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.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 /* #define VERBOSE_DEBUG */
25 #include <linux/kernel.h>
26 #include <linux/gfp.h>
27 #include <linux/device.h>
28 #include <linux/ctype.h>
29 #include <linux/etherdevice.h>
30 #include <linux/ethtool.h>
36 * This component encapsulates the Ethernet link glue needed to provide
37 * one (!) network link through the USB gadget stack, normally "usb0".
39 * The control and data models are handled by the function driver which
40 * connects to this code; such as CDC Ethernet (ECM or EEM),
41 * "CDC Subset", or RNDIS. That includes all descriptor and endpoint
44 * Link level addressing is handled by this component using module
45 * parameters; if no such parameters are provided, random link level
46 * addresses are used. Each end of the link uses one address. The
47 * host end address is exported in various ways, and is often recorded
48 * in configuration databases.
50 * The driver which assembles each configuration using such a link is
51 * responsible for ensuring that each configuration includes at most one
52 * instance of is network link. (The network layer provides ways for
53 * this single "physical" link to be used by multiple virtual links.)
56 #define UETH__VERSION "29-May-2008"
59 /* lock is held while accessing port_usb
60 * or updating its backlink port_usb->ioport
63 struct gether *port_usb;
65 struct net_device *net;
66 struct usb_gadget *gadget;
68 spinlock_t req_lock; /* guard {rx,tx}_reqs */
69 struct list_head tx_reqs, rx_reqs;
72 struct sk_buff_head rx_frames;
75 struct sk_buff *(*wrap)(struct gether *, struct sk_buff *skb);
76 int (*unwrap)(struct gether *,
78 struct sk_buff_head *list);
80 struct work_struct work;
83 #define WORK_RX_MEMORY 0
86 u8 host_mac[ETH_ALEN];
89 /*-------------------------------------------------------------------------*/
91 #define RX_EXTRA 20 /* bytes guarding against rx overflows */
93 #define DEFAULT_QLEN 2 /* double buffering by default */
96 #ifdef CONFIG_USB_GADGET_DUALSPEED
98 static unsigned qmult = 5;
99 module_param(qmult, uint, S_IRUGO|S_IWUSR);
100 MODULE_PARM_DESC(qmult, "queue length multiplier at high/super speed");
102 #else /* full speed (low speed doesn't do bulk) */
106 /* for dual-speed hardware, use deeper queues at high/super speed */
107 static inline int qlen(struct usb_gadget *gadget)
109 if (gadget_is_dualspeed(gadget) && (gadget->speed == USB_SPEED_HIGH ||
110 gadget->speed == USB_SPEED_SUPER))
111 return qmult * DEFAULT_QLEN;
116 /*-------------------------------------------------------------------------*/
118 /* REVISIT there must be a better way than having two sets
127 #define xprintk(d, level, fmt, args...) \
128 printk(level "%s: " fmt , (d)->net->name , ## args)
132 #define DBG(dev, fmt, args...) \
133 xprintk(dev , KERN_DEBUG , fmt , ## args)
135 #define DBG(dev, fmt, args...) \
142 #define VDBG(dev, fmt, args...) \
146 #define ERROR(dev, fmt, args...) \
147 xprintk(dev , KERN_ERR , fmt , ## args)
148 #define INFO(dev, fmt, args...) \
149 xprintk(dev , KERN_INFO , fmt , ## args)
151 /*-------------------------------------------------------------------------*/
153 /* NETWORK DRIVER HOOKUP (to the layer above this driver) */
155 static int ueth_change_mtu(struct net_device *net, int new_mtu)
157 struct eth_dev *dev = netdev_priv(net);
161 /* don't change MTU on "live" link (peer won't know) */
162 spin_lock_irqsave(&dev->lock, flags);
165 else if (new_mtu <= ETH_HLEN || new_mtu > ETH_FRAME_LEN)
169 spin_unlock_irqrestore(&dev->lock, flags);
174 static void eth_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *p)
176 struct eth_dev *dev = netdev_priv(net);
178 strlcpy(p->driver, "g_ether", sizeof p->driver);
179 strlcpy(p->version, UETH__VERSION, sizeof p->version);
180 strlcpy(p->fw_version, dev->gadget->name, sizeof p->fw_version);
181 strlcpy(p->bus_info, dev_name(&dev->gadget->dev), sizeof p->bus_info);
184 /* REVISIT can also support:
185 * - WOL (by tracking suspends and issuing remote wakeup)
186 * - msglevel (implies updated messaging)
187 * - ... probably more ethtool ops
190 static const struct ethtool_ops ops = {
191 .get_drvinfo = eth_get_drvinfo,
192 .get_link = ethtool_op_get_link,
195 static void defer_kevent(struct eth_dev *dev, int flag)
197 if (test_and_set_bit(flag, &dev->todo))
199 if (!schedule_work(&dev->work))
200 ERROR(dev, "kevent %d may have been dropped\n", flag);
202 DBG(dev, "kevent %d scheduled\n", flag);
205 static void rx_complete(struct usb_ep *ep, struct usb_request *req);
208 rx_submit(struct eth_dev *dev, struct usb_request *req, gfp_t gfp_flags)
211 int retval = -ENOMEM;
216 spin_lock_irqsave(&dev->lock, flags);
218 out = dev->port_usb->out_ep;
221 spin_unlock_irqrestore(&dev->lock, flags);
227 /* Padding up to RX_EXTRA handles minor disagreements with host.
228 * Normally we use the USB "terminate on short read" convention;
229 * so allow up to (N*maxpacket), since that memory is normally
230 * already allocated. Some hardware doesn't deal well with short
231 * reads (e.g. DMA must be N*maxpacket), so for now don't trim a
232 * byte off the end (to force hardware errors on overflow).
234 * RNDIS uses internal framing, and explicitly allows senders to
235 * pad to end-of-packet. That's potentially nice for speed, but
236 * means receivers can't recover lost synch on their own (because
237 * new packets don't only start after a short RX).
239 size += sizeof(struct ethhdr) + dev->net->mtu + RX_EXTRA;
240 size += dev->port_usb->header_len;
241 size += out->maxpacket - 1;
242 size -= size % out->maxpacket;
244 if (dev->port_usb->is_fixed)
245 size = max_t(size_t, size, dev->port_usb->fixed_out_len);
247 skb = alloc_skb(size + NET_IP_ALIGN, gfp_flags);
249 DBG(dev, "no rx skb\n");
253 /* Some platforms perform better when IP packets are aligned,
254 * but on at least one, checksumming fails otherwise. Note:
255 * RNDIS headers involve variable numbers of LE32 values.
257 skb_reserve(skb, NET_IP_ALIGN);
259 req->buf = skb->data;
261 req->complete = rx_complete;
264 retval = usb_ep_queue(out, req, gfp_flags);
265 if (retval == -ENOMEM)
267 defer_kevent(dev, WORK_RX_MEMORY);
269 DBG(dev, "rx submit --> %d\n", retval);
271 dev_kfree_skb_any(skb);
272 spin_lock_irqsave(&dev->req_lock, flags);
273 list_add(&req->list, &dev->rx_reqs);
274 spin_unlock_irqrestore(&dev->req_lock, flags);
279 static void rx_complete(struct usb_ep *ep, struct usb_request *req)
281 struct sk_buff *skb = req->context, *skb2;
282 struct eth_dev *dev = ep->driver_data;
283 int status = req->status;
287 /* normal completion */
289 skb_put(skb, req->actual);
294 spin_lock_irqsave(&dev->lock, flags);
296 status = dev->unwrap(dev->port_usb,
300 dev_kfree_skb_any(skb);
303 spin_unlock_irqrestore(&dev->lock, flags);
305 skb_queue_tail(&dev->rx_frames, skb);
309 skb2 = skb_dequeue(&dev->rx_frames);
312 || ETH_HLEN > skb2->len
313 || skb2->len > ETH_FRAME_LEN) {
314 dev->net->stats.rx_errors++;
315 dev->net->stats.rx_length_errors++;
316 DBG(dev, "rx length %d\n", skb2->len);
317 dev_kfree_skb_any(skb2);
320 skb2->protocol = eth_type_trans(skb2, dev->net);
321 dev->net->stats.rx_packets++;
322 dev->net->stats.rx_bytes += skb2->len;
324 /* no buffer copies needed, unless hardware can't
327 status = netif_rx(skb2);
329 skb2 = skb_dequeue(&dev->rx_frames);
333 /* software-driven interface shutdown */
334 case -ECONNRESET: /* unlink */
335 case -ESHUTDOWN: /* disconnect etc */
336 VDBG(dev, "rx shutdown, code %d\n", status);
339 /* for hardware automagic (such as pxa) */
340 case -ECONNABORTED: /* endpoint reset */
341 DBG(dev, "rx %s reset\n", ep->name);
342 defer_kevent(dev, WORK_RX_MEMORY);
344 dev_kfree_skb_any(skb);
349 dev->net->stats.rx_over_errors++;
353 dev->net->stats.rx_errors++;
354 DBG(dev, "rx status %d\n", status);
359 dev_kfree_skb_any(skb);
360 if (!netif_running(dev->net)) {
362 spin_lock(&dev->req_lock);
363 list_add(&req->list, &dev->rx_reqs);
364 spin_unlock(&dev->req_lock);
368 rx_submit(dev, req, GFP_ATOMIC);
371 static int prealloc(struct list_head *list, struct usb_ep *ep, unsigned n)
374 struct usb_request *req;
379 /* queue/recycle up to N requests */
381 list_for_each_entry(req, list, list) {
386 req = usb_ep_alloc_request(ep, GFP_ATOMIC);
388 return list_empty(list) ? -ENOMEM : 0;
389 list_add(&req->list, list);
396 struct list_head *next;
398 next = req->list.next;
399 list_del(&req->list);
400 usb_ep_free_request(ep, req);
405 req = container_of(next, struct usb_request, list);
410 static int alloc_requests(struct eth_dev *dev, struct gether *link, unsigned n)
414 spin_lock(&dev->req_lock);
415 status = prealloc(&dev->tx_reqs, link->in_ep, n);
418 status = prealloc(&dev->rx_reqs, link->out_ep, n);
423 DBG(dev, "can't alloc requests\n");
425 spin_unlock(&dev->req_lock);
429 static void rx_fill(struct eth_dev *dev, gfp_t gfp_flags)
431 struct usb_request *req;
434 /* fill unused rxq slots with some skb */
435 spin_lock_irqsave(&dev->req_lock, flags);
436 while (!list_empty(&dev->rx_reqs)) {
437 req = container_of(dev->rx_reqs.next,
438 struct usb_request, list);
439 list_del_init(&req->list);
440 spin_unlock_irqrestore(&dev->req_lock, flags);
442 if (rx_submit(dev, req, gfp_flags) < 0) {
443 defer_kevent(dev, WORK_RX_MEMORY);
447 spin_lock_irqsave(&dev->req_lock, flags);
449 spin_unlock_irqrestore(&dev->req_lock, flags);
452 static void eth_work(struct work_struct *work)
454 struct eth_dev *dev = container_of(work, struct eth_dev, work);
456 if (test_and_clear_bit(WORK_RX_MEMORY, &dev->todo)) {
457 if (netif_running(dev->net))
458 rx_fill(dev, GFP_KERNEL);
462 DBG(dev, "work done, flags = 0x%lx\n", dev->todo);
465 static void tx_complete(struct usb_ep *ep, struct usb_request *req)
467 struct sk_buff *skb = req->context;
468 struct eth_dev *dev = ep->driver_data;
470 switch (req->status) {
472 dev->net->stats.tx_errors++;
473 VDBG(dev, "tx err %d\n", req->status);
475 case -ECONNRESET: /* unlink */
476 case -ESHUTDOWN: /* disconnect etc */
479 dev->net->stats.tx_bytes += skb->len;
481 dev->net->stats.tx_packets++;
483 spin_lock(&dev->req_lock);
484 list_add(&req->list, &dev->tx_reqs);
485 spin_unlock(&dev->req_lock);
486 dev_kfree_skb_any(skb);
488 atomic_dec(&dev->tx_qlen);
489 if (netif_carrier_ok(dev->net))
490 netif_wake_queue(dev->net);
493 static inline int is_promisc(u16 cdc_filter)
495 return cdc_filter & USB_CDC_PACKET_TYPE_PROMISCUOUS;
498 static netdev_tx_t eth_start_xmit(struct sk_buff *skb,
499 struct net_device *net)
501 struct eth_dev *dev = netdev_priv(net);
502 int length = skb->len;
504 struct usb_request *req = NULL;
509 spin_lock_irqsave(&dev->lock, flags);
511 in = dev->port_usb->in_ep;
512 cdc_filter = dev->port_usb->cdc_filter;
517 spin_unlock_irqrestore(&dev->lock, flags);
520 dev_kfree_skb_any(skb);
524 /* apply outgoing CDC or RNDIS filters */
525 if (!is_promisc(cdc_filter)) {
526 u8 *dest = skb->data;
528 if (is_multicast_ether_addr(dest)) {
531 /* ignores USB_CDC_PACKET_TYPE_MULTICAST and host
532 * SET_ETHERNET_MULTICAST_FILTERS requests
534 if (is_broadcast_ether_addr(dest))
535 type = USB_CDC_PACKET_TYPE_BROADCAST;
537 type = USB_CDC_PACKET_TYPE_ALL_MULTICAST;
538 if (!(cdc_filter & type)) {
539 dev_kfree_skb_any(skb);
543 /* ignores USB_CDC_PACKET_TYPE_DIRECTED */
546 spin_lock_irqsave(&dev->req_lock, flags);
548 * this freelist can be empty if an interrupt triggered disconnect()
549 * and reconfigured the gadget (shutting down this queue) after the
550 * network stack decided to xmit but before we got the spinlock.
552 if (list_empty(&dev->tx_reqs)) {
553 spin_unlock_irqrestore(&dev->req_lock, flags);
554 return NETDEV_TX_BUSY;
557 req = container_of(dev->tx_reqs.next, struct usb_request, list);
558 list_del(&req->list);
560 /* temporarily stop TX queue when the freelist empties */
561 if (list_empty(&dev->tx_reqs))
562 netif_stop_queue(net);
563 spin_unlock_irqrestore(&dev->req_lock, flags);
565 /* no buffer copies needed, unless the network stack did it
566 * or the hardware can't use skb buffers.
567 * or there's not enough space for extra headers we need
572 spin_lock_irqsave(&dev->lock, flags);
574 skb = dev->wrap(dev->port_usb, skb);
575 spin_unlock_irqrestore(&dev->lock, flags);
581 req->buf = skb->data;
583 req->complete = tx_complete;
585 /* NCM requires no zlp if transfer is dwNtbInMaxSize */
586 if (dev->port_usb->is_fixed &&
587 length == dev->port_usb->fixed_in_len &&
588 (length % in->maxpacket) == 0)
593 /* use zlp framing on tx for strict CDC-Ether conformance,
594 * though any robust network rx path ignores extra padding.
595 * and some hardware doesn't like to write zlps.
597 if (req->zero && !dev->zlp && (length % in->maxpacket) == 0)
600 req->length = length;
602 /* throttle high/super speed IRQ rate back slightly */
603 if (gadget_is_dualspeed(dev->gadget))
604 req->no_interrupt = (dev->gadget->speed == USB_SPEED_HIGH ||
605 dev->gadget->speed == USB_SPEED_SUPER)
606 ? ((atomic_read(&dev->tx_qlen) % qmult) != 0)
609 retval = usb_ep_queue(in, req, GFP_ATOMIC);
612 DBG(dev, "tx queue err %d\n", retval);
615 net->trans_start = jiffies;
616 atomic_inc(&dev->tx_qlen);
620 dev_kfree_skb_any(skb);
622 dev->net->stats.tx_dropped++;
623 spin_lock_irqsave(&dev->req_lock, flags);
624 if (list_empty(&dev->tx_reqs))
625 netif_start_queue(net);
626 list_add(&req->list, &dev->tx_reqs);
627 spin_unlock_irqrestore(&dev->req_lock, flags);
632 /*-------------------------------------------------------------------------*/
634 static void eth_start(struct eth_dev *dev, gfp_t gfp_flags)
636 DBG(dev, "%s\n", __func__);
638 /* fill the rx queue */
639 rx_fill(dev, gfp_flags);
641 /* and open the tx floodgates */
642 atomic_set(&dev->tx_qlen, 0);
643 netif_wake_queue(dev->net);
646 static int eth_open(struct net_device *net)
648 struct eth_dev *dev = netdev_priv(net);
651 DBG(dev, "%s\n", __func__);
652 if (netif_carrier_ok(dev->net))
653 eth_start(dev, GFP_KERNEL);
655 spin_lock_irq(&dev->lock);
656 link = dev->port_usb;
657 if (link && link->open)
659 spin_unlock_irq(&dev->lock);
664 static int eth_stop(struct net_device *net)
666 struct eth_dev *dev = netdev_priv(net);
669 VDBG(dev, "%s\n", __func__);
670 netif_stop_queue(net);
672 DBG(dev, "stop stats: rx/tx %ld/%ld, errs %ld/%ld\n",
673 dev->net->stats.rx_packets, dev->net->stats.tx_packets,
674 dev->net->stats.rx_errors, dev->net->stats.tx_errors
677 /* ensure there are no more active requests */
678 spin_lock_irqsave(&dev->lock, flags);
680 struct gether *link = dev->port_usb;
685 /* NOTE: we have no abort-queue primitive we could use
686 * to cancel all pending I/O. Instead, we disable then
687 * reenable the endpoints ... this idiom may leave toggle
688 * wrong, but that's a self-correcting error.
690 * REVISIT: we *COULD* just let the transfers complete at
691 * their own pace; the network stack can handle old packets.
692 * For the moment we leave this here, since it works.
694 usb_ep_disable(link->in_ep);
695 usb_ep_disable(link->out_ep);
696 if (netif_carrier_ok(net)) {
697 DBG(dev, "host still using in/out endpoints\n");
698 usb_ep_enable(link->in_ep);
699 usb_ep_enable(link->out_ep);
702 spin_unlock_irqrestore(&dev->lock, flags);
707 /*-------------------------------------------------------------------------*/
709 /* initial value, changed by "ifconfig usb0 hw ether xx:xx:xx:xx:xx:xx" */
710 static char *dev_addr;
711 module_param(dev_addr, charp, S_IRUGO);
712 MODULE_PARM_DESC(dev_addr, "Device Ethernet Address");
714 /* this address is invisible to ifconfig */
715 static char *host_addr;
716 module_param(host_addr, charp, S_IRUGO);
717 MODULE_PARM_DESC(host_addr, "Host Ethernet Address");
719 static int get_ether_addr(const char *str, u8 *dev_addr)
724 for (i = 0; i < 6; i++) {
727 if ((*str == '.') || (*str == ':'))
729 num = hex_to_bin(*str++) << 4;
730 num |= hex_to_bin(*str++);
733 if (is_valid_ether_addr(dev_addr))
736 random_ether_addr(dev_addr);
740 static struct eth_dev *the_dev;
742 static const struct net_device_ops eth_netdev_ops = {
743 .ndo_open = eth_open,
744 .ndo_stop = eth_stop,
745 .ndo_start_xmit = eth_start_xmit,
746 .ndo_change_mtu = ueth_change_mtu,
747 .ndo_set_mac_address = eth_mac_addr,
748 .ndo_validate_addr = eth_validate_addr,
751 static struct device_type gadget_type = {
756 * gether_setup - initialize one ethernet-over-usb link
757 * @g: gadget to associated with these links
758 * @ethaddr: NULL, or a buffer in which the ethernet address of the
759 * host side of the link is recorded
762 * This sets up the single network link that may be exported by a
763 * gadget driver using this framework. The link layer addresses are
764 * set up using module parameters.
766 * Returns negative errno, or zero on success
768 int gether_setup(struct usb_gadget *g, u8 ethaddr[ETH_ALEN])
771 struct net_device *net;
777 net = alloc_etherdev(sizeof *dev);
781 dev = netdev_priv(net);
782 spin_lock_init(&dev->lock);
783 spin_lock_init(&dev->req_lock);
784 INIT_WORK(&dev->work, eth_work);
785 INIT_LIST_HEAD(&dev->tx_reqs);
786 INIT_LIST_HEAD(&dev->rx_reqs);
788 skb_queue_head_init(&dev->rx_frames);
790 /* network device setup */
792 strcpy(net->name, "usb%d");
794 if (get_ether_addr(dev_addr, net->dev_addr))
796 "using random %s ethernet address\n", "self");
797 if (get_ether_addr(host_addr, dev->host_mac))
799 "using random %s ethernet address\n", "host");
802 memcpy(ethaddr, dev->host_mac, ETH_ALEN);
804 net->netdev_ops = ð_netdev_ops;
806 SET_ETHTOOL_OPS(net, &ops);
808 /* two kinds of host-initiated state changes:
809 * - iff DATA transfer is active, carrier is "on"
810 * - tx queueing enabled if open *and* carrier is "on"
812 netif_carrier_off(net);
815 SET_NETDEV_DEV(net, &g->dev);
816 SET_NETDEV_DEVTYPE(net, &gadget_type);
818 status = register_netdev(net);
820 dev_dbg(&g->dev, "register_netdev failed, %d\n", status);
823 INFO(dev, "MAC %pM\n", net->dev_addr);
824 INFO(dev, "HOST MAC %pM\n", dev->host_mac);
833 * gether_cleanup - remove Ethernet-over-USB device
836 * This is called to free all resources allocated by @gether_setup().
838 void gether_cleanup(void)
843 unregister_netdev(the_dev->net);
844 flush_work_sync(&the_dev->work);
845 free_netdev(the_dev->net);
852 * gether_connect - notify network layer that USB link is active
853 * @link: the USB link, set up with endpoints, descriptors matching
854 * current device speed, and any framing wrapper(s) set up.
855 * Context: irqs blocked
857 * This is called to activate endpoints and let the network layer know
858 * the connection is active ("carrier detect"). It may cause the I/O
859 * queues to open and start letting network packets flow, but will in
860 * any case activate the endpoints so that they respond properly to the
863 * Verify net_device pointer returned using IS_ERR(). If it doesn't
864 * indicate some error code (negative errno), ep->driver_data values
865 * have been overwritten.
867 struct net_device *gether_connect(struct gether *link)
869 struct eth_dev *dev = the_dev;
873 return ERR_PTR(-EINVAL);
875 link->in_ep->driver_data = dev;
876 result = usb_ep_enable(link->in_ep);
878 DBG(dev, "enable %s --> %d\n",
879 link->in_ep->name, result);
883 link->out_ep->driver_data = dev;
884 result = usb_ep_enable(link->out_ep);
886 DBG(dev, "enable %s --> %d\n",
887 link->out_ep->name, result);
892 result = alloc_requests(dev, link, qlen(dev->gadget));
895 dev->zlp = link->is_zlp_ok;
896 DBG(dev, "qlen %d\n", qlen(dev->gadget));
898 dev->header_len = link->header_len;
899 dev->unwrap = link->unwrap;
900 dev->wrap = link->wrap;
902 spin_lock(&dev->lock);
903 dev->port_usb = link;
905 if (netif_running(dev->net)) {
912 spin_unlock(&dev->lock);
914 netif_carrier_on(dev->net);
915 if (netif_running(dev->net))
916 eth_start(dev, GFP_ATOMIC);
918 /* on error, disable any endpoints */
920 (void) usb_ep_disable(link->out_ep);
922 (void) usb_ep_disable(link->in_ep);
925 /* caller is responsible for cleanup on error */
927 return ERR_PTR(result);
932 * gether_disconnect - notify network layer that USB link is inactive
933 * @link: the USB link, on which gether_connect() was called
934 * Context: irqs blocked
936 * This is called to deactivate endpoints and let the network layer know
937 * the connection went inactive ("no carrier").
939 * On return, the state is as if gether_connect() had never been called.
940 * The endpoints are inactive, and accordingly without active USB I/O.
941 * Pointers to endpoint descriptors and endpoint private data are nulled.
943 void gether_disconnect(struct gether *link)
945 struct eth_dev *dev = link->ioport;
946 struct usb_request *req;
952 DBG(dev, "%s\n", __func__);
954 netif_stop_queue(dev->net);
955 netif_carrier_off(dev->net);
957 /* disable endpoints, forcing (synchronous) completion
958 * of all pending i/o. then free the request objects
959 * and forget about the endpoints.
961 usb_ep_disable(link->in_ep);
962 spin_lock(&dev->req_lock);
963 while (!list_empty(&dev->tx_reqs)) {
964 req = container_of(dev->tx_reqs.next,
965 struct usb_request, list);
966 list_del(&req->list);
968 spin_unlock(&dev->req_lock);
969 usb_ep_free_request(link->in_ep, req);
970 spin_lock(&dev->req_lock);
972 spin_unlock(&dev->req_lock);
973 link->in_ep->driver_data = NULL;
974 link->in_ep->desc = NULL;
976 usb_ep_disable(link->out_ep);
977 spin_lock(&dev->req_lock);
978 while (!list_empty(&dev->rx_reqs)) {
979 req = container_of(dev->rx_reqs.next,
980 struct usb_request, list);
981 list_del(&req->list);
983 spin_unlock(&dev->req_lock);
984 usb_ep_free_request(link->out_ep, req);
985 spin_lock(&dev->req_lock);
987 spin_unlock(&dev->req_lock);
988 link->out_ep->driver_data = NULL;
989 link->out_ep->desc = NULL;
991 /* finish forgetting about this USB link episode */
996 spin_lock(&dev->lock);
997 dev->port_usb = NULL;
999 spin_unlock(&dev->lock);