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path: root/drivers/net/can/usb/kvaser_usb.c
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Diffstat (limited to 'drivers/net/can/usb/kvaser_usb.c')
-rw-r--r--drivers/net/can/usb/kvaser_usb.c74
1 files changed, 48 insertions, 26 deletions
diff --git a/drivers/net/can/usb/kvaser_usb.c b/drivers/net/can/usb/kvaser_usb.c
index 541fb7a05625..5d777956ae1f 100644
--- a/drivers/net/can/usb/kvaser_usb.c
+++ b/drivers/net/can/usb/kvaser_usb.c
@@ -12,6 +12,7 @@
* Copyright (C) 2012 Olivier Sobrie <olivier@sobrie.be>
*/
+#include <linux/kernel.h>
#include <linux/completion.h>
#include <linux/module.h>
#include <linux/netdevice.h>
@@ -403,8 +404,15 @@ static int kvaser_usb_wait_msg(const struct kvaser_usb *dev, u8 id,
while (pos <= actual_len - MSG_HEADER_LEN) {
tmp = buf + pos;
- if (!tmp->len)
- break;
+ /* Handle messages crossing the USB endpoint max packet
+ * size boundary. Check kvaser_usb_read_bulk_callback()
+ * for further details.
+ */
+ if (tmp->len == 0) {
+ pos = round_up(pos,
+ dev->bulk_in->wMaxPacketSize);
+ continue;
+ }
if (pos + tmp->len > actual_len) {
dev_err(dev->udev->dev.parent,
@@ -587,7 +595,7 @@ 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 +670,6 @@ 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 +680,7 @@ 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 +706,7 @@ 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 +716,8 @@ 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;
@@ -989,8 +991,19 @@ static void kvaser_usb_read_bulk_callback(struct urb *urb)
while (pos <= urb->actual_length - MSG_HEADER_LEN) {
msg = urb->transfer_buffer + pos;
- if (!msg->len)
- break;
+ /* The Kvaser firmware can only read and write messages that
+ * does not cross the USB's endpoint wMaxPacketSize boundary.
+ * If a follow-up command crosses such boundary, firmware puts
+ * a placeholder zero-length command in its place then aligns
+ * the real command to the next max packet size.
+ *
+ * Handle such cases or we're going to miss a significant
+ * number of events in case of a heavy rx load on the bus.
+ */
+ if (msg->len == 0) {
+ pos = round_up(pos, dev->bulk_in->wMaxPacketSize);
+ continue;
+ }
if (pos + msg->len > urb->actual_length) {
dev_err(dev->udev->dev.parent, "Format error\n");
@@ -998,7 +1011,6 @@ static void kvaser_usb_read_bulk_callback(struct urb *urb)
}
kvaser_usb_handle_message(dev, msg);
-
pos += msg->len;
}
@@ -1246,6 +1258,9 @@ 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 +1309,14 @@ 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 +1351,7 @@ 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 +1382,6 @@ 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 +1403,6 @@ releasebuf:
kfree(buf);
nobufmem:
usb_free_urb(urb);
-nourbmem:
- dev_kfree_skb(skb);
return ret;
}
@@ -1502,6 +1515,10 @@ 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 +1605,7 @@ 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 +1623,15 @@ 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);
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-25 21:09:38 +0000