2 files changed, 98 insertions, 19 deletions

diff --git a/drivers/media/usb/tm6000/tm6000-video.c b/drivers/media/usb/tm6000/tm6000-video.c
index f656fd7a39a2..82968017a253 100644
--- a/drivers/media/usb/tm6000/tm6000-video.c
+++ b/drivers/media/usb/tm6000/tm6000-video.c
@@ -49,12 +49,15 @@
 #define TM6000_MIN_BUF 4
 #define TM6000_DEF_BUF 8
 
+#define TM6000_NUM_URB_BUF 8
+
 #define TM6000_MAX_ISO_PACKETS	46	/* Max number of ISO packets */
 
 /* Declare static vars that will be used as parameters */
 static unsigned int vid_limit = 16;	/* Video memory limit, in Mb */
 static int video_nr = -1;		/* /dev/videoN, -1 for autodetect */
 static int radio_nr = -1;		/* /dev/radioN, -1 for autodetect */
+static int keep_urb;			/* keep urb buffers allocated */
 
 /* Debug level */
 int tm6000_debug;
@@ -538,6 +541,71 @@ static void tm6000_irq_callback(struct urb *urb)
 }
 
 /*
+ * Allocate URB buffers
+ */
+static int tm6000_alloc_urb_buffers(struct tm6000_core *dev)
+{
+	int num_bufs = TM6000_NUM_URB_BUF;
+	int i;
+
+	if (dev->urb_buffer != NULL)
+		return 0;
+
+	dev->urb_buffer = kmalloc(sizeof(void *)*num_bufs, GFP_KERNEL);
+	if (!dev->urb_buffer) {
+		tm6000_err("cannot allocate memory for urb buffers\n");
+		return -ENOMEM;
+	}
+
+	dev->urb_dma = kmalloc(sizeof(dma_addr_t *)*num_bufs, GFP_KERNEL);
+	if (!dev->urb_dma) {
+		tm6000_err("cannot allocate memory for urb dma pointers\n");
+		return -ENOMEM;
+	}
+
+	for (i = 0; i < num_bufs; i++) {
+		dev->urb_buffer[i] = usb_alloc_coherent(
+					dev->udev, dev->urb_size,
+					GFP_KERNEL, &dev->urb_dma[i]);
+		if (!dev->urb_buffer[i]) {
+			tm6000_err("unable to allocate %i bytes for transfer buffer %i\n",
+				    dev->urb_size, i);
+			return -ENOMEM;
+		}
+		memset(dev->urb_buffer[i], 0, dev->urb_size);
+	}
+
+	return 0;
+}
+
+/*
+ * Free URB buffers
+ */
+static int tm6000_free_urb_buffers(struct tm6000_core *dev)
+{
+	int i;
+
+	if (dev->urb_buffer == NULL)
+		return 0;
+
+	for (i = 0; i < TM6000_NUM_URB_BUF; i++) {
+		if (dev->urb_buffer[i]) {
+			usb_free_coherent(dev->udev,
+					dev->urb_size,
+					dev->urb_buffer[i],
+					dev->urb_dma[i]);
+			dev->urb_buffer[i] = NULL;
+		}
+	}
+	kfree(dev->urb_buffer);
+	kfree(dev->urb_dma);
+	dev->urb_buffer = NULL;
+	dev->urb_dma = NULL;
+
+	return 0;
+}
+
+/*
  * Stop and Deallocate URBs
  */
 static void tm6000_uninit_isoc(struct tm6000_core *dev)
@@ -551,18 +619,15 @@ static void tm6000_uninit_isoc(struct tm6000_core *dev)
 		if (urb) {
 			usb_kill_urb(urb);
 			usb_unlink_urb(urb);
-			if (dev->isoc_ctl.transfer_buffer[i]) {
-				usb_free_coherent(dev->udev,
-						urb->transfer_buffer_length,
-						dev->isoc_ctl.transfer_buffer[i],
-						urb->transfer_dma);
-			}
 			usb_free_urb(urb);
 			dev->isoc_ctl.urb[i] = NULL;
 		}
 		dev->isoc_ctl.transfer_buffer[i] = NULL;
 	}
 
+	if (!keep_urb)
+		tm6000_free_urb_buffers(dev);
+
 	kfree(dev->isoc_ctl.urb);
 	kfree(dev->isoc_ctl.transfer_buffer);
 
@@ -572,12 +637,13 @@ static void tm6000_uninit_isoc(struct tm6000_core *dev)
 }
 
 /*
- * Allocate URBs and start IRQ
+ * Assign URBs and start IRQ
  */
 static int tm6000_prepare_isoc(struct tm6000_core *dev)
 {
 	struct tm6000_dmaqueue *dma_q = &dev->vidq;
-	int i, j, sb_size, pipe, size, max_packets, num_bufs = 8;
+	int i, j, sb_size, pipe, size, max_packets;
+	int num_bufs = TM6000_NUM_URB_BUF;
 	struct urb *urb;
 
 	/* De-allocates all pending stuff */
@@ -605,6 +671,7 @@ static int tm6000_prepare_isoc(struct tm6000_core *dev)
 
 	max_packets = TM6000_MAX_ISO_PACKETS;
 	sb_size = max_packets * size;
+	dev->urb_size = sb_size;
 
 	dev->isoc_ctl.num_bufs = num_bufs;
 
@@ -627,6 +694,17 @@ static int tm6000_prepare_isoc(struct tm6000_core *dev)
 		    max_packets, num_bufs, sb_size,
 		    dev->isoc_in.maxsize, size);
 
+
+	if (!dev->urb_buffer && tm6000_alloc_urb_buffers(dev) < 0) {
+		tm6000_err("cannot allocate memory for urb buffers\n");
+
+		/* call free, as some buffers might have been allocated */
+		tm6000_free_urb_buffers(dev);
+		kfree(dev->isoc_ctl.urb);
+		kfree(dev->isoc_ctl.transfer_buffer);
+		return -ENOMEM;
+	}
+
 	/* allocate urbs and transfer buffers */
 	for (i = 0; i < dev->isoc_ctl.num_bufs; i++) {
 		urb = usb_alloc_urb(max_packets, GFP_KERNEL);
@@ -638,17 +716,8 @@ static int tm6000_prepare_isoc(struct tm6000_core *dev)
 		}
 		dev->isoc_ctl.urb[i] = urb;
 
-		dev->isoc_ctl.transfer_buffer[i] = usb_alloc_coherent(dev->udev,
-			sb_size, GFP_KERNEL, &urb->transfer_dma);
-		if (!dev->isoc_ctl.transfer_buffer[i]) {
-			tm6000_err("unable to allocate %i bytes for transfer"
-					" buffer %i%s\n",
-					sb_size, i,
-					in_interrupt() ? " while in int" : "");
-			tm6000_uninit_isoc(dev);
-			return -ENOMEM;
-		}
-		memset(dev->isoc_ctl.transfer_buffer[i], 0, sb_size);
+		urb->transfer_dma = dev->urb_dma[i];
+		dev->isoc_ctl.transfer_buffer[i] = dev->urb_buffer[i];
 
 		usb_fill_bulk_urb(urb, dev->udev, pipe,
 				  dev->isoc_ctl.transfer_buffer[i], sb_size,
@@ -1826,6 +1895,9 @@ int tm6000_v4l2_unregister(struct tm6000_core *dev)
 {
 	video_unregister_device(dev->vfd);
 
+	/* if URB buffers are still allocated free them now */
+	tm6000_free_urb_buffers(dev);
+
 	if (dev->radio_dev) {
 		if (video_is_registered(dev->radio_dev))
 			video_unregister_device(dev->radio_dev);
@@ -1851,3 +1923,5 @@ MODULE_PARM_DESC(debug, "activates debug info");
 module_param(vid_limit, int, 0644);
 MODULE_PARM_DESC(vid_limit, "capture memory limit in megabytes");
 
+module_param(keep_urb, bool, 0);
+MODULE_PARM_DESC(keep_urb, "Keep urb buffers allocated even when the device is closed by the user");
diff --git a/drivers/media/usb/tm6000/tm6000.h b/drivers/media/usb/tm6000/tm6000.h
index 6df418658c9c..173dcd7a7284 100644
--- a/drivers/media/usb/tm6000/tm6000.h
+++ b/drivers/media/usb/tm6000/tm6000.h
@@ -264,6 +264,11 @@ struct tm6000_core {
 
 	spinlock_t                   slock;
 
+	/* urb dma buffers */
+	char				**urb_buffer;
+	dma_addr_t			*urb_dma;
+	unsigned int			urb_size;
+
 	unsigned long quirks;
 };