2 * u_ether.c -- Ethernet-over-USB link layer utilities for Gadget stack
4 * Copyright (C) 2003-2005,2008 David Brownell
5 * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
6 * Copyright (C) 2008 Nokia Corporation
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
14 /* #define VERBOSE_DEBUG */
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/gfp.h>
19 #include <linux/device.h>
20 #include <linux/ctype.h>
21 #include <linux/etherdevice.h>
22 #include <linux/ethtool.h>
28 * This component encapsulates the Ethernet link glue needed to provide
29 * one (!) network link through the USB gadget stack, normally "usb0".
31 * The control and data models are handled by the function driver which
32 * connects to this code; such as CDC Ethernet (ECM or EEM),
33 * "CDC Subset", or RNDIS. That includes all descriptor and endpoint
36 * Link level addressing is handled by this component using module
37 * parameters; if no such parameters are provided, random link level
38 * addresses are used. Each end of the link uses one address. The
39 * host end address is exported in various ways, and is often recorded
40 * in configuration databases.
42 * The driver which assembles each configuration using such a link is
43 * responsible for ensuring that each configuration includes at most one
44 * instance of is network link. (The network layer provides ways for
45 * this single "physical" link to be used by multiple virtual links.)
48 #define UETH__VERSION "29-May-2008"
51 /* lock is held while accessing port_usb
52 * or updating its backlink port_usb->ioport
55 struct gether *port_usb;
57 struct net_device *net;
58 struct usb_gadget *gadget;
60 spinlock_t req_lock; /* guard {rx,tx}_reqs */
61 struct list_head tx_reqs, rx_reqs;
64 struct sk_buff_head rx_frames;
67 struct sk_buff *(*wrap)(struct gether *, struct sk_buff *skb);
68 int (*unwrap)(struct gether *,
70 struct sk_buff_head *list);
72 struct work_struct work;
75 #define WORK_RX_MEMORY 0
78 u8 host_mac[ETH_ALEN];
81 /*-------------------------------------------------------------------------*/
83 #define RX_EXTRA 20 /* bytes guarding against rx overflows */
85 #define DEFAULT_QLEN 2 /* double buffering by default */
87 static unsigned qmult = 5;
88 module_param(qmult, uint, S_IRUGO|S_IWUSR);
89 MODULE_PARM_DESC(qmult, "queue length multiplier at high/super speed");
91 /* for dual-speed hardware, use deeper queues at high/super speed */
92 static inline int qlen(struct usb_gadget *gadget)
94 if (gadget_is_dualspeed(gadget) && (gadget->speed == USB_SPEED_HIGH ||
95 gadget->speed == USB_SPEED_SUPER))
96 return qmult * DEFAULT_QLEN;
101 /*-------------------------------------------------------------------------*/
103 /* REVISIT there must be a better way than having two sets
112 #define xprintk(d, level, fmt, args...) \
113 printk(level "%s: " fmt , (d)->net->name , ## args)
117 #define DBG(dev, fmt, args...) \
118 xprintk(dev , KERN_DEBUG , fmt , ## args)
120 #define DBG(dev, fmt, args...) \
127 #define VDBG(dev, fmt, args...) \
131 #define ERROR(dev, fmt, args...) \
132 xprintk(dev , KERN_ERR , fmt , ## args)
133 #define INFO(dev, fmt, args...) \
134 xprintk(dev , KERN_INFO , fmt , ## args)
136 /*-------------------------------------------------------------------------*/
138 /* NETWORK DRIVER HOOKUP (to the layer above this driver) */
140 static int ueth_change_mtu(struct net_device *net, int new_mtu)
142 struct eth_dev *dev = netdev_priv(net);
146 /* don't change MTU on "live" link (peer won't know) */
147 spin_lock_irqsave(&dev->lock, flags);
150 else if (new_mtu <= ETH_HLEN || new_mtu > ETH_FRAME_LEN)
154 spin_unlock_irqrestore(&dev->lock, flags);
159 static void eth_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *p)
161 struct eth_dev *dev = netdev_priv(net);
163 strlcpy(p->driver, "g_ether", sizeof p->driver);
164 strlcpy(p->version, UETH__VERSION, sizeof p->version);
165 strlcpy(p->fw_version, dev->gadget->name, sizeof p->fw_version);
166 strlcpy(p->bus_info, dev_name(&dev->gadget->dev), sizeof p->bus_info);
169 /* REVISIT can also support:
170 * - WOL (by tracking suspends and issuing remote wakeup)
171 * - msglevel (implies updated messaging)
172 * - ... probably more ethtool ops
175 static const struct ethtool_ops ops = {
176 .get_drvinfo = eth_get_drvinfo,
177 .get_link = ethtool_op_get_link,
180 static void defer_kevent(struct eth_dev *dev, int flag)
182 if (test_and_set_bit(flag, &dev->todo))
184 if (!schedule_work(&dev->work))
185 ERROR(dev, "kevent %d may have been dropped\n", flag);
187 DBG(dev, "kevent %d scheduled\n", flag);
190 static void rx_complete(struct usb_ep *ep, struct usb_request *req);
193 rx_submit(struct eth_dev *dev, struct usb_request *req, gfp_t gfp_flags)
196 int retval = -ENOMEM;
201 spin_lock_irqsave(&dev->lock, flags);
203 out = dev->port_usb->out_ep;
206 spin_unlock_irqrestore(&dev->lock, flags);
212 /* Padding up to RX_EXTRA handles minor disagreements with host.
213 * Normally we use the USB "terminate on short read" convention;
214 * so allow up to (N*maxpacket), since that memory is normally
215 * already allocated. Some hardware doesn't deal well with short
216 * reads (e.g. DMA must be N*maxpacket), so for now don't trim a
217 * byte off the end (to force hardware errors on overflow).
219 * RNDIS uses internal framing, and explicitly allows senders to
220 * pad to end-of-packet. That's potentially nice for speed, but
221 * means receivers can't recover lost synch on their own (because
222 * new packets don't only start after a short RX).
224 size += sizeof(struct ethhdr) + dev->net->mtu + RX_EXTRA;
225 size += dev->port_usb->header_len;
226 size += out->maxpacket - 1;
227 size -= size % out->maxpacket;
229 if (dev->port_usb->is_fixed)
230 size = max_t(size_t, size, dev->port_usb->fixed_out_len);
232 skb = alloc_skb(size + NET_IP_ALIGN, gfp_flags);
234 DBG(dev, "no rx skb\n");
238 /* Some platforms perform better when IP packets are aligned,
239 * but on at least one, checksumming fails otherwise. Note:
240 * RNDIS headers involve variable numbers of LE32 values.
242 skb_reserve(skb, NET_IP_ALIGN);
244 req->buf = skb->data;
246 req->complete = rx_complete;
249 retval = usb_ep_queue(out, req, gfp_flags);
250 if (retval == -ENOMEM)
252 defer_kevent(dev, WORK_RX_MEMORY);
254 DBG(dev, "rx submit --> %d\n", retval);
256 dev_kfree_skb_any(skb);
257 spin_lock_irqsave(&dev->req_lock, flags);
258 list_add(&req->list, &dev->rx_reqs);
259 spin_unlock_irqrestore(&dev->req_lock, flags);
264 static void rx_complete(struct usb_ep *ep, struct usb_request *req)
266 struct sk_buff *skb = req->context, *skb2;
267 struct eth_dev *dev = ep->driver_data;
268 int status = req->status;
272 /* normal completion */
274 skb_put(skb, req->actual);
279 spin_lock_irqsave(&dev->lock, flags);
281 status = dev->unwrap(dev->port_usb,
285 dev_kfree_skb_any(skb);
288 spin_unlock_irqrestore(&dev->lock, flags);
290 skb_queue_tail(&dev->rx_frames, skb);
294 skb2 = skb_dequeue(&dev->rx_frames);
297 || ETH_HLEN > skb2->len
298 || skb2->len > ETH_FRAME_LEN) {
299 dev->net->stats.rx_errors++;
300 dev->net->stats.rx_length_errors++;
301 DBG(dev, "rx length %d\n", skb2->len);
302 dev_kfree_skb_any(skb2);
305 skb2->protocol = eth_type_trans(skb2, dev->net);
306 dev->net->stats.rx_packets++;
307 dev->net->stats.rx_bytes += skb2->len;
309 /* no buffer copies needed, unless hardware can't
312 status = netif_rx(skb2);
314 skb2 = skb_dequeue(&dev->rx_frames);
318 /* software-driven interface shutdown */
319 case -ECONNRESET: /* unlink */
320 case -ESHUTDOWN: /* disconnect etc */
321 VDBG(dev, "rx shutdown, code %d\n", status);
324 /* for hardware automagic (such as pxa) */
325 case -ECONNABORTED: /* endpoint reset */
326 DBG(dev, "rx %s reset\n", ep->name);
327 defer_kevent(dev, WORK_RX_MEMORY);
329 dev_kfree_skb_any(skb);
334 dev->net->stats.rx_over_errors++;
338 dev->net->stats.rx_errors++;
339 DBG(dev, "rx status %d\n", status);
344 dev_kfree_skb_any(skb);
345 if (!netif_running(dev->net)) {
347 spin_lock(&dev->req_lock);
348 list_add(&req->list, &dev->rx_reqs);
349 spin_unlock(&dev->req_lock);
353 rx_submit(dev, req, GFP_ATOMIC);
356 static int prealloc(struct list_head *list, struct usb_ep *ep, unsigned n)
359 struct usb_request *req;
364 /* queue/recycle up to N requests */
366 list_for_each_entry(req, list, list) {
371 req = usb_ep_alloc_request(ep, GFP_ATOMIC);
373 return list_empty(list) ? -ENOMEM : 0;
374 list_add(&req->list, list);
381 struct list_head *next;
383 next = req->list.next;
384 list_del(&req->list);
385 usb_ep_free_request(ep, req);
390 req = container_of(next, struct usb_request, list);
395 static int alloc_requests(struct eth_dev *dev, struct gether *link, unsigned n)
399 spin_lock(&dev->req_lock);
400 status = prealloc(&dev->tx_reqs, link->in_ep, n);
403 status = prealloc(&dev->rx_reqs, link->out_ep, n);
408 DBG(dev, "can't alloc requests\n");
410 spin_unlock(&dev->req_lock);
414 static void rx_fill(struct eth_dev *dev, gfp_t gfp_flags)
416 struct usb_request *req;
419 /* fill unused rxq slots with some skb */
420 spin_lock_irqsave(&dev->req_lock, flags);
421 while (!list_empty(&dev->rx_reqs)) {
422 req = container_of(dev->rx_reqs.next,
423 struct usb_request, list);
424 list_del_init(&req->list);
425 spin_unlock_irqrestore(&dev->req_lock, flags);
427 if (rx_submit(dev, req, gfp_flags) < 0) {
428 defer_kevent(dev, WORK_RX_MEMORY);
432 spin_lock_irqsave(&dev->req_lock, flags);
434 spin_unlock_irqrestore(&dev->req_lock, flags);
437 static void eth_work(struct work_struct *work)
439 struct eth_dev *dev = container_of(work, struct eth_dev, work);
441 if (test_and_clear_bit(WORK_RX_MEMORY, &dev->todo)) {
442 if (netif_running(dev->net))
443 rx_fill(dev, GFP_KERNEL);
447 DBG(dev, "work done, flags = 0x%lx\n", dev->todo);
450 static void tx_complete(struct usb_ep *ep, struct usb_request *req)
452 struct sk_buff *skb = req->context;
453 struct eth_dev *dev = ep->driver_data;
455 switch (req->status) {
457 dev->net->stats.tx_errors++;
458 VDBG(dev, "tx err %d\n", req->status);
460 case -ECONNRESET: /* unlink */
461 case -ESHUTDOWN: /* disconnect etc */
464 dev->net->stats.tx_bytes += skb->len;
466 dev->net->stats.tx_packets++;
468 spin_lock(&dev->req_lock);
469 list_add(&req->list, &dev->tx_reqs);
470 spin_unlock(&dev->req_lock);
471 dev_kfree_skb_any(skb);
473 atomic_dec(&dev->tx_qlen);
474 if (netif_carrier_ok(dev->net))
475 netif_wake_queue(dev->net);
478 static inline int is_promisc(u16 cdc_filter)
480 return cdc_filter & USB_CDC_PACKET_TYPE_PROMISCUOUS;
483 static netdev_tx_t eth_start_xmit(struct sk_buff *skb,
484 struct net_device *net)
486 struct eth_dev *dev = netdev_priv(net);
487 int length = skb->len;
489 struct usb_request *req = NULL;
494 spin_lock_irqsave(&dev->lock, flags);
496 in = dev->port_usb->in_ep;
497 cdc_filter = dev->port_usb->cdc_filter;
502 spin_unlock_irqrestore(&dev->lock, flags);
505 dev_kfree_skb_any(skb);
509 /* apply outgoing CDC or RNDIS filters */
510 if (!is_promisc(cdc_filter)) {
511 u8 *dest = skb->data;
513 if (is_multicast_ether_addr(dest)) {
516 /* ignores USB_CDC_PACKET_TYPE_MULTICAST and host
517 * SET_ETHERNET_MULTICAST_FILTERS requests
519 if (is_broadcast_ether_addr(dest))
520 type = USB_CDC_PACKET_TYPE_BROADCAST;
522 type = USB_CDC_PACKET_TYPE_ALL_MULTICAST;
523 if (!(cdc_filter & type)) {
524 dev_kfree_skb_any(skb);
528 /* ignores USB_CDC_PACKET_TYPE_DIRECTED */
531 spin_lock_irqsave(&dev->req_lock, flags);
533 * this freelist can be empty if an interrupt triggered disconnect()
534 * and reconfigured the gadget (shutting down this queue) after the
535 * network stack decided to xmit but before we got the spinlock.
537 if (list_empty(&dev->tx_reqs)) {
538 spin_unlock_irqrestore(&dev->req_lock, flags);
539 return NETDEV_TX_BUSY;
542 req = container_of(dev->tx_reqs.next, struct usb_request, list);
543 list_del(&req->list);
545 /* temporarily stop TX queue when the freelist empties */
546 if (list_empty(&dev->tx_reqs))
547 netif_stop_queue(net);
548 spin_unlock_irqrestore(&dev->req_lock, flags);
550 /* no buffer copies needed, unless the network stack did it
551 * or the hardware can't use skb buffers.
552 * or there's not enough space for extra headers we need
557 spin_lock_irqsave(&dev->lock, flags);
559 skb = dev->wrap(dev->port_usb, skb);
560 spin_unlock_irqrestore(&dev->lock, flags);
566 req->buf = skb->data;
568 req->complete = tx_complete;
570 /* NCM requires no zlp if transfer is dwNtbInMaxSize */
571 if (dev->port_usb->is_fixed &&
572 length == dev->port_usb->fixed_in_len &&
573 (length % in->maxpacket) == 0)
578 /* use zlp framing on tx for strict CDC-Ether conformance,
579 * though any robust network rx path ignores extra padding.
580 * and some hardware doesn't like to write zlps.
582 if (req->zero && !dev->zlp && (length % in->maxpacket) == 0)
585 req->length = length;
587 /* throttle high/super speed IRQ rate back slightly */
588 if (gadget_is_dualspeed(dev->gadget))
589 req->no_interrupt = (dev->gadget->speed == USB_SPEED_HIGH ||
590 dev->gadget->speed == USB_SPEED_SUPER)
591 ? ((atomic_read(&dev->tx_qlen) % qmult) != 0)
594 retval = usb_ep_queue(in, req, GFP_ATOMIC);
597 DBG(dev, "tx queue err %d\n", retval);
600 net->trans_start = jiffies;
601 atomic_inc(&dev->tx_qlen);
605 dev_kfree_skb_any(skb);
607 dev->net->stats.tx_dropped++;
608 spin_lock_irqsave(&dev->req_lock, flags);
609 if (list_empty(&dev->tx_reqs))
610 netif_start_queue(net);
611 list_add(&req->list, &dev->tx_reqs);
612 spin_unlock_irqrestore(&dev->req_lock, flags);
617 /*-------------------------------------------------------------------------*/
619 static void eth_start(struct eth_dev *dev, gfp_t gfp_flags)
621 DBG(dev, "%s\n", __func__);
623 /* fill the rx queue */
624 rx_fill(dev, gfp_flags);
626 /* and open the tx floodgates */
627 atomic_set(&dev->tx_qlen, 0);
628 netif_wake_queue(dev->net);
631 static int eth_open(struct net_device *net)
633 struct eth_dev *dev = netdev_priv(net);
636 DBG(dev, "%s\n", __func__);
637 if (netif_carrier_ok(dev->net))
638 eth_start(dev, GFP_KERNEL);
640 spin_lock_irq(&dev->lock);
641 link = dev->port_usb;
642 if (link && link->open)
644 spin_unlock_irq(&dev->lock);
649 static int eth_stop(struct net_device *net)
651 struct eth_dev *dev = netdev_priv(net);
654 VDBG(dev, "%s\n", __func__);
655 netif_stop_queue(net);
657 DBG(dev, "stop stats: rx/tx %ld/%ld, errs %ld/%ld\n",
658 dev->net->stats.rx_packets, dev->net->stats.tx_packets,
659 dev->net->stats.rx_errors, dev->net->stats.tx_errors
662 /* ensure there are no more active requests */
663 spin_lock_irqsave(&dev->lock, flags);
665 struct gether *link = dev->port_usb;
666 const struct usb_endpoint_descriptor *in;
667 const struct usb_endpoint_descriptor *out;
672 /* NOTE: we have no abort-queue primitive we could use
673 * to cancel all pending I/O. Instead, we disable then
674 * reenable the endpoints ... this idiom may leave toggle
675 * wrong, but that's a self-correcting error.
677 * REVISIT: we *COULD* just let the transfers complete at
678 * their own pace; the network stack can handle old packets.
679 * For the moment we leave this here, since it works.
681 in = link->in_ep->desc;
682 out = link->out_ep->desc;
683 usb_ep_disable(link->in_ep);
684 usb_ep_disable(link->out_ep);
685 if (netif_carrier_ok(net)) {
686 DBG(dev, "host still using in/out endpoints\n");
687 link->in_ep->desc = in;
688 link->out_ep->desc = out;
689 usb_ep_enable(link->in_ep);
690 usb_ep_enable(link->out_ep);
693 spin_unlock_irqrestore(&dev->lock, flags);
698 /*-------------------------------------------------------------------------*/
700 /* initial value, changed by "ifconfig usb0 hw ether xx:xx:xx:xx:xx:xx" */
701 static char *dev_addr;
702 module_param(dev_addr, charp, S_IRUGO);
703 MODULE_PARM_DESC(dev_addr, "Device Ethernet Address");
705 /* this address is invisible to ifconfig */
706 static char *host_addr;
707 module_param(host_addr, charp, S_IRUGO);
708 MODULE_PARM_DESC(host_addr, "Host Ethernet Address");
710 static int get_ether_addr(const char *str, u8 *dev_addr)
715 for (i = 0; i < 6; i++) {
718 if ((*str == '.') || (*str == ':'))
720 num = hex_to_bin(*str++) << 4;
721 num |= hex_to_bin(*str++);
724 if (is_valid_ether_addr(dev_addr))
727 eth_random_addr(dev_addr);
731 static struct eth_dev *the_dev;
733 static const struct net_device_ops eth_netdev_ops = {
734 .ndo_open = eth_open,
735 .ndo_stop = eth_stop,
736 .ndo_start_xmit = eth_start_xmit,
737 .ndo_change_mtu = ueth_change_mtu,
738 .ndo_set_mac_address = eth_mac_addr,
739 .ndo_validate_addr = eth_validate_addr,
742 static struct device_type gadget_type = {
747 * gether_setup_name - initialize one ethernet-over-usb link
748 * @g: gadget to associated with these links
749 * @ethaddr: NULL, or a buffer in which the ethernet address of the
750 * host side of the link is recorded
751 * @netname: name for network device (for example, "usb")
754 * This sets up the single network link that may be exported by a
755 * gadget driver using this framework. The link layer addresses are
756 * set up using module parameters.
758 * Returns negative errno, or zero on success
760 int gether_setup_name(struct usb_gadget *g, u8 ethaddr[ETH_ALEN],
764 struct net_device *net;
770 net = alloc_etherdev(sizeof *dev);
774 dev = netdev_priv(net);
775 spin_lock_init(&dev->lock);
776 spin_lock_init(&dev->req_lock);
777 INIT_WORK(&dev->work, eth_work);
778 INIT_LIST_HEAD(&dev->tx_reqs);
779 INIT_LIST_HEAD(&dev->rx_reqs);
781 skb_queue_head_init(&dev->rx_frames);
783 /* network device setup */
785 snprintf(net->name, sizeof(net->name), "%s%%d", netname);
787 if (get_ether_addr(dev_addr, net->dev_addr))
789 "using random %s ethernet address\n", "self");
790 if (get_ether_addr(host_addr, dev->host_mac))
792 "using random %s ethernet address\n", "host");
795 memcpy(ethaddr, dev->host_mac, ETH_ALEN);
797 net->netdev_ops = ð_netdev_ops;
799 SET_ETHTOOL_OPS(net, &ops);
802 SET_NETDEV_DEV(net, &g->dev);
803 SET_NETDEV_DEVTYPE(net, &gadget_type);
805 status = register_netdev(net);
807 dev_dbg(&g->dev, "register_netdev failed, %d\n", status);
810 INFO(dev, "MAC %pM\n", net->dev_addr);
811 INFO(dev, "HOST MAC %pM\n", dev->host_mac);
815 /* two kinds of host-initiated state changes:
816 * - iff DATA transfer is active, carrier is "on"
817 * - tx queueing enabled if open *and* carrier is "on"
819 netif_carrier_off(net);
826 * gether_cleanup - remove Ethernet-over-USB device
829 * This is called to free all resources allocated by @gether_setup().
831 void gether_cleanup(void)
836 unregister_netdev(the_dev->net);
837 flush_work(&the_dev->work);
838 free_netdev(the_dev->net);
845 * gether_connect - notify network layer that USB link is active
846 * @link: the USB link, set up with endpoints, descriptors matching
847 * current device speed, and any framing wrapper(s) set up.
848 * Context: irqs blocked
850 * This is called to activate endpoints and let the network layer know
851 * the connection is active ("carrier detect"). It may cause the I/O
852 * queues to open and start letting network packets flow, but will in
853 * any case activate the endpoints so that they respond properly to the
856 * Verify net_device pointer returned using IS_ERR(). If it doesn't
857 * indicate some error code (negative errno), ep->driver_data values
858 * have been overwritten.
860 struct net_device *gether_connect(struct gether *link)
862 struct eth_dev *dev = the_dev;
866 return ERR_PTR(-EINVAL);
868 link->in_ep->driver_data = dev;
869 result = usb_ep_enable(link->in_ep);
871 DBG(dev, "enable %s --> %d\n",
872 link->in_ep->name, result);
876 link->out_ep->driver_data = dev;
877 result = usb_ep_enable(link->out_ep);
879 DBG(dev, "enable %s --> %d\n",
880 link->out_ep->name, result);
885 result = alloc_requests(dev, link, qlen(dev->gadget));
888 dev->zlp = link->is_zlp_ok;
889 DBG(dev, "qlen %d\n", qlen(dev->gadget));
891 dev->header_len = link->header_len;
892 dev->unwrap = link->unwrap;
893 dev->wrap = link->wrap;
895 spin_lock(&dev->lock);
896 dev->port_usb = link;
898 if (netif_running(dev->net)) {
905 spin_unlock(&dev->lock);
907 netif_carrier_on(dev->net);
908 if (netif_running(dev->net))
909 eth_start(dev, GFP_ATOMIC);
911 /* on error, disable any endpoints */
913 (void) usb_ep_disable(link->out_ep);
915 (void) usb_ep_disable(link->in_ep);
918 /* caller is responsible for cleanup on error */
920 return ERR_PTR(result);
925 * gether_disconnect - notify network layer that USB link is inactive
926 * @link: the USB link, on which gether_connect() was called
927 * Context: irqs blocked
929 * This is called to deactivate endpoints and let the network layer know
930 * the connection went inactive ("no carrier").
932 * On return, the state is as if gether_connect() had never been called.
933 * The endpoints are inactive, and accordingly without active USB I/O.
934 * Pointers to endpoint descriptors and endpoint private data are nulled.
936 void gether_disconnect(struct gether *link)
938 struct eth_dev *dev = link->ioport;
939 struct usb_request *req;
945 DBG(dev, "%s\n", __func__);
947 netif_stop_queue(dev->net);
948 netif_carrier_off(dev->net);
950 /* disable endpoints, forcing (synchronous) completion
951 * of all pending i/o. then free the request objects
952 * and forget about the endpoints.
954 usb_ep_disable(link->in_ep);
955 spin_lock(&dev->req_lock);
956 while (!list_empty(&dev->tx_reqs)) {
957 req = container_of(dev->tx_reqs.next,
958 struct usb_request, list);
959 list_del(&req->list);
961 spin_unlock(&dev->req_lock);
962 usb_ep_free_request(link->in_ep, req);
963 spin_lock(&dev->req_lock);
965 spin_unlock(&dev->req_lock);
966 link->in_ep->driver_data = NULL;
967 link->in_ep->desc = NULL;
969 usb_ep_disable(link->out_ep);
970 spin_lock(&dev->req_lock);
971 while (!list_empty(&dev->rx_reqs)) {
972 req = container_of(dev->rx_reqs.next,
973 struct usb_request, list);
974 list_del(&req->list);
976 spin_unlock(&dev->req_lock);
977 usb_ep_free_request(link->out_ep, req);
978 spin_lock(&dev->req_lock);
980 spin_unlock(&dev->req_lock);
981 link->out_ep->driver_data = NULL;
982 link->out_ep->desc = NULL;
984 /* finish forgetting about this USB link episode */
989 spin_lock(&dev->lock);
990 dev->port_usb = NULL;
992 spin_unlock(&dev->lock);