summaryrefslogtreecommitdiff
path: root/drivers/media/usb/cpia2/cpia2_usb.c
AgeCommit message (Collapse)Author
2016-10-21[media] cpia2: don't break long linesMauro Carvalho Chehab
Due to the 80-cols restrictions, and latter due to checkpatch warnings, several strings were broken into multiple lines. This is not considered a good practice anymore, as it makes harder to grep for strings at the source code. As we're right now fixing other drivers due to KERN_CONT, we need to be able to identify what printk strings don't end with a "\n". It is a way easier to detect those if we don't break long lines. So, join those continuation lines. The patch was generated via the script below, and manually adjusted if needed. </script> use Text::Tabs; while (<>) { if ($next ne "") { $c=$_; if ($c =~ /^\s+\"(.*)/) { $c2=$1; $next =~ s/\"\n$//; $n = expand($next); $funpos = index($n, '('); $pos = index($c2, '",'); if ($funpos && $pos > 0) { $s1 = substr $c2, 0, $pos + 2; $s2 = ' ' x ($funpos + 1) . substr $c2, $pos + 2; $s2 =~ s/^\s+//; $s2 = ' ' x ($funpos + 1) . $s2 if ($s2 ne ""); print unexpand("$next$s1\n"); print unexpand("$s2\n") if ($s2 ne ""); } else { print "$next$c2\n"; } $next=""; next; } else { print $next; } $next=""; } else { if (m/\"$/) { if (!m/\\n\"$/) { $next=$_; next; } } } print $_; } </script> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-10-14[media] cpia2_usb: don't use stack for DMAMauro Carvalho Chehab
The USB control messages require DMA to work. We cannot pass a stack-allocated buffer, as it is not warranted that the stack would be into a DMA enabled area. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-08-24[media] media: usb: cpia2: cpia2_usb: don't print error when allocating urb ↵Wolfram Sang
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>
2015-11-17[media] media: fix waitqueue_active without memory barrier in cpia2 driverKosuke Tatsukawa
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>
2013-10-17[media] media: Change variable type to boolPeter Senna Tschudin
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>
2012-12-21[media] v4l: Convert drivers to use monotonic timestampsSakari Ailus
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>
2012-08-15[media] rename most media/video usb drivers to media/usbMauro Carvalho Chehab
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>