Commit Graph

9 Commits

Author SHA1 Message Date
Wolfram Sang fa460caf16 [media] media: usb: cpia2: cpia2_usb: don't print error when allocating urb fails
kmalloc will print enough information in case of failure.

Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-08-24 08:48:56 -03:00
Dan Carpenter 76880b4015 [media] usb/cpia2_core: clean up a min_t() cast
It makes sense to make the min_t() cast unsigned here since we don't
really want negative sizes.  Making it signed causes a static checker
warning in Smatch.  Smatch knows "fw->size - i" is positive but it
doesn't know that fw->size is less than INT_MAX so in theory casting it
to int might lead to a negative.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2016-02-19 08:10:32 -02:00
Kosuke Tatsukawa 5063452ecb [media] media: fix waitqueue_active without memory barrier in cpia2 driver
cpia2_usb_disconnect() seems to be missing a memory barrier which might
cause the waker to not notice the waiter and miss sending a wake_up as
in the following figure.

	cpia2_usb_disconnect			sync
------------------------------------------------------------------------
					mutex_unlock(&cam->v4l2_lock);
if (waitqueue_active(&cam->wq_stream))
/* The CPU might reorder the test for
   the waitqueue up here, before
   prior writes complete */
					/* wait_event_interruptible */
					 /* __wait_event_interruptible */
					  /* ___wait_event */
					  long __int = prepare_to_wait_event(
					    &wq, &__wait, state);
					  if (!cam->streaming ||
					    frame->status == FRAME_READY)
cam->curbuff->status = FRAME_READY;
cam->curbuff->length = 0;
					  schedule()
------------------------------------------------------------------------

The attached patch removes the call to waitqueue_active() leaving just
wake_up() behind.  This fixes the problem because the call to
spin_lock_irqsave() in wake_up() will be an ACQUIRE operation.

I found this issue when I was looking through the linux source code
for places calling waitqueue_active() before wake_up*(), but without
preceding memory barriers, after sending a patch to fix a similar
issue in drivers/tty/n_tty.c  (Details about the original issue can be
found here: https://lkml.org/lkml/2015/9/28/849).

Signed-off-by: Kosuke Tatsukawa <tatsu@ab.jp.nec.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2015-11-17 14:55:06 -02:00
Ramakrishnan Muthukrishnan 95cd5d5ee6 [media] media: remove the setting of the flag V4L2_FL_USE_FH_PRIO
Since all the drivers that use `struct v4l2_fh' use the core
priority checking, the setting of the flag in the drivers can
be removed.

Signed-off-by: Ramakrishnan Muthukrishnan <ramakrmu@cisco.com>
Reviewed-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
2014-07-04 16:14:59 -03:00
Peter Senna Tschudin b5eee19617 [media] media: Change variable type to bool
The variable frame_ready is only assigned the values true and false.
Change its type to bool.
The simplified semantic patch that find this problem is as
follows (http://coccinelle.lip6.fr/):
@exists@
type T;
identifier b;
@@
- T
+ bool
  b = ...;
  ... when any
  b = \(true\|false\)

Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
2013-10-17 11:24:35 -03:00
Sakari Ailus 1b18e7a0be [media] v4l: Tell user space we're using monotonic timestamps
Set buffer timestamp flags for videobuf, videobuf2 and drivers that use
neither.

Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-12-21 11:20:51 -02:00
Sakari Ailus 8e6057b510 [media] v4l: Convert drivers to use monotonic timestamps
Convert drivers using wall clock time (CLOCK_REALTIME) to timestamp from the
monotonic timer (CLOCK_MONOTONIC).

Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-12-21 10:56:43 -02:00
Hans Verkuil d88aab53bd [media] v4l2: make vidioc_s_jpegcomp const
Write-only ioctls should have a const argument in the ioctl op.
Do this conversion for vidioc_s_jpegcomp.
Adding const for write-only ioctls was decided during the 2012 Media Workshop.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-09-26 10:43:04 -03:00
Mauro Carvalho Chehab 0c0d06cac6 [media] rename most media/video usb drivers to media/usb
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>
2012-08-15 16:25:07 -03:00