1 /*
2 * phonet.c -- USB CDC Phonet host driver
3 *
4 * Copyright (C) 2008-2009 Nokia Corporation. All rights reserved.
5 *
6 * Author: Rémi Denis-Courmont
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * version 2 as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20 * 02110-1301 USA
21 */
22
23 #include <linux/kernel.h>
24 #include <linux/mm.h>
25 #include <linux/module.h>
26 #include <linux/gfp.h>
27 #include <linux/usb.h>
28 #include <linux/usb/cdc.h>
29 #include <linux/netdevice.h>
30 #include <linux/if_arp.h>
31 #include <linux/if_phonet.h>
32 #include <linux/phonet.h>
33
34 #define PN_MEDIA_USB 0x1B
35
36 static const unsigned rxq_size = 17;
37
38 struct usbpn_dev {
39 struct net_device *dev;
40
41 struct usb_interface *intf, *data_intf;
42 struct usb_device *usb;
43 unsigned int tx_pipe, rx_pipe;
44 u8 active_setting;
45 u8 disconnected;
46
47 unsigned tx_queue;
48 spinlock_t tx_lock;
49
50 spinlock_t rx_lock;
51 struct sk_buff *rx_skb;
52 struct urb *urbs[0];
53 };
54
55 static void tx_complete(struct urb *req);
56 static void rx_complete(struct urb *req);
57
58 /*
59 * Network device callbacks
60 */
usbpn_xmit(struct sk_buff * skb,struct net_device * dev)61 static netdev_tx_t usbpn_xmit(struct sk_buff *skb, struct net_device *dev)
62 {
63 struct usbpn_dev *pnd = netdev_priv(dev);
64 struct urb *req = NULL;
65 unsigned long flags;
66 int err;
67
68 if (skb->protocol != htons(ETH_P_PHONET))
69 goto drop;
70
71 req = usb_alloc_urb(0, GFP_ATOMIC);
72 if (!req)
73 goto drop;
74 usb_fill_bulk_urb(req, pnd->usb, pnd->tx_pipe, skb->data, skb->len,
75 tx_complete, skb);
76 req->transfer_flags = URB_ZERO_PACKET;
77 err = usb_submit_urb(req, GFP_ATOMIC);
78 if (err) {
79 usb_free_urb(req);
80 goto drop;
81 }
82
83 spin_lock_irqsave(&pnd->tx_lock, flags);
84 pnd->tx_queue++;
85 if (pnd->tx_queue >= dev->tx_queue_len)
86 netif_stop_queue(dev);
87 spin_unlock_irqrestore(&pnd->tx_lock, flags);
88 return NETDEV_TX_OK;
89
90 drop:
91 dev_kfree_skb(skb);
92 dev->stats.tx_dropped++;
93 return NETDEV_TX_OK;
94 }
95
tx_complete(struct urb * req)96 static void tx_complete(struct urb *req)
97 {
98 struct sk_buff *skb = req->context;
99 struct net_device *dev = skb->dev;
100 struct usbpn_dev *pnd = netdev_priv(dev);
101 int status = req->status;
102 unsigned long flags;
103
104 switch (status) {
105 case 0:
106 dev->stats.tx_bytes += skb->len;
107 break;
108
109 case -ENOENT:
110 case -ECONNRESET:
111 case -ESHUTDOWN:
112 dev->stats.tx_aborted_errors++;
113 /* fall through */
114 default:
115 dev->stats.tx_errors++;
116 dev_dbg(&dev->dev, "TX error (%d)\n", status);
117 }
118 dev->stats.tx_packets++;
119
120 spin_lock_irqsave(&pnd->tx_lock, flags);
121 pnd->tx_queue--;
122 netif_wake_queue(dev);
123 spin_unlock_irqrestore(&pnd->tx_lock, flags);
124
125 dev_kfree_skb_any(skb);
126 usb_free_urb(req);
127 }
128
rx_submit(struct usbpn_dev * pnd,struct urb * req,gfp_t gfp_flags)129 static int rx_submit(struct usbpn_dev *pnd, struct urb *req, gfp_t gfp_flags)
130 {
131 struct net_device *dev = pnd->dev;
132 struct page *page;
133 int err;
134
135 page = __dev_alloc_page(gfp_flags | __GFP_NOMEMALLOC);
136 if (!page)
137 return -ENOMEM;
138
139 usb_fill_bulk_urb(req, pnd->usb, pnd->rx_pipe, page_address(page),
140 PAGE_SIZE, rx_complete, dev);
141 req->transfer_flags = 0;
142 err = usb_submit_urb(req, gfp_flags);
143 if (unlikely(err)) {
144 dev_dbg(&dev->dev, "RX submit error (%d)\n", err);
145 put_page(page);
146 }
147 return err;
148 }
149
rx_complete(struct urb * req)150 static void rx_complete(struct urb *req)
151 {
152 struct net_device *dev = req->context;
153 struct usbpn_dev *pnd = netdev_priv(dev);
154 struct page *page = virt_to_page(req->transfer_buffer);
155 struct sk_buff *skb;
156 unsigned long flags;
157 int status = req->status;
158
159 switch (status) {
160 case 0:
161 spin_lock_irqsave(&pnd->rx_lock, flags);
162 skb = pnd->rx_skb;
163 if (!skb) {
164 skb = pnd->rx_skb = netdev_alloc_skb(dev, 12);
165 if (likely(skb)) {
166 /* Can't use pskb_pull() on page in IRQ */
167 skb_put_data(skb, page_address(page), 1);
168 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
169 page, 1, req->actual_length,
170 PAGE_SIZE);
171 page = NULL;
172 }
173 } else {
174 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
175 page, 0, req->actual_length,
176 PAGE_SIZE);
177 page = NULL;
178 }
179 if (req->actual_length < PAGE_SIZE)
180 pnd->rx_skb = NULL; /* Last fragment */
181 else
182 skb = NULL;
183 spin_unlock_irqrestore(&pnd->rx_lock, flags);
184 if (skb) {
185 skb->protocol = htons(ETH_P_PHONET);
186 skb_reset_mac_header(skb);
187 __skb_pull(skb, 1);
188 skb->dev = dev;
189 dev->stats.rx_packets++;
190 dev->stats.rx_bytes += skb->len;
191
192 netif_rx(skb);
193 }
194 goto resubmit;
195
196 case -ENOENT:
197 case -ECONNRESET:
198 case -ESHUTDOWN:
199 req = NULL;
200 break;
201
202 case -EOVERFLOW:
203 dev->stats.rx_over_errors++;
204 dev_dbg(&dev->dev, "RX overflow\n");
205 break;
206
207 case -EILSEQ:
208 dev->stats.rx_crc_errors++;
209 break;
210 }
211
212 dev->stats.rx_errors++;
213 resubmit:
214 if (page)
215 put_page(page);
216 if (req)
217 rx_submit(pnd, req, GFP_ATOMIC);
218 }
219
220 static int usbpn_close(struct net_device *dev);
221
usbpn_open(struct net_device * dev)222 static int usbpn_open(struct net_device *dev)
223 {
224 struct usbpn_dev *pnd = netdev_priv(dev);
225 int err;
226 unsigned i;
227 unsigned num = pnd->data_intf->cur_altsetting->desc.bInterfaceNumber;
228
229 err = usb_set_interface(pnd->usb, num, pnd->active_setting);
230 if (err)
231 return err;
232
233 for (i = 0; i < rxq_size; i++) {
234 struct urb *req = usb_alloc_urb(0, GFP_KERNEL);
235
236 if (!req || rx_submit(pnd, req, GFP_KERNEL)) {
237 usb_free_urb(req);
238 usbpn_close(dev);
239 return -ENOMEM;
240 }
241 pnd->urbs[i] = req;
242 }
243
244 netif_wake_queue(dev);
245 return 0;
246 }
247
usbpn_close(struct net_device * dev)248 static int usbpn_close(struct net_device *dev)
249 {
250 struct usbpn_dev *pnd = netdev_priv(dev);
251 unsigned i;
252 unsigned num = pnd->data_intf->cur_altsetting->desc.bInterfaceNumber;
253
254 netif_stop_queue(dev);
255
256 for (i = 0; i < rxq_size; i++) {
257 struct urb *req = pnd->urbs[i];
258
259 if (!req)
260 continue;
261 usb_kill_urb(req);
262 usb_free_urb(req);
263 pnd->urbs[i] = NULL;
264 }
265
266 return usb_set_interface(pnd->usb, num, !pnd->active_setting);
267 }
268
usbpn_ioctl(struct net_device * dev,struct ifreq * ifr,int cmd)269 static int usbpn_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
270 {
271 struct if_phonet_req *req = (struct if_phonet_req *)ifr;
272
273 switch (cmd) {
274 case SIOCPNGAUTOCONF:
275 req->ifr_phonet_autoconf.device = PN_DEV_PC;
276 return 0;
277 }
278 return -ENOIOCTLCMD;
279 }
280
281 static const struct net_device_ops usbpn_ops = {
282 .ndo_open = usbpn_open,
283 .ndo_stop = usbpn_close,
284 .ndo_start_xmit = usbpn_xmit,
285 .ndo_do_ioctl = usbpn_ioctl,
286 };
287
usbpn_setup(struct net_device * dev)288 static void usbpn_setup(struct net_device *dev)
289 {
290 dev->features = 0;
291 dev->netdev_ops = &usbpn_ops,
292 dev->header_ops = &phonet_header_ops;
293 dev->type = ARPHRD_PHONET;
294 dev->flags = IFF_POINTOPOINT | IFF_NOARP;
295 dev->mtu = PHONET_MAX_MTU;
296 dev->min_mtu = PHONET_MIN_MTU;
297 dev->max_mtu = PHONET_MAX_MTU;
298 dev->hard_header_len = 1;
299 dev->dev_addr[0] = PN_MEDIA_USB;
300 dev->addr_len = 1;
301 dev->tx_queue_len = 3;
302
303 dev->needs_free_netdev = true;
304 }
305
306 /*
307 * USB driver callbacks
308 */
309 static const struct usb_device_id usbpn_ids[] = {
310 {
311 .match_flags = USB_DEVICE_ID_MATCH_VENDOR
312 | USB_DEVICE_ID_MATCH_INT_CLASS
313 | USB_DEVICE_ID_MATCH_INT_SUBCLASS,
314 .idVendor = 0x0421, /* Nokia */
315 .bInterfaceClass = USB_CLASS_COMM,
316 .bInterfaceSubClass = 0xFE,
317 },
318 { },
319 };
320
321 MODULE_DEVICE_TABLE(usb, usbpn_ids);
322
323 static struct usb_driver usbpn_driver;
324
usbpn_probe(struct usb_interface * intf,const struct usb_device_id * id)325 static int usbpn_probe(struct usb_interface *intf, const struct usb_device_id *id)
326 {
327 static const char ifname[] = "usbpn%d";
328 const struct usb_cdc_union_desc *union_header = NULL;
329 const struct usb_host_interface *data_desc;
330 struct usb_interface *data_intf;
331 struct usb_device *usbdev = interface_to_usbdev(intf);
332 struct net_device *dev;
333 struct usbpn_dev *pnd;
334 u8 *data;
335 int phonet = 0;
336 int len, err;
337 struct usb_cdc_parsed_header hdr;
338
339 data = intf->altsetting->extra;
340 len = intf->altsetting->extralen;
341 cdc_parse_cdc_header(&hdr, intf, data, len);
342 union_header = hdr.usb_cdc_union_desc;
343 phonet = hdr.phonet_magic_present;
344
345 if (!union_header || !phonet)
346 return -EINVAL;
347
348 data_intf = usb_ifnum_to_if(usbdev, union_header->bSlaveInterface0);
349 if (data_intf == NULL)
350 return -ENODEV;
351 /* Data interface has one inactive and one active setting */
352 if (data_intf->num_altsetting != 2)
353 return -EINVAL;
354 if (data_intf->altsetting[0].desc.bNumEndpoints == 0 &&
355 data_intf->altsetting[1].desc.bNumEndpoints == 2)
356 data_desc = data_intf->altsetting + 1;
357 else
358 if (data_intf->altsetting[0].desc.bNumEndpoints == 2 &&
359 data_intf->altsetting[1].desc.bNumEndpoints == 0)
360 data_desc = data_intf->altsetting;
361 else
362 return -EINVAL;
363
364 dev = alloc_netdev(sizeof(*pnd) + sizeof(pnd->urbs[0]) * rxq_size,
365 ifname, NET_NAME_UNKNOWN, usbpn_setup);
366 if (!dev)
367 return -ENOMEM;
368
369 pnd = netdev_priv(dev);
370 SET_NETDEV_DEV(dev, &intf->dev);
371
372 pnd->dev = dev;
373 pnd->usb = usbdev;
374 pnd->intf = intf;
375 pnd->data_intf = data_intf;
376 spin_lock_init(&pnd->tx_lock);
377 spin_lock_init(&pnd->rx_lock);
378 /* Endpoints */
379 if (usb_pipein(data_desc->endpoint[0].desc.bEndpointAddress)) {
380 pnd->rx_pipe = usb_rcvbulkpipe(usbdev,
381 data_desc->endpoint[0].desc.bEndpointAddress);
382 pnd->tx_pipe = usb_sndbulkpipe(usbdev,
383 data_desc->endpoint[1].desc.bEndpointAddress);
384 } else {
385 pnd->rx_pipe = usb_rcvbulkpipe(usbdev,
386 data_desc->endpoint[1].desc.bEndpointAddress);
387 pnd->tx_pipe = usb_sndbulkpipe(usbdev,
388 data_desc->endpoint[0].desc.bEndpointAddress);
389 }
390 pnd->active_setting = data_desc - data_intf->altsetting;
391
392 err = usb_driver_claim_interface(&usbpn_driver, data_intf, pnd);
393 if (err)
394 goto out;
395
396 /* Force inactive mode until the network device is brought UP */
397 usb_set_interface(usbdev, union_header->bSlaveInterface0,
398 !pnd->active_setting);
399 usb_set_intfdata(intf, pnd);
400
401 err = register_netdev(dev);
402 if (err) {
403 usb_driver_release_interface(&usbpn_driver, data_intf);
404 goto out;
405 }
406
407 dev_dbg(&dev->dev, "USB CDC Phonet device found\n");
408 return 0;
409
410 out:
411 usb_set_intfdata(intf, NULL);
412 free_netdev(dev);
413 return err;
414 }
415
usbpn_disconnect(struct usb_interface * intf)416 static void usbpn_disconnect(struct usb_interface *intf)
417 {
418 struct usbpn_dev *pnd = usb_get_intfdata(intf);
419
420 if (pnd->disconnected)
421 return;
422
423 pnd->disconnected = 1;
424 usb_driver_release_interface(&usbpn_driver,
425 (pnd->intf == intf) ? pnd->data_intf : pnd->intf);
426 unregister_netdev(pnd->dev);
427 }
428
429 static struct usb_driver usbpn_driver = {
430 .name = "cdc_phonet",
431 .probe = usbpn_probe,
432 .disconnect = usbpn_disconnect,
433 .id_table = usbpn_ids,
434 .disable_hub_initiated_lpm = 1,
435 };
436
437 module_usb_driver(usbpn_driver);
438
439 MODULE_AUTHOR("Remi Denis-Courmont");
440 MODULE_DESCRIPTION("USB CDC Phonet host interface");
441 MODULE_LICENSE("GPL");
442
