xref: /openbmc/linux/drivers/net/usb/kaweth.c (revision 94cdda6b)
1 /****************************************************************
2  *
3  *     kaweth.c - driver for KL5KUSB101 based USB->Ethernet
4  *
5  *     (c) 2000 Interlan Communications
6  *     (c) 2000 Stephane Alnet
7  *     (C) 2001 Brad Hards
8  *     (C) 2002 Oliver Neukum
9  *
10  *     Original author: The Zapman <zapman@interlan.net>
11  *     Inspired by, and much credit goes to Michael Rothwell
12  *     <rothwell@interlan.net> for the test equipment, help, and patience
13  *     Based off of (and with thanks to) Petko Manolov's pegaus.c driver.
14  *     Also many thanks to Joel Silverman and Ed Surprenant at Kawasaki
15  *     for providing the firmware and driver resources.
16  *
17  *     This program is free software; you can redistribute it and/or
18  *     modify it under the terms of the GNU General Public License as
19  *     published by the Free Software Foundation; either version 2, or
20  *     (at your option) any later version.
21  *
22  *     This program is distributed in the hope that it will be useful,
23  *     but WITHOUT ANY WARRANTY; without even the implied warranty of
24  *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
25  *     GNU General Public License for more details.
26  *
27  *     You should have received a copy of the GNU General Public License
28  *     along with this program; if not, see <http://www.gnu.org/licenses/>.
29  *
30  ****************************************************************/
31 
32 /* TODO:
33  * Develop test procedures for USB net interfaces
34  * Run test procedures
35  * Fix bugs from previous two steps
36  * Snoop other OSs for any tricks we're not doing
37  * Reduce arbitrary timeouts
38  * Smart multicast support
39  * Temporary MAC change support
40  * Tunable SOFs parameter - ioctl()?
41  * Ethernet stats collection
42  * Code formatting improvements
43  */
44 
45 #include <linux/module.h>
46 #include <linux/slab.h>
47 #include <linux/string.h>
48 #include <linux/delay.h>
49 #include <linux/netdevice.h>
50 #include <linux/etherdevice.h>
51 #include <linux/usb.h>
52 #include <linux/types.h>
53 #include <linux/ethtool.h>
54 #include <linux/dma-mapping.h>
55 #include <linux/wait.h>
56 #include <linux/firmware.h>
57 #include <asm/uaccess.h>
58 #include <asm/byteorder.h>
59 
60 #undef DEBUG
61 
62 #define KAWETH_MTU			1514
63 #define KAWETH_BUF_SIZE			1664
64 #define KAWETH_TX_TIMEOUT		(5 * HZ)
65 #define KAWETH_SCRATCH_SIZE		32
66 #define KAWETH_FIRMWARE_BUF_SIZE	4096
67 #define KAWETH_CONTROL_TIMEOUT		(30000)
68 
69 #define KAWETH_STATUS_BROKEN		0x0000001
70 #define KAWETH_STATUS_CLOSING		0x0000002
71 #define KAWETH_STATUS_SUSPENDING	0x0000004
72 
73 #define KAWETH_STATUS_BLOCKED (KAWETH_STATUS_CLOSING | KAWETH_STATUS_SUSPENDING)
74 
75 #define KAWETH_PACKET_FILTER_PROMISCUOUS	0x01
76 #define KAWETH_PACKET_FILTER_ALL_MULTICAST	0x02
77 #define KAWETH_PACKET_FILTER_DIRECTED		0x04
78 #define KAWETH_PACKET_FILTER_BROADCAST		0x08
79 #define KAWETH_PACKET_FILTER_MULTICAST		0x10
80 
81 /* Table 7 */
82 #define KAWETH_COMMAND_GET_ETHERNET_DESC	0x00
83 #define KAWETH_COMMAND_MULTICAST_FILTERS        0x01
84 #define KAWETH_COMMAND_SET_PACKET_FILTER	0x02
85 #define KAWETH_COMMAND_STATISTICS               0x03
86 #define KAWETH_COMMAND_SET_TEMP_MAC     	0x06
87 #define KAWETH_COMMAND_GET_TEMP_MAC             0x07
88 #define KAWETH_COMMAND_SET_URB_SIZE		0x08
89 #define KAWETH_COMMAND_SET_SOFS_WAIT		0x09
90 #define KAWETH_COMMAND_SCAN			0xFF
91 
92 #define KAWETH_SOFS_TO_WAIT			0x05
93 
94 #define INTBUFFERSIZE				4
95 
96 #define STATE_OFFSET				0
97 #define STATE_MASK				0x40
98 #define	STATE_SHIFT				5
99 
100 #define IS_BLOCKED(s) (s & KAWETH_STATUS_BLOCKED)
101 
102 
103 MODULE_AUTHOR("Michael Zappe <zapman@interlan.net>, Stephane Alnet <stephane@u-picardie.fr>, Brad Hards <bhards@bigpond.net.au> and Oliver Neukum <oliver@neukum.org>");
104 MODULE_DESCRIPTION("KL5USB101 USB Ethernet driver");
105 MODULE_LICENSE("GPL");
106 MODULE_FIRMWARE("kaweth/new_code.bin");
107 MODULE_FIRMWARE("kaweth/new_code_fix.bin");
108 MODULE_FIRMWARE("kaweth/trigger_code.bin");
109 MODULE_FIRMWARE("kaweth/trigger_code_fix.bin");
110 
111 static const char driver_name[] = "kaweth";
112 
113 static int kaweth_probe(
114 		struct usb_interface *intf,
115 		const struct usb_device_id *id	/* from id_table */
116 	);
117 static void kaweth_disconnect(struct usb_interface *intf);
118 static int kaweth_internal_control_msg(struct usb_device *usb_dev,
119 				       unsigned int pipe,
120 				       struct usb_ctrlrequest *cmd, void *data,
121 				       int len, int timeout);
122 static int kaweth_suspend(struct usb_interface *intf, pm_message_t message);
123 static int kaweth_resume(struct usb_interface *intf);
124 
125 /****************************************************************
126  *     usb_device_id
127  ****************************************************************/
128 static struct usb_device_id usb_klsi_table[] = {
129 	{ USB_DEVICE(0x03e8, 0x0008) }, /* AOX Endpoints USB Ethernet */
130 	{ USB_DEVICE(0x04bb, 0x0901) }, /* I-O DATA USB-ET/T */
131 	{ USB_DEVICE(0x0506, 0x03e8) }, /* 3Com 3C19250 */
132 	{ USB_DEVICE(0x0506, 0x11f8) }, /* 3Com 3C460 */
133 	{ USB_DEVICE(0x0557, 0x2002) }, /* ATEN USB Ethernet */
134 	{ USB_DEVICE(0x0557, 0x4000) }, /* D-Link DSB-650C */
135 	{ USB_DEVICE(0x0565, 0x0002) }, /* Peracom Enet */
136 	{ USB_DEVICE(0x0565, 0x0003) }, /* Optus@Home UEP1045A */
137 	{ USB_DEVICE(0x0565, 0x0005) }, /* Peracom Enet2 */
138 	{ USB_DEVICE(0x05e9, 0x0008) }, /* KLSI KL5KUSB101B */
139 	{ USB_DEVICE(0x05e9, 0x0009) }, /* KLSI KL5KUSB101B (Board change) */
140 	{ USB_DEVICE(0x066b, 0x2202) }, /* Linksys USB10T */
141 	{ USB_DEVICE(0x06e1, 0x0008) }, /* ADS USB-10BT */
142 	{ USB_DEVICE(0x06e1, 0x0009) }, /* ADS USB-10BT */
143 	{ USB_DEVICE(0x0707, 0x0100) }, /* SMC 2202USB */
144 	{ USB_DEVICE(0x07aa, 0x0001) }, /* Correga K.K. */
145 	{ USB_DEVICE(0x07b8, 0x4000) }, /* D-Link DU-E10 */
146 	{ USB_DEVICE(0x07c9, 0xb010) }, /* Allied Telesyn AT-USB10 USB Ethernet Adapter */
147 	{ USB_DEVICE(0x0846, 0x1001) }, /* NetGear EA-101 */
148 	{ USB_DEVICE(0x0846, 0x1002) }, /* NetGear EA-101 */
149 	{ USB_DEVICE(0x085a, 0x0008) }, /* PortGear Ethernet Adapter */
150 	{ USB_DEVICE(0x085a, 0x0009) }, /* PortGear Ethernet Adapter */
151 	{ USB_DEVICE(0x087d, 0x5704) }, /* Jaton USB Ethernet Device Adapter */
152 	{ USB_DEVICE(0x0951, 0x0008) }, /* Kingston Technology USB Ethernet Adapter */
153 	{ USB_DEVICE(0x095a, 0x3003) }, /* Portsmith Express Ethernet Adapter */
154 	{ USB_DEVICE(0x10bd, 0x1427) }, /* ASANTE USB To Ethernet Adapter */
155 	{ USB_DEVICE(0x1342, 0x0204) }, /* Mobility USB-Ethernet Adapter */
156 	{ USB_DEVICE(0x13d2, 0x0400) }, /* Shark Pocket Adapter */
157 	{ USB_DEVICE(0x1485, 0x0001) },	/* Silicom U2E */
158 	{ USB_DEVICE(0x1485, 0x0002) }, /* Psion Dacom Gold Port Ethernet */
159 	{ USB_DEVICE(0x1645, 0x0005) }, /* Entrega E45 */
160 	{ USB_DEVICE(0x1645, 0x0008) }, /* Entrega USB Ethernet Adapter */
161 	{ USB_DEVICE(0x1645, 0x8005) }, /* PortGear Ethernet Adapter */
162 	{ USB_DEVICE(0x1668, 0x0323) }, /* Actiontec USB Ethernet */
163 	{ USB_DEVICE(0x2001, 0x4000) }, /* D-link DSB-650C */
164 	{} /* Null terminator */
165 };
166 
167 MODULE_DEVICE_TABLE (usb, usb_klsi_table);
168 
169 /****************************************************************
170  *     kaweth_driver
171  ****************************************************************/
172 static struct usb_driver kaweth_driver = {
173 	.name =		driver_name,
174 	.probe =	kaweth_probe,
175 	.disconnect =	kaweth_disconnect,
176 	.suspend =	kaweth_suspend,
177 	.resume =	kaweth_resume,
178 	.id_table =     usb_klsi_table,
179 	.supports_autosuspend =	1,
180 	.disable_hub_initiated_lpm = 1,
181 };
182 
183 typedef __u8 eth_addr_t[6];
184 
185 /****************************************************************
186  *     usb_eth_dev
187  ****************************************************************/
188 struct usb_eth_dev {
189 	char *name;
190 	__u16 vendor;
191 	__u16 device;
192 	void *pdata;
193 };
194 
195 /****************************************************************
196  *     kaweth_ethernet_configuration
197  *     Refer Table 8
198  ****************************************************************/
199 struct kaweth_ethernet_configuration
200 {
201 	__u8 size;
202 	__u8 reserved1;
203 	__u8 reserved2;
204 	eth_addr_t hw_addr;
205 	__u32 statistics_mask;
206 	__le16 segment_size;
207 	__u16 max_multicast_filters;
208 	__u8 reserved3;
209 } __packed;
210 
211 /****************************************************************
212  *     kaweth_device
213  ****************************************************************/
214 struct kaweth_device
215 {
216 	spinlock_t device_lock;
217 
218 	__u32 status;
219 	int end;
220 	int suspend_lowmem_rx;
221 	int suspend_lowmem_ctrl;
222 	int linkstate;
223 	int opened;
224 	struct delayed_work lowmem_work;
225 
226 	struct usb_device *dev;
227 	struct usb_interface *intf;
228 	struct net_device *net;
229 	wait_queue_head_t term_wait;
230 
231 	struct urb *rx_urb;
232 	struct urb *tx_urb;
233 	struct urb *irq_urb;
234 
235 	dma_addr_t intbufferhandle;
236 	__u8 *intbuffer;
237 	dma_addr_t rxbufferhandle;
238 	__u8 *rx_buf;
239 
240 
241 	struct sk_buff *tx_skb;
242 
243 	__u8 *firmware_buf;
244 	__u8 scratch[KAWETH_SCRATCH_SIZE];
245 	__u16 packet_filter_bitmap;
246 
247 	struct kaweth_ethernet_configuration configuration;
248 
249 	struct net_device_stats stats;
250 };
251 
252 /****************************************************************
253  *     kaweth_control
254  ****************************************************************/
255 static int kaweth_control(struct kaweth_device *kaweth,
256 			  unsigned int pipe,
257 			  __u8 request,
258 			  __u8 requesttype,
259 			  __u16 value,
260 			  __u16 index,
261 			  void *data,
262 			  __u16 size,
263 			  int timeout)
264 {
265 	struct usb_ctrlrequest *dr;
266 	int retval;
267 
268 	netdev_dbg(kaweth->net, "kaweth_control()\n");
269 
270 	if(in_interrupt()) {
271 		netdev_dbg(kaweth->net, "in_interrupt()\n");
272 		return -EBUSY;
273 	}
274 
275 	dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
276 	if (!dr)
277 		return -ENOMEM;
278 
279 	dr->bRequestType = requesttype;
280 	dr->bRequest = request;
281 	dr->wValue = cpu_to_le16(value);
282 	dr->wIndex = cpu_to_le16(index);
283 	dr->wLength = cpu_to_le16(size);
284 
285 	retval = kaweth_internal_control_msg(kaweth->dev,
286 					     pipe,
287 					     dr,
288 					     data,
289 					     size,
290 					     timeout);
291 
292 	kfree(dr);
293 	return retval;
294 }
295 
296 /****************************************************************
297  *     kaweth_read_configuration
298  ****************************************************************/
299 static int kaweth_read_configuration(struct kaweth_device *kaweth)
300 {
301 	int retval;
302 
303 	netdev_dbg(kaweth->net, "Reading kaweth configuration\n");
304 
305 	retval = kaweth_control(kaweth,
306 				usb_rcvctrlpipe(kaweth->dev, 0),
307 				KAWETH_COMMAND_GET_ETHERNET_DESC,
308 				USB_TYPE_VENDOR | USB_DIR_IN | USB_RECIP_DEVICE,
309 				0,
310 				0,
311 				(void *)&kaweth->configuration,
312 				sizeof(kaweth->configuration),
313 				KAWETH_CONTROL_TIMEOUT);
314 
315 	return retval;
316 }
317 
318 /****************************************************************
319  *     kaweth_set_urb_size
320  ****************************************************************/
321 static int kaweth_set_urb_size(struct kaweth_device *kaweth, __u16 urb_size)
322 {
323 	int retval;
324 
325 	netdev_dbg(kaweth->net, "Setting URB size to %d\n", (unsigned)urb_size);
326 
327 	retval = kaweth_control(kaweth,
328 				usb_sndctrlpipe(kaweth->dev, 0),
329 				KAWETH_COMMAND_SET_URB_SIZE,
330 				USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE,
331 				urb_size,
332 				0,
333 				(void *)&kaweth->scratch,
334 				0,
335 				KAWETH_CONTROL_TIMEOUT);
336 
337 	return retval;
338 }
339 
340 /****************************************************************
341  *     kaweth_set_sofs_wait
342  ****************************************************************/
343 static int kaweth_set_sofs_wait(struct kaweth_device *kaweth, __u16 sofs_wait)
344 {
345 	int retval;
346 
347 	netdev_dbg(kaweth->net, "Set SOFS wait to %d\n", (unsigned)sofs_wait);
348 
349 	retval = kaweth_control(kaweth,
350 				usb_sndctrlpipe(kaweth->dev, 0),
351 				KAWETH_COMMAND_SET_SOFS_WAIT,
352 				USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE,
353 				sofs_wait,
354 				0,
355 				(void *)&kaweth->scratch,
356 				0,
357 				KAWETH_CONTROL_TIMEOUT);
358 
359 	return retval;
360 }
361 
362 /****************************************************************
363  *     kaweth_set_receive_filter
364  ****************************************************************/
365 static int kaweth_set_receive_filter(struct kaweth_device *kaweth,
366 				     __u16 receive_filter)
367 {
368 	int retval;
369 
370 	netdev_dbg(kaweth->net, "Set receive filter to %d\n",
371 		   (unsigned)receive_filter);
372 
373 	retval = kaweth_control(kaweth,
374 				usb_sndctrlpipe(kaweth->dev, 0),
375 				KAWETH_COMMAND_SET_PACKET_FILTER,
376 				USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE,
377 				receive_filter,
378 				0,
379 				(void *)&kaweth->scratch,
380 				0,
381 				KAWETH_CONTROL_TIMEOUT);
382 
383 	return retval;
384 }
385 
386 /****************************************************************
387  *     kaweth_download_firmware
388  ****************************************************************/
389 static int kaweth_download_firmware(struct kaweth_device *kaweth,
390 				    const char *fwname,
391 				    __u8 interrupt,
392 				    __u8 type)
393 {
394 	const struct firmware *fw;
395 	int data_len;
396 	int ret;
397 
398 	ret = request_firmware(&fw, fwname, &kaweth->dev->dev);
399 	if (ret) {
400 		dev_err(&kaweth->intf->dev, "Firmware request failed\n");
401 		return ret;
402 	}
403 
404 	if (fw->size > KAWETH_FIRMWARE_BUF_SIZE) {
405 		dev_err(&kaweth->intf->dev, "Firmware too big: %zu\n",
406 			fw->size);
407 		release_firmware(fw);
408 		return -ENOSPC;
409 	}
410 	data_len = fw->size;
411 	memcpy(kaweth->firmware_buf, fw->data, fw->size);
412 
413 	release_firmware(fw);
414 
415 	kaweth->firmware_buf[2] = (data_len & 0xFF) - 7;
416 	kaweth->firmware_buf[3] = data_len >> 8;
417 	kaweth->firmware_buf[4] = type;
418 	kaweth->firmware_buf[5] = interrupt;
419 
420 	netdev_dbg(kaweth->net, "High: %i, Low:%i\n", kaweth->firmware_buf[3],
421 		   kaweth->firmware_buf[2]);
422 
423 	netdev_dbg(kaweth->net,
424 		   "Downloading firmware at %p to kaweth device at %p\n",
425 		   kaweth->firmware_buf, kaweth);
426 	netdev_dbg(kaweth->net, "Firmware length: %d\n", data_len);
427 
428 	return kaweth_control(kaweth,
429 		              usb_sndctrlpipe(kaweth->dev, 0),
430 			      KAWETH_COMMAND_SCAN,
431 			      USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE,
432 			      0,
433 			      0,
434 			      (void *)kaweth->firmware_buf,
435 			      data_len,
436 			      KAWETH_CONTROL_TIMEOUT);
437 }
438 
439 /****************************************************************
440  *     kaweth_trigger_firmware
441  ****************************************************************/
442 static int kaweth_trigger_firmware(struct kaweth_device *kaweth,
443 				   __u8 interrupt)
444 {
445 	kaweth->firmware_buf[0] = 0xB6;
446 	kaweth->firmware_buf[1] = 0xC3;
447 	kaweth->firmware_buf[2] = 0x01;
448 	kaweth->firmware_buf[3] = 0x00;
449 	kaweth->firmware_buf[4] = 0x06;
450 	kaweth->firmware_buf[5] = interrupt;
451 	kaweth->firmware_buf[6] = 0x00;
452 	kaweth->firmware_buf[7] = 0x00;
453 
454 	netdev_dbg(kaweth->net, "Triggering firmware\n");
455 
456 	return kaweth_control(kaweth,
457 			      usb_sndctrlpipe(kaweth->dev, 0),
458 			      KAWETH_COMMAND_SCAN,
459 			      USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE,
460 			      0,
461 			      0,
462 			      (void *)kaweth->firmware_buf,
463 			      8,
464 			      KAWETH_CONTROL_TIMEOUT);
465 }
466 
467 /****************************************************************
468  *     kaweth_reset
469  ****************************************************************/
470 static int kaweth_reset(struct kaweth_device *kaweth)
471 {
472 	int result;
473 
474 	netdev_dbg(kaweth->net, "kaweth_reset(%p)\n", kaweth);
475 	result = usb_reset_configuration(kaweth->dev);
476 	mdelay(10);
477 
478 	netdev_dbg(kaweth->net, "kaweth_reset() returns %d.\n", result);
479 
480 	return result;
481 }
482 
483 static void kaweth_usb_receive(struct urb *);
484 static int kaweth_resubmit_rx_urb(struct kaweth_device *, gfp_t);
485 
486 /****************************************************************
487 	int_callback
488 *****************************************************************/
489 
490 static void kaweth_resubmit_int_urb(struct kaweth_device *kaweth, gfp_t mf)
491 {
492 	int status;
493 
494 	status = usb_submit_urb (kaweth->irq_urb, mf);
495 	if (unlikely(status == -ENOMEM)) {
496 		kaweth->suspend_lowmem_ctrl = 1;
497 		schedule_delayed_work(&kaweth->lowmem_work, HZ/4);
498 	} else {
499 		kaweth->suspend_lowmem_ctrl = 0;
500 	}
501 
502 	if (status)
503 		dev_err(&kaweth->intf->dev,
504 			"can't resubmit intr, %s-%s, status %d\n",
505 			kaweth->dev->bus->bus_name,
506 			kaweth->dev->devpath, status);
507 }
508 
509 static void int_callback(struct urb *u)
510 {
511 	struct kaweth_device *kaweth = u->context;
512 	int act_state;
513 	int status = u->status;
514 
515 	switch (status) {
516 	case 0:			/* success */
517 		break;
518 	case -ECONNRESET:	/* unlink */
519 	case -ENOENT:
520 	case -ESHUTDOWN:
521 		return;
522 	/* -EPIPE:  should clear the halt */
523 	default:		/* error */
524 		goto resubmit;
525 	}
526 
527 	/* we check the link state to report changes */
528 	if (kaweth->linkstate != (act_state = ( kaweth->intbuffer[STATE_OFFSET] | STATE_MASK) >> STATE_SHIFT)) {
529 		if (act_state)
530 			netif_carrier_on(kaweth->net);
531 		else
532 			netif_carrier_off(kaweth->net);
533 
534 		kaweth->linkstate = act_state;
535 	}
536 resubmit:
537 	kaweth_resubmit_int_urb(kaweth, GFP_ATOMIC);
538 }
539 
540 static void kaweth_resubmit_tl(struct work_struct *work)
541 {
542 	struct kaweth_device *kaweth =
543 		container_of(work, struct kaweth_device, lowmem_work.work);
544 
545 	if (IS_BLOCKED(kaweth->status))
546 		return;
547 
548 	if (kaweth->suspend_lowmem_rx)
549 		kaweth_resubmit_rx_urb(kaweth, GFP_NOIO);
550 
551 	if (kaweth->suspend_lowmem_ctrl)
552 		kaweth_resubmit_int_urb(kaweth, GFP_NOIO);
553 }
554 
555 
556 /****************************************************************
557  *     kaweth_resubmit_rx_urb
558  ****************************************************************/
559 static int kaweth_resubmit_rx_urb(struct kaweth_device *kaweth,
560 						gfp_t mem_flags)
561 {
562 	int result;
563 
564 	usb_fill_bulk_urb(kaweth->rx_urb,
565 		      kaweth->dev,
566 		      usb_rcvbulkpipe(kaweth->dev, 1),
567 		      kaweth->rx_buf,
568 		      KAWETH_BUF_SIZE,
569 		      kaweth_usb_receive,
570 		      kaweth);
571 	kaweth->rx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
572 	kaweth->rx_urb->transfer_dma = kaweth->rxbufferhandle;
573 
574 	if((result = usb_submit_urb(kaweth->rx_urb, mem_flags))) {
575 		if (result == -ENOMEM) {
576 			kaweth->suspend_lowmem_rx = 1;
577 			schedule_delayed_work(&kaweth->lowmem_work, HZ/4);
578 		}
579 		dev_err(&kaweth->intf->dev, "resubmitting rx_urb %d failed\n",
580 			result);
581 	} else {
582 		kaweth->suspend_lowmem_rx = 0;
583 	}
584 
585 	return result;
586 }
587 
588 static void kaweth_async_set_rx_mode(struct kaweth_device *kaweth);
589 
590 /****************************************************************
591  *     kaweth_usb_receive
592  ****************************************************************/
593 static void kaweth_usb_receive(struct urb *urb)
594 {
595 	struct device *dev = &urb->dev->dev;
596 	struct kaweth_device *kaweth = urb->context;
597 	struct net_device *net = kaweth->net;
598 	int status = urb->status;
599 
600 	int count = urb->actual_length;
601 	int count2 = urb->transfer_buffer_length;
602 
603 	__u16 pkt_len = le16_to_cpup((__le16 *)kaweth->rx_buf);
604 
605 	struct sk_buff *skb;
606 
607 	if (unlikely(status == -EPIPE)) {
608 		kaweth->stats.rx_errors++;
609 		kaweth->end = 1;
610 		wake_up(&kaweth->term_wait);
611 		dev_dbg(dev, "Status was -EPIPE.\n");
612 		return;
613 	}
614 	if (unlikely(status == -ECONNRESET || status == -ESHUTDOWN)) {
615 		/* we are killed - set a flag and wake the disconnect handler */
616 		kaweth->end = 1;
617 		wake_up(&kaweth->term_wait);
618 		dev_dbg(dev, "Status was -ECONNRESET or -ESHUTDOWN.\n");
619 		return;
620 	}
621 	if (unlikely(status == -EPROTO || status == -ETIME ||
622 		     status == -EILSEQ)) {
623 		kaweth->stats.rx_errors++;
624 		dev_dbg(dev, "Status was -EPROTO, -ETIME, or -EILSEQ.\n");
625 		return;
626 	}
627 	if (unlikely(status == -EOVERFLOW)) {
628 		kaweth->stats.rx_errors++;
629 		dev_dbg(dev, "Status was -EOVERFLOW.\n");
630 	}
631 	spin_lock(&kaweth->device_lock);
632 	if (IS_BLOCKED(kaweth->status)) {
633 		spin_unlock(&kaweth->device_lock);
634 		return;
635 	}
636 	spin_unlock(&kaweth->device_lock);
637 
638 	if(status && status != -EREMOTEIO && count != 1) {
639 		dev_err(&kaweth->intf->dev,
640 			"%s RX status: %d count: %d packet_len: %d\n",
641 			net->name, status, count, (int)pkt_len);
642 		kaweth_resubmit_rx_urb(kaweth, GFP_ATOMIC);
643                 return;
644 	}
645 
646 	if(kaweth->net && (count > 2)) {
647 		if(pkt_len > (count - 2)) {
648 			dev_err(&kaweth->intf->dev,
649 				"Packet length too long for USB frame (pkt_len: %x, count: %x)\n",
650 				pkt_len, count);
651 			dev_err(&kaweth->intf->dev, "Packet len & 2047: %x\n",
652 				pkt_len & 2047);
653 			dev_err(&kaweth->intf->dev, "Count 2: %x\n", count2);
654 		        kaweth_resubmit_rx_urb(kaweth, GFP_ATOMIC);
655                         return;
656                 }
657 
658 		if(!(skb = dev_alloc_skb(pkt_len+2))) {
659 		        kaweth_resubmit_rx_urb(kaweth, GFP_ATOMIC);
660                         return;
661 		}
662 
663 		skb_reserve(skb, 2);    /* Align IP on 16 byte boundaries */
664 
665 		skb_copy_to_linear_data(skb, kaweth->rx_buf + 2, pkt_len);
666 
667 		skb_put(skb, pkt_len);
668 
669 		skb->protocol = eth_type_trans(skb, net);
670 
671 		netif_rx(skb);
672 
673 		kaweth->stats.rx_packets++;
674 		kaweth->stats.rx_bytes += pkt_len;
675 	}
676 
677 	kaweth_resubmit_rx_urb(kaweth, GFP_ATOMIC);
678 }
679 
680 /****************************************************************
681  *     kaweth_open
682  ****************************************************************/
683 static int kaweth_open(struct net_device *net)
684 {
685 	struct kaweth_device *kaweth = netdev_priv(net);
686 	int res;
687 
688 	netdev_dbg(kaweth->net, "Opening network device.\n");
689 
690 	res = usb_autopm_get_interface(kaweth->intf);
691 	if (res) {
692 		dev_err(&kaweth->intf->dev, "Interface cannot be resumed.\n");
693 		return -EIO;
694 	}
695 	res = kaweth_resubmit_rx_urb(kaweth, GFP_KERNEL);
696 	if (res)
697 		goto err_out;
698 
699 	usb_fill_int_urb(
700 		kaweth->irq_urb,
701 		kaweth->dev,
702 		usb_rcvintpipe(kaweth->dev, 3),
703 		kaweth->intbuffer,
704 		INTBUFFERSIZE,
705 		int_callback,
706 		kaweth,
707 		250); /* overriding the descriptor */
708 	kaweth->irq_urb->transfer_dma = kaweth->intbufferhandle;
709 	kaweth->irq_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
710 
711 	res = usb_submit_urb(kaweth->irq_urb, GFP_KERNEL);
712 	if (res) {
713 		usb_kill_urb(kaweth->rx_urb);
714 		goto err_out;
715 	}
716 	kaweth->opened = 1;
717 
718 	netif_start_queue(net);
719 
720 	kaweth_async_set_rx_mode(kaweth);
721 	return 0;
722 
723 err_out:
724 	usb_autopm_put_interface(kaweth->intf);
725 	return -EIO;
726 }
727 
728 /****************************************************************
729  *     kaweth_kill_urbs
730  ****************************************************************/
731 static void kaweth_kill_urbs(struct kaweth_device *kaweth)
732 {
733 	usb_kill_urb(kaweth->irq_urb);
734 	usb_kill_urb(kaweth->rx_urb);
735 	usb_kill_urb(kaweth->tx_urb);
736 
737 	cancel_delayed_work_sync(&kaweth->lowmem_work);
738 
739 	/* a scheduled work may have resubmitted,
740 	   we hit them again */
741 	usb_kill_urb(kaweth->irq_urb);
742 	usb_kill_urb(kaweth->rx_urb);
743 }
744 
745 /****************************************************************
746  *     kaweth_close
747  ****************************************************************/
748 static int kaweth_close(struct net_device *net)
749 {
750 	struct kaweth_device *kaweth = netdev_priv(net);
751 
752 	netif_stop_queue(net);
753 	kaweth->opened = 0;
754 
755 	kaweth->status |= KAWETH_STATUS_CLOSING;
756 
757 	kaweth_kill_urbs(kaweth);
758 
759 	kaweth->status &= ~KAWETH_STATUS_CLOSING;
760 
761 	usb_autopm_put_interface(kaweth->intf);
762 
763 	return 0;
764 }
765 
766 static u32 kaweth_get_link(struct net_device *dev)
767 {
768 	struct kaweth_device *kaweth = netdev_priv(dev);
769 
770 	return kaweth->linkstate;
771 }
772 
773 static const struct ethtool_ops ops = {
774 	.get_link	= kaweth_get_link
775 };
776 
777 /****************************************************************
778  *     kaweth_usb_transmit_complete
779  ****************************************************************/
780 static void kaweth_usb_transmit_complete(struct urb *urb)
781 {
782 	struct kaweth_device *kaweth = urb->context;
783 	struct sk_buff *skb = kaweth->tx_skb;
784 	int status = urb->status;
785 
786 	if (unlikely(status != 0))
787 		if (status != -ENOENT)
788 			dev_dbg(&urb->dev->dev, "%s: TX status %d.\n",
789 				kaweth->net->name, status);
790 
791 	netif_wake_queue(kaweth->net);
792 	dev_kfree_skb_irq(skb);
793 }
794 
795 /****************************************************************
796  *     kaweth_start_xmit
797  ****************************************************************/
798 static netdev_tx_t kaweth_start_xmit(struct sk_buff *skb,
799 					   struct net_device *net)
800 {
801 	struct kaweth_device *kaweth = netdev_priv(net);
802 	__le16 *private_header;
803 
804 	int res;
805 
806 	spin_lock_irq(&kaweth->device_lock);
807 
808 	kaweth_async_set_rx_mode(kaweth);
809 	netif_stop_queue(net);
810 	if (IS_BLOCKED(kaweth->status)) {
811 		goto skip;
812 	}
813 
814 	/* We now decide whether we can put our special header into the sk_buff */
815 	if (skb_cloned(skb) || skb_headroom(skb) < 2) {
816 		/* no such luck - we make our own */
817 		struct sk_buff *copied_skb;
818 		copied_skb = skb_copy_expand(skb, 2, 0, GFP_ATOMIC);
819 		dev_kfree_skb_irq(skb);
820 		skb = copied_skb;
821 		if (!copied_skb) {
822 			kaweth->stats.tx_errors++;
823 			netif_start_queue(net);
824 			spin_unlock_irq(&kaweth->device_lock);
825 			return NETDEV_TX_OK;
826 		}
827 	}
828 
829 	private_header = (__le16 *)__skb_push(skb, 2);
830 	*private_header = cpu_to_le16(skb->len-2);
831 	kaweth->tx_skb = skb;
832 
833 	usb_fill_bulk_urb(kaweth->tx_urb,
834 		      kaweth->dev,
835 		      usb_sndbulkpipe(kaweth->dev, 2),
836 		      private_header,
837 		      skb->len,
838 		      kaweth_usb_transmit_complete,
839 		      kaweth);
840 	kaweth->end = 0;
841 
842 	if((res = usb_submit_urb(kaweth->tx_urb, GFP_ATOMIC)))
843 	{
844 		dev_warn(&net->dev, "kaweth failed tx_urb %d\n", res);
845 skip:
846 		kaweth->stats.tx_errors++;
847 
848 		netif_start_queue(net);
849 		dev_kfree_skb_irq(skb);
850 	}
851 	else
852 	{
853 		kaweth->stats.tx_packets++;
854 		kaweth->stats.tx_bytes += skb->len;
855 	}
856 
857 	spin_unlock_irq(&kaweth->device_lock);
858 
859 	return NETDEV_TX_OK;
860 }
861 
862 /****************************************************************
863  *     kaweth_set_rx_mode
864  ****************************************************************/
865 static void kaweth_set_rx_mode(struct net_device *net)
866 {
867 	struct kaweth_device *kaweth = netdev_priv(net);
868 
869 	__u16 packet_filter_bitmap = KAWETH_PACKET_FILTER_DIRECTED |
870                                      KAWETH_PACKET_FILTER_BROADCAST |
871 		                     KAWETH_PACKET_FILTER_MULTICAST;
872 
873 	netdev_dbg(net, "Setting Rx mode to %d\n", packet_filter_bitmap);
874 
875 	netif_stop_queue(net);
876 
877 	if (net->flags & IFF_PROMISC) {
878 		packet_filter_bitmap |= KAWETH_PACKET_FILTER_PROMISCUOUS;
879 	}
880 	else if (!netdev_mc_empty(net) || (net->flags & IFF_ALLMULTI)) {
881 		packet_filter_bitmap |= KAWETH_PACKET_FILTER_ALL_MULTICAST;
882 	}
883 
884 	kaweth->packet_filter_bitmap = packet_filter_bitmap;
885 	netif_wake_queue(net);
886 }
887 
888 /****************************************************************
889  *     kaweth_async_set_rx_mode
890  ****************************************************************/
891 static void kaweth_async_set_rx_mode(struct kaweth_device *kaweth)
892 {
893 	int result;
894 	__u16 packet_filter_bitmap = kaweth->packet_filter_bitmap;
895 
896 	kaweth->packet_filter_bitmap = 0;
897 	if (packet_filter_bitmap == 0)
898 		return;
899 
900 	if (in_interrupt())
901 		return;
902 
903 	result = kaweth_control(kaweth,
904 				usb_sndctrlpipe(kaweth->dev, 0),
905 				KAWETH_COMMAND_SET_PACKET_FILTER,
906 				USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE,
907 				packet_filter_bitmap,
908 				0,
909 				(void *)&kaweth->scratch,
910 				0,
911 				KAWETH_CONTROL_TIMEOUT);
912 
913 	if(result < 0) {
914 		dev_err(&kaweth->intf->dev, "Failed to set Rx mode: %d\n",
915 			result);
916 	}
917 	else {
918 		netdev_dbg(kaweth->net, "Set Rx mode to %d\n",
919 			   packet_filter_bitmap);
920 	}
921 }
922 
923 /****************************************************************
924  *     kaweth_netdev_stats
925  ****************************************************************/
926 static struct net_device_stats *kaweth_netdev_stats(struct net_device *dev)
927 {
928 	struct kaweth_device *kaweth = netdev_priv(dev);
929 	return &kaweth->stats;
930 }
931 
932 /****************************************************************
933  *     kaweth_tx_timeout
934  ****************************************************************/
935 static void kaweth_tx_timeout(struct net_device *net)
936 {
937 	struct kaweth_device *kaweth = netdev_priv(net);
938 
939 	dev_warn(&net->dev, "%s: Tx timed out. Resetting.\n", net->name);
940 	kaweth->stats.tx_errors++;
941 	net->trans_start = jiffies;
942 
943 	usb_unlink_urb(kaweth->tx_urb);
944 }
945 
946 /****************************************************************
947  *     kaweth_suspend
948  ****************************************************************/
949 static int kaweth_suspend(struct usb_interface *intf, pm_message_t message)
950 {
951 	struct kaweth_device *kaweth = usb_get_intfdata(intf);
952 	unsigned long flags;
953 
954 	dev_dbg(&intf->dev, "Suspending device\n");
955 	spin_lock_irqsave(&kaweth->device_lock, flags);
956 	kaweth->status |= KAWETH_STATUS_SUSPENDING;
957 	spin_unlock_irqrestore(&kaweth->device_lock, flags);
958 
959 	kaweth_kill_urbs(kaweth);
960 	return 0;
961 }
962 
963 /****************************************************************
964  *     kaweth_resume
965  ****************************************************************/
966 static int kaweth_resume(struct usb_interface *intf)
967 {
968 	struct kaweth_device *kaweth = usb_get_intfdata(intf);
969 	unsigned long flags;
970 
971 	dev_dbg(&intf->dev, "Resuming device\n");
972 	spin_lock_irqsave(&kaweth->device_lock, flags);
973 	kaweth->status &= ~KAWETH_STATUS_SUSPENDING;
974 	spin_unlock_irqrestore(&kaweth->device_lock, flags);
975 
976 	if (!kaweth->opened)
977 		return 0;
978 	kaweth_resubmit_rx_urb(kaweth, GFP_NOIO);
979 	kaweth_resubmit_int_urb(kaweth, GFP_NOIO);
980 
981 	return 0;
982 }
983 
984 /****************************************************************
985  *     kaweth_probe
986  ****************************************************************/
987 
988 
989 static const struct net_device_ops kaweth_netdev_ops = {
990 	.ndo_open =			kaweth_open,
991 	.ndo_stop =			kaweth_close,
992 	.ndo_start_xmit =		kaweth_start_xmit,
993 	.ndo_tx_timeout =		kaweth_tx_timeout,
994 	.ndo_set_rx_mode =		kaweth_set_rx_mode,
995 	.ndo_get_stats =		kaweth_netdev_stats,
996 	.ndo_change_mtu =		eth_change_mtu,
997 	.ndo_set_mac_address =		eth_mac_addr,
998 	.ndo_validate_addr =		eth_validate_addr,
999 };
1000 
1001 static int kaweth_probe(
1002 		struct usb_interface *intf,
1003 		const struct usb_device_id *id      /* from id_table */
1004 	)
1005 {
1006 	struct device *dev = &intf->dev;
1007 	struct usb_device *udev = interface_to_usbdev(intf);
1008 	struct kaweth_device *kaweth;
1009 	struct net_device *netdev;
1010 	const eth_addr_t bcast_addr = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
1011 	int result = 0;
1012 
1013 	dev_dbg(dev,
1014 		"Kawasaki Device Probe (Device number:%d): 0x%4.4x:0x%4.4x:0x%4.4x\n",
1015 		udev->devnum, le16_to_cpu(udev->descriptor.idVendor),
1016 		le16_to_cpu(udev->descriptor.idProduct),
1017 		le16_to_cpu(udev->descriptor.bcdDevice));
1018 
1019 	dev_dbg(dev, "Device at %p\n", udev);
1020 
1021 	dev_dbg(dev, "Descriptor length: %x type: %x\n",
1022 		(int)udev->descriptor.bLength,
1023 		(int)udev->descriptor.bDescriptorType);
1024 
1025 	netdev = alloc_etherdev(sizeof(*kaweth));
1026 	if (!netdev)
1027 		return -ENOMEM;
1028 
1029 	kaweth = netdev_priv(netdev);
1030 	kaweth->dev = udev;
1031 	kaweth->net = netdev;
1032 
1033 	spin_lock_init(&kaweth->device_lock);
1034 	init_waitqueue_head(&kaweth->term_wait);
1035 
1036 	dev_dbg(dev, "Resetting.\n");
1037 
1038 	kaweth_reset(kaweth);
1039 
1040 	/*
1041 	 * If high byte of bcdDevice is nonzero, firmware is already
1042 	 * downloaded. Don't try to do it again, or we'll hang the device.
1043 	 */
1044 
1045 	if (le16_to_cpu(udev->descriptor.bcdDevice) >> 8) {
1046 		dev_info(dev, "Firmware present in device.\n");
1047 	} else {
1048 		/* Download the firmware */
1049 		dev_info(dev, "Downloading firmware...\n");
1050 		kaweth->firmware_buf = (__u8 *)__get_free_page(GFP_KERNEL);
1051 		if ((result = kaweth_download_firmware(kaweth,
1052 						      "kaweth/new_code.bin",
1053 						      100,
1054 						      2)) < 0) {
1055 			dev_err(dev, "Error downloading firmware (%d)\n",
1056 				result);
1057 			goto err_fw;
1058 		}
1059 
1060 		if ((result = kaweth_download_firmware(kaweth,
1061 						      "kaweth/new_code_fix.bin",
1062 						      100,
1063 						      3)) < 0) {
1064 			dev_err(dev, "Error downloading firmware fix (%d)\n",
1065 				result);
1066 			goto err_fw;
1067 		}
1068 
1069 		if ((result = kaweth_download_firmware(kaweth,
1070 						      "kaweth/trigger_code.bin",
1071 						      126,
1072 						      2)) < 0) {
1073 			dev_err(dev, "Error downloading trigger code (%d)\n",
1074 				result);
1075 			goto err_fw;
1076 
1077 		}
1078 
1079 		if ((result = kaweth_download_firmware(kaweth,
1080 						      "kaweth/trigger_code_fix.bin",
1081 						      126,
1082 						      3)) < 0) {
1083 			dev_err(dev, "Error downloading trigger code fix (%d)\n", result);
1084 			goto err_fw;
1085 		}
1086 
1087 
1088 		if ((result = kaweth_trigger_firmware(kaweth, 126)) < 0) {
1089 			dev_err(dev, "Error triggering firmware (%d)\n", result);
1090 			goto err_fw;
1091 		}
1092 
1093 		/* Device will now disappear for a moment...  */
1094 		dev_info(dev, "Firmware loaded.  I'll be back...\n");
1095 err_fw:
1096 		free_page((unsigned long)kaweth->firmware_buf);
1097 		free_netdev(netdev);
1098 		return -EIO;
1099 	}
1100 
1101 	result = kaweth_read_configuration(kaweth);
1102 
1103 	if(result < 0) {
1104 		dev_err(dev, "Error reading configuration (%d), no net device created\n", result);
1105 		goto err_free_netdev;
1106 	}
1107 
1108 	dev_info(dev, "Statistics collection: %x\n", kaweth->configuration.statistics_mask);
1109 	dev_info(dev, "Multicast filter limit: %x\n", kaweth->configuration.max_multicast_filters & ((1 << 15) - 1));
1110 	dev_info(dev, "MTU: %d\n", le16_to_cpu(kaweth->configuration.segment_size));
1111 	dev_info(dev, "Read MAC address %pM\n", kaweth->configuration.hw_addr);
1112 
1113 	if(!memcmp(&kaweth->configuration.hw_addr,
1114                    &bcast_addr,
1115 		   sizeof(bcast_addr))) {
1116 		dev_err(dev, "Firmware not functioning properly, no net device created\n");
1117 		goto err_free_netdev;
1118 	}
1119 
1120 	if(kaweth_set_urb_size(kaweth, KAWETH_BUF_SIZE) < 0) {
1121 		dev_dbg(dev, "Error setting URB size\n");
1122 		goto err_free_netdev;
1123 	}
1124 
1125 	if(kaweth_set_sofs_wait(kaweth, KAWETH_SOFS_TO_WAIT) < 0) {
1126 		dev_err(dev, "Error setting SOFS wait\n");
1127 		goto err_free_netdev;
1128 	}
1129 
1130 	result = kaweth_set_receive_filter(kaweth,
1131                                            KAWETH_PACKET_FILTER_DIRECTED |
1132                                            KAWETH_PACKET_FILTER_BROADCAST |
1133                                            KAWETH_PACKET_FILTER_MULTICAST);
1134 
1135 	if(result < 0) {
1136 		dev_err(dev, "Error setting receive filter\n");
1137 		goto err_free_netdev;
1138 	}
1139 
1140 	dev_dbg(dev, "Initializing net device.\n");
1141 
1142 	kaweth->intf = intf;
1143 
1144 	kaweth->tx_urb = usb_alloc_urb(0, GFP_KERNEL);
1145 	if (!kaweth->tx_urb)
1146 		goto err_free_netdev;
1147 	kaweth->rx_urb = usb_alloc_urb(0, GFP_KERNEL);
1148 	if (!kaweth->rx_urb)
1149 		goto err_only_tx;
1150 	kaweth->irq_urb = usb_alloc_urb(0, GFP_KERNEL);
1151 	if (!kaweth->irq_urb)
1152 		goto err_tx_and_rx;
1153 
1154 	kaweth->intbuffer = usb_alloc_coherent(	kaweth->dev,
1155 						INTBUFFERSIZE,
1156 						GFP_KERNEL,
1157 						&kaweth->intbufferhandle);
1158 	if (!kaweth->intbuffer)
1159 		goto err_tx_and_rx_and_irq;
1160 	kaweth->rx_buf = usb_alloc_coherent(	kaweth->dev,
1161 						KAWETH_BUF_SIZE,
1162 						GFP_KERNEL,
1163 						&kaweth->rxbufferhandle);
1164 	if (!kaweth->rx_buf)
1165 		goto err_all_but_rxbuf;
1166 
1167 	memcpy(netdev->broadcast, &bcast_addr, sizeof(bcast_addr));
1168 	memcpy(netdev->dev_addr, &kaweth->configuration.hw_addr,
1169                sizeof(kaweth->configuration.hw_addr));
1170 
1171 	netdev->netdev_ops = &kaweth_netdev_ops;
1172 	netdev->watchdog_timeo = KAWETH_TX_TIMEOUT;
1173 	netdev->mtu = le16_to_cpu(kaweth->configuration.segment_size);
1174 	netdev->ethtool_ops = &ops;
1175 
1176 	/* kaweth is zeroed as part of alloc_netdev */
1177 	INIT_DELAYED_WORK(&kaweth->lowmem_work, kaweth_resubmit_tl);
1178 	usb_set_intfdata(intf, kaweth);
1179 
1180 #if 0
1181 // dma_supported() is deeply broken on almost all architectures
1182 	if (dma_supported (dev, 0xffffffffffffffffULL))
1183 		kaweth->net->features |= NETIF_F_HIGHDMA;
1184 #endif
1185 
1186 	SET_NETDEV_DEV(netdev, dev);
1187 	if (register_netdev(netdev) != 0) {
1188 		dev_err(dev, "Error registering netdev.\n");
1189 		goto err_intfdata;
1190 	}
1191 
1192 	dev_info(dev, "kaweth interface created at %s\n",
1193 		 kaweth->net->name);
1194 
1195 	dev_dbg(dev, "Kaweth probe returning.\n");
1196 
1197 	return 0;
1198 
1199 err_intfdata:
1200 	usb_set_intfdata(intf, NULL);
1201 	usb_free_coherent(kaweth->dev, KAWETH_BUF_SIZE, (void *)kaweth->rx_buf, kaweth->rxbufferhandle);
1202 err_all_but_rxbuf:
1203 	usb_free_coherent(kaweth->dev, INTBUFFERSIZE, (void *)kaweth->intbuffer, kaweth->intbufferhandle);
1204 err_tx_and_rx_and_irq:
1205 	usb_free_urb(kaweth->irq_urb);
1206 err_tx_and_rx:
1207 	usb_free_urb(kaweth->rx_urb);
1208 err_only_tx:
1209 	usb_free_urb(kaweth->tx_urb);
1210 err_free_netdev:
1211 	free_netdev(netdev);
1212 
1213 	return -EIO;
1214 }
1215 
1216 /****************************************************************
1217  *     kaweth_disconnect
1218  ****************************************************************/
1219 static void kaweth_disconnect(struct usb_interface *intf)
1220 {
1221 	struct kaweth_device *kaweth = usb_get_intfdata(intf);
1222 	struct net_device *netdev;
1223 
1224 	dev_info(&intf->dev, "Unregistering\n");
1225 
1226 	usb_set_intfdata(intf, NULL);
1227 	if (!kaweth) {
1228 		dev_warn(&intf->dev, "unregistering non-existent device\n");
1229 		return;
1230 	}
1231 	netdev = kaweth->net;
1232 
1233 	netdev_dbg(kaweth->net, "Unregistering net device\n");
1234 	unregister_netdev(netdev);
1235 
1236 	usb_free_urb(kaweth->rx_urb);
1237 	usb_free_urb(kaweth->tx_urb);
1238 	usb_free_urb(kaweth->irq_urb);
1239 
1240 	usb_free_coherent(kaweth->dev, KAWETH_BUF_SIZE, (void *)kaweth->rx_buf, kaweth->rxbufferhandle);
1241 	usb_free_coherent(kaweth->dev, INTBUFFERSIZE, (void *)kaweth->intbuffer, kaweth->intbufferhandle);
1242 
1243 	free_netdev(netdev);
1244 }
1245 
1246 
1247 // FIXME this completion stuff is a modified clone of
1248 // an OLD version of some stuff in usb.c ...
1249 struct usb_api_data {
1250 	wait_queue_head_t wqh;
1251 	int done;
1252 };
1253 
1254 /*-------------------------------------------------------------------*
1255  * completion handler for compatibility wrappers (sync control/bulk) *
1256  *-------------------------------------------------------------------*/
1257 static void usb_api_blocking_completion(struct urb *urb)
1258 {
1259         struct usb_api_data *awd = (struct usb_api_data *)urb->context;
1260 
1261 	awd->done=1;
1262 	wake_up(&awd->wqh);
1263 }
1264 
1265 /*-------------------------------------------------------------------*
1266  *                         COMPATIBILITY STUFF                       *
1267  *-------------------------------------------------------------------*/
1268 
1269 // Starts urb and waits for completion or timeout
1270 static int usb_start_wait_urb(struct urb *urb, int timeout, int* actual_length)
1271 {
1272 	struct usb_api_data awd;
1273         int status;
1274 
1275         init_waitqueue_head(&awd.wqh);
1276         awd.done = 0;
1277 
1278         urb->context = &awd;
1279         status = usb_submit_urb(urb, GFP_ATOMIC);
1280         if (status) {
1281                 // something went wrong
1282                 usb_free_urb(urb);
1283                 return status;
1284         }
1285 
1286 	if (!wait_event_timeout(awd.wqh, awd.done, timeout)) {
1287                 // timeout
1288                 dev_warn(&urb->dev->dev, "usb_control/bulk_msg: timeout\n");
1289                 usb_kill_urb(urb);  // remove urb safely
1290                 status = -ETIMEDOUT;
1291         }
1292 	else {
1293                 status = urb->status;
1294 	}
1295 
1296         if (actual_length) {
1297                 *actual_length = urb->actual_length;
1298 	}
1299 
1300         usb_free_urb(urb);
1301         return status;
1302 }
1303 
1304 /*-------------------------------------------------------------------*/
1305 // returns status (negative) or length (positive)
1306 static int kaweth_internal_control_msg(struct usb_device *usb_dev,
1307 				       unsigned int pipe,
1308 				       struct usb_ctrlrequest *cmd, void *data,
1309 				       int len, int timeout)
1310 {
1311         struct urb *urb;
1312         int retv;
1313         int length = 0; /* shut up GCC */
1314 
1315 	urb = usb_alloc_urb(0, GFP_ATOMIC);
1316         if (!urb)
1317                 return -ENOMEM;
1318 
1319         usb_fill_control_urb(urb, usb_dev, pipe, (unsigned char*)cmd, data,
1320 			 len, usb_api_blocking_completion, NULL);
1321 
1322         retv = usb_start_wait_urb(urb, timeout, &length);
1323         if (retv < 0) {
1324                 return retv;
1325 	}
1326         else {
1327                 return length;
1328 	}
1329 }
1330 
1331 module_usb_driver(kaweth_driver);
1332