xref: /freebsd/sys/dev/usb/net/if_kue.c (revision fcb560670601b2a4d87bb31d7531c8dcc37ee71b)
1 /*-
2  * Copyright (c) 1997, 1998, 1999, 2000
3  *	Bill Paul <wpaul@ee.columbia.edu>.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by Bill Paul.
16  * 4. Neither the name of the author nor the names of any co-contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR THE VOICES IN HIS HEAD
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
30  * THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 /*
37  * Kawasaki LSI KL5KUSB101B USB to ethernet adapter driver.
38  *
39  * Written by Bill Paul <wpaul@ee.columbia.edu>
40  * Electrical Engineering Department
41  * Columbia University, New York City
42  */
43 
44 /*
45  * The KLSI USB to ethernet adapter chip contains an USB serial interface,
46  * ethernet MAC and embedded microcontroller (called the QT Engine).
47  * The chip must have firmware loaded into it before it will operate.
48  * Packets are passed between the chip and host via bulk transfers.
49  * There is an interrupt endpoint mentioned in the software spec, however
50  * it's currently unused. This device is 10Mbps half-duplex only, hence
51  * there is no media selection logic. The MAC supports a 128 entry
52  * multicast filter, though the exact size of the filter can depend
53  * on the firmware. Curiously, while the software spec describes various
54  * ethernet statistics counters, my sample adapter and firmware combination
55  * claims not to support any statistics counters at all.
56  *
57  * Note that once we load the firmware in the device, we have to be
58  * careful not to load it again: if you restart your computer but
59  * leave the adapter attached to the USB controller, it may remain
60  * powered on and retain its firmware. In this case, we don't need
61  * to load the firmware a second time.
62  *
63  * Special thanks to Rob Furr for providing an ADS Technologies
64  * adapter for development and testing. No monkeys were harmed during
65  * the development of this driver.
66  */
67 
68 #include <sys/stdint.h>
69 #include <sys/stddef.h>
70 #include <sys/param.h>
71 #include <sys/queue.h>
72 #include <sys/types.h>
73 #include <sys/systm.h>
74 #include <sys/socket.h>
75 #include <sys/kernel.h>
76 #include <sys/bus.h>
77 #include <sys/module.h>
78 #include <sys/lock.h>
79 #include <sys/mutex.h>
80 #include <sys/condvar.h>
81 #include <sys/sysctl.h>
82 #include <sys/sx.h>
83 #include <sys/unistd.h>
84 #include <sys/callout.h>
85 #include <sys/malloc.h>
86 #include <sys/priv.h>
87 
88 #include <net/if.h>
89 #include <net/if_var.h>
90 
91 #include <dev/usb/usb.h>
92 #include <dev/usb/usbdi.h>
93 #include <dev/usb/usbdi_util.h>
94 #include "usbdevs.h"
95 
96 #define	USB_DEBUG_VAR kue_debug
97 #include <dev/usb/usb_debug.h>
98 #include <dev/usb/usb_process.h>
99 
100 #include <dev/usb/net/usb_ethernet.h>
101 #include <dev/usb/net/if_kuereg.h>
102 #include <dev/usb/net/if_kuefw.h>
103 
104 /*
105  * Various supported device vendors/products.
106  */
107 static const STRUCT_USB_HOST_ID kue_devs[] = {
108 #define	KUE_DEV(v,p) { USB_VP(USB_VENDOR_##v, USB_PRODUCT_##v##_##p) }
109 	KUE_DEV(3COM, 3C19250),
110 	KUE_DEV(3COM, 3C460),
111 	KUE_DEV(ABOCOM, URE450),
112 	KUE_DEV(ADS, UBS10BT),
113 	KUE_DEV(ADS, UBS10BTX),
114 	KUE_DEV(AOX, USB101),
115 	KUE_DEV(ASANTE, EA),
116 	KUE_DEV(ATEN, DSB650C),
117 	KUE_DEV(ATEN, UC10T),
118 	KUE_DEV(COREGA, ETHER_USB_T),
119 	KUE_DEV(DLINK, DSB650C),
120 	KUE_DEV(ENTREGA, E45),
121 	KUE_DEV(ENTREGA, XX1),
122 	KUE_DEV(ENTREGA, XX2),
123 	KUE_DEV(IODATA, USBETT),
124 	KUE_DEV(JATON, EDA),
125 	KUE_DEV(KINGSTON, XX1),
126 	KUE_DEV(KLSI, DUH3E10BT),
127 	KUE_DEV(KLSI, DUH3E10BTN),
128 	KUE_DEV(LINKSYS, USB10T),
129 	KUE_DEV(MOBILITY, EA),
130 	KUE_DEV(NETGEAR, EA101),
131 	KUE_DEV(NETGEAR, EA101X),
132 	KUE_DEV(PERACOM, ENET),
133 	KUE_DEV(PERACOM, ENET2),
134 	KUE_DEV(PERACOM, ENET3),
135 	KUE_DEV(PORTGEAR, EA8),
136 	KUE_DEV(PORTGEAR, EA9),
137 	KUE_DEV(PORTSMITH, EEA),
138 	KUE_DEV(SHARK, PA),
139 	KUE_DEV(SILICOM, GPE),
140 	KUE_DEV(SILICOM, U2E),
141 	KUE_DEV(SMC, 2102USB),
142 #undef KUE_DEV
143 };
144 
145 /* prototypes */
146 
147 static device_probe_t kue_probe;
148 static device_attach_t kue_attach;
149 static device_detach_t kue_detach;
150 
151 static usb_callback_t kue_bulk_read_callback;
152 static usb_callback_t kue_bulk_write_callback;
153 
154 static uether_fn_t kue_attach_post;
155 static uether_fn_t kue_init;
156 static uether_fn_t kue_stop;
157 static uether_fn_t kue_start;
158 static uether_fn_t kue_setmulti;
159 static uether_fn_t kue_setpromisc;
160 
161 static int	kue_do_request(struct kue_softc *,
162 		    struct usb_device_request *, void *);
163 static int	kue_setword(struct kue_softc *, uint8_t, uint16_t);
164 static int	kue_ctl(struct kue_softc *, uint8_t, uint8_t, uint16_t,
165 		    void *, int);
166 static int	kue_load_fw(struct kue_softc *);
167 static void	kue_reset(struct kue_softc *);
168 
169 #ifdef USB_DEBUG
170 static int kue_debug = 0;
171 
172 static SYSCTL_NODE(_hw_usb, OID_AUTO, kue, CTLFLAG_RW, 0, "USB kue");
173 SYSCTL_INT(_hw_usb_kue, OID_AUTO, debug, CTLFLAG_RWTUN, &kue_debug, 0,
174     "Debug level");
175 #endif
176 
177 static const struct usb_config kue_config[KUE_N_TRANSFER] = {
178 
179 	[KUE_BULK_DT_WR] = {
180 		.type = UE_BULK,
181 		.endpoint = UE_ADDR_ANY,
182 		.direction = UE_DIR_OUT,
183 		.bufsize = (MCLBYTES + 2 + 64),
184 		.flags = {.pipe_bof = 1,},
185 		.callback = kue_bulk_write_callback,
186 		.timeout = 10000,	/* 10 seconds */
187 	},
188 
189 	[KUE_BULK_DT_RD] = {
190 		.type = UE_BULK,
191 		.endpoint = UE_ADDR_ANY,
192 		.direction = UE_DIR_IN,
193 		.bufsize = (MCLBYTES + 2),
194 		.flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
195 		.callback = kue_bulk_read_callback,
196 		.timeout = 0,	/* no timeout */
197 	},
198 };
199 
200 static device_method_t kue_methods[] = {
201 	/* Device interface */
202 	DEVMETHOD(device_probe, kue_probe),
203 	DEVMETHOD(device_attach, kue_attach),
204 	DEVMETHOD(device_detach, kue_detach),
205 
206 	DEVMETHOD_END
207 };
208 
209 static driver_t kue_driver = {
210 	.name = "kue",
211 	.methods = kue_methods,
212 	.size = sizeof(struct kue_softc),
213 };
214 
215 static devclass_t kue_devclass;
216 
217 DRIVER_MODULE(kue, uhub, kue_driver, kue_devclass, NULL, 0);
218 MODULE_DEPEND(kue, uether, 1, 1, 1);
219 MODULE_DEPEND(kue, usb, 1, 1, 1);
220 MODULE_DEPEND(kue, ether, 1, 1, 1);
221 MODULE_VERSION(kue, 1);
222 
223 static const struct usb_ether_methods kue_ue_methods = {
224 	.ue_attach_post = kue_attach_post,
225 	.ue_start = kue_start,
226 	.ue_init = kue_init,
227 	.ue_stop = kue_stop,
228 	.ue_setmulti = kue_setmulti,
229 	.ue_setpromisc = kue_setpromisc,
230 };
231 
232 /*
233  * We have a custom do_request function which is almost like the
234  * regular do_request function, except it has a much longer timeout.
235  * Why? Because we need to make requests over the control endpoint
236  * to download the firmware to the device, which can take longer
237  * than the default timeout.
238  */
239 static int
240 kue_do_request(struct kue_softc *sc, struct usb_device_request *req,
241     void *data)
242 {
243 	usb_error_t err;
244 
245 	err = uether_do_request(&sc->sc_ue, req, data, 60000);
246 
247 	return (err);
248 }
249 
250 static int
251 kue_setword(struct kue_softc *sc, uint8_t breq, uint16_t word)
252 {
253 	struct usb_device_request req;
254 
255 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
256 	req.bRequest = breq;
257 	USETW(req.wValue, word);
258 	USETW(req.wIndex, 0);
259 	USETW(req.wLength, 0);
260 
261 	return (kue_do_request(sc, &req, NULL));
262 }
263 
264 static int
265 kue_ctl(struct kue_softc *sc, uint8_t rw, uint8_t breq,
266     uint16_t val, void *data, int len)
267 {
268 	struct usb_device_request req;
269 
270 	if (rw == KUE_CTL_WRITE)
271 		req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
272 	else
273 		req.bmRequestType = UT_READ_VENDOR_DEVICE;
274 
275 
276 	req.bRequest = breq;
277 	USETW(req.wValue, val);
278 	USETW(req.wIndex, 0);
279 	USETW(req.wLength, len);
280 
281 	return (kue_do_request(sc, &req, data));
282 }
283 
284 static int
285 kue_load_fw(struct kue_softc *sc)
286 {
287 	struct usb_device_descriptor *dd;
288 	uint16_t hwrev;
289 	usb_error_t err;
290 
291 	dd = usbd_get_device_descriptor(sc->sc_ue.ue_udev);
292 	hwrev = UGETW(dd->bcdDevice);
293 
294 	/*
295 	 * First, check if we even need to load the firmware.
296 	 * If the device was still attached when the system was
297 	 * rebooted, it may already have firmware loaded in it.
298 	 * If this is the case, we don't need to do it again.
299 	 * And in fact, if we try to load it again, we'll hang,
300 	 * so we have to avoid this condition if we don't want
301 	 * to look stupid.
302 	 *
303 	 * We can test this quickly by checking the bcdRevision
304 	 * code. The NIC will return a different revision code if
305 	 * it's probed while the firmware is still loaded and
306 	 * running.
307 	 */
308 	if (hwrev == 0x0202)
309 		return(0);
310 
311 	/* Load code segment */
312 	err = kue_ctl(sc, KUE_CTL_WRITE, KUE_CMD_SEND_SCAN,
313 	    0, kue_code_seg, sizeof(kue_code_seg));
314 	if (err) {
315 		device_printf(sc->sc_ue.ue_dev, "failed to load code segment: %s\n",
316 		    usbd_errstr(err));
317 		return(ENXIO);
318 	}
319 
320 	/* Load fixup segment */
321 	err = kue_ctl(sc, KUE_CTL_WRITE, KUE_CMD_SEND_SCAN,
322 	    0, kue_fix_seg, sizeof(kue_fix_seg));
323 	if (err) {
324 		device_printf(sc->sc_ue.ue_dev, "failed to load fixup segment: %s\n",
325 		    usbd_errstr(err));
326 		return(ENXIO);
327 	}
328 
329 	/* Send trigger command. */
330 	err = kue_ctl(sc, KUE_CTL_WRITE, KUE_CMD_SEND_SCAN,
331 	    0, kue_trig_seg, sizeof(kue_trig_seg));
332 	if (err) {
333 		device_printf(sc->sc_ue.ue_dev, "failed to load trigger segment: %s\n",
334 		    usbd_errstr(err));
335 		return(ENXIO);
336 	}
337 
338 	return (0);
339 }
340 
341 static void
342 kue_setpromisc(struct usb_ether *ue)
343 {
344 	struct kue_softc *sc = uether_getsc(ue);
345 	struct ifnet *ifp = uether_getifp(ue);
346 
347 	KUE_LOCK_ASSERT(sc, MA_OWNED);
348 
349 	if (ifp->if_flags & IFF_PROMISC)
350 		sc->sc_rxfilt |= KUE_RXFILT_PROMISC;
351 	else
352 		sc->sc_rxfilt &= ~KUE_RXFILT_PROMISC;
353 
354 	kue_setword(sc, KUE_CMD_SET_PKT_FILTER, sc->sc_rxfilt);
355 }
356 
357 static void
358 kue_setmulti(struct usb_ether *ue)
359 {
360 	struct kue_softc *sc = uether_getsc(ue);
361 	struct ifnet *ifp = uether_getifp(ue);
362 	struct ifmultiaddr *ifma;
363 	int i = 0;
364 
365 	KUE_LOCK_ASSERT(sc, MA_OWNED);
366 
367 	if (ifp->if_flags & IFF_ALLMULTI || ifp->if_flags & IFF_PROMISC) {
368 		sc->sc_rxfilt |= KUE_RXFILT_ALLMULTI;
369 		sc->sc_rxfilt &= ~KUE_RXFILT_MULTICAST;
370 		kue_setword(sc, KUE_CMD_SET_PKT_FILTER, sc->sc_rxfilt);
371 		return;
372 	}
373 
374 	sc->sc_rxfilt &= ~KUE_RXFILT_ALLMULTI;
375 
376 	if_maddr_rlock(ifp);
377 	TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link)
378 	{
379 		if (ifma->ifma_addr->sa_family != AF_LINK)
380 			continue;
381 		/*
382 		 * If there are too many addresses for the
383 		 * internal filter, switch over to allmulti mode.
384 		 */
385 		if (i == KUE_MCFILTCNT(sc))
386 			break;
387 		memcpy(KUE_MCFILT(sc, i),
388 		    LLADDR((struct sockaddr_dl *)ifma->ifma_addr),
389 		    ETHER_ADDR_LEN);
390 		i++;
391 	}
392 	if_maddr_runlock(ifp);
393 
394 	if (i == KUE_MCFILTCNT(sc))
395 		sc->sc_rxfilt |= KUE_RXFILT_ALLMULTI;
396 	else {
397 		sc->sc_rxfilt |= KUE_RXFILT_MULTICAST;
398 		kue_ctl(sc, KUE_CTL_WRITE, KUE_CMD_SET_MCAST_FILTERS,
399 		    i, sc->sc_mcfilters, i * ETHER_ADDR_LEN);
400 	}
401 
402 	kue_setword(sc, KUE_CMD_SET_PKT_FILTER, sc->sc_rxfilt);
403 }
404 
405 /*
406  * Issue a SET_CONFIGURATION command to reset the MAC. This should be
407  * done after the firmware is loaded into the adapter in order to
408  * bring it into proper operation.
409  */
410 static void
411 kue_reset(struct kue_softc *sc)
412 {
413 	struct usb_config_descriptor *cd;
414 	usb_error_t err;
415 
416 	cd = usbd_get_config_descriptor(sc->sc_ue.ue_udev);
417 
418 	err = usbd_req_set_config(sc->sc_ue.ue_udev, &sc->sc_mtx,
419 	    cd->bConfigurationValue);
420 	if (err)
421 		DPRINTF("reset failed (ignored)\n");
422 
423 	/* wait a little while for the chip to get its brains in order */
424 	uether_pause(&sc->sc_ue, hz / 100);
425 }
426 
427 static void
428 kue_attach_post(struct usb_ether *ue)
429 {
430 	struct kue_softc *sc = uether_getsc(ue);
431 	int error;
432 
433 	/* load the firmware into the NIC */
434 	error = kue_load_fw(sc);
435 	if (error) {
436 		device_printf(sc->sc_ue.ue_dev, "could not load firmware\n");
437 		/* ignore the error */
438 	}
439 
440 	/* reset the adapter */
441 	kue_reset(sc);
442 
443 	/* read ethernet descriptor */
444 	kue_ctl(sc, KUE_CTL_READ, KUE_CMD_GET_ETHER_DESCRIPTOR,
445 	    0, &sc->sc_desc, sizeof(sc->sc_desc));
446 
447 	/* copy in ethernet address */
448 	memcpy(ue->ue_eaddr, sc->sc_desc.kue_macaddr, sizeof(ue->ue_eaddr));
449 }
450 
451 /*
452  * Probe for a KLSI chip.
453  */
454 static int
455 kue_probe(device_t dev)
456 {
457 	struct usb_attach_arg *uaa = device_get_ivars(dev);
458 
459 	if (uaa->usb_mode != USB_MODE_HOST)
460 		return (ENXIO);
461 	if (uaa->info.bConfigIndex != KUE_CONFIG_IDX)
462 		return (ENXIO);
463 	if (uaa->info.bIfaceIndex != KUE_IFACE_IDX)
464 		return (ENXIO);
465 
466 	return (usbd_lookup_id_by_uaa(kue_devs, sizeof(kue_devs), uaa));
467 }
468 
469 /*
470  * Attach the interface. Allocate softc structures, do
471  * setup and ethernet/BPF attach.
472  */
473 static int
474 kue_attach(device_t dev)
475 {
476 	struct usb_attach_arg *uaa = device_get_ivars(dev);
477 	struct kue_softc *sc = device_get_softc(dev);
478 	struct usb_ether *ue = &sc->sc_ue;
479 	uint8_t iface_index;
480 	int error;
481 
482 	device_set_usb_desc(dev);
483 	mtx_init(&sc->sc_mtx, device_get_nameunit(dev), NULL, MTX_DEF);
484 
485 	iface_index = KUE_IFACE_IDX;
486 	error = usbd_transfer_setup(uaa->device, &iface_index,
487 	    sc->sc_xfer, kue_config, KUE_N_TRANSFER, sc, &sc->sc_mtx);
488 	if (error) {
489 		device_printf(dev, "allocating USB transfers failed\n");
490 		goto detach;
491 	}
492 
493 	sc->sc_mcfilters = malloc(KUE_MCFILTCNT(sc) * ETHER_ADDR_LEN,
494 	    M_USBDEV, M_WAITOK);
495 	if (sc->sc_mcfilters == NULL) {
496 		device_printf(dev, "failed allocating USB memory\n");
497 		goto detach;
498 	}
499 
500 	ue->ue_sc = sc;
501 	ue->ue_dev = dev;
502 	ue->ue_udev = uaa->device;
503 	ue->ue_mtx = &sc->sc_mtx;
504 	ue->ue_methods = &kue_ue_methods;
505 
506 	error = uether_ifattach(ue);
507 	if (error) {
508 		device_printf(dev, "could not attach interface\n");
509 		goto detach;
510 	}
511 	return (0);			/* success */
512 
513 detach:
514 	kue_detach(dev);
515 	return (ENXIO);			/* failure */
516 }
517 
518 static int
519 kue_detach(device_t dev)
520 {
521 	struct kue_softc *sc = device_get_softc(dev);
522 	struct usb_ether *ue = &sc->sc_ue;
523 
524 	usbd_transfer_unsetup(sc->sc_xfer, KUE_N_TRANSFER);
525 	uether_ifdetach(ue);
526 	mtx_destroy(&sc->sc_mtx);
527 	free(sc->sc_mcfilters, M_USBDEV);
528 
529 	return (0);
530 }
531 
532 /*
533  * A frame has been uploaded: pass the resulting mbuf chain up to
534  * the higher level protocols.
535  */
536 static void
537 kue_bulk_read_callback(struct usb_xfer *xfer, usb_error_t error)
538 {
539 	struct kue_softc *sc = usbd_xfer_softc(xfer);
540 	struct usb_ether *ue = &sc->sc_ue;
541 	struct ifnet *ifp = uether_getifp(ue);
542 	struct usb_page_cache *pc;
543 	uint8_t buf[2];
544 	int len;
545 	int actlen;
546 
547 	usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
548 
549 	switch (USB_GET_STATE(xfer)) {
550 	case USB_ST_TRANSFERRED:
551 
552 		if (actlen <= (int)(2 + sizeof(struct ether_header))) {
553 			if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
554 			goto tr_setup;
555 		}
556 		pc = usbd_xfer_get_frame(xfer, 0);
557 		usbd_copy_out(pc, 0, buf, 2);
558 		actlen -= 2;
559 		len = buf[0] | (buf[1] << 8);
560 		len = min(actlen, len);
561 
562 		uether_rxbuf(ue, pc, 2, len);
563 		/* FALLTHROUGH */
564 	case USB_ST_SETUP:
565 tr_setup:
566 		usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
567 		usbd_transfer_submit(xfer);
568 		uether_rxflush(ue);
569 		return;
570 
571 	default:			/* Error */
572 		DPRINTF("bulk read error, %s\n",
573 		    usbd_errstr(error));
574 
575 		if (error != USB_ERR_CANCELLED) {
576 			/* try to clear stall first */
577 			usbd_xfer_set_stall(xfer);
578 			goto tr_setup;
579 		}
580 		return;
581 
582 	}
583 }
584 
585 static void
586 kue_bulk_write_callback(struct usb_xfer *xfer, usb_error_t error)
587 {
588 	struct kue_softc *sc = usbd_xfer_softc(xfer);
589 	struct ifnet *ifp = uether_getifp(&sc->sc_ue);
590 	struct usb_page_cache *pc;
591 	struct mbuf *m;
592 	int total_len;
593 	int temp_len;
594 	uint8_t buf[2];
595 
596 	switch (USB_GET_STATE(xfer)) {
597 	case USB_ST_TRANSFERRED:
598 		DPRINTFN(11, "transfer complete\n");
599 		if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
600 
601 		/* FALLTHROUGH */
602 	case USB_ST_SETUP:
603 tr_setup:
604 		IFQ_DRV_DEQUEUE(&ifp->if_snd, m);
605 
606 		if (m == NULL)
607 			return;
608 		if (m->m_pkthdr.len > MCLBYTES)
609 			m->m_pkthdr.len = MCLBYTES;
610 		temp_len = (m->m_pkthdr.len + 2);
611 		total_len = (temp_len + (64 - (temp_len % 64)));
612 
613 		/* the first two bytes are the frame length */
614 
615 		buf[0] = (uint8_t)(m->m_pkthdr.len);
616 		buf[1] = (uint8_t)(m->m_pkthdr.len >> 8);
617 
618 		pc = usbd_xfer_get_frame(xfer, 0);
619 		usbd_copy_in(pc, 0, buf, 2);
620 		usbd_m_copy_in(pc, 2, m, 0, m->m_pkthdr.len);
621 
622 		usbd_frame_zero(pc, temp_len, total_len - temp_len);
623 		usbd_xfer_set_frame_len(xfer, 0, total_len);
624 
625 		/*
626 		 * if there's a BPF listener, bounce a copy
627 		 * of this frame to him:
628 		 */
629 		BPF_MTAP(ifp, m);
630 
631 		m_freem(m);
632 
633 		usbd_transfer_submit(xfer);
634 
635 		return;
636 
637 	default:			/* Error */
638 		DPRINTFN(11, "transfer error, %s\n",
639 		    usbd_errstr(error));
640 
641 		if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
642 
643 		if (error != USB_ERR_CANCELLED) {
644 			/* try to clear stall first */
645 			usbd_xfer_set_stall(xfer);
646 			goto tr_setup;
647 		}
648 		return;
649 
650 	}
651 }
652 
653 static void
654 kue_start(struct usb_ether *ue)
655 {
656 	struct kue_softc *sc = uether_getsc(ue);
657 
658 	/*
659 	 * start the USB transfers, if not already started:
660 	 */
661 	usbd_transfer_start(sc->sc_xfer[KUE_BULK_DT_RD]);
662 	usbd_transfer_start(sc->sc_xfer[KUE_BULK_DT_WR]);
663 }
664 
665 static void
666 kue_init(struct usb_ether *ue)
667 {
668 	struct kue_softc *sc = uether_getsc(ue);
669 	struct ifnet *ifp = uether_getifp(ue);
670 
671 	KUE_LOCK_ASSERT(sc, MA_OWNED);
672 
673 	/* set MAC address */
674 	kue_ctl(sc, KUE_CTL_WRITE, KUE_CMD_SET_MAC,
675 	    0, IF_LLADDR(ifp), ETHER_ADDR_LEN);
676 
677 	/* I'm not sure how to tune these. */
678 #if 0
679 	/*
680 	 * Leave this one alone for now; setting it
681 	 * wrong causes lockups on some machines/controllers.
682 	 */
683 	kue_setword(sc, KUE_CMD_SET_SOFS, 1);
684 #endif
685 	kue_setword(sc, KUE_CMD_SET_URB_SIZE, 64);
686 
687 	/* load the multicast filter */
688 	kue_setpromisc(ue);
689 
690 	usbd_xfer_set_stall(sc->sc_xfer[KUE_BULK_DT_WR]);
691 
692 	ifp->if_drv_flags |= IFF_DRV_RUNNING;
693 	kue_start(ue);
694 }
695 
696 static void
697 kue_stop(struct usb_ether *ue)
698 {
699 	struct kue_softc *sc = uether_getsc(ue);
700 	struct ifnet *ifp = uether_getifp(ue);
701 
702 	KUE_LOCK_ASSERT(sc, MA_OWNED);
703 
704 	ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
705 
706 	/*
707 	 * stop all the transfers, if not already stopped:
708 	 */
709 	usbd_transfer_stop(sc->sc_xfer[KUE_BULK_DT_WR]);
710 	usbd_transfer_stop(sc->sc_xfer[KUE_BULK_DT_RD]);
711 }
712