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_IPAD 0x129a
63#define USB_PRODUCT_IPHONE_4_VZW 0x129c
64#define USB_PRODUCT_IPHONE_4S	0x12a0
65
66#define IPHETH_USBINTF_CLASS    255
67#define IPHETH_USBINTF_SUBCLASS 253
68#define IPHETH_USBINTF_PROTO    1
69
70#define IPHETH_BUF_SIZE         1516
71#define IPHETH_IP_ALIGN		2	/* padding at front of URB */
72#define IPHETH_TX_TIMEOUT       (5 * HZ)
73
74#define IPHETH_INTFNUM          2
75#define IPHETH_ALT_INTFNUM      1
76
77#define IPHETH_CTRL_ENDP        0x00
78#define IPHETH_CTRL_BUF_SIZE    0x40
79#define IPHETH_CTRL_TIMEOUT     (5 * HZ)
80
81#define IPHETH_CMD_GET_MACADDR   0x00
82#define IPHETH_CMD_CARRIER_CHECK 0x45
83
84#define IPHETH_CARRIER_CHECK_TIMEOUT round_jiffies_relative(1 * HZ)
85#define IPHETH_CARRIER_ON       0x04
86
87static struct usb_device_id ipheth_table[] = {
88	{ USB_DEVICE_AND_INTERFACE_INFO(
89		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE,
90		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
91		IPHETH_USBINTF_PROTO) },
92	{ USB_DEVICE_AND_INTERFACE_INFO(
93		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_3G,
94		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
95		IPHETH_USBINTF_PROTO) },
96	{ USB_DEVICE_AND_INTERFACE_INFO(
97		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_3GS,
98		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
99		IPHETH_USBINTF_PROTO) },
100	{ USB_DEVICE_AND_INTERFACE_INFO(
101		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_4,
102		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
103		IPHETH_USBINTF_PROTO) },
104	{ USB_DEVICE_AND_INTERFACE_INFO(
105		USB_VENDOR_APPLE, USB_PRODUCT_IPAD,
106		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
107		IPHETH_USBINTF_PROTO) },
108	{ USB_DEVICE_AND_INTERFACE_INFO(
109		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_4_VZW,
110		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
111		IPHETH_USBINTF_PROTO) },
112	{ USB_DEVICE_AND_INTERFACE_INFO(
113		USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_4S,
114		IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
115		IPHETH_USBINTF_PROTO) },
116	{ }
117};
118MODULE_DEVICE_TABLE(usb, ipheth_table);
119
120struct ipheth_device {
121	struct usb_device *udev;
122	struct usb_interface *intf;
123	struct net_device *net;
124	struct sk_buff *tx_skb;
125	struct urb *tx_urb;
126	struct urb *rx_urb;
127	unsigned char *tx_buf;
128	unsigned char *rx_buf;
129	unsigned char *ctrl_buf;
130	u8 bulk_in;
131	u8 bulk_out;
132	struct delayed_work carrier_work;
133};
134
135static int ipheth_rx_submit(struct ipheth_device *dev, gfp_t mem_flags);
136
137static int ipheth_alloc_urbs(struct ipheth_device *iphone)
138{
139	struct urb *tx_urb = NULL;
140	struct urb *rx_urb = NULL;
141	u8 *tx_buf = NULL;
142	u8 *rx_buf = NULL;
143
144	tx_urb = usb_alloc_urb(0, GFP_KERNEL);
145	if (tx_urb == NULL)
146		goto error_nomem;
147
148	rx_urb = usb_alloc_urb(0, GFP_KERNEL);
149	if (rx_urb == NULL)
150		goto free_tx_urb;
151
152	tx_buf = usb_alloc_coherent(iphone->udev, IPHETH_BUF_SIZE,
153				    GFP_KERNEL, &tx_urb->transfer_dma);
154	if (tx_buf == NULL)
155		goto free_rx_urb;
156
157	rx_buf = usb_alloc_coherent(iphone->udev, IPHETH_BUF_SIZE,
158				    GFP_KERNEL, &rx_urb->transfer_dma);
159	if (rx_buf == NULL)
160		goto free_tx_buf;
161
162
163	iphone->tx_urb = tx_urb;
164	iphone->rx_urb = rx_urb;
165	iphone->tx_buf = tx_buf;
166	iphone->rx_buf = rx_buf;
167	return 0;
168
169free_tx_buf:
170	usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, tx_buf,
171			  tx_urb->transfer_dma);
172free_rx_urb:
173	usb_free_urb(rx_urb);
174free_tx_urb:
175	usb_free_urb(tx_urb);
176error_nomem:
177	return -ENOMEM;
178}
179
180static void ipheth_free_urbs(struct ipheth_device *iphone)
181{
182	usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, iphone->rx_buf,
183			  iphone->rx_urb->transfer_dma);
184	usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, iphone->tx_buf,
185			  iphone->tx_urb->transfer_dma);
186	usb_free_urb(iphone->rx_urb);
187	usb_free_urb(iphone->tx_urb);
188}
189
190static void ipheth_kill_urbs(struct ipheth_device *dev)
191{
192	usb_kill_urb(dev->tx_urb);
193	usb_kill_urb(dev->rx_urb);
194}
195
196static void ipheth_rcvbulk_callback(struct urb *urb)
197{
198	struct ipheth_device *dev;
199	struct sk_buff *skb;
200	int status;
201	char *buf;
202	int len;
203
204	dev = urb->context;
205	if (dev == NULL)
206		return;
207
208	status = urb->status;
209	switch (status) {
210	case -ENOENT:
211	case -ECONNRESET:
212	case -ESHUTDOWN:
213		return;
214	case 0:
215		break;
216	default:
217		err("%s: urb status: %d", __func__, status);
218		return;
219	}
220
221	if (urb->actual_length <= IPHETH_IP_ALIGN) {
222		dev->net->stats.rx_length_errors++;
223		return;
224	}
225	len = urb->actual_length - IPHETH_IP_ALIGN;
226	buf = urb->transfer_buffer + IPHETH_IP_ALIGN;
227
228	skb = dev_alloc_skb(len);
229	if (!skb) {
230		err("%s: dev_alloc_skb: -ENOMEM", __func__);
231		dev->net->stats.rx_dropped++;
232		return;
233	}
234
235	memcpy(skb_put(skb, len), buf, len);
236	skb->dev = dev->net;
237	skb->protocol = eth_type_trans(skb, dev->net);
238
239	dev->net->stats.rx_packets++;
240	dev->net->stats.rx_bytes += len;
241
242	netif_rx(skb);
243	ipheth_rx_submit(dev, GFP_ATOMIC);
244}
245
246static void ipheth_sndbulk_callback(struct urb *urb)
247{
248	struct ipheth_device *dev;
249	int status = urb->status;
250
251	dev = urb->context;
252	if (dev == NULL)
253		return;
254
255	if (status != 0 &&
256	    status != -ENOENT &&
257	    status != -ECONNRESET &&
258	    status != -ESHUTDOWN)
259		err("%s: urb status: %d", __func__, status);
260
261	dev_kfree_skb_irq(dev->tx_skb);
262	netif_wake_queue(dev->net);
263}
264
265static int ipheth_carrier_set(struct ipheth_device *dev)
266{
267	struct usb_device *udev = dev->udev;
268	int retval;
269
270	retval = usb_control_msg(udev,
271			usb_rcvctrlpipe(udev, IPHETH_CTRL_ENDP),
272			IPHETH_CMD_CARRIER_CHECK, /* request */
273			0xc0, /* request type */
274			0x00, /* value */
275			0x02, /* index */
276			dev->ctrl_buf, IPHETH_CTRL_BUF_SIZE,
277			IPHETH_CTRL_TIMEOUT);
278	if (retval < 0) {
279		err("%s: usb_control_msg: %d", __func__, retval);
280		return retval;
281	}
282
283	if (dev->ctrl_buf[0] == IPHETH_CARRIER_ON)
284		netif_carrier_on(dev->net);
285	else
286		netif_carrier_off(dev->net);
287
288	return 0;
289}
290
291static void ipheth_carrier_check_work(struct work_struct *work)
292{
293	struct ipheth_device *dev = container_of(work, struct ipheth_device,
294						 carrier_work.work);
295
296	ipheth_carrier_set(dev);
297	schedule_delayed_work(&dev->carrier_work, IPHETH_CARRIER_CHECK_TIMEOUT);
298}
299
300static int ipheth_get_macaddr(struct ipheth_device *dev)
301{
302	struct usb_device *udev = dev->udev;
303	struct net_device *net = dev->net;
304	int retval;
305
306	retval = usb_control_msg(udev,
307				 usb_rcvctrlpipe(udev, IPHETH_CTRL_ENDP),
308				 IPHETH_CMD_GET_MACADDR, /* request */
309				 0xc0, /* request type */
310				 0x00, /* value */
311				 0x02, /* index */
312				 dev->ctrl_buf,
313				 IPHETH_CTRL_BUF_SIZE,
314				 IPHETH_CTRL_TIMEOUT);
315	if (retval < 0) {
316		err("%s: usb_control_msg: %d", __func__, retval);
317	} else if (retval < ETH_ALEN) {
318		err("%s: usb_control_msg: short packet: %d bytes",
319			__func__, retval);
320		retval = -EINVAL;
321	} else {
322		memcpy(net->dev_addr, dev->ctrl_buf, ETH_ALEN);
323		retval = 0;
324	}
325
326	return retval;
327}
328
329static int ipheth_rx_submit(struct ipheth_device *dev, gfp_t mem_flags)
330{
331	struct usb_device *udev = dev->udev;
332	int retval;
333
334	usb_fill_bulk_urb(dev->rx_urb, udev,
335			  usb_rcvbulkpipe(udev, dev->bulk_in),
336			  dev->rx_buf, IPHETH_BUF_SIZE,
337			  ipheth_rcvbulk_callback,
338			  dev);
339	dev->rx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
340
341	retval = usb_submit_urb(dev->rx_urb, mem_flags);
342	if (retval)
343		err("%s: usb_submit_urb: %d", __func__, retval);
344	return retval;
345}
346
347static int ipheth_open(struct net_device *net)
348{
349	struct ipheth_device *dev = netdev_priv(net);
350	struct usb_device *udev = dev->udev;
351	int retval = 0;
352
353	usb_set_interface(udev, IPHETH_INTFNUM, IPHETH_ALT_INTFNUM);
354
355	retval = ipheth_carrier_set(dev);
356	if (retval)
357		return retval;
358
359	retval = ipheth_rx_submit(dev, GFP_KERNEL);
360	if (retval)
361		return retval;
362
363	schedule_delayed_work(&dev->carrier_work, IPHETH_CARRIER_CHECK_TIMEOUT);
364	netif_start_queue(net);
365	return retval;
366}
367
368static int ipheth_close(struct net_device *net)
369{
370	struct ipheth_device *dev = netdev_priv(net);
371
372	cancel_delayed_work_sync(&dev->carrier_work);
373	netif_stop_queue(net);
374	return 0;
375}
376
377static int ipheth_tx(struct sk_buff *skb, struct net_device *net)
378{
379	struct ipheth_device *dev = netdev_priv(net);
380	struct usb_device *udev = dev->udev;
381	int retval;
382
383	/* Paranoid */
384	if (skb->len > IPHETH_BUF_SIZE) {
385		WARN(1, "%s: skb too large: %d bytes\n", __func__, skb->len);
386		dev->net->stats.tx_dropped++;
387		dev_kfree_skb_irq(skb);
388		return NETDEV_TX_OK;
389	}
390
391	memcpy(dev->tx_buf, skb->data, skb->len);
392	if (skb->len < IPHETH_BUF_SIZE)
393		memset(dev->tx_buf + skb->len, 0, IPHETH_BUF_SIZE - skb->len);
394
395	usb_fill_bulk_urb(dev->tx_urb, udev,
396			  usb_sndbulkpipe(udev, dev->bulk_out),
397			  dev->tx_buf, IPHETH_BUF_SIZE,
398			  ipheth_sndbulk_callback,
399			  dev);
400	dev->tx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
401
402	retval = usb_submit_urb(dev->tx_urb, GFP_ATOMIC);
403	if (retval) {
404		err("%s: usb_submit_urb: %d", __func__, retval);
405		dev->net->stats.tx_errors++;
406		dev_kfree_skb_irq(skb);
407	} else {
408		dev->tx_skb = skb;
409
410		dev->net->stats.tx_packets++;
411		dev->net->stats.tx_bytes += skb->len;
412		netif_stop_queue(net);
413	}
414
415	return NETDEV_TX_OK;
416}
417
418static void ipheth_tx_timeout(struct net_device *net)
419{
420	struct ipheth_device *dev = netdev_priv(net);
421
422	err("%s: TX timeout", __func__);
423	dev->net->stats.tx_errors++;
424	usb_unlink_urb(dev->tx_urb);
425}
426
427static u32 ipheth_ethtool_op_get_link(struct net_device *net)
428{
429	struct ipheth_device *dev = netdev_priv(net);
430	return netif_carrier_ok(dev->net);
431}
432
433static const struct ethtool_ops ops = {
434	.get_link = ipheth_ethtool_op_get_link
435};
436
437static const struct net_device_ops ipheth_netdev_ops = {
438	.ndo_open = ipheth_open,
439	.ndo_stop = ipheth_close,
440	.ndo_start_xmit = ipheth_tx,
441	.ndo_tx_timeout = ipheth_tx_timeout,
442};
443
444static int ipheth_probe(struct usb_interface *intf,
445			const struct usb_device_id *id)
446{
447	struct usb_device *udev = interface_to_usbdev(intf);
448	struct usb_host_interface *hintf;
449	struct usb_endpoint_descriptor *endp;
450	struct ipheth_device *dev;
451	struct net_device *netdev;
452	int i;
453	int retval;
454
455	netdev = alloc_etherdev(sizeof(struct ipheth_device));
456	if (!netdev)
457		return -ENOMEM;
458
459	netdev->netdev_ops = &ipheth_netdev_ops;
460	netdev->watchdog_timeo = IPHETH_TX_TIMEOUT;
461	strcpy(netdev->name, "eth%d");
462
463	dev = netdev_priv(netdev);
464	dev->udev = udev;
465	dev->net = netdev;
466	dev->intf = intf;
467
468	/* Set up endpoints */
469	hintf = usb_altnum_to_altsetting(intf, IPHETH_ALT_INTFNUM);
470	if (hintf == NULL) {
471		retval = -ENODEV;
472		err("Unable to find alternate settings interface");
473		goto err_endpoints;
474	}
475
476	for (i = 0; i < hintf->desc.bNumEndpoints; i++) {
477		endp = &hintf->endpoint[i].desc;
478		if (usb_endpoint_is_bulk_in(endp))
479			dev->bulk_in = endp->bEndpointAddress;
480		else if (usb_endpoint_is_bulk_out(endp))
481			dev->bulk_out = endp->bEndpointAddress;
482	}
483	if (!(dev->bulk_in && dev->bulk_out)) {
484		retval = -ENODEV;
485		err("Unable to find endpoints");
486		goto err_endpoints;
487	}
488
489	dev->ctrl_buf = kmalloc(IPHETH_CTRL_BUF_SIZE, GFP_KERNEL);
490	if (dev->ctrl_buf == NULL) {
491		retval = -ENOMEM;
492		goto err_alloc_ctrl_buf;
493	}
494
495	retval = ipheth_get_macaddr(dev);
496	if (retval)
497		goto err_get_macaddr;
498
499	INIT_DELAYED_WORK(&dev->carrier_work, ipheth_carrier_check_work);
500
501	retval = ipheth_alloc_urbs(dev);
502	if (retval) {
503		err("error allocating urbs: %d", retval);
504		goto err_alloc_urbs;
505	}
506
507	usb_set_intfdata(intf, dev);
508
509	SET_NETDEV_DEV(netdev, &intf->dev);
510	SET_ETHTOOL_OPS(netdev, &ops);
511
512	retval = register_netdev(netdev);
513	if (retval) {
514		err("error registering netdev: %d", retval);
515		retval = -EIO;
516		goto err_register_netdev;
517	}
518
519	dev_info(&intf->dev, "Apple iPhone USB Ethernet device attached\n");
520	return 0;
521
522err_register_netdev:
523	ipheth_free_urbs(dev);
524err_alloc_urbs:
525err_get_macaddr:
526err_alloc_ctrl_buf:
527	kfree(dev->ctrl_buf);
528err_endpoints:
529	free_netdev(netdev);
530	return retval;
531}
532
533static void ipheth_disconnect(struct usb_interface *intf)
534{
535	struct ipheth_device *dev;
536
537	dev = usb_get_intfdata(intf);
538	if (dev != NULL) {
539		unregister_netdev(dev->net);
540		ipheth_kill_urbs(dev);
541		ipheth_free_urbs(dev);
542		kfree(dev->ctrl_buf);
543		free_netdev(dev->net);
544	}
545	usb_set_intfdata(intf, NULL);
546	dev_info(&intf->dev, "Apple iPhone USB Ethernet now disconnected\n");
547}
548
549static struct usb_driver ipheth_driver = {
550	.name =		"ipheth",
551	.probe =	ipheth_probe,
552	.disconnect =	ipheth_disconnect,
553	.id_table =	ipheth_table,
554};
555
556module_usb_driver(ipheth_driver);
557
558MODULE_AUTHOR("Diego Giagio <diego@giagio.com>");
559MODULE_DESCRIPTION("Apple iPhone USB Ethernet driver");
560MODULE_LICENSE("Dual BSD/GPL");
561