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 
36 struct phonet_port {
37 	struct f_phonet			*usb;
38 	spinlock_t			lock;
39 };
40 
41 struct 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 
54 static int phonet_rxq_size = 17;
55 
56 static 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 
66 static struct usb_interface_descriptor
67 pn_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 
76 static const struct usb_cdc_header_desc
77 pn_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 
84 static const struct usb_cdc_header_desc
85 pn_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 
92 static struct usb_cdc_union_desc
93 pn_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 
102 static struct usb_interface_descriptor
103 pn_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 
113 static struct usb_interface_descriptor
114 pn_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 
124 static struct usb_endpoint_descriptor
125 pn_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 
133 static struct usb_endpoint_descriptor
134 pn_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 
143 static struct usb_endpoint_descriptor
144 pn_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 
152 static struct usb_endpoint_descriptor
153 pn_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 
162 static 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 
174 static 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 
188 static int pn_net_open(struct net_device *dev)
189 {
190 	netif_wake_queue(dev);
191 	return 0;
192 }
193 
194 static int pn_net_close(struct net_device *dev)
195 {
196 	netif_stop_queue(dev);
197 	return 0;
198 }
199 
200 static 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 		/* fall through */
216 	default:
217 		dev->stats.tx_errors++;
218 	}
219 
220 	dev_kfree_skb_any(skb);
221 	netif_wake_queue(dev);
222 }
223 
224 static 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 
252 out_unlock:
253 	spin_unlock_irqrestore(&port->lock, flags);
254 out:
255 	if (unlikely(skb)) {
256 		dev_kfree_skb(skb);
257 		dev->stats.tx_dropped++;
258 	}
259 	return NETDEV_TX_OK;
260 }
261 
262 static 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 
268 static void pn_net_setup(struct net_device *dev)
269 {
270 	dev->features		= 0;
271 	dev->type		= ARPHRD_PHONET;
272 	dev->flags		= IFF_POINTOPOINT | IFF_NOARP;
273 	dev->mtu		= PHONET_DEV_MTU;
274 	dev->min_mtu		= PHONET_MIN_MTU;
275 	dev->max_mtu		= PHONET_MAX_MTU;
276 	dev->hard_header_len	= 1;
277 	dev->dev_addr[0]	= PN_MEDIA_USB;
278 	dev->addr_len		= 1;
279 	dev->tx_queue_len	= 1;
280 
281 	dev->netdev_ops		= &pn_netdev_ops;
282 	dev->needs_free_netdev	= true;
283 	dev->header_ops		= &phonet_header_ops;
284 }
285 
286 /*-------------------------------------------------------------------------*/
287 
288 /*
289  * Queue buffer for data from the host
290  */
291 static int
292 pn_rx_submit(struct f_phonet *fp, struct usb_request *req, gfp_t gfp_flags)
293 {
294 	struct page *page;
295 	int err;
296 
297 	page = __dev_alloc_page(gfp_flags | __GFP_NOMEMALLOC);
298 	if (!page)
299 		return -ENOMEM;
300 
301 	req->buf = page_address(page);
302 	req->length = PAGE_SIZE;
303 	req->context = page;
304 
305 	err = usb_ep_queue(fp->out_ep, req, gfp_flags);
306 	if (unlikely(err))
307 		put_page(page);
308 	return err;
309 }
310 
311 static void pn_rx_complete(struct usb_ep *ep, struct usb_request *req)
312 {
313 	struct f_phonet *fp = ep->driver_data;
314 	struct net_device *dev = fp->dev;
315 	struct page *page = req->context;
316 	struct sk_buff *skb;
317 	unsigned long flags;
318 	int status = req->status;
319 
320 	switch (status) {
321 	case 0:
322 		spin_lock_irqsave(&fp->rx.lock, flags);
323 		skb = fp->rx.skb;
324 		if (!skb)
325 			skb = fp->rx.skb = netdev_alloc_skb(dev, 12);
326 		if (req->actual < req->length) /* Last fragment */
327 			fp->rx.skb = NULL;
328 		spin_unlock_irqrestore(&fp->rx.lock, flags);
329 
330 		if (unlikely(!skb))
331 			break;
332 
333 		if (skb->len == 0) { /* First fragment */
334 			skb->protocol = htons(ETH_P_PHONET);
335 			skb_reset_mac_header(skb);
336 			/* Can't use pskb_pull() on page in IRQ */
337 			skb_put_data(skb, page_address(page), 1);
338 		}
339 
340 		skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page,
341 				skb->len <= 1, req->actual, PAGE_SIZE);
342 		page = NULL;
343 
344 		if (req->actual < req->length) { /* Last fragment */
345 			skb->dev = dev;
346 			dev->stats.rx_packets++;
347 			dev->stats.rx_bytes += skb->len;
348 
349 			netif_rx(skb);
350 		}
351 		break;
352 
353 	/* Do not resubmit in these cases: */
354 	case -ESHUTDOWN: /* disconnect */
355 	case -ECONNABORTED: /* hw reset */
356 	case -ECONNRESET: /* dequeued (unlink or netif down) */
357 		req = NULL;
358 		break;
359 
360 	/* Do resubmit in these cases: */
361 	case -EOVERFLOW: /* request buffer overflow */
362 		dev->stats.rx_over_errors++;
363 		/* fall through */
364 	default:
365 		dev->stats.rx_errors++;
366 		break;
367 	}
368 
369 	if (page)
370 		put_page(page);
371 	if (req)
372 		pn_rx_submit(fp, req, GFP_ATOMIC);
373 }
374 
375 /*-------------------------------------------------------------------------*/
376 
377 static void __pn_reset(struct usb_function *f)
378 {
379 	struct f_phonet *fp = func_to_pn(f);
380 	struct net_device *dev = fp->dev;
381 	struct phonet_port *port = netdev_priv(dev);
382 
383 	netif_carrier_off(dev);
384 	port->usb = NULL;
385 
386 	usb_ep_disable(fp->out_ep);
387 	usb_ep_disable(fp->in_ep);
388 	if (fp->rx.skb) {
389 		dev_kfree_skb_irq(fp->rx.skb);
390 		fp->rx.skb = NULL;
391 	}
392 }
393 
394 static int pn_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
395 {
396 	struct f_phonet *fp = func_to_pn(f);
397 	struct usb_gadget *gadget = fp->function.config->cdev->gadget;
398 
399 	if (intf == pn_control_intf_desc.bInterfaceNumber)
400 		/* control interface, no altsetting */
401 		return (alt > 0) ? -EINVAL : 0;
402 
403 	if (intf == pn_data_intf_desc.bInterfaceNumber) {
404 		struct net_device *dev = fp->dev;
405 		struct phonet_port *port = netdev_priv(dev);
406 
407 		/* data intf (0: inactive, 1: active) */
408 		if (alt > 1)
409 			return -EINVAL;
410 
411 		spin_lock(&port->lock);
412 
413 		if (fp->in_ep->enabled)
414 			__pn_reset(f);
415 
416 		if (alt == 1) {
417 			int i;
418 
419 			if (config_ep_by_speed(gadget, f, fp->in_ep) ||
420 			    config_ep_by_speed(gadget, f, fp->out_ep)) {
421 				fp->in_ep->desc = NULL;
422 				fp->out_ep->desc = NULL;
423 				spin_unlock(&port->lock);
424 				return -EINVAL;
425 			}
426 			usb_ep_enable(fp->out_ep);
427 			usb_ep_enable(fp->in_ep);
428 
429 			port->usb = fp;
430 			fp->out_ep->driver_data = fp;
431 			fp->in_ep->driver_data = fp;
432 
433 			netif_carrier_on(dev);
434 			for (i = 0; i < phonet_rxq_size; i++)
435 				pn_rx_submit(fp, fp->out_reqv[i], GFP_ATOMIC);
436 		}
437 		spin_unlock(&port->lock);
438 		return 0;
439 	}
440 
441 	return -EINVAL;
442 }
443 
444 static int pn_get_alt(struct usb_function *f, unsigned intf)
445 {
446 	struct f_phonet *fp = func_to_pn(f);
447 
448 	if (intf == pn_control_intf_desc.bInterfaceNumber)
449 		return 0;
450 
451 	if (intf == pn_data_intf_desc.bInterfaceNumber) {
452 		struct phonet_port *port = netdev_priv(fp->dev);
453 		u8 alt;
454 
455 		spin_lock(&port->lock);
456 		alt = port->usb != NULL;
457 		spin_unlock(&port->lock);
458 		return alt;
459 	}
460 
461 	return -EINVAL;
462 }
463 
464 static void pn_disconnect(struct usb_function *f)
465 {
466 	struct f_phonet *fp = func_to_pn(f);
467 	struct phonet_port *port = netdev_priv(fp->dev);
468 	unsigned long flags;
469 
470 	/* remain disabled until set_alt */
471 	spin_lock_irqsave(&port->lock, flags);
472 	__pn_reset(f);
473 	spin_unlock_irqrestore(&port->lock, flags);
474 }
475 
476 /*-------------------------------------------------------------------------*/
477 
478 static int pn_bind(struct usb_configuration *c, struct usb_function *f)
479 {
480 	struct usb_composite_dev *cdev = c->cdev;
481 	struct usb_gadget *gadget = cdev->gadget;
482 	struct f_phonet *fp = func_to_pn(f);
483 	struct usb_ep *ep;
484 	int status, i;
485 
486 	struct f_phonet_opts *phonet_opts;
487 
488 	phonet_opts = container_of(f->fi, struct f_phonet_opts, func_inst);
489 
490 	/*
491 	 * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
492 	 * configurations are bound in sequence with list_for_each_entry,
493 	 * in each configuration its functions are bound in sequence
494 	 * with list_for_each_entry, so we assume no race condition
495 	 * with regard to phonet_opts->bound access
496 	 */
497 	if (!phonet_opts->bound) {
498 		gphonet_set_gadget(phonet_opts->net, gadget);
499 		status = gphonet_register_netdev(phonet_opts->net);
500 		if (status)
501 			return status;
502 		phonet_opts->bound = true;
503 	}
504 
505 	/* Reserve interface IDs */
506 	status = usb_interface_id(c, f);
507 	if (status < 0)
508 		goto err;
509 	pn_control_intf_desc.bInterfaceNumber = status;
510 	pn_union_desc.bMasterInterface0 = status;
511 
512 	status = usb_interface_id(c, f);
513 	if (status < 0)
514 		goto err;
515 	pn_data_nop_intf_desc.bInterfaceNumber = status;
516 	pn_data_intf_desc.bInterfaceNumber = status;
517 	pn_union_desc.bSlaveInterface0 = status;
518 
519 	/* Reserve endpoints */
520 	status = -ENODEV;
521 	ep = usb_ep_autoconfig(gadget, &pn_fs_sink_desc);
522 	if (!ep)
523 		goto err;
524 	fp->out_ep = ep;
525 
526 	ep = usb_ep_autoconfig(gadget, &pn_fs_source_desc);
527 	if (!ep)
528 		goto err;
529 	fp->in_ep = ep;
530 
531 	pn_hs_sink_desc.bEndpointAddress = pn_fs_sink_desc.bEndpointAddress;
532 	pn_hs_source_desc.bEndpointAddress = pn_fs_source_desc.bEndpointAddress;
533 
534 	/* Do not try to bind Phonet twice... */
535 	status = usb_assign_descriptors(f, fs_pn_function, hs_pn_function,
536 			NULL, NULL);
537 	if (status)
538 		goto err;
539 
540 	/* Incoming USB requests */
541 	status = -ENOMEM;
542 	for (i = 0; i < phonet_rxq_size; i++) {
543 		struct usb_request *req;
544 
545 		req = usb_ep_alloc_request(fp->out_ep, GFP_KERNEL);
546 		if (!req)
547 			goto err_req;
548 
549 		req->complete = pn_rx_complete;
550 		fp->out_reqv[i] = req;
551 	}
552 
553 	/* Outgoing USB requests */
554 	fp->in_req = usb_ep_alloc_request(fp->in_ep, GFP_KERNEL);
555 	if (!fp->in_req)
556 		goto err_req;
557 
558 	INFO(cdev, "USB CDC Phonet function\n");
559 	INFO(cdev, "using %s, OUT %s, IN %s\n", cdev->gadget->name,
560 		fp->out_ep->name, fp->in_ep->name);
561 	return 0;
562 
563 err_req:
564 	for (i = 0; i < phonet_rxq_size && fp->out_reqv[i]; i++)
565 		usb_ep_free_request(fp->out_ep, fp->out_reqv[i]);
566 	usb_free_all_descriptors(f);
567 err:
568 	ERROR(cdev, "USB CDC Phonet: cannot autoconfigure\n");
569 	return status;
570 }
571 
572 static inline struct f_phonet_opts *to_f_phonet_opts(struct config_item *item)
573 {
574 	return container_of(to_config_group(item), struct f_phonet_opts,
575 			func_inst.group);
576 }
577 
578 static void phonet_attr_release(struct config_item *item)
579 {
580 	struct f_phonet_opts *opts = to_f_phonet_opts(item);
581 
582 	usb_put_function_instance(&opts->func_inst);
583 }
584 
585 static struct configfs_item_operations phonet_item_ops = {
586 	.release		= phonet_attr_release,
587 };
588 
589 static ssize_t f_phonet_ifname_show(struct config_item *item, char *page)
590 {
591 	return gether_get_ifname(to_f_phonet_opts(item)->net, page, PAGE_SIZE);
592 }
593 
594 CONFIGFS_ATTR_RO(f_phonet_, ifname);
595 
596 static struct configfs_attribute *phonet_attrs[] = {
597 	&f_phonet_attr_ifname,
598 	NULL,
599 };
600 
601 static const struct config_item_type phonet_func_type = {
602 	.ct_item_ops	= &phonet_item_ops,
603 	.ct_attrs	= phonet_attrs,
604 	.ct_owner	= THIS_MODULE,
605 };
606 
607 static void phonet_free_inst(struct usb_function_instance *f)
608 {
609 	struct f_phonet_opts *opts;
610 
611 	opts = container_of(f, struct f_phonet_opts, func_inst);
612 	if (opts->bound)
613 		gphonet_cleanup(opts->net);
614 	else
615 		free_netdev(opts->net);
616 	kfree(opts);
617 }
618 
619 static struct usb_function_instance *phonet_alloc_inst(void)
620 {
621 	struct f_phonet_opts *opts;
622 
623 	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
624 	if (!opts)
625 		return ERR_PTR(-ENOMEM);
626 
627 	opts->func_inst.free_func_inst = phonet_free_inst;
628 	opts->net = gphonet_setup_default();
629 	if (IS_ERR(opts->net)) {
630 		struct net_device *net = opts->net;
631 		kfree(opts);
632 		return ERR_CAST(net);
633 	}
634 
635 	config_group_init_type_name(&opts->func_inst.group, "",
636 			&phonet_func_type);
637 
638 	return &opts->func_inst;
639 }
640 
641 static void phonet_free(struct usb_function *f)
642 {
643 	struct f_phonet *phonet;
644 
645 	phonet = func_to_pn(f);
646 	kfree(phonet);
647 }
648 
649 static void pn_unbind(struct usb_configuration *c, struct usb_function *f)
650 {
651 	struct f_phonet *fp = func_to_pn(f);
652 	int i;
653 
654 	/* We are already disconnected */
655 	if (fp->in_req)
656 		usb_ep_free_request(fp->in_ep, fp->in_req);
657 	for (i = 0; i < phonet_rxq_size; i++)
658 		if (fp->out_reqv[i])
659 			usb_ep_free_request(fp->out_ep, fp->out_reqv[i]);
660 
661 	usb_free_all_descriptors(f);
662 }
663 
664 static struct usb_function *phonet_alloc(struct usb_function_instance *fi)
665 {
666 	struct f_phonet *fp;
667 	struct f_phonet_opts *opts;
668 	int size;
669 
670 	size = sizeof(*fp) + (phonet_rxq_size * sizeof(struct usb_request *));
671 	fp = kzalloc(size, GFP_KERNEL);
672 	if (!fp)
673 		return ERR_PTR(-ENOMEM);
674 
675 	opts = container_of(fi, struct f_phonet_opts, func_inst);
676 
677 	fp->dev = opts->net;
678 	fp->function.name = "phonet";
679 	fp->function.bind = pn_bind;
680 	fp->function.unbind = pn_unbind;
681 	fp->function.set_alt = pn_set_alt;
682 	fp->function.get_alt = pn_get_alt;
683 	fp->function.disable = pn_disconnect;
684 	fp->function.free_func = phonet_free;
685 	spin_lock_init(&fp->rx.lock);
686 
687 	return &fp->function;
688 }
689 
690 struct net_device *gphonet_setup_default(void)
691 {
692 	struct net_device *dev;
693 	struct phonet_port *port;
694 
695 	/* Create net device */
696 	dev = alloc_netdev(sizeof(*port), "upnlink%d", NET_NAME_UNKNOWN,
697 			   pn_net_setup);
698 	if (!dev)
699 		return ERR_PTR(-ENOMEM);
700 
701 	port = netdev_priv(dev);
702 	spin_lock_init(&port->lock);
703 	netif_carrier_off(dev);
704 
705 	return dev;
706 }
707 
708 void gphonet_set_gadget(struct net_device *net, struct usb_gadget *g)
709 {
710 	SET_NETDEV_DEV(net, &g->dev);
711 }
712 
713 int gphonet_register_netdev(struct net_device *net)
714 {
715 	int status;
716 
717 	status = register_netdev(net);
718 	if (status)
719 		free_netdev(net);
720 
721 	return status;
722 }
723 
724 void gphonet_cleanup(struct net_device *dev)
725 {
726 	unregister_netdev(dev);
727 }
728 
729 DECLARE_USB_FUNCTION_INIT(phonet, phonet_alloc_inst, phonet_alloc);
730 MODULE_AUTHOR("Rémi Denis-Courmont");
731 MODULE_LICENSE("GPL");
732