can: kvaser_usb: Retry the first bulk transfer on -ETIMEDOUT

On some x86 laptops, plugging a Kvaser device again after an unplug makes the firmware always ignore the very first command. For such a case, provide some room for retries instead of completely exiting the driver init code. Signed-off-by: Ahmed S. Darwish <[email protected]> Cc: linux-stable <[email protected]> Signed-off-by: Marc Kleine-Budde <[email protected]>
XGWang0 · Jan 27, 2015 · 14c10c2 · 14c10c2
1 parent 3803fa6
commit 14c10c2
Showing 1 changed file with 10 additions and 2 deletions.
diff --git a/drivers/net/can/usb/kvaser_usb.c b/drivers/net/can/usb/kvaser_usb.c
@@ -1585,7 +1585,7 @@ static int kvaser_usb_probe(struct usb_interface *intf,
 {
 	struct kvaser_usb *dev;
 	int err = -ENOMEM;
-	int i;
+	int i, retry = 3;
 
 	dev = devm_kzalloc(&intf->dev, sizeof(*dev), GFP_KERNEL);
 	if (!dev)
@@ -1603,7 +1603,15 @@ static int kvaser_usb_probe(struct usb_interface *intf,
 
 	usb_set_intfdata(intf, dev);
 
-	err = kvaser_usb_get_software_info(dev);
+	/* On some x86 laptops, plugging a Kvaser device again after
+	 * an unplug makes the firmware always ignore the very first
+	 * command. For such a case, provide some room for retries
+	 * instead of completely exiting the driver.
+	 */
+	do {
+		err = kvaser_usb_get_software_info(dev);
+	} while (--retry && err == -ETIMEDOUT);
+
 	if (err) {
 		dev_err(&intf->dev,
 			"Cannot get software infos, error %d\n", err);