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path: root/drivers/net/usb/usbnet.c
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Diffstat (limited to 'drivers/net/usb/usbnet.c')
-rw-r--r--drivers/net/usb/usbnet.c2107
1 files changed, 2107 insertions, 0 deletions
diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
new file mode 100644
index 000000000..3c86b1072
--- /dev/null
+++ b/drivers/net/usb/usbnet.c
@@ -0,0 +1,2107 @@
+/*
+ * USB Network driver infrastructure
+ * Copyright (C) 2000-2005 by David Brownell
+ * Copyright (C) 2003-2005 David Hollis <dhollis@davehollis.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ * This is a generic "USB networking" framework that works with several
+ * kinds of full and high speed networking devices: host-to-host cables,
+ * smart usb peripherals, and actual Ethernet adapters.
+ *
+ * These devices usually differ in terms of control protocols (if they
+ * even have one!) and sometimes they define new framing to wrap or batch
+ * Ethernet packets. Otherwise, they talk to USB pretty much the same,
+ * so interface (un)binding, endpoint I/O queues, fault handling, and other
+ * issues can usefully be addressed by this framework.
+ */
+
+// #define DEBUG // error path messages, extra info
+// #define VERBOSE // more; success messages
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/ctype.h>
+#include <linux/ethtool.h>
+#include <linux/workqueue.h>
+#include <linux/mii.h>
+#include <linux/usb.h>
+#include <linux/usb/usbnet.h>
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/pm_runtime.h>
+
+#define DRIVER_VERSION "22-Aug-2005"
+
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * Nineteen USB 1.1 max size bulk transactions per frame (ms), max.
+ * Several dozen bytes of IPv4 data can fit in two such transactions.
+ * One maximum size Ethernet packet takes twenty four of them.
+ * For high speed, each frame comfortably fits almost 36 max size
+ * Ethernet packets (so queues should be bigger).
+ *
+ * The goal is to let the USB host controller be busy for 5msec or
+ * more before an irq is required, under load. Jumbograms change
+ * the equation.
+ */
+#define MAX_QUEUE_MEMORY (60 * 1518)
+#define RX_QLEN(dev) ((dev)->rx_qlen)
+#define TX_QLEN(dev) ((dev)->tx_qlen)
+
+// reawaken network queue this soon after stopping; else watchdog barks
+#define TX_TIMEOUT_JIFFIES (5*HZ)
+
+/* throttle rx/tx briefly after some faults, so hub_wq might disconnect()
+ * us (it polls at HZ/4 usually) before we report too many false errors.
+ */
+#define THROTTLE_JIFFIES (HZ/8)
+
+// between wakeups
+#define UNLINK_TIMEOUT_MS 3
+
+/*-------------------------------------------------------------------------*/
+
+// randomly generated ethernet address
+static u8 node_id [ETH_ALEN];
+
+static const char driver_name [] = "usbnet";
+
+/* use ethtool to change the level for any given device */
+static int msg_level = -1;
+module_param (msg_level, int, 0);
+MODULE_PARM_DESC (msg_level, "Override default message level");
+
+/*-------------------------------------------------------------------------*/
+
+/* handles CDC Ethernet and many other network "bulk data" interfaces */
+int usbnet_get_endpoints(struct usbnet *dev, struct usb_interface *intf)
+{
+ int tmp;
+ struct usb_host_interface *alt = NULL;
+ struct usb_host_endpoint *in = NULL, *out = NULL;
+ struct usb_host_endpoint *status = NULL;
+
+ for (tmp = 0; tmp < intf->num_altsetting; tmp++) {
+ unsigned ep;
+
+ in = out = status = NULL;
+ alt = intf->altsetting + tmp;
+
+ /* take the first altsetting with in-bulk + out-bulk;
+ * remember any status endpoint, just in case;
+ * ignore other endpoints and altsettings.
+ */
+ for (ep = 0; ep < alt->desc.bNumEndpoints; ep++) {
+ struct usb_host_endpoint *e;
+ int intr = 0;
+
+ e = alt->endpoint + ep;
+ switch (e->desc.bmAttributes) {
+ case USB_ENDPOINT_XFER_INT:
+ if (!usb_endpoint_dir_in(&e->desc))
+ continue;
+ intr = 1;
+ /* FALLTHROUGH */
+ case USB_ENDPOINT_XFER_BULK:
+ break;
+ default:
+ continue;
+ }
+ if (usb_endpoint_dir_in(&e->desc)) {
+ if (!intr && !in)
+ in = e;
+ else if (intr && !status)
+ status = e;
+ } else {
+ if (!out)
+ out = e;
+ }
+ }
+ if (in && out)
+ break;
+ }
+ if (!alt || !in || !out)
+ return -EINVAL;
+
+ if (alt->desc.bAlternateSetting != 0 ||
+ !(dev->driver_info->flags & FLAG_NO_SETINT)) {
+ tmp = usb_set_interface (dev->udev, alt->desc.bInterfaceNumber,
+ alt->desc.bAlternateSetting);
+ if (tmp < 0)
+ return tmp;
+ }
+
+ dev->in = usb_rcvbulkpipe (dev->udev,
+ in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
+ dev->out = usb_sndbulkpipe (dev->udev,
+ out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
+ dev->status = status;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(usbnet_get_endpoints);
+
+int usbnet_get_ethernet_addr(struct usbnet *dev, int iMACAddress)
+{
+ int tmp = -1, ret;
+ unsigned char buf [13];
+
+ ret = usb_string(dev->udev, iMACAddress, buf, sizeof buf);
+ if (ret == 12)
+ tmp = hex2bin(dev->net->dev_addr, buf, 6);
+ if (tmp < 0) {
+ dev_dbg(&dev->udev->dev,
+ "bad MAC string %d fetch, %d\n", iMACAddress, tmp);
+ if (ret >= 0)
+ ret = -EINVAL;
+ return ret;
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(usbnet_get_ethernet_addr);
+
+static void intr_complete (struct urb *urb)
+{
+ struct usbnet *dev = urb->context;
+ int status = urb->status;
+
+ switch (status) {
+ /* success */
+ case 0:
+ dev->driver_info->status(dev, urb);
+ break;
+
+ /* software-driven interface shutdown */
+ case -ENOENT: /* urb killed */
+ case -ESHUTDOWN: /* hardware gone */
+ netif_dbg(dev, ifdown, dev->net,
+ "intr shutdown, code %d\n", status);
+ return;
+
+ /* NOTE: not throttling like RX/TX, since this endpoint
+ * already polls infrequently
+ */
+ default:
+ netdev_dbg(dev->net, "intr status %d\n", status);
+ break;
+ }
+
+ status = usb_submit_urb (urb, GFP_ATOMIC);
+ if (status != 0)
+ netif_err(dev, timer, dev->net,
+ "intr resubmit --> %d\n", status);
+}
+
+static int init_status (struct usbnet *dev, struct usb_interface *intf)
+{
+ char *buf = NULL;
+ unsigned pipe = 0;
+ unsigned maxp;
+ unsigned period;
+
+ if (!dev->driver_info->status)
+ return 0;
+
+ pipe = usb_rcvintpipe (dev->udev,
+ dev->status->desc.bEndpointAddress
+ & USB_ENDPOINT_NUMBER_MASK);
+ maxp = usb_maxpacket (dev->udev, pipe, 0);
+
+ /* avoid 1 msec chatter: min 8 msec poll rate */
+ period = max ((int) dev->status->desc.bInterval,
+ (dev->udev->speed == USB_SPEED_HIGH) ? 7 : 3);
+
+ buf = kmalloc (maxp, GFP_KERNEL);
+ if (buf) {
+ dev->interrupt = usb_alloc_urb (0, GFP_KERNEL);
+ if (!dev->interrupt) {
+ kfree (buf);
+ return -ENOMEM;
+ } else {
+ usb_fill_int_urb(dev->interrupt, dev->udev, pipe,
+ buf, maxp, intr_complete, dev, period);
+ dev->interrupt->transfer_flags |= URB_FREE_BUFFER;
+ dev_dbg(&intf->dev,
+ "status ep%din, %d bytes period %d\n",
+ usb_pipeendpoint(pipe), maxp, period);
+ }
+ }
+ return 0;
+}
+
+/* Submit the interrupt URB if not previously submitted, increasing refcount */
+int usbnet_status_start(struct usbnet *dev, gfp_t mem_flags)
+{
+ int ret = 0;
+
+ WARN_ON_ONCE(dev->interrupt == NULL);
+ if (dev->interrupt) {
+ mutex_lock(&dev->interrupt_mutex);
+
+ if (++dev->interrupt_count == 1)
+ ret = usb_submit_urb(dev->interrupt, mem_flags);
+
+ dev_dbg(&dev->udev->dev, "incremented interrupt URB count to %d\n",
+ dev->interrupt_count);
+ mutex_unlock(&dev->interrupt_mutex);
+ }
+ return ret;
+}
+EXPORT_SYMBOL_GPL(usbnet_status_start);
+
+/* For resume; submit interrupt URB if previously submitted */
+static int __usbnet_status_start_force(struct usbnet *dev, gfp_t mem_flags)
+{
+ int ret = 0;
+
+ mutex_lock(&dev->interrupt_mutex);
+ if (dev->interrupt_count) {
+ ret = usb_submit_urb(dev->interrupt, mem_flags);
+ dev_dbg(&dev->udev->dev,
+ "submitted interrupt URB for resume\n");
+ }
+ mutex_unlock(&dev->interrupt_mutex);
+ return ret;
+}
+
+/* Kill the interrupt URB if all submitters want it killed */
+void usbnet_status_stop(struct usbnet *dev)
+{
+ if (dev->interrupt) {
+ mutex_lock(&dev->interrupt_mutex);
+ WARN_ON(dev->interrupt_count == 0);
+
+ if (dev->interrupt_count && --dev->interrupt_count == 0)
+ usb_kill_urb(dev->interrupt);
+
+ dev_dbg(&dev->udev->dev,
+ "decremented interrupt URB count to %d\n",
+ dev->interrupt_count);
+ mutex_unlock(&dev->interrupt_mutex);
+ }
+}
+EXPORT_SYMBOL_GPL(usbnet_status_stop);
+
+/* For suspend; always kill interrupt URB */
+static void __usbnet_status_stop_force(struct usbnet *dev)
+{
+ if (dev->interrupt) {
+ mutex_lock(&dev->interrupt_mutex);
+ usb_kill_urb(dev->interrupt);
+ dev_dbg(&dev->udev->dev, "killed interrupt URB for suspend\n");
+ mutex_unlock(&dev->interrupt_mutex);
+ }
+}
+
+/* Passes this packet up the stack, updating its accounting.
+ * Some link protocols batch packets, so their rx_fixup paths
+ * can return clones as well as just modify the original skb.
+ */
+void usbnet_skb_return (struct usbnet *dev, struct sk_buff *skb)
+{
+ int status;
+
+ if (test_bit(EVENT_RX_PAUSED, &dev->flags)) {
+ skb_queue_tail(&dev->rxq_pause, skb);
+ return;
+ }
+
+ skb->protocol = eth_type_trans (skb, dev->net);
+ dev->net->stats.rx_packets++;
+ dev->net->stats.rx_bytes += skb->len;
+
+ netif_dbg(dev, rx_status, dev->net, "< rx, len %zu, type 0x%x\n",
+ skb->len + sizeof (struct ethhdr), skb->protocol);
+ memset (skb->cb, 0, sizeof (struct skb_data));
+
+ if (skb_defer_rx_timestamp(skb))
+ return;
+
+ status = netif_rx (skb);
+ if (status != NET_RX_SUCCESS)
+ netif_dbg(dev, rx_err, dev->net,
+ "netif_rx status %d\n", status);
+}
+EXPORT_SYMBOL_GPL(usbnet_skb_return);
+
+/* must be called if hard_mtu or rx_urb_size changed */
+void usbnet_update_max_qlen(struct usbnet *dev)
+{
+ enum usb_device_speed speed = dev->udev->speed;
+
+ switch (speed) {
+ case USB_SPEED_HIGH:
+ dev->rx_qlen = MAX_QUEUE_MEMORY / dev->rx_urb_size;
+ dev->tx_qlen = MAX_QUEUE_MEMORY / dev->hard_mtu;
+ break;
+ case USB_SPEED_SUPER:
+ /*
+ * Not take default 5ms qlen for super speed HC to
+ * save memory, and iperf tests show 2.5ms qlen can
+ * work well
+ */
+ dev->rx_qlen = 5 * MAX_QUEUE_MEMORY / dev->rx_urb_size;
+ dev->tx_qlen = 5 * MAX_QUEUE_MEMORY / dev->hard_mtu;
+ break;
+ default:
+ dev->rx_qlen = dev->tx_qlen = 4;
+ }
+}
+EXPORT_SYMBOL_GPL(usbnet_update_max_qlen);
+
+
+/*-------------------------------------------------------------------------
+ *
+ * Network Device Driver (peer link to "Host Device", from USB host)
+ *
+ *-------------------------------------------------------------------------*/
+
+int usbnet_change_mtu (struct net_device *net, int new_mtu)
+{
+ struct usbnet *dev = netdev_priv(net);
+ int ll_mtu = new_mtu + net->hard_header_len;
+ int old_hard_mtu = dev->hard_mtu;
+ int old_rx_urb_size = dev->rx_urb_size;
+
+ if (new_mtu <= 0)
+ return -EINVAL;
+ // no second zero-length packet read wanted after mtu-sized packets
+ if ((ll_mtu % dev->maxpacket) == 0)
+ return -EDOM;
+ net->mtu = new_mtu;
+
+ dev->hard_mtu = net->mtu + net->hard_header_len;
+ if (dev->rx_urb_size == old_hard_mtu) {
+ dev->rx_urb_size = dev->hard_mtu;
+ if (dev->rx_urb_size > old_rx_urb_size)
+ usbnet_unlink_rx_urbs(dev);
+ }
+
+ /* max qlen depend on hard_mtu and rx_urb_size */
+ usbnet_update_max_qlen(dev);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(usbnet_change_mtu);
+
+/* The caller must hold list->lock */
+static void __usbnet_queue_skb(struct sk_buff_head *list,
+ struct sk_buff *newsk, enum skb_state state)
+{
+ struct skb_data *entry = (struct skb_data *) newsk->cb;
+
+ __skb_queue_tail(list, newsk);
+ entry->state = state;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from
+ * completion callbacks. 2.5 should have fixed those bugs...
+ */
+
+static enum skb_state defer_bh(struct usbnet *dev, struct sk_buff *skb,
+ struct sk_buff_head *list, enum skb_state state)
+{
+ unsigned long flags;
+ enum skb_state old_state;
+ struct skb_data *entry = (struct skb_data *) skb->cb;
+
+ spin_lock_irqsave(&list->lock, flags);
+ old_state = entry->state;
+ entry->state = state;
+ __skb_unlink(skb, list);
+ spin_unlock(&list->lock);
+ spin_lock(&dev->done.lock);
+ __skb_queue_tail(&dev->done, skb);
+ if (dev->done.qlen == 1)
+ tasklet_schedule(&dev->bh);
+ spin_unlock_irqrestore(&dev->done.lock, flags);
+ return old_state;
+}
+
+/* some work can't be done in tasklets, so we use keventd
+ *
+ * NOTE: annoying asymmetry: if it's active, schedule_work() fails,
+ * but tasklet_schedule() doesn't. hope the failure is rare.
+ */
+void usbnet_defer_kevent (struct usbnet *dev, int work)
+{
+ set_bit (work, &dev->flags);
+ if (!schedule_work (&dev->kevent)) {
+ if (net_ratelimit())
+ netdev_err(dev->net, "kevent %d may have been dropped\n", work);
+ } else {
+ netdev_dbg(dev->net, "kevent %d scheduled\n", work);
+ }
+}
+EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
+
+/*-------------------------------------------------------------------------*/
+
+static void rx_complete (struct urb *urb);
+
+static int rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags)
+{
+ struct sk_buff *skb;
+ struct skb_data *entry;
+ int retval = 0;
+ unsigned long lockflags;
+ size_t size = dev->rx_urb_size;
+
+ /* prevent rx skb allocation when error ratio is high */
+ if (test_bit(EVENT_RX_KILL, &dev->flags)) {
+ usb_free_urb(urb);
+ return -ENOLINK;
+ }
+
+ skb = __netdev_alloc_skb_ip_align(dev->net, size, flags);
+ if (!skb) {
+ netif_dbg(dev, rx_err, dev->net, "no rx skb\n");
+ usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
+ usb_free_urb (urb);
+ return -ENOMEM;
+ }
+
+ entry = (struct skb_data *) skb->cb;
+ entry->urb = urb;
+ entry->dev = dev;
+ entry->length = 0;
+
+ usb_fill_bulk_urb (urb, dev->udev, dev->in,
+ skb->data, size, rx_complete, skb);
+
+ spin_lock_irqsave (&dev->rxq.lock, lockflags);
+
+ if (netif_running (dev->net) &&
+ netif_device_present (dev->net) &&
+ !test_bit (EVENT_RX_HALT, &dev->flags) &&
+ !test_bit (EVENT_DEV_ASLEEP, &dev->flags)) {
+ switch (retval = usb_submit_urb (urb, GFP_ATOMIC)) {
+ case -EPIPE:
+ usbnet_defer_kevent (dev, EVENT_RX_HALT);
+ break;
+ case -ENOMEM:
+ usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
+ break;
+ case -ENODEV:
+ netif_dbg(dev, ifdown, dev->net, "device gone\n");
+ netif_device_detach (dev->net);
+ break;
+ case -EHOSTUNREACH:
+ retval = -ENOLINK;
+ break;
+ default:
+ netif_dbg(dev, rx_err, dev->net,
+ "rx submit, %d\n", retval);
+ tasklet_schedule (&dev->bh);
+ break;
+ case 0:
+ __usbnet_queue_skb(&dev->rxq, skb, rx_start);
+ }
+ } else {
+ netif_dbg(dev, ifdown, dev->net, "rx: stopped\n");
+ retval = -ENOLINK;
+ }
+ spin_unlock_irqrestore (&dev->rxq.lock, lockflags);
+ if (retval) {
+ dev_kfree_skb_any (skb);
+ usb_free_urb (urb);
+ }
+ return retval;
+}
+
+
+/*-------------------------------------------------------------------------*/
+
+static inline void rx_process (struct usbnet *dev, struct sk_buff *skb)
+{
+ if (dev->driver_info->rx_fixup &&
+ !dev->driver_info->rx_fixup (dev, skb)) {
+ /* With RX_ASSEMBLE, rx_fixup() must update counters */
+ if (!(dev->driver_info->flags & FLAG_RX_ASSEMBLE))
+ dev->net->stats.rx_errors++;
+ goto done;
+ }
+ // else network stack removes extra byte if we forced a short packet
+
+ /* all data was already cloned from skb inside the driver */
+ if (dev->driver_info->flags & FLAG_MULTI_PACKET)
+ goto done;
+
+ if (skb->len < ETH_HLEN) {
+ dev->net->stats.rx_errors++;
+ dev->net->stats.rx_length_errors++;
+ netif_dbg(dev, rx_err, dev->net, "rx length %d\n", skb->len);
+ } else {
+ usbnet_skb_return(dev, skb);
+ return;
+ }
+
+done:
+ skb_queue_tail(&dev->done, skb);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void rx_complete (struct urb *urb)
+{
+ struct sk_buff *skb = (struct sk_buff *) urb->context;
+ struct skb_data *entry = (struct skb_data *) skb->cb;
+ struct usbnet *dev = entry->dev;
+ int urb_status = urb->status;
+ enum skb_state state;
+
+ skb_put (skb, urb->actual_length);
+ state = rx_done;
+ entry->urb = NULL;
+
+ switch (urb_status) {
+ /* success */
+ case 0:
+ break;
+
+ /* stalls need manual reset. this is rare ... except that
+ * when going through USB 2.0 TTs, unplug appears this way.
+ * we avoid the highspeed version of the ETIMEDOUT/EILSEQ
+ * storm, recovering as needed.
+ */
+ case -EPIPE:
+ dev->net->stats.rx_errors++;
+ usbnet_defer_kevent (dev, EVENT_RX_HALT);
+ // FALLTHROUGH
+
+ /* software-driven interface shutdown */
+ case -ECONNRESET: /* async unlink */
+ case -ESHUTDOWN: /* hardware gone */
+ netif_dbg(dev, ifdown, dev->net,
+ "rx shutdown, code %d\n", urb_status);
+ goto block;
+
+ /* we get controller i/o faults during hub_wq disconnect() delays.
+ * throttle down resubmits, to avoid log floods; just temporarily,
+ * so we still recover when the fault isn't a hub_wq delay.
+ */
+ case -EPROTO:
+ case -ETIME:
+ case -EILSEQ:
+ dev->net->stats.rx_errors++;
+ if (!timer_pending (&dev->delay)) {
+ mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES);
+ netif_dbg(dev, link, dev->net,
+ "rx throttle %d\n", urb_status);
+ }
+block:
+ state = rx_cleanup;
+ entry->urb = urb;
+ urb = NULL;
+ break;
+
+ /* data overrun ... flush fifo? */
+ case -EOVERFLOW:
+ dev->net->stats.rx_over_errors++;
+ // FALLTHROUGH
+
+ default:
+ state = rx_cleanup;
+ dev->net->stats.rx_errors++;
+ netif_dbg(dev, rx_err, dev->net, "rx status %d\n", urb_status);
+ break;
+ }
+
+ /* stop rx if packet error rate is high */
+ if (++dev->pkt_cnt > 30) {
+ dev->pkt_cnt = 0;
+ dev->pkt_err = 0;
+ } else {
+ if (state == rx_cleanup)
+ dev->pkt_err++;
+ if (dev->pkt_err > 20)
+ set_bit(EVENT_RX_KILL, &dev->flags);
+ }
+
+ state = defer_bh(dev, skb, &dev->rxq, state);
+
+ if (urb) {
+ if (netif_running (dev->net) &&
+ !test_bit (EVENT_RX_HALT, &dev->flags) &&
+ state != unlink_start) {
+ rx_submit (dev, urb, GFP_ATOMIC);
+ usb_mark_last_busy(dev->udev);
+ return;
+ }
+ usb_free_urb (urb);
+ }
+ netif_dbg(dev, rx_err, dev->net, "no read resubmitted\n");
+}
+
+/*-------------------------------------------------------------------------*/
+void usbnet_pause_rx(struct usbnet *dev)
+{
+ set_bit(EVENT_RX_PAUSED, &dev->flags);
+
+ netif_dbg(dev, rx_status, dev->net, "paused rx queue enabled\n");
+}
+EXPORT_SYMBOL_GPL(usbnet_pause_rx);
+
+void usbnet_resume_rx(struct usbnet *dev)
+{
+ struct sk_buff *skb;
+ int num = 0;
+
+ clear_bit(EVENT_RX_PAUSED, &dev->flags);
+
+ while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) {
+ usbnet_skb_return(dev, skb);
+ num++;
+ }
+
+ tasklet_schedule(&dev->bh);
+
+ netif_dbg(dev, rx_status, dev->net,
+ "paused rx queue disabled, %d skbs requeued\n", num);
+}
+EXPORT_SYMBOL_GPL(usbnet_resume_rx);
+
+void usbnet_purge_paused_rxq(struct usbnet *dev)
+{
+ skb_queue_purge(&dev->rxq_pause);
+}
+EXPORT_SYMBOL_GPL(usbnet_purge_paused_rxq);
+
+/*-------------------------------------------------------------------------*/
+
+// unlink pending rx/tx; completion handlers do all other cleanup
+
+static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q)
+{
+ unsigned long flags;
+ struct sk_buff *skb;
+ int count = 0;
+
+ spin_lock_irqsave (&q->lock, flags);
+ while (!skb_queue_empty(q)) {
+ struct skb_data *entry;
+ struct urb *urb;
+ int retval;
+
+ skb_queue_walk(q, skb) {
+ entry = (struct skb_data *) skb->cb;
+ if (entry->state != unlink_start)
+ goto found;
+ }
+ break;
+found:
+ entry->state = unlink_start;
+ urb = entry->urb;
+
+ /*
+ * Get reference count of the URB to avoid it to be
+ * freed during usb_unlink_urb, which may trigger
+ * use-after-free problem inside usb_unlink_urb since
+ * usb_unlink_urb is always racing with .complete
+ * handler(include defer_bh).
+ */
+ usb_get_urb(urb);
+ spin_unlock_irqrestore(&q->lock, flags);
+ // during some PM-driven resume scenarios,
+ // these (async) unlinks complete immediately
+ retval = usb_unlink_urb (urb);
+ if (retval != -EINPROGRESS && retval != 0)
+ netdev_dbg(dev->net, "unlink urb err, %d\n", retval);
+ else
+ count++;
+ usb_put_urb(urb);
+ spin_lock_irqsave(&q->lock, flags);
+ }
+ spin_unlock_irqrestore (&q->lock, flags);
+ return count;
+}
+
+// Flush all pending rx urbs
+// minidrivers may need to do this when the MTU changes
+
+void usbnet_unlink_rx_urbs(struct usbnet *dev)
+{
+ if (netif_running(dev->net)) {
+ (void) unlink_urbs (dev, &dev->rxq);
+ tasklet_schedule(&dev->bh);
+ }
+}
+EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
+
+/*-------------------------------------------------------------------------*/
+
+// precondition: never called in_interrupt
+static void usbnet_terminate_urbs(struct usbnet *dev)
+{
+ DECLARE_WAITQUEUE(wait, current);
+ int temp;
+
+ /* ensure there are no more active urbs */
+ add_wait_queue(&dev->wait, &wait);
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ temp = unlink_urbs(dev, &dev->txq) +
+ unlink_urbs(dev, &dev->rxq);
+
+ /* maybe wait for deletions to finish. */
+ while (!skb_queue_empty(&dev->rxq)
+ && !skb_queue_empty(&dev->txq)
+ && !skb_queue_empty(&dev->done)) {
+ schedule_timeout(msecs_to_jiffies(UNLINK_TIMEOUT_MS));
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ netif_dbg(dev, ifdown, dev->net,
+ "waited for %d urb completions\n", temp);
+ }
+ set_current_state(TASK_RUNNING);
+ remove_wait_queue(&dev->wait, &wait);
+}
+
+int usbnet_stop (struct net_device *net)
+{
+ struct usbnet *dev = netdev_priv(net);
+ struct driver_info *info = dev->driver_info;
+ int retval, pm;
+
+ clear_bit(EVENT_DEV_OPEN, &dev->flags);
+ netif_stop_queue (net);
+
+ netif_info(dev, ifdown, dev->net,
+ "stop stats: rx/tx %lu/%lu, errs %lu/%lu\n",
+ net->stats.rx_packets, net->stats.tx_packets,
+ net->stats.rx_errors, net->stats.tx_errors);
+
+ /* to not race resume */
+ pm = usb_autopm_get_interface(dev->intf);
+ /* allow minidriver to stop correctly (wireless devices to turn off
+ * radio etc) */
+ if (info->stop) {
+ retval = info->stop(dev);
+ if (retval < 0)
+ netif_info(dev, ifdown, dev->net,
+ "stop fail (%d) usbnet usb-%s-%s, %s\n",
+ retval,
+ dev->udev->bus->bus_name, dev->udev->devpath,
+ info->description);
+ }
+
+ if (!(info->flags & FLAG_AVOID_UNLINK_URBS))
+ usbnet_terminate_urbs(dev);
+
+ usbnet_status_stop(dev);
+
+ usbnet_purge_paused_rxq(dev);
+
+ /* deferred work (task, timer, softirq) must also stop.
+ * can't flush_scheduled_work() until we drop rtnl (later),
+ * else workers could deadlock; so make workers a NOP.
+ */
+ dev->flags = 0;
+ del_timer_sync (&dev->delay);
+ tasklet_kill (&dev->bh);
+ if (!pm)
+ usb_autopm_put_interface(dev->intf);
+
+ if (info->manage_power &&
+ !test_and_clear_bit(EVENT_NO_RUNTIME_PM, &dev->flags))
+ info->manage_power(dev, 0);
+ else
+ usb_autopm_put_interface(dev->intf);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(usbnet_stop);
+
+/*-------------------------------------------------------------------------*/
+
+// posts reads, and enables write queuing
+
+// precondition: never called in_interrupt
+
+int usbnet_open (struct net_device *net)
+{
+ struct usbnet *dev = netdev_priv(net);
+ int retval;
+ struct driver_info *info = dev->driver_info;
+
+ if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
+ netif_info(dev, ifup, dev->net,
+ "resumption fail (%d) usbnet usb-%s-%s, %s\n",
+ retval,
+ dev->udev->bus->bus_name,
+ dev->udev->devpath,
+ info->description);
+ goto done_nopm;
+ }
+
+ // put into "known safe" state
+ if (info->reset && (retval = info->reset (dev)) < 0) {
+ netif_info(dev, ifup, dev->net,
+ "open reset fail (%d) usbnet usb-%s-%s, %s\n",
+ retval,
+ dev->udev->bus->bus_name,
+ dev->udev->devpath,
+ info->description);
+ goto done;
+ }
+
+ /* hard_mtu or rx_urb_size may change in reset() */
+ usbnet_update_max_qlen(dev);
+
+ // insist peer be connected
+ if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
+ netif_dbg(dev, ifup, dev->net, "can't open; %d\n", retval);
+ goto done;
+ }
+
+ /* start any status interrupt transfer */
+ if (dev->interrupt) {
+ retval = usbnet_status_start(dev, GFP_KERNEL);
+ if (retval < 0) {
+ netif_err(dev, ifup, dev->net,
+ "intr submit %d\n", retval);
+ goto done;
+ }
+ }
+
+ set_bit(EVENT_DEV_OPEN, &dev->flags);
+ netif_start_queue (net);
+ netif_info(dev, ifup, dev->net,
+ "open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
+ (int)RX_QLEN(dev), (int)TX_QLEN(dev),
+ dev->net->mtu,
+ (dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
+ (dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
+ (dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
+ (dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
+ (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
+ "simple");
+
+ /* reset rx error state */
+ dev->pkt_cnt = 0;
+ dev->pkt_err = 0;
+ clear_bit(EVENT_RX_KILL, &dev->flags);
+
+ // delay posting reads until we're fully open
+ tasklet_schedule (&dev->bh);
+ if (info->manage_power) {
+ retval = info->manage_power(dev, 1);
+ if (retval < 0) {
+ retval = 0;
+ set_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
+ } else {
+ usb_autopm_put_interface(dev->intf);
+ }
+ }
+ return retval;
+done:
+ usb_autopm_put_interface(dev->intf);
+done_nopm:
+ return retval;
+}
+EXPORT_SYMBOL_GPL(usbnet_open);
+
+/*-------------------------------------------------------------------------*/
+
+/* ethtool methods; minidrivers may need to add some more, but
+ * they'll probably want to use this base set.
+ */
+
+int usbnet_get_settings (struct net_device *net, struct ethtool_cmd *cmd)
+{
+ struct usbnet *dev = netdev_priv(net);
+
+ if (!dev->mii.mdio_read)
+ return -EOPNOTSUPP;
+
+ return mii_ethtool_gset(&dev->mii, cmd);
+}
+EXPORT_SYMBOL_GPL(usbnet_get_settings);
+
+int usbnet_set_settings (struct net_device *net, struct ethtool_cmd *cmd)
+{
+ struct usbnet *dev = netdev_priv(net);
+ int retval;
+
+ if (!dev->mii.mdio_write)
+ return -EOPNOTSUPP;
+
+ retval = mii_ethtool_sset(&dev->mii, cmd);
+
+ /* link speed/duplex might have changed */
+ if (dev->driver_info->link_reset)
+ dev->driver_info->link_reset(dev);
+
+ /* hard_mtu or rx_urb_size may change in link_reset() */
+ usbnet_update_max_qlen(dev);
+
+ return retval;
+
+}
+EXPORT_SYMBOL_GPL(usbnet_set_settings);
+
+u32 usbnet_get_link (struct net_device *net)
+{
+ struct usbnet *dev = netdev_priv(net);
+
+ /* If a check_connect is defined, return its result */
+ if (dev->driver_info->check_connect)
+ return dev->driver_info->check_connect (dev) == 0;
+
+ /* if the device has mii operations, use those */
+ if (dev->mii.mdio_read)
+ return mii_link_ok(&dev->mii);
+
+ /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
+ return ethtool_op_get_link(net);
+}
+EXPORT_SYMBOL_GPL(usbnet_get_link);
+
+int usbnet_nway_reset(struct net_device *net)
+{
+ struct usbnet *dev = netdev_priv(net);
+
+ if (!dev->mii.mdio_write)
+ return -EOPNOTSUPP;
+
+ return mii_nway_restart(&dev->mii);
+}
+EXPORT_SYMBOL_GPL(usbnet_nway_reset);
+
+void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info)
+{
+ struct usbnet *dev = netdev_priv(net);
+
+ strlcpy (info->driver, dev->driver_name, sizeof info->driver);
+ strlcpy (info->version, DRIVER_VERSION, sizeof info->version);
+ strlcpy (info->fw_version, dev->driver_info->description,
+ sizeof info->fw_version);
+ usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info);
+}
+EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
+
+u32 usbnet_get_msglevel (struct net_device *net)
+{
+ struct usbnet *dev = netdev_priv(net);
+
+ return dev->msg_enable;
+}
+EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
+
+void usbnet_set_msglevel (struct net_device *net, u32 level)
+{
+ struct usbnet *dev = netdev_priv(net);
+
+ dev->msg_enable = level;
+}
+EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
+
+/* drivers may override default ethtool_ops in their bind() routine */
+static const struct ethtool_ops usbnet_ethtool_ops = {
+ .get_settings = usbnet_get_settings,
+ .set_settings = usbnet_set_settings,
+ .get_link = usbnet_get_link,
+ .nway_reset = usbnet_nway_reset,
+ .get_drvinfo = usbnet_get_drvinfo,
+ .get_msglevel = usbnet_get_msglevel,
+ .set_msglevel = usbnet_set_msglevel,
+ .get_ts_info = ethtool_op_get_ts_info,
+};
+
+/*-------------------------------------------------------------------------*/
+
+static void __handle_link_change(struct usbnet *dev)
+{
+ if (!test_bit(EVENT_DEV_OPEN, &dev->flags))
+ return;
+
+ if (!netif_carrier_ok(dev->net)) {
+ /* kill URBs for reading packets to save bus bandwidth */
+ unlink_urbs(dev, &dev->rxq);
+
+ /*
+ * tx_timeout will unlink URBs for sending packets and
+ * tx queue is stopped by netcore after link becomes off
+ */
+ } else {
+ /* submitting URBs for reading packets */
+ tasklet_schedule(&dev->bh);
+ }
+
+ /* hard_mtu or rx_urb_size may change during link change */
+ usbnet_update_max_qlen(dev);
+
+ clear_bit(EVENT_LINK_CHANGE, &dev->flags);
+}
+
+static void usbnet_set_rx_mode(struct net_device *net)
+{
+ struct usbnet *dev = netdev_priv(net);
+
+ usbnet_defer_kevent(dev, EVENT_SET_RX_MODE);
+}
+
+static void __handle_set_rx_mode(struct usbnet *dev)
+{
+ if (dev->driver_info->set_rx_mode)
+ (dev->driver_info->set_rx_mode)(dev);
+
+ clear_bit(EVENT_SET_RX_MODE, &dev->flags);
+}
+
+/* work that cannot be done in interrupt context uses keventd.
+ *
+ * NOTE: with 2.5 we could do more of this using completion callbacks,
+ * especially now that control transfers can be queued.
+ */
+static void
+usbnet_deferred_kevent (struct work_struct *work)
+{
+ struct usbnet *dev =
+ container_of(work, struct usbnet, kevent);
+ int status;
+
+ /* usb_clear_halt() needs a thread context */
+ if (test_bit (EVENT_TX_HALT, &dev->flags)) {
+ unlink_urbs (dev, &dev->txq);
+ status = usb_autopm_get_interface(dev->intf);
+ if (status < 0)
+ goto fail_pipe;
+ status = usb_clear_halt (dev->udev, dev->out);
+ usb_autopm_put_interface(dev->intf);
+ if (status < 0 &&
+ status != -EPIPE &&
+ status != -ESHUTDOWN) {
+ if (netif_msg_tx_err (dev))
+fail_pipe:
+ netdev_err(dev->net, "can't clear tx halt, status %d\n",
+ status);
+ } else {
+ clear_bit (EVENT_TX_HALT, &dev->flags);
+ if (status != -ESHUTDOWN)
+ netif_wake_queue (dev->net);
+ }
+ }
+ if (test_bit (EVENT_RX_HALT, &dev->flags)) {
+ unlink_urbs (dev, &dev->rxq);
+ status = usb_autopm_get_interface(dev->intf);
+ if (status < 0)
+ goto fail_halt;
+ status = usb_clear_halt (dev->udev, dev->in);
+ usb_autopm_put_interface(dev->intf);
+ if (status < 0 &&
+ status != -EPIPE &&
+ status != -ESHUTDOWN) {
+ if (netif_msg_rx_err (dev))
+fail_halt:
+ netdev_err(dev->net, "can't clear rx halt, status %d\n",
+ status);
+ } else {
+ clear_bit (EVENT_RX_HALT, &dev->flags);
+ tasklet_schedule (&dev->bh);
+ }
+ }
+
+ /* tasklet could resubmit itself forever if memory is tight */
+ if (test_bit (EVENT_RX_MEMORY, &dev->flags)) {
+ struct urb *urb = NULL;
+ int resched = 1;
+
+ if (netif_running (dev->net))
+ urb = usb_alloc_urb (0, GFP_KERNEL);
+ else
+ clear_bit (EVENT_RX_MEMORY, &dev->flags);
+ if (urb != NULL) {
+ clear_bit (EVENT_RX_MEMORY, &dev->flags);
+ status = usb_autopm_get_interface(dev->intf);
+ if (status < 0) {
+ usb_free_urb(urb);
+ goto fail_lowmem;
+ }
+ if (rx_submit (dev, urb, GFP_KERNEL) == -ENOLINK)
+ resched = 0;
+ usb_autopm_put_interface(dev->intf);
+fail_lowmem:
+ if (resched)
+ tasklet_schedule (&dev->bh);
+ }
+ }
+
+ if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
+ struct driver_info *info = dev->driver_info;
+ int retval = 0;
+
+ clear_bit (EVENT_LINK_RESET, &dev->flags);
+ status = usb_autopm_get_interface(dev->intf);
+ if (status < 0)
+ goto skip_reset;
+ if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
+ usb_autopm_put_interface(dev->intf);
+skip_reset:
+ netdev_info(dev->net, "link reset failed (%d) usbnet usb-%s-%s, %s\n",
+ retval,
+ dev->udev->bus->bus_name,
+ dev->udev->devpath,
+ info->description);
+ } else {
+ usb_autopm_put_interface(dev->intf);
+ }
+
+ /* handle link change from link resetting */
+ __handle_link_change(dev);
+ }
+
+ if (test_bit (EVENT_LINK_CHANGE, &dev->flags))
+ __handle_link_change(dev);
+
+ if (test_bit (EVENT_SET_RX_MODE, &dev->flags))
+ __handle_set_rx_mode(dev);
+
+
+ if (dev->flags)
+ netdev_dbg(dev->net, "kevent done, flags = 0x%lx\n", dev->flags);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void tx_complete (struct urb *urb)
+{
+ struct sk_buff *skb = (struct sk_buff *) urb->context;
+ struct skb_data *entry = (struct skb_data *) skb->cb;
+ struct usbnet *dev = entry->dev;
+
+ if (urb->status == 0) {
+ dev->net->stats.tx_packets += entry->packets;
+ dev->net->stats.tx_bytes += entry->length;
+ } else {
+ dev->net->stats.tx_errors++;
+
+ switch (urb->status) {
+ case -EPIPE:
+ usbnet_defer_kevent (dev, EVENT_TX_HALT);
+ break;
+
+ /* software-driven interface shutdown */
+ case -ECONNRESET: // async unlink
+ case -ESHUTDOWN: // hardware gone
+ break;
+
+ /* like rx, tx gets controller i/o faults during hub_wq
+ * delays and so it uses the same throttling mechanism.
+ */
+ case -EPROTO:
+ case -ETIME:
+ case -EILSEQ:
+ usb_mark_last_busy(dev->udev);
+ if (!timer_pending (&dev->delay)) {
+ mod_timer (&dev->delay,
+ jiffies + THROTTLE_JIFFIES);
+ netif_dbg(dev, link, dev->net,
+ "tx throttle %d\n", urb->status);
+ }
+ netif_stop_queue (dev->net);
+ break;
+ default:
+ netif_dbg(dev, tx_err, dev->net,
+ "tx err %d\n", entry->urb->status);
+ break;
+ }
+ }
+
+ usb_autopm_put_interface_async(dev->intf);
+ (void) defer_bh(dev, skb, &dev->txq, tx_done);
+}
+
+/*-------------------------------------------------------------------------*/
+
+void usbnet_tx_timeout (struct net_device *net)
+{
+ struct usbnet *dev = netdev_priv(net);
+
+ unlink_urbs (dev, &dev->txq);
+ tasklet_schedule (&dev->bh);
+ /* this needs to be handled individually because the generic layer
+ * doesn't know what is sufficient and could not restore private
+ * information if a remedy of an unconditional reset were used.
+ */
+ if (dev->driver_info->recover)
+ (dev->driver_info->recover)(dev);
+}
+EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
+
+/*-------------------------------------------------------------------------*/
+
+static int build_dma_sg(const struct sk_buff *skb, struct urb *urb)
+{
+ unsigned num_sgs, total_len = 0;
+ int i, s = 0;
+
+ num_sgs = skb_shinfo(skb)->nr_frags + 1;
+ if (num_sgs == 1)
+ return 0;
+
+ /* reserve one for zero packet */
+ urb->sg = kmalloc((num_sgs + 1) * sizeof(struct scatterlist),
+ GFP_ATOMIC);
+ if (!urb->sg)
+ return -ENOMEM;
+
+ urb->num_sgs = num_sgs;
+ sg_init_table(urb->sg, urb->num_sgs + 1);
+
+ sg_set_buf(&urb->sg[s++], skb->data, skb_headlen(skb));
+ total_len += skb_headlen(skb);
+
+ for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+ struct skb_frag_struct *f = &skb_shinfo(skb)->frags[i];
+
+ total_len += skb_frag_size(f);
+ sg_set_page(&urb->sg[i + s], f->page.p, f->size,
+ f->page_offset);
+ }
+ urb->transfer_buffer_length = total_len;
+
+ return 1;
+}
+
+netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
+ struct net_device *net)
+{
+ struct usbnet *dev = netdev_priv(net);
+ unsigned int length;
+ struct urb *urb = NULL;
+ struct skb_data *entry;
+ struct driver_info *info = dev->driver_info;
+ unsigned long flags;
+ int retval;
+
+ if (skb)
+ skb_tx_timestamp(skb);
+
+ // some devices want funky USB-level framing, for
+ // win32 driver (usually) and/or hardware quirks
+ if (info->tx_fixup) {
+ skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
+ if (!skb) {
+ /* packet collected; minidriver waiting for more */
+ if (info->flags & FLAG_MULTI_PACKET)
+ goto not_drop;
+ netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
+ goto drop;
+ }
+ }
+
+ if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
+ netif_dbg(dev, tx_err, dev->net, "no urb\n");
+ goto drop;
+ }
+
+ entry = (struct skb_data *) skb->cb;
+ entry->urb = urb;
+ entry->dev = dev;
+
+ usb_fill_bulk_urb (urb, dev->udev, dev->out,
+ skb->data, skb->len, tx_complete, skb);
+ if (dev->can_dma_sg) {
+ if (build_dma_sg(skb, urb) < 0)
+ goto drop;
+ }
+ length = urb->transfer_buffer_length;
+
+ /* don't assume the hardware handles USB_ZERO_PACKET
+ * NOTE: strictly conforming cdc-ether devices should expect
+ * the ZLP here, but ignore the one-byte packet.
+ * NOTE2: CDC NCM specification is different from CDC ECM when
+ * handling ZLP/short packets, so cdc_ncm driver will make short
+ * packet itself if needed.
+ */
+ if (length % dev->maxpacket == 0) {
+ if (!(info->flags & FLAG_SEND_ZLP)) {
+ if (!(info->flags & FLAG_MULTI_PACKET)) {
+ length++;
+ if (skb_tailroom(skb) && !urb->num_sgs) {
+ skb->data[skb->len] = 0;
+ __skb_put(skb, 1);
+ } else if (urb->num_sgs)
+ sg_set_buf(&urb->sg[urb->num_sgs++],
+ dev->padding_pkt, 1);
+ }
+ } else
+ urb->transfer_flags |= URB_ZERO_PACKET;
+ }
+ urb->transfer_buffer_length = length;
+
+ if (info->flags & FLAG_MULTI_PACKET) {
+ /* Driver has set number of packets and a length delta.
+ * Calculate the complete length and ensure that it's
+ * positive.
+ */
+ entry->length += length;
+ if (WARN_ON_ONCE(entry->length <= 0))
+ entry->length = length;
+ } else {
+ usbnet_set_skb_tx_stats(skb, 1, length);
+ }
+
+ spin_lock_irqsave(&dev->txq.lock, flags);
+ retval = usb_autopm_get_interface_async(dev->intf);
+ if (retval < 0) {
+ spin_unlock_irqrestore(&dev->txq.lock, flags);
+ goto drop;
+ }
+
+#ifdef CONFIG_PM
+ /* if this triggers the device is still a sleep */
+ if (test_bit(EVENT_DEV_ASLEEP, &dev->flags)) {
+ /* transmission will be done in resume */
+ usb_anchor_urb(urb, &dev->deferred);
+ /* no use to process more packets */
+ netif_stop_queue(net);
+ usb_put_urb(urb);
+ spin_unlock_irqrestore(&dev->txq.lock, flags);
+ netdev_dbg(dev->net, "Delaying transmission for resumption\n");
+ goto deferred;
+ }
+#endif
+
+ switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
+ case -EPIPE:
+ netif_stop_queue (net);
+ usbnet_defer_kevent (dev, EVENT_TX_HALT);
+ usb_autopm_put_interface_async(dev->intf);
+ break;
+ default:
+ usb_autopm_put_interface_async(dev->intf);
+ netif_dbg(dev, tx_err, dev->net,
+ "tx: submit urb err %d\n", retval);
+ break;
+ case 0:
+ net->trans_start = jiffies;
+ __usbnet_queue_skb(&dev->txq, skb, tx_start);
+ if (dev->txq.qlen >= TX_QLEN (dev))
+ netif_stop_queue (net);
+ }
+ spin_unlock_irqrestore (&dev->txq.lock, flags);
+
+ if (retval) {
+ netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
+drop:
+ dev->net->stats.tx_dropped++;
+not_drop:
+ if (skb)
+ dev_kfree_skb_any (skb);
+ if (urb) {
+ kfree(urb->sg);
+ usb_free_urb(urb);
+ }
+ } else
+ netif_dbg(dev, tx_queued, dev->net,
+ "> tx, len %u, type 0x%x\n", length, skb->protocol);
+#ifdef CONFIG_PM
+deferred:
+#endif
+ return NETDEV_TX_OK;
+}
+EXPORT_SYMBOL_GPL(usbnet_start_xmit);
+
+static int rx_alloc_submit(struct usbnet *dev, gfp_t flags)
+{
+ struct urb *urb;
+ int i;
+ int ret = 0;
+
+ /* don't refill the queue all at once */
+ for (i = 0; i < 10 && dev->rxq.qlen < RX_QLEN(dev); i++) {
+ urb = usb_alloc_urb(0, flags);
+ if (urb != NULL) {
+ ret = rx_submit(dev, urb, flags);
+ if (ret)
+ goto err;
+ } else {
+ ret = -ENOMEM;
+ goto err;
+ }
+ }
+err:
+ return ret;
+}
+
+/*-------------------------------------------------------------------------*/
+
+// tasklet (work deferred from completions, in_irq) or timer
+
+static void usbnet_bh (unsigned long param)
+{
+ struct usbnet *dev = (struct usbnet *) param;
+ struct sk_buff *skb;
+ struct skb_data *entry;
+
+ while ((skb = skb_dequeue (&dev->done))) {
+ entry = (struct skb_data *) skb->cb;
+ switch (entry->state) {
+ case rx_done:
+ entry->state = rx_cleanup;
+ rx_process (dev, skb);
+ continue;
+ case tx_done:
+ kfree(entry->urb->sg);
+ case rx_cleanup:
+ usb_free_urb (entry->urb);
+ dev_kfree_skb (skb);
+ continue;
+ default:
+ netdev_dbg(dev->net, "bogus skb state %d\n", entry->state);
+ }
+ }
+
+ /* restart RX again after disabling due to high error rate */
+ clear_bit(EVENT_RX_KILL, &dev->flags);
+
+ /* waiting for all pending urbs to complete?
+ * only then can we forgo submitting anew
+ */
+ if (waitqueue_active(&dev->wait)) {
+ if (dev->txq.qlen + dev->rxq.qlen + dev->done.qlen == 0)
+ wake_up_all(&dev->wait);
+
+ // or are we maybe short a few urbs?
+ } else if (netif_running (dev->net) &&
+ netif_device_present (dev->net) &&
+ netif_carrier_ok(dev->net) &&
+ !timer_pending (&dev->delay) &&
+ !test_bit (EVENT_RX_HALT, &dev->flags)) {
+ int temp = dev->rxq.qlen;
+
+ if (temp < RX_QLEN(dev)) {
+ if (rx_alloc_submit(dev, GFP_ATOMIC) == -ENOLINK)
+ return;
+ if (temp != dev->rxq.qlen)
+ netif_dbg(dev, link, dev->net,
+ "rxqlen %d --> %d\n",
+ temp, dev->rxq.qlen);
+ if (dev->rxq.qlen < RX_QLEN(dev))
+ tasklet_schedule (&dev->bh);
+ }
+ if (dev->txq.qlen < TX_QLEN (dev))
+ netif_wake_queue (dev->net);
+ }
+}
+
+
+/*-------------------------------------------------------------------------
+ *
+ * USB Device Driver support
+ *
+ *-------------------------------------------------------------------------*/
+
+// precondition: never called in_interrupt
+
+void usbnet_disconnect (struct usb_interface *intf)
+{
+ struct usbnet *dev;
+ struct usb_device *xdev;
+ struct net_device *net;
+
+ dev = usb_get_intfdata(intf);
+ usb_set_intfdata(intf, NULL);
+ if (!dev)
+ return;
+
+ xdev = interface_to_usbdev (intf);
+
+ netif_info(dev, probe, dev->net, "unregister '%s' usb-%s-%s, %s\n",
+ intf->dev.driver->name,
+ xdev->bus->bus_name, xdev->devpath,
+ dev->driver_info->description);
+
+ net = dev->net;
+ unregister_netdev (net);
+
+ cancel_work_sync(&dev->kevent);
+
+ usb_scuttle_anchored_urbs(&dev->deferred);
+
+ if (dev->driver_info->unbind)
+ dev->driver_info->unbind (dev, intf);
+
+ usb_kill_urb(dev->interrupt);
+ usb_free_urb(dev->interrupt);
+ kfree(dev->padding_pkt);
+
+ free_netdev(net);
+}
+EXPORT_SYMBOL_GPL(usbnet_disconnect);
+
+static const struct net_device_ops usbnet_netdev_ops = {
+ .ndo_open = usbnet_open,
+ .ndo_stop = usbnet_stop,
+ .ndo_start_xmit = usbnet_start_xmit,
+ .ndo_tx_timeout = usbnet_tx_timeout,
+ .ndo_set_rx_mode = usbnet_set_rx_mode,
+ .ndo_change_mtu = usbnet_change_mtu,
+ .ndo_set_mac_address = eth_mac_addr,
+ .ndo_validate_addr = eth_validate_addr,
+};
+
+/*-------------------------------------------------------------------------*/
+
+// precondition: never called in_interrupt
+
+static struct device_type wlan_type = {
+ .name = "wlan",
+};
+
+static struct device_type wwan_type = {
+ .name = "wwan",
+};
+
+int
+usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
+{
+ struct usbnet *dev;
+ struct net_device *net;
+ struct usb_host_interface *interface;
+ struct driver_info *info;
+ struct usb_device *xdev;
+ int status;
+ const char *name;
+ struct usb_driver *driver = to_usb_driver(udev->dev.driver);
+
+ /* usbnet already took usb runtime pm, so have to enable the feature
+ * for usb interface, otherwise usb_autopm_get_interface may return
+ * failure if RUNTIME_PM is enabled.
+ */
+ if (!driver->supports_autosuspend) {
+ driver->supports_autosuspend = 1;
+ pm_runtime_enable(&udev->dev);
+ }
+
+ name = udev->dev.driver->name;
+ info = (struct driver_info *) prod->driver_info;
+ if (!info) {
+ dev_dbg (&udev->dev, "blacklisted by %s\n", name);
+ return -ENODEV;
+ }
+ xdev = interface_to_usbdev (udev);
+ interface = udev->cur_altsetting;
+
+ status = -ENOMEM;
+
+ // set up our own records
+ net = alloc_etherdev(sizeof(*dev));
+ if (!net)
+ goto out;
+
+ /* netdev_printk() needs this so do it as early as possible */
+ SET_NETDEV_DEV(net, &udev->dev);
+
+ dev = netdev_priv(net);
+ dev->udev = xdev;
+ dev->intf = udev;
+ dev->driver_info = info;
+ dev->driver_name = name;
+ dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
+ | NETIF_MSG_PROBE | NETIF_MSG_LINK);
+ init_waitqueue_head(&dev->wait);
+ skb_queue_head_init (&dev->rxq);
+ skb_queue_head_init (&dev->txq);
+ skb_queue_head_init (&dev->done);
+ skb_queue_head_init(&dev->rxq_pause);
+ dev->bh.func = usbnet_bh;
+ dev->bh.data = (unsigned long) dev;
+ INIT_WORK (&dev->kevent, usbnet_deferred_kevent);
+ init_usb_anchor(&dev->deferred);
+ dev->delay.function = usbnet_bh;
+ dev->delay.data = (unsigned long) dev;
+ init_timer (&dev->delay);
+ mutex_init (&dev->phy_mutex);
+ mutex_init(&dev->interrupt_mutex);
+ dev->interrupt_count = 0;
+
+ dev->net = net;
+ strcpy (net->name, "usb%d");
+ memcpy (net->dev_addr, node_id, sizeof node_id);
+
+ /* rx and tx sides can use different message sizes;
+ * bind() should set rx_urb_size in that case.
+ */
+ dev->hard_mtu = net->mtu + net->hard_header_len;
+#if 0
+// dma_supported() is deeply broken on almost all architectures
+ // possible with some EHCI controllers
+ if (dma_supported (&udev->dev, DMA_BIT_MASK(64)))
+ net->features |= NETIF_F_HIGHDMA;
+#endif
+
+ net->netdev_ops = &usbnet_netdev_ops;
+ net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
+ net->ethtool_ops = &usbnet_ethtool_ops;
+
+ // allow device-specific bind/init procedures
+ // NOTE net->name still not usable ...
+ if (info->bind) {
+ status = info->bind (dev, udev);
+ if (status < 0)
+ goto out1;
+
+ // heuristic: "usb%d" for links we know are two-host,
+ // else "eth%d" when there's reasonable doubt. userspace
+ // can rename the link if it knows better.
+ if ((dev->driver_info->flags & FLAG_ETHER) != 0 &&
+ ((dev->driver_info->flags & FLAG_POINTTOPOINT) == 0 ||
+ (net->dev_addr [0] & 0x02) == 0))
+ strcpy (net->name, "eth%d");
+ /* WLAN devices should always be named "wlan%d" */
+ if ((dev->driver_info->flags & FLAG_WLAN) != 0)
+ strcpy(net->name, "wlan%d");
+ /* WWAN devices should always be named "wwan%d" */
+ if ((dev->driver_info->flags & FLAG_WWAN) != 0)
+ strcpy(net->name, "wwan%d");
+
+ /* devices that cannot do ARP */
+ if ((dev->driver_info->flags & FLAG_NOARP) != 0)
+ net->flags |= IFF_NOARP;
+
+ /* maybe the remote can't receive an Ethernet MTU */
+ if (net->mtu > (dev->hard_mtu - net->hard_header_len))
+ net->mtu = dev->hard_mtu - net->hard_header_len;
+ } else if (!info->in || !info->out)
+ status = usbnet_get_endpoints (dev, udev);
+ else {
+ dev->in = usb_rcvbulkpipe (xdev, info->in);
+ dev->out = usb_sndbulkpipe (xdev, info->out);
+ if (!(info->flags & FLAG_NO_SETINT))
+ status = usb_set_interface (xdev,
+ interface->desc.bInterfaceNumber,
+ interface->desc.bAlternateSetting);
+ else
+ status = 0;
+
+ }
+ if (status >= 0 && dev->status)
+ status = init_status (dev, udev);
+ if (status < 0)
+ goto out3;
+
+ if (!dev->rx_urb_size)
+ dev->rx_urb_size = dev->hard_mtu;
+ dev->maxpacket = usb_maxpacket (dev->udev, dev->out, 1);
+
+ /* let userspace know we have a random address */
+ if (ether_addr_equal(net->dev_addr, node_id))
+ net->addr_assign_type = NET_ADDR_RANDOM;
+
+ if ((dev->driver_info->flags & FLAG_WLAN) != 0)
+ SET_NETDEV_DEVTYPE(net, &wlan_type);
+ if ((dev->driver_info->flags & FLAG_WWAN) != 0)
+ SET_NETDEV_DEVTYPE(net, &wwan_type);
+
+ /* initialize max rx_qlen and tx_qlen */
+ usbnet_update_max_qlen(dev);
+
+ if (dev->can_dma_sg && !(info->flags & FLAG_SEND_ZLP) &&
+ !(info->flags & FLAG_MULTI_PACKET)) {
+ dev->padding_pkt = kzalloc(1, GFP_KERNEL);
+ if (!dev->padding_pkt) {
+ status = -ENOMEM;
+ goto out4;
+ }
+ }
+
+ status = register_netdev (net);
+ if (status)
+ goto out5;
+ netif_info(dev, probe, dev->net,
+ "register '%s' at usb-%s-%s, %s, %pM\n",
+ udev->dev.driver->name,
+ xdev->bus->bus_name, xdev->devpath,
+ dev->driver_info->description,
+ net->dev_addr);
+
+ // ok, it's ready to go.
+ usb_set_intfdata (udev, dev);
+
+ netif_device_attach (net);
+
+ if (dev->driver_info->flags & FLAG_LINK_INTR)
+ usbnet_link_change(dev, 0, 0);
+
+ return 0;
+
+out5:
+ kfree(dev->padding_pkt);
+out4:
+ usb_free_urb(dev->interrupt);
+out3:
+ if (info->unbind)
+ info->unbind (dev, udev);
+out1:
+ free_netdev(net);
+out:
+ return status;
+}
+EXPORT_SYMBOL_GPL(usbnet_probe);
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * suspend the whole driver as soon as the first interface is suspended
+ * resume only when the last interface is resumed
+ */
+
+int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
+{
+ struct usbnet *dev = usb_get_intfdata(intf);
+
+ if (!dev->suspend_count++) {
+ spin_lock_irq(&dev->txq.lock);
+ /* don't autosuspend while transmitting */
+ if (dev->txq.qlen && PMSG_IS_AUTO(message)) {
+ dev->suspend_count--;
+ spin_unlock_irq(&dev->txq.lock);
+ return -EBUSY;
+ } else {
+ set_bit(EVENT_DEV_ASLEEP, &dev->flags);
+ spin_unlock_irq(&dev->txq.lock);
+ }
+ /*
+ * accelerate emptying of the rx and queues, to avoid
+ * having everything error out.
+ */
+ netif_device_detach (dev->net);
+ usbnet_terminate_urbs(dev);
+ __usbnet_status_stop_force(dev);
+
+ /*
+ * reattach so runtime management can use and
+ * wake the device
+ */
+ netif_device_attach (dev->net);
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(usbnet_suspend);
+
+int usbnet_resume (struct usb_interface *intf)
+{
+ struct usbnet *dev = usb_get_intfdata(intf);
+ struct sk_buff *skb;
+ struct urb *res;
+ int retval;
+
+ if (!--dev->suspend_count) {
+ /* resume interrupt URB if it was previously submitted */
+ __usbnet_status_start_force(dev, GFP_NOIO);
+
+ spin_lock_irq(&dev->txq.lock);
+ while ((res = usb_get_from_anchor(&dev->deferred))) {
+
+ skb = (struct sk_buff *)res->context;
+ retval = usb_submit_urb(res, GFP_ATOMIC);
+ if (retval < 0) {
+ dev_kfree_skb_any(skb);
+ kfree(res->sg);
+ usb_free_urb(res);
+ usb_autopm_put_interface_async(dev->intf);
+ } else {
+ dev->net->trans_start = jiffies;
+ __skb_queue_tail(&dev->txq, skb);
+ }
+ }
+
+ smp_mb();
+ clear_bit(EVENT_DEV_ASLEEP, &dev->flags);
+ spin_unlock_irq(&dev->txq.lock);
+
+ if (test_bit(EVENT_DEV_OPEN, &dev->flags)) {
+ /* handle remote wakeup ASAP
+ * we cannot race against stop
+ */
+ if (netif_device_present(dev->net) &&
+ !timer_pending(&dev->delay) &&
+ !test_bit(EVENT_RX_HALT, &dev->flags))
+ rx_alloc_submit(dev, GFP_NOIO);
+
+ if (!(dev->txq.qlen >= TX_QLEN(dev)))
+ netif_tx_wake_all_queues(dev->net);
+ tasklet_schedule (&dev->bh);
+ }
+ }
+
+ if (test_and_clear_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags))
+ usb_autopm_get_interface_no_resume(intf);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(usbnet_resume);
+
+/*
+ * Either a subdriver implements manage_power, then it is assumed to always
+ * be ready to be suspended or it reports the readiness to be suspended
+ * explicitly
+ */
+void usbnet_device_suggests_idle(struct usbnet *dev)
+{
+ if (!test_and_set_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags)) {
+ dev->intf->needs_remote_wakeup = 1;
+ usb_autopm_put_interface_async(dev->intf);
+ }
+}
+EXPORT_SYMBOL(usbnet_device_suggests_idle);
+
+/*
+ * For devices that can do without special commands
+ */
+int usbnet_manage_power(struct usbnet *dev, int on)
+{
+ dev->intf->needs_remote_wakeup = on;
+ return 0;
+}
+EXPORT_SYMBOL(usbnet_manage_power);
+
+void usbnet_link_change(struct usbnet *dev, bool link, bool need_reset)
+{
+ /* update link after link is reseted */
+ if (link && !need_reset)
+ netif_carrier_on(dev->net);
+ else
+ netif_carrier_off(dev->net);
+
+ if (need_reset && link)
+ usbnet_defer_kevent(dev, EVENT_LINK_RESET);
+ else
+ usbnet_defer_kevent(dev, EVENT_LINK_CHANGE);
+}
+EXPORT_SYMBOL(usbnet_link_change);
+
+/*-------------------------------------------------------------------------*/
+static int __usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
+ u16 value, u16 index, void *data, u16 size)
+{
+ void *buf = NULL;
+ int err = -ENOMEM;
+
+ netdev_dbg(dev->net, "usbnet_read_cmd cmd=0x%02x reqtype=%02x"
+ " value=0x%04x index=0x%04x size=%d\n",
+ cmd, reqtype, value, index, size);
+
+ if (data) {
+ buf = kmalloc(size, GFP_KERNEL);
+ if (!buf)
+ goto out;
+ }
+
+ err = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
+ cmd, reqtype, value, index, buf, size,
+ USB_CTRL_GET_TIMEOUT);
+ if (err > 0 && err <= size)
+ memcpy(data, buf, err);
+ kfree(buf);
+out:
+ return err;
+}
+
+static int __usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
+ u16 value, u16 index, const void *data,
+ u16 size)
+{
+ void *buf = NULL;
+ int err = -ENOMEM;
+
+ netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
+ " value=0x%04x index=0x%04x size=%d\n",
+ cmd, reqtype, value, index, size);
+
+ if (data) {
+ buf = kmemdup(data, size, GFP_KERNEL);
+ if (!buf)
+ goto out;
+ }
+
+ err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
+ cmd, reqtype, value, index, buf, size,
+ USB_CTRL_SET_TIMEOUT);
+ kfree(buf);
+
+out:
+ return err;
+}
+
+/*
+ * The function can't be called inside suspend/resume callback,
+ * otherwise deadlock will be caused.
+ */
+int usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
+ u16 value, u16 index, void *data, u16 size)
+{
+ int ret;
+
+ if (usb_autopm_get_interface(dev->intf) < 0)
+ return -ENODEV;
+ ret = __usbnet_read_cmd(dev, cmd, reqtype, value, index,
+ data, size);
+ usb_autopm_put_interface(dev->intf);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(usbnet_read_cmd);
+
+/*
+ * The function can't be called inside suspend/resume callback,
+ * otherwise deadlock will be caused.
+ */
+int usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
+ u16 value, u16 index, const void *data, u16 size)
+{
+ int ret;
+
+ if (usb_autopm_get_interface(dev->intf) < 0)
+ return -ENODEV;
+ ret = __usbnet_write_cmd(dev, cmd, reqtype, value, index,
+ data, size);
+ usb_autopm_put_interface(dev->intf);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(usbnet_write_cmd);
+
+/*
+ * The function can be called inside suspend/resume callback safely
+ * and should only be called by suspend/resume callback generally.
+ */
+int usbnet_read_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
+ u16 value, u16 index, void *data, u16 size)
+{
+ return __usbnet_read_cmd(dev, cmd, reqtype, value, index,
+ data, size);
+}
+EXPORT_SYMBOL_GPL(usbnet_read_cmd_nopm);
+
+/*
+ * The function can be called inside suspend/resume callback safely
+ * and should only be called by suspend/resume callback generally.
+ */
+int usbnet_write_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
+ u16 value, u16 index, const void *data,
+ u16 size)
+{
+ return __usbnet_write_cmd(dev, cmd, reqtype, value, index,
+ data, size);
+}
+EXPORT_SYMBOL_GPL(usbnet_write_cmd_nopm);
+
+static void usbnet_async_cmd_cb(struct urb *urb)
+{
+ struct usb_ctrlrequest *req = (struct usb_ctrlrequest *)urb->context;
+ int status = urb->status;
+
+ if (status < 0)
+ dev_dbg(&urb->dev->dev, "%s failed with %d",
+ __func__, status);
+
+ kfree(req);
+ usb_free_urb(urb);
+}
+
+/*
+ * The caller must make sure that device can't be put into suspend
+ * state until the control URB completes.
+ */
+int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype,
+ u16 value, u16 index, const void *data, u16 size)
+{
+ struct usb_ctrlrequest *req = NULL;
+ struct urb *urb;
+ int err = -ENOMEM;
+ void *buf = NULL;
+
+ netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
+ " value=0x%04x index=0x%04x size=%d\n",
+ cmd, reqtype, value, index, size);
+
+ urb = usb_alloc_urb(0, GFP_ATOMIC);
+ if (!urb) {
+ netdev_err(dev->net, "Error allocating URB in"
+ " %s!\n", __func__);
+ goto fail;
+ }
+
+ if (data) {
+ buf = kmemdup(data, size, GFP_ATOMIC);
+ if (!buf) {
+ netdev_err(dev->net, "Error allocating buffer"
+ " in %s!\n", __func__);
+ goto fail_free;
+ }
+ }
+
+ req = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
+ if (!req)
+ goto fail_free_buf;
+
+ req->bRequestType = reqtype;
+ req->bRequest = cmd;
+ req->wValue = cpu_to_le16(value);
+ req->wIndex = cpu_to_le16(index);
+ req->wLength = cpu_to_le16(size);
+
+ usb_fill_control_urb(urb, dev->udev,
+ usb_sndctrlpipe(dev->udev, 0),
+ (void *)req, buf, size,
+ usbnet_async_cmd_cb, req);
+ urb->transfer_flags |= URB_FREE_BUFFER;
+
+ err = usb_submit_urb(urb, GFP_ATOMIC);
+ if (err < 0) {
+ netdev_err(dev->net, "Error submitting the control"
+ " message: status=%d\n", err);
+ goto fail_free;
+ }
+ return 0;
+
+fail_free_buf:
+ kfree(buf);
+fail_free:
+ kfree(req);
+ usb_free_urb(urb);
+fail:
+ return err;
+
+}
+EXPORT_SYMBOL_GPL(usbnet_write_cmd_async);
+/*-------------------------------------------------------------------------*/
+
+static int __init usbnet_init(void)
+{
+ /* Compiler should optimize this out. */
+ BUILD_BUG_ON(
+ FIELD_SIZEOF(struct sk_buff, cb) < sizeof(struct skb_data));
+
+ eth_random_addr(node_id);
+ return 0;
+}
+module_init(usbnet_init);
+
+static void __exit usbnet_exit(void)
+{
+}
+module_exit(usbnet_exit);
+
+MODULE_AUTHOR("David Brownell");
+MODULE_DESCRIPTION("USB network driver framework");
+MODULE_LICENSE("GPL");