xref: /freebsd/sys/dev/mii/mii.c (revision 8881d206f4e68b564c2c5f50fc717086fc3e827a)
1 /*	$NetBSD: mii.c,v 1.12 1999/08/03 19:41:49 drochner Exp $	*/
2 
3 /*-
4  * SPDX-License-Identifier: BSD-2-Clause-NetBSD
5  *
6  * Copyright (c) 1998 The NetBSD Foundation, Inc.
7  * All rights reserved.
8  *
9  * This code is derived from software contributed to The NetBSD Foundation
10  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
11  * NASA Ames Research Center.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
23  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
24  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
25  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
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 THE
32  * POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 /*
39  * MII bus layer, glues MII-capable network interface drivers to sharable
40  * PHY drivers.  This exports an interface compatible with BSD/OS 3.0's,
41  * plus some NetBSD extensions.
42  */
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/socket.h>
47 #include <sys/malloc.h>
48 #include <sys/module.h>
49 #include <sys/bus.h>
50 #include <sys/sbuf.h>
51 
52 #include <net/if.h>
53 #include <net/if_var.h>
54 #include <net/if_media.h>
55 
56 #include <dev/mii/mii.h>
57 #include <dev/mii/miivar.h>
58 
59 MODULE_VERSION(miibus, 1);
60 
61 #include "miibus_if.h"
62 
63 static bus_child_detached_t miibus_child_detached;
64 static bus_child_location_t miibus_child_location;
65 static bus_child_pnpinfo_t miibus_child_pnpinfo;
66 static device_detach_t miibus_detach;
67 static bus_hinted_child_t miibus_hinted_child;
68 static bus_print_child_t miibus_print_child;
69 static device_probe_t miibus_probe;
70 static bus_read_ivar_t miibus_read_ivar;
71 static miibus_readreg_t miibus_readreg;
72 static miibus_statchg_t miibus_statchg;
73 static miibus_writereg_t miibus_writereg;
74 static miibus_linkchg_t miibus_linkchg;
75 static miibus_mediainit_t miibus_mediainit;
76 
77 static unsigned char mii_bitreverse(unsigned char x);
78 
79 static device_method_t miibus_methods[] = {
80 	/* device interface */
81 	DEVMETHOD(device_probe,		miibus_probe),
82 	DEVMETHOD(device_attach,	miibus_attach),
83 	DEVMETHOD(device_detach,	miibus_detach),
84 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
85 
86 	/* bus interface */
87 	DEVMETHOD(bus_print_child,	miibus_print_child),
88 	DEVMETHOD(bus_read_ivar,	miibus_read_ivar),
89 	DEVMETHOD(bus_child_detached,	miibus_child_detached),
90 	DEVMETHOD(bus_child_pnpinfo,	miibus_child_pnpinfo),
91 	DEVMETHOD(bus_child_location,	miibus_child_location),
92 	DEVMETHOD(bus_hinted_child,	miibus_hinted_child),
93 
94 	/* MII interface */
95 	DEVMETHOD(miibus_readreg,	miibus_readreg),
96 	DEVMETHOD(miibus_writereg,	miibus_writereg),
97 	DEVMETHOD(miibus_statchg,	miibus_statchg),
98 	DEVMETHOD(miibus_linkchg,	miibus_linkchg),
99 	DEVMETHOD(miibus_mediainit,	miibus_mediainit),
100 
101 	DEVMETHOD_END
102 };
103 
104 devclass_t miibus_devclass;
105 DEFINE_CLASS_0(miibus, miibus_driver, miibus_methods, sizeof(struct mii_data));
106 
107 struct miibus_ivars {
108 	if_t		ifp;
109 	ifm_change_cb_t	ifmedia_upd;
110 	ifm_stat_cb_t	ifmedia_sts;
111 	u_int		mii_flags;
112 	u_int		mii_offset;
113 };
114 
115 static int
116 miibus_probe(device_t dev)
117 {
118 
119 	device_set_desc(dev, "MII bus");
120 
121 	return (BUS_PROBE_SPECIFIC);
122 }
123 
124 int
125 miibus_attach(device_t dev)
126 {
127 	struct miibus_ivars	*ivars;
128 	struct mii_attach_args	*ma;
129 	struct mii_data		*mii;
130 	device_t		*children;
131 	int			i, nchildren;
132 
133 	mii = device_get_softc(dev);
134 	if (device_get_children(dev, &children, &nchildren) == 0) {
135 		for (i = 0; i < nchildren; i++) {
136 			ma = device_get_ivars(children[i]);
137 			ma->mii_data = mii;
138 		}
139 		free(children, M_TEMP);
140 	}
141 	if (nchildren == 0) {
142 		device_printf(dev, "cannot get children\n");
143 		return (ENXIO);
144 	}
145 	ivars = device_get_ivars(dev);
146 	ifmedia_init(&mii->mii_media, IFM_IMASK, ivars->ifmedia_upd,
147 	    ivars->ifmedia_sts);
148 	mii->mii_ifp = ivars->ifp;
149 	if_setcapabilitiesbit(mii->mii_ifp, IFCAP_LINKSTATE, 0);
150 	if_setcapenablebit(mii->mii_ifp, IFCAP_LINKSTATE, 0);
151 	LIST_INIT(&mii->mii_phys);
152 
153 	return (bus_generic_attach(dev));
154 }
155 
156 static int
157 miibus_detach(device_t dev)
158 {
159 	struct mii_data		*mii;
160 	struct miibus_ivars	*ivars;
161 
162 	ivars = device_get_ivars(dev);
163 	bus_generic_detach(dev);
164 	mii = device_get_softc(dev);
165 	ifmedia_removeall(&mii->mii_media);
166 	free(ivars, M_DEVBUF);
167 	mii->mii_ifp = NULL;
168 
169 	return (0);
170 }
171 
172 static void
173 miibus_child_detached(device_t dev, device_t child)
174 {
175 	struct mii_attach_args *args;
176 
177 	args = device_get_ivars(child);
178 	free(args, M_DEVBUF);
179 }
180 
181 static int
182 miibus_print_child(device_t dev, device_t child)
183 {
184 	struct mii_attach_args *ma;
185 	int retval;
186 
187 	ma = device_get_ivars(child);
188 	retval = bus_print_child_header(dev, child);
189 	retval += printf(" PHY %d", ma->mii_phyno);
190 	retval += bus_print_child_footer(dev, child);
191 
192 	return (retval);
193 }
194 
195 static int
196 miibus_read_ivar(device_t dev, device_t child __unused, int which,
197     uintptr_t *result)
198 {
199 	struct miibus_ivars *ivars;
200 
201 	/*
202 	 * NB: this uses the instance variables of the miibus rather than
203 	 * its PHY children.
204 	 */
205 	ivars = device_get_ivars(dev);
206 	switch (which) {
207 	case MIIBUS_IVAR_FLAGS:
208 		*result = ivars->mii_flags;
209 		break;
210 	default:
211 		return (ENOENT);
212 	}
213 	return (0);
214 }
215 
216 static int
217 miibus_child_pnpinfo(device_t dev __unused, device_t child, struct sbuf *sb)
218 {
219 	struct mii_attach_args *ma;
220 
221 	ma = device_get_ivars(child);
222 	sbuf_printf(sb, "oui=0x%x model=0x%x rev=0x%x",
223 	    MII_OUI(ma->mii_id1, ma->mii_id2),
224 	    MII_MODEL(ma->mii_id2), MII_REV(ma->mii_id2));
225 	return (0);
226 }
227 
228 static int
229 miibus_child_location(device_t dev __unused, device_t child, struct sbuf *sb)
230 {
231 	struct mii_attach_args *ma;
232 
233 	ma = device_get_ivars(child);
234 	sbuf_printf(sb, "phyno=%d", ma->mii_phyno);
235 	return (0);
236 }
237 
238 static void
239 miibus_hinted_child(device_t dev, const char *name, int unit)
240 {
241 	struct miibus_ivars *ivars;
242 	struct mii_attach_args *args, *ma;
243 	device_t *children, phy;
244 	int i, nchildren;
245 	u_int val;
246 
247 	if (resource_int_value(name, unit, "phyno", &val) != 0)
248 		return;
249 	if (device_get_children(dev, &children, &nchildren) != 0)
250 		return;
251 	ma = NULL;
252 	for (i = 0; i < nchildren; i++) {
253 		args = device_get_ivars(children[i]);
254 		if (args->mii_phyno == val) {
255 			ma = args;
256 			break;
257 		}
258 	}
259 	free(children, M_TEMP);
260 
261 	/*
262 	 * Don't add a PHY that was automatically identified by having media
263 	 * in its BMSR twice, only allow to alter its attach arguments.
264 	 */
265 	if (ma == NULL) {
266 		ma = malloc(sizeof(struct mii_attach_args), M_DEVBUF,
267 		    M_NOWAIT);
268 		if (ma == NULL)
269 			return;
270 		phy = device_add_child(dev, name, unit);
271 		if (phy == NULL) {
272 			free(ma, M_DEVBUF);
273 			return;
274 		}
275 		ivars = device_get_ivars(dev);
276 		ma->mii_phyno = val;
277 		ma->mii_offset = ivars->mii_offset++;
278 		ma->mii_id1 = 0;
279 		ma->mii_id2 = 0;
280 		ma->mii_capmask = BMSR_DEFCAPMASK;
281 		device_set_ivars(phy, ma);
282 	}
283 
284 	if (resource_int_value(name, unit, "id1", &val) == 0)
285 		ma->mii_id1 = val;
286 	if (resource_int_value(name, unit, "id2", &val) == 0)
287 		ma->mii_id2 = val;
288 	if (resource_int_value(name, unit, "capmask", &val) == 0)
289 		ma->mii_capmask = val;
290 }
291 
292 static int
293 miibus_readreg(device_t dev, int phy, int reg)
294 {
295 	device_t		parent;
296 
297 	parent = device_get_parent(dev);
298 	return (MIIBUS_READREG(parent, phy, reg));
299 }
300 
301 static int
302 miibus_writereg(device_t dev, int phy, int reg, int data)
303 {
304 	device_t		parent;
305 
306 	parent = device_get_parent(dev);
307 	return (MIIBUS_WRITEREG(parent, phy, reg, data));
308 }
309 
310 static void
311 miibus_statchg(device_t dev)
312 {
313 	device_t		parent;
314 	struct mii_data		*mii;
315 
316 	parent = device_get_parent(dev);
317 	MIIBUS_STATCHG(parent);
318 
319 	mii = device_get_softc(dev);
320 	if_setbaudrate(mii->mii_ifp, ifmedia_baudrate(mii->mii_media_active));
321 }
322 
323 static void
324 miibus_linkchg(device_t dev)
325 {
326 	struct mii_data		*mii;
327 	device_t		parent;
328 	int			link_state;
329 
330 	parent = device_get_parent(dev);
331 	MIIBUS_LINKCHG(parent);
332 
333 	mii = device_get_softc(dev);
334 
335 	if (mii->mii_media_status & IFM_AVALID) {
336 		if (mii->mii_media_status & IFM_ACTIVE)
337 			link_state = LINK_STATE_UP;
338 		else
339 			link_state = LINK_STATE_DOWN;
340 	} else
341 		link_state = LINK_STATE_UNKNOWN;
342 	if_link_state_change(mii->mii_ifp, link_state);
343 }
344 
345 static void
346 miibus_mediainit(device_t dev)
347 {
348 	struct mii_data		*mii;
349 	struct ifmedia_entry	*m;
350 	int			media = 0;
351 
352 	/* Poke the parent in case it has any media of its own to add. */
353 	MIIBUS_MEDIAINIT(device_get_parent(dev));
354 
355 	mii = device_get_softc(dev);
356 	LIST_FOREACH(m, &mii->mii_media.ifm_list, ifm_list) {
357 		media = m->ifm_media;
358 		if (media == (IFM_ETHER | IFM_AUTO))
359 			break;
360 	}
361 
362 	ifmedia_set(&mii->mii_media, media);
363 }
364 
365 /*
366  * Helper function used by network interface drivers, attaches the miibus and
367  * the PHYs to the network interface driver parent.
368  */
369 int
370 mii_attach(device_t dev, device_t *miibus, if_t ifp,
371     ifm_change_cb_t ifmedia_upd, ifm_stat_cb_t ifmedia_sts, int capmask,
372     int phyloc, int offloc, int flags)
373 {
374 	struct miibus_ivars *ivars;
375 	struct mii_attach_args *args, ma;
376 	device_t *children, phy;
377 	int bmsr, first, i, nchildren, phymax, phymin, rv;
378 	uint32_t phymask;
379 
380 	bus_topo_assert();
381 
382 	if (phyloc != MII_PHY_ANY && offloc != MII_OFFSET_ANY) {
383 		printf("%s: phyloc and offloc specified\n", __func__);
384 		return (EINVAL);
385 	}
386 
387 	if (offloc != MII_OFFSET_ANY && (offloc < 0 || offloc >= MII_NPHY)) {
388 		printf("%s: invalid offloc %d\n", __func__, offloc);
389 		return (EINVAL);
390 	}
391 
392 	if (phyloc == MII_PHY_ANY) {
393 		phymin = 0;
394 		phymax = MII_NPHY - 1;
395 	} else {
396 		if (phyloc < 0 || phyloc >= MII_NPHY) {
397 			printf("%s: invalid phyloc %d\n", __func__, phyloc);
398 			return (EINVAL);
399 		}
400 		phymin = phymax = phyloc;
401 	}
402 
403 	first = 0;
404 	if (*miibus == NULL) {
405 		first = 1;
406 		ivars = malloc(sizeof(*ivars), M_DEVBUF, M_NOWAIT);
407 		if (ivars == NULL)
408 			return (ENOMEM);
409 		ivars->ifp = ifp;
410 		ivars->ifmedia_upd = ifmedia_upd;
411 		ivars->ifmedia_sts = ifmedia_sts;
412 		ivars->mii_flags = flags;
413 		*miibus = device_add_child(dev, "miibus", -1);
414 		if (*miibus == NULL) {
415 			rv = ENXIO;
416 			goto fail;
417 		}
418 		device_set_ivars(*miibus, ivars);
419 	} else {
420 		ivars = device_get_ivars(*miibus);
421 		if (ivars->ifp != ifp || ivars->ifmedia_upd != ifmedia_upd ||
422 		    ivars->ifmedia_sts != ifmedia_sts ||
423 		    ivars->mii_flags != flags) {
424 			printf("%s: non-matching invariant\n", __func__);
425 			return (EINVAL);
426 		}
427 		/*
428 		 * Assignment of the attach arguments mii_data for the first
429 		 * pass is done in miibus_attach(), i.e. once the miibus softc
430 		 * has been allocated.
431 		 */
432 		ma.mii_data = device_get_softc(*miibus);
433 	}
434 
435 	ma.mii_capmask = capmask;
436 
437 	if (resource_int_value(device_get_name(*miibus),
438 	    device_get_unit(*miibus), "phymask", &phymask) != 0)
439 		phymask = 0xffffffff;
440 
441 	if (device_get_children(*miibus, &children, &nchildren) != 0) {
442 		children = NULL;
443 		nchildren = 0;
444 	}
445 	ivars->mii_offset = 0;
446 	for (ma.mii_phyno = phymin; ma.mii_phyno <= phymax; ma.mii_phyno++) {
447 		/*
448 		 * Make sure we haven't already configured a PHY at this
449 		 * address.  This allows mii_attach() to be called
450 		 * multiple times.
451 		 */
452 		for (i = 0; i < nchildren; i++) {
453 			args = device_get_ivars(children[i]);
454 			if (args->mii_phyno == ma.mii_phyno) {
455 				/*
456 				 * Yes, there is already something
457 				 * configured at this address.
458 				 */
459 				goto skip;
460 			}
461 		}
462 
463 		/*
464 		 * Check to see if there is a PHY at this address.  Note,
465 		 * many braindead PHYs report 0/0 in their ID registers,
466 		 * so we test for media in the BMSR.
467 		 */
468 		bmsr = MIIBUS_READREG(dev, ma.mii_phyno, MII_BMSR);
469 		if (bmsr == 0 || bmsr == 0xffff ||
470 		    (bmsr & (BMSR_EXTSTAT | BMSR_MEDIAMASK)) == 0) {
471 			/* Assume no PHY at this address. */
472 			continue;
473 		}
474 
475 		/*
476 		 * There is a PHY at this address.  If we were given an
477 		 * `offset' locator, skip this PHY if it doesn't match.
478 		 */
479 		if (offloc != MII_OFFSET_ANY && offloc != ivars->mii_offset)
480 			goto skip;
481 
482 		/*
483 		 * Skip this PHY if it's not included in the phymask hint.
484 		 */
485 		if ((phymask & (1 << ma.mii_phyno)) == 0)
486 			goto skip;
487 
488 		/*
489 		 * Extract the IDs.  Braindead PHYs will be handled by
490 		 * the `ukphy' driver, as we have no ID information to
491 		 * match on.
492 		 */
493 		ma.mii_id1 = MIIBUS_READREG(dev, ma.mii_phyno, MII_PHYIDR1);
494 		ma.mii_id2 = MIIBUS_READREG(dev, ma.mii_phyno, MII_PHYIDR2);
495 
496 		ma.mii_offset = ivars->mii_offset;
497 		args = malloc(sizeof(struct mii_attach_args), M_DEVBUF,
498 		    M_NOWAIT);
499 		if (args == NULL)
500 			goto skip;
501 		bcopy((char *)&ma, (char *)args, sizeof(ma));
502 		phy = device_add_child(*miibus, NULL, -1);
503 		if (phy == NULL) {
504 			free(args, M_DEVBUF);
505 			goto skip;
506 		}
507 		device_set_ivars(phy, args);
508  skip:
509 		ivars->mii_offset++;
510 	}
511 	free(children, M_TEMP);
512 
513 	if (first != 0) {
514 		rv = device_set_driver(*miibus, &miibus_driver);
515 		if (rv != 0)
516 			goto fail;
517 		bus_enumerate_hinted_children(*miibus);
518 		rv = device_get_children(*miibus, &children, &nchildren);
519 		if (rv != 0)
520 			goto fail;
521 		free(children, M_TEMP);
522 		if (nchildren == 0) {
523 			rv = ENXIO;
524 			goto fail;
525 		}
526 		rv = bus_generic_attach(dev);
527 		if (rv != 0)
528 			goto fail;
529 
530 		/* Attaching of the PHY drivers is done in miibus_attach(). */
531 		return (0);
532 	}
533 	rv = bus_generic_attach(*miibus);
534 	if (rv != 0)
535 		goto fail;
536 
537 	return (0);
538 
539  fail:
540 	if (*miibus != NULL)
541 		device_delete_child(dev, *miibus);
542 	free(ivars, M_DEVBUF);
543 	if (first != 0)
544 		*miibus = NULL;
545 	return (rv);
546 }
547 
548 /*
549  * Media changed; notify all PHYs.
550  */
551 int
552 mii_mediachg(struct mii_data *mii)
553 {
554 	struct mii_softc *child;
555 	struct ifmedia_entry *ife = mii->mii_media.ifm_cur;
556 	int rv;
557 
558 	mii->mii_media_status = 0;
559 	mii->mii_media_active = IFM_NONE;
560 
561 	LIST_FOREACH(child, &mii->mii_phys, mii_list) {
562 		/*
563 		 * If the media indicates a different PHY instance,
564 		 * isolate this one.
565 		 */
566 		if (IFM_INST(ife->ifm_media) != child->mii_inst) {
567 			if ((child->mii_flags & MIIF_NOISOLATE) != 0) {
568 				device_printf(child->mii_dev, "%s: "
569 				    "can't handle non-zero PHY instance %d\n",
570 				    __func__, child->mii_inst);
571 				continue;
572 			}
573 			PHY_WRITE(child, MII_BMCR, PHY_READ(child, MII_BMCR) |
574 			    BMCR_ISO);
575 			continue;
576 		}
577 		rv = PHY_SERVICE(child, mii, MII_MEDIACHG);
578 		if (rv)
579 			return (rv);
580 	}
581 	return (0);
582 }
583 
584 /*
585  * Call the PHY tick routines, used during autonegotiation.
586  */
587 void
588 mii_tick(struct mii_data *mii)
589 {
590 	struct mii_softc *child;
591 	struct ifmedia_entry *ife = mii->mii_media.ifm_cur;
592 
593 	LIST_FOREACH(child, &mii->mii_phys, mii_list) {
594 		/*
595 		 * If this PHY instance isn't currently selected, just skip
596 		 * it.
597 		 */
598 		if (IFM_INST(ife->ifm_media) != child->mii_inst)
599 			continue;
600 		(void)PHY_SERVICE(child, mii, MII_TICK);
601 	}
602 }
603 
604 /*
605  * Get media status from PHYs.
606  */
607 void
608 mii_pollstat(struct mii_data *mii)
609 {
610 	struct mii_softc *child;
611 	struct ifmedia_entry *ife = mii->mii_media.ifm_cur;
612 
613 	mii->mii_media_status = 0;
614 	mii->mii_media_active = IFM_NONE;
615 
616 	LIST_FOREACH(child, &mii->mii_phys, mii_list) {
617 		/*
618 		 * If we're not polling this PHY instance, just skip it.
619 		 */
620 		if (IFM_INST(ife->ifm_media) != child->mii_inst)
621 			continue;
622 		(void)PHY_SERVICE(child, mii, MII_POLLSTAT);
623 	}
624 }
625 
626 static unsigned char
627 mii_bitreverse(unsigned char x)
628 {
629 	static unsigned const char nibbletab[16] = {
630 		0, 8, 4, 12, 2, 10, 6, 14, 1, 9, 5, 13, 3, 11, 7, 15
631 	};
632 
633 	return ((nibbletab[x & 15] << 4) | nibbletab[x >> 4]);
634 }
635 
636 u_int
637 mii_oui(u_int id1, u_int id2)
638 {
639 	u_int h;
640 
641 	h = (id1 << 6) | (id2 >> 10);
642 
643 	return ((mii_bitreverse(h >> 16) << 16) |
644 	    (mii_bitreverse((h >> 8) & 0xff) << 8) |
645 	    mii_bitreverse(h & 0xff));
646 }
647 
648 int
649 mii_phy_mac_match(struct mii_softc *mii, const char *name)
650 {
651 
652 	return (strcmp(device_get_name(device_get_parent(mii->mii_dev)),
653 	    name) == 0);
654 }
655 
656 int
657 mii_dev_mac_match(device_t parent, const char *name)
658 {
659 
660 	return (strcmp(device_get_name(device_get_parent(
661 	    device_get_parent(parent))), name) == 0);
662 }
663 
664 void *
665 mii_phy_mac_softc(struct mii_softc *mii)
666 {
667 
668 	return (device_get_softc(device_get_parent(mii->mii_dev)));
669 }
670 
671 void *
672 mii_dev_mac_softc(device_t parent)
673 {
674 
675 	return (device_get_softc(device_get_parent(device_get_parent(parent))));
676 }
677