, building on additional information learned about the peculiarities of controlling this part (this information was the original trigger for this rework). With this change, overall encoder stability should be considerably improved. Yes, this is a large change for this driver, but due to the nature of the feature being worked on, the changes are fairly pervasive and would be difficult to break into smaller pieces with any semblence of step-wise stability. Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-10-10V4L/DVB (6205): pvrusb2: Fix oops in error leg cleanupMike Isely1-2/+4
Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-02-21V4L/DVB (5091): Pvrusb2: Use kzalloc in place of kmalloc/memset pairsMike Isely1-2/+1
Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-02-21V4L/DVB (5052): Pvrusb2: Remove stream claiming hack from /dev/radioMike Isely1-11/+0
Trying to temporarily check that the stream is not claimed during open of the radio device is at best a race condition. What's to stop another app from claiming the stream anyway the instant after the check is done? The implementation for this was dicey anyway. So it's removed. The only "price" for this is that if /dev/radioX is opened while streaming video, then the video stream is just going to switch to radio mode anyway. If a user does this, he gets what he expects... Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-02-21V4L/DVB (5038): Pvrusb2: Implement stream claim checking functionPantelis Koukousoulas1-0/+11
Add (and expose) a new function, pvr2_channel_check_stream_no_lock(), in pvrusb2-context.c. This is hopefully the last V4L2 interface related patch to change anything outside pvrusb2-v4l2.c. We need this to implement the open() for the radio device. The reason is that within the *enter_context() section of open() we need to ensure nobody is streaming and if we cannot, we should cleanup after ourselves and return -EBUSY. We cannot just use claim_stream() because: 1) That would cause a deadlock trying to re-acquire the context lock 2) We only need to ensure that nobody is streaming. We don't need to actually acquire the stream. Again, this is a kinda ugly patch. Feel free to improve. Signed-off-by: Pantelis Koukousoulas <pakt223@freemail.gr> Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2006-11-22WorkStruct: make allyesconfigDavid Howells1-4/+9
Fix up for make allyesconfig. Signed-Off-By: David Howells <dhowells@redhat.com>
2006-06-30V4L/DVB (4288): Clean out a zillion sparse warnings in pvrusb2Mike Isely1-7/+7
Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2006-06-27V4L/DVB (4228a): pvrusb2 to kernel 2.6.18Mike Isely1-0/+230
Implement V4L2 driver for the Hauppauge PVR USB2 TV tuner. The Hauppauge PVR USB2 is a USB connected TV tuner with an embedded cx23416 hardware MPEG2 encoder. There are two major variants of this device; this driver handles both. Any V4L2 application which understands MPEG2 video stream data should be able to work with this device. Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>