xref: /linux/drivers/mmc/core/sdio.c (revision b3b77c8caef1750ebeea1054e39e358550ea9f55)
1 /*
2  *  linux/drivers/mmc/sdio.c
3  *
4  *  Copyright 2006-2007 Pierre Ossman
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or (at
9  * your option) any later version.
10  */
11 
12 #include <linux/err.h>
13 
14 #include <linux/mmc/host.h>
15 #include <linux/mmc/card.h>
16 #include <linux/mmc/sdio.h>
17 #include <linux/mmc/sdio_func.h>
18 
19 #include "core.h"
20 #include "bus.h"
21 #include "sdio_bus.h"
22 #include "mmc_ops.h"
23 #include "sd_ops.h"
24 #include "sdio_ops.h"
25 #include "sdio_cis.h"
26 
27 static int sdio_read_fbr(struct sdio_func *func)
28 {
29 	int ret;
30 	unsigned char data;
31 
32 	ret = mmc_io_rw_direct(func->card, 0, 0,
33 		SDIO_FBR_BASE(func->num) + SDIO_FBR_STD_IF, 0, &data);
34 	if (ret)
35 		goto out;
36 
37 	data &= 0x0f;
38 
39 	if (data == 0x0f) {
40 		ret = mmc_io_rw_direct(func->card, 0, 0,
41 			SDIO_FBR_BASE(func->num) + SDIO_FBR_STD_IF_EXT, 0, &data);
42 		if (ret)
43 			goto out;
44 	}
45 
46 	func->class = data;
47 
48 out:
49 	return ret;
50 }
51 
52 static int sdio_init_func(struct mmc_card *card, unsigned int fn)
53 {
54 	int ret;
55 	struct sdio_func *func;
56 
57 	BUG_ON(fn > SDIO_MAX_FUNCS);
58 
59 	func = sdio_alloc_func(card);
60 	if (IS_ERR(func))
61 		return PTR_ERR(func);
62 
63 	func->num = fn;
64 
65 	ret = sdio_read_fbr(func);
66 	if (ret)
67 		goto fail;
68 
69 	ret = sdio_read_func_cis(func);
70 	if (ret)
71 		goto fail;
72 
73 	card->sdio_func[fn - 1] = func;
74 
75 	return 0;
76 
77 fail:
78 	/*
79 	 * It is okay to remove the function here even though we hold
80 	 * the host lock as we haven't registered the device yet.
81 	 */
82 	sdio_remove_func(func);
83 	return ret;
84 }
85 
86 static int sdio_read_cccr(struct mmc_card *card)
87 {
88 	int ret;
89 	int cccr_vsn;
90 	unsigned char data;
91 
92 	memset(&card->cccr, 0, sizeof(struct sdio_cccr));
93 
94 	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_CCCR, 0, &data);
95 	if (ret)
96 		goto out;
97 
98 	cccr_vsn = data & 0x0f;
99 
100 	if (cccr_vsn > SDIO_CCCR_REV_1_20) {
101 		printk(KERN_ERR "%s: unrecognised CCCR structure version %d\n",
102 			mmc_hostname(card->host), cccr_vsn);
103 		return -EINVAL;
104 	}
105 
106 	card->cccr.sdio_vsn = (data & 0xf0) >> 4;
107 
108 	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_CAPS, 0, &data);
109 	if (ret)
110 		goto out;
111 
112 	if (data & SDIO_CCCR_CAP_SMB)
113 		card->cccr.multi_block = 1;
114 	if (data & SDIO_CCCR_CAP_LSC)
115 		card->cccr.low_speed = 1;
116 	if (data & SDIO_CCCR_CAP_4BLS)
117 		card->cccr.wide_bus = 1;
118 
119 	if (cccr_vsn >= SDIO_CCCR_REV_1_10) {
120 		ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_POWER, 0, &data);
121 		if (ret)
122 			goto out;
123 
124 		if (data & SDIO_POWER_SMPC)
125 			card->cccr.high_power = 1;
126 	}
127 
128 	if (cccr_vsn >= SDIO_CCCR_REV_1_20) {
129 		ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &data);
130 		if (ret)
131 			goto out;
132 
133 		if (data & SDIO_SPEED_SHS)
134 			card->cccr.high_speed = 1;
135 	}
136 
137 out:
138 	return ret;
139 }
140 
141 static int sdio_enable_wide(struct mmc_card *card)
142 {
143 	int ret;
144 	u8 ctrl;
145 
146 	if (!(card->host->caps & MMC_CAP_4_BIT_DATA))
147 		return 0;
148 
149 	if (card->cccr.low_speed && !card->cccr.wide_bus)
150 		return 0;
151 
152 	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_IF, 0, &ctrl);
153 	if (ret)
154 		return ret;
155 
156 	ctrl |= SDIO_BUS_WIDTH_4BIT;
157 
158 	ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_IF, ctrl, NULL);
159 	if (ret)
160 		return ret;
161 
162 	mmc_set_bus_width(card->host, MMC_BUS_WIDTH_4);
163 
164 	return 0;
165 }
166 
167 /*
168  * If desired, disconnect the pull-up resistor on CD/DAT[3] (pin 1)
169  * of the card. This may be required on certain setups of boards,
170  * controllers and embedded sdio device which do not need the card's
171  * pull-up. As a result, card detection is disabled and power is saved.
172  */
173 static int sdio_disable_cd(struct mmc_card *card)
174 {
175 	int ret;
176 	u8 ctrl;
177 
178 	if (!card->cccr.disable_cd)
179 		return 0;
180 
181 	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_IF, 0, &ctrl);
182 	if (ret)
183 		return ret;
184 
185 	ctrl |= SDIO_BUS_CD_DISABLE;
186 
187 	return mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_IF, ctrl, NULL);
188 }
189 
190 /*
191  * Devices that remain active during a system suspend are
192  * put back into 1-bit mode.
193  */
194 static int sdio_disable_wide(struct mmc_card *card)
195 {
196 	int ret;
197 	u8 ctrl;
198 
199 	if (!(card->host->caps & MMC_CAP_4_BIT_DATA))
200 		return 0;
201 
202 	if (card->cccr.low_speed && !card->cccr.wide_bus)
203 		return 0;
204 
205 	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_IF, 0, &ctrl);
206 	if (ret)
207 		return ret;
208 
209 	if (!(ctrl & SDIO_BUS_WIDTH_4BIT))
210 		return 0;
211 
212 	ctrl &= ~SDIO_BUS_WIDTH_4BIT;
213 	ctrl |= SDIO_BUS_ASYNC_INT;
214 
215 	ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_IF, ctrl, NULL);
216 	if (ret)
217 		return ret;
218 
219 	mmc_set_bus_width(card->host, MMC_BUS_WIDTH_1);
220 
221 	return 0;
222 }
223 
224 /*
225  * Test if the card supports high-speed mode and, if so, switch to it.
226  */
227 static int sdio_enable_hs(struct mmc_card *card)
228 {
229 	int ret;
230 	u8 speed;
231 
232 	if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED))
233 		return 0;
234 
235 	if (!card->cccr.high_speed)
236 		return 0;
237 
238 	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &speed);
239 	if (ret)
240 		return ret;
241 
242 	speed |= SDIO_SPEED_EHS;
243 
244 	ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_SPEED, speed, NULL);
245 	if (ret)
246 		return ret;
247 
248 	mmc_card_set_highspeed(card);
249 	mmc_set_timing(card->host, MMC_TIMING_SD_HS);
250 
251 	return 0;
252 }
253 
254 /*
255  * Handle the detection and initialisation of a card.
256  *
257  * In the case of a resume, "oldcard" will contain the card
258  * we're trying to reinitialise.
259  */
260 static int mmc_sdio_init_card(struct mmc_host *host, u32 ocr,
261 			      struct mmc_card *oldcard, int powered_resume)
262 {
263 	struct mmc_card *card;
264 	int err;
265 
266 	BUG_ON(!host);
267 	WARN_ON(!host->claimed);
268 
269 	/*
270 	 * Inform the card of the voltage
271 	 */
272 	if (!powered_resume) {
273 		err = mmc_send_io_op_cond(host, host->ocr, &ocr);
274 		if (err)
275 			goto err;
276 	}
277 
278 	/*
279 	 * For SPI, enable CRC as appropriate.
280 	 */
281 	if (mmc_host_is_spi(host)) {
282 		err = mmc_spi_set_crc(host, use_spi_crc);
283 		if (err)
284 			goto err;
285 	}
286 
287 	/*
288 	 * Allocate card structure.
289 	 */
290 	card = mmc_alloc_card(host, NULL);
291 	if (IS_ERR(card)) {
292 		err = PTR_ERR(card);
293 		goto err;
294 	}
295 
296 	card->type = MMC_TYPE_SDIO;
297 
298 	/*
299 	 * For native busses:  set card RCA and quit open drain mode.
300 	 */
301 	if (!powered_resume && !mmc_host_is_spi(host)) {
302 		err = mmc_send_relative_addr(host, &card->rca);
303 		if (err)
304 			goto remove;
305 
306 		mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
307 	}
308 
309 	/*
310 	 * Select card, as all following commands rely on that.
311 	 */
312 	if (!powered_resume && !mmc_host_is_spi(host)) {
313 		err = mmc_select_card(card);
314 		if (err)
315 			goto remove;
316 	}
317 
318 	/*
319 	 * Read the common registers.
320 	 */
321 	err = sdio_read_cccr(card);
322 	if (err)
323 		goto remove;
324 
325 	/*
326 	 * Read the common CIS tuples.
327 	 */
328 	err = sdio_read_common_cis(card);
329 	if (err)
330 		goto remove;
331 
332 	if (oldcard) {
333 		int same = (card->cis.vendor == oldcard->cis.vendor &&
334 			    card->cis.device == oldcard->cis.device);
335 		mmc_remove_card(card);
336 		if (!same) {
337 			err = -ENOENT;
338 			goto err;
339 		}
340 		card = oldcard;
341 		return 0;
342 	}
343 
344 	/*
345 	 * Switch to high-speed (if supported).
346 	 */
347 	err = sdio_enable_hs(card);
348 	if (err)
349 		goto remove;
350 
351 	/*
352 	 * Change to the card's maximum speed.
353 	 */
354 	if (mmc_card_highspeed(card)) {
355 		/*
356 		 * The SDIO specification doesn't mention how
357 		 * the CIS transfer speed register relates to
358 		 * high-speed, but it seems that 50 MHz is
359 		 * mandatory.
360 		 */
361 		mmc_set_clock(host, 50000000);
362 	} else {
363 		mmc_set_clock(host, card->cis.max_dtr);
364 	}
365 
366 	/*
367 	 * Switch to wider bus (if supported).
368 	 */
369 	err = sdio_enable_wide(card);
370 	if (err)
371 		goto remove;
372 
373 	if (!oldcard)
374 		host->card = card;
375 	return 0;
376 
377 remove:
378 	if (!oldcard)
379 		mmc_remove_card(card);
380 
381 err:
382 	return err;
383 }
384 
385 /*
386  * Host is being removed. Free up the current card.
387  */
388 static void mmc_sdio_remove(struct mmc_host *host)
389 {
390 	int i;
391 
392 	BUG_ON(!host);
393 	BUG_ON(!host->card);
394 
395 	for (i = 0;i < host->card->sdio_funcs;i++) {
396 		if (host->card->sdio_func[i]) {
397 			sdio_remove_func(host->card->sdio_func[i]);
398 			host->card->sdio_func[i] = NULL;
399 		}
400 	}
401 
402 	mmc_remove_card(host->card);
403 	host->card = NULL;
404 }
405 
406 /*
407  * Card detection callback from host.
408  */
409 static void mmc_sdio_detect(struct mmc_host *host)
410 {
411 	int err;
412 
413 	BUG_ON(!host);
414 	BUG_ON(!host->card);
415 
416 	mmc_claim_host(host);
417 
418 	/*
419 	 * Just check if our card has been removed.
420 	 */
421 	err = mmc_select_card(host->card);
422 
423 	mmc_release_host(host);
424 
425 	if (err) {
426 		mmc_sdio_remove(host);
427 
428 		mmc_claim_host(host);
429 		mmc_detach_bus(host);
430 		mmc_release_host(host);
431 	}
432 }
433 
434 /*
435  * SDIO suspend.  We need to suspend all functions separately.
436  * Therefore all registered functions must have drivers with suspend
437  * and resume methods.  Failing that we simply remove the whole card.
438  */
439 static int mmc_sdio_suspend(struct mmc_host *host)
440 {
441 	int i, err = 0;
442 
443 	for (i = 0; i < host->card->sdio_funcs; i++) {
444 		struct sdio_func *func = host->card->sdio_func[i];
445 		if (func && sdio_func_present(func) && func->dev.driver) {
446 			const struct dev_pm_ops *pmops = func->dev.driver->pm;
447 			if (!pmops || !pmops->suspend || !pmops->resume) {
448 				/* force removal of entire card in that case */
449 				err = -ENOSYS;
450 			} else
451 				err = pmops->suspend(&func->dev);
452 			if (err)
453 				break;
454 		}
455 	}
456 	while (err && --i >= 0) {
457 		struct sdio_func *func = host->card->sdio_func[i];
458 		if (func && sdio_func_present(func) && func->dev.driver) {
459 			const struct dev_pm_ops *pmops = func->dev.driver->pm;
460 			pmops->resume(&func->dev);
461 		}
462 	}
463 
464 	if (!err && host->pm_flags & MMC_PM_KEEP_POWER) {
465 		mmc_claim_host(host);
466 		sdio_disable_wide(host->card);
467 		mmc_release_host(host);
468 	}
469 
470 	return err;
471 }
472 
473 static int mmc_sdio_resume(struct mmc_host *host)
474 {
475 	int i, err;
476 
477 	BUG_ON(!host);
478 	BUG_ON(!host->card);
479 
480 	/* Basic card reinitialization. */
481 	mmc_claim_host(host);
482 	err = mmc_sdio_init_card(host, host->ocr, host->card,
483 				 (host->pm_flags & MMC_PM_KEEP_POWER));
484 	if (!err)
485 		/* We may have switched to 1-bit mode during suspend. */
486 		err = sdio_enable_wide(host->card);
487 	if (!err && host->sdio_irqs)
488 		mmc_signal_sdio_irq(host);
489 	mmc_release_host(host);
490 
491 	/*
492 	 * If the card looked to be the same as before suspending, then
493 	 * we proceed to resume all card functions.  If one of them returns
494 	 * an error then we simply return that error to the core and the
495 	 * card will be redetected as new.  It is the responsibility of
496 	 * the function driver to perform further tests with the extra
497 	 * knowledge it has of the card to confirm the card is indeed the
498 	 * same as before suspending (same MAC address for network cards,
499 	 * etc.) and return an error otherwise.
500 	 */
501 	for (i = 0; !err && i < host->card->sdio_funcs; i++) {
502 		struct sdio_func *func = host->card->sdio_func[i];
503 		if (func && sdio_func_present(func) && func->dev.driver) {
504 			const struct dev_pm_ops *pmops = func->dev.driver->pm;
505 			err = pmops->resume(&func->dev);
506 		}
507 	}
508 
509 	return err;
510 }
511 
512 static const struct mmc_bus_ops mmc_sdio_ops = {
513 	.remove = mmc_sdio_remove,
514 	.detect = mmc_sdio_detect,
515 	.suspend = mmc_sdio_suspend,
516 	.resume = mmc_sdio_resume,
517 };
518 
519 
520 /*
521  * Starting point for SDIO card init.
522  */
523 int mmc_attach_sdio(struct mmc_host *host, u32 ocr)
524 {
525 	int err;
526 	int i, funcs;
527 	struct mmc_card *card;
528 
529 	BUG_ON(!host);
530 	WARN_ON(!host->claimed);
531 
532 	mmc_attach_bus(host, &mmc_sdio_ops);
533 
534 	/*
535 	 * Sanity check the voltages that the card claims to
536 	 * support.
537 	 */
538 	if (ocr & 0x7F) {
539 		printk(KERN_WARNING "%s: card claims to support voltages "
540 		       "below the defined range. These will be ignored.\n",
541 		       mmc_hostname(host));
542 		ocr &= ~0x7F;
543 	}
544 
545 	host->ocr = mmc_select_voltage(host, ocr);
546 
547 	/*
548 	 * Can we support the voltage(s) of the card(s)?
549 	 */
550 	if (!host->ocr) {
551 		err = -EINVAL;
552 		goto err;
553 	}
554 
555 	/*
556 	 * Detect and init the card.
557 	 */
558 	err = mmc_sdio_init_card(host, host->ocr, NULL, 0);
559 	if (err)
560 		goto err;
561 	card = host->card;
562 
563 	/*
564 	 * The number of functions on the card is encoded inside
565 	 * the ocr.
566 	 */
567 	funcs = (ocr & 0x70000000) >> 28;
568 	card->sdio_funcs = 0;
569 
570 	/*
571 	 * If needed, disconnect card detection pull-up resistor.
572 	 */
573 	err = sdio_disable_cd(card);
574 	if (err)
575 		goto remove;
576 
577 	/*
578 	 * Initialize (but don't add) all present functions.
579 	 */
580 	for (i = 0; i < funcs; i++, card->sdio_funcs++) {
581 		err = sdio_init_func(host->card, i + 1);
582 		if (err)
583 			goto remove;
584 	}
585 
586 	mmc_release_host(host);
587 
588 	/*
589 	 * First add the card to the driver model...
590 	 */
591 	err = mmc_add_card(host->card);
592 	if (err)
593 		goto remove_added;
594 
595 	/*
596 	 * ...then the SDIO functions.
597 	 */
598 	for (i = 0;i < funcs;i++) {
599 		err = sdio_add_func(host->card->sdio_func[i]);
600 		if (err)
601 			goto remove_added;
602 	}
603 
604 	return 0;
605 
606 
607 remove_added:
608 	/* Remove without lock if the device has been added. */
609 	mmc_sdio_remove(host);
610 	mmc_claim_host(host);
611 remove:
612 	/* And with lock if it hasn't been added. */
613 	if (host->card)
614 		mmc_sdio_remove(host);
615 err:
616 	mmc_detach_bus(host);
617 	mmc_release_host(host);
618 
619 	printk(KERN_ERR "%s: error %d whilst initialising SDIO card\n",
620 		mmc_hostname(host), err);
621 
622 	return err;
623 }
624 
625