xref: /freebsd/sys/dev/usb/net/if_kue.c (revision 994297b01b98816bea1abf45ae4bac1bc69ee7a0)
1 /*-
2  * SPDX-License-Identifier: BSD-4-Clause
3  *
4  * Copyright (c) 1997, 1998, 1999, 2000
5  *	Bill Paul <wpaul@ee.columbia.edu>.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by Bill Paul.
18  * 4. Neither the name of the author nor the names of any co-contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR THE VOICES IN HIS HEAD
26  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
31  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
32  * THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 /*
39  * Kawasaki LSI KL5KUSB101B USB to ethernet adapter driver.
40  *
41  * Written by Bill Paul <wpaul@ee.columbia.edu>
42  * Electrical Engineering Department
43  * Columbia University, New York City
44  */
45 
46 /*
47  * The KLSI USB to ethernet adapter chip contains an USB serial interface,
48  * ethernet MAC and embedded microcontroller (called the QT Engine).
49  * The chip must have firmware loaded into it before it will operate.
50  * Packets are passed between the chip and host via bulk transfers.
51  * There is an interrupt endpoint mentioned in the software spec, however
52  * it's currently unused. This device is 10Mbps half-duplex only, hence
53  * there is no media selection logic. The MAC supports a 128 entry
54  * multicast filter, though the exact size of the filter can depend
55  * on the firmware. Curiously, while the software spec describes various
56  * ethernet statistics counters, my sample adapter and firmware combination
57  * claims not to support any statistics counters at all.
58  *
59  * Note that once we load the firmware in the device, we have to be
60  * careful not to load it again: if you restart your computer but
61  * leave the adapter attached to the USB controller, it may remain
62  * powered on and retain its firmware. In this case, we don't need
63  * to load the firmware a second time.
64  *
65  * Special thanks to Rob Furr for providing an ADS Technologies
66  * adapter for development and testing. No monkeys were harmed during
67  * the development of this driver.
68  */
69 
70 #include <sys/stdint.h>
71 #include <sys/stddef.h>
72 #include <sys/param.h>
73 #include <sys/queue.h>
74 #include <sys/types.h>
75 #include <sys/systm.h>
76 #include <sys/socket.h>
77 #include <sys/kernel.h>
78 #include <sys/bus.h>
79 #include <sys/module.h>
80 #include <sys/lock.h>
81 #include <sys/mutex.h>
82 #include <sys/condvar.h>
83 #include <sys/sysctl.h>
84 #include <sys/sx.h>
85 #include <sys/unistd.h>
86 #include <sys/callout.h>
87 #include <sys/malloc.h>
88 #include <sys/priv.h>
89 
90 #include <net/if.h>
91 #include <net/if_var.h>
92 
93 #include <dev/usb/usb.h>
94 #include <dev/usb/usbdi.h>
95 #include <dev/usb/usbdi_util.h>
96 #include "usbdevs.h"
97 
98 #define	USB_DEBUG_VAR kue_debug
99 #include <dev/usb/usb_debug.h>
100 #include <dev/usb/usb_process.h>
101 
102 #include <dev/usb/net/usb_ethernet.h>
103 #include <dev/usb/net/if_kuereg.h>
104 #include <dev/usb/net/if_kuefw.h>
105 
106 /*
107  * Various supported device vendors/products.
108  */
109 static const STRUCT_USB_HOST_ID kue_devs[] = {
110 #define	KUE_DEV(v,p) { USB_VP(USB_VENDOR_##v, USB_PRODUCT_##v##_##p) }
111 	KUE_DEV(3COM, 3C19250),
112 	KUE_DEV(3COM, 3C460),
113 	KUE_DEV(ABOCOM, URE450),
114 	KUE_DEV(ADS, UBS10BT),
115 	KUE_DEV(ADS, UBS10BTX),
116 	KUE_DEV(AOX, USB101),
117 	KUE_DEV(ASANTE, EA),
118 	KUE_DEV(ATEN, DSB650C),
119 	KUE_DEV(ATEN, UC10T),
120 	KUE_DEV(COREGA, ETHER_USB_T),
121 	KUE_DEV(DLINK, DSB650C),
122 	KUE_DEV(ENTREGA, E45),
123 	KUE_DEV(ENTREGA, XX1),
124 	KUE_DEV(ENTREGA, XX2),
125 	KUE_DEV(IODATA, USBETT),
126 	KUE_DEV(JATON, EDA),
127 	KUE_DEV(KINGSTON, XX1),
128 	KUE_DEV(KLSI, DUH3E10BT),
129 	KUE_DEV(KLSI, DUH3E10BTN),
130 	KUE_DEV(LINKSYS, USB10T),
131 	KUE_DEV(MOBILITY, EA),
132 	KUE_DEV(NETGEAR, EA101),
133 	KUE_DEV(NETGEAR, EA101X),
134 	KUE_DEV(PERACOM, ENET),
135 	KUE_DEV(PERACOM, ENET2),
136 	KUE_DEV(PERACOM, ENET3),
137 	KUE_DEV(PORTGEAR, EA8),
138 	KUE_DEV(PORTGEAR, EA9),
139 	KUE_DEV(PORTSMITH, EEA),
140 	KUE_DEV(SHARK, PA),
141 	KUE_DEV(SILICOM, GPE),
142 	KUE_DEV(SILICOM, U2E),
143 	KUE_DEV(SMC, 2102USB),
144 #undef KUE_DEV
145 };
146 
147 /* prototypes */
148 
149 static device_probe_t kue_probe;
150 static device_attach_t kue_attach;
151 static device_detach_t kue_detach;
152 
153 static usb_callback_t kue_bulk_read_callback;
154 static usb_callback_t kue_bulk_write_callback;
155 
156 static uether_fn_t kue_attach_post;
157 static uether_fn_t kue_init;
158 static uether_fn_t kue_stop;
159 static uether_fn_t kue_start;
160 static uether_fn_t kue_setmulti;
161 static uether_fn_t kue_setpromisc;
162 
163 static int	kue_do_request(struct kue_softc *,
164 		    struct usb_device_request *, void *);
165 static int	kue_setword(struct kue_softc *, uint8_t, uint16_t);
166 static int	kue_ctl(struct kue_softc *, uint8_t, uint8_t, uint16_t,
167 		    void *, int);
168 static int	kue_load_fw(struct kue_softc *);
169 static void	kue_reset(struct kue_softc *);
170 
171 #ifdef USB_DEBUG
172 static int kue_debug = 0;
173 
174 static SYSCTL_NODE(_hw_usb, OID_AUTO, kue, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
175     "USB kue");
176 SYSCTL_INT(_hw_usb_kue, OID_AUTO, debug, CTLFLAG_RWTUN, &kue_debug, 0,
177     "Debug level");
178 #endif
179 
180 static const struct usb_config kue_config[KUE_N_TRANSFER] = {
181 	[KUE_BULK_DT_WR] = {
182 		.type = UE_BULK,
183 		.endpoint = UE_ADDR_ANY,
184 		.direction = UE_DIR_OUT,
185 		.bufsize = (MCLBYTES + 2 + 64),
186 		.flags = {.pipe_bof = 1,},
187 		.callback = kue_bulk_write_callback,
188 		.timeout = 10000,	/* 10 seconds */
189 	},
190 
191 	[KUE_BULK_DT_RD] = {
192 		.type = UE_BULK,
193 		.endpoint = UE_ADDR_ANY,
194 		.direction = UE_DIR_IN,
195 		.bufsize = (MCLBYTES + 2),
196 		.flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
197 		.callback = kue_bulk_read_callback,
198 		.timeout = 0,	/* no timeout */
199 	},
200 };
201 
202 static device_method_t kue_methods[] = {
203 	/* Device interface */
204 	DEVMETHOD(device_probe, kue_probe),
205 	DEVMETHOD(device_attach, kue_attach),
206 	DEVMETHOD(device_detach, kue_detach),
207 
208 	DEVMETHOD_END
209 };
210 
211 static driver_t kue_driver = {
212 	.name = "kue",
213 	.methods = kue_methods,
214 	.size = sizeof(struct kue_softc),
215 };
216 
217 static devclass_t kue_devclass;
218 
219 DRIVER_MODULE(kue, uhub, kue_driver, kue_devclass, NULL, 0);
220 MODULE_DEPEND(kue, uether, 1, 1, 1);
221 MODULE_DEPEND(kue, usb, 1, 1, 1);
222 MODULE_DEPEND(kue, ether, 1, 1, 1);
223 MODULE_VERSION(kue, 1);
224 USB_PNP_HOST_INFO(kue_devs);
225 
226 static const struct usb_ether_methods kue_ue_methods = {
227 	.ue_attach_post = kue_attach_post,
228 	.ue_start = kue_start,
229 	.ue_init = kue_init,
230 	.ue_stop = kue_stop,
231 	.ue_setmulti = kue_setmulti,
232 	.ue_setpromisc = kue_setpromisc,
233 };
234 
235 /*
236  * We have a custom do_request function which is almost like the
237  * regular do_request function, except it has a much longer timeout.
238  * Why? Because we need to make requests over the control endpoint
239  * to download the firmware to the device, which can take longer
240  * than the default timeout.
241  */
242 static int
243 kue_do_request(struct kue_softc *sc, struct usb_device_request *req,
244     void *data)
245 {
246 	usb_error_t err;
247 
248 	err = uether_do_request(&sc->sc_ue, req, data, 60000);
249 
250 	return (err);
251 }
252 
253 static int
254 kue_setword(struct kue_softc *sc, uint8_t breq, uint16_t word)
255 {
256 	struct usb_device_request req;
257 
258 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
259 	req.bRequest = breq;
260 	USETW(req.wValue, word);
261 	USETW(req.wIndex, 0);
262 	USETW(req.wLength, 0);
263 
264 	return (kue_do_request(sc, &req, NULL));
265 }
266 
267 static int
268 kue_ctl(struct kue_softc *sc, uint8_t rw, uint8_t breq,
269     uint16_t val, void *data, int len)
270 {
271 	struct usb_device_request req;
272 
273 	if (rw == KUE_CTL_WRITE)
274 		req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
275 	else
276 		req.bmRequestType = UT_READ_VENDOR_DEVICE;
277 
278 	req.bRequest = breq;
279 	USETW(req.wValue, val);
280 	USETW(req.wIndex, 0);
281 	USETW(req.wLength, len);
282 
283 	return (kue_do_request(sc, &req, data));
284 }
285 
286 static int
287 kue_load_fw(struct kue_softc *sc)
288 {
289 	struct usb_device_descriptor *dd;
290 	uint16_t hwrev;
291 	usb_error_t err;
292 
293 	dd = usbd_get_device_descriptor(sc->sc_ue.ue_udev);
294 	hwrev = UGETW(dd->bcdDevice);
295 
296 	/*
297 	 * First, check if we even need to load the firmware.
298 	 * If the device was still attached when the system was
299 	 * rebooted, it may already have firmware loaded in it.
300 	 * If this is the case, we don't need to do it again.
301 	 * And in fact, if we try to load it again, we'll hang,
302 	 * so we have to avoid this condition if we don't want
303 	 * to look stupid.
304 	 *
305 	 * We can test this quickly by checking the bcdRevision
306 	 * code. The NIC will return a different revision code if
307 	 * it's probed while the firmware is still loaded and
308 	 * running.
309 	 */
310 	if (hwrev == 0x0202)
311 		return(0);
312 
313 	/* Load code segment */
314 	err = kue_ctl(sc, KUE_CTL_WRITE, KUE_CMD_SEND_SCAN,
315 	    0, kue_code_seg, sizeof(kue_code_seg));
316 	if (err) {
317 		device_printf(sc->sc_ue.ue_dev, "failed to load code segment: %s\n",
318 		    usbd_errstr(err));
319 		return(ENXIO);
320 	}
321 
322 	/* Load fixup segment */
323 	err = kue_ctl(sc, KUE_CTL_WRITE, KUE_CMD_SEND_SCAN,
324 	    0, kue_fix_seg, sizeof(kue_fix_seg));
325 	if (err) {
326 		device_printf(sc->sc_ue.ue_dev, "failed to load fixup segment: %s\n",
327 		    usbd_errstr(err));
328 		return(ENXIO);
329 	}
330 
331 	/* Send trigger command. */
332 	err = kue_ctl(sc, KUE_CTL_WRITE, KUE_CMD_SEND_SCAN,
333 	    0, kue_trig_seg, sizeof(kue_trig_seg));
334 	if (err) {
335 		device_printf(sc->sc_ue.ue_dev, "failed to load trigger segment: %s\n",
336 		    usbd_errstr(err));
337 		return(ENXIO);
338 	}
339 
340 	return (0);
341 }
342 
343 static void
344 kue_setpromisc(struct usb_ether *ue)
345 {
346 	struct kue_softc *sc = uether_getsc(ue);
347 	struct ifnet *ifp = uether_getifp(ue);
348 
349 	KUE_LOCK_ASSERT(sc, MA_OWNED);
350 
351 	if (ifp->if_flags & IFF_PROMISC)
352 		sc->sc_rxfilt |= KUE_RXFILT_PROMISC;
353 	else
354 		sc->sc_rxfilt &= ~KUE_RXFILT_PROMISC;
355 
356 	kue_setword(sc, KUE_CMD_SET_PKT_FILTER, sc->sc_rxfilt);
357 }
358 
359 static u_int
360 kue_copy_maddr(void *arg, struct sockaddr_dl *sdl, u_int cnt)
361 {
362 	struct kue_softc *sc = arg;
363 
364 	if (cnt >= KUE_MCFILTCNT(sc))
365 		return (1);
366 
367 	memcpy(KUE_MCFILT(sc, cnt), LLADDR(sdl), ETHER_ADDR_LEN);
368 
369 	return (1);
370 }
371 
372 static void
373 kue_setmulti(struct usb_ether *ue)
374 {
375 	struct kue_softc *sc = uether_getsc(ue);
376 	struct ifnet *ifp = uether_getifp(ue);
377 	int i;
378 
379 	KUE_LOCK_ASSERT(sc, MA_OWNED);
380 
381 	if (ifp->if_flags & IFF_ALLMULTI || ifp->if_flags & IFF_PROMISC) {
382 		sc->sc_rxfilt |= KUE_RXFILT_ALLMULTI;
383 		sc->sc_rxfilt &= ~KUE_RXFILT_MULTICAST;
384 		kue_setword(sc, KUE_CMD_SET_PKT_FILTER, sc->sc_rxfilt);
385 		return;
386 	}
387 
388 	sc->sc_rxfilt &= ~KUE_RXFILT_ALLMULTI;
389 
390 	i = if_foreach_llmaddr(ifp, kue_copy_maddr, sc);
391 
392 	if (i >= KUE_MCFILTCNT(sc))
393 		sc->sc_rxfilt |= KUE_RXFILT_ALLMULTI;
394 	else {
395 		sc->sc_rxfilt |= KUE_RXFILT_MULTICAST;
396 		kue_ctl(sc, KUE_CTL_WRITE, KUE_CMD_SET_MCAST_FILTERS,
397 		    i, sc->sc_mcfilters, i * ETHER_ADDR_LEN);
398 	}
399 
400 	kue_setword(sc, KUE_CMD_SET_PKT_FILTER, sc->sc_rxfilt);
401 }
402 
403 /*
404  * Issue a SET_CONFIGURATION command to reset the MAC. This should be
405  * done after the firmware is loaded into the adapter in order to
406  * bring it into proper operation.
407  */
408 static void
409 kue_reset(struct kue_softc *sc)
410 {
411 	struct usb_config_descriptor *cd;
412 	usb_error_t err;
413 
414 	cd = usbd_get_config_descriptor(sc->sc_ue.ue_udev);
415 
416 	err = usbd_req_set_config(sc->sc_ue.ue_udev, &sc->sc_mtx,
417 	    cd->bConfigurationValue);
418 	if (err)
419 		DPRINTF("reset failed (ignored)\n");
420 
421 	/* wait a little while for the chip to get its brains in order */
422 	uether_pause(&sc->sc_ue, hz / 100);
423 }
424 
425 static void
426 kue_attach_post(struct usb_ether *ue)
427 {
428 	struct kue_softc *sc = uether_getsc(ue);
429 	int error;
430 
431 	/* load the firmware into the NIC */
432 	error = kue_load_fw(sc);
433 	if (error) {
434 		device_printf(sc->sc_ue.ue_dev, "could not load firmware\n");
435 		/* ignore the error */
436 	}
437 
438 	/* reset the adapter */
439 	kue_reset(sc);
440 
441 	/* read ethernet descriptor */
442 	kue_ctl(sc, KUE_CTL_READ, KUE_CMD_GET_ETHER_DESCRIPTOR,
443 	    0, &sc->sc_desc, sizeof(sc->sc_desc));
444 
445 	/* copy in ethernet address */
446 	memcpy(ue->ue_eaddr, sc->sc_desc.kue_macaddr, sizeof(ue->ue_eaddr));
447 }
448 
449 /*
450  * Probe for a KLSI chip.
451  */
452 static int
453 kue_probe(device_t dev)
454 {
455 	struct usb_attach_arg *uaa = device_get_ivars(dev);
456 
457 	if (uaa->usb_mode != USB_MODE_HOST)
458 		return (ENXIO);
459 	if (uaa->info.bConfigIndex != KUE_CONFIG_IDX)
460 		return (ENXIO);
461 	if (uaa->info.bIfaceIndex != KUE_IFACE_IDX)
462 		return (ENXIO);
463 
464 	return (usbd_lookup_id_by_uaa(kue_devs, sizeof(kue_devs), uaa));
465 }
466 
467 /*
468  * Attach the interface. Allocate softc structures, do
469  * setup and ethernet/BPF attach.
470  */
471 static int
472 kue_attach(device_t dev)
473 {
474 	struct usb_attach_arg *uaa = device_get_ivars(dev);
475 	struct kue_softc *sc = device_get_softc(dev);
476 	struct usb_ether *ue = &sc->sc_ue;
477 	uint8_t iface_index;
478 	int error;
479 
480 	device_set_usb_desc(dev);
481 	mtx_init(&sc->sc_mtx, device_get_nameunit(dev), NULL, MTX_DEF);
482 
483 	iface_index = KUE_IFACE_IDX;
484 	error = usbd_transfer_setup(uaa->device, &iface_index,
485 	    sc->sc_xfer, kue_config, KUE_N_TRANSFER, sc, &sc->sc_mtx);
486 	if (error) {
487 		device_printf(dev, "allocating USB transfers failed\n");
488 		goto detach;
489 	}
490 
491 	sc->sc_mcfilters = malloc(KUE_MCFILTCNT(sc) * ETHER_ADDR_LEN,
492 	    M_USBDEV, M_WAITOK);
493 	if (sc->sc_mcfilters == NULL) {
494 		device_printf(dev, "failed allocating USB memory\n");
495 		goto detach;
496 	}
497 
498 	ue->ue_sc = sc;
499 	ue->ue_dev = dev;
500 	ue->ue_udev = uaa->device;
501 	ue->ue_mtx = &sc->sc_mtx;
502 	ue->ue_methods = &kue_ue_methods;
503 
504 	error = uether_ifattach(ue);
505 	if (error) {
506 		device_printf(dev, "could not attach interface\n");
507 		goto detach;
508 	}
509 	return (0);			/* success */
510 
511 detach:
512 	kue_detach(dev);
513 	return (ENXIO);			/* failure */
514 }
515 
516 static int
517 kue_detach(device_t dev)
518 {
519 	struct kue_softc *sc = device_get_softc(dev);
520 	struct usb_ether *ue = &sc->sc_ue;
521 
522 	usbd_transfer_unsetup(sc->sc_xfer, KUE_N_TRANSFER);
523 	uether_ifdetach(ue);
524 	mtx_destroy(&sc->sc_mtx);
525 	free(sc->sc_mcfilters, M_USBDEV);
526 
527 	return (0);
528 }
529 
530 /*
531  * A frame has been uploaded: pass the resulting mbuf chain up to
532  * the higher level protocols.
533  */
534 static void
535 kue_bulk_read_callback(struct usb_xfer *xfer, usb_error_t error)
536 {
537 	struct kue_softc *sc = usbd_xfer_softc(xfer);
538 	struct usb_ether *ue = &sc->sc_ue;
539 	struct ifnet *ifp = uether_getifp(ue);
540 	struct usb_page_cache *pc;
541 	uint8_t buf[2];
542 	int len;
543 	int actlen;
544 
545 	usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
546 
547 	switch (USB_GET_STATE(xfer)) {
548 	case USB_ST_TRANSFERRED:
549 
550 		if (actlen <= (int)(2 + sizeof(struct ether_header))) {
551 			if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
552 			goto tr_setup;
553 		}
554 		pc = usbd_xfer_get_frame(xfer, 0);
555 		usbd_copy_out(pc, 0, buf, 2);
556 		actlen -= 2;
557 		len = buf[0] | (buf[1] << 8);
558 		len = min(actlen, len);
559 
560 		uether_rxbuf(ue, pc, 2, len);
561 		/* FALLTHROUGH */
562 	case USB_ST_SETUP:
563 tr_setup:
564 		usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
565 		usbd_transfer_submit(xfer);
566 		uether_rxflush(ue);
567 		return;
568 
569 	default:			/* Error */
570 		DPRINTF("bulk read error, %s\n",
571 		    usbd_errstr(error));
572 
573 		if (error != USB_ERR_CANCELLED) {
574 			/* try to clear stall first */
575 			usbd_xfer_set_stall(xfer);
576 			goto tr_setup;
577 		}
578 		return;
579 	}
580 }
581 
582 static void
583 kue_bulk_write_callback(struct usb_xfer *xfer, usb_error_t error)
584 {
585 	struct kue_softc *sc = usbd_xfer_softc(xfer);
586 	struct ifnet *ifp = uether_getifp(&sc->sc_ue);
587 	struct usb_page_cache *pc;
588 	struct mbuf *m;
589 	int total_len;
590 	int temp_len;
591 	uint8_t buf[2];
592 
593 	switch (USB_GET_STATE(xfer)) {
594 	case USB_ST_TRANSFERRED:
595 		DPRINTFN(11, "transfer complete\n");
596 		if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
597 
598 		/* FALLTHROUGH */
599 	case USB_ST_SETUP:
600 tr_setup:
601 		IFQ_DRV_DEQUEUE(&ifp->if_snd, m);
602 
603 		if (m == NULL)
604 			return;
605 		if (m->m_pkthdr.len > MCLBYTES)
606 			m->m_pkthdr.len = MCLBYTES;
607 		temp_len = (m->m_pkthdr.len + 2);
608 		total_len = (temp_len + (64 - (temp_len % 64)));
609 
610 		/* the first two bytes are the frame length */
611 
612 		buf[0] = (uint8_t)(m->m_pkthdr.len);
613 		buf[1] = (uint8_t)(m->m_pkthdr.len >> 8);
614 
615 		pc = usbd_xfer_get_frame(xfer, 0);
616 		usbd_copy_in(pc, 0, buf, 2);
617 		usbd_m_copy_in(pc, 2, m, 0, m->m_pkthdr.len);
618 
619 		usbd_frame_zero(pc, temp_len, total_len - temp_len);
620 		usbd_xfer_set_frame_len(xfer, 0, total_len);
621 
622 		/*
623 		 * if there's a BPF listener, bounce a copy
624 		 * of this frame to him:
625 		 */
626 		BPF_MTAP(ifp, m);
627 
628 		m_freem(m);
629 
630 		usbd_transfer_submit(xfer);
631 
632 		return;
633 
634 	default:			/* Error */
635 		DPRINTFN(11, "transfer error, %s\n",
636 		    usbd_errstr(error));
637 
638 		if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
639 
640 		if (error != USB_ERR_CANCELLED) {
641 			/* try to clear stall first */
642 			usbd_xfer_set_stall(xfer);
643 			goto tr_setup;
644 		}
645 		return;
646 	}
647 }
648 
649 static void
650 kue_start(struct usb_ether *ue)
651 {
652 	struct kue_softc *sc = uether_getsc(ue);
653 
654 	/*
655 	 * start the USB transfers, if not already started:
656 	 */
657 	usbd_transfer_start(sc->sc_xfer[KUE_BULK_DT_RD]);
658 	usbd_transfer_start(sc->sc_xfer[KUE_BULK_DT_WR]);
659 }
660 
661 static void
662 kue_init(struct usb_ether *ue)
663 {
664 	struct kue_softc *sc = uether_getsc(ue);
665 	struct ifnet *ifp = uether_getifp(ue);
666 
667 	KUE_LOCK_ASSERT(sc, MA_OWNED);
668 
669 	/* set MAC address */
670 	kue_ctl(sc, KUE_CTL_WRITE, KUE_CMD_SET_MAC,
671 	    0, IF_LLADDR(ifp), ETHER_ADDR_LEN);
672 
673 	/* I'm not sure how to tune these. */
674 #if 0
675 	/*
676 	 * Leave this one alone for now; setting it
677 	 * wrong causes lockups on some machines/controllers.
678 	 */
679 	kue_setword(sc, KUE_CMD_SET_SOFS, 1);
680 #endif
681 	kue_setword(sc, KUE_CMD_SET_URB_SIZE, 64);
682 
683 	/* load the multicast filter */
684 	kue_setpromisc(ue);
685 
686 	usbd_xfer_set_stall(sc->sc_xfer[KUE_BULK_DT_WR]);
687 
688 	ifp->if_drv_flags |= IFF_DRV_RUNNING;
689 	kue_start(ue);
690 }
691 
692 static void
693 kue_stop(struct usb_ether *ue)
694 {
695 	struct kue_softc *sc = uether_getsc(ue);
696 	struct ifnet *ifp = uether_getifp(ue);
697 
698 	KUE_LOCK_ASSERT(sc, MA_OWNED);
699 
700 	ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
701 
702 	/*
703 	 * stop all the transfers, if not already stopped:
704 	 */
705 	usbd_transfer_stop(sc->sc_xfer[KUE_BULK_DT_WR]);
706 	usbd_transfer_stop(sc->sc_xfer[KUE_BULK_DT_RD]);
707 }
708