xref: /linux/drivers/net/usb/ipheth.c (revision d97b46a64674a267bc41c9e16132ee2a98c3347d)
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/init.h>
49 #include <linux/slab.h>
50 #include <linux/module.h>
51 #include <linux/netdevice.h>
52 #include <linux/etherdevice.h>
53 #include <linux/ethtool.h>
54 #include <linux/usb.h>
55 #include <linux/workqueue.h>
56 
57 #define USB_VENDOR_APPLE        0x05ac
58 #define USB_PRODUCT_IPHONE      0x1290
59 #define USB_PRODUCT_IPHONE_3G   0x1292
60 #define USB_PRODUCT_IPHONE_3GS  0x1294
61 #define USB_PRODUCT_IPHONE_4	0x1297
62 #define USB_PRODUCT_IPHONE_4_VZW 0x129c
63 #define USB_PRODUCT_IPHONE_4S	0x12a0
64 
65 #define IPHETH_USBINTF_CLASS    255
66 #define IPHETH_USBINTF_SUBCLASS 253
67 #define IPHETH_USBINTF_PROTO    1
68 
69 #define IPHETH_BUF_SIZE         1516
70 #define IPHETH_IP_ALIGN		2	/* padding at front of URB */
71 #define IPHETH_TX_TIMEOUT       (5 * HZ)
72 
73 #define IPHETH_INTFNUM          2
74 #define IPHETH_ALT_INTFNUM      1
75 
76 #define IPHETH_CTRL_ENDP        0x00
77 #define IPHETH_CTRL_BUF_SIZE    0x40
78 #define IPHETH_CTRL_TIMEOUT     (5 * HZ)
79 
80 #define IPHETH_CMD_GET_MACADDR   0x00
81 #define IPHETH_CMD_CARRIER_CHECK 0x45
82 
83 #define IPHETH_CARRIER_CHECK_TIMEOUT round_jiffies_relative(1 * HZ)
84 #define IPHETH_CARRIER_ON       0x04
85 
86 static struct usb_device_id ipheth_table[] = {
87 	{ USB_DEVICE_AND_INTERFACE_INFO(
88 		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE,
89 		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
90 		IPHETH_USBINTF_PROTO) },
91 	{ USB_DEVICE_AND_INTERFACE_INFO(
92 		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_3G,
93 		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
94 		IPHETH_USBINTF_PROTO) },
95 	{ USB_DEVICE_AND_INTERFACE_INFO(
96 		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_3GS,
97 		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
98 		IPHETH_USBINTF_PROTO) },
99 	{ USB_DEVICE_AND_INTERFACE_INFO(
100 		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_4,
101 		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
102 		IPHETH_USBINTF_PROTO) },
103 	{ USB_DEVICE_AND_INTERFACE_INFO(
104 		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_4_VZW,
105 		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
106 		IPHETH_USBINTF_PROTO) },
107 	{ USB_DEVICE_AND_INTERFACE_INFO(
108 		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_4S,
109 		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
110 		IPHETH_USBINTF_PROTO) },
111 	{ }
112 };
113 MODULE_DEVICE_TABLE(usb, ipheth_table);
114 
115 struct ipheth_device {
116 	struct usb_device *udev;
117 	struct usb_interface *intf;
118 	struct net_device *net;
119 	struct sk_buff *tx_skb;
120 	struct urb *tx_urb;
121 	struct urb *rx_urb;
122 	unsigned char *tx_buf;
123 	unsigned char *rx_buf;
124 	unsigned char *ctrl_buf;
125 	u8 bulk_in;
126 	u8 bulk_out;
127 	struct delayed_work carrier_work;
128 };
129 
130 static int ipheth_rx_submit(struct ipheth_device *dev, gfp_t mem_flags);
131 
132 static int ipheth_alloc_urbs(struct ipheth_device *iphone)
133 {
134 	struct urb *tx_urb = NULL;
135 	struct urb *rx_urb = NULL;
136 	u8 *tx_buf = NULL;
137 	u8 *rx_buf = NULL;
138 
139 	tx_urb = usb_alloc_urb(0, GFP_KERNEL);
140 	if (tx_urb == NULL)
141 		goto error_nomem;
142 
143 	rx_urb = usb_alloc_urb(0, GFP_KERNEL);
144 	if (rx_urb == NULL)
145 		goto free_tx_urb;
146 
147 	tx_buf = usb_alloc_coherent(iphone->udev, IPHETH_BUF_SIZE,
148 				    GFP_KERNEL, &tx_urb->transfer_dma);
149 	if (tx_buf == NULL)
150 		goto free_rx_urb;
151 
152 	rx_buf = usb_alloc_coherent(iphone->udev, IPHETH_BUF_SIZE,
153 				    GFP_KERNEL, &rx_urb->transfer_dma);
154 	if (rx_buf == NULL)
155 		goto free_tx_buf;
156 
157 
158 	iphone->tx_urb = tx_urb;
159 	iphone->rx_urb = rx_urb;
160 	iphone->tx_buf = tx_buf;
161 	iphone->rx_buf = rx_buf;
162 	return 0;
163 
164 free_tx_buf:
165 	usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, tx_buf,
166 			  tx_urb->transfer_dma);
167 free_rx_urb:
168 	usb_free_urb(rx_urb);
169 free_tx_urb:
170 	usb_free_urb(tx_urb);
171 error_nomem:
172 	return -ENOMEM;
173 }
174 
175 static void ipheth_free_urbs(struct ipheth_device *iphone)
176 {
177 	usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, iphone->rx_buf,
178 			  iphone->rx_urb->transfer_dma);
179 	usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, iphone->tx_buf,
180 			  iphone->tx_urb->transfer_dma);
181 	usb_free_urb(iphone->rx_urb);
182 	usb_free_urb(iphone->tx_urb);
183 }
184 
185 static void ipheth_kill_urbs(struct ipheth_device *dev)
186 {
187 	usb_kill_urb(dev->tx_urb);
188 	usb_kill_urb(dev->rx_urb);
189 }
190 
191 static void ipheth_rcvbulk_callback(struct urb *urb)
192 {
193 	struct ipheth_device *dev;
194 	struct sk_buff *skb;
195 	int status;
196 	char *buf;
197 	int len;
198 
199 	dev = urb->context;
200 	if (dev == NULL)
201 		return;
202 
203 	status = urb->status;
204 	switch (status) {
205 	case -ENOENT:
206 	case -ECONNRESET:
207 	case -ESHUTDOWN:
208 		return;
209 	case 0:
210 		break;
211 	default:
212 		dev_err(&dev->intf->dev, "%s: urb status: %d\n",
213 			__func__, status);
214 		return;
215 	}
216 
217 	if (urb->actual_length <= IPHETH_IP_ALIGN) {
218 		dev->net->stats.rx_length_errors++;
219 		return;
220 	}
221 	len = urb->actual_length - IPHETH_IP_ALIGN;
222 	buf = urb->transfer_buffer + IPHETH_IP_ALIGN;
223 
224 	skb = dev_alloc_skb(len);
225 	if (!skb) {
226 		dev_err(&dev->intf->dev, "%s: dev_alloc_skb: -ENOMEM\n",
227 			__func__);
228 		dev->net->stats.rx_dropped++;
229 		return;
230 	}
231 
232 	memcpy(skb_put(skb, len), buf, len);
233 	skb->dev = dev->net;
234 	skb->protocol = eth_type_trans(skb, dev->net);
235 
236 	dev->net->stats.rx_packets++;
237 	dev->net->stats.rx_bytes += len;
238 
239 	netif_rx(skb);
240 	ipheth_rx_submit(dev, GFP_ATOMIC);
241 }
242 
243 static void ipheth_sndbulk_callback(struct urb *urb)
244 {
245 	struct ipheth_device *dev;
246 	int status = urb->status;
247 
248 	dev = urb->context;
249 	if (dev == NULL)
250 		return;
251 
252 	if (status != 0 &&
253 	    status != -ENOENT &&
254 	    status != -ECONNRESET &&
255 	    status != -ESHUTDOWN)
256 		dev_err(&dev->intf->dev, "%s: urb status: %d\n",
257 		__func__, status);
258 
259 	dev_kfree_skb_irq(dev->tx_skb);
260 	netif_wake_queue(dev->net);
261 }
262 
263 static int ipheth_carrier_set(struct ipheth_device *dev)
264 {
265 	struct usb_device *udev = dev->udev;
266 	int retval;
267 
268 	retval = usb_control_msg(udev,
269 			usb_rcvctrlpipe(udev, IPHETH_CTRL_ENDP),
270 			IPHETH_CMD_CARRIER_CHECK, /* request */
271 			0xc0, /* request type */
272 			0x00, /* value */
273 			0x02, /* index */
274 			dev->ctrl_buf, IPHETH_CTRL_BUF_SIZE,
275 			IPHETH_CTRL_TIMEOUT);
276 	if (retval < 0) {
277 		dev_err(&dev->intf->dev, "%s: usb_control_msg: %d\n",
278 			__func__, retval);
279 		return retval;
280 	}
281 
282 	if (dev->ctrl_buf[0] == IPHETH_CARRIER_ON)
283 		netif_carrier_on(dev->net);
284 	else
285 		netif_carrier_off(dev->net);
286 
287 	return 0;
288 }
289 
290 static void ipheth_carrier_check_work(struct work_struct *work)
291 {
292 	struct ipheth_device *dev = container_of(work, struct ipheth_device,
293 						 carrier_work.work);
294 
295 	ipheth_carrier_set(dev);
296 	schedule_delayed_work(&dev->carrier_work, IPHETH_CARRIER_CHECK_TIMEOUT);
297 }
298 
299 static int ipheth_get_macaddr(struct ipheth_device *dev)
300 {
301 	struct usb_device *udev = dev->udev;
302 	struct net_device *net = dev->net;
303 	int retval;
304 
305 	retval = usb_control_msg(udev,
306 				 usb_rcvctrlpipe(udev, IPHETH_CTRL_ENDP),
307 				 IPHETH_CMD_GET_MACADDR, /* request */
308 				 0xc0, /* request type */
309 				 0x00, /* value */
310 				 0x02, /* index */
311 				 dev->ctrl_buf,
312 				 IPHETH_CTRL_BUF_SIZE,
313 				 IPHETH_CTRL_TIMEOUT);
314 	if (retval < 0) {
315 		dev_err(&dev->intf->dev, "%s: usb_control_msg: %d\n",
316 			__func__, retval);
317 	} else if (retval < ETH_ALEN) {
318 		dev_err(&dev->intf->dev,
319 			"%s: usb_control_msg: short packet: %d bytes\n",
320 			__func__, retval);
321 		retval = -EINVAL;
322 	} else {
323 		memcpy(net->dev_addr, dev->ctrl_buf, ETH_ALEN);
324 		retval = 0;
325 	}
326 
327 	return retval;
328 }
329 
330 static int ipheth_rx_submit(struct ipheth_device *dev, gfp_t mem_flags)
331 {
332 	struct usb_device *udev = dev->udev;
333 	int retval;
334 
335 	usb_fill_bulk_urb(dev->rx_urb, udev,
336 			  usb_rcvbulkpipe(udev, dev->bulk_in),
337 			  dev->rx_buf, IPHETH_BUF_SIZE,
338 			  ipheth_rcvbulk_callback,
339 			  dev);
340 	dev->rx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
341 
342 	retval = usb_submit_urb(dev->rx_urb, mem_flags);
343 	if (retval)
344 		dev_err(&dev->intf->dev, "%s: usb_submit_urb: %d\n",
345 			__func__, retval);
346 	return retval;
347 }
348 
349 static int ipheth_open(struct net_device *net)
350 {
351 	struct ipheth_device *dev = netdev_priv(net);
352 	struct usb_device *udev = dev->udev;
353 	int retval = 0;
354 
355 	usb_set_interface(udev, IPHETH_INTFNUM, IPHETH_ALT_INTFNUM);
356 
357 	retval = ipheth_carrier_set(dev);
358 	if (retval)
359 		return retval;
360 
361 	retval = ipheth_rx_submit(dev, GFP_KERNEL);
362 	if (retval)
363 		return retval;
364 
365 	schedule_delayed_work(&dev->carrier_work, IPHETH_CARRIER_CHECK_TIMEOUT);
366 	netif_start_queue(net);
367 	return retval;
368 }
369 
370 static int ipheth_close(struct net_device *net)
371 {
372 	struct ipheth_device *dev = netdev_priv(net);
373 
374 	cancel_delayed_work_sync(&dev->carrier_work);
375 	netif_stop_queue(net);
376 	return 0;
377 }
378 
379 static int ipheth_tx(struct sk_buff *skb, struct net_device *net)
380 {
381 	struct ipheth_device *dev = netdev_priv(net);
382 	struct usb_device *udev = dev->udev;
383 	int retval;
384 
385 	/* Paranoid */
386 	if (skb->len > IPHETH_BUF_SIZE) {
387 		WARN(1, "%s: skb too large: %d bytes\n", __func__, skb->len);
388 		dev->net->stats.tx_dropped++;
389 		dev_kfree_skb_irq(skb);
390 		return NETDEV_TX_OK;
391 	}
392 
393 	memcpy(dev->tx_buf, skb->data, skb->len);
394 	if (skb->len < IPHETH_BUF_SIZE)
395 		memset(dev->tx_buf + skb->len, 0, IPHETH_BUF_SIZE - skb->len);
396 
397 	usb_fill_bulk_urb(dev->tx_urb, udev,
398 			  usb_sndbulkpipe(udev, dev->bulk_out),
399 			  dev->tx_buf, IPHETH_BUF_SIZE,
400 			  ipheth_sndbulk_callback,
401 			  dev);
402 	dev->tx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
403 
404 	retval = usb_submit_urb(dev->tx_urb, GFP_ATOMIC);
405 	if (retval) {
406 		dev_err(&dev->intf->dev, "%s: usb_submit_urb: %d\n",
407 			__func__, retval);
408 		dev->net->stats.tx_errors++;
409 		dev_kfree_skb_irq(skb);
410 	} else {
411 		dev->tx_skb = skb;
412 
413 		dev->net->stats.tx_packets++;
414 		dev->net->stats.tx_bytes += skb->len;
415 		netif_stop_queue(net);
416 	}
417 
418 	return NETDEV_TX_OK;
419 }
420 
421 static void ipheth_tx_timeout(struct net_device *net)
422 {
423 	struct ipheth_device *dev = netdev_priv(net);
424 
425 	dev_err(&dev->intf->dev, "%s: TX timeout\n", __func__);
426 	dev->net->stats.tx_errors++;
427 	usb_unlink_urb(dev->tx_urb);
428 }
429 
430 static u32 ipheth_ethtool_op_get_link(struct net_device *net)
431 {
432 	struct ipheth_device *dev = netdev_priv(net);
433 	return netif_carrier_ok(dev->net);
434 }
435 
436 static const struct ethtool_ops ops = {
437 	.get_link = ipheth_ethtool_op_get_link
438 };
439 
440 static const struct net_device_ops ipheth_netdev_ops = {
441 	.ndo_open = ipheth_open,
442 	.ndo_stop = ipheth_close,
443 	.ndo_start_xmit = ipheth_tx,
444 	.ndo_tx_timeout = ipheth_tx_timeout,
445 };
446 
447 static int ipheth_probe(struct usb_interface *intf,
448 			const struct usb_device_id *id)
449 {
450 	struct usb_device *udev = interface_to_usbdev(intf);
451 	struct usb_host_interface *hintf;
452 	struct usb_endpoint_descriptor *endp;
453 	struct ipheth_device *dev;
454 	struct net_device *netdev;
455 	int i;
456 	int retval;
457 
458 	netdev = alloc_etherdev(sizeof(struct ipheth_device));
459 	if (!netdev)
460 		return -ENOMEM;
461 
462 	netdev->netdev_ops = &ipheth_netdev_ops;
463 	netdev->watchdog_timeo = IPHETH_TX_TIMEOUT;
464 	strcpy(netdev->name, "eth%d");
465 
466 	dev = netdev_priv(netdev);
467 	dev->udev = udev;
468 	dev->net = netdev;
469 	dev->intf = intf;
470 
471 	/* Set up endpoints */
472 	hintf = usb_altnum_to_altsetting(intf, IPHETH_ALT_INTFNUM);
473 	if (hintf == NULL) {
474 		retval = -ENODEV;
475 		dev_err(&intf->dev, "Unable to find alternate settings interface\n");
476 		goto err_endpoints;
477 	}
478 
479 	for (i = 0; i < hintf->desc.bNumEndpoints; i++) {
480 		endp = &hintf->endpoint[i].desc;
481 		if (usb_endpoint_is_bulk_in(endp))
482 			dev->bulk_in = endp->bEndpointAddress;
483 		else if (usb_endpoint_is_bulk_out(endp))
484 			dev->bulk_out = endp->bEndpointAddress;
485 	}
486 	if (!(dev->bulk_in && dev->bulk_out)) {
487 		retval = -ENODEV;
488 		dev_err(&intf->dev, "Unable to find endpoints\n");
489 		goto err_endpoints;
490 	}
491 
492 	dev->ctrl_buf = kmalloc(IPHETH_CTRL_BUF_SIZE, GFP_KERNEL);
493 	if (dev->ctrl_buf == NULL) {
494 		retval = -ENOMEM;
495 		goto err_alloc_ctrl_buf;
496 	}
497 
498 	retval = ipheth_get_macaddr(dev);
499 	if (retval)
500 		goto err_get_macaddr;
501 
502 	INIT_DELAYED_WORK(&dev->carrier_work, ipheth_carrier_check_work);
503 
504 	retval = ipheth_alloc_urbs(dev);
505 	if (retval) {
506 		dev_err(&intf->dev, "error allocating urbs: %d\n", retval);
507 		goto err_alloc_urbs;
508 	}
509 
510 	usb_set_intfdata(intf, dev);
511 
512 	SET_NETDEV_DEV(netdev, &intf->dev);
513 	SET_ETHTOOL_OPS(netdev, &ops);
514 
515 	retval = register_netdev(netdev);
516 	if (retval) {
517 		dev_err(&intf->dev, "error registering netdev: %d\n", retval);
518 		retval = -EIO;
519 		goto err_register_netdev;
520 	}
521 
522 	dev_info(&intf->dev, "Apple iPhone USB Ethernet device attached\n");
523 	return 0;
524 
525 err_register_netdev:
526 	ipheth_free_urbs(dev);
527 err_alloc_urbs:
528 err_get_macaddr:
529 err_alloc_ctrl_buf:
530 	kfree(dev->ctrl_buf);
531 err_endpoints:
532 	free_netdev(netdev);
533 	return retval;
534 }
535 
536 static void ipheth_disconnect(struct usb_interface *intf)
537 {
538 	struct ipheth_device *dev;
539 
540 	dev = usb_get_intfdata(intf);
541 	if (dev != NULL) {
542 		unregister_netdev(dev->net);
543 		ipheth_kill_urbs(dev);
544 		ipheth_free_urbs(dev);
545 		kfree(dev->ctrl_buf);
546 		free_netdev(dev->net);
547 	}
548 	usb_set_intfdata(intf, NULL);
549 	dev_info(&intf->dev, "Apple iPhone USB Ethernet now disconnected\n");
550 }
551 
552 static struct usb_driver ipheth_driver = {
553 	.name =		"ipheth",
554 	.probe =	ipheth_probe,
555 	.disconnect =	ipheth_disconnect,
556 	.id_table =	ipheth_table,
557 	.disable_hub_initiated_lpm = 1,
558 };
559 
560 module_usb_driver(ipheth_driver);
561 
562 MODULE_AUTHOR("Diego Giagio <diego@giagio.com>");
563 MODULE_DESCRIPTION("Apple iPhone USB Ethernet driver");
564 MODULE_LICENSE("Dual BSD/GPL");
565