can: kvaser_usb: add retries/timeout to kvaser_usb_wait_msg()

On some Kvaser hardware, the firmware returns extra messages after the
request for card info. For instance on a Leaf Light v2:
  --> CMD_GET_CARD_INFO
  <-- CMD_USB_THROTTLE
  <-- CMD_GET_CARD_INFO2
  <-- CMD_GET_CARD_INFO_REQ
When it happens, the probing function fails because we only read
the first usb message.

To overcome this issue, we add a mechanism of retries to the
kvaser_usb_wait_msg() function.

I tested this patch with the following hardware:
 - Kvaser Leaf Light
 - Kvaser Leaf Light v2
 - Kvaser USBCan R

This patch is necessary for the Leaf Light v2 hardware.
Signed-off-by: Olivier Sobrie <olivier@sobrie.be>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

drivers/net/can/usb/kvaser_usb.c

@@ -379,12 +379,14 @@ static int kvaser_usb_wait_msg(const struct kvaser_usb *dev, u8 id,
 	void *buf;
 	int actual_len;
 	int err;
-	int pos = 0;
+	int pos;
+	unsigned long to = jiffies + msecs_to_jiffies(USB_RECV_TIMEOUT);
 
 	buf = kzalloc(RX_BUFFER_SIZE, GFP_KERNEL);
 	if (!buf)
 		return -ENOMEM;
 
+	do {
 		err = usb_bulk_msg(dev->udev,
 				   usb_rcvbulkpipe(dev->udev,
 					dev->bulk_in->bEndpointAddress),
@@ -393,6 +395,7 @@ static int kvaser_usb_wait_msg(const struct kvaser_usb *dev, u8 id,
 		if (err < 0)
 			goto end;
 
+		pos = 0;
 		while (pos <= actual_len - MSG_HEADER_LEN) {
 			tmp = buf + pos;
 
@@ -400,7 +403,8 @@ static int kvaser_usb_wait_msg(const struct kvaser_usb *dev, u8 id,
 				break;
 
 			if (pos + tmp->len > actual_len) {
-			dev_err(dev->udev->dev.parent, "Format error\n");
+				dev_err(dev->udev->dev.parent,
+					"Format error\n");
 				break;
 			}
 
@@ -411,6 +415,7 @@ static int kvaser_usb_wait_msg(const struct kvaser_usb *dev, u8 id,
 
 			pos += tmp->len;
 		}
+	} while (time_before(jiffies, to));
 
 	err = -EINVAL;