xref: /openbmc/linux/drivers/net/usb/ipheth.c (revision 8ef207d63f8ecc0eae41cded066dd0e0ee170edf)
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 
63 #define IPHETH_USBINTF_CLASS    255
64 #define IPHETH_USBINTF_SUBCLASS 253
65 #define IPHETH_USBINTF_PROTO    1
66 
67 #define IPHETH_BUF_SIZE         1516
68 #define IPHETH_IP_ALIGN		2	/* padding at front of URB */
69 #define IPHETH_TX_TIMEOUT       (5 * HZ)
70 
71 #define IPHETH_INTFNUM          2
72 #define IPHETH_ALT_INTFNUM      1
73 
74 #define IPHETH_CTRL_ENDP        0x00
75 #define IPHETH_CTRL_BUF_SIZE    0x40
76 #define IPHETH_CTRL_TIMEOUT     (5 * HZ)
77 
78 #define IPHETH_CMD_GET_MACADDR   0x00
79 #define IPHETH_CMD_CARRIER_CHECK 0x45
80 
81 #define IPHETH_CARRIER_CHECK_TIMEOUT round_jiffies_relative(1 * HZ)
82 #define IPHETH_CARRIER_ON       0x04
83 
84 static struct usb_device_id ipheth_table[] = {
85 	{ USB_DEVICE_AND_INTERFACE_INFO(
86 		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE,
87 		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
88 		IPHETH_USBINTF_PROTO) },
89 	{ USB_DEVICE_AND_INTERFACE_INFO(
90 		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_3G,
91 		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
92 		IPHETH_USBINTF_PROTO) },
93 	{ USB_DEVICE_AND_INTERFACE_INFO(
94 		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_3GS,
95 		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
96 		IPHETH_USBINTF_PROTO) },
97 	{ USB_DEVICE_AND_INTERFACE_INFO(
98 		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_4,
99 		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
100 		IPHETH_USBINTF_PROTO) },
101 	{ }
102 };
103 MODULE_DEVICE_TABLE(usb, ipheth_table);
104 
105 struct ipheth_device {
106 	struct usb_device *udev;
107 	struct usb_interface *intf;
108 	struct net_device *net;
109 	struct sk_buff *tx_skb;
110 	struct urb *tx_urb;
111 	struct urb *rx_urb;
112 	unsigned char *tx_buf;
113 	unsigned char *rx_buf;
114 	unsigned char *ctrl_buf;
115 	u8 bulk_in;
116 	u8 bulk_out;
117 	struct delayed_work carrier_work;
118 };
119 
120 static int ipheth_rx_submit(struct ipheth_device *dev, gfp_t mem_flags);
121 
122 static int ipheth_alloc_urbs(struct ipheth_device *iphone)
123 {
124 	struct urb *tx_urb = NULL;
125 	struct urb *rx_urb = NULL;
126 	u8 *tx_buf = NULL;
127 	u8 *rx_buf = NULL;
128 
129 	tx_urb = usb_alloc_urb(0, GFP_KERNEL);
130 	if (tx_urb == NULL)
131 		goto error_nomem;
132 
133 	rx_urb = usb_alloc_urb(0, GFP_KERNEL);
134 	if (rx_urb == NULL)
135 		goto free_tx_urb;
136 
137 	tx_buf = usb_alloc_coherent(iphone->udev, IPHETH_BUF_SIZE,
138 				    GFP_KERNEL, &tx_urb->transfer_dma);
139 	if (tx_buf == NULL)
140 		goto free_rx_urb;
141 
142 	rx_buf = usb_alloc_coherent(iphone->udev, IPHETH_BUF_SIZE,
143 				    GFP_KERNEL, &rx_urb->transfer_dma);
144 	if (rx_buf == NULL)
145 		goto free_tx_buf;
146 
147 
148 	iphone->tx_urb = tx_urb;
149 	iphone->rx_urb = rx_urb;
150 	iphone->tx_buf = tx_buf;
151 	iphone->rx_buf = rx_buf;
152 	return 0;
153 
154 free_tx_buf:
155 	usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, tx_buf,
156 			  tx_urb->transfer_dma);
157 free_rx_urb:
158 	usb_free_urb(rx_urb);
159 free_tx_urb:
160 	usb_free_urb(tx_urb);
161 error_nomem:
162 	return -ENOMEM;
163 }
164 
165 static void ipheth_free_urbs(struct ipheth_device *iphone)
166 {
167 	usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, iphone->rx_buf,
168 			  iphone->rx_urb->transfer_dma);
169 	usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, iphone->tx_buf,
170 			  iphone->tx_urb->transfer_dma);
171 	usb_free_urb(iphone->rx_urb);
172 	usb_free_urb(iphone->tx_urb);
173 }
174 
175 static void ipheth_kill_urbs(struct ipheth_device *dev)
176 {
177 	usb_kill_urb(dev->tx_urb);
178 	usb_kill_urb(dev->rx_urb);
179 }
180 
181 static void ipheth_rcvbulk_callback(struct urb *urb)
182 {
183 	struct ipheth_device *dev;
184 	struct sk_buff *skb;
185 	int status;
186 	char *buf;
187 	int len;
188 
189 	dev = urb->context;
190 	if (dev == NULL)
191 		return;
192 
193 	status = urb->status;
194 	switch (status) {
195 	case -ENOENT:
196 	case -ECONNRESET:
197 	case -ESHUTDOWN:
198 		return;
199 	case 0:
200 		break;
201 	default:
202 		err("%s: urb status: %d", __func__, status);
203 		return;
204 	}
205 
206 	if (urb->actual_length <= IPHETH_IP_ALIGN) {
207 		dev->net->stats.rx_length_errors++;
208 		return;
209 	}
210 	len = urb->actual_length - IPHETH_IP_ALIGN;
211 	buf = urb->transfer_buffer + IPHETH_IP_ALIGN;
212 
213 	skb = dev_alloc_skb(len);
214 	if (!skb) {
215 		err("%s: dev_alloc_skb: -ENOMEM", __func__);
216 		dev->net->stats.rx_dropped++;
217 		return;
218 	}
219 
220 	memcpy(skb_put(skb, len), buf, len);
221 	skb->dev = dev->net;
222 	skb->protocol = eth_type_trans(skb, dev->net);
223 
224 	dev->net->stats.rx_packets++;
225 	dev->net->stats.rx_bytes += len;
226 
227 	netif_rx(skb);
228 	ipheth_rx_submit(dev, GFP_ATOMIC);
229 }
230 
231 static void ipheth_sndbulk_callback(struct urb *urb)
232 {
233 	struct ipheth_device *dev;
234 	int status = urb->status;
235 
236 	dev = urb->context;
237 	if (dev == NULL)
238 		return;
239 
240 	if (status != 0 &&
241 	    status != -ENOENT &&
242 	    status != -ECONNRESET &&
243 	    status != -ESHUTDOWN)
244 		err("%s: urb status: %d", __func__, status);
245 
246 	dev_kfree_skb_irq(dev->tx_skb);
247 	netif_wake_queue(dev->net);
248 }
249 
250 static int ipheth_carrier_set(struct ipheth_device *dev)
251 {
252 	struct usb_device *udev = dev->udev;
253 	int retval;
254 
255 	retval = usb_control_msg(udev,
256 			usb_rcvctrlpipe(udev, IPHETH_CTRL_ENDP),
257 			IPHETH_CMD_CARRIER_CHECK, /* request */
258 			0xc0, /* request type */
259 			0x00, /* value */
260 			0x02, /* index */
261 			dev->ctrl_buf, IPHETH_CTRL_BUF_SIZE,
262 			IPHETH_CTRL_TIMEOUT);
263 	if (retval < 0) {
264 		err("%s: usb_control_msg: %d", __func__, retval);
265 		return retval;
266 	}
267 
268 	if (dev->ctrl_buf[0] == IPHETH_CARRIER_ON)
269 		netif_carrier_on(dev->net);
270 	else
271 		netif_carrier_off(dev->net);
272 
273 	return 0;
274 }
275 
276 static void ipheth_carrier_check_work(struct work_struct *work)
277 {
278 	struct ipheth_device *dev = container_of(work, struct ipheth_device,
279 						 carrier_work.work);
280 
281 	ipheth_carrier_set(dev);
282 	schedule_delayed_work(&dev->carrier_work, IPHETH_CARRIER_CHECK_TIMEOUT);
283 }
284 
285 static int ipheth_get_macaddr(struct ipheth_device *dev)
286 {
287 	struct usb_device *udev = dev->udev;
288 	struct net_device *net = dev->net;
289 	int retval;
290 
291 	retval = usb_control_msg(udev,
292 				 usb_rcvctrlpipe(udev, IPHETH_CTRL_ENDP),
293 				 IPHETH_CMD_GET_MACADDR, /* request */
294 				 0xc0, /* request type */
295 				 0x00, /* value */
296 				 0x02, /* index */
297 				 dev->ctrl_buf,
298 				 IPHETH_CTRL_BUF_SIZE,
299 				 IPHETH_CTRL_TIMEOUT);
300 	if (retval < 0) {
301 		err("%s: usb_control_msg: %d", __func__, retval);
302 	} else if (retval < ETH_ALEN) {
303 		err("%s: usb_control_msg: short packet: %d bytes",
304 			__func__, retval);
305 		retval = -EINVAL;
306 	} else {
307 		memcpy(net->dev_addr, dev->ctrl_buf, ETH_ALEN);
308 		retval = 0;
309 	}
310 
311 	return retval;
312 }
313 
314 static int ipheth_rx_submit(struct ipheth_device *dev, gfp_t mem_flags)
315 {
316 	struct usb_device *udev = dev->udev;
317 	int retval;
318 
319 	usb_fill_bulk_urb(dev->rx_urb, udev,
320 			  usb_rcvbulkpipe(udev, dev->bulk_in),
321 			  dev->rx_buf, IPHETH_BUF_SIZE,
322 			  ipheth_rcvbulk_callback,
323 			  dev);
324 	dev->rx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
325 
326 	retval = usb_submit_urb(dev->rx_urb, mem_flags);
327 	if (retval)
328 		err("%s: usb_submit_urb: %d", __func__, retval);
329 	return retval;
330 }
331 
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 	netif_start_queue(net);
350 	return retval;
351 }
352 
353 static int ipheth_close(struct net_device *net)
354 {
355 	struct ipheth_device *dev = netdev_priv(net);
356 
357 	cancel_delayed_work_sync(&dev->carrier_work);
358 	netif_stop_queue(net);
359 	return 0;
360 }
361 
362 static int ipheth_tx(struct sk_buff *skb, struct net_device *net)
363 {
364 	struct ipheth_device *dev = netdev_priv(net);
365 	struct usb_device *udev = dev->udev;
366 	int retval;
367 
368 	/* Paranoid */
369 	if (skb->len > IPHETH_BUF_SIZE) {
370 		WARN(1, "%s: skb too large: %d bytes\n", __func__, skb->len);
371 		dev->net->stats.tx_dropped++;
372 		dev_kfree_skb_irq(skb);
373 		return NETDEV_TX_OK;
374 	}
375 
376 	memcpy(dev->tx_buf, skb->data, skb->len);
377 	if (skb->len < IPHETH_BUF_SIZE)
378 		memset(dev->tx_buf + skb->len, 0, IPHETH_BUF_SIZE - skb->len);
379 
380 	usb_fill_bulk_urb(dev->tx_urb, udev,
381 			  usb_sndbulkpipe(udev, dev->bulk_out),
382 			  dev->tx_buf, IPHETH_BUF_SIZE,
383 			  ipheth_sndbulk_callback,
384 			  dev);
385 	dev->tx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
386 
387 	retval = usb_submit_urb(dev->tx_urb, GFP_ATOMIC);
388 	if (retval) {
389 		err("%s: usb_submit_urb: %d", __func__, retval);
390 		dev->net->stats.tx_errors++;
391 		dev_kfree_skb_irq(skb);
392 	} else {
393 		dev->tx_skb = skb;
394 
395 		dev->net->stats.tx_packets++;
396 		dev->net->stats.tx_bytes += skb->len;
397 		netif_stop_queue(net);
398 	}
399 
400 	return NETDEV_TX_OK;
401 }
402 
403 static void ipheth_tx_timeout(struct net_device *net)
404 {
405 	struct ipheth_device *dev = netdev_priv(net);
406 
407 	err("%s: TX timeout", __func__);
408 	dev->net->stats.tx_errors++;
409 	usb_unlink_urb(dev->tx_urb);
410 }
411 
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 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 
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 	strcpy(netdev->name, "eth%d");
447 
448 	dev = netdev_priv(netdev);
449 	dev->udev = udev;
450 	dev->net = netdev;
451 	dev->intf = intf;
452 
453 	/* Set up endpoints */
454 	hintf = usb_altnum_to_altsetting(intf, IPHETH_ALT_INTFNUM);
455 	if (hintf == NULL) {
456 		retval = -ENODEV;
457 		err("Unable to find alternate settings interface");
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 		err("Unable to find endpoints");
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 		err("error allocating urbs: %d", retval);
489 		goto err_alloc_urbs;
490 	}
491 
492 	usb_set_intfdata(intf, dev);
493 
494 	SET_NETDEV_DEV(netdev, &intf->dev);
495 	SET_ETHTOOL_OPS(netdev, &ops);
496 
497 	retval = register_netdev(netdev);
498 	if (retval) {
499 		err("error registering netdev: %d", retval);
500 		retval = -EIO;
501 		goto err_register_netdev;
502 	}
503 
504 	dev_info(&intf->dev, "Apple iPhone USB Ethernet device attached\n");
505 	return 0;
506 
507 err_register_netdev:
508 	ipheth_free_urbs(dev);
509 err_alloc_urbs:
510 err_get_macaddr:
511 err_alloc_ctrl_buf:
512 	kfree(dev->ctrl_buf);
513 err_endpoints:
514 	free_netdev(netdev);
515 	return retval;
516 }
517 
518 static void ipheth_disconnect(struct usb_interface *intf)
519 {
520 	struct ipheth_device *dev;
521 
522 	dev = usb_get_intfdata(intf);
523 	if (dev != NULL) {
524 		unregister_netdev(dev->net);
525 		ipheth_kill_urbs(dev);
526 		ipheth_free_urbs(dev);
527 		kfree(dev->ctrl_buf);
528 		free_netdev(dev->net);
529 	}
530 	usb_set_intfdata(intf, NULL);
531 	dev_info(&intf->dev, "Apple iPhone USB Ethernet now disconnected\n");
532 }
533 
534 static struct usb_driver ipheth_driver = {
535 	.name =		"ipheth",
536 	.probe =	ipheth_probe,
537 	.disconnect =	ipheth_disconnect,
538 	.id_table =	ipheth_table,
539 };
540 
541 static int __init ipheth_init(void)
542 {
543 	int retval;
544 
545 	retval = usb_register(&ipheth_driver);
546 	if (retval) {
547 		err("usb_register failed: %d", retval);
548 		return retval;
549 	}
550 	return 0;
551 }
552 
553 static void __exit ipheth_exit(void)
554 {
555 	usb_deregister(&ipheth_driver);
556 }
557 
558 module_init(ipheth_init);
559 module_exit(ipheth_exit);
560 
561 MODULE_AUTHOR("Diego Giagio <diego@giagio.com>");
562 MODULE_DESCRIPTION("Apple iPhone USB Ethernet driver");
563 MODULE_LICENSE("Dual BSD/GPL");
564