summaryrefslogtreecommitdiff
path: root/drivers/net/usb/cdc-phonet.c
blob: 3886b30ed37355394e6155f60bb7e559e598391e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
/*
 * phonet.c -- USB CDC Phonet host driver
 *
 * Copyright (C) 2008-2009 Nokia Corporation. All rights reserved.
 *
 * Author: Rémi Denis-Courmont
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 */

#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/gfp.h>
#include <linux/usb.h>
#include <linux/usb/cdc.h>
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/if_phonet.h>
#include <linux/phonet.h>

#define PN_MEDIA_USB	0x1B

static const unsigned rxq_size = 17;

struct usbpn_dev {
	struct net_device	*dev;

	struct usb_interface	*intf, *data_intf;
	struct usb_device	*usb;
	unsigned int		tx_pipe, rx_pipe;
	u8 active_setting;
	u8 disconnected;

	unsigned		tx_queue;
	spinlock_t		tx_lock;

	spinlock_t		rx_lock;
	struct sk_buff		*rx_skb;
	struct urb		*urbs[0];
};

static void tx_complete(struct urb *req);
static void rx_complete(struct urb *req);

/*
 * Network device callbacks
 */
static netdev_tx_t usbpn_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct usbpn_dev *pnd = netdev_priv(dev);
	struct urb *req = NULL;
	unsigned long flags;
	int err;

	if (skb->protocol != htons(ETH_P_PHONET))
		goto drop;

	req = usb_alloc_urb(0, GFP_ATOMIC);
	if (!req)
		goto drop;
	usb_fill_bulk_urb(req, pnd->usb, pnd->tx_pipe, skb->data, skb->len,
				tx_complete, skb);
	req->transfer_flags = URB_ZERO_PACKET;
	err = usb_submit_urb(req, GFP_ATOMIC);
	if (err) {
		usb_free_urb(req);
		goto drop;
	}

	spin_lock_irqsave(&pnd->tx_lock, flags);
	pnd->tx_queue++;
	if (pnd->tx_queue >= dev->tx_queue_len)
		netif_stop_queue(dev);
	spin_unlock_irqrestore(&pnd->tx_lock, flags);
	return NETDEV_TX_OK;

drop:
	dev_kfree_skb(skb);
	dev->stats.tx_dropped++;
	return NETDEV_TX_OK;
}

static void tx_complete(struct urb *req)
{
	struct sk_buff *skb = req->context;
	struct net_device *dev = skb->dev;
	struct usbpn_dev *pnd = netdev_priv(dev);
	int status = req->status;

	switch (status) {
	case 0:
		dev->stats.tx_bytes += skb->len;
		break;

	case -ENOENT:
	case -ECONNRESET:
	case -ESHUTDOWN:
		dev->stats.tx_aborted_errors++;
	default:
		dev->stats.tx_errors++;
		dev_dbg(&dev->dev, "TX error (%d)\n", status);
	}
	dev->stats.tx_packets++;

	spin_lock(&pnd->tx_lock);
	pnd->tx_queue--;
	netif_wake_queue(dev);
	spin_unlock(&pnd->tx_lock);

	dev_kfree_skb_any(skb);
	usb_free_urb(req);
}

static int rx_submit(struct usbpn_dev *pnd, struct urb *req, gfp_t gfp_flags)
{
	struct net_device *dev = pnd->dev;
	struct page *page;
	int err;

	page = alloc_page(gfp_flags);
	if (!page)
		return -ENOMEM;

	usb_fill_bulk_urb(req, pnd->usb, pnd->rx_pipe, page_address(page),
				PAGE_SIZE, rx_complete, dev);
	req->transfer_flags = 0;
	err = usb_submit_urb(req, gfp_flags);
	if (unlikely(err)) {
		dev_dbg(&dev->dev, "RX submit error (%d)\n", err);
		put_page(page);
	}
	return err;
}

static void rx_complete(struct urb *req)
{
	struct net_device *dev = req->context;
	struct usbpn_dev *pnd = netdev_priv(dev);
	struct page *page = virt_to_page(req->transfer_buffer);
	struct sk_buff *skb;
	unsigned long flags;
	int status = req->status;

	switch (status) {
	case 0:
		spin_lock_irqsave(&pnd->rx_lock, flags);
		skb = pnd->rx_skb;
		if (!skb) {
			skb = pnd->rx_skb = netdev_alloc_skb(dev, 12);
			if (likely(skb)) {
				/* Can't use pskb_pull() on page in IRQ */
				memcpy(skb_put(skb, 1), page_address(page), 1);
				skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
						page, 1, req->actual_length,
						req->actual_length);
				page = NULL;
			}
		} else {
			skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
					page, 0, req->actual_length,
					req->actual_length);
			page = NULL;
		}
		if (req->actual_length < PAGE_SIZE)
			pnd->rx_skb = NULL; /* Last fragment */
		else
			skb = NULL;
		spin_unlock_irqrestore(&pnd->rx_lock, flags);
		if (skb) {
			skb->protocol = htons(ETH_P_PHONET);
			skb_reset_mac_header(skb);
			__skb_pull(skb, 1);
			skb->dev = dev;
			dev->stats.rx_packets++;
			dev->stats.rx_bytes += skb->len;

			netif_rx(skb);
		}
		goto resubmit;

	case -ENOENT:
	case -ECONNRESET:
	case -ESHUTDOWN:
		req = NULL;
		break;

	case -EOVERFLOW:
		dev->stats.rx_over_errors++;
		dev_dbg(&dev->dev, "RX overflow\n");
		break;

	case -EILSEQ:
		dev->stats.rx_crc_errors++;
		break;
	}

	dev->stats.rx_errors++;
resubmit:
	if (page)
		put_page(page);
	if (req)
		rx_submit(pnd, req, GFP_ATOMIC | __GFP_COLD);
}

static int usbpn_close(struct net_device *dev);

static int usbpn_open(struct net_device *dev)
{
	struct usbpn_dev *pnd = netdev_priv(dev);
	int err;
	unsigned i;
	unsigned num = pnd->data_intf->cur_altsetting->desc.bInterfaceNumber;

	err = usb_set_interface(pnd->usb, num, pnd->active_setting);
	if (err)
		return err;

	for (i = 0; i < rxq_size; i++) {
		struct urb *req = usb_alloc_urb(0, GFP_KERNEL);

		if (!req || rx_submit(pnd, req, GFP_KERNEL | __GFP_COLD)) {
			usbpn_close(dev);
			return -ENOMEM;
		}
		pnd->urbs[i] = req;
	}

	netif_wake_queue(dev);
	return 0;
}

static int usbpn_close(struct net_device *dev)
{
	struct usbpn_dev *pnd = netdev_priv(dev);
	unsigned i;
	unsigned num = pnd->data_intf->cur_altsetting->desc.bInterfaceNumber;

	netif_stop_queue(dev);

	for (i = 0; i < rxq_size; i++) {
		struct urb *req = pnd->urbs[i];

		if (!req)
			continue;
		usb_kill_urb(req);
		usb_free_urb(req);
		pnd->urbs[i] = NULL;
	}

	return usb_set_interface(pnd->usb, num, !pnd->active_setting);
}

static int usbpn_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
	struct if_phonet_req *req = (struct if_phonet_req *)ifr;

	switch (cmd) {
	case SIOCPNGAUTOCONF:
		req->ifr_phonet_autoconf.device = PN_DEV_PC;
		return 0;
	}
	return -ENOIOCTLCMD;
}

static int usbpn_set_mtu(struct net_device *dev, int new_mtu)
{
	if ((new_mtu < PHONET_MIN_MTU) || (new_mtu > PHONET_MAX_MTU))
		return -EINVAL;

	dev->mtu = new_mtu;
	return 0;
}

static const struct net_device_ops usbpn_ops = {
	.ndo_open	= usbpn_open,
	.ndo_stop	= usbpn_close,
	.ndo_start_xmit = usbpn_xmit,
	.ndo_do_ioctl	= usbpn_ioctl,
	.ndo_change_mtu = usbpn_set_mtu,
};

static void usbpn_setup(struct net_device *dev)
{
	dev->features		= 0;
	dev->netdev_ops		= &usbpn_ops,
	dev->header_ops		= &phonet_header_ops;
	dev->type		= ARPHRD_PHONET;
	dev->flags		= IFF_POINTOPOINT | IFF_NOARP;
	dev->mtu		= PHONET_MAX_MTU;
	dev->hard_header_len	= 1;
	dev->dev_addr[0]	= PN_MEDIA_USB;
	dev->addr_len		= 1;
	dev->tx_queue_len	= 3;

	dev->destructor		= free_netdev;
}

/*
 * USB driver callbacks
 */
static struct usb_device_id usbpn_ids[] = {
	{
		.match_flags = USB_DEVICE_ID_MATCH_VENDOR
			| USB_DEVICE_ID_MATCH_INT_CLASS
			| USB_DEVICE_ID_MATCH_INT_SUBCLASS,
		.idVendor = 0x0421, /* Nokia */
		.bInterfaceClass = USB_CLASS_COMM,
		.bInterfaceSubClass = 0xFE,
	},
	{ },
};

MODULE_DEVICE_TABLE(usb, usbpn_ids);

static struct usb_driver usbpn_driver;

int usbpn_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
	static const char ifname[] = "usbpn%d";
	const struct usb_cdc_union_desc *union_header = NULL;
	const struct usb_host_interface *data_desc;
	struct usb_interface *data_intf;
	struct usb_device *usbdev = interface_to_usbdev(intf);
	struct net_device *dev;
	struct usbpn_dev *pnd;
	u8 *data;
	int phonet = 0;
	int len, err;

	data = intf->altsetting->extra;
	len = intf->altsetting->extralen;
	while (len >= 3) {
		u8 dlen = data[0];
		if (dlen < 3)
			return -EINVAL;

		/* bDescriptorType */
		if (data[1] == USB_DT_CS_INTERFACE) {
			/* bDescriptorSubType */
			switch (data[2]) {
			case USB_CDC_UNION_TYPE:
				if (union_header || dlen < 5)
					break;
				union_header =
					(struct usb_cdc_union_desc *)data;
				break;
			case 0xAB:
				phonet = 1;
				break;
			}
		}
		data += dlen;
		len -= dlen;
	}

	if (!union_header || !phonet)
		return -EINVAL;

	data_intf = usb_ifnum_to_if(usbdev, union_header->bSlaveInterface0);
	if (data_intf == NULL)
		return -ENODEV;
	/* Data interface has one inactive and one active setting */
	if (data_intf->num_altsetting != 2)
		return -EINVAL;
	if (data_intf->altsetting[0].desc.bNumEndpoints == 0 &&
	    data_intf->altsetting[1].desc.bNumEndpoints == 2)
		data_desc = data_intf->altsetting + 1;
	else
	if (data_intf->altsetting[0].desc.bNumEndpoints == 2 &&
	    data_intf->altsetting[1].desc.bNumEndpoints == 0)
		data_desc = data_intf->altsetting;
	else
		return -EINVAL;

	dev = alloc_netdev(sizeof(*pnd) + sizeof(pnd->urbs[0]) * rxq_size,
				ifname, usbpn_setup);
	if (!dev)
		return -ENOMEM;

	pnd = netdev_priv(dev);
	SET_NETDEV_DEV(dev, &intf->dev);

	pnd->dev = dev;
	pnd->usb = usb_get_dev(usbdev);
	pnd->intf = intf;
	pnd->data_intf = data_intf;
	spin_lock_init(&pnd->tx_lock);
	spin_lock_init(&pnd->rx_lock);
	/* Endpoints */
	if (usb_pipein(data_desc->endpoint[0].desc.bEndpointAddress)) {
		pnd->rx_pipe = usb_rcvbulkpipe(usbdev,
			data_desc->endpoint[0].desc.bEndpointAddress);
		pnd->tx_pipe = usb_sndbulkpipe(usbdev,
			data_desc->endpoint[1].desc.bEndpointAddress);
	} else {
		pnd->rx_pipe = usb_rcvbulkpipe(usbdev,
			data_desc->endpoint[1].desc.bEndpointAddress);
		pnd->tx_pipe = usb_sndbulkpipe(usbdev,
			data_desc->endpoint[0].desc.bEndpointAddress);
	}
	pnd->active_setting = data_desc - data_intf->altsetting;

	err = usb_driver_claim_interface(&usbpn_driver, data_intf, pnd);
	if (err)
		goto out;

	/* Force inactive mode until the network device is brought UP */
	usb_set_interface(usbdev, union_header->bSlaveInterface0,
				!pnd->active_setting);
	usb_set_intfdata(intf, pnd);

	err = register_netdev(dev);
	if (err) {
		usb_driver_release_interface(&usbpn_driver, data_intf);
		goto out;
	}

	dev_dbg(&dev->dev, "USB CDC Phonet device found\n");
	return 0;

out:
	usb_set_intfdata(intf, NULL);
	free_netdev(dev);
	return err;
}

static void usbpn_disconnect(struct usb_interface *intf)
{
	struct usbpn_dev *pnd = usb_get_intfdata(intf);
	struct usb_device *usb = pnd->usb;

	if (pnd->disconnected)
		return;

	pnd->disconnected = 1;
	usb_driver_release_interface(&usbpn_driver,
			(pnd->intf == intf) ? pnd->data_intf : pnd->intf);
	unregister_netdev(pnd->dev);
	usb_put_dev(usb);
}

static struct usb_driver usbpn_driver = {
	.name =		"cdc_phonet",
	.probe =	usbpn_probe,
	.disconnect =	usbpn_disconnect,
	.id_table =	usbpn_ids,
};

module_usb_driver(usbpn_driver);

MODULE_AUTHOR("Remi Denis-Courmont");
MODULE_DESCRIPTION("USB CDC Phonet host interface");
MODULE_LICENSE("GPL");