x86, gcc-4.6: Fix set but not read variables
[firefly-linux-kernel-4.4.55.git] / drivers / net / usb / ipheth.c
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
62 #define IPHETH_USBINTF_CLASS    255
63 #define IPHETH_USBINTF_SUBCLASS 253
64 #define IPHETH_USBINTF_PROTO    1
65
66 #define IPHETH_BUF_SIZE         1516
67 #define IPHETH_TX_TIMEOUT       (5 * HZ)
68
69 #define IPHETH_INTFNUM          2
70 #define IPHETH_ALT_INTFNUM      1
71
72 #define IPHETH_CTRL_ENDP        0x00
73 #define IPHETH_CTRL_BUF_SIZE    0x40
74 #define IPHETH_CTRL_TIMEOUT     (5 * HZ)
75
76 #define IPHETH_CMD_GET_MACADDR   0x00
77 #define IPHETH_CMD_CARRIER_CHECK 0x45
78
79 #define IPHETH_CARRIER_CHECK_TIMEOUT round_jiffies_relative(1 * HZ)
80 #define IPHETH_CARRIER_ON       0x04
81
82 static struct usb_device_id ipheth_table[] = {
83         { USB_DEVICE_AND_INTERFACE_INFO(
84                 USB_VENDOR_APPLE, USB_PRODUCT_IPHONE,
85                 IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
86                 IPHETH_USBINTF_PROTO) },
87         { USB_DEVICE_AND_INTERFACE_INFO(
88                 USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_3G,
89                 IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
90                 IPHETH_USBINTF_PROTO) },
91         { USB_DEVICE_AND_INTERFACE_INFO(
92                 USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_3GS,
93                 IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
94                 IPHETH_USBINTF_PROTO) },
95         { }
96 };
97 MODULE_DEVICE_TABLE(usb, ipheth_table);
98
99 struct ipheth_device {
100         struct usb_device *udev;
101         struct usb_interface *intf;
102         struct net_device *net;
103         struct sk_buff *tx_skb;
104         struct urb *tx_urb;
105         struct urb *rx_urb;
106         unsigned char *tx_buf;
107         unsigned char *rx_buf;
108         unsigned char *ctrl_buf;
109         u8 bulk_in;
110         u8 bulk_out;
111         struct delayed_work carrier_work;
112 };
113
114 static int ipheth_rx_submit(struct ipheth_device *dev, gfp_t mem_flags);
115
116 static int ipheth_alloc_urbs(struct ipheth_device *iphone)
117 {
118         struct urb *tx_urb = NULL;
119         struct urb *rx_urb = NULL;
120         u8 *tx_buf = NULL;
121         u8 *rx_buf = NULL;
122
123         tx_urb = usb_alloc_urb(0, GFP_KERNEL);
124         if (tx_urb == NULL)
125                 goto error_nomem;
126
127         rx_urb = usb_alloc_urb(0, GFP_KERNEL);
128         if (rx_urb == NULL)
129                 goto free_tx_urb;
130
131         tx_buf = usb_alloc_coherent(iphone->udev, IPHETH_BUF_SIZE,
132                                     GFP_KERNEL, &tx_urb->transfer_dma);
133         if (tx_buf == NULL)
134                 goto free_rx_urb;
135
136         rx_buf = usb_alloc_coherent(iphone->udev, IPHETH_BUF_SIZE,
137                                     GFP_KERNEL, &rx_urb->transfer_dma);
138         if (rx_buf == NULL)
139                 goto free_tx_buf;
140
141
142         iphone->tx_urb = tx_urb;
143         iphone->rx_urb = rx_urb;
144         iphone->tx_buf = tx_buf;
145         iphone->rx_buf = rx_buf;
146         return 0;
147
148 free_tx_buf:
149         usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, tx_buf,
150                           tx_urb->transfer_dma);
151 free_rx_urb:
152         usb_free_urb(rx_urb);
153 free_tx_urb:
154         usb_free_urb(tx_urb);
155 error_nomem:
156         return -ENOMEM;
157 }
158
159 static void ipheth_free_urbs(struct ipheth_device *iphone)
160 {
161         usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, iphone->rx_buf,
162                           iphone->rx_urb->transfer_dma);
163         usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, iphone->tx_buf,
164                           iphone->tx_urb->transfer_dma);
165         usb_free_urb(iphone->rx_urb);
166         usb_free_urb(iphone->tx_urb);
167 }
168
169 static void ipheth_kill_urbs(struct ipheth_device *dev)
170 {
171         usb_kill_urb(dev->tx_urb);
172         usb_kill_urb(dev->rx_urb);
173 }
174
175 static void ipheth_rcvbulk_callback(struct urb *urb)
176 {
177         struct ipheth_device *dev;
178         struct sk_buff *skb;
179         int status;
180         char *buf;
181         int len;
182
183         dev = urb->context;
184         if (dev == NULL)
185                 return;
186
187         status = urb->status;
188         switch (status) {
189         case -ENOENT:
190         case -ECONNRESET:
191         case -ESHUTDOWN:
192                 return;
193         case 0:
194                 break;
195         default:
196                 err("%s: urb status: %d", __func__, urb->status);
197                 return;
198         }
199
200         len = urb->actual_length;
201         buf = urb->transfer_buffer;
202
203         skb = dev_alloc_skb(NET_IP_ALIGN + len);
204         if (!skb) {
205                 err("%s: dev_alloc_skb: -ENOMEM", __func__);
206                 dev->net->stats.rx_dropped++;
207                 return;
208         }
209
210         skb_reserve(skb, NET_IP_ALIGN);
211         memcpy(skb_put(skb, len), buf + NET_IP_ALIGN, len - NET_IP_ALIGN);
212         skb->dev = dev->net;
213         skb->protocol = eth_type_trans(skb, dev->net);
214
215         dev->net->stats.rx_packets++;
216         dev->net->stats.rx_bytes += len;
217
218         netif_rx(skb);
219         ipheth_rx_submit(dev, GFP_ATOMIC);
220 }
221
222 static void ipheth_sndbulk_callback(struct urb *urb)
223 {
224         struct ipheth_device *dev;
225
226         dev = urb->context;
227         if (dev == NULL)
228                 return;
229
230         if (urb->status != 0 &&
231             urb->status != -ENOENT &&
232             urb->status != -ECONNRESET &&
233             urb->status != -ESHUTDOWN)
234                 err("%s: urb status: %d", __func__, urb->status);
235
236         dev_kfree_skb_irq(dev->tx_skb);
237         netif_wake_queue(dev->net);
238 }
239
240 static int ipheth_carrier_set(struct ipheth_device *dev)
241 {
242         struct usb_device *udev = dev->udev;
243         int retval;
244
245         retval = usb_control_msg(udev,
246                         usb_rcvctrlpipe(udev, IPHETH_CTRL_ENDP),
247                         IPHETH_CMD_CARRIER_CHECK, /* request */
248                         0xc0, /* request type */
249                         0x00, /* value */
250                         0x02, /* index */
251                         dev->ctrl_buf, IPHETH_CTRL_BUF_SIZE,
252                         IPHETH_CTRL_TIMEOUT);
253         if (retval < 0) {
254                 err("%s: usb_control_msg: %d", __func__, retval);
255                 return retval;
256         }
257
258         if (dev->ctrl_buf[0] == IPHETH_CARRIER_ON)
259                 netif_carrier_on(dev->net);
260         else
261                 netif_carrier_off(dev->net);
262
263         return 0;
264 }
265
266 static void ipheth_carrier_check_work(struct work_struct *work)
267 {
268         struct ipheth_device *dev = container_of(work, struct ipheth_device,
269                                                  carrier_work.work);
270
271         ipheth_carrier_set(dev);
272         schedule_delayed_work(&dev->carrier_work, IPHETH_CARRIER_CHECK_TIMEOUT);
273 }
274
275 static int ipheth_get_macaddr(struct ipheth_device *dev)
276 {
277         struct usb_device *udev = dev->udev;
278         struct net_device *net = dev->net;
279         int retval;
280
281         retval = usb_control_msg(udev,
282                                  usb_rcvctrlpipe(udev, IPHETH_CTRL_ENDP),
283                                  IPHETH_CMD_GET_MACADDR, /* request */
284                                  0xc0, /* request type */
285                                  0x00, /* value */
286                                  0x02, /* index */
287                                  dev->ctrl_buf,
288                                  IPHETH_CTRL_BUF_SIZE,
289                                  IPHETH_CTRL_TIMEOUT);
290         if (retval < 0) {
291                 err("%s: usb_control_msg: %d", __func__, retval);
292         } else if (retval < ETH_ALEN) {
293                 err("%s: usb_control_msg: short packet: %d bytes",
294                         __func__, retval);
295                 retval = -EINVAL;
296         } else {
297                 memcpy(net->dev_addr, dev->ctrl_buf, ETH_ALEN);
298                 retval = 0;
299         }
300
301         return retval;
302 }
303
304 static int ipheth_rx_submit(struct ipheth_device *dev, gfp_t mem_flags)
305 {
306         struct usb_device *udev = dev->udev;
307         int retval;
308
309         usb_fill_bulk_urb(dev->rx_urb, udev,
310                           usb_rcvbulkpipe(udev, dev->bulk_in),
311                           dev->rx_buf, IPHETH_BUF_SIZE,
312                           ipheth_rcvbulk_callback,
313                           dev);
314         dev->rx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
315
316         retval = usb_submit_urb(dev->rx_urb, mem_flags);
317         if (retval)
318                 err("%s: usb_submit_urb: %d", __func__, retval);
319         return retval;
320 }
321
322 static int ipheth_open(struct net_device *net)
323 {
324         struct ipheth_device *dev = netdev_priv(net);
325         struct usb_device *udev = dev->udev;
326         int retval = 0;
327
328         usb_set_interface(udev, IPHETH_INTFNUM, IPHETH_ALT_INTFNUM);
329
330         retval = ipheth_carrier_set(dev);
331         if (retval)
332                 return retval;
333
334         retval = ipheth_rx_submit(dev, GFP_KERNEL);
335         if (retval)
336                 return retval;
337
338         schedule_delayed_work(&dev->carrier_work, IPHETH_CARRIER_CHECK_TIMEOUT);
339         netif_start_queue(net);
340         return retval;
341 }
342
343 static int ipheth_close(struct net_device *net)
344 {
345         struct ipheth_device *dev = netdev_priv(net);
346
347         cancel_delayed_work_sync(&dev->carrier_work);
348         netif_stop_queue(net);
349         return 0;
350 }
351
352 static int ipheth_tx(struct sk_buff *skb, struct net_device *net)
353 {
354         struct ipheth_device *dev = netdev_priv(net);
355         struct usb_device *udev = dev->udev;
356         int retval;
357
358         /* Paranoid */
359         if (skb->len > IPHETH_BUF_SIZE) {
360                 WARN(1, "%s: skb too large: %d bytes", __func__, skb->len);
361                 dev->net->stats.tx_dropped++;
362                 dev_kfree_skb_irq(skb);
363                 return NETDEV_TX_OK;
364         }
365
366         memcpy(dev->tx_buf, skb->data, skb->len);
367         if (skb->len < IPHETH_BUF_SIZE)
368                 memset(dev->tx_buf + skb->len, 0, IPHETH_BUF_SIZE - skb->len);
369
370         usb_fill_bulk_urb(dev->tx_urb, udev,
371                           usb_sndbulkpipe(udev, dev->bulk_out),
372                           dev->tx_buf, IPHETH_BUF_SIZE,
373                           ipheth_sndbulk_callback,
374                           dev);
375         dev->tx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
376
377         retval = usb_submit_urb(dev->tx_urb, GFP_ATOMIC);
378         if (retval) {
379                 err("%s: usb_submit_urb: %d", __func__, retval);
380                 dev->net->stats.tx_errors++;
381                 dev_kfree_skb_irq(skb);
382         } else {
383                 dev->tx_skb = skb;
384
385                 dev->net->stats.tx_packets++;
386                 dev->net->stats.tx_bytes += skb->len;
387                 netif_stop_queue(net);
388         }
389
390         return NETDEV_TX_OK;
391 }
392
393 static void ipheth_tx_timeout(struct net_device *net)
394 {
395         struct ipheth_device *dev = netdev_priv(net);
396
397         err("%s: TX timeout", __func__);
398         dev->net->stats.tx_errors++;
399         usb_unlink_urb(dev->tx_urb);
400 }
401
402 static struct net_device_stats *ipheth_stats(struct net_device *net)
403 {
404         struct ipheth_device *dev = netdev_priv(net);
405         return &dev->net->stats;
406 }
407
408 static u32 ipheth_ethtool_op_get_link(struct net_device *net)
409 {
410         struct ipheth_device *dev = netdev_priv(net);
411         return netif_carrier_ok(dev->net);
412 }
413
414 static struct ethtool_ops ops = {
415         .get_link = ipheth_ethtool_op_get_link
416 };
417
418 static const struct net_device_ops ipheth_netdev_ops = {
419         .ndo_open = &ipheth_open,
420         .ndo_stop = &ipheth_close,
421         .ndo_start_xmit = &ipheth_tx,
422         .ndo_tx_timeout = &ipheth_tx_timeout,
423         .ndo_get_stats = &ipheth_stats,
424 };
425
426 static struct device_type ipheth_type = {
427         .name   = "wwan",
428 };
429
430 static int ipheth_probe(struct usb_interface *intf,
431                         const struct usb_device_id *id)
432 {
433         struct usb_device *udev = interface_to_usbdev(intf);
434         struct usb_host_interface *hintf;
435         struct usb_endpoint_descriptor *endp;
436         struct ipheth_device *dev;
437         struct net_device *netdev;
438         int i;
439         int retval;
440
441         netdev = alloc_etherdev(sizeof(struct ipheth_device));
442         if (!netdev)
443                 return -ENOMEM;
444
445         netdev->netdev_ops = &ipheth_netdev_ops;
446         netdev->watchdog_timeo = IPHETH_TX_TIMEOUT;
447         strcpy(netdev->name, "wwan%d");
448
449         dev = netdev_priv(netdev);
450         dev->udev = udev;
451         dev->net = netdev;
452         dev->intf = intf;
453
454         /* Set up endpoints */
455         hintf = usb_altnum_to_altsetting(intf, IPHETH_ALT_INTFNUM);
456         if (hintf == NULL) {
457                 retval = -ENODEV;
458                 err("Unable to find alternate settings interface");
459                 goto err_endpoints;
460         }
461
462         for (i = 0; i < hintf->desc.bNumEndpoints; i++) {
463                 endp = &hintf->endpoint[i].desc;
464                 if (usb_endpoint_is_bulk_in(endp))
465                         dev->bulk_in = endp->bEndpointAddress;
466                 else if (usb_endpoint_is_bulk_out(endp))
467                         dev->bulk_out = endp->bEndpointAddress;
468         }
469         if (!(dev->bulk_in && dev->bulk_out)) {
470                 retval = -ENODEV;
471                 err("Unable to find endpoints");
472                 goto err_endpoints;
473         }
474
475         dev->ctrl_buf = kmalloc(IPHETH_CTRL_BUF_SIZE, GFP_KERNEL);
476         if (dev->ctrl_buf == NULL) {
477                 retval = -ENOMEM;
478                 goto err_alloc_ctrl_buf;
479         }
480
481         retval = ipheth_get_macaddr(dev);
482         if (retval)
483                 goto err_get_macaddr;
484
485         INIT_DELAYED_WORK(&dev->carrier_work, ipheth_carrier_check_work);
486
487         retval = ipheth_alloc_urbs(dev);
488         if (retval) {
489                 err("error allocating urbs: %d", retval);
490                 goto err_alloc_urbs;
491         }
492
493         usb_set_intfdata(intf, dev);
494
495         SET_NETDEV_DEV(netdev, &intf->dev);
496         SET_ETHTOOL_OPS(netdev, &ops);
497         SET_NETDEV_DEVTYPE(netdev, &ipheth_type);
498
499         retval = register_netdev(netdev);
500         if (retval) {
501                 err("error registering netdev: %d", retval);
502                 retval = -EIO;
503                 goto err_register_netdev;
504         }
505
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
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 };
542
543 static int __init ipheth_init(void)
544 {
545         int retval;
546
547         retval = usb_register(&ipheth_driver);
548         if (retval) {
549                 err("usb_register failed: %d", retval);
550                 return retval;
551         }
552         return 0;
553 }
554
555 static void __exit ipheth_exit(void)
556 {
557         usb_deregister(&ipheth_driver);
558 }
559
560 module_init(ipheth_init);
561 module_exit(ipheth_exit);
562
563 MODULE_AUTHOR("Diego Giagio <diego@giagio.com>");
564 MODULE_DESCRIPTION("Apple iPhone USB Ethernet driver");
565 MODULE_LICENSE("Dual BSD/GPL");