[media] arv: fix sleep_on race

interruptible_sleep_on is racy and going away. In the arv driver that
race has probably never caused problems since it would require a whole
video frame to be captured before the read function has a chance to
go to sleep, but using wait_event_interruptible lets us kill off the
old interface. In order to do this, we have to slightly adapt the
meaning of the ar->start_capture field to distinguish between not having
started a frame and having completed it.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/drivers/media/platform/arv.c b/drivers/media/platform/arv.c
index e346d32d08ce..e9410e41ae0c 100644
--- a/drivers/media/platform/arv.c
+++ b/drivers/media/platform/arv.c
@@ -109,7 +109,7 @@ extern struct cpuinfo_m32r	boot_cpu_data;
 struct ar {
         struct v4l2_device v4l2_dev;
         struct video_device vdev;
-        unsigned int start_capture;     /* duaring capture in INT. mode. */
+        int start_capture;      /* duaring capture in INT. mode. */
 #if USE_INT
         unsigned char *line_buff;       /* DMA line buffer */
 #endif
@@ -307,11 +307,11 @@ static ssize_t ar_read(struct file *file, char *buf, size_t count, loff_t *ppos)
         /*
          * Okay, kick AR LSI to invoke an interrupt
          */
-        ar->start_capture = 0;
+        ar->start_capture = -1;
         ar_outl(arvcr1 | ARVCR1_HIEN, ARVCR1);
         local_irq_restore(flags);
         /* .... AR interrupts .... */
-        interruptible_sleep_on(&ar->wait);
+        wait_event_interruptible(ar->wait, ar->start_capture == 0);
         if (signal_pending(current)) {
                 printk(KERN_ERR "arv: interrupted while get frame data.\n");
                 ret = -EINTR;