1 files changed, 29 insertions, 28 deletions

diff --git a/drivers/net/can/usb/kvaser_usb.c b/drivers/net/can/usb/kvaser_usb.c
index 541fb7a05625..7af379ca861b 100644
--- a/drivers/net/can/usb/kvaser_usb.c
+++ b/drivers/net/can/usb/kvaser_usb.c
@@ -520,10 +520,10 @@ static void kvaser_usb_tx_acknowledge(const struct kvaser_usb *dev,
 		skb = alloc_can_err_skb(priv->netdev, &cf);
 		if (skb) {
 			cf->can_id |= CAN_ERR_RESTARTED;
-			netif_rx(skb);
 
 			stats->rx_packets++;
 			stats->rx_bytes += cf->can_dlc;
+			netif_rx(skb);
 		} else {
 			netdev_err(priv->netdev,
 				   "No memory left for err_skb\n");
@@ -587,7 +587,7 @@ static int kvaser_usb_simple_msg_async(struct kvaser_usb_net_priv *priv,
 			  usb_sndbulkpipe(dev->udev,
 					  dev->bulk_out->bEndpointAddress),
 			  buf, msg->len,
-			  kvaser_usb_simple_msg_callback, priv);
+			  kvaser_usb_simple_msg_callback, netdev);
 	usb_anchor_urb(urb, &priv->tx_submitted);
 
 	err = usb_submit_urb(urb, GFP_ATOMIC);
@@ -662,11 +662,6 @@ static void kvaser_usb_rx_error(const struct kvaser_usb *dev,
 	priv = dev->nets[channel];
 	stats = &priv->netdev->stats;
 
-	if (status & M16C_STATE_BUS_RESET) {
-		kvaser_usb_unlink_tx_urbs(priv);
-		return;
-	}
-
 	skb = alloc_can_err_skb(priv->netdev, &cf);
 	if (!skb) {
 		stats->rx_dropped++;
@@ -677,7 +672,7 @@ static void kvaser_usb_rx_error(const struct kvaser_usb *dev,
 
 	netdev_dbg(priv->netdev, "Error status: 0x%02x\n", status);
 
-	if (status & M16C_STATE_BUS_OFF) {
+	if (status & (M16C_STATE_BUS_OFF | M16C_STATE_BUS_RESET)) {
 		cf->can_id |= CAN_ERR_BUSOFF;
 
 		priv->can.can_stats.bus_off++;
@@ -703,9 +698,7 @@ static void kvaser_usb_rx_error(const struct kvaser_usb *dev,
 		}
 
 		new_state = CAN_STATE_ERROR_PASSIVE;
-	}
-
-	if (status == M16C_STATE_BUS_ERROR) {
+	} else if (status & M16C_STATE_BUS_ERROR) {
 		if ((priv->can.state < CAN_STATE_ERROR_WARNING) &&
 		    ((txerr >= 96) || (rxerr >= 96))) {
 			cf->can_id |= CAN_ERR_CRTL;
@@ -715,7 +708,8 @@ static void kvaser_usb_rx_error(const struct kvaser_usb *dev,
 
 			priv->can.can_stats.error_warning++;
 			new_state = CAN_STATE_ERROR_WARNING;
-		} else if (priv->can.state > CAN_STATE_ERROR_ACTIVE) {
+		} else if ((priv->can.state > CAN_STATE_ERROR_ACTIVE) &&
+			   ((txerr < 96) && (rxerr < 96))) {
 			cf->can_id |= CAN_ERR_PROT;
 			cf->data[2] = CAN_ERR_PROT_ACTIVE;
 
@@ -770,10 +764,9 @@ static void kvaser_usb_rx_error(const struct kvaser_usb *dev,
 
 	priv->can.state = new_state;
 
-	netif_rx(skb);
-
 	stats->rx_packets++;
 	stats->rx_bytes += cf->can_dlc;
+	netif_rx(skb);
 }
 
 static void kvaser_usb_rx_can_err(const struct kvaser_usb_net_priv *priv,
@@ -805,10 +798,9 @@ static void kvaser_usb_rx_can_err(const struct kvaser_usb_net_priv *priv,
 		stats->rx_over_errors++;
 		stats->rx_errors++;
 
-		netif_rx(skb);
-
 		stats->rx_packets++;
 		stats->rx_bytes += cf->can_dlc;
+		netif_rx(skb);
 	}
 }
 
@@ -887,10 +879,9 @@ static void kvaser_usb_rx_can_msg(const struct kvaser_usb *dev,
 			       cf->can_dlc);
 	}
 
-	netif_rx(skb);
-
 	stats->rx_packets++;
 	stats->rx_bytes += cf->can_dlc;
+	netif_rx(skb);
 }
 
 static void kvaser_usb_start_chip_reply(const struct kvaser_usb *dev,
@@ -1246,6 +1237,9 @@ static int kvaser_usb_close(struct net_device *netdev)
 	if (err)
 		netdev_warn(netdev, "Cannot stop device, error %d\n", err);
 
+	/* reset tx contexts */
+	kvaser_usb_unlink_tx_urbs(priv);
+
 	priv->can.state = CAN_STATE_STOPPED;
 	close_candev(priv->netdev);
 
@@ -1294,12 +1288,14 @@ static netdev_tx_t kvaser_usb_start_xmit(struct sk_buff *skb,
 	if (!urb) {
 		netdev_err(netdev, "No memory left for URBs\n");
 		stats->tx_dropped++;
-		goto nourbmem;
+		dev_kfree_skb(skb);
+		return NETDEV_TX_OK;
 	}
 
 	buf = kmalloc(sizeof(struct kvaser_msg), GFP_ATOMIC);
 	if (!buf) {
 		stats->tx_dropped++;
+		dev_kfree_skb(skb);
 		goto nobufmem;
 	}
 
@@ -1334,6 +1330,7 @@ static netdev_tx_t kvaser_usb_start_xmit(struct sk_buff *skb,
 		}
 	}
 
+	/* This should never happen; it implies a flow control bug */
 	if (!context) {
 		netdev_warn(netdev, "cannot find free context\n");
 		ret =  NETDEV_TX_BUSY;
@@ -1364,9 +1361,6 @@ static netdev_tx_t kvaser_usb_start_xmit(struct sk_buff *skb,
 	if (unlikely(err)) {
 		can_free_echo_skb(netdev, context->echo_index);
 
-		skb = NULL; /* set to NULL to avoid double free in
-			     * dev_kfree_skb(skb) */
-
 		atomic_dec(&priv->active_tx_urbs);
 		usb_unanchor_urb(urb);
 
@@ -1388,8 +1382,6 @@ releasebuf:
 	kfree(buf);
 nobufmem:
 	usb_free_urb(urb);
-nourbmem:
-	dev_kfree_skb(skb);
 	return ret;
 }
 
@@ -1502,6 +1494,10 @@ static int kvaser_usb_init_one(struct usb_interface *intf,
 	struct kvaser_usb_net_priv *priv;
 	int i, err;
 
+	err = kvaser_usb_send_simple_msg(dev, CMD_RESET_CHIP, channel);
+	if (err)
+		return err;
+
 	netdev = alloc_candev(sizeof(*priv), MAX_TX_URBS);
 	if (!netdev) {
 		dev_err(&intf->dev, "Cannot alloc candev\n");
@@ -1588,7 +1584,7 @@ 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)
@@ -1606,10 +1602,15 @@ static int kvaser_usb_probe(struct usb_interface *intf,
 
 	usb_set_intfdata(intf, dev);
 
-	for (i = 0; i < MAX_NET_DEVICES; i++)
-		kvaser_usb_send_simple_msg(dev, CMD_RESET_CHIP, i);
+	/* 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);
 
-	err = kvaser_usb_get_software_info(dev);
 	if (err) {
 		dev_err(&intf->dev,
 			"Cannot get software infos, error %d\n", err);