Merge commit 'origin/master' into next

1 files changed, 17 insertions, 0 deletions

diff --git a/drivers/media/video/au0828/au0828-core.c b/drivers/media/video/au0828/au0828-core.c
index a1e4c0d769a..3544a2f12f1 100644
--- a/drivers/media/video/au0828/au0828-core.c
+++ b/drivers/media/video/au0828/au0828-core.c
@@ -36,6 +36,11 @@ int au0828_debug;
 module_param_named(debug, au0828_debug, int, 0644);
 MODULE_PARM_DESC(debug, "enable debug messages");
 
+static unsigned int disable_usb_speed_check;
+module_param(disable_usb_speed_check, int, 0444);
+MODULE_PARM_DESC(disable_usb_speed_check,
+		 "override min bandwidth requirement of 480M bps");
+
 #define _AU0828_BULKPIPE 0x03
 #define _BULKPIPESIZE 0xffff
 
@@ -181,6 +186,18 @@ static int au0828_usb_probe(struct usb_interface *interface,
 		le16_to_cpu(usbdev->descriptor.idProduct),
 		ifnum);
 
+	/*
+	 * Make sure we have 480 Mbps of bandwidth, otherwise things like
+	 * video stream wouldn't likely work, since 12 Mbps is generally
+	 * not enough even for most Digital TV streams.
+	 */
+	if (usbdev->speed != USB_SPEED_HIGH && disable_usb_speed_check == 0) {
+		printk(KERN_ERR "au0828: Device initialization failed.\n");
+		printk(KERN_ERR "au0828: Device must be connected to a "
+		       "high-speed USB 2.0 port.\n");
+		return -ENODEV;
+	}
+
 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 	if (dev == NULL) {
 		printk(KERN_ERR "%s() Unable to allocate memory\n", __func__);