f_phonet.c

  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * f_phonet.c -- USB CDC Phonet function
  4 *
  5 * Copyright (C) 2007-2008 Nokia Corporation. All rights reserved.
  6 *
  7 * Author: Rémi Denis-Courmont
  8 */
  9
 10#include <linux/mm.h>
 11#include <linux/slab.h>
 12#include <linux/kernel.h>
 13#include <linux/module.h>
 14#include <linux/device.h>
 15
 16#include <linux/netdevice.h>
 17#include <linux/if_ether.h>
 18#include <linux/if_phonet.h>
 19#include <linux/if_arp.h>
 20
 21#include <linux/usb/ch9.h>
 22#include <linux/usb/cdc.h>
 23#include <linux/usb/composite.h>
 24
 25#include "u_phonet.h"
 26#include "u_ether.h"
 27
 28#define PN_MEDIA_USB	0x1B
 29#define MAXPACKET	512
 30#if (PAGE_SIZE % MAXPACKET)
 31#error MAXPACKET must divide PAGE_SIZE!
 32#endif
 33
 34/*-------------------------------------------------------------------------*/
 35
 36struct phonet_port {
 37	struct f_phonet			*usb;
 38	spinlock_t			lock;
 39};
 40
 41struct f_phonet {
 42	struct usb_function		function;
 43	struct {
 44		struct sk_buff		*skb;
 45		spinlock_t		lock;
 46	} rx;
 47	struct net_device		*dev;
 48	struct usb_ep			*in_ep, *out_ep;
 49
 50	struct usb_request		*in_req;
 51	struct usb_request		*out_reqv[];
 52};
 53
 54static int phonet_rxq_size = 17;
 55
 56static inline struct f_phonet *func_to_pn(struct usb_function *f)
 57{
 58	return container_of(f, struct f_phonet, function);
 59}
 60
 61/*-------------------------------------------------------------------------*/
 62
 63#define USB_CDC_SUBCLASS_PHONET	0xfe
 64#define USB_CDC_PHONET_TYPE	0xab
 65
 66static struct usb_interface_descriptor
 67pn_control_intf_desc = {
 68	.bLength =		sizeof pn_control_intf_desc,
 69	.bDescriptorType =	USB_DT_INTERFACE,
 70
 71	/* .bInterfaceNumber =	DYNAMIC, */
 72	.bInterfaceClass =	USB_CLASS_COMM,
 73	.bInterfaceSubClass =	USB_CDC_SUBCLASS_PHONET,
 74};
 75
 76static const struct usb_cdc_header_desc
 77pn_header_desc = {
 78	.bLength =		sizeof pn_header_desc,
 79	.bDescriptorType =	USB_DT_CS_INTERFACE,
 80	.bDescriptorSubType =	USB_CDC_HEADER_TYPE,
 81	.bcdCDC =		cpu_to_le16(0x0110),
 82};
 83
 84static const struct usb_cdc_header_desc
 85pn_phonet_desc = {
 86	.bLength =		sizeof pn_phonet_desc,
 87	.bDescriptorType =	USB_DT_CS_INTERFACE,
 88	.bDescriptorSubType =	USB_CDC_PHONET_TYPE,
 89	.bcdCDC =		cpu_to_le16(0x1505), /* ??? */
 90};
 91
 92static struct usb_cdc_union_desc
 93pn_union_desc = {
 94	.bLength =		sizeof pn_union_desc,
 95	.bDescriptorType =	USB_DT_CS_INTERFACE,
 96	.bDescriptorSubType =	USB_CDC_UNION_TYPE,
 97
 98	/* .bMasterInterface0 =	DYNAMIC, */
 99	/* .bSlaveInterface0 =	DYNAMIC, */
100};
101
102static struct usb_interface_descriptor
103pn_data_nop_intf_desc = {
104	.bLength =		sizeof pn_data_nop_intf_desc,
105	.bDescriptorType =	USB_DT_INTERFACE,
106
107	/* .bInterfaceNumber =	DYNAMIC, */
108	.bAlternateSetting =	0,
109	.bNumEndpoints =	0,
110	.bInterfaceClass =	USB_CLASS_CDC_DATA,
111};
112
113static struct usb_interface_descriptor
114pn_data_intf_desc = {
115	.bLength =		sizeof pn_data_intf_desc,
116	.bDescriptorType =	USB_DT_INTERFACE,
117
118	/* .bInterfaceNumber =	DYNAMIC, */
119	.bAlternateSetting =	1,
120	.bNumEndpoints =	2,
121	.bInterfaceClass =	USB_CLASS_CDC_DATA,
122};
123
124static struct usb_endpoint_descriptor
125pn_fs_sink_desc = {
126	.bLength =		USB_DT_ENDPOINT_SIZE,
127	.bDescriptorType =	USB_DT_ENDPOINT,
128
129	.bEndpointAddress =	USB_DIR_OUT,
130	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
131};
132
133static struct usb_endpoint_descriptor
134pn_hs_sink_desc = {
135	.bLength =		USB_DT_ENDPOINT_SIZE,
136	.bDescriptorType =	USB_DT_ENDPOINT,
137
138	.bEndpointAddress =	USB_DIR_OUT,
139	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
140	.wMaxPacketSize =	cpu_to_le16(MAXPACKET),
141};
142
143static struct usb_endpoint_descriptor
144pn_fs_source_desc = {
145	.bLength =		USB_DT_ENDPOINT_SIZE,
146	.bDescriptorType =	USB_DT_ENDPOINT,
147
148	.bEndpointAddress =	USB_DIR_IN,
149	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
150};
151
152static struct usb_endpoint_descriptor
153pn_hs_source_desc = {
154	.bLength =		USB_DT_ENDPOINT_SIZE,
155	.bDescriptorType =	USB_DT_ENDPOINT,
156
157	.bEndpointAddress =	USB_DIR_IN,
158	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
159	.wMaxPacketSize =	cpu_to_le16(512),
160};
161
162static struct usb_descriptor_header *fs_pn_function[] = {
163	(struct usb_descriptor_header *) &pn_control_intf_desc,
164	(struct usb_descriptor_header *) &pn_header_desc,
165	(struct usb_descriptor_header *) &pn_phonet_desc,
166	(struct usb_descriptor_header *) &pn_union_desc,
167	(struct usb_descriptor_header *) &pn_data_nop_intf_desc,
168	(struct usb_descriptor_header *) &pn_data_intf_desc,
169	(struct usb_descriptor_header *) &pn_fs_sink_desc,
170	(struct usb_descriptor_header *) &pn_fs_source_desc,
171	NULL,
172};
173
174static struct usb_descriptor_header *hs_pn_function[] = {
175	(struct usb_descriptor_header *) &pn_control_intf_desc,
176	(struct usb_descriptor_header *) &pn_header_desc,
177	(struct usb_descriptor_header *) &pn_phonet_desc,
178	(struct usb_descriptor_header *) &pn_union_desc,
179	(struct usb_descriptor_header *) &pn_data_nop_intf_desc,
180	(struct usb_descriptor_header *) &pn_data_intf_desc,
181	(struct usb_descriptor_header *) &pn_hs_sink_desc,
182	(struct usb_descriptor_header *) &pn_hs_source_desc,
183	NULL,
184};
185
186/*-------------------------------------------------------------------------*/
187
188static int pn_net_open(struct net_device *dev)
189{
190	netif_wake_queue(dev);
191	return 0;
192}
193
194static int pn_net_close(struct net_device *dev)
195{
196	netif_stop_queue(dev);
197	return 0;
198}
199
200static void pn_tx_complete(struct usb_ep *ep, struct usb_request *req)
201{
202	struct f_phonet *fp = ep->driver_data;
203	struct net_device *dev = fp->dev;
204	struct sk_buff *skb = req->context;
205
206	switch (req->status) {
207	case 0:
208		dev->stats.tx_packets++;
209		dev->stats.tx_bytes += skb->len;
210		break;
211
212	case -ESHUTDOWN: /* disconnected */
213	case -ECONNRESET: /* disabled */
214		dev->stats.tx_aborted_errors++;
215		fallthrough;
216	default:
217		dev->stats.tx_errors++;
218	}
219
220	dev_kfree_skb_any(skb);
221	netif_wake_queue(dev);
222}
223
224static netdev_tx_t pn_net_xmit(struct sk_buff *skb, struct net_device *dev)
225{
226	struct phonet_port *port = netdev_priv(dev);
227	struct f_phonet *fp;
228	struct usb_request *req;
229	unsigned long flags;
230
231	if (skb->protocol != htons(ETH_P_PHONET))
232		goto out;
233
234	spin_lock_irqsave(&port->lock, flags);
235	fp = port->usb;
236	if (unlikely(!fp)) /* race with carrier loss */
237		goto out_unlock;
238
239	req = fp->in_req;
240	req->buf = skb->data;
241	req->length = skb->len;
242	req->complete = pn_tx_complete;
243	req->zero = 1;
244	req->context = skb;
245
246	if (unlikely(usb_ep_queue(fp->in_ep, req, GFP_ATOMIC)))
247		goto out_unlock;
248
249	netif_stop_queue(dev);
250	skb = NULL;
251
252out_unlock:
253	spin_unlock_irqrestore(&port->lock, flags);
254out:
255	if (unlikely(skb)) {
256		dev_kfree_skb(skb);
257		dev->stats.tx_dropped++;
258	}
259	return NETDEV_TX_OK;
260}
261
262static const struct net_device_ops pn_netdev_ops = {
263	.ndo_open	= pn_net_open,
264	.ndo_stop	= pn_net_close,
265	.ndo_start_xmit	= pn_net_xmit,
266};
267
268static void pn_net_setup(struct net_device *dev)
269{
270	const u8 addr = PN_MEDIA_USB;
271
272	dev->features		= 0;
273	dev->type		= ARPHRD_PHONET;
274	dev->flags		= IFF_POINTOPOINT | IFF_NOARP;
275	dev->mtu		= PHONET_DEV_MTU;
276	dev->min_mtu		= PHONET_MIN_MTU;
277	dev->max_mtu		= PHONET_MAX_MTU;
278	dev->hard_header_len	= 1;
279	dev->addr_len		= 1;
280	dev_addr_set(dev, &addr);
281
282	dev->tx_queue_len	= 1;
283
284	dev->netdev_ops		= &pn_netdev_ops;
285	dev->needs_free_netdev	= true;
286	dev->header_ops		= &phonet_header_ops;
287}
288
289/*-------------------------------------------------------------------------*/
290
291/*
292 * Queue buffer for data from the host
293 */
294static int
295pn_rx_submit(struct f_phonet *fp, struct usb_request *req, gfp_t gfp_flags)
296{
297	struct page *page;
298	int err;
299
300	page = __dev_alloc_page(gfp_flags | __GFP_NOMEMALLOC);
301	if (!page)
302		return -ENOMEM;
303
304	req->buf = page_address(page);
305	req->length = PAGE_SIZE;
306	req->context = page;
307
308	err = usb_ep_queue(fp->out_ep, req, gfp_flags);
309	if (unlikely(err))
310		put_page(page);
311	return err;
312}
313
314static void pn_rx_complete(struct usb_ep *ep, struct usb_request *req)
315{
316	struct f_phonet *fp = ep->driver_data;
317	struct net_device *dev = fp->dev;
318	struct page *page = req->context;
319	struct sk_buff *skb;
320	unsigned long flags;
321	int status = req->status;
322
323	switch (status) {
324	case 0:
325		spin_lock_irqsave(&fp->rx.lock, flags);
326		skb = fp->rx.skb;
327		if (!skb)
328			skb = fp->rx.skb = netdev_alloc_skb(dev, 12);
329		if (req->actual < req->length) /* Last fragment */
330			fp->rx.skb = NULL;
331		spin_unlock_irqrestore(&fp->rx.lock, flags);
332
333		if (unlikely(!skb))
334			break;
335
336		if (unlikely(skb_shinfo(skb)->nr_frags >= MAX_SKB_FRAGS)) {
337			/* Frame count from host exceeds frags[] capacity */
338			dev_kfree_skb_any(skb);
339			if (fp->rx.skb == skb)
340				fp->rx.skb = NULL;
341			dev->stats.rx_length_errors++;
342			break;
343		}
344
345		if (skb->len == 0) { /* First fragment */
346			skb->protocol = htons(ETH_P_PHONET);
347			skb_reset_mac_header(skb);
348			/* Can't use pskb_pull() on page in IRQ */
349			skb_put_data(skb, page_address(page), 1);
350		}
351
352		skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page,
353				skb->len <= 1, req->actual, PAGE_SIZE);
354		page = NULL;
355
356		if (req->actual < req->length) { /* Last fragment */
357			skb->dev = dev;
358			dev->stats.rx_packets++;
359			dev->stats.rx_bytes += skb->len;
360
361			netif_rx(skb);
362		}
363		break;
364
365	/* Do not resubmit in these cases: */
366	case -ESHUTDOWN: /* disconnect */
367	case -ECONNABORTED: /* hw reset */
368	case -ECONNRESET: /* dequeued (unlink or netif down) */
369		req = NULL;
370		break;
371
372	/* Do resubmit in these cases: */
373	case -EOVERFLOW: /* request buffer overflow */
374		dev->stats.rx_over_errors++;
375		fallthrough;
376	default:
377		dev->stats.rx_errors++;
378		break;
379	}
380
381	if (page)
382		put_page(page);
383	if (req)
384		pn_rx_submit(fp, req, GFP_ATOMIC);
385}
386
387/*-------------------------------------------------------------------------*/
388
389static void __pn_reset(struct usb_function *f)
390{
391	struct f_phonet *fp = func_to_pn(f);
392	struct net_device *dev = fp->dev;
393	struct phonet_port *port = netdev_priv(dev);
394
395	netif_carrier_off(dev);
396	port->usb = NULL;
397
398	usb_ep_disable(fp->out_ep);
399	usb_ep_disable(fp->in_ep);
400	if (fp->rx.skb) {
401		dev_kfree_skb_irq(fp->rx.skb);
402		fp->rx.skb = NULL;
403	}
404}
405
406static int pn_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
407{
408	struct f_phonet *fp = func_to_pn(f);
409	struct usb_gadget *gadget = fp->function.config->cdev->gadget;
410
411	if (intf == pn_control_intf_desc.bInterfaceNumber)
412		/* control interface, no altsetting */
413		return (alt > 0) ? -EINVAL : 0;
414
415	if (intf == pn_data_intf_desc.bInterfaceNumber) {
416		struct net_device *dev = fp->dev;
417		struct phonet_port *port = netdev_priv(dev);
418
419		/* data intf (0: inactive, 1: active) */
420		if (alt > 1)
421			return -EINVAL;
422
423		spin_lock(&port->lock);
424
425		if (fp->in_ep->enabled)
426			__pn_reset(f);
427
428		if (alt == 1) {
429			int i;
430
431			if (config_ep_by_speed(gadget, f, fp->in_ep) ||
432			    config_ep_by_speed(gadget, f, fp->out_ep)) {
433				fp->in_ep->desc = NULL;
434				fp->out_ep->desc = NULL;
435				spin_unlock(&port->lock);
436				return -EINVAL;
437			}
438			usb_ep_enable(fp->out_ep);
439			usb_ep_enable(fp->in_ep);
440
441			port->usb = fp;
442			fp->out_ep->driver_data = fp;
443			fp->in_ep->driver_data = fp;
444
445			netif_carrier_on(dev);
446			for (i = 0; i < phonet_rxq_size; i++)
447				pn_rx_submit(fp, fp->out_reqv[i], GFP_ATOMIC);
448		}
449		spin_unlock(&port->lock);
450		return 0;
451	}
452
453	return -EINVAL;
454}
455
456static int pn_get_alt(struct usb_function *f, unsigned intf)
457{
458	struct f_phonet *fp = func_to_pn(f);
459
460	if (intf == pn_control_intf_desc.bInterfaceNumber)
461		return 0;
462
463	if (intf == pn_data_intf_desc.bInterfaceNumber) {
464		struct phonet_port *port = netdev_priv(fp->dev);
465		u8 alt;
466
467		spin_lock(&port->lock);
468		alt = port->usb != NULL;
469		spin_unlock(&port->lock);
470		return alt;
471	}
472
473	return -EINVAL;
474}
475
476static void pn_disconnect(struct usb_function *f)
477{
478	struct f_phonet *fp = func_to_pn(f);
479	struct phonet_port *port = netdev_priv(fp->dev);
480	unsigned long flags;
481
482	/* remain disabled until set_alt */
483	spin_lock_irqsave(&port->lock, flags);
484	__pn_reset(f);
485	spin_unlock_irqrestore(&port->lock, flags);
486}
487
488/*-------------------------------------------------------------------------*/
489
490static int pn_bind(struct usb_configuration *c, struct usb_function *f)
491{
492	struct usb_composite_dev *cdev = c->cdev;
493	struct usb_gadget *gadget = cdev->gadget;
494	struct f_phonet *fp = func_to_pn(f);
495	struct usb_ep *ep;
496	int status, i;
497
498	struct f_phonet_opts *phonet_opts;
499
500	phonet_opts = container_of(f->fi, struct f_phonet_opts, func_inst);
501
502	/*
503	 * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
504	 * configurations are bound in sequence with list_for_each_entry,
505	 * in each configuration its functions are bound in sequence
506	 * with list_for_each_entry, so we assume no race condition
507	 * with regard to phonet_opts->bound access
508	 */
509	if (!phonet_opts->bound) {
510		gphonet_set_gadget(phonet_opts->net, gadget);
511		status = gphonet_register_netdev(phonet_opts->net);
512		if (status)
513			return status;
514		phonet_opts->bound = true;
515	}
516
517	/* Reserve interface IDs */
518	status = usb_interface_id(c, f);
519	if (status < 0)
520		goto err;
521	pn_control_intf_desc.bInterfaceNumber = status;
522	pn_union_desc.bMasterInterface0 = status;
523
524	status = usb_interface_id(c, f);
525	if (status < 0)
526		goto err;
527	pn_data_nop_intf_desc.bInterfaceNumber = status;
528	pn_data_intf_desc.bInterfaceNumber = status;
529	pn_union_desc.bSlaveInterface0 = status;
530
531	/* Reserve endpoints */
532	status = -ENODEV;
533	ep = usb_ep_autoconfig(gadget, &pn_fs_sink_desc);
534	if (!ep)
535		goto err;
536	fp->out_ep = ep;
537
538	ep = usb_ep_autoconfig(gadget, &pn_fs_source_desc);
539	if (!ep)
540		goto err;
541	fp->in_ep = ep;
542
543	pn_hs_sink_desc.bEndpointAddress = pn_fs_sink_desc.bEndpointAddress;
544	pn_hs_source_desc.bEndpointAddress = pn_fs_source_desc.bEndpointAddress;
545
546	/* Do not try to bind Phonet twice... */
547	status = usb_assign_descriptors(f, fs_pn_function, hs_pn_function,
548			NULL, NULL);
549	if (status)
550		goto err;
551
552	/* Incoming USB requests */
553	status = -ENOMEM;
554	for (i = 0; i < phonet_rxq_size; i++) {
555		struct usb_request *req;
556
557		req = usb_ep_alloc_request(fp->out_ep, GFP_KERNEL);
558		if (!req)
559			goto err_req;
560
561		req->complete = pn_rx_complete;
562		fp->out_reqv[i] = req;
563	}
564
565	/* Outgoing USB requests */
566	fp->in_req = usb_ep_alloc_request(fp->in_ep, GFP_KERNEL);
567	if (!fp->in_req)
568		goto err_req;
569
570	INFO(cdev, "USB CDC Phonet function\n");
571	INFO(cdev, "using %s, OUT %s, IN %s\n", cdev->gadget->name,
572		fp->out_ep->name, fp->in_ep->name);
573	return 0;
574
575err_req:
576	for (i = 0; i < phonet_rxq_size && fp->out_reqv[i]; i++)
577		usb_ep_free_request(fp->out_ep, fp->out_reqv[i]);
578	usb_free_all_descriptors(f);
579err:
580	ERROR(cdev, "USB CDC Phonet: cannot autoconfigure\n");
581	return status;
582}
583
584static inline struct f_phonet_opts *to_f_phonet_opts(struct config_item *item)
585{
586	return container_of(to_config_group(item), struct f_phonet_opts,
587			func_inst.group);
588}
589
590static void phonet_attr_release(struct config_item *item)
591{
592	struct f_phonet_opts *opts = to_f_phonet_opts(item);
593
594	usb_put_function_instance(&opts->func_inst);
595}
596
597static struct configfs_item_operations phonet_item_ops = {
598	.release		= phonet_attr_release,
599};
600
601static ssize_t f_phonet_ifname_show(struct config_item *item, char *page)
602{
603	return gether_get_ifname(to_f_phonet_opts(item)->net, page, PAGE_SIZE);
604}
605
606CONFIGFS_ATTR_RO(f_phonet_, ifname);
607
608static struct configfs_attribute *phonet_attrs[] = {
609	&f_phonet_attr_ifname,
610	NULL,
611};
612
613static const struct config_item_type phonet_func_type = {
614	.ct_item_ops	= &phonet_item_ops,
615	.ct_attrs	= phonet_attrs,
616	.ct_owner	= THIS_MODULE,
617};
618
619static void phonet_free_inst(struct usb_function_instance *f)
620{
621	struct f_phonet_opts *opts;
622
623	opts = container_of(f, struct f_phonet_opts, func_inst);
624	if (opts->bound)
625		gphonet_cleanup(opts->net);
626	else
627		free_netdev(opts->net);
628	kfree(opts);
629}
630
631static struct usb_function_instance *phonet_alloc_inst(void)
632{
633	struct f_phonet_opts *opts;
634
635	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
636	if (!opts)
637		return ERR_PTR(-ENOMEM);
638
639	opts->func_inst.free_func_inst = phonet_free_inst;
640	opts->net = gphonet_setup_default();
641	if (IS_ERR(opts->net)) {
642		struct net_device *net = opts->net;
643		kfree(opts);
644		return ERR_CAST(net);
645	}
646
647	config_group_init_type_name(&opts->func_inst.group, "",
648			&phonet_func_type);
649
650	return &opts->func_inst;
651}
652
653static void phonet_free(struct usb_function *f)
654{
655	struct f_phonet *phonet;
656
657	phonet = func_to_pn(f);
658	kfree(phonet);
659}
660
661static void pn_unbind(struct usb_configuration *c, struct usb_function *f)
662{
663	struct f_phonet *fp = func_to_pn(f);
664	int i;
665
666	/* We are already disconnected */
667	if (fp->in_req)
668		usb_ep_free_request(fp->in_ep, fp->in_req);
669	for (i = 0; i < phonet_rxq_size; i++)
670		if (fp->out_reqv[i])
671			usb_ep_free_request(fp->out_ep, fp->out_reqv[i]);
672
673	usb_free_all_descriptors(f);
674}
675
676static struct usb_function *phonet_alloc(struct usb_function_instance *fi)
677{
678	struct f_phonet *fp;
679	struct f_phonet_opts *opts;
680
681	fp = kzalloc(struct_size(fp, out_reqv, phonet_rxq_size), GFP_KERNEL);
682	if (!fp)
683		return ERR_PTR(-ENOMEM);
684
685	opts = container_of(fi, struct f_phonet_opts, func_inst);
686
687	fp->dev = opts->net;
688	fp->function.name = "phonet";
689	fp->function.bind = pn_bind;
690	fp->function.unbind = pn_unbind;
691	fp->function.set_alt = pn_set_alt;
692	fp->function.get_alt = pn_get_alt;
693	fp->function.disable = pn_disconnect;
694	fp->function.free_func = phonet_free;
695	spin_lock_init(&fp->rx.lock);
696
697	return &fp->function;
698}
699
700struct net_device *gphonet_setup_default(void)
701{
702	struct net_device *dev;
703	struct phonet_port *port;
704
705	/* Create net device */
706	dev = alloc_netdev(sizeof(*port), "upnlink%d", NET_NAME_UNKNOWN,
707			   pn_net_setup);
708	if (!dev)
709		return ERR_PTR(-ENOMEM);
710
711	port = netdev_priv(dev);
712	spin_lock_init(&port->lock);
713	netif_carrier_off(dev);
714
715	return dev;
716}
717
718void gphonet_set_gadget(struct net_device *net, struct usb_gadget *g)
719{
720	SET_NETDEV_DEV(net, &g->dev);
721}
722
723int gphonet_register_netdev(struct net_device *net)
724{
725	int status;
726
727	status = register_netdev(net);
728	if (status)
729		free_netdev(net);
730
731	return status;
732}
733
734void gphonet_cleanup(struct net_device *dev)
735{
736	unregister_netdev(dev);
737}
738
739DECLARE_USB_FUNCTION_INIT(phonet, phonet_alloc_inst, phonet_alloc);
740MODULE_AUTHOR("Rémi Denis-Courmont");
741MODULE_DESCRIPTION("USB CDC Phonet function");
742MODULE_LICENSE("GPL");