1 /*
2 * ipheth.c - Apple iPhone USB Ethernet driver
3 *
4 * Copyright (c) 2009 Diego Giagio <diego@giagio.com>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of GIAGIO.COM nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * Alternatively, provided that this notice is retained in full, this
20 * software may be distributed under the terms of the GNU General
21 * Public License ("GPL") version 2, in which case the provisions of the
22 * GPL apply INSTEAD OF those given above.
23 *
24 * The provided data structures and external interfaces from this code
25 * are not restricted to be used by modules with a GPL compatible license.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
30 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
31 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
32 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
33 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
37 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
38 * DAMAGE.
39 *
40 *
41 * Attention: iPhone device must be paired, otherwise it won't respond to our
42 * driver. For more info: http://giagio.com/wiki/moin.cgi/iPhoneEthernetDriver
43 *
44 */
45
46 #include <linux/kernel.h>
47 #include <linux/errno.h>
48 #include <linux/slab.h>
49 #include <linux/module.h>
50 #include <linux/netdevice.h>
51 #include <linux/etherdevice.h>
52 #include <linux/ethtool.h>
53 #include <linux/usb.h>
54 #include <linux/workqueue.h>
55
56 #define USB_VENDOR_APPLE 0x05ac
57
58 #define IPHETH_USBINTF_CLASS 255
59 #define IPHETH_USBINTF_SUBCLASS 253
60 #define IPHETH_USBINTF_PROTO 1
61
62 #define IPHETH_BUF_SIZE 1514
63 #define IPHETH_IP_ALIGN 2 /* padding at front of URB */
64 #define IPHETH_TX_TIMEOUT (5 * HZ)
65
66 #define IPHETH_INTFNUM 2
67 #define IPHETH_ALT_INTFNUM 1
68
69 #define IPHETH_CTRL_ENDP 0x00
70 #define IPHETH_CTRL_BUF_SIZE 0x40
71 #define IPHETH_CTRL_TIMEOUT (5 * HZ)
72
73 #define IPHETH_CMD_GET_MACADDR 0x00
74 #define IPHETH_CMD_CARRIER_CHECK 0x45
75
76 #define IPHETH_CARRIER_CHECK_TIMEOUT round_jiffies_relative(1 * HZ)
77 #define IPHETH_CARRIER_ON 0x04
78
79 static const struct usb_device_id ipheth_table[] = {
80 { USB_VENDOR_AND_INTERFACE_INFO(USB_VENDOR_APPLE, IPHETH_USBINTF_CLASS,
81 IPHETH_USBINTF_SUBCLASS,
82 IPHETH_USBINTF_PROTO) },
83 { }
84 };
85 MODULE_DEVICE_TABLE(usb, ipheth_table);
86
87 struct ipheth_device {
88 struct usb_device *udev;
89 struct usb_interface *intf;
90 struct net_device *net;
91 struct urb *tx_urb;
92 struct urb *rx_urb;
93 unsigned char *tx_buf;
94 unsigned char *rx_buf;
95 unsigned char *ctrl_buf;
96 u8 bulk_in;
97 u8 bulk_out;
98 struct delayed_work carrier_work;
99 bool confirmed_pairing;
100 };
101
102 static int ipheth_rx_submit(struct ipheth_device *dev, gfp_t mem_flags);
103
ipheth_alloc_urbs(struct ipheth_device * iphone)104 static int ipheth_alloc_urbs(struct ipheth_device *iphone)
105 {
106 struct urb *tx_urb = NULL;
107 struct urb *rx_urb = NULL;
108 u8 *tx_buf = NULL;
109 u8 *rx_buf = NULL;
110
111 tx_urb = usb_alloc_urb(0, GFP_KERNEL);
112 if (tx_urb == NULL)
113 goto error_nomem;
114
115 rx_urb = usb_alloc_urb(0, GFP_KERNEL);
116 if (rx_urb == NULL)
117 goto free_tx_urb;
118
119 tx_buf = usb_alloc_coherent(iphone->udev, IPHETH_BUF_SIZE,
120 GFP_KERNEL, &tx_urb->transfer_dma);
121 if (tx_buf == NULL)
122 goto free_rx_urb;
123
124 rx_buf = usb_alloc_coherent(iphone->udev, IPHETH_BUF_SIZE + IPHETH_IP_ALIGN,
125 GFP_KERNEL, &rx_urb->transfer_dma);
126 if (rx_buf == NULL)
127 goto free_tx_buf;
128
129
130 iphone->tx_urb = tx_urb;
131 iphone->rx_urb = rx_urb;
132 iphone->tx_buf = tx_buf;
133 iphone->rx_buf = rx_buf;
134 return 0;
135
136 free_tx_buf:
137 usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, tx_buf,
138 tx_urb->transfer_dma);
139 free_rx_urb:
140 usb_free_urb(rx_urb);
141 free_tx_urb:
142 usb_free_urb(tx_urb);
143 error_nomem:
144 return -ENOMEM;
145 }
146
ipheth_free_urbs(struct ipheth_device * iphone)147 static void ipheth_free_urbs(struct ipheth_device *iphone)
148 {
149 usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE + IPHETH_IP_ALIGN, iphone->rx_buf,
150 iphone->rx_urb->transfer_dma);
151 usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, iphone->tx_buf,
152 iphone->tx_urb->transfer_dma);
153 usb_free_urb(iphone->rx_urb);
154 usb_free_urb(iphone->tx_urb);
155 }
156
ipheth_kill_urbs(struct ipheth_device * dev)157 static void ipheth_kill_urbs(struct ipheth_device *dev)
158 {
159 usb_kill_urb(dev->tx_urb);
160 usb_kill_urb(dev->rx_urb);
161 }
162
ipheth_rcvbulk_callback(struct urb * urb)163 static void ipheth_rcvbulk_callback(struct urb *urb)
164 {
165 struct ipheth_device *dev;
166 struct sk_buff *skb;
167 int status;
168 char *buf;
169 int len;
170
171 dev = urb->context;
172 if (dev == NULL)
173 return;
174
175 status = urb->status;
176 switch (status) {
177 case -ENOENT:
178 case -ECONNRESET:
179 case -ESHUTDOWN:
180 case -EPROTO:
181 return;
182 case 0:
183 break;
184 default:
185 dev_err(&dev->intf->dev, "%s: urb status: %d\n",
186 __func__, status);
187 return;
188 }
189
190 if (urb->actual_length <= IPHETH_IP_ALIGN) {
191 dev->net->stats.rx_length_errors++;
192 return;
193 }
194 len = urb->actual_length - IPHETH_IP_ALIGN;
195 buf = urb->transfer_buffer + IPHETH_IP_ALIGN;
196
197 skb = dev_alloc_skb(len);
198 if (!skb) {
199 dev_err(&dev->intf->dev, "%s: dev_alloc_skb: -ENOMEM\n",
200 __func__);
201 dev->net->stats.rx_dropped++;
202 return;
203 }
204
205 skb_put_data(skb, buf, len);
206 skb->dev = dev->net;
207 skb->protocol = eth_type_trans(skb, dev->net);
208
209 dev->net->stats.rx_packets++;
210 dev->net->stats.rx_bytes += len;
211 dev->confirmed_pairing = true;
212 netif_rx(skb);
213 ipheth_rx_submit(dev, GFP_ATOMIC);
214 }
215
ipheth_sndbulk_callback(struct urb * urb)216 static void ipheth_sndbulk_callback(struct urb *urb)
217 {
218 struct ipheth_device *dev;
219 int status = urb->status;
220
221 dev = urb->context;
222 if (dev == NULL)
223 return;
224
225 if (status != 0 &&
226 status != -ENOENT &&
227 status != -ECONNRESET &&
228 status != -ESHUTDOWN)
229 dev_err(&dev->intf->dev, "%s: urb status: %d\n",
230 __func__, status);
231
232 if (status == 0)
233 netif_wake_queue(dev->net);
234 else
235 // on URB error, trigger immediate poll
236 schedule_delayed_work(&dev->carrier_work, 0);
237 }
238
ipheth_carrier_set(struct ipheth_device * dev)239 static int ipheth_carrier_set(struct ipheth_device *dev)
240 {
241 struct usb_device *udev;
242 int retval;
243
244 if (!dev->confirmed_pairing)
245 return 0;
246
247 udev = dev->udev;
248 retval = usb_control_msg(udev,
249 usb_rcvctrlpipe(udev, IPHETH_CTRL_ENDP),
250 IPHETH_CMD_CARRIER_CHECK, /* request */
251 0xc0, /* request type */
252 0x00, /* value */
253 0x02, /* index */
254 dev->ctrl_buf, IPHETH_CTRL_BUF_SIZE,
255 IPHETH_CTRL_TIMEOUT);
256 if (retval < 0) {
257 dev_err(&dev->intf->dev, "%s: usb_control_msg: %d\n",
258 __func__, retval);
259 return retval;
260 }
261
262 if (dev->ctrl_buf[0] == IPHETH_CARRIER_ON) {
263 netif_carrier_on(dev->net);
264 if (dev->tx_urb->status != -EINPROGRESS)
265 netif_wake_queue(dev->net);
266 } else {
267 netif_carrier_off(dev->net);
268 netif_stop_queue(dev->net);
269 }
270 return 0;
271 }
272
ipheth_carrier_check_work(struct work_struct * work)273 static void ipheth_carrier_check_work(struct work_struct *work)
274 {
275 struct ipheth_device *dev = container_of(work, struct ipheth_device,
276 carrier_work.work);
277
278 ipheth_carrier_set(dev);
279 schedule_delayed_work(&dev->carrier_work, IPHETH_CARRIER_CHECK_TIMEOUT);
280 }
281
ipheth_get_macaddr(struct ipheth_device * dev)282 static int ipheth_get_macaddr(struct ipheth_device *dev)
283 {
284 struct usb_device *udev = dev->udev;
285 struct net_device *net = dev->net;
286 int retval;
287
288 retval = usb_control_msg(udev,
289 usb_rcvctrlpipe(udev, IPHETH_CTRL_ENDP),
290 IPHETH_CMD_GET_MACADDR, /* request */
291 0xc0, /* request type */
292 0x00, /* value */
293 0x02, /* index */
294 dev->ctrl_buf,
295 IPHETH_CTRL_BUF_SIZE,
296 IPHETH_CTRL_TIMEOUT);
297 if (retval < 0) {
298 dev_err(&dev->intf->dev, "%s: usb_control_msg: %d\n",
299 __func__, retval);
300 } else if (retval < ETH_ALEN) {
301 dev_err(&dev->intf->dev,
302 "%s: usb_control_msg: short packet: %d bytes\n",
303 __func__, retval);
304 retval = -EINVAL;
305 } else {
306 memcpy(net->dev_addr, dev->ctrl_buf, ETH_ALEN);
307 retval = 0;
308 }
309
310 return retval;
311 }
312
ipheth_rx_submit(struct ipheth_device * dev,gfp_t mem_flags)313 static int ipheth_rx_submit(struct ipheth_device *dev, gfp_t mem_flags)
314 {
315 struct usb_device *udev = dev->udev;
316 int retval;
317
318 usb_fill_bulk_urb(dev->rx_urb, udev,
319 usb_rcvbulkpipe(udev, dev->bulk_in),
320 dev->rx_buf, IPHETH_BUF_SIZE + IPHETH_IP_ALIGN,
321 ipheth_rcvbulk_callback,
322 dev);
323 dev->rx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
324
325 retval = usb_submit_urb(dev->rx_urb, mem_flags);
326 if (retval)
327 dev_err(&dev->intf->dev, "%s: usb_submit_urb: %d\n",
328 __func__, retval);
329 return retval;
330 }
331
ipheth_open(struct net_device * net)332 static int ipheth_open(struct net_device *net)
333 {
334 struct ipheth_device *dev = netdev_priv(net);
335 struct usb_device *udev = dev->udev;
336 int retval = 0;
337
338 usb_set_interface(udev, IPHETH_INTFNUM, IPHETH_ALT_INTFNUM);
339
340 retval = ipheth_carrier_set(dev);
341 if (retval)
342 return retval;
343
344 retval = ipheth_rx_submit(dev, GFP_KERNEL);
345 if (retval)
346 return retval;
347
348 schedule_delayed_work(&dev->carrier_work, IPHETH_CARRIER_CHECK_TIMEOUT);
349 return retval;
350 }
351
ipheth_close(struct net_device * net)352 static int ipheth_close(struct net_device *net)
353 {
354 struct ipheth_device *dev = netdev_priv(net);
355
356 cancel_delayed_work_sync(&dev->carrier_work);
357 netif_stop_queue(net);
358 return 0;
359 }
360
ipheth_tx(struct sk_buff * skb,struct net_device * net)361 static netdev_tx_t ipheth_tx(struct sk_buff *skb, struct net_device *net)
362 {
363 struct ipheth_device *dev = netdev_priv(net);
364 struct usb_device *udev = dev->udev;
365 int retval;
366
367 /* Paranoid */
368 if (skb->len > IPHETH_BUF_SIZE) {
369 WARN(1, "%s: skb too large: %d bytes\n", __func__, skb->len);
370 dev->net->stats.tx_dropped++;
371 dev_kfree_skb_any(skb);
372 return NETDEV_TX_OK;
373 }
374
375 memcpy(dev->tx_buf, skb->data, skb->len);
376 if (skb->len < IPHETH_BUF_SIZE)
377 memset(dev->tx_buf + skb->len, 0, IPHETH_BUF_SIZE - skb->len);
378
379 usb_fill_bulk_urb(dev->tx_urb, udev,
380 usb_sndbulkpipe(udev, dev->bulk_out),
381 dev->tx_buf, IPHETH_BUF_SIZE,
382 ipheth_sndbulk_callback,
383 dev);
384 dev->tx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
385
386 netif_stop_queue(net);
387 retval = usb_submit_urb(dev->tx_urb, GFP_ATOMIC);
388 if (retval) {
389 dev_err(&dev->intf->dev, "%s: usb_submit_urb: %d\n",
390 __func__, retval);
391 dev->net->stats.tx_errors++;
392 dev_kfree_skb_any(skb);
393 netif_wake_queue(net);
394 } else {
395 dev->net->stats.tx_packets++;
396 dev->net->stats.tx_bytes += skb->len;
397 dev_consume_skb_any(skb);
398 }
399
400 return NETDEV_TX_OK;
401 }
402
ipheth_tx_timeout(struct net_device * net,unsigned int txqueue)403 static void ipheth_tx_timeout(struct net_device *net, unsigned int txqueue)
404 {
405 struct ipheth_device *dev = netdev_priv(net);
406
407 dev_err(&dev->intf->dev, "%s: TX timeout\n", __func__);
408 dev->net->stats.tx_errors++;
409 usb_unlink_urb(dev->tx_urb);
410 }
411
ipheth_ethtool_op_get_link(struct net_device * net)412 static u32 ipheth_ethtool_op_get_link(struct net_device *net)
413 {
414 struct ipheth_device *dev = netdev_priv(net);
415 return netif_carrier_ok(dev->net);
416 }
417
418 static const struct ethtool_ops ops = {
419 .get_link = ipheth_ethtool_op_get_link
420 };
421
422 static const struct net_device_ops ipheth_netdev_ops = {
423 .ndo_open = ipheth_open,
424 .ndo_stop = ipheth_close,
425 .ndo_start_xmit = ipheth_tx,
426 .ndo_tx_timeout = ipheth_tx_timeout,
427 };
428
ipheth_probe(struct usb_interface * intf,const struct usb_device_id * id)429 static int ipheth_probe(struct usb_interface *intf,
430 const struct usb_device_id *id)
431 {
432 struct usb_device *udev = interface_to_usbdev(intf);
433 struct usb_host_interface *hintf;
434 struct usb_endpoint_descriptor *endp;
435 struct ipheth_device *dev;
436 struct net_device *netdev;
437 int i;
438 int retval;
439
440 netdev = alloc_etherdev(sizeof(struct ipheth_device));
441 if (!netdev)
442 return -ENOMEM;
443
444 netdev->netdev_ops = &ipheth_netdev_ops;
445 netdev->watchdog_timeo = IPHETH_TX_TIMEOUT;
446 strscpy(netdev->name, "eth%d", sizeof(netdev->name));
447
448 dev = netdev_priv(netdev);
449 dev->udev = udev;
450 dev->net = netdev;
451 dev->intf = intf;
452 dev->confirmed_pairing = false;
453 /* Set up endpoints */
454 hintf = usb_altnum_to_altsetting(intf, IPHETH_ALT_INTFNUM);
455 if (hintf == NULL) {
456 retval = -ENODEV;
457 dev_err(&intf->dev, "Unable to find alternate settings interface\n");
458 goto err_endpoints;
459 }
460
461 for (i = 0; i < hintf->desc.bNumEndpoints; i++) {
462 endp = &hintf->endpoint[i].desc;
463 if (usb_endpoint_is_bulk_in(endp))
464 dev->bulk_in = endp->bEndpointAddress;
465 else if (usb_endpoint_is_bulk_out(endp))
466 dev->bulk_out = endp->bEndpointAddress;
467 }
468 if (!(dev->bulk_in && dev->bulk_out)) {
469 retval = -ENODEV;
470 dev_err(&intf->dev, "Unable to find endpoints\n");
471 goto err_endpoints;
472 }
473
474 dev->ctrl_buf = kmalloc(IPHETH_CTRL_BUF_SIZE, GFP_KERNEL);
475 if (dev->ctrl_buf == NULL) {
476 retval = -ENOMEM;
477 goto err_alloc_ctrl_buf;
478 }
479
480 retval = ipheth_get_macaddr(dev);
481 if (retval)
482 goto err_get_macaddr;
483
484 INIT_DELAYED_WORK(&dev->carrier_work, ipheth_carrier_check_work);
485
486 retval = ipheth_alloc_urbs(dev);
487 if (retval) {
488 dev_err(&intf->dev, "error allocating urbs: %d\n", retval);
489 goto err_alloc_urbs;
490 }
491
492 usb_set_intfdata(intf, dev);
493
494 SET_NETDEV_DEV(netdev, &intf->dev);
495 netdev->ethtool_ops = &ops;
496
497 retval = register_netdev(netdev);
498 if (retval) {
499 dev_err(&intf->dev, "error registering netdev: %d\n", retval);
500 retval = -EIO;
501 goto err_register_netdev;
502 }
503 // carrier down and transmit queues stopped until packet from device
504 netif_carrier_off(netdev);
505 netif_tx_stop_all_queues(netdev);
506 dev_info(&intf->dev, "Apple iPhone USB Ethernet device attached\n");
507 return 0;
508
509 err_register_netdev:
510 ipheth_free_urbs(dev);
511 err_alloc_urbs:
512 err_get_macaddr:
513 err_alloc_ctrl_buf:
514 kfree(dev->ctrl_buf);
515 err_endpoints:
516 free_netdev(netdev);
517 return retval;
518 }
519
ipheth_disconnect(struct usb_interface * intf)520 static void ipheth_disconnect(struct usb_interface *intf)
521 {
522 struct ipheth_device *dev;
523
524 dev = usb_get_intfdata(intf);
525 if (dev != NULL) {
526 unregister_netdev(dev->net);
527 ipheth_kill_urbs(dev);
528 ipheth_free_urbs(dev);
529 kfree(dev->ctrl_buf);
530 free_netdev(dev->net);
531 }
532 usb_set_intfdata(intf, NULL);
533 dev_info(&intf->dev, "Apple iPhone USB Ethernet now disconnected\n");
534 }
535
536 static struct usb_driver ipheth_driver = {
537 .name = "ipheth",
538 .probe = ipheth_probe,
539 .disconnect = ipheth_disconnect,
540 .id_table = ipheth_table,
541 .disable_hub_initiated_lpm = 1,
542 };
543
544 module_usb_driver(ipheth_driver);
545
546 MODULE_AUTHOR("Diego Giagio <diego@giagio.com>");
547 MODULE_DESCRIPTION("Apple iPhone USB Ethernet driver");
548 MODULE_LICENSE("Dual BSD/GPL");
549