xref: /openbmc/linux/drivers/net/usb/ipheth.c (revision 9c1f8594)
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 
64 #define IPHETH_USBINTF_CLASS    255
65 #define IPHETH_USBINTF_SUBCLASS 253
66 #define IPHETH_USBINTF_PROTO    1
67 
68 #define IPHETH_BUF_SIZE         1516
69 #define IPHETH_IP_ALIGN		2	/* padding at front of URB */
70 #define IPHETH_TX_TIMEOUT       (5 * HZ)
71 
72 #define IPHETH_INTFNUM          2
73 #define IPHETH_ALT_INTFNUM      1
74 
75 #define IPHETH_CTRL_ENDP        0x00
76 #define IPHETH_CTRL_BUF_SIZE    0x40
77 #define IPHETH_CTRL_TIMEOUT     (5 * HZ)
78 
79 #define IPHETH_CMD_GET_MACADDR   0x00
80 #define IPHETH_CMD_CARRIER_CHECK 0x45
81 
82 #define IPHETH_CARRIER_CHECK_TIMEOUT round_jiffies_relative(1 * HZ)
83 #define IPHETH_CARRIER_ON       0x04
84 
85 static struct usb_device_id ipheth_table[] = {
86 	{ USB_DEVICE_AND_INTERFACE_INFO(
87 		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE,
88 		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
89 		IPHETH_USBINTF_PROTO) },
90 	{ USB_DEVICE_AND_INTERFACE_INFO(
91 		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_3G,
92 		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
93 		IPHETH_USBINTF_PROTO) },
94 	{ USB_DEVICE_AND_INTERFACE_INFO(
95 		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_3GS,
96 		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
97 		IPHETH_USBINTF_PROTO) },
98 	{ USB_DEVICE_AND_INTERFACE_INFO(
99 		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_4,
100 		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
101 		IPHETH_USBINTF_PROTO) },
102 	{ USB_DEVICE_AND_INTERFACE_INFO(
103 		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_4_VZW,
104 		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
105 		IPHETH_USBINTF_PROTO) },
106 	{ }
107 };
108 MODULE_DEVICE_TABLE(usb, ipheth_table);
109 
110 struct ipheth_device {
111 	struct usb_device *udev;
112 	struct usb_interface *intf;
113 	struct net_device *net;
114 	struct sk_buff *tx_skb;
115 	struct urb *tx_urb;
116 	struct urb *rx_urb;
117 	unsigned char *tx_buf;
118 	unsigned char *rx_buf;
119 	unsigned char *ctrl_buf;
120 	u8 bulk_in;
121 	u8 bulk_out;
122 	struct delayed_work carrier_work;
123 };
124 
125 static int ipheth_rx_submit(struct ipheth_device *dev, gfp_t mem_flags);
126 
127 static int ipheth_alloc_urbs(struct ipheth_device *iphone)
128 {
129 	struct urb *tx_urb = NULL;
130 	struct urb *rx_urb = NULL;
131 	u8 *tx_buf = NULL;
132 	u8 *rx_buf = NULL;
133 
134 	tx_urb = usb_alloc_urb(0, GFP_KERNEL);
135 	if (tx_urb == NULL)
136 		goto error_nomem;
137 
138 	rx_urb = usb_alloc_urb(0, GFP_KERNEL);
139 	if (rx_urb == NULL)
140 		goto free_tx_urb;
141 
142 	tx_buf = usb_alloc_coherent(iphone->udev, IPHETH_BUF_SIZE,
143 				    GFP_KERNEL, &tx_urb->transfer_dma);
144 	if (tx_buf == NULL)
145 		goto free_rx_urb;
146 
147 	rx_buf = usb_alloc_coherent(iphone->udev, IPHETH_BUF_SIZE,
148 				    GFP_KERNEL, &rx_urb->transfer_dma);
149 	if (rx_buf == NULL)
150 		goto free_tx_buf;
151 
152 
153 	iphone->tx_urb = tx_urb;
154 	iphone->rx_urb = rx_urb;
155 	iphone->tx_buf = tx_buf;
156 	iphone->rx_buf = rx_buf;
157 	return 0;
158 
159 free_tx_buf:
160 	usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, tx_buf,
161 			  tx_urb->transfer_dma);
162 free_rx_urb:
163 	usb_free_urb(rx_urb);
164 free_tx_urb:
165 	usb_free_urb(tx_urb);
166 error_nomem:
167 	return -ENOMEM;
168 }
169 
170 static void ipheth_free_urbs(struct ipheth_device *iphone)
171 {
172 	usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, iphone->rx_buf,
173 			  iphone->rx_urb->transfer_dma);
174 	usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, iphone->tx_buf,
175 			  iphone->tx_urb->transfer_dma);
176 	usb_free_urb(iphone->rx_urb);
177 	usb_free_urb(iphone->tx_urb);
178 }
179 
180 static void ipheth_kill_urbs(struct ipheth_device *dev)
181 {
182 	usb_kill_urb(dev->tx_urb);
183 	usb_kill_urb(dev->rx_urb);
184 }
185 
186 static void ipheth_rcvbulk_callback(struct urb *urb)
187 {
188 	struct ipheth_device *dev;
189 	struct sk_buff *skb;
190 	int status;
191 	char *buf;
192 	int len;
193 
194 	dev = urb->context;
195 	if (dev == NULL)
196 		return;
197 
198 	status = urb->status;
199 	switch (status) {
200 	case -ENOENT:
201 	case -ECONNRESET:
202 	case -ESHUTDOWN:
203 		return;
204 	case 0:
205 		break;
206 	default:
207 		err("%s: urb status: %d", __func__, status);
208 		return;
209 	}
210 
211 	if (urb->actual_length <= IPHETH_IP_ALIGN) {
212 		dev->net->stats.rx_length_errors++;
213 		return;
214 	}
215 	len = urb->actual_length - IPHETH_IP_ALIGN;
216 	buf = urb->transfer_buffer + IPHETH_IP_ALIGN;
217 
218 	skb = dev_alloc_skb(len);
219 	if (!skb) {
220 		err("%s: dev_alloc_skb: -ENOMEM", __func__);
221 		dev->net->stats.rx_dropped++;
222 		return;
223 	}
224 
225 	memcpy(skb_put(skb, len), buf, len);
226 	skb->dev = dev->net;
227 	skb->protocol = eth_type_trans(skb, dev->net);
228 
229 	dev->net->stats.rx_packets++;
230 	dev->net->stats.rx_bytes += len;
231 
232 	netif_rx(skb);
233 	ipheth_rx_submit(dev, GFP_ATOMIC);
234 }
235 
236 static void ipheth_sndbulk_callback(struct urb *urb)
237 {
238 	struct ipheth_device *dev;
239 	int status = urb->status;
240 
241 	dev = urb->context;
242 	if (dev == NULL)
243 		return;
244 
245 	if (status != 0 &&
246 	    status != -ENOENT &&
247 	    status != -ECONNRESET &&
248 	    status != -ESHUTDOWN)
249 		err("%s: urb status: %d", __func__, status);
250 
251 	dev_kfree_skb_irq(dev->tx_skb);
252 	netif_wake_queue(dev->net);
253 }
254 
255 static int ipheth_carrier_set(struct ipheth_device *dev)
256 {
257 	struct usb_device *udev = dev->udev;
258 	int retval;
259 
260 	retval = usb_control_msg(udev,
261 			usb_rcvctrlpipe(udev, IPHETH_CTRL_ENDP),
262 			IPHETH_CMD_CARRIER_CHECK, /* request */
263 			0xc0, /* request type */
264 			0x00, /* value */
265 			0x02, /* index */
266 			dev->ctrl_buf, IPHETH_CTRL_BUF_SIZE,
267 			IPHETH_CTRL_TIMEOUT);
268 	if (retval < 0) {
269 		err("%s: usb_control_msg: %d", __func__, retval);
270 		return retval;
271 	}
272 
273 	if (dev->ctrl_buf[0] == IPHETH_CARRIER_ON)
274 		netif_carrier_on(dev->net);
275 	else
276 		netif_carrier_off(dev->net);
277 
278 	return 0;
279 }
280 
281 static void ipheth_carrier_check_work(struct work_struct *work)
282 {
283 	struct ipheth_device *dev = container_of(work, struct ipheth_device,
284 						 carrier_work.work);
285 
286 	ipheth_carrier_set(dev);
287 	schedule_delayed_work(&dev->carrier_work, IPHETH_CARRIER_CHECK_TIMEOUT);
288 }
289 
290 static int ipheth_get_macaddr(struct ipheth_device *dev)
291 {
292 	struct usb_device *udev = dev->udev;
293 	struct net_device *net = dev->net;
294 	int retval;
295 
296 	retval = usb_control_msg(udev,
297 				 usb_rcvctrlpipe(udev, IPHETH_CTRL_ENDP),
298 				 IPHETH_CMD_GET_MACADDR, /* request */
299 				 0xc0, /* request type */
300 				 0x00, /* value */
301 				 0x02, /* index */
302 				 dev->ctrl_buf,
303 				 IPHETH_CTRL_BUF_SIZE,
304 				 IPHETH_CTRL_TIMEOUT);
305 	if (retval < 0) {
306 		err("%s: usb_control_msg: %d", __func__, retval);
307 	} else if (retval < ETH_ALEN) {
308 		err("%s: usb_control_msg: short packet: %d bytes",
309 			__func__, retval);
310 		retval = -EINVAL;
311 	} else {
312 		memcpy(net->dev_addr, dev->ctrl_buf, ETH_ALEN);
313 		retval = 0;
314 	}
315 
316 	return retval;
317 }
318 
319 static int ipheth_rx_submit(struct ipheth_device *dev, gfp_t mem_flags)
320 {
321 	struct usb_device *udev = dev->udev;
322 	int retval;
323 
324 	usb_fill_bulk_urb(dev->rx_urb, udev,
325 			  usb_rcvbulkpipe(udev, dev->bulk_in),
326 			  dev->rx_buf, IPHETH_BUF_SIZE,
327 			  ipheth_rcvbulk_callback,
328 			  dev);
329 	dev->rx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
330 
331 	retval = usb_submit_urb(dev->rx_urb, mem_flags);
332 	if (retval)
333 		err("%s: usb_submit_urb: %d", __func__, retval);
334 	return retval;
335 }
336 
337 static int ipheth_open(struct net_device *net)
338 {
339 	struct ipheth_device *dev = netdev_priv(net);
340 	struct usb_device *udev = dev->udev;
341 	int retval = 0;
342 
343 	usb_set_interface(udev, IPHETH_INTFNUM, IPHETH_ALT_INTFNUM);
344 
345 	retval = ipheth_carrier_set(dev);
346 	if (retval)
347 		return retval;
348 
349 	retval = ipheth_rx_submit(dev, GFP_KERNEL);
350 	if (retval)
351 		return retval;
352 
353 	schedule_delayed_work(&dev->carrier_work, IPHETH_CARRIER_CHECK_TIMEOUT);
354 	netif_start_queue(net);
355 	return retval;
356 }
357 
358 static int ipheth_close(struct net_device *net)
359 {
360 	struct ipheth_device *dev = netdev_priv(net);
361 
362 	cancel_delayed_work_sync(&dev->carrier_work);
363 	netif_stop_queue(net);
364 	return 0;
365 }
366 
367 static int ipheth_tx(struct sk_buff *skb, struct net_device *net)
368 {
369 	struct ipheth_device *dev = netdev_priv(net);
370 	struct usb_device *udev = dev->udev;
371 	int retval;
372 
373 	/* Paranoid */
374 	if (skb->len > IPHETH_BUF_SIZE) {
375 		WARN(1, "%s: skb too large: %d bytes\n", __func__, skb->len);
376 		dev->net->stats.tx_dropped++;
377 		dev_kfree_skb_irq(skb);
378 		return NETDEV_TX_OK;
379 	}
380 
381 	memcpy(dev->tx_buf, skb->data, skb->len);
382 	if (skb->len < IPHETH_BUF_SIZE)
383 		memset(dev->tx_buf + skb->len, 0, IPHETH_BUF_SIZE - skb->len);
384 
385 	usb_fill_bulk_urb(dev->tx_urb, udev,
386 			  usb_sndbulkpipe(udev, dev->bulk_out),
387 			  dev->tx_buf, IPHETH_BUF_SIZE,
388 			  ipheth_sndbulk_callback,
389 			  dev);
390 	dev->tx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
391 
392 	retval = usb_submit_urb(dev->tx_urb, GFP_ATOMIC);
393 	if (retval) {
394 		err("%s: usb_submit_urb: %d", __func__, retval);
395 		dev->net->stats.tx_errors++;
396 		dev_kfree_skb_irq(skb);
397 	} else {
398 		dev->tx_skb = skb;
399 
400 		dev->net->stats.tx_packets++;
401 		dev->net->stats.tx_bytes += skb->len;
402 		netif_stop_queue(net);
403 	}
404 
405 	return NETDEV_TX_OK;
406 }
407 
408 static void ipheth_tx_timeout(struct net_device *net)
409 {
410 	struct ipheth_device *dev = netdev_priv(net);
411 
412 	err("%s: TX timeout", __func__);
413 	dev->net->stats.tx_errors++;
414 	usb_unlink_urb(dev->tx_urb);
415 }
416 
417 static u32 ipheth_ethtool_op_get_link(struct net_device *net)
418 {
419 	struct ipheth_device *dev = netdev_priv(net);
420 	return netif_carrier_ok(dev->net);
421 }
422 
423 static struct ethtool_ops ops = {
424 	.get_link = ipheth_ethtool_op_get_link
425 };
426 
427 static const struct net_device_ops ipheth_netdev_ops = {
428 	.ndo_open = ipheth_open,
429 	.ndo_stop = ipheth_close,
430 	.ndo_start_xmit = ipheth_tx,
431 	.ndo_tx_timeout = ipheth_tx_timeout,
432 };
433 
434 static int ipheth_probe(struct usb_interface *intf,
435 			const struct usb_device_id *id)
436 {
437 	struct usb_device *udev = interface_to_usbdev(intf);
438 	struct usb_host_interface *hintf;
439 	struct usb_endpoint_descriptor *endp;
440 	struct ipheth_device *dev;
441 	struct net_device *netdev;
442 	int i;
443 	int retval;
444 
445 	netdev = alloc_etherdev(sizeof(struct ipheth_device));
446 	if (!netdev)
447 		return -ENOMEM;
448 
449 	netdev->netdev_ops = &ipheth_netdev_ops;
450 	netdev->watchdog_timeo = IPHETH_TX_TIMEOUT;
451 	strcpy(netdev->name, "eth%d");
452 
453 	dev = netdev_priv(netdev);
454 	dev->udev = udev;
455 	dev->net = netdev;
456 	dev->intf = intf;
457 
458 	/* Set up endpoints */
459 	hintf = usb_altnum_to_altsetting(intf, IPHETH_ALT_INTFNUM);
460 	if (hintf == NULL) {
461 		retval = -ENODEV;
462 		err("Unable to find alternate settings interface");
463 		goto err_endpoints;
464 	}
465 
466 	for (i = 0; i < hintf->desc.bNumEndpoints; i++) {
467 		endp = &hintf->endpoint[i].desc;
468 		if (usb_endpoint_is_bulk_in(endp))
469 			dev->bulk_in = endp->bEndpointAddress;
470 		else if (usb_endpoint_is_bulk_out(endp))
471 			dev->bulk_out = endp->bEndpointAddress;
472 	}
473 	if (!(dev->bulk_in && dev->bulk_out)) {
474 		retval = -ENODEV;
475 		err("Unable to find endpoints");
476 		goto err_endpoints;
477 	}
478 
479 	dev->ctrl_buf = kmalloc(IPHETH_CTRL_BUF_SIZE, GFP_KERNEL);
480 	if (dev->ctrl_buf == NULL) {
481 		retval = -ENOMEM;
482 		goto err_alloc_ctrl_buf;
483 	}
484 
485 	retval = ipheth_get_macaddr(dev);
486 	if (retval)
487 		goto err_get_macaddr;
488 
489 	INIT_DELAYED_WORK(&dev->carrier_work, ipheth_carrier_check_work);
490 
491 	retval = ipheth_alloc_urbs(dev);
492 	if (retval) {
493 		err("error allocating urbs: %d", retval);
494 		goto err_alloc_urbs;
495 	}
496 
497 	usb_set_intfdata(intf, dev);
498 
499 	SET_NETDEV_DEV(netdev, &intf->dev);
500 	SET_ETHTOOL_OPS(netdev, &ops);
501 
502 	retval = register_netdev(netdev);
503 	if (retval) {
504 		err("error registering netdev: %d", retval);
505 		retval = -EIO;
506 		goto err_register_netdev;
507 	}
508 
509 	dev_info(&intf->dev, "Apple iPhone USB Ethernet device attached\n");
510 	return 0;
511 
512 err_register_netdev:
513 	ipheth_free_urbs(dev);
514 err_alloc_urbs:
515 err_get_macaddr:
516 err_alloc_ctrl_buf:
517 	kfree(dev->ctrl_buf);
518 err_endpoints:
519 	free_netdev(netdev);
520 	return retval;
521 }
522 
523 static void ipheth_disconnect(struct usb_interface *intf)
524 {
525 	struct ipheth_device *dev;
526 
527 	dev = usb_get_intfdata(intf);
528 	if (dev != NULL) {
529 		unregister_netdev(dev->net);
530 		ipheth_kill_urbs(dev);
531 		ipheth_free_urbs(dev);
532 		kfree(dev->ctrl_buf);
533 		free_netdev(dev->net);
534 	}
535 	usb_set_intfdata(intf, NULL);
536 	dev_info(&intf->dev, "Apple iPhone USB Ethernet now disconnected\n");
537 }
538 
539 static struct usb_driver ipheth_driver = {
540 	.name =		"ipheth",
541 	.probe =	ipheth_probe,
542 	.disconnect =	ipheth_disconnect,
543 	.id_table =	ipheth_table,
544 };
545 
546 static int __init ipheth_init(void)
547 {
548 	int retval;
549 
550 	retval = usb_register(&ipheth_driver);
551 	if (retval) {
552 		err("usb_register failed: %d", retval);
553 		return retval;
554 	}
555 	return 0;
556 }
557 
558 static void __exit ipheth_exit(void)
559 {
560 	usb_deregister(&ipheth_driver);
561 }
562 
563 module_init(ipheth_init);
564 module_exit(ipheth_exit);
565 
566 MODULE_AUTHOR("Diego Giagio <diego@giagio.com>");
567 MODULE_DESCRIPTION("Apple iPhone USB Ethernet driver");
568 MODULE_LICENSE("Dual BSD/GPL");
569