V4L/DVB (5891): zr36067: Turn off raw capture properly

When raw capture was turned off, the current capturing frame (v4l_grab_frame)
wasn't reset to NO_GRAB_ACTIVE.  If capture was turned back on, the driver
would think this frame was currently being captured, and wait for it to
complete before starting a new frame.  The hardware on the other hand would
not be actively capturing a frame.  The result was the driver would wait
forever for v4l_grab_frame to be captured.

Some calls to zr36057_set_memgrab(0) were missing spin-locks, which have been
added.

Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Acked-by: Ronald S. Bultje <rbultje@ronald.bitfreak.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

2 files changed, 26 insertions, 6 deletions

diff --git a/drivers/media/video/zoran_device.c b/drivers/media/video/zoran_device.c
index d9640ec4b9b..ba2f4ed2948 100644
--- a/drivers/media/video/zoran_device.c
+++ b/drivers/media/video/zoran_device.c
@@ -620,11 +620,17 @@ zr36057_set_memgrab (struct zoran *zr,
 		     int           mode)
 {
 	if (mode) {
-		if (btread(ZR36057_VSSFGR) &
-		    (ZR36057_VSSFGR_SnapShot | ZR36057_VSSFGR_FrameGrab))
+		/* We only check SnapShot and not FrameGrab here.  SnapShot==1
+		 * means a capture is already in progress, but FrameGrab==1
+		 * doesn't necessary mean that.  It's more correct to say a 1
+		 * to 0 transition indicates a capture completed.  If a
+		 * capture is pending when capturing is tuned off, FrameGrab
+		 * will be stuck at 1 until capturing is turned back on.
+		 */
+		if (btread(ZR36057_VSSFGR) & ZR36057_VSSFGR_SnapShot)
 			dprintk(1,
 				KERN_WARNING
-				"%s: zr36057_set_memgrab(1) with SnapShot or FrameGrab on!?\n",
+				"%s: zr36057_set_memgrab(1) with SnapShot on!?\n",
 				ZR_DEVNAME(zr));
 
 		/* switch on VSync interrupts */
@@ -641,11 +647,12 @@ zr36057_set_memgrab (struct zoran *zr,
 
 		zr->v4l_memgrab_active = 1;
 	} else {
-		zr->v4l_memgrab_active = 0;
-
 		/* switch off VSync interrupts */
 		btand(~zr->card.vsync_int, ZR36057_ICR);	// SW
 
+		zr->v4l_memgrab_active = 0;
+		zr->v4l_grab_frame = NO_GRAB_ACTIVE;
+
 		/* reenable grabbing to screen if it was running */
 		if (zr->v4l_overlay_active) {
 			zr36057_overlay(zr, 1);
diff --git a/drivers/media/video/zoran_driver.c b/drivers/media/video/zoran_driver.c
index ec9ae6c61bd..72a037b75d6 100644
--- a/drivers/media/video/zoran_driver.c
+++ b/drivers/media/video/zoran_driver.c
@@ -1188,10 +1188,14 @@ zoran_close_end_session (struct file *file)
 
 	/* v4l capture */
 	if (fh->v4l_buffers.active != ZORAN_FREE) {
+		long flags;
+
+		spin_lock_irqsave(&zr->spinlock, flags);
 		zr36057_set_memgrab(zr, 0);
 		zr->v4l_buffers.allocated = 0;
 		zr->v4l_buffers.active = fh->v4l_buffers.active =
 		    ZORAN_FREE;
+		spin_unlock_irqrestore(&zr->spinlock, flags);
 	}
 
 	/* v4l buffers */
@@ -3456,8 +3460,13 @@ zoran_do_ioctl (struct inode *inode,
 				goto strmoff_unlock_and_return;
 
 			/* unload capture */
-			if (zr->v4l_memgrab_active)
+			if (zr->v4l_memgrab_active) {
+				long flags;
+
+				spin_lock_irqsave(&zr->spinlock, flags);
 				zr36057_set_memgrab(zr, 0);
+				spin_unlock_irqrestore(&zr->spinlock, flags);
+			}
 
 			for (i = 0; i < fh->v4l_buffers.num_buffers; i++)
 				zr->v4l_buffers.buffer[i].state =
@@ -4392,11 +4401,15 @@ zoran_vm_close (struct vm_area_struct *vma)
 				mutex_lock(&zr->resource_lock);
 
 				if (fh->v4l_buffers.active != ZORAN_FREE) {
+					long flags;
+
+					spin_lock_irqsave(&zr->spinlock, flags);
 					zr36057_set_memgrab(zr, 0);
 					zr->v4l_buffers.allocated = 0;
 					zr->v4l_buffers.active =
 					    fh->v4l_buffers.active =
 					    ZORAN_FREE;
+					spin_unlock_irqrestore(&zr->spinlock, flags);
 				}
 				//v4l_fbuffer_free(file);
 				fh->v4l_buffers.allocated = 0;