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 d9640ec4b9b0..ba2f4ed29483 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 ec9ae6c61bd5..72a037b75d63 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;