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);