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 MTU size to 15k+52 to prevent allocating 32k
49 * blocks and still have efficient handling. */
50 #define GETHER_MAX_MTU_SIZE 15412
51 #define GETHER_MAX_ETH_FRAME_LEN (GETHER_MAX_MTU_SIZE + ETH_HLEN)
54 /* lock is held while accessing port_usb
57 struct gether *port_usb;
59 struct net_device *net;
60 struct usb_gadget *gadget;
62 spinlock_t req_lock; /* guard {rx,tx}_reqs */
63 struct list_head tx_reqs, rx_reqs;
66 struct sk_buff_head rx_frames;
71 struct sk_buff *(*wrap)(struct gether *, struct sk_buff *skb);
72 int (*unwrap)(struct gether *,
74 struct sk_buff_head *list);
76 struct work_struct work;
79 #define WORK_RX_MEMORY 0
83 u8 host_mac[ETH_ALEN];
87 /*-------------------------------------------------------------------------*/
89 #define RX_EXTRA 20 /* bytes guarding against rx overflows */
91 #define DEFAULT_QLEN 2 /* double buffering by default */
93 /* for dual-speed hardware, use deeper queues at high/super speed */
94 static inline int qlen(struct usb_gadget *gadget, unsigned qmult)
96 if (gadget_is_dualspeed(gadget) && (gadget->speed == USB_SPEED_HIGH ||
97 gadget->speed >= USB_SPEED_SUPER))
98 return qmult * DEFAULT_QLEN;
103 /*-------------------------------------------------------------------------*/
105 /* REVISIT there must be a better way than having two sets
114 #define xprintk(d, level, fmt, args...) \
115 printk(level "%s: " fmt , (d)->net->name , ## args)
119 #define DBG(dev, fmt, args...) \
120 xprintk(dev , KERN_DEBUG , fmt , ## args)
122 #define DBG(dev, fmt, args...) \
129 #define VDBG(dev, fmt, args...) \
133 #define ERROR(dev, fmt, args...) \
134 xprintk(dev , KERN_ERR , fmt , ## args)
135 #define INFO(dev, fmt, args...) \
136 xprintk(dev , KERN_INFO , fmt , ## args)
138 /*-------------------------------------------------------------------------*/
140 /* NETWORK DRIVER HOOKUP (to the layer above this driver) */
142 static void eth_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *p)
144 struct eth_dev *dev = netdev_priv(net);
146 strlcpy(p->driver, "g_ether", sizeof(p->driver));
147 strlcpy(p->version, UETH__VERSION, sizeof(p->version));
148 strlcpy(p->fw_version, dev->gadget->name, sizeof(p->fw_version));
149 strlcpy(p->bus_info, dev_name(&dev->gadget->dev), sizeof(p->bus_info));
152 /* REVISIT can also support:
153 * - WOL (by tracking suspends and issuing remote wakeup)
154 * - msglevel (implies updated messaging)
155 * - ... probably more ethtool ops
158 static const struct ethtool_ops ops = {
159 .get_drvinfo = eth_get_drvinfo,
160 .get_link = ethtool_op_get_link,
163 static void defer_kevent(struct eth_dev *dev, int flag)
165 if (test_and_set_bit(flag, &dev->todo))
167 if (!schedule_work(&dev->work))
168 ERROR(dev, "kevent %d may have been dropped\n", flag);
170 DBG(dev, "kevent %d scheduled\n", flag);
173 static void rx_complete(struct usb_ep *ep, struct usb_request *req);
176 rx_submit(struct eth_dev *dev, struct usb_request *req, gfp_t gfp_flags)
178 struct usb_gadget *g = dev->gadget;
180 int retval = -ENOMEM;
185 spin_lock_irqsave(&dev->lock, flags);
187 out = dev->port_usb->out_ep;
193 spin_unlock_irqrestore(&dev->lock, flags);
197 /* Padding up to RX_EXTRA handles minor disagreements with host.
198 * Normally we use the USB "terminate on short read" convention;
199 * so allow up to (N*maxpacket), since that memory is normally
200 * already allocated. Some hardware doesn't deal well with short
201 * reads (e.g. DMA must be N*maxpacket), so for now don't trim a
202 * byte off the end (to force hardware errors on overflow).
204 * RNDIS uses internal framing, and explicitly allows senders to
205 * pad to end-of-packet. That's potentially nice for speed, but
206 * means receivers can't recover lost synch on their own (because
207 * new packets don't only start after a short RX).
209 size += sizeof(struct ethhdr) + dev->net->mtu + RX_EXTRA;
210 size += dev->port_usb->header_len;
212 if (g->quirk_ep_out_aligned_size) {
213 size += out->maxpacket - 1;
214 size -= size % out->maxpacket;
217 if (dev->port_usb->is_fixed)
218 size = max_t(size_t, size, dev->port_usb->fixed_out_len);
219 spin_unlock_irqrestore(&dev->lock, flags);
221 skb = __netdev_alloc_skb(dev->net, size + NET_IP_ALIGN, gfp_flags);
223 DBG(dev, "no rx skb\n");
227 /* Some platforms perform better when IP packets are aligned,
228 * but on at least one, checksumming fails otherwise. Note:
229 * RNDIS headers involve variable numbers of LE32 values.
231 if (likely(!dev->no_skb_reserve))
232 skb_reserve(skb, NET_IP_ALIGN);
234 req->buf = skb->data;
236 req->complete = rx_complete;
239 retval = usb_ep_queue(out, req, gfp_flags);
240 if (retval == -ENOMEM)
242 defer_kevent(dev, WORK_RX_MEMORY);
244 DBG(dev, "rx submit --> %d\n", retval);
246 dev_kfree_skb_any(skb);
247 spin_lock_irqsave(&dev->req_lock, flags);
248 list_add(&req->list, &dev->rx_reqs);
249 spin_unlock_irqrestore(&dev->req_lock, flags);
254 static void rx_complete(struct usb_ep *ep, struct usb_request *req)
256 struct sk_buff *skb = req->context, *skb2;
257 struct eth_dev *dev = ep->driver_data;
258 int status = req->status;
262 /* normal completion */
264 skb_put(skb, req->actual);
269 spin_lock_irqsave(&dev->lock, flags);
271 status = dev->unwrap(dev->port_usb,
275 dev_kfree_skb_any(skb);
278 spin_unlock_irqrestore(&dev->lock, flags);
280 skb_queue_tail(&dev->rx_frames, skb);
284 skb2 = skb_dequeue(&dev->rx_frames);
287 || ETH_HLEN > skb2->len
288 || skb2->len > GETHER_MAX_ETH_FRAME_LEN) {
289 dev->net->stats.rx_errors++;
290 dev->net->stats.rx_length_errors++;
291 DBG(dev, "rx length %d\n", skb2->len);
292 dev_kfree_skb_any(skb2);
295 skb2->protocol = eth_type_trans(skb2, dev->net);
296 dev->net->stats.rx_packets++;
297 dev->net->stats.rx_bytes += skb2->len;
299 /* no buffer copies needed, unless hardware can't
302 status = netif_rx(skb2);
304 skb2 = skb_dequeue(&dev->rx_frames);
308 /* software-driven interface shutdown */
309 case -ECONNRESET: /* unlink */
310 case -ESHUTDOWN: /* disconnect etc */
311 VDBG(dev, "rx shutdown, code %d\n", status);
314 /* for hardware automagic (such as pxa) */
315 case -ECONNABORTED: /* endpoint reset */
316 DBG(dev, "rx %s reset\n", ep->name);
317 defer_kevent(dev, WORK_RX_MEMORY);
319 dev_kfree_skb_any(skb);
324 dev->net->stats.rx_over_errors++;
328 dev->net->stats.rx_errors++;
329 DBG(dev, "rx status %d\n", status);
334 dev_kfree_skb_any(skb);
335 if (!netif_running(dev->net)) {
337 spin_lock(&dev->req_lock);
338 list_add(&req->list, &dev->rx_reqs);
339 spin_unlock(&dev->req_lock);
343 rx_submit(dev, req, GFP_ATOMIC);
346 static int prealloc(struct list_head *list, struct usb_ep *ep, unsigned n)
349 struct usb_request *req;
354 /* queue/recycle up to N requests */
356 list_for_each_entry(req, list, list) {
361 req = usb_ep_alloc_request(ep, GFP_ATOMIC);
363 return list_empty(list) ? -ENOMEM : 0;
364 list_add(&req->list, list);
371 struct list_head *next;
373 next = req->list.next;
374 list_del(&req->list);
375 usb_ep_free_request(ep, req);
380 req = container_of(next, struct usb_request, list);
385 static int alloc_requests(struct eth_dev *dev, struct gether *link, unsigned n)
389 spin_lock(&dev->req_lock);
390 status = prealloc(&dev->tx_reqs, link->in_ep, n);
393 status = prealloc(&dev->rx_reqs, link->out_ep, n);
398 DBG(dev, "can't alloc requests\n");
400 spin_unlock(&dev->req_lock);
404 static void rx_fill(struct eth_dev *dev, gfp_t gfp_flags)
406 struct usb_request *req;
409 /* fill unused rxq slots with some skb */
410 spin_lock_irqsave(&dev->req_lock, flags);
411 while (!list_empty(&dev->rx_reqs)) {
412 req = list_first_entry(&dev->rx_reqs, struct usb_request, list);
413 list_del_init(&req->list);
414 spin_unlock_irqrestore(&dev->req_lock, flags);
416 if (rx_submit(dev, req, gfp_flags) < 0) {
417 defer_kevent(dev, WORK_RX_MEMORY);
421 spin_lock_irqsave(&dev->req_lock, flags);
423 spin_unlock_irqrestore(&dev->req_lock, flags);
426 static void eth_work(struct work_struct *work)
428 struct eth_dev *dev = container_of(work, struct eth_dev, work);
430 if (test_and_clear_bit(WORK_RX_MEMORY, &dev->todo)) {
431 if (netif_running(dev->net))
432 rx_fill(dev, GFP_KERNEL);
436 DBG(dev, "work done, flags = 0x%lx\n", dev->todo);
439 static void tx_complete(struct usb_ep *ep, struct usb_request *req)
441 struct sk_buff *skb = req->context;
442 struct eth_dev *dev = ep->driver_data;
444 switch (req->status) {
446 dev->net->stats.tx_errors++;
447 VDBG(dev, "tx err %d\n", req->status);
449 case -ECONNRESET: /* unlink */
450 case -ESHUTDOWN: /* disconnect etc */
451 dev_kfree_skb_any(skb);
454 dev->net->stats.tx_bytes += skb->len;
455 dev_consume_skb_any(skb);
457 dev->net->stats.tx_packets++;
459 spin_lock(&dev->req_lock);
460 list_add(&req->list, &dev->tx_reqs);
461 spin_unlock(&dev->req_lock);
463 atomic_dec(&dev->tx_qlen);
464 if (netif_carrier_ok(dev->net))
465 netif_wake_queue(dev->net);
468 static inline int is_promisc(u16 cdc_filter)
470 return cdc_filter & USB_CDC_PACKET_TYPE_PROMISCUOUS;
473 static netdev_tx_t eth_start_xmit(struct sk_buff *skb,
474 struct net_device *net)
476 struct eth_dev *dev = netdev_priv(net);
479 struct usb_request *req = NULL;
484 spin_lock_irqsave(&dev->lock, flags);
486 in = dev->port_usb->in_ep;
487 cdc_filter = dev->port_usb->cdc_filter;
492 spin_unlock_irqrestore(&dev->lock, flags);
496 dev_kfree_skb_any(skb);
500 /* apply outgoing CDC or RNDIS filters */
501 if (skb && !is_promisc(cdc_filter)) {
502 u8 *dest = skb->data;
504 if (is_multicast_ether_addr(dest)) {
507 /* ignores USB_CDC_PACKET_TYPE_MULTICAST and host
508 * SET_ETHERNET_MULTICAST_FILTERS requests
510 if (is_broadcast_ether_addr(dest))
511 type = USB_CDC_PACKET_TYPE_BROADCAST;
513 type = USB_CDC_PACKET_TYPE_ALL_MULTICAST;
514 if (!(cdc_filter & type)) {
515 dev_kfree_skb_any(skb);
519 /* ignores USB_CDC_PACKET_TYPE_DIRECTED */
522 spin_lock_irqsave(&dev->req_lock, flags);
524 * this freelist can be empty if an interrupt triggered disconnect()
525 * and reconfigured the gadget (shutting down this queue) after the
526 * network stack decided to xmit but before we got the spinlock.
528 if (list_empty(&dev->tx_reqs)) {
529 spin_unlock_irqrestore(&dev->req_lock, flags);
530 return NETDEV_TX_BUSY;
533 req = list_first_entry(&dev->tx_reqs, struct usb_request, list);
534 list_del(&req->list);
536 /* temporarily stop TX queue when the freelist empties */
537 if (list_empty(&dev->tx_reqs))
538 netif_stop_queue(net);
539 spin_unlock_irqrestore(&dev->req_lock, flags);
541 /* no buffer copies needed, unless the network stack did it
542 * or the hardware can't use skb buffers.
543 * or there's not enough space for extra headers we need
548 spin_lock_irqsave(&dev->lock, flags);
550 skb = dev->wrap(dev->port_usb, skb);
551 spin_unlock_irqrestore(&dev->lock, flags);
553 /* Multi frame CDC protocols may store the frame for
554 * later which is not a dropped frame.
557 dev->port_usb->supports_multi_frame)
564 req->buf = skb->data;
566 req->complete = tx_complete;
568 /* NCM requires no zlp if transfer is dwNtbInMaxSize */
570 dev->port_usb->is_fixed &&
571 length == dev->port_usb->fixed_in_len &&
572 (length % in->maxpacket) == 0)
577 /* use zlp framing on tx for strict CDC-Ether conformance,
578 * though any robust network rx path ignores extra padding.
579 * and some hardware doesn't like to write zlps.
581 if (req->zero && !dev->zlp && (length % in->maxpacket) == 0)
584 req->length = length;
586 retval = usb_ep_queue(in, req, GFP_ATOMIC);
589 DBG(dev, "tx queue err %d\n", retval);
592 netif_trans_update(net);
593 atomic_inc(&dev->tx_qlen);
597 dev_kfree_skb_any(skb);
599 dev->net->stats.tx_dropped++;
601 spin_lock_irqsave(&dev->req_lock, flags);
602 if (list_empty(&dev->tx_reqs))
603 netif_start_queue(net);
604 list_add(&req->list, &dev->tx_reqs);
605 spin_unlock_irqrestore(&dev->req_lock, flags);
610 /*-------------------------------------------------------------------------*/
612 static void eth_start(struct eth_dev *dev, gfp_t gfp_flags)
614 DBG(dev, "%s\n", __func__);
616 /* fill the rx queue */
617 rx_fill(dev, gfp_flags);
619 /* and open the tx floodgates */
620 atomic_set(&dev->tx_qlen, 0);
621 netif_wake_queue(dev->net);
624 static int eth_open(struct net_device *net)
626 struct eth_dev *dev = netdev_priv(net);
629 DBG(dev, "%s\n", __func__);
630 if (netif_carrier_ok(dev->net))
631 eth_start(dev, GFP_KERNEL);
633 spin_lock_irq(&dev->lock);
634 link = dev->port_usb;
635 if (link && link->open)
637 spin_unlock_irq(&dev->lock);
642 static int eth_stop(struct net_device *net)
644 struct eth_dev *dev = netdev_priv(net);
647 VDBG(dev, "%s\n", __func__);
648 netif_stop_queue(net);
650 DBG(dev, "stop stats: rx/tx %ld/%ld, errs %ld/%ld\n",
651 dev->net->stats.rx_packets, dev->net->stats.tx_packets,
652 dev->net->stats.rx_errors, dev->net->stats.tx_errors
655 /* ensure there are no more active requests */
656 spin_lock_irqsave(&dev->lock, flags);
658 struct gether *link = dev->port_usb;
659 const struct usb_endpoint_descriptor *in;
660 const struct usb_endpoint_descriptor *out;
665 /* NOTE: we have no abort-queue primitive we could use
666 * to cancel all pending I/O. Instead, we disable then
667 * reenable the endpoints ... this idiom may leave toggle
668 * wrong, but that's a self-correcting error.
670 * REVISIT: we *COULD* just let the transfers complete at
671 * their own pace; the network stack can handle old packets.
672 * For the moment we leave this here, since it works.
674 in = link->in_ep->desc;
675 out = link->out_ep->desc;
676 usb_ep_disable(link->in_ep);
677 usb_ep_disable(link->out_ep);
678 if (netif_carrier_ok(net)) {
679 DBG(dev, "host still using in/out endpoints\n");
680 link->in_ep->desc = in;
681 link->out_ep->desc = out;
682 usb_ep_enable(link->in_ep);
683 usb_ep_enable(link->out_ep);
686 spin_unlock_irqrestore(&dev->lock, flags);
691 /*-------------------------------------------------------------------------*/
693 static int get_ether_addr(const char *str, u8 *dev_addr)
698 for (i = 0; i < 6; i++) {
701 if ((*str == '.') || (*str == ':'))
703 num = hex_to_bin(*str++) << 4;
704 num |= hex_to_bin(*str++);
707 if (is_valid_ether_addr(dev_addr))
710 eth_random_addr(dev_addr);
714 static int get_ether_addr_str(u8 dev_addr[ETH_ALEN], char *str, int len)
719 snprintf(str, len, "%pM", dev_addr);
723 static const struct net_device_ops eth_netdev_ops = {
724 .ndo_open = eth_open,
725 .ndo_stop = eth_stop,
726 .ndo_start_xmit = eth_start_xmit,
727 .ndo_set_mac_address = eth_mac_addr,
728 .ndo_validate_addr = eth_validate_addr,
731 static struct device_type gadget_type = {
736 * gether_setup_name - initialize one ethernet-over-usb link
737 * @g: gadget to associated with these links
738 * @ethaddr: NULL, or a buffer in which the ethernet address of the
739 * host side of the link is recorded
740 * @netname: name for network device (for example, "usb")
743 * This sets up the single network link that may be exported by a
744 * gadget driver using this framework. The link layer addresses are
745 * set up using module parameters.
747 * Returns an eth_dev pointer on success, or an ERR_PTR on failure.
749 struct eth_dev *gether_setup_name(struct usb_gadget *g,
750 const char *dev_addr, const char *host_addr,
751 u8 ethaddr[ETH_ALEN], unsigned qmult, const char *netname)
754 struct net_device *net;
757 net = alloc_etherdev(sizeof *dev);
759 return ERR_PTR(-ENOMEM);
761 dev = netdev_priv(net);
762 spin_lock_init(&dev->lock);
763 spin_lock_init(&dev->req_lock);
764 INIT_WORK(&dev->work, eth_work);
765 INIT_LIST_HEAD(&dev->tx_reqs);
766 INIT_LIST_HEAD(&dev->rx_reqs);
768 skb_queue_head_init(&dev->rx_frames);
770 /* network device setup */
773 snprintf(net->name, sizeof(net->name), "%s%%d", netname);
775 if (get_ether_addr(dev_addr, net->dev_addr))
777 "using random %s ethernet address\n", "self");
778 if (get_ether_addr(host_addr, dev->host_mac))
780 "using random %s ethernet address\n", "host");
783 memcpy(ethaddr, dev->host_mac, ETH_ALEN);
785 net->netdev_ops = ð_netdev_ops;
787 net->ethtool_ops = &ops;
789 /* MTU range: 14 - 15412 */
790 net->min_mtu = ETH_HLEN;
791 net->max_mtu = GETHER_MAX_MTU_SIZE;
794 SET_NETDEV_DEV(net, &g->dev);
795 SET_NETDEV_DEVTYPE(net, &gadget_type);
797 status = register_netdev(net);
799 dev_dbg(&g->dev, "register_netdev failed, %d\n", status);
801 dev = ERR_PTR(status);
803 INFO(dev, "MAC %pM\n", net->dev_addr);
804 INFO(dev, "HOST MAC %pM\n", dev->host_mac);
807 * two kinds of host-initiated state changes:
808 * - iff DATA transfer is active, carrier is "on"
809 * - tx queueing enabled if open *and* carrier is "on"
811 netif_carrier_off(net);
816 EXPORT_SYMBOL_GPL(gether_setup_name);
818 struct net_device *gether_setup_name_default(const char *netname)
820 struct net_device *net;
823 net = alloc_etherdev(sizeof(*dev));
825 return ERR_PTR(-ENOMEM);
827 dev = netdev_priv(net);
828 spin_lock_init(&dev->lock);
829 spin_lock_init(&dev->req_lock);
830 INIT_WORK(&dev->work, eth_work);
831 INIT_LIST_HEAD(&dev->tx_reqs);
832 INIT_LIST_HEAD(&dev->rx_reqs);
834 skb_queue_head_init(&dev->rx_frames);
836 /* network device setup */
838 dev->qmult = QMULT_DEFAULT;
839 snprintf(net->name, sizeof(net->name), "%s%%d", netname);
841 eth_random_addr(dev->dev_mac);
842 pr_warn("using random %s ethernet address\n", "self");
843 eth_random_addr(dev->host_mac);
844 pr_warn("using random %s ethernet address\n", "host");
846 net->netdev_ops = ð_netdev_ops;
848 net->ethtool_ops = &ops;
849 SET_NETDEV_DEVTYPE(net, &gadget_type);
851 /* MTU range: 14 - 15412 */
852 net->min_mtu = ETH_HLEN;
853 net->max_mtu = GETHER_MAX_MTU_SIZE;
857 EXPORT_SYMBOL_GPL(gether_setup_name_default);
859 int gether_register_netdev(struct net_device *net)
862 struct usb_gadget *g;
866 if (!net->dev.parent)
868 dev = netdev_priv(net);
870 status = register_netdev(net);
872 dev_dbg(&g->dev, "register_netdev failed, %d\n", status);
875 INFO(dev, "HOST MAC %pM\n", dev->host_mac);
877 /* two kinds of host-initiated state changes:
878 * - iff DATA transfer is active, carrier is "on"
879 * - tx queueing enabled if open *and* carrier is "on"
881 netif_carrier_off(net);
883 sa.sa_family = net->type;
884 memcpy(sa.sa_data, dev->dev_mac, ETH_ALEN);
886 status = dev_set_mac_address(net, &sa);
889 pr_warn("cannot set self ethernet address: %d\n", status);
891 INFO(dev, "MAC %pM\n", dev->dev_mac);
895 EXPORT_SYMBOL_GPL(gether_register_netdev);
897 void gether_set_gadget(struct net_device *net, struct usb_gadget *g)
901 dev = netdev_priv(net);
903 SET_NETDEV_DEV(net, &g->dev);
905 EXPORT_SYMBOL_GPL(gether_set_gadget);
907 int gether_set_dev_addr(struct net_device *net, const char *dev_addr)
910 u8 new_addr[ETH_ALEN];
912 dev = netdev_priv(net);
913 if (get_ether_addr(dev_addr, new_addr))
915 memcpy(dev->dev_mac, new_addr, ETH_ALEN);
918 EXPORT_SYMBOL_GPL(gether_set_dev_addr);
920 int gether_get_dev_addr(struct net_device *net, char *dev_addr, int len)
925 dev = netdev_priv(net);
926 ret = get_ether_addr_str(dev->dev_mac, dev_addr, len);
928 dev_addr[ret++] = '\n';
929 dev_addr[ret] = '\0';
934 EXPORT_SYMBOL_GPL(gether_get_dev_addr);
936 int gether_set_host_addr(struct net_device *net, const char *host_addr)
939 u8 new_addr[ETH_ALEN];
941 dev = netdev_priv(net);
942 if (get_ether_addr(host_addr, new_addr))
944 memcpy(dev->host_mac, new_addr, ETH_ALEN);
947 EXPORT_SYMBOL_GPL(gether_set_host_addr);
949 int gether_get_host_addr(struct net_device *net, char *host_addr, int len)
954 dev = netdev_priv(net);
955 ret = get_ether_addr_str(dev->host_mac, host_addr, len);
957 host_addr[ret++] = '\n';
958 host_addr[ret] = '\0';
963 EXPORT_SYMBOL_GPL(gether_get_host_addr);
965 int gether_get_host_addr_cdc(struct net_device *net, char *host_addr, int len)
972 dev = netdev_priv(net);
973 snprintf(host_addr, len, "%pm", dev->host_mac);
975 return strlen(host_addr);
977 EXPORT_SYMBOL_GPL(gether_get_host_addr_cdc);
979 void gether_get_host_addr_u8(struct net_device *net, u8 host_mac[ETH_ALEN])
983 dev = netdev_priv(net);
984 memcpy(host_mac, dev->host_mac, ETH_ALEN);
986 EXPORT_SYMBOL_GPL(gether_get_host_addr_u8);
988 void gether_set_qmult(struct net_device *net, unsigned qmult)
992 dev = netdev_priv(net);
995 EXPORT_SYMBOL_GPL(gether_set_qmult);
997 unsigned gether_get_qmult(struct net_device *net)
1001 dev = netdev_priv(net);
1004 EXPORT_SYMBOL_GPL(gether_get_qmult);
1006 int gether_get_ifname(struct net_device *net, char *name, int len)
1011 ret = snprintf(name, len, "%s\n", netdev_name(net));
1013 return ret < len ? ret : len;
1015 EXPORT_SYMBOL_GPL(gether_get_ifname);
1018 * gether_cleanup - remove Ethernet-over-USB device
1019 * Context: may sleep
1021 * This is called to free all resources allocated by @gether_setup().
1023 void gether_cleanup(struct eth_dev *dev)
1028 unregister_netdev(dev->net);
1029 flush_work(&dev->work);
1030 free_netdev(dev->net);
1032 EXPORT_SYMBOL_GPL(gether_cleanup);
1035 * gether_connect - notify network layer that USB link is active
1036 * @link: the USB link, set up with endpoints, descriptors matching
1037 * current device speed, and any framing wrapper(s) set up.
1038 * Context: irqs blocked
1040 * This is called to activate endpoints and let the network layer know
1041 * the connection is active ("carrier detect"). It may cause the I/O
1042 * queues to open and start letting network packets flow, but will in
1043 * any case activate the endpoints so that they respond properly to the
1046 * Verify net_device pointer returned using IS_ERR(). If it doesn't
1047 * indicate some error code (negative errno), ep->driver_data values
1048 * have been overwritten.
1050 struct net_device *gether_connect(struct gether *link)
1052 struct eth_dev *dev = link->ioport;
1056 return ERR_PTR(-EINVAL);
1058 link->in_ep->driver_data = dev;
1059 result = usb_ep_enable(link->in_ep);
1061 DBG(dev, "enable %s --> %d\n",
1062 link->in_ep->name, result);
1066 link->out_ep->driver_data = dev;
1067 result = usb_ep_enable(link->out_ep);
1069 DBG(dev, "enable %s --> %d\n",
1070 link->out_ep->name, result);
1075 result = alloc_requests(dev, link, qlen(dev->gadget,
1079 dev->zlp = link->is_zlp_ok;
1080 dev->no_skb_reserve = gadget_avoids_skb_reserve(dev->gadget);
1081 DBG(dev, "qlen %d\n", qlen(dev->gadget, dev->qmult));
1083 dev->header_len = link->header_len;
1084 dev->unwrap = link->unwrap;
1085 dev->wrap = link->wrap;
1087 spin_lock(&dev->lock);
1088 dev->port_usb = link;
1089 if (netif_running(dev->net)) {
1096 spin_unlock(&dev->lock);
1098 netif_carrier_on(dev->net);
1099 if (netif_running(dev->net))
1100 eth_start(dev, GFP_ATOMIC);
1102 /* on error, disable any endpoints */
1104 (void) usb_ep_disable(link->out_ep);
1106 (void) usb_ep_disable(link->in_ep);
1109 /* caller is responsible for cleanup on error */
1111 return ERR_PTR(result);
1114 EXPORT_SYMBOL_GPL(gether_connect);
1117 * gether_disconnect - notify network layer that USB link is inactive
1118 * @link: the USB link, on which gether_connect() was called
1119 * Context: irqs blocked
1121 * This is called to deactivate endpoints and let the network layer know
1122 * the connection went inactive ("no carrier").
1124 * On return, the state is as if gether_connect() had never been called.
1125 * The endpoints are inactive, and accordingly without active USB I/O.
1126 * Pointers to endpoint descriptors and endpoint private data are nulled.
1128 void gether_disconnect(struct gether *link)
1130 struct eth_dev *dev = link->ioport;
1131 struct usb_request *req;
1137 DBG(dev, "%s\n", __func__);
1139 netif_stop_queue(dev->net);
1140 netif_carrier_off(dev->net);
1142 /* disable endpoints, forcing (synchronous) completion
1143 * of all pending i/o. then free the request objects
1144 * and forget about the endpoints.
1146 usb_ep_disable(link->in_ep);
1147 spin_lock(&dev->req_lock);
1148 while (!list_empty(&dev->tx_reqs)) {
1149 req = list_first_entry(&dev->tx_reqs, struct usb_request, list);
1150 list_del(&req->list);
1152 spin_unlock(&dev->req_lock);
1153 usb_ep_free_request(link->in_ep, req);
1154 spin_lock(&dev->req_lock);
1156 spin_unlock(&dev->req_lock);
1157 link->in_ep->desc = NULL;
1159 usb_ep_disable(link->out_ep);
1160 spin_lock(&dev->req_lock);
1161 while (!list_empty(&dev->rx_reqs)) {
1162 req = list_first_entry(&dev->rx_reqs, struct usb_request, list);
1163 list_del(&req->list);
1165 spin_unlock(&dev->req_lock);
1166 usb_ep_free_request(link->out_ep, req);
1167 spin_lock(&dev->req_lock);
1169 spin_unlock(&dev->req_lock);
1170 link->out_ep->desc = NULL;
1172 /* finish forgetting about this USB link episode */
1173 dev->header_len = 0;
1177 spin_lock(&dev->lock);
1178 dev->port_usb = NULL;
1179 spin_unlock(&dev->lock);
1181 EXPORT_SYMBOL_GPL(gether_disconnect);
1183 MODULE_LICENSE("GPL");
1184 MODULE_AUTHOR("David Brownell");