xref: /freebsd/sys/dev/mmc/mmcsd.c (revision c6db8143eda5c775467145ac73e8ebec47afdd8f)
1 /*-
2  * Copyright (c) 2006 Bernd Walter.  All rights reserved.
3  * Copyright (c) 2006 M. Warner Losh.  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  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  *
25  * Portions of this software may have been developed with reference to
26  * the SD Simplified Specification.  The following disclaimer may apply:
27  *
28  * The following conditions apply to the release of the simplified
29  * specification ("Simplified Specification") by the SD Card Association and
30  * the SD Group. The Simplified Specification is a subset of the complete SD
31  * Specification which is owned by the SD Card Association and the SD
32  * Group. This Simplified Specification is provided on a non-confidential
33  * basis subject to the disclaimers below. Any implementation of the
34  * Simplified Specification may require a license from the SD Card
35  * Association, SD Group, SD-3C LLC or other third parties.
36  *
37  * Disclaimers:
38  *
39  * The information contained in the Simplified Specification is presented only
40  * as a standard specification for SD Cards and SD Host/Ancillary products and
41  * is provided "AS-IS" without any representations or warranties of any
42  * kind. No responsibility is assumed by the SD Group, SD-3C LLC or the SD
43  * Card Association for any damages, any infringements of patents or other
44  * right of the SD Group, SD-3C LLC, the SD Card Association or any third
45  * parties, which may result from its use. No license is granted by
46  * implication, estoppel or otherwise under any patent or other rights of the
47  * SD Group, SD-3C LLC, the SD Card Association or any third party. Nothing
48  * herein shall be construed as an obligation by the SD Group, the SD-3C LLC
49  * or the SD Card Association to disclose or distribute any technical
50  * information, know-how or other confidential information to any third party.
51  */
52 
53 #include <sys/cdefs.h>
54 __FBSDID("$FreeBSD$");
55 
56 #include <sys/param.h>
57 #include <sys/systm.h>
58 #include <sys/bio.h>
59 #include <sys/bus.h>
60 #include <sys/conf.h>
61 #include <sys/kernel.h>
62 #include <sys/kthread.h>
63 #include <sys/lock.h>
64 #include <sys/malloc.h>
65 #include <sys/module.h>
66 #include <sys/mutex.h>
67 #include <geom/geom_disk.h>
68 
69 #include <dev/mmc/mmcbrvar.h>
70 #include <dev/mmc/mmcreg.h>
71 #include <dev/mmc/mmcvar.h>
72 
73 #include "mmcbus_if.h"
74 
75 #if __FreeBSD_version < 800002
76 #define	kproc_create	kthread_create
77 #define	kproc_exit	kthread_exit
78 #endif
79 
80 struct mmcsd_softc {
81 	device_t dev;
82 	struct mtx sc_mtx;
83 	struct disk *disk;
84 	struct proc *p;
85 	struct bio_queue_head bio_queue;
86 	daddr_t eblock, eend;	/* Range remaining after the last erase. */
87 	int running;
88 	int suspend;
89 };
90 
91 static const char *errmsg[] =
92 {
93 	"None",
94 	"Timeout",
95 	"Bad CRC",
96 	"Fifo",
97 	"Failed",
98 	"Invalid",
99 	"NO MEMORY"
100 };
101 
102 /* bus entry points */
103 static int mmcsd_attach(device_t dev);
104 static int mmcsd_detach(device_t dev);
105 static int mmcsd_probe(device_t dev);
106 
107 /* disk routines */
108 static int mmcsd_close(struct disk *dp);
109 static int mmcsd_dump(void *arg, void *virtual, vm_offset_t physical,
110 	off_t offset, size_t length);
111 static int mmcsd_open(struct disk *dp);
112 static void mmcsd_strategy(struct bio *bp);
113 static void mmcsd_task(void *arg);
114 
115 static int mmcsd_bus_bit_width(device_t dev);
116 static daddr_t mmcsd_delete(struct mmcsd_softc *sc, struct bio *bp);
117 static daddr_t mmcsd_rw(struct mmcsd_softc *sc, struct bio *bp);
118 
119 #define MMCSD_LOCK(_sc)		mtx_lock(&(_sc)->sc_mtx)
120 #define	MMCSD_UNLOCK(_sc)	mtx_unlock(&(_sc)->sc_mtx)
121 #define MMCSD_LOCK_INIT(_sc) \
122 	mtx_init(&_sc->sc_mtx, device_get_nameunit(_sc->dev), \
123 	    "mmcsd", MTX_DEF)
124 #define MMCSD_LOCK_DESTROY(_sc)	mtx_destroy(&_sc->sc_mtx);
125 #define MMCSD_ASSERT_LOCKED(_sc) mtx_assert(&_sc->sc_mtx, MA_OWNED);
126 #define MMCSD_ASSERT_UNLOCKED(_sc) mtx_assert(&_sc->sc_mtx, MA_NOTOWNED);
127 
128 static int
129 mmcsd_probe(device_t dev)
130 {
131 
132 	device_quiet(dev);
133 	device_set_desc(dev, "MMC/SD Memory Card");
134 	return (0);
135 }
136 
137 static int
138 mmcsd_attach(device_t dev)
139 {
140 	struct mmcsd_softc *sc;
141 	struct disk *d;
142 	intmax_t mb;
143 	uint32_t speed;
144 	uint32_t maxblocks;
145 	char unit;
146 
147 	sc = device_get_softc(dev);
148 	sc->dev = dev;
149 	MMCSD_LOCK_INIT(sc);
150 
151 	d = sc->disk = disk_alloc();
152 	d->d_open = mmcsd_open;
153 	d->d_close = mmcsd_close;
154 	d->d_strategy = mmcsd_strategy;
155 	d->d_dump = mmcsd_dump;
156 	d->d_name = "mmcsd";
157 	d->d_drv1 = sc;
158 	d->d_sectorsize = mmc_get_sector_size(dev);
159 	d->d_maxsize = mmc_get_max_data(dev) * d->d_sectorsize;
160 	d->d_mediasize = (off_t)mmc_get_media_size(dev) * d->d_sectorsize;
161 	d->d_stripeoffset = 0;
162 	d->d_stripesize = mmc_get_erase_sector(dev) * d->d_sectorsize;
163 	d->d_unit = device_get_unit(dev);
164 	d->d_flags = DISKFLAG_CANDELETE;
165 	d->d_delmaxsize = mmc_get_erase_sector(dev) * d->d_sectorsize * 1; /* conservative */
166 	/*
167 	 * The d_fw* values are fake. However, layout is aided by making the
168 	 * number of fwsectors equal to the erase sectors from the drive since
169 	 * we set the stripe size equal to that. We set fwheads such that there
170 	 * are ~20 cylinder groups since all values are somewhat arbitrary here
171 	 * and this gives good behavior with ffs without wasting too much
172 	 * space.  Sadly, geom_part wants to round partitions to these
173 	 * values. While not bad, in and of itself, the values we present here
174 	 * will almost certainly be different then the values that USB SD
175 	 * adapters use and there's too much variation between brands to just
176 	 * use those values here.  Also SD to ATA adapters favor traditional
177 	 * ata sizes, which are different again from the USB adapters (which
178 	 * favor SCSI values). This rounding leads to a loss of up to 5% of the
179 	 * usable space (usually much less, but that's why 20 was selected: to
180 	 * limit this effect at a few percent). gpart needs a way to override
181 	 * this behavior for situations like this, but doesn't provide
182 	 * one. Perhaps this behavior should be tunable as well, but maybe that
183 	 * belongs in the disk layer.  These values will be much better than
184 	 * the default ones.
185 	 */
186 	d->d_fwsectors = mmc_get_erase_sector(dev);
187 	d->d_fwheads = mmc_get_media_size(dev) / (d->d_fwsectors * 20);
188 	strlcpy(d->d_ident, mmc_get_card_sn_string(dev), sizeof(d->d_ident));
189 	strlcpy(d->d_descr, mmc_get_card_id_string(dev), sizeof(d->d_descr));
190 
191 	/*
192 	 * Display in most natural units.  There's no cards < 1MB.  The SD
193 	 * standard goes to 2GiB due to its reliance on FAT, but the data
194 	 * format supports up to 4GiB and some card makers push it up to this
195 	 * limit.  The SDHC standard only goes to 32GiB due to FAT32, but the
196 	 * data format supports up to 2TiB however. 2048GB isn't too ugly, so
197 	 * we note it in passing here and don't add the code to print
198 	 * TB). Since these cards are sold in terms of MB and GB not MiB and
199 	 * GiB, report them like that. We also round to the nearest unit, since
200 	 * many cards are a few percent short, even of the power of 10 size.
201 	 */
202 	mb = (d->d_mediasize + 1000000 / 2 - 1) / 1000000;
203 	unit = 'M';
204 	if (mb >= 1000) {
205 		unit = 'G';
206 		mb = (mb + 1000 / 2 - 1) / 1000;
207 	}
208 	/*
209 	 * Report the clock speed of the underlying hardware, which might be
210 	 * different than what the card reports due to hardware limitations.
211 	 * Report how many blocks the hardware transfers at once.
212 	 */
213 	speed = mmcbr_get_clock(device_get_parent(dev));
214 	maxblocks = mmc_get_max_data(dev);
215 	device_printf(dev, "%ju%cB <%s>%s at %s %d.%01dMHz/%dbit/%d-block\n",
216 	    mb, unit, d->d_descr,
217 	    mmc_get_read_only(dev) ? " (read-only)" : "",
218 	    device_get_nameunit(device_get_parent(dev)),
219 	    speed / 1000000, (speed / 100000) % 10,
220 	    mmcsd_bus_bit_width(dev), maxblocks);
221 	disk_create(d, DISK_VERSION);
222 	bioq_init(&sc->bio_queue);
223 
224 	sc->running = 1;
225 	sc->suspend = 0;
226 	sc->eblock = sc->eend = 0;
227 	kproc_create(&mmcsd_task, sc, &sc->p, 0, 0, "%s: mmc/sd card",
228 	    device_get_nameunit(dev));
229 
230 	return (0);
231 }
232 
233 static int
234 mmcsd_detach(device_t dev)
235 {
236 	struct mmcsd_softc *sc = device_get_softc(dev);
237 
238 	MMCSD_LOCK(sc);
239 	sc->suspend = 0;
240 	if (sc->running > 0) {
241 		/* kill thread */
242 		sc->running = 0;
243 		wakeup(sc);
244 		/* wait for thread to finish. */
245 		while (sc->running != -1)
246 			msleep(sc, &sc->sc_mtx, 0, "detach", 0);
247 	}
248 	MMCSD_UNLOCK(sc);
249 
250 	/* Flush the request queue. */
251 	bioq_flush(&sc->bio_queue, NULL, ENXIO);
252 	/* kill disk */
253 	disk_destroy(sc->disk);
254 
255 	MMCSD_LOCK_DESTROY(sc);
256 
257 	return (0);
258 }
259 
260 static int
261 mmcsd_suspend(device_t dev)
262 {
263 	struct mmcsd_softc *sc = device_get_softc(dev);
264 
265 	MMCSD_LOCK(sc);
266 	sc->suspend = 1;
267 	if (sc->running > 0) {
268 		/* kill thread */
269 		sc->running = 0;
270 		wakeup(sc);
271 		/* wait for thread to finish. */
272 		while (sc->running != -1)
273 			msleep(sc, &sc->sc_mtx, 0, "detach", 0);
274 	}
275 	MMCSD_UNLOCK(sc);
276 	return (0);
277 }
278 
279 static int
280 mmcsd_resume(device_t dev)
281 {
282 	struct mmcsd_softc *sc = device_get_softc(dev);
283 
284 	MMCSD_LOCK(sc);
285 	sc->suspend = 0;
286 	if (sc->running <= 0) {
287 		sc->running = 1;
288 		MMCSD_UNLOCK(sc);
289 		kproc_create(&mmcsd_task, sc, &sc->p, 0, 0, "%s: mmc/sd card",
290 		    device_get_nameunit(dev));
291 	} else
292 		MMCSD_UNLOCK(sc);
293 	return (0);
294 }
295 
296 static int
297 mmcsd_open(struct disk *dp)
298 {
299 
300 	return (0);
301 }
302 
303 static int
304 mmcsd_close(struct disk *dp)
305 {
306 
307 	return (0);
308 }
309 
310 static void
311 mmcsd_strategy(struct bio *bp)
312 {
313 	struct mmcsd_softc *sc;
314 
315 	sc = (struct mmcsd_softc *)bp->bio_disk->d_drv1;
316 	MMCSD_LOCK(sc);
317 	if (sc->running > 0 || sc->suspend > 0) {
318 		bioq_disksort(&sc->bio_queue, bp);
319 		MMCSD_UNLOCK(sc);
320 		wakeup(sc);
321 	} else {
322 		MMCSD_UNLOCK(sc);
323 		biofinish(bp, NULL, ENXIO);
324 	}
325 }
326 
327 static const char *
328 mmcsd_errmsg(int e)
329 {
330 	if (e < 0 || e > MMC_ERR_MAX)
331 		return "Bad error code";
332 	return errmsg[e];
333 }
334 
335 static daddr_t
336 mmcsd_rw(struct mmcsd_softc *sc, struct bio *bp)
337 {
338 	daddr_t block, end;
339 	struct mmc_command cmd;
340 	struct mmc_command stop;
341 	struct mmc_request req;
342 	struct mmc_data data;
343 	device_t dev = sc->dev;
344 	int sz = sc->disk->d_sectorsize;
345 	device_t mmcbr = device_get_parent(dev);
346 
347 	block = bp->bio_pblkno;
348 	end = bp->bio_pblkno + (bp->bio_bcount / sz);
349 	while (block < end) {
350 		char *vaddr = bp->bio_data +
351 		    (block - bp->bio_pblkno) * sz;
352 		int numblocks = min(end - block, mmc_get_max_data(dev));
353 		memset(&req, 0, sizeof(req));
354     		memset(&cmd, 0, sizeof(cmd));
355 		memset(&stop, 0, sizeof(stop));
356 		memset(&data, 0, sizeof(data));
357 		cmd.mrq = &req;
358 		req.cmd = &cmd;
359 		cmd.data = &data;
360 		if (bp->bio_cmd == BIO_READ) {
361 			if (numblocks > 1)
362 				cmd.opcode = MMC_READ_MULTIPLE_BLOCK;
363 			else
364 				cmd.opcode = MMC_READ_SINGLE_BLOCK;
365 		} else {
366 			if (numblocks > 1)
367 				cmd.opcode = MMC_WRITE_MULTIPLE_BLOCK;
368 			else
369 				cmd.opcode = MMC_WRITE_BLOCK;
370 		}
371 		cmd.arg = block;
372 		if (!mmc_get_high_cap(dev))
373 			cmd.arg <<= 9;
374 		cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
375 		data.data = vaddr;
376 		data.mrq = &req;
377 		if (bp->bio_cmd == BIO_READ)
378 			data.flags = MMC_DATA_READ;
379 		else
380 			data.flags = MMC_DATA_WRITE;
381 		data.len = numblocks * sz;
382 		if (numblocks > 1) {
383 			data.flags |= MMC_DATA_MULTI;
384 			stop.opcode = MMC_STOP_TRANSMISSION;
385 			stop.arg = 0;
386 			stop.flags = MMC_RSP_R1B | MMC_CMD_AC;
387 			stop.mrq = &req;
388 			req.stop = &stop;
389 		}
390 		MMCBUS_WAIT_FOR_REQUEST(mmcbr, dev, &req);
391 		if (req.cmd->error != MMC_ERR_NONE) {
392 			device_printf(dev, "Error indicated: %d %s\n",
393 			    req.cmd->error, mmcsd_errmsg(req.cmd->error));
394 			break;
395 		}
396 		block += numblocks;
397 	}
398 	return (block);
399 }
400 
401 static daddr_t
402 mmcsd_delete(struct mmcsd_softc *sc, struct bio *bp)
403 {
404 	daddr_t block, end, start, stop;
405 	struct mmc_command cmd;
406 	struct mmc_request req;
407 	device_t dev = sc->dev;
408 	int sz = sc->disk->d_sectorsize;
409 	int erase_sector;
410 	device_t mmcbr = device_get_parent(dev);
411 
412 	block = bp->bio_pblkno;
413 	end = bp->bio_pblkno + (bp->bio_bcount / sz);
414 	/* Coalesce with part remaining from previous request. */
415 	if (block > sc->eblock && block <= sc->eend)
416 		block = sc->eblock;
417 	if (end >= sc->eblock && end < sc->eend)
418 		end = sc->eend;
419 	/* Safe round to the erase sector boundaries. */
420 	erase_sector = mmc_get_erase_sector(dev);
421 	start = block + erase_sector - 1;	 /* Round up. */
422 	start -= start % erase_sector;
423 	stop = end;				/* Round down. */
424 	stop -= end % erase_sector;
425 	/* We can't erase area smaller then sector, store it for later. */
426 	if (start >= stop) {
427 		sc->eblock = block;
428 		sc->eend = end;
429 		return (end);
430 	}
431 
432 	/* Set erase start position. */
433 	memset(&req, 0, sizeof(req));
434 	memset(&cmd, 0, sizeof(cmd));
435 	cmd.mrq = &req;
436 	req.cmd = &cmd;
437 	if (mmc_get_card_type(dev) == mode_sd)
438 		cmd.opcode = SD_ERASE_WR_BLK_START;
439 	else
440 		cmd.opcode = MMC_ERASE_GROUP_START;
441 	cmd.arg = start;
442 	if (!mmc_get_high_cap(dev))
443 		cmd.arg <<= 9;
444 	cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
445 	MMCBUS_WAIT_FOR_REQUEST(mmcbr, dev, &req);
446 	if (req.cmd->error != MMC_ERR_NONE) {
447 	    printf("erase err1: %d\n", req.cmd->error);
448 	    return (block);
449 	}
450 	/* Set erase stop position. */
451 	memset(&req, 0, sizeof(req));
452 	memset(&cmd, 0, sizeof(cmd));
453 	req.cmd = &cmd;
454 	if (mmc_get_card_type(dev) == mode_sd)
455 		cmd.opcode = SD_ERASE_WR_BLK_END;
456 	else
457 		cmd.opcode = MMC_ERASE_GROUP_END;
458 	cmd.arg = stop;
459 	if (!mmc_get_high_cap(dev))
460 		cmd.arg <<= 9;
461 	cmd.arg--;
462 	cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
463 	MMCBUS_WAIT_FOR_REQUEST(mmcbr, dev, &req);
464 	if (req.cmd->error != MMC_ERR_NONE) {
465 	    printf("erase err2: %d\n", req.cmd->error);
466 	    return (block);
467 	}
468 	/* Erase range. */
469 	memset(&req, 0, sizeof(req));
470 	memset(&cmd, 0, sizeof(cmd));
471 	req.cmd = &cmd;
472 	cmd.opcode = MMC_ERASE;
473 	cmd.arg = 0;
474 	cmd.flags = MMC_RSP_R1B | MMC_CMD_AC;
475 	MMCBUS_WAIT_FOR_REQUEST(mmcbr, dev, &req);
476 	if (req.cmd->error != MMC_ERR_NONE) {
477 	    printf("erase err3 %d\n", req.cmd->error);
478 	    return (block);
479 	}
480 	/* Store one of remaining parts for the next call. */
481 	if (bp->bio_pblkno >= sc->eblock || block == start) {
482 		sc->eblock = stop;	/* Predict next forward. */
483 		sc->eend = end;
484 	} else {
485 		sc->eblock = block;	/* Predict next backward. */
486 		sc->eend = start;
487 	}
488 	return (end);
489 }
490 
491 static int
492 mmcsd_dump(void *arg, void *virtual, vm_offset_t physical,
493 	off_t offset, size_t length)
494 {
495 	struct disk *disk = arg;
496 	struct mmcsd_softc *sc = (struct mmcsd_softc *)disk->d_drv1;
497 	device_t dev = sc->dev;
498 	struct bio bp;
499 	daddr_t block, end;
500 	device_t mmcbr = device_get_parent(dev);
501 
502 	/* length zero is special and really means flush buffers to media */
503 	if (!length)
504 		return (0);
505 
506 	bzero(&bp, sizeof(struct bio));
507 	bp.bio_disk = disk;
508 	bp.bio_pblkno = offset / disk->d_sectorsize;
509 	bp.bio_bcount = length;
510 	bp.bio_data = virtual;
511 	bp.bio_cmd = BIO_WRITE;
512 	end = bp.bio_pblkno + bp.bio_bcount / sc->disk->d_sectorsize;
513 	MMCBUS_ACQUIRE_BUS(mmcbr, dev);
514 	block = mmcsd_rw(sc, &bp);
515 	MMCBUS_RELEASE_BUS(mmcbr, dev);
516 	return ((end < block) ? EIO : 0);
517 }
518 
519 static void
520 mmcsd_task(void *arg)
521 {
522 	struct mmcsd_softc *sc = (struct mmcsd_softc*)arg;
523 	struct bio *bp;
524 	int sz;
525 	daddr_t block, end;
526 	device_t dev = sc->dev;
527 	device_t mmcbr = device_get_parent(sc->dev);
528 
529 	while (1) {
530 		MMCSD_LOCK(sc);
531 		do {
532 			if (sc->running == 0)
533 				goto out;
534 			bp = bioq_takefirst(&sc->bio_queue);
535 			if (bp == NULL)
536 				msleep(sc, &sc->sc_mtx, PRIBIO, "jobqueue", 0);
537 		} while (bp == NULL);
538 		MMCSD_UNLOCK(sc);
539 		if (bp->bio_cmd != BIO_READ && mmc_get_read_only(dev)) {
540 			bp->bio_error = EROFS;
541 			bp->bio_resid = bp->bio_bcount;
542 			bp->bio_flags |= BIO_ERROR;
543 			biodone(bp);
544 			continue;
545 		}
546 		MMCBUS_ACQUIRE_BUS(mmcbr, dev);
547 		sz = sc->disk->d_sectorsize;
548 		block = bp->bio_pblkno;
549 		end = bp->bio_pblkno + (bp->bio_bcount / sz);
550 		if (bp->bio_cmd == BIO_READ || bp->bio_cmd == BIO_WRITE) {
551 			/* Access to the remaining erase block obsoletes it. */
552 			if (block < sc->eend && end > sc->eblock)
553 				sc->eblock = sc->eend = 0;
554 			block = mmcsd_rw(sc, bp);
555 		} else if (bp->bio_cmd == BIO_DELETE) {
556 			block = mmcsd_delete(sc, bp);
557 		}
558 		MMCBUS_RELEASE_BUS(mmcbr, dev);
559 		if (block < end) {
560 			bp->bio_error = EIO;
561 			bp->bio_resid = (end - block) * sz;
562 			bp->bio_flags |= BIO_ERROR;
563 		}
564 		biodone(bp);
565 	}
566 out:
567 	/* tell parent we're done */
568 	sc->running = -1;
569 	MMCSD_UNLOCK(sc);
570 	wakeup(sc);
571 
572 	kproc_exit(0);
573 }
574 
575 static int
576 mmcsd_bus_bit_width(device_t dev)
577 {
578 
579 	if (mmc_get_bus_width(dev) == bus_width_1)
580 		return (1);
581 	if (mmc_get_bus_width(dev) == bus_width_4)
582 		return (4);
583 	return (8);
584 }
585 
586 static device_method_t mmcsd_methods[] = {
587 	DEVMETHOD(device_probe, mmcsd_probe),
588 	DEVMETHOD(device_attach, mmcsd_attach),
589 	DEVMETHOD(device_detach, mmcsd_detach),
590 	DEVMETHOD(device_suspend, mmcsd_suspend),
591 	DEVMETHOD(device_resume, mmcsd_resume),
592 	DEVMETHOD_END
593 };
594 
595 static driver_t mmcsd_driver = {
596 	"mmcsd",
597 	mmcsd_methods,
598 	sizeof(struct mmcsd_softc),
599 };
600 static devclass_t mmcsd_devclass;
601 
602 DRIVER_MODULE(mmcsd, mmc, mmcsd_driver, mmcsd_devclass, NULL, NULL);
603