xref: /openbmc/linux/drivers/net/usb/kaweth.c (revision b830f94f)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /****************************************************************
3  *
4  *     kaweth.c - driver for KL5KUSB101 based USB->Ethernet
5  *
6  *     (c) 2000 Interlan Communications
7  *     (c) 2000 Stephane Alnet
8  *     (C) 2001 Brad Hards
9  *     (C) 2002 Oliver Neukum
10  *
11  *     Original author: The Zapman <zapman@interlan.net>
12  *     Inspired by, and much credit goes to Michael Rothwell
13  *     <rothwell@interlan.net> for the test equipment, help, and patience
14  *     Based off of (and with thanks to) Petko Manolov's pegaus.c driver.
15  *     Also many thanks to Joel Silverman and Ed Surprenant at Kawasaki
16  *     for providing the firmware and driver resources.
17  *
18  ****************************************************************/
19 
20 /* TODO:
21  * Develop test procedures for USB net interfaces
22  * Run test procedures
23  * Fix bugs from previous two steps
24  * Snoop other OSs for any tricks we're not doing
25  * Reduce arbitrary timeouts
26  * Smart multicast support
27  * Temporary MAC change support
28  * Tunable SOFs parameter - ioctl()?
29  * Ethernet stats collection
30  * Code formatting improvements
31  */
32 
33 #include <linux/module.h>
34 #include <linux/slab.h>
35 #include <linux/string.h>
36 #include <linux/delay.h>
37 #include <linux/netdevice.h>
38 #include <linux/etherdevice.h>
39 #include <linux/usb.h>
40 #include <linux/types.h>
41 #include <linux/ethtool.h>
42 #include <linux/dma-mapping.h>
43 #include <linux/wait.h>
44 #include <linux/firmware.h>
45 #include <linux/uaccess.h>
46 #include <asm/byteorder.h>
47 
48 #undef DEBUG
49 
50 #define KAWETH_MTU			1514
51 #define KAWETH_BUF_SIZE			1664
52 #define KAWETH_TX_TIMEOUT		(5 * HZ)
53 #define KAWETH_SCRATCH_SIZE		32
54 #define KAWETH_FIRMWARE_BUF_SIZE	4096
55 #define KAWETH_CONTROL_TIMEOUT		(30000)
56 
57 #define KAWETH_STATUS_BROKEN		0x0000001
58 #define KAWETH_STATUS_CLOSING		0x0000002
59 #define KAWETH_STATUS_SUSPENDING	0x0000004
60 
61 #define KAWETH_STATUS_BLOCKED (KAWETH_STATUS_CLOSING | KAWETH_STATUS_SUSPENDING)
62 
63 #define KAWETH_PACKET_FILTER_PROMISCUOUS	0x01
64 #define KAWETH_PACKET_FILTER_ALL_MULTICAST	0x02
65 #define KAWETH_PACKET_FILTER_DIRECTED		0x04
66 #define KAWETH_PACKET_FILTER_BROADCAST		0x08
67 #define KAWETH_PACKET_FILTER_MULTICAST		0x10
68 
69 /* Table 7 */
70 #define KAWETH_COMMAND_GET_ETHERNET_DESC	0x00
71 #define KAWETH_COMMAND_MULTICAST_FILTERS        0x01
72 #define KAWETH_COMMAND_SET_PACKET_FILTER	0x02
73 #define KAWETH_COMMAND_STATISTICS               0x03
74 #define KAWETH_COMMAND_SET_TEMP_MAC     	0x06
75 #define KAWETH_COMMAND_GET_TEMP_MAC             0x07
76 #define KAWETH_COMMAND_SET_URB_SIZE		0x08
77 #define KAWETH_COMMAND_SET_SOFS_WAIT		0x09
78 #define KAWETH_COMMAND_SCAN			0xFF
79 
80 #define KAWETH_SOFS_TO_WAIT			0x05
81 
82 #define INTBUFFERSIZE				4
83 
84 #define STATE_OFFSET				0
85 #define STATE_MASK				0x40
86 #define	STATE_SHIFT				5
87 
88 #define IS_BLOCKED(s) (s & KAWETH_STATUS_BLOCKED)
89 
90 
91 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>");
92 MODULE_DESCRIPTION("KL5USB101 USB Ethernet driver");
93 MODULE_LICENSE("GPL");
94 MODULE_FIRMWARE("kaweth/new_code.bin");
95 MODULE_FIRMWARE("kaweth/new_code_fix.bin");
96 MODULE_FIRMWARE("kaweth/trigger_code.bin");
97 MODULE_FIRMWARE("kaweth/trigger_code_fix.bin");
98 
99 static const char driver_name[] = "kaweth";
100 
101 static int kaweth_probe(
102 		struct usb_interface *intf,
103 		const struct usb_device_id *id	/* from id_table */
104 	);
105 static void kaweth_disconnect(struct usb_interface *intf);
106 static int kaweth_internal_control_msg(struct usb_device *usb_dev,
107 				       unsigned int pipe,
108 				       struct usb_ctrlrequest *cmd, void *data,
109 				       int len, int timeout);
110 static int kaweth_suspend(struct usb_interface *intf, pm_message_t message);
111 static int kaweth_resume(struct usb_interface *intf);
112 
113 /****************************************************************
114  *     usb_device_id
115  ****************************************************************/
116 static const struct usb_device_id usb_klsi_table[] = {
117 	{ USB_DEVICE(0x03e8, 0x0008) }, /* AOX Endpoints USB Ethernet */
118 	{ USB_DEVICE(0x04bb, 0x0901) }, /* I-O DATA USB-ET/T */
119 	{ USB_DEVICE(0x0506, 0x03e8) }, /* 3Com 3C19250 */
120 	{ USB_DEVICE(0x0506, 0x11f8) }, /* 3Com 3C460 */
121 	{ USB_DEVICE(0x0557, 0x2002) }, /* ATEN USB Ethernet */
122 	{ USB_DEVICE(0x0557, 0x4000) }, /* D-Link DSB-650C */
123 	{ USB_DEVICE(0x0565, 0x0002) }, /* Peracom Enet */
124 	{ USB_DEVICE(0x0565, 0x0003) }, /* Optus@Home UEP1045A */
125 	{ USB_DEVICE(0x0565, 0x0005) }, /* Peracom Enet2 */
126 	{ USB_DEVICE(0x05e9, 0x0008) }, /* KLSI KL5KUSB101B */
127 	{ USB_DEVICE(0x05e9, 0x0009) }, /* KLSI KL5KUSB101B (Board change) */
128 	{ USB_DEVICE(0x066b, 0x2202) }, /* Linksys USB10T */
129 	{ USB_DEVICE(0x06e1, 0x0008) }, /* ADS USB-10BT */
130 	{ USB_DEVICE(0x06e1, 0x0009) }, /* ADS USB-10BT */
131 	{ USB_DEVICE(0x0707, 0x0100) }, /* SMC 2202USB */
132 	{ USB_DEVICE(0x07aa, 0x0001) }, /* Correga K.K. */
133 	{ USB_DEVICE(0x07b8, 0x4000) }, /* D-Link DU-E10 */
134 	{ USB_DEVICE(0x07c9, 0xb010) }, /* Allied Telesyn AT-USB10 USB Ethernet Adapter */
135 	{ USB_DEVICE(0x0846, 0x1001) }, /* NetGear EA-101 */
136 	{ USB_DEVICE(0x0846, 0x1002) }, /* NetGear EA-101 */
137 	{ USB_DEVICE(0x085a, 0x0008) }, /* PortGear Ethernet Adapter */
138 	{ USB_DEVICE(0x085a, 0x0009) }, /* PortGear Ethernet Adapter */
139 	{ USB_DEVICE(0x087d, 0x5704) }, /* Jaton USB Ethernet Device Adapter */
140 	{ USB_DEVICE(0x0951, 0x0008) }, /* Kingston Technology USB Ethernet Adapter */
141 	{ USB_DEVICE(0x095a, 0x3003) }, /* Portsmith Express Ethernet Adapter */
142 	{ USB_DEVICE(0x10bd, 0x1427) }, /* ASANTE USB To Ethernet Adapter */
143 	{ USB_DEVICE(0x1342, 0x0204) }, /* Mobility USB-Ethernet Adapter */
144 	{ USB_DEVICE(0x13d2, 0x0400) }, /* Shark Pocket Adapter */
145 	{ USB_DEVICE(0x1485, 0x0001) },	/* Silicom U2E */
146 	{ USB_DEVICE(0x1485, 0x0002) }, /* Psion Dacom Gold Port Ethernet */
147 	{ USB_DEVICE(0x1645, 0x0005) }, /* Entrega E45 */
148 	{ USB_DEVICE(0x1645, 0x0008) }, /* Entrega USB Ethernet Adapter */
149 	{ USB_DEVICE(0x1645, 0x8005) }, /* PortGear Ethernet Adapter */
150 	{ USB_DEVICE(0x1668, 0x0323) }, /* Actiontec USB Ethernet */
151 	{ USB_DEVICE(0x2001, 0x4000) }, /* D-link DSB-650C */
152 	{} /* Null terminator */
153 };
154 
155 MODULE_DEVICE_TABLE (usb, usb_klsi_table);
156 
157 /****************************************************************
158  *     kaweth_driver
159  ****************************************************************/
160 static struct usb_driver kaweth_driver = {
161 	.name =		driver_name,
162 	.probe =	kaweth_probe,
163 	.disconnect =	kaweth_disconnect,
164 	.suspend =	kaweth_suspend,
165 	.resume =	kaweth_resume,
166 	.id_table =     usb_klsi_table,
167 	.supports_autosuspend =	1,
168 	.disable_hub_initiated_lpm = 1,
169 };
170 
171 typedef __u8 eth_addr_t[6];
172 
173 /****************************************************************
174  *     usb_eth_dev
175  ****************************************************************/
176 struct usb_eth_dev {
177 	char *name;
178 	__u16 vendor;
179 	__u16 device;
180 	void *pdata;
181 };
182 
183 /****************************************************************
184  *     kaweth_ethernet_configuration
185  *     Refer Table 8
186  ****************************************************************/
187 struct kaweth_ethernet_configuration
188 {
189 	__u8 size;
190 	__u8 reserved1;
191 	__u8 reserved2;
192 	eth_addr_t hw_addr;
193 	__u32 statistics_mask;
194 	__le16 segment_size;
195 	__u16 max_multicast_filters;
196 	__u8 reserved3;
197 } __packed;
198 
199 /****************************************************************
200  *     kaweth_device
201  ****************************************************************/
202 struct kaweth_device
203 {
204 	spinlock_t device_lock;
205 
206 	__u32 status;
207 	int end;
208 	int suspend_lowmem_rx;
209 	int suspend_lowmem_ctrl;
210 	int linkstate;
211 	int opened;
212 	struct delayed_work lowmem_work;
213 
214 	struct usb_device *dev;
215 	struct usb_interface *intf;
216 	struct net_device *net;
217 	wait_queue_head_t term_wait;
218 
219 	struct urb *rx_urb;
220 	struct urb *tx_urb;
221 	struct urb *irq_urb;
222 
223 	dma_addr_t intbufferhandle;
224 	__u8 *intbuffer;
225 	dma_addr_t rxbufferhandle;
226 	__u8 *rx_buf;
227 
228 
229 	struct sk_buff *tx_skb;
230 
231 	__u8 *firmware_buf;
232 	__u8 scratch[KAWETH_SCRATCH_SIZE];
233 	__u16 packet_filter_bitmap;
234 
235 	struct kaweth_ethernet_configuration configuration;
236 };
237 
238 /****************************************************************
239  *     kaweth_control
240  ****************************************************************/
241 static int kaweth_control(struct kaweth_device *kaweth,
242 			  unsigned int pipe,
243 			  __u8 request,
244 			  __u8 requesttype,
245 			  __u16 value,
246 			  __u16 index,
247 			  void *data,
248 			  __u16 size,
249 			  int timeout)
250 {
251 	struct usb_ctrlrequest *dr;
252 	int retval;
253 
254 	if(in_interrupt()) {
255 		netdev_dbg(kaweth->net, "in_interrupt()\n");
256 		return -EBUSY;
257 	}
258 
259 	dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
260 	if (!dr)
261 		return -ENOMEM;
262 
263 	dr->bRequestType = requesttype;
264 	dr->bRequest = request;
265 	dr->wValue = cpu_to_le16(value);
266 	dr->wIndex = cpu_to_le16(index);
267 	dr->wLength = cpu_to_le16(size);
268 
269 	retval = kaweth_internal_control_msg(kaweth->dev,
270 					     pipe,
271 					     dr,
272 					     data,
273 					     size,
274 					     timeout);
275 
276 	kfree(dr);
277 	return retval;
278 }
279 
280 /****************************************************************
281  *     kaweth_read_configuration
282  ****************************************************************/
283 static int kaweth_read_configuration(struct kaweth_device *kaweth)
284 {
285 	int retval;
286 
287 	retval = kaweth_control(kaweth,
288 				usb_rcvctrlpipe(kaweth->dev, 0),
289 				KAWETH_COMMAND_GET_ETHERNET_DESC,
290 				USB_TYPE_VENDOR | USB_DIR_IN | USB_RECIP_DEVICE,
291 				0,
292 				0,
293 				(void *)&kaweth->configuration,
294 				sizeof(kaweth->configuration),
295 				KAWETH_CONTROL_TIMEOUT);
296 
297 	return retval;
298 }
299 
300 /****************************************************************
301  *     kaweth_set_urb_size
302  ****************************************************************/
303 static int kaweth_set_urb_size(struct kaweth_device *kaweth, __u16 urb_size)
304 {
305 	int retval;
306 
307 	netdev_dbg(kaweth->net, "Setting URB size to %d\n", (unsigned)urb_size);
308 
309 	retval = kaweth_control(kaweth,
310 				usb_sndctrlpipe(kaweth->dev, 0),
311 				KAWETH_COMMAND_SET_URB_SIZE,
312 				USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE,
313 				urb_size,
314 				0,
315 				(void *)&kaweth->scratch,
316 				0,
317 				KAWETH_CONTROL_TIMEOUT);
318 
319 	return retval;
320 }
321 
322 /****************************************************************
323  *     kaweth_set_sofs_wait
324  ****************************************************************/
325 static int kaweth_set_sofs_wait(struct kaweth_device *kaweth, __u16 sofs_wait)
326 {
327 	int retval;
328 
329 	netdev_dbg(kaweth->net, "Set SOFS wait to %d\n", (unsigned)sofs_wait);
330 
331 	retval = kaweth_control(kaweth,
332 				usb_sndctrlpipe(kaweth->dev, 0),
333 				KAWETH_COMMAND_SET_SOFS_WAIT,
334 				USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE,
335 				sofs_wait,
336 				0,
337 				(void *)&kaweth->scratch,
338 				0,
339 				KAWETH_CONTROL_TIMEOUT);
340 
341 	return retval;
342 }
343 
344 /****************************************************************
345  *     kaweth_set_receive_filter
346  ****************************************************************/
347 static int kaweth_set_receive_filter(struct kaweth_device *kaweth,
348 				     __u16 receive_filter)
349 {
350 	int retval;
351 
352 	netdev_dbg(kaweth->net, "Set receive filter to %d\n",
353 		   (unsigned)receive_filter);
354 
355 	retval = kaweth_control(kaweth,
356 				usb_sndctrlpipe(kaweth->dev, 0),
357 				KAWETH_COMMAND_SET_PACKET_FILTER,
358 				USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE,
359 				receive_filter,
360 				0,
361 				(void *)&kaweth->scratch,
362 				0,
363 				KAWETH_CONTROL_TIMEOUT);
364 
365 	return retval;
366 }
367 
368 /****************************************************************
369  *     kaweth_download_firmware
370  ****************************************************************/
371 static int kaweth_download_firmware(struct kaweth_device *kaweth,
372 				    const char *fwname,
373 				    __u8 interrupt,
374 				    __u8 type)
375 {
376 	const struct firmware *fw;
377 	int data_len;
378 	int ret;
379 
380 	ret = request_firmware(&fw, fwname, &kaweth->dev->dev);
381 	if (ret) {
382 		dev_err(&kaweth->intf->dev, "Firmware request failed\n");
383 		return ret;
384 	}
385 
386 	if (fw->size > KAWETH_FIRMWARE_BUF_SIZE) {
387 		dev_err(&kaweth->intf->dev, "Firmware too big: %zu\n",
388 			fw->size);
389 		release_firmware(fw);
390 		return -ENOSPC;
391 	}
392 	data_len = fw->size;
393 	memcpy(kaweth->firmware_buf, fw->data, fw->size);
394 
395 	release_firmware(fw);
396 
397 	kaweth->firmware_buf[2] = (data_len & 0xFF) - 7;
398 	kaweth->firmware_buf[3] = data_len >> 8;
399 	kaweth->firmware_buf[4] = type;
400 	kaweth->firmware_buf[5] = interrupt;
401 
402 	netdev_dbg(kaweth->net, "High: %i, Low:%i\n", kaweth->firmware_buf[3],
403 		   kaweth->firmware_buf[2]);
404 
405 	netdev_dbg(kaweth->net,
406 		   "Downloading firmware at %p to kaweth device at %p\n",
407 		   kaweth->firmware_buf, kaweth);
408 	netdev_dbg(kaweth->net, "Firmware length: %d\n", data_len);
409 
410 	return kaweth_control(kaweth,
411 		              usb_sndctrlpipe(kaweth->dev, 0),
412 			      KAWETH_COMMAND_SCAN,
413 			      USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE,
414 			      0,
415 			      0,
416 			      (void *)kaweth->firmware_buf,
417 			      data_len,
418 			      KAWETH_CONTROL_TIMEOUT);
419 }
420 
421 /****************************************************************
422  *     kaweth_trigger_firmware
423  ****************************************************************/
424 static int kaweth_trigger_firmware(struct kaweth_device *kaweth,
425 				   __u8 interrupt)
426 {
427 	kaweth->firmware_buf[0] = 0xB6;
428 	kaweth->firmware_buf[1] = 0xC3;
429 	kaweth->firmware_buf[2] = 0x01;
430 	kaweth->firmware_buf[3] = 0x00;
431 	kaweth->firmware_buf[4] = 0x06;
432 	kaweth->firmware_buf[5] = interrupt;
433 	kaweth->firmware_buf[6] = 0x00;
434 	kaweth->firmware_buf[7] = 0x00;
435 
436 	return kaweth_control(kaweth,
437 			      usb_sndctrlpipe(kaweth->dev, 0),
438 			      KAWETH_COMMAND_SCAN,
439 			      USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE,
440 			      0,
441 			      0,
442 			      (void *)kaweth->firmware_buf,
443 			      8,
444 			      KAWETH_CONTROL_TIMEOUT);
445 }
446 
447 /****************************************************************
448  *     kaweth_reset
449  ****************************************************************/
450 static int kaweth_reset(struct kaweth_device *kaweth)
451 {
452 	int result;
453 
454 	result = usb_reset_configuration(kaweth->dev);
455 	mdelay(10);
456 
457 	netdev_dbg(kaweth->net, "kaweth_reset() returns %d.\n", result);
458 
459 	return result;
460 }
461 
462 static void kaweth_usb_receive(struct urb *);
463 static int kaweth_resubmit_rx_urb(struct kaweth_device *, gfp_t);
464 
465 /****************************************************************
466 	int_callback
467 *****************************************************************/
468 
469 static void kaweth_resubmit_int_urb(struct kaweth_device *kaweth, gfp_t mf)
470 {
471 	int status;
472 
473 	status = usb_submit_urb (kaweth->irq_urb, mf);
474 	if (unlikely(status == -ENOMEM)) {
475 		kaweth->suspend_lowmem_ctrl = 1;
476 		schedule_delayed_work(&kaweth->lowmem_work, HZ/4);
477 	} else {
478 		kaweth->suspend_lowmem_ctrl = 0;
479 	}
480 
481 	if (status)
482 		dev_err(&kaweth->intf->dev,
483 			"can't resubmit intr, %s-%s, status %d\n",
484 			kaweth->dev->bus->bus_name,
485 			kaweth->dev->devpath, status);
486 }
487 
488 static void int_callback(struct urb *u)
489 {
490 	struct kaweth_device *kaweth = u->context;
491 	int act_state;
492 	int status = u->status;
493 
494 	switch (status) {
495 	case 0:			/* success */
496 		break;
497 	case -ECONNRESET:	/* unlink */
498 	case -ENOENT:
499 	case -ESHUTDOWN:
500 		return;
501 	/* -EPIPE:  should clear the halt */
502 	default:		/* error */
503 		goto resubmit;
504 	}
505 
506 	/* we check the link state to report changes */
507 	if (kaweth->linkstate != (act_state = ( kaweth->intbuffer[STATE_OFFSET] | STATE_MASK) >> STATE_SHIFT)) {
508 		if (act_state)
509 			netif_carrier_on(kaweth->net);
510 		else
511 			netif_carrier_off(kaweth->net);
512 
513 		kaweth->linkstate = act_state;
514 	}
515 resubmit:
516 	kaweth_resubmit_int_urb(kaweth, GFP_ATOMIC);
517 }
518 
519 static void kaweth_resubmit_tl(struct work_struct *work)
520 {
521 	struct kaweth_device *kaweth =
522 		container_of(work, struct kaweth_device, lowmem_work.work);
523 
524 	if (IS_BLOCKED(kaweth->status))
525 		return;
526 
527 	if (kaweth->suspend_lowmem_rx)
528 		kaweth_resubmit_rx_urb(kaweth, GFP_NOIO);
529 
530 	if (kaweth->suspend_lowmem_ctrl)
531 		kaweth_resubmit_int_urb(kaweth, GFP_NOIO);
532 }
533 
534 
535 /****************************************************************
536  *     kaweth_resubmit_rx_urb
537  ****************************************************************/
538 static int kaweth_resubmit_rx_urb(struct kaweth_device *kaweth,
539 						gfp_t mem_flags)
540 {
541 	int result;
542 
543 	usb_fill_bulk_urb(kaweth->rx_urb,
544 		      kaweth->dev,
545 		      usb_rcvbulkpipe(kaweth->dev, 1),
546 		      kaweth->rx_buf,
547 		      KAWETH_BUF_SIZE,
548 		      kaweth_usb_receive,
549 		      kaweth);
550 	kaweth->rx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
551 	kaweth->rx_urb->transfer_dma = kaweth->rxbufferhandle;
552 
553 	if((result = usb_submit_urb(kaweth->rx_urb, mem_flags))) {
554 		if (result == -ENOMEM) {
555 			kaweth->suspend_lowmem_rx = 1;
556 			schedule_delayed_work(&kaweth->lowmem_work, HZ/4);
557 		}
558 		dev_err(&kaweth->intf->dev, "resubmitting rx_urb %d failed\n",
559 			result);
560 	} else {
561 		kaweth->suspend_lowmem_rx = 0;
562 	}
563 
564 	return result;
565 }
566 
567 static void kaweth_async_set_rx_mode(struct kaweth_device *kaweth);
568 
569 /****************************************************************
570  *     kaweth_usb_receive
571  ****************************************************************/
572 static void kaweth_usb_receive(struct urb *urb)
573 {
574 	struct device *dev = &urb->dev->dev;
575 	struct kaweth_device *kaweth = urb->context;
576 	struct net_device *net = kaweth->net;
577 	int status = urb->status;
578 	unsigned long flags;
579 	int count = urb->actual_length;
580 	int count2 = urb->transfer_buffer_length;
581 
582 	__u16 pkt_len = le16_to_cpup((__le16 *)kaweth->rx_buf);
583 
584 	struct sk_buff *skb;
585 
586 	if (unlikely(status == -EPIPE)) {
587 		net->stats.rx_errors++;
588 		kaweth->end = 1;
589 		wake_up(&kaweth->term_wait);
590 		dev_dbg(dev, "Status was -EPIPE.\n");
591 		return;
592 	}
593 	if (unlikely(status == -ECONNRESET || status == -ESHUTDOWN)) {
594 		/* we are killed - set a flag and wake the disconnect handler */
595 		kaweth->end = 1;
596 		wake_up(&kaweth->term_wait);
597 		dev_dbg(dev, "Status was -ECONNRESET or -ESHUTDOWN.\n");
598 		return;
599 	}
600 	if (unlikely(status == -EPROTO || status == -ETIME ||
601 		     status == -EILSEQ)) {
602 		net->stats.rx_errors++;
603 		dev_dbg(dev, "Status was -EPROTO, -ETIME, or -EILSEQ.\n");
604 		return;
605 	}
606 	if (unlikely(status == -EOVERFLOW)) {
607 		net->stats.rx_errors++;
608 		dev_dbg(dev, "Status was -EOVERFLOW.\n");
609 	}
610 	spin_lock_irqsave(&kaweth->device_lock, flags);
611 	if (IS_BLOCKED(kaweth->status)) {
612 		spin_unlock_irqrestore(&kaweth->device_lock, flags);
613 		return;
614 	}
615 	spin_unlock_irqrestore(&kaweth->device_lock, flags);
616 
617 	if(status && status != -EREMOTEIO && count != 1) {
618 		dev_err(&kaweth->intf->dev,
619 			"%s RX status: %d count: %d packet_len: %d\n",
620 			net->name, status, count, (int)pkt_len);
621 		kaweth_resubmit_rx_urb(kaweth, GFP_ATOMIC);
622                 return;
623 	}
624 
625 	if(kaweth->net && (count > 2)) {
626 		if(pkt_len > (count - 2)) {
627 			dev_err(&kaweth->intf->dev,
628 				"Packet length too long for USB frame (pkt_len: %x, count: %x)\n",
629 				pkt_len, count);
630 			dev_err(&kaweth->intf->dev, "Packet len & 2047: %x\n",
631 				pkt_len & 2047);
632 			dev_err(&kaweth->intf->dev, "Count 2: %x\n", count2);
633 		        kaweth_resubmit_rx_urb(kaweth, GFP_ATOMIC);
634                         return;
635                 }
636 
637 		if(!(skb = dev_alloc_skb(pkt_len+2))) {
638 		        kaweth_resubmit_rx_urb(kaweth, GFP_ATOMIC);
639                         return;
640 		}
641 
642 		skb_reserve(skb, 2);    /* Align IP on 16 byte boundaries */
643 
644 		skb_copy_to_linear_data(skb, kaweth->rx_buf + 2, pkt_len);
645 
646 		skb_put(skb, pkt_len);
647 
648 		skb->protocol = eth_type_trans(skb, net);
649 
650 		netif_rx(skb);
651 
652 		net->stats.rx_packets++;
653 		net->stats.rx_bytes += pkt_len;
654 	}
655 
656 	kaweth_resubmit_rx_urb(kaweth, GFP_ATOMIC);
657 }
658 
659 /****************************************************************
660  *     kaweth_open
661  ****************************************************************/
662 static int kaweth_open(struct net_device *net)
663 {
664 	struct kaweth_device *kaweth = netdev_priv(net);
665 	int res;
666 
667 	res = usb_autopm_get_interface(kaweth->intf);
668 	if (res) {
669 		dev_err(&kaweth->intf->dev, "Interface cannot be resumed.\n");
670 		return -EIO;
671 	}
672 	res = kaweth_resubmit_rx_urb(kaweth, GFP_KERNEL);
673 	if (res)
674 		goto err_out;
675 
676 	usb_fill_int_urb(
677 		kaweth->irq_urb,
678 		kaweth->dev,
679 		usb_rcvintpipe(kaweth->dev, 3),
680 		kaweth->intbuffer,
681 		INTBUFFERSIZE,
682 		int_callback,
683 		kaweth,
684 		250); /* overriding the descriptor */
685 	kaweth->irq_urb->transfer_dma = kaweth->intbufferhandle;
686 	kaweth->irq_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
687 
688 	res = usb_submit_urb(kaweth->irq_urb, GFP_KERNEL);
689 	if (res) {
690 		usb_kill_urb(kaweth->rx_urb);
691 		goto err_out;
692 	}
693 	kaweth->opened = 1;
694 
695 	netif_start_queue(net);
696 
697 	kaweth_async_set_rx_mode(kaweth);
698 	return 0;
699 
700 err_out:
701 	usb_autopm_put_interface(kaweth->intf);
702 	return -EIO;
703 }
704 
705 /****************************************************************
706  *     kaweth_kill_urbs
707  ****************************************************************/
708 static void kaweth_kill_urbs(struct kaweth_device *kaweth)
709 {
710 	usb_kill_urb(kaweth->irq_urb);
711 	usb_kill_urb(kaweth->rx_urb);
712 	usb_kill_urb(kaweth->tx_urb);
713 
714 	cancel_delayed_work_sync(&kaweth->lowmem_work);
715 
716 	/* a scheduled work may have resubmitted,
717 	   we hit them again */
718 	usb_kill_urb(kaweth->irq_urb);
719 	usb_kill_urb(kaweth->rx_urb);
720 }
721 
722 /****************************************************************
723  *     kaweth_close
724  ****************************************************************/
725 static int kaweth_close(struct net_device *net)
726 {
727 	struct kaweth_device *kaweth = netdev_priv(net);
728 
729 	netif_stop_queue(net);
730 	kaweth->opened = 0;
731 
732 	kaweth->status |= KAWETH_STATUS_CLOSING;
733 
734 	kaweth_kill_urbs(kaweth);
735 
736 	kaweth->status &= ~KAWETH_STATUS_CLOSING;
737 
738 	usb_autopm_put_interface(kaweth->intf);
739 
740 	return 0;
741 }
742 
743 static u32 kaweth_get_link(struct net_device *dev)
744 {
745 	struct kaweth_device *kaweth = netdev_priv(dev);
746 
747 	return kaweth->linkstate;
748 }
749 
750 static const struct ethtool_ops ops = {
751 	.get_link	= kaweth_get_link
752 };
753 
754 /****************************************************************
755  *     kaweth_usb_transmit_complete
756  ****************************************************************/
757 static void kaweth_usb_transmit_complete(struct urb *urb)
758 {
759 	struct kaweth_device *kaweth = urb->context;
760 	struct sk_buff *skb = kaweth->tx_skb;
761 	int status = urb->status;
762 
763 	if (unlikely(status != 0))
764 		if (status != -ENOENT)
765 			dev_dbg(&urb->dev->dev, "%s: TX status %d.\n",
766 				kaweth->net->name, status);
767 
768 	netif_wake_queue(kaweth->net);
769 	dev_kfree_skb_irq(skb);
770 }
771 
772 /****************************************************************
773  *     kaweth_start_xmit
774  ****************************************************************/
775 static netdev_tx_t kaweth_start_xmit(struct sk_buff *skb,
776 					   struct net_device *net)
777 {
778 	struct kaweth_device *kaweth = netdev_priv(net);
779 	__le16 *private_header;
780 
781 	int res;
782 
783 	spin_lock_irq(&kaweth->device_lock);
784 
785 	kaweth_async_set_rx_mode(kaweth);
786 	netif_stop_queue(net);
787 	if (IS_BLOCKED(kaweth->status)) {
788 		goto skip;
789 	}
790 
791 	/* We now decide whether we can put our special header into the sk_buff */
792 	if (skb_cow_head(skb, 2)) {
793 		net->stats.tx_errors++;
794 		netif_start_queue(net);
795 		spin_unlock_irq(&kaweth->device_lock);
796 		dev_kfree_skb_any(skb);
797 		return NETDEV_TX_OK;
798 	}
799 
800 	private_header = __skb_push(skb, 2);
801 	*private_header = cpu_to_le16(skb->len-2);
802 	kaweth->tx_skb = skb;
803 
804 	usb_fill_bulk_urb(kaweth->tx_urb,
805 		      kaweth->dev,
806 		      usb_sndbulkpipe(kaweth->dev, 2),
807 		      private_header,
808 		      skb->len,
809 		      kaweth_usb_transmit_complete,
810 		      kaweth);
811 	kaweth->end = 0;
812 
813 	if((res = usb_submit_urb(kaweth->tx_urb, GFP_ATOMIC)))
814 	{
815 		dev_warn(&net->dev, "kaweth failed tx_urb %d\n", res);
816 skip:
817 		net->stats.tx_errors++;
818 
819 		netif_start_queue(net);
820 		dev_kfree_skb_irq(skb);
821 	}
822 	else
823 	{
824 		net->stats.tx_packets++;
825 		net->stats.tx_bytes += skb->len;
826 	}
827 
828 	spin_unlock_irq(&kaweth->device_lock);
829 
830 	return NETDEV_TX_OK;
831 }
832 
833 /****************************************************************
834  *     kaweth_set_rx_mode
835  ****************************************************************/
836 static void kaweth_set_rx_mode(struct net_device *net)
837 {
838 	struct kaweth_device *kaweth = netdev_priv(net);
839 
840 	__u16 packet_filter_bitmap = KAWETH_PACKET_FILTER_DIRECTED |
841                                      KAWETH_PACKET_FILTER_BROADCAST |
842 		                     KAWETH_PACKET_FILTER_MULTICAST;
843 
844 	netdev_dbg(net, "Setting Rx mode to %d\n", packet_filter_bitmap);
845 
846 	netif_stop_queue(net);
847 
848 	if (net->flags & IFF_PROMISC) {
849 		packet_filter_bitmap |= KAWETH_PACKET_FILTER_PROMISCUOUS;
850 	}
851 	else if (!netdev_mc_empty(net) || (net->flags & IFF_ALLMULTI)) {
852 		packet_filter_bitmap |= KAWETH_PACKET_FILTER_ALL_MULTICAST;
853 	}
854 
855 	kaweth->packet_filter_bitmap = packet_filter_bitmap;
856 	netif_wake_queue(net);
857 }
858 
859 /****************************************************************
860  *     kaweth_async_set_rx_mode
861  ****************************************************************/
862 static void kaweth_async_set_rx_mode(struct kaweth_device *kaweth)
863 {
864 	int result;
865 	__u16 packet_filter_bitmap = kaweth->packet_filter_bitmap;
866 
867 	kaweth->packet_filter_bitmap = 0;
868 	if (packet_filter_bitmap == 0)
869 		return;
870 
871 	if (in_interrupt())
872 		return;
873 
874 	result = kaweth_control(kaweth,
875 				usb_sndctrlpipe(kaweth->dev, 0),
876 				KAWETH_COMMAND_SET_PACKET_FILTER,
877 				USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE,
878 				packet_filter_bitmap,
879 				0,
880 				(void *)&kaweth->scratch,
881 				0,
882 				KAWETH_CONTROL_TIMEOUT);
883 
884 	if(result < 0) {
885 		dev_err(&kaweth->intf->dev, "Failed to set Rx mode: %d\n",
886 			result);
887 	}
888 	else {
889 		netdev_dbg(kaweth->net, "Set Rx mode to %d\n",
890 			   packet_filter_bitmap);
891 	}
892 }
893 
894 /****************************************************************
895  *     kaweth_tx_timeout
896  ****************************************************************/
897 static void kaweth_tx_timeout(struct net_device *net)
898 {
899 	struct kaweth_device *kaweth = netdev_priv(net);
900 
901 	dev_warn(&net->dev, "%s: Tx timed out. Resetting.\n", net->name);
902 	net->stats.tx_errors++;
903 	netif_trans_update(net);
904 
905 	usb_unlink_urb(kaweth->tx_urb);
906 }
907 
908 /****************************************************************
909  *     kaweth_suspend
910  ****************************************************************/
911 static int kaweth_suspend(struct usb_interface *intf, pm_message_t message)
912 {
913 	struct kaweth_device *kaweth = usb_get_intfdata(intf);
914 	unsigned long flags;
915 
916 	spin_lock_irqsave(&kaweth->device_lock, flags);
917 	kaweth->status |= KAWETH_STATUS_SUSPENDING;
918 	spin_unlock_irqrestore(&kaweth->device_lock, flags);
919 
920 	kaweth_kill_urbs(kaweth);
921 	return 0;
922 }
923 
924 /****************************************************************
925  *     kaweth_resume
926  ****************************************************************/
927 static int kaweth_resume(struct usb_interface *intf)
928 {
929 	struct kaweth_device *kaweth = usb_get_intfdata(intf);
930 	unsigned long flags;
931 
932 	spin_lock_irqsave(&kaweth->device_lock, flags);
933 	kaweth->status &= ~KAWETH_STATUS_SUSPENDING;
934 	spin_unlock_irqrestore(&kaweth->device_lock, flags);
935 
936 	if (!kaweth->opened)
937 		return 0;
938 	kaweth_resubmit_rx_urb(kaweth, GFP_NOIO);
939 	kaweth_resubmit_int_urb(kaweth, GFP_NOIO);
940 
941 	return 0;
942 }
943 
944 /****************************************************************
945  *     kaweth_probe
946  ****************************************************************/
947 
948 
949 static const struct net_device_ops kaweth_netdev_ops = {
950 	.ndo_open =			kaweth_open,
951 	.ndo_stop =			kaweth_close,
952 	.ndo_start_xmit =		kaweth_start_xmit,
953 	.ndo_tx_timeout =		kaweth_tx_timeout,
954 	.ndo_set_rx_mode =		kaweth_set_rx_mode,
955 	.ndo_set_mac_address =		eth_mac_addr,
956 	.ndo_validate_addr =		eth_validate_addr,
957 };
958 
959 static int kaweth_probe(
960 		struct usb_interface *intf,
961 		const struct usb_device_id *id      /* from id_table */
962 	)
963 {
964 	struct device *dev = &intf->dev;
965 	struct usb_device *udev = interface_to_usbdev(intf);
966 	struct kaweth_device *kaweth;
967 	struct net_device *netdev;
968 	const eth_addr_t bcast_addr = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
969 	int result = 0;
970 	int rv = -EIO;
971 
972 	dev_dbg(dev,
973 		"Kawasaki Device Probe (Device number:%d): 0x%4.4x:0x%4.4x:0x%4.4x\n",
974 		udev->devnum, le16_to_cpu(udev->descriptor.idVendor),
975 		le16_to_cpu(udev->descriptor.idProduct),
976 		le16_to_cpu(udev->descriptor.bcdDevice));
977 
978 	dev_dbg(dev, "Device at %p\n", udev);
979 
980 	dev_dbg(dev, "Descriptor length: %x type: %x\n",
981 		(int)udev->descriptor.bLength,
982 		(int)udev->descriptor.bDescriptorType);
983 
984 	netdev = alloc_etherdev(sizeof(*kaweth));
985 	if (!netdev)
986 		return -ENOMEM;
987 
988 	kaweth = netdev_priv(netdev);
989 	kaweth->dev = udev;
990 	kaweth->net = netdev;
991 	kaweth->intf = intf;
992 
993 	spin_lock_init(&kaweth->device_lock);
994 	init_waitqueue_head(&kaweth->term_wait);
995 
996 	dev_dbg(dev, "Resetting.\n");
997 
998 	kaweth_reset(kaweth);
999 
1000 	/*
1001 	 * If high byte of bcdDevice is nonzero, firmware is already
1002 	 * downloaded. Don't try to do it again, or we'll hang the device.
1003 	 */
1004 
1005 	if (le16_to_cpu(udev->descriptor.bcdDevice) >> 8) {
1006 		dev_info(dev, "Firmware present in device.\n");
1007 	} else {
1008 		/* Download the firmware */
1009 		dev_info(dev, "Downloading firmware...\n");
1010 		kaweth->firmware_buf = (__u8 *)__get_free_page(GFP_KERNEL);
1011 		if (!kaweth->firmware_buf) {
1012 			rv = -ENOMEM;
1013 			goto err_free_netdev;
1014 		}
1015 		if ((result = kaweth_download_firmware(kaweth,
1016 						      "kaweth/new_code.bin",
1017 						      100,
1018 						      2)) < 0) {
1019 			dev_err(dev, "Error downloading firmware (%d)\n",
1020 				result);
1021 			goto err_fw;
1022 		}
1023 
1024 		if ((result = kaweth_download_firmware(kaweth,
1025 						      "kaweth/new_code_fix.bin",
1026 						      100,
1027 						      3)) < 0) {
1028 			dev_err(dev, "Error downloading firmware fix (%d)\n",
1029 				result);
1030 			goto err_fw;
1031 		}
1032 
1033 		if ((result = kaweth_download_firmware(kaweth,
1034 						      "kaweth/trigger_code.bin",
1035 						      126,
1036 						      2)) < 0) {
1037 			dev_err(dev, "Error downloading trigger code (%d)\n",
1038 				result);
1039 			goto err_fw;
1040 
1041 		}
1042 
1043 		if ((result = kaweth_download_firmware(kaweth,
1044 						      "kaweth/trigger_code_fix.bin",
1045 						      126,
1046 						      3)) < 0) {
1047 			dev_err(dev, "Error downloading trigger code fix (%d)\n", result);
1048 			goto err_fw;
1049 		}
1050 
1051 
1052 		if ((result = kaweth_trigger_firmware(kaweth, 126)) < 0) {
1053 			dev_err(dev, "Error triggering firmware (%d)\n", result);
1054 			goto err_fw;
1055 		}
1056 
1057 		/* Device will now disappear for a moment...  */
1058 		dev_info(dev, "Firmware loaded.  I'll be back...\n");
1059 err_fw:
1060 		free_page((unsigned long)kaweth->firmware_buf);
1061 		free_netdev(netdev);
1062 		return -EIO;
1063 	}
1064 
1065 	result = kaweth_read_configuration(kaweth);
1066 
1067 	if(result < 0) {
1068 		dev_err(dev, "Error reading configuration (%d), no net device created\n", result);
1069 		goto err_free_netdev;
1070 	}
1071 
1072 	dev_info(dev, "Statistics collection: %x\n", kaweth->configuration.statistics_mask);
1073 	dev_info(dev, "Multicast filter limit: %x\n", kaweth->configuration.max_multicast_filters & ((1 << 15) - 1));
1074 	dev_info(dev, "MTU: %d\n", le16_to_cpu(kaweth->configuration.segment_size));
1075 	dev_info(dev, "Read MAC address %pM\n", kaweth->configuration.hw_addr);
1076 
1077 	if(!memcmp(&kaweth->configuration.hw_addr,
1078                    &bcast_addr,
1079 		   sizeof(bcast_addr))) {
1080 		dev_err(dev, "Firmware not functioning properly, no net device created\n");
1081 		goto err_free_netdev;
1082 	}
1083 
1084 	if(kaweth_set_urb_size(kaweth, KAWETH_BUF_SIZE) < 0) {
1085 		dev_dbg(dev, "Error setting URB size\n");
1086 		goto err_free_netdev;
1087 	}
1088 
1089 	if(kaweth_set_sofs_wait(kaweth, KAWETH_SOFS_TO_WAIT) < 0) {
1090 		dev_err(dev, "Error setting SOFS wait\n");
1091 		goto err_free_netdev;
1092 	}
1093 
1094 	result = kaweth_set_receive_filter(kaweth,
1095                                            KAWETH_PACKET_FILTER_DIRECTED |
1096                                            KAWETH_PACKET_FILTER_BROADCAST |
1097                                            KAWETH_PACKET_FILTER_MULTICAST);
1098 
1099 	if(result < 0) {
1100 		dev_err(dev, "Error setting receive filter\n");
1101 		goto err_free_netdev;
1102 	}
1103 
1104 	dev_dbg(dev, "Initializing net device.\n");
1105 
1106 	kaweth->tx_urb = usb_alloc_urb(0, GFP_KERNEL);
1107 	if (!kaweth->tx_urb)
1108 		goto err_free_netdev;
1109 	kaweth->rx_urb = usb_alloc_urb(0, GFP_KERNEL);
1110 	if (!kaweth->rx_urb)
1111 		goto err_only_tx;
1112 	kaweth->irq_urb = usb_alloc_urb(0, GFP_KERNEL);
1113 	if (!kaweth->irq_urb)
1114 		goto err_tx_and_rx;
1115 
1116 	kaweth->intbuffer = usb_alloc_coherent(	kaweth->dev,
1117 						INTBUFFERSIZE,
1118 						GFP_KERNEL,
1119 						&kaweth->intbufferhandle);
1120 	if (!kaweth->intbuffer)
1121 		goto err_tx_and_rx_and_irq;
1122 	kaweth->rx_buf = usb_alloc_coherent(	kaweth->dev,
1123 						KAWETH_BUF_SIZE,
1124 						GFP_KERNEL,
1125 						&kaweth->rxbufferhandle);
1126 	if (!kaweth->rx_buf)
1127 		goto err_all_but_rxbuf;
1128 
1129 	memcpy(netdev->broadcast, &bcast_addr, sizeof(bcast_addr));
1130 	memcpy(netdev->dev_addr, &kaweth->configuration.hw_addr,
1131                sizeof(kaweth->configuration.hw_addr));
1132 
1133 	netdev->netdev_ops = &kaweth_netdev_ops;
1134 	netdev->watchdog_timeo = KAWETH_TX_TIMEOUT;
1135 	netdev->mtu = le16_to_cpu(kaweth->configuration.segment_size);
1136 	netdev->ethtool_ops = &ops;
1137 
1138 	/* kaweth is zeroed as part of alloc_netdev */
1139 	INIT_DELAYED_WORK(&kaweth->lowmem_work, kaweth_resubmit_tl);
1140 	usb_set_intfdata(intf, kaweth);
1141 
1142 	SET_NETDEV_DEV(netdev, dev);
1143 	if (register_netdev(netdev) != 0) {
1144 		dev_err(dev, "Error registering netdev.\n");
1145 		goto err_intfdata;
1146 	}
1147 
1148 	dev_info(dev, "kaweth interface created at %s\n",
1149 		 kaweth->net->name);
1150 
1151 	return 0;
1152 
1153 err_intfdata:
1154 	usb_set_intfdata(intf, NULL);
1155 	usb_free_coherent(kaweth->dev, KAWETH_BUF_SIZE, (void *)kaweth->rx_buf, kaweth->rxbufferhandle);
1156 err_all_but_rxbuf:
1157 	usb_free_coherent(kaweth->dev, INTBUFFERSIZE, (void *)kaweth->intbuffer, kaweth->intbufferhandle);
1158 err_tx_and_rx_and_irq:
1159 	usb_free_urb(kaweth->irq_urb);
1160 err_tx_and_rx:
1161 	usb_free_urb(kaweth->rx_urb);
1162 err_only_tx:
1163 	usb_free_urb(kaweth->tx_urb);
1164 err_free_netdev:
1165 	free_netdev(netdev);
1166 
1167 	return rv;
1168 }
1169 
1170 /****************************************************************
1171  *     kaweth_disconnect
1172  ****************************************************************/
1173 static void kaweth_disconnect(struct usb_interface *intf)
1174 {
1175 	struct kaweth_device *kaweth = usb_get_intfdata(intf);
1176 	struct net_device *netdev;
1177 
1178 	usb_set_intfdata(intf, NULL);
1179 	if (!kaweth) {
1180 		dev_warn(&intf->dev, "unregistering non-existent device\n");
1181 		return;
1182 	}
1183 	netdev = kaweth->net;
1184 
1185 	netdev_dbg(kaweth->net, "Unregistering net device\n");
1186 	unregister_netdev(netdev);
1187 
1188 	usb_free_urb(kaweth->rx_urb);
1189 	usb_free_urb(kaweth->tx_urb);
1190 	usb_free_urb(kaweth->irq_urb);
1191 
1192 	usb_free_coherent(kaweth->dev, KAWETH_BUF_SIZE, (void *)kaweth->rx_buf, kaweth->rxbufferhandle);
1193 	usb_free_coherent(kaweth->dev, INTBUFFERSIZE, (void *)kaweth->intbuffer, kaweth->intbufferhandle);
1194 
1195 	free_netdev(netdev);
1196 }
1197 
1198 
1199 // FIXME this completion stuff is a modified clone of
1200 // an OLD version of some stuff in usb.c ...
1201 struct usb_api_data {
1202 	wait_queue_head_t wqh;
1203 	int done;
1204 };
1205 
1206 /*-------------------------------------------------------------------*
1207  * completion handler for compatibility wrappers (sync control/bulk) *
1208  *-------------------------------------------------------------------*/
1209 static void usb_api_blocking_completion(struct urb *urb)
1210 {
1211         struct usb_api_data *awd = (struct usb_api_data *)urb->context;
1212 
1213 	awd->done=1;
1214 	wake_up(&awd->wqh);
1215 }
1216 
1217 /*-------------------------------------------------------------------*
1218  *                         COMPATIBILITY STUFF                       *
1219  *-------------------------------------------------------------------*/
1220 
1221 // Starts urb and waits for completion or timeout
1222 static int usb_start_wait_urb(struct urb *urb, int timeout, int* actual_length)
1223 {
1224 	struct usb_api_data awd;
1225         int status;
1226 
1227         init_waitqueue_head(&awd.wqh);
1228         awd.done = 0;
1229 
1230         urb->context = &awd;
1231         status = usb_submit_urb(urb, GFP_ATOMIC);
1232         if (status) {
1233                 // something went wrong
1234                 usb_free_urb(urb);
1235                 return status;
1236         }
1237 
1238 	if (!wait_event_timeout(awd.wqh, awd.done, timeout)) {
1239                 // timeout
1240                 dev_warn(&urb->dev->dev, "usb_control/bulk_msg: timeout\n");
1241                 usb_kill_urb(urb);  // remove urb safely
1242                 status = -ETIMEDOUT;
1243         }
1244 	else {
1245                 status = urb->status;
1246 	}
1247 
1248         if (actual_length) {
1249                 *actual_length = urb->actual_length;
1250 	}
1251 
1252         usb_free_urb(urb);
1253         return status;
1254 }
1255 
1256 /*-------------------------------------------------------------------*/
1257 // returns status (negative) or length (positive)
1258 static int kaweth_internal_control_msg(struct usb_device *usb_dev,
1259 				       unsigned int pipe,
1260 				       struct usb_ctrlrequest *cmd, void *data,
1261 				       int len, int timeout)
1262 {
1263         struct urb *urb;
1264         int retv;
1265         int length = 0; /* shut up GCC */
1266 
1267 	urb = usb_alloc_urb(0, GFP_ATOMIC);
1268         if (!urb)
1269                 return -ENOMEM;
1270 
1271         usb_fill_control_urb(urb, usb_dev, pipe, (unsigned char*)cmd, data,
1272 			 len, usb_api_blocking_completion, NULL);
1273 
1274         retv = usb_start_wait_urb(urb, timeout, &length);
1275         if (retv < 0) {
1276                 return retv;
1277 	}
1278         else {
1279                 return length;
1280 	}
1281 }
1282 
1283 module_usb_driver(kaweth_driver);
1284