davinci_vpfe: extra safety checks

drivers/media/video/davinci_vpfe.c

@@ -264,19 +264,19 @@ buffer_setup(struct videobuf_queue *q, unsigned int *count, unsigned int *size)
 
 	for (i = VPFE_DEFNUM_FBUFS; i < *count; i++)
 	{
-		u32 size = PAGE_SIZE << VPFE_MAX_FBUF_ORDER;
+		u32 bufsize = PAGE_SIZE << VPFE_MAX_FBUF_ORDER;
 		void *mem = (void *)__get_free_pages(GFP_KERNEL |GFP_DMA,
 											 VPFE_MAX_FBUF_ORDER);
 		if (mem)
 		{
 			unsigned long adr = (unsigned long)mem;
-			while (size > 0)
+			while (bufsize > 0)
 			{
 				/* make sure the frame buffers are never
 				   swapped out of memory */
 				SetPageReserved(virt_to_page(adr));
 				adr += PAGE_SIZE;
-				size -= PAGE_SIZE;
+				bufsize -= PAGE_SIZE;
 			}
 			vpfe->fbuffers[i] = mem;
 		}
@@ -301,7 +301,7 @@ static void buffer_queue(struct videobuf_queue *q, struct videobuf_buffer *vb)
 
 static void buffer_release(struct videobuf_queue *q, struct videobuf_buffer *vb)
 {
-	/* free the buffer if it is not one of the 3 allocated at initializaiton time */
+	/* free the buffer if it is not one of the 3 allocated at initialization time */
 	if (vb->i < vpfe_device.numbuffers
 		&& vb->i >= VPFE_DEFNUM_FBUFS
 		&& vpfe_device.fbuffers[vb->i])
@@ -969,12 +969,17 @@ static int vpfe_doioctl(struct inode *inode, struct file *file,
 				ret = -EINVAL;
 				break;
 			}
+
+			flush_scheduled_work();
+
 			/* disable CCDC */
 			down_interruptible(&vpfe->lock);
 			ccdc_enable(FALSE);
+			vpfe->io_usrs = 0;
 			vpfe->started = FALSE;
 			up(&vpfe->lock);
 			ret = videobuf_streamoff(&vpfe->bufqueue);
+			debug_print(KERN_INFO "stopped video streaming.\n");
 			break;
 		}
 	case VPFE_CMD_CONFIG_CCDC:
@@ -1124,8 +1129,10 @@ static int vpfe_release(struct inode *inode, struct file *filep)
 	vpfe_fh *fh = filep->private_data;
 	vpfe_obj *vpfe = fh->dev;
 
+	flush_scheduled_work();
+
 	down_interruptible(&vpfe->lock);
-	if (fh->io_allowed)
+	if (fh->io_allowed && vpfe->started && vpfe->io_usrs != 0)
 	{
 		vpfe->io_usrs = 0;
 		ccdc_enable(FALSE);