1 // SPDX-License-Identifier: GPL-2.0+
3 * u_ether.c -- Ethernet-over-USB link layer utilities for Gadget stack
5 * Copyright (C) 2003-2005,2008 David Brownell
6 * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
7 * Copyright (C) 2008 Nokia Corporation
10 /* #define VERBOSE_DEBUG */
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/gfp.h>
15 #include <linux/device.h>
16 #include <linux/ctype.h>
17 #include <linux/etherdevice.h>
18 #include <linux/ethtool.h>
19 #include <linux/if_vlan.h>
25 * This component encapsulates the Ethernet link glue needed to provide
26 * one (!) network link through the USB gadget stack, normally "usb0".
28 * The control and data models are handled by the function driver which
29 * connects to this code; such as CDC Ethernet (ECM or EEM),
30 * "CDC Subset", or RNDIS. That includes all descriptor and endpoint
33 * Link level addressing is handled by this component using module
34 * parameters; if no such parameters are provided, random link level
35 * addresses are used. Each end of the link uses one address. The
36 * host end address is exported in various ways, and is often recorded
37 * in configuration databases.
39 * The driver which assembles each configuration using such a link is
40 * responsible for ensuring that each configuration includes at most one
41 * instance of is network link. (The network layer provides ways for
42 * this single "physical" link to be used by multiple virtual links.)
45 #define UETH__VERSION "29-May-2008"
47 /* Experiments show that both Linux and Windows hosts allow up to 16k
48 * frame sizes. Set the max size to 15k+52 to prevent allocating 32k
49 * blocks and still have efficient handling. */
50 #define GETHER_MAX_ETH_FRAME_LEN 15412
53 /* lock is held while accessing port_usb
56 struct gether *port_usb;
58 struct net_device *net;
59 struct usb_gadget *gadget;
61 spinlock_t req_lock; /* guard {rx,tx}_reqs */
62 struct list_head tx_reqs, rx_reqs;
65 struct sk_buff_head rx_frames;
70 struct sk_buff *(*wrap)(struct gether *, struct sk_buff *skb);
71 int (*unwrap)(struct gether *,
73 struct sk_buff_head *list);
75 struct work_struct work;
78 #define WORK_RX_MEMORY 0
82 u8 host_mac[ETH_ALEN];
86 /*-------------------------------------------------------------------------*/
88 #define RX_EXTRA 20 /* bytes guarding against rx overflows */
90 #define DEFAULT_QLEN 2 /* double buffering by default */
92 /* for dual-speed hardware, use deeper queues at high/super speed */
93 static inline int qlen(struct usb_gadget *gadget, unsigned qmult)
95 if (gadget_is_dualspeed(gadget) && (gadget->speed == USB_SPEED_HIGH ||
96 gadget->speed == USB_SPEED_SUPER))
97 return qmult * DEFAULT_QLEN;
102 /*-------------------------------------------------------------------------*/
104 /* REVISIT there must be a better way than having two sets
113 #define xprintk(d, level, fmt, args...) \
114 printk(level "%s: " fmt , (d)->net->name , ## args)
118 #define DBG(dev, fmt, args...) \
119 xprintk(dev , KERN_DEBUG , fmt , ## args)
121 #define DBG(dev, fmt, args...) \
128 #define VDBG(dev, fmt, args...) \
132 #define ERROR(dev, fmt, args...) \
133 xprintk(dev , KERN_ERR , fmt , ## args)
134 #define INFO(dev, fmt, args...) \
135 xprintk(dev , KERN_INFO , fmt , ## args)
137 /*-------------------------------------------------------------------------*/
139 /* NETWORK DRIVER HOOKUP (to the layer above this driver) */
141 static void eth_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *p)
143 struct eth_dev *dev = netdev_priv(net);
145 strlcpy(p->driver, "g_ether", sizeof(p->driver));
146 strlcpy(p->version, UETH__VERSION, sizeof(p->version));
147 strlcpy(p->fw_version, dev->gadget->name, sizeof(p->fw_version));
148 strlcpy(p->bus_info, dev_name(&dev->gadget->dev), sizeof(p->bus_info));
151 /* REVISIT can also support:
152 * - WOL (by tracking suspends and issuing remote wakeup)
153 * - msglevel (implies updated messaging)
154 * - ... probably more ethtool ops
157 static const struct ethtool_ops ops = {
158 .get_drvinfo = eth_get_drvinfo,
159 .get_link = ethtool_op_get_link,
162 static void defer_kevent(struct eth_dev *dev, int flag)
164 if (test_and_set_bit(flag, &dev->todo))
166 if (!schedule_work(&dev->work))
167 ERROR(dev, "kevent %d may have been dropped\n", flag);
169 DBG(dev, "kevent %d scheduled\n", flag);
172 static void rx_complete(struct usb_ep *ep, struct usb_request *req);
175 rx_submit(struct eth_dev *dev, struct usb_request *req, gfp_t gfp_flags)
177 struct usb_gadget *g = dev->gadget;
179 int retval = -ENOMEM;
184 spin_lock_irqsave(&dev->lock, flags);
186 out = dev->port_usb->out_ep;
189 spin_unlock_irqrestore(&dev->lock, flags);
195 /* Padding up to RX_EXTRA handles minor disagreements with host.
196 * Normally we use the USB "terminate on short read" convention;
197 * so allow up to (N*maxpacket), since that memory is normally
198 * already allocated. Some hardware doesn't deal well with short
199 * reads (e.g. DMA must be N*maxpacket), so for now don't trim a
200 * byte off the end (to force hardware errors on overflow).
202 * RNDIS uses internal framing, and explicitly allows senders to
203 * pad to end-of-packet. That's potentially nice for speed, but
204 * means receivers can't recover lost synch on their own (because
205 * new packets don't only start after a short RX).
207 size += sizeof(struct ethhdr) + dev->net->mtu + RX_EXTRA;
208 size += dev->port_usb->header_len;
210 if (g->quirk_ep_out_aligned_size) {
211 size += out->maxpacket - 1;
212 size -= size % out->maxpacket;
215 if (dev->port_usb->is_fixed)
216 size = max_t(size_t, size, dev->port_usb->fixed_out_len);
218 skb = __netdev_alloc_skb(dev->net, size + NET_IP_ALIGN, gfp_flags);
220 DBG(dev, "no rx skb\n");
224 /* Some platforms perform better when IP packets are aligned,
225 * but on at least one, checksumming fails otherwise. Note:
226 * RNDIS headers involve variable numbers of LE32 values.
228 if (likely(!dev->no_skb_reserve))
229 skb_reserve(skb, NET_IP_ALIGN);
231 req->buf = skb->data;
233 req->complete = rx_complete;
236 retval = usb_ep_queue(out, req, gfp_flags);
237 if (retval == -ENOMEM)
239 defer_kevent(dev, WORK_RX_MEMORY);
241 DBG(dev, "rx submit --> %d\n", retval);
243 dev_kfree_skb_any(skb);
244 spin_lock_irqsave(&dev->req_lock, flags);
245 list_add(&req->list, &dev->rx_reqs);
246 spin_unlock_irqrestore(&dev->req_lock, flags);
251 static void rx_complete(struct usb_ep *ep, struct usb_request *req)
253 struct sk_buff *skb = req->context, *skb2;
254 struct eth_dev *dev = ep->driver_data;
255 int status = req->status;
259 /* normal completion */
261 skb_put(skb, req->actual);
266 spin_lock_irqsave(&dev->lock, flags);
268 status = dev->unwrap(dev->port_usb,
272 dev_kfree_skb_any(skb);
275 spin_unlock_irqrestore(&dev->lock, flags);
277 skb_queue_tail(&dev->rx_frames, skb);
281 skb2 = skb_dequeue(&dev->rx_frames);
284 || ETH_HLEN > skb2->len
285 || skb2->len > GETHER_MAX_ETH_FRAME_LEN) {
286 dev->net->stats.rx_errors++;
287 dev->net->stats.rx_length_errors++;
288 DBG(dev, "rx length %d\n", skb2->len);
289 dev_kfree_skb_any(skb2);
292 skb2->protocol = eth_type_trans(skb2, dev->net);
293 dev->net->stats.rx_packets++;
294 dev->net->stats.rx_bytes += skb2->len;
296 /* no buffer copies needed, unless hardware can't
299 status = netif_rx(skb2);
301 skb2 = skb_dequeue(&dev->rx_frames);
305 /* software-driven interface shutdown */
306 case -ECONNRESET: /* unlink */
307 case -ESHUTDOWN: /* disconnect etc */
308 VDBG(dev, "rx shutdown, code %d\n", status);
311 /* for hardware automagic (such as pxa) */
312 case -ECONNABORTED: /* endpoint reset */
313 DBG(dev, "rx %s reset\n", ep->name);
314 defer_kevent(dev, WORK_RX_MEMORY);
316 dev_kfree_skb_any(skb);
321 dev->net->stats.rx_over_errors++;
325 dev->net->stats.rx_errors++;
326 DBG(dev, "rx status %d\n", status);
331 dev_kfree_skb_any(skb);
332 if (!netif_running(dev->net)) {
334 spin_lock(&dev->req_lock);
335 list_add(&req->list, &dev->rx_reqs);
336 spin_unlock(&dev->req_lock);
340 rx_submit(dev, req, GFP_ATOMIC);
343 static int prealloc(struct list_head *list, struct usb_ep *ep, unsigned n)
346 struct usb_request *req;
351 /* queue/recycle up to N requests */
353 list_for_each_entry(req, list, list) {
358 req = usb_ep_alloc_request(ep, GFP_ATOMIC);
360 return list_empty(list) ? -ENOMEM : 0;
361 list_add(&req->list, list);
368 struct list_head *next;
370 next = req->list.next;
371 list_del(&req->list);
372 usb_ep_free_request(ep, req);
377 req = container_of(next, struct usb_request, list);
382 static int alloc_requests(struct eth_dev *dev, struct gether *link, unsigned n)
386 spin_lock(&dev->req_lock);
387 status = prealloc(&dev->tx_reqs, link->in_ep, n);
390 status = prealloc(&dev->rx_reqs, link->out_ep, n);
395 DBG(dev, "can't alloc requests\n");
397 spin_unlock(&dev->req_lock);
401 static void rx_fill(struct eth_dev *dev, gfp_t gfp_flags)
403 struct usb_request *req;
406 /* fill unused rxq slots with some skb */
407 spin_lock_irqsave(&dev->req_lock, flags);
408 while (!list_empty(&dev->rx_reqs)) {
409 req = list_first_entry(&dev->rx_reqs, struct usb_request, list);
410 list_del_init(&req->list);
411 spin_unlock_irqrestore(&dev->req_lock, flags);
413 if (rx_submit(dev, req, gfp_flags) < 0) {
414 defer_kevent(dev, WORK_RX_MEMORY);
418 spin_lock_irqsave(&dev->req_lock, flags);
420 spin_unlock_irqrestore(&dev->req_lock, flags);
423 static void eth_work(struct work_struct *work)
425 struct eth_dev *dev = container_of(work, struct eth_dev, work);
427 if (test_and_clear_bit(WORK_RX_MEMORY, &dev->todo)) {
428 if (netif_running(dev->net))
429 rx_fill(dev, GFP_KERNEL);
433 DBG(dev, "work done, flags = 0x%lx\n", dev->todo);
436 static void tx_complete(struct usb_ep *ep, struct usb_request *req)
438 struct sk_buff *skb = req->context;
439 struct eth_dev *dev = ep->driver_data;
441 switch (req->status) {
443 dev->net->stats.tx_errors++;
444 VDBG(dev, "tx err %d\n", req->status);
446 case -ECONNRESET: /* unlink */
447 case -ESHUTDOWN: /* disconnect etc */
448 dev_kfree_skb_any(skb);
451 dev->net->stats.tx_bytes += skb->len;
452 dev_consume_skb_any(skb);
454 dev->net->stats.tx_packets++;
456 spin_lock(&dev->req_lock);
457 list_add(&req->list, &dev->tx_reqs);
458 spin_unlock(&dev->req_lock);
460 atomic_dec(&dev->tx_qlen);
461 if (netif_carrier_ok(dev->net))
462 netif_wake_queue(dev->net);
465 static inline int is_promisc(u16 cdc_filter)
467 return cdc_filter & USB_CDC_PACKET_TYPE_PROMISCUOUS;
470 static netdev_tx_t eth_start_xmit(struct sk_buff *skb,
471 struct net_device *net)
473 struct eth_dev *dev = netdev_priv(net);
476 struct usb_request *req = NULL;
481 spin_lock_irqsave(&dev->lock, flags);
483 in = dev->port_usb->in_ep;
484 cdc_filter = dev->port_usb->cdc_filter;
489 spin_unlock_irqrestore(&dev->lock, flags);
492 dev_kfree_skb_any(skb);
496 /* apply outgoing CDC or RNDIS filters */
497 if (skb && !is_promisc(cdc_filter)) {
498 u8 *dest = skb->data;
500 if (is_multicast_ether_addr(dest)) {
503 /* ignores USB_CDC_PACKET_TYPE_MULTICAST and host
504 * SET_ETHERNET_MULTICAST_FILTERS requests
506 if (is_broadcast_ether_addr(dest))
507 type = USB_CDC_PACKET_TYPE_BROADCAST;
509 type = USB_CDC_PACKET_TYPE_ALL_MULTICAST;
510 if (!(cdc_filter & type)) {
511 dev_kfree_skb_any(skb);
515 /* ignores USB_CDC_PACKET_TYPE_DIRECTED */
518 spin_lock_irqsave(&dev->req_lock, flags);
520 * this freelist can be empty if an interrupt triggered disconnect()
521 * and reconfigured the gadget (shutting down this queue) after the
522 * network stack decided to xmit but before we got the spinlock.
524 if (list_empty(&dev->tx_reqs)) {
525 spin_unlock_irqrestore(&dev->req_lock, flags);
526 return NETDEV_TX_BUSY;
529 req = list_first_entry(&dev->tx_reqs, struct usb_request, list);
530 list_del(&req->list);
532 /* temporarily stop TX queue when the freelist empties */
533 if (list_empty(&dev->tx_reqs))
534 netif_stop_queue(net);
535 spin_unlock_irqrestore(&dev->req_lock, flags);
537 /* no buffer copies needed, unless the network stack did it
538 * or the hardware can't use skb buffers.
539 * or there's not enough space for extra headers we need
544 spin_lock_irqsave(&dev->lock, flags);
546 skb = dev->wrap(dev->port_usb, skb);
547 spin_unlock_irqrestore(&dev->lock, flags);
549 /* Multi frame CDC protocols may store the frame for
550 * later which is not a dropped frame.
553 dev->port_usb->supports_multi_frame)
560 req->buf = skb->data;
562 req->complete = tx_complete;
564 /* NCM requires no zlp if transfer is dwNtbInMaxSize */
566 dev->port_usb->is_fixed &&
567 length == dev->port_usb->fixed_in_len &&
568 (length % in->maxpacket) == 0)
573 /* use zlp framing on tx for strict CDC-Ether conformance,
574 * though any robust network rx path ignores extra padding.
575 * and some hardware doesn't like to write zlps.
577 if (req->zero && !dev->zlp && (length % in->maxpacket) == 0)
580 req->length = length;
582 retval = usb_ep_queue(in, req, GFP_ATOMIC);
585 DBG(dev, "tx queue err %d\n", retval);
588 netif_trans_update(net);
589 atomic_inc(&dev->tx_qlen);
593 dev_kfree_skb_any(skb);
595 dev->net->stats.tx_dropped++;
597 spin_lock_irqsave(&dev->req_lock, flags);
598 if (list_empty(&dev->tx_reqs))
599 netif_start_queue(net);
600 list_add(&req->list, &dev->tx_reqs);
601 spin_unlock_irqrestore(&dev->req_lock, flags);
606 /*-------------------------------------------------------------------------*/
608 static void eth_start(struct eth_dev *dev, gfp_t gfp_flags)
610 DBG(dev, "%s\n", __func__);
612 /* fill the rx queue */
613 rx_fill(dev, gfp_flags);
615 /* and open the tx floodgates */
616 atomic_set(&dev->tx_qlen, 0);
617 netif_wake_queue(dev->net);
620 static int eth_open(struct net_device *net)
622 struct eth_dev *dev = netdev_priv(net);
625 DBG(dev, "%s\n", __func__);
626 if (netif_carrier_ok(dev->net))
627 eth_start(dev, GFP_KERNEL);
629 spin_lock_irq(&dev->lock);
630 link = dev->port_usb;
631 if (link && link->open)
633 spin_unlock_irq(&dev->lock);
638 static int eth_stop(struct net_device *net)
640 struct eth_dev *dev = netdev_priv(net);
643 VDBG(dev, "%s\n", __func__);
644 netif_stop_queue(net);
646 DBG(dev, "stop stats: rx/tx %ld/%ld, errs %ld/%ld\n",
647 dev->net->stats.rx_packets, dev->net->stats.tx_packets,
648 dev->net->stats.rx_errors, dev->net->stats.tx_errors
651 /* ensure there are no more active requests */
652 spin_lock_irqsave(&dev->lock, flags);
654 struct gether *link = dev->port_usb;
655 const struct usb_endpoint_descriptor *in;
656 const struct usb_endpoint_descriptor *out;
661 /* NOTE: we have no abort-queue primitive we could use
662 * to cancel all pending I/O. Instead, we disable then
663 * reenable the endpoints ... this idiom may leave toggle
664 * wrong, but that's a self-correcting error.
666 * REVISIT: we *COULD* just let the transfers complete at
667 * their own pace; the network stack can handle old packets.
668 * For the moment we leave this here, since it works.
670 in = link->in_ep->desc;
671 out = link->out_ep->desc;
672 usb_ep_disable(link->in_ep);
673 usb_ep_disable(link->out_ep);
674 if (netif_carrier_ok(net)) {
675 DBG(dev, "host still using in/out endpoints\n");
676 link->in_ep->desc = in;
677 link->out_ep->desc = out;
678 usb_ep_enable(link->in_ep);
679 usb_ep_enable(link->out_ep);
682 spin_unlock_irqrestore(&dev->lock, flags);
687 /*-------------------------------------------------------------------------*/
689 static int get_ether_addr(const char *str, u8 *dev_addr)
694 for (i = 0; i < 6; i++) {
697 if ((*str == '.') || (*str == ':'))
699 num = hex_to_bin(*str++) << 4;
700 num |= hex_to_bin(*str++);
703 if (is_valid_ether_addr(dev_addr))
706 eth_random_addr(dev_addr);
710 static int get_ether_addr_str(u8 dev_addr[ETH_ALEN], char *str, int len)
715 snprintf(str, len, "%pM", dev_addr);
719 static const struct net_device_ops eth_netdev_ops = {
720 .ndo_open = eth_open,
721 .ndo_stop = eth_stop,
722 .ndo_start_xmit = eth_start_xmit,
723 .ndo_set_mac_address = eth_mac_addr,
724 .ndo_validate_addr = eth_validate_addr,
727 static struct device_type gadget_type = {
732 * gether_setup_name - initialize one ethernet-over-usb link
733 * @g: gadget to associated with these links
734 * @ethaddr: NULL, or a buffer in which the ethernet address of the
735 * host side of the link is recorded
736 * @netname: name for network device (for example, "usb")
739 * This sets up the single network link that may be exported by a
740 * gadget driver using this framework. The link layer addresses are
741 * set up using module parameters.
743 * Returns an eth_dev pointer on success, or an ERR_PTR on failure.
745 struct eth_dev *gether_setup_name(struct usb_gadget *g,
746 const char *dev_addr, const char *host_addr,
747 u8 ethaddr[ETH_ALEN], unsigned qmult, const char *netname)
750 struct net_device *net;
753 net = alloc_etherdev(sizeof *dev);
755 return ERR_PTR(-ENOMEM);
757 dev = netdev_priv(net);
758 spin_lock_init(&dev->lock);
759 spin_lock_init(&dev->req_lock);
760 INIT_WORK(&dev->work, eth_work);
761 INIT_LIST_HEAD(&dev->tx_reqs);
762 INIT_LIST_HEAD(&dev->rx_reqs);
764 skb_queue_head_init(&dev->rx_frames);
766 /* network device setup */
769 snprintf(net->name, sizeof(net->name), "%s%%d", netname);
771 if (get_ether_addr(dev_addr, net->dev_addr))
773 "using random %s ethernet address\n", "self");
774 if (get_ether_addr(host_addr, dev->host_mac))
776 "using random %s ethernet address\n", "host");
779 memcpy(ethaddr, dev->host_mac, ETH_ALEN);
781 net->netdev_ops = ð_netdev_ops;
783 net->ethtool_ops = &ops;
785 /* MTU range: 14 - 15412 */
786 net->min_mtu = ETH_HLEN;
787 net->max_mtu = GETHER_MAX_ETH_FRAME_LEN;
790 SET_NETDEV_DEV(net, &g->dev);
791 SET_NETDEV_DEVTYPE(net, &gadget_type);
793 status = register_netdev(net);
795 dev_dbg(&g->dev, "register_netdev failed, %d\n", status);
797 dev = ERR_PTR(status);
799 INFO(dev, "MAC %pM\n", net->dev_addr);
800 INFO(dev, "HOST MAC %pM\n", dev->host_mac);
803 * two kinds of host-initiated state changes:
804 * - iff DATA transfer is active, carrier is "on"
805 * - tx queueing enabled if open *and* carrier is "on"
807 netif_carrier_off(net);
812 EXPORT_SYMBOL_GPL(gether_setup_name);
814 struct net_device *gether_setup_name_default(const char *netname)
816 struct net_device *net;
819 net = alloc_etherdev(sizeof(*dev));
821 return ERR_PTR(-ENOMEM);
823 dev = netdev_priv(net);
824 spin_lock_init(&dev->lock);
825 spin_lock_init(&dev->req_lock);
826 INIT_WORK(&dev->work, eth_work);
827 INIT_LIST_HEAD(&dev->tx_reqs);
828 INIT_LIST_HEAD(&dev->rx_reqs);
830 skb_queue_head_init(&dev->rx_frames);
832 /* network device setup */
834 dev->qmult = QMULT_DEFAULT;
835 snprintf(net->name, sizeof(net->name), "%s%%d", netname);
837 eth_random_addr(dev->dev_mac);
838 pr_warn("using random %s ethernet address\n", "self");
839 eth_random_addr(dev->host_mac);
840 pr_warn("using random %s ethernet address\n", "host");
842 net->netdev_ops = ð_netdev_ops;
844 net->ethtool_ops = &ops;
845 SET_NETDEV_DEVTYPE(net, &gadget_type);
847 /* MTU range: 14 - 15412 */
848 net->min_mtu = ETH_HLEN;
849 net->max_mtu = GETHER_MAX_ETH_FRAME_LEN;
853 EXPORT_SYMBOL_GPL(gether_setup_name_default);
855 int gether_register_netdev(struct net_device *net)
858 struct usb_gadget *g;
862 if (!net->dev.parent)
864 dev = netdev_priv(net);
866 status = register_netdev(net);
868 dev_dbg(&g->dev, "register_netdev failed, %d\n", status);
871 INFO(dev, "HOST MAC %pM\n", dev->host_mac);
873 /* two kinds of host-initiated state changes:
874 * - iff DATA transfer is active, carrier is "on"
875 * - tx queueing enabled if open *and* carrier is "on"
877 netif_carrier_off(net);
879 sa.sa_family = net->type;
880 memcpy(sa.sa_data, dev->dev_mac, ETH_ALEN);
882 status = dev_set_mac_address(net, &sa);
885 pr_warn("cannot set self ethernet address: %d\n", status);
887 INFO(dev, "MAC %pM\n", dev->dev_mac);
891 EXPORT_SYMBOL_GPL(gether_register_netdev);
893 void gether_set_gadget(struct net_device *net, struct usb_gadget *g)
897 dev = netdev_priv(net);
899 SET_NETDEV_DEV(net, &g->dev);
901 EXPORT_SYMBOL_GPL(gether_set_gadget);
903 int gether_set_dev_addr(struct net_device *net, const char *dev_addr)
906 u8 new_addr[ETH_ALEN];
908 dev = netdev_priv(net);
909 if (get_ether_addr(dev_addr, new_addr))
911 memcpy(dev->dev_mac, new_addr, ETH_ALEN);
914 EXPORT_SYMBOL_GPL(gether_set_dev_addr);
916 int gether_get_dev_addr(struct net_device *net, char *dev_addr, int len)
921 dev = netdev_priv(net);
922 ret = get_ether_addr_str(dev->dev_mac, dev_addr, len);
924 dev_addr[ret++] = '\n';
925 dev_addr[ret] = '\0';
930 EXPORT_SYMBOL_GPL(gether_get_dev_addr);
932 int gether_set_host_addr(struct net_device *net, const char *host_addr)
935 u8 new_addr[ETH_ALEN];
937 dev = netdev_priv(net);
938 if (get_ether_addr(host_addr, new_addr))
940 memcpy(dev->host_mac, new_addr, ETH_ALEN);
943 EXPORT_SYMBOL_GPL(gether_set_host_addr);
945 int gether_get_host_addr(struct net_device *net, char *host_addr, int len)
950 dev = netdev_priv(net);
951 ret = get_ether_addr_str(dev->host_mac, host_addr, len);
953 host_addr[ret++] = '\n';
954 host_addr[ret] = '\0';
959 EXPORT_SYMBOL_GPL(gether_get_host_addr);
961 int gether_get_host_addr_cdc(struct net_device *net, char *host_addr, int len)
968 dev = netdev_priv(net);
969 snprintf(host_addr, len, "%pm", dev->host_mac);
971 return strlen(host_addr);
973 EXPORT_SYMBOL_GPL(gether_get_host_addr_cdc);
975 void gether_get_host_addr_u8(struct net_device *net, u8 host_mac[ETH_ALEN])
979 dev = netdev_priv(net);
980 memcpy(host_mac, dev->host_mac, ETH_ALEN);
982 EXPORT_SYMBOL_GPL(gether_get_host_addr_u8);
984 void gether_set_qmult(struct net_device *net, unsigned qmult)
988 dev = netdev_priv(net);
991 EXPORT_SYMBOL_GPL(gether_set_qmult);
993 unsigned gether_get_qmult(struct net_device *net)
997 dev = netdev_priv(net);
1000 EXPORT_SYMBOL_GPL(gether_get_qmult);
1002 int gether_get_ifname(struct net_device *net, char *name, int len)
1007 ret = snprintf(name, len, "%s\n", netdev_name(net));
1009 return ret < len ? ret : len;
1011 EXPORT_SYMBOL_GPL(gether_get_ifname);
1014 * gether_cleanup - remove Ethernet-over-USB device
1015 * Context: may sleep
1017 * This is called to free all resources allocated by @gether_setup().
1019 void gether_cleanup(struct eth_dev *dev)
1024 unregister_netdev(dev->net);
1025 flush_work(&dev->work);
1026 free_netdev(dev->net);
1028 EXPORT_SYMBOL_GPL(gether_cleanup);
1031 * gether_connect - notify network layer that USB link is active
1032 * @link: the USB link, set up with endpoints, descriptors matching
1033 * current device speed, and any framing wrapper(s) set up.
1034 * Context: irqs blocked
1036 * This is called to activate endpoints and let the network layer know
1037 * the connection is active ("carrier detect"). It may cause the I/O
1038 * queues to open and start letting network packets flow, but will in
1039 * any case activate the endpoints so that they respond properly to the
1042 * Verify net_device pointer returned using IS_ERR(). If it doesn't
1043 * indicate some error code (negative errno), ep->driver_data values
1044 * have been overwritten.
1046 struct net_device *gether_connect(struct gether *link)
1048 struct eth_dev *dev = link->ioport;
1052 return ERR_PTR(-EINVAL);
1054 link->in_ep->driver_data = dev;
1055 result = usb_ep_enable(link->in_ep);
1057 DBG(dev, "enable %s --> %d\n",
1058 link->in_ep->name, result);
1062 link->out_ep->driver_data = dev;
1063 result = usb_ep_enable(link->out_ep);
1065 DBG(dev, "enable %s --> %d\n",
1066 link->out_ep->name, result);
1071 result = alloc_requests(dev, link, qlen(dev->gadget,
1075 dev->zlp = link->is_zlp_ok;
1076 dev->no_skb_reserve = gadget_avoids_skb_reserve(dev->gadget);
1077 DBG(dev, "qlen %d\n", qlen(dev->gadget, dev->qmult));
1079 dev->header_len = link->header_len;
1080 dev->unwrap = link->unwrap;
1081 dev->wrap = link->wrap;
1083 spin_lock(&dev->lock);
1084 dev->port_usb = link;
1085 if (netif_running(dev->net)) {
1092 spin_unlock(&dev->lock);
1094 netif_carrier_on(dev->net);
1095 if (netif_running(dev->net))
1096 eth_start(dev, GFP_ATOMIC);
1098 /* on error, disable any endpoints */
1100 (void) usb_ep_disable(link->out_ep);
1102 (void) usb_ep_disable(link->in_ep);
1105 /* caller is responsible for cleanup on error */
1107 return ERR_PTR(result);
1110 EXPORT_SYMBOL_GPL(gether_connect);
1113 * gether_disconnect - notify network layer that USB link is inactive
1114 * @link: the USB link, on which gether_connect() was called
1115 * Context: irqs blocked
1117 * This is called to deactivate endpoints and let the network layer know
1118 * the connection went inactive ("no carrier").
1120 * On return, the state is as if gether_connect() had never been called.
1121 * The endpoints are inactive, and accordingly without active USB I/O.
1122 * Pointers to endpoint descriptors and endpoint private data are nulled.
1124 void gether_disconnect(struct gether *link)
1126 struct eth_dev *dev = link->ioport;
1127 struct usb_request *req;
1133 DBG(dev, "%s\n", __func__);
1135 netif_stop_queue(dev->net);
1136 netif_carrier_off(dev->net);
1138 /* disable endpoints, forcing (synchronous) completion
1139 * of all pending i/o. then free the request objects
1140 * and forget about the endpoints.
1142 usb_ep_disable(link->in_ep);
1143 spin_lock(&dev->req_lock);
1144 while (!list_empty(&dev->tx_reqs)) {
1145 req = list_first_entry(&dev->tx_reqs, struct usb_request, list);
1146 list_del(&req->list);
1148 spin_unlock(&dev->req_lock);
1149 usb_ep_free_request(link->in_ep, req);
1150 spin_lock(&dev->req_lock);
1152 spin_unlock(&dev->req_lock);
1153 link->in_ep->desc = NULL;
1155 usb_ep_disable(link->out_ep);
1156 spin_lock(&dev->req_lock);
1157 while (!list_empty(&dev->rx_reqs)) {
1158 req = list_first_entry(&dev->rx_reqs, struct usb_request, list);
1159 list_del(&req->list);
1161 spin_unlock(&dev->req_lock);
1162 usb_ep_free_request(link->out_ep, req);
1163 spin_lock(&dev->req_lock);
1165 spin_unlock(&dev->req_lock);
1166 link->out_ep->desc = NULL;
1168 /* finish forgetting about this USB link episode */
1169 dev->header_len = 0;
1173 spin_lock(&dev->lock);
1174 dev->port_usb = NULL;
1175 spin_unlock(&dev->lock);
1177 EXPORT_SYMBOL_GPL(gether_disconnect);
1179 MODULE_LICENSE("GPL");
1180 MODULE_AUTHOR("David Brownell");