xref: /linux/drivers/mmc/core/sdio.c (revision bc75dffadc063eb46200611cc41d1e2373219e11)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  linux/drivers/mmc/sdio.c
4  *
5  *  Copyright 2006-2007 Pierre Ossman
6  */
7 
8 #include <linux/err.h>
9 #include <linux/pm_runtime.h>
10 #include <linux/sysfs.h>
11 
12 #include <linux/mmc/host.h>
13 #include <linux/mmc/card.h>
14 #include <linux/mmc/mmc.h>
15 #include <linux/mmc/sdio.h>
16 #include <linux/mmc/sdio_func.h>
17 #include <linux/mmc/sdio_ids.h>
18 
19 #include "core.h"
20 #include "card.h"
21 #include "host.h"
22 #include "bus.h"
23 #include "quirks.h"
24 #include "sd.h"
25 #include "sdio_bus.h"
26 #include "mmc_ops.h"
27 #include "sd_ops.h"
28 #include "sdio_ops.h"
29 #include "sdio_cis.h"
30 
31 MMC_DEV_ATTR(vendor, "0x%04x\n", card->cis.vendor);
32 MMC_DEV_ATTR(device, "0x%04x\n", card->cis.device);
33 MMC_DEV_ATTR(revision, "%u.%u\n", card->major_rev, card->minor_rev);
34 MMC_DEV_ATTR(ocr, "0x%08x\n", card->ocr);
35 MMC_DEV_ATTR(rca, "0x%04x\n", card->rca);
36 
37 #define sdio_info_attr(num)									\
38 static ssize_t info##num##_show(struct device *dev, struct device_attribute *attr, char *buf)	\
39 {												\
40 	struct mmc_card *card = mmc_dev_to_card(dev);						\
41 												\
42 	if (num > card->num_info)								\
43 		return -ENODATA;								\
44 	if (!card->info[num - 1][0])								\
45 		return 0;									\
46 	return sysfs_emit(buf, "%s\n", card->info[num - 1]);					\
47 }												\
48 static DEVICE_ATTR_RO(info##num)
49 
50 sdio_info_attr(1);
51 sdio_info_attr(2);
52 sdio_info_attr(3);
53 sdio_info_attr(4);
54 
55 static struct attribute *sdio_std_attrs[] = {
56 	&dev_attr_vendor.attr,
57 	&dev_attr_device.attr,
58 	&dev_attr_revision.attr,
59 	&dev_attr_info1.attr,
60 	&dev_attr_info2.attr,
61 	&dev_attr_info3.attr,
62 	&dev_attr_info4.attr,
63 	&dev_attr_ocr.attr,
64 	&dev_attr_rca.attr,
65 	NULL,
66 };
67 ATTRIBUTE_GROUPS(sdio_std);
68 
69 static struct device_type sdio_type = {
70 	.groups = sdio_std_groups,
71 };
72 
73 static int sdio_read_fbr(struct sdio_func *func)
74 {
75 	int ret;
76 	unsigned char data;
77 
78 	if (mmc_card_nonstd_func_interface(func->card)) {
79 		func->class = SDIO_CLASS_NONE;
80 		return 0;
81 	}
82 
83 	ret = mmc_io_rw_direct(func->card, 0, 0,
84 		SDIO_FBR_BASE(func->num) + SDIO_FBR_STD_IF, 0, &data);
85 	if (ret)
86 		goto out;
87 
88 	data &= 0x0f;
89 
90 	if (data == 0x0f) {
91 		ret = mmc_io_rw_direct(func->card, 0, 0,
92 			SDIO_FBR_BASE(func->num) + SDIO_FBR_STD_IF_EXT, 0, &data);
93 		if (ret)
94 			goto out;
95 	}
96 
97 	func->class = data;
98 
99 out:
100 	return ret;
101 }
102 
103 static int sdio_init_func(struct mmc_card *card, unsigned int fn)
104 {
105 	int ret;
106 	struct sdio_func *func;
107 
108 	if (WARN_ON(fn > SDIO_MAX_FUNCS))
109 		return -EINVAL;
110 
111 	func = sdio_alloc_func(card);
112 	if (IS_ERR(func))
113 		return PTR_ERR(func);
114 
115 	func->num = fn;
116 
117 	if (!(card->quirks & MMC_QUIRK_NONSTD_SDIO)) {
118 		ret = sdio_read_fbr(func);
119 		if (ret)
120 			goto fail;
121 
122 		ret = sdio_read_func_cis(func);
123 		if (ret)
124 			goto fail;
125 	} else {
126 		func->vendor = func->card->cis.vendor;
127 		func->device = func->card->cis.device;
128 		func->max_blksize = func->card->cis.blksize;
129 	}
130 
131 	card->sdio_func[fn - 1] = func;
132 
133 	return 0;
134 
135 fail:
136 	/*
137 	 * It is okay to remove the function here even though we hold
138 	 * the host lock as we haven't registered the device yet.
139 	 */
140 	sdio_remove_func(func);
141 	return ret;
142 }
143 
144 static int sdio_read_cccr(struct mmc_card *card, u32 ocr)
145 {
146 	int ret;
147 	int cccr_vsn;
148 	int uhs = ocr & R4_18V_PRESENT;
149 	unsigned char data;
150 	unsigned char speed;
151 
152 	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_CCCR, 0, &data);
153 	if (ret)
154 		goto out;
155 
156 	cccr_vsn = data & 0x0f;
157 
158 	if (cccr_vsn > SDIO_CCCR_REV_3_00) {
159 		pr_err("%s: unrecognised CCCR structure version %d\n",
160 			mmc_hostname(card->host), cccr_vsn);
161 		return -EINVAL;
162 	}
163 
164 	card->cccr.sdio_vsn = (data & 0xf0) >> 4;
165 
166 	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_CAPS, 0, &data);
167 	if (ret)
168 		goto out;
169 
170 	if (data & SDIO_CCCR_CAP_SMB)
171 		card->cccr.multi_block = 1;
172 	if (data & SDIO_CCCR_CAP_LSC)
173 		card->cccr.low_speed = 1;
174 	if (data & SDIO_CCCR_CAP_4BLS)
175 		card->cccr.wide_bus = 1;
176 
177 	if (cccr_vsn >= SDIO_CCCR_REV_1_10) {
178 		ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_POWER, 0, &data);
179 		if (ret)
180 			goto out;
181 
182 		if (data & SDIO_POWER_SMPC)
183 			card->cccr.high_power = 1;
184 	}
185 
186 	if (cccr_vsn >= SDIO_CCCR_REV_1_20) {
187 		ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &speed);
188 		if (ret)
189 			goto out;
190 
191 		card->scr.sda_spec3 = 0;
192 		card->sw_caps.sd3_bus_mode = 0;
193 		card->sw_caps.sd3_drv_type = 0;
194 		if (cccr_vsn >= SDIO_CCCR_REV_3_00 && uhs) {
195 			card->scr.sda_spec3 = 1;
196 			ret = mmc_io_rw_direct(card, 0, 0,
197 				SDIO_CCCR_UHS, 0, &data);
198 			if (ret)
199 				goto out;
200 
201 			if (mmc_host_uhs(card->host)) {
202 				if (data & SDIO_UHS_DDR50)
203 					card->sw_caps.sd3_bus_mode
204 						|= SD_MODE_UHS_DDR50 | SD_MODE_UHS_SDR50
205 							| SD_MODE_UHS_SDR25 | SD_MODE_UHS_SDR12;
206 
207 				if (data & SDIO_UHS_SDR50)
208 					card->sw_caps.sd3_bus_mode
209 						|= SD_MODE_UHS_SDR50 | SD_MODE_UHS_SDR25
210 							| SD_MODE_UHS_SDR12;
211 
212 				if (data & SDIO_UHS_SDR104)
213 					card->sw_caps.sd3_bus_mode
214 						|= SD_MODE_UHS_SDR104 | SD_MODE_UHS_SDR50
215 							| SD_MODE_UHS_SDR25 | SD_MODE_UHS_SDR12;
216 			}
217 
218 			ret = mmc_io_rw_direct(card, 0, 0,
219 				SDIO_CCCR_DRIVE_STRENGTH, 0, &data);
220 			if (ret)
221 				goto out;
222 
223 			if (data & SDIO_DRIVE_SDTA)
224 				card->sw_caps.sd3_drv_type |= SD_DRIVER_TYPE_A;
225 			if (data & SDIO_DRIVE_SDTC)
226 				card->sw_caps.sd3_drv_type |= SD_DRIVER_TYPE_C;
227 			if (data & SDIO_DRIVE_SDTD)
228 				card->sw_caps.sd3_drv_type |= SD_DRIVER_TYPE_D;
229 
230 			ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_INTERRUPT_EXT, 0, &data);
231 			if (ret)
232 				goto out;
233 
234 			if (data & SDIO_INTERRUPT_EXT_SAI) {
235 				data |= SDIO_INTERRUPT_EXT_EAI;
236 				ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_INTERRUPT_EXT,
237 						       data, NULL);
238 				if (ret)
239 					goto out;
240 
241 				card->cccr.enable_async_irq = 1;
242 			}
243 		}
244 
245 		/* if no uhs mode ensure we check for high speed */
246 		if (!card->sw_caps.sd3_bus_mode) {
247 			if (speed & SDIO_SPEED_SHS) {
248 				card->cccr.high_speed = 1;
249 				card->sw_caps.hs_max_dtr = 50000000;
250 			} else {
251 				card->cccr.high_speed = 0;
252 				card->sw_caps.hs_max_dtr = 25000000;
253 			}
254 		}
255 	}
256 
257 out:
258 	return ret;
259 }
260 
261 static int sdio_enable_wide(struct mmc_card *card)
262 {
263 	int ret;
264 	u8 ctrl;
265 
266 	if (!(card->host->caps & MMC_CAP_4_BIT_DATA))
267 		return 0;
268 
269 	if (card->cccr.low_speed && !card->cccr.wide_bus)
270 		return 0;
271 
272 	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_IF, 0, &ctrl);
273 	if (ret)
274 		return ret;
275 
276 	if ((ctrl & SDIO_BUS_WIDTH_MASK) == SDIO_BUS_WIDTH_RESERVED)
277 		pr_warn("%s: SDIO_CCCR_IF is invalid: 0x%02x\n",
278 			mmc_hostname(card->host), ctrl);
279 
280 	/* set as 4-bit bus width */
281 	ctrl &= ~SDIO_BUS_WIDTH_MASK;
282 	ctrl |= SDIO_BUS_WIDTH_4BIT;
283 
284 	ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_IF, ctrl, NULL);
285 	if (ret)
286 		return ret;
287 
288 	return 1;
289 }
290 
291 /*
292  * If desired, disconnect the pull-up resistor on CD/DAT[3] (pin 1)
293  * of the card. This may be required on certain setups of boards,
294  * controllers and embedded sdio device which do not need the card's
295  * pull-up. As a result, card detection is disabled and power is saved.
296  */
297 static int sdio_disable_cd(struct mmc_card *card)
298 {
299 	int ret;
300 	u8 ctrl;
301 
302 	if (!mmc_card_disable_cd(card))
303 		return 0;
304 
305 	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_IF, 0, &ctrl);
306 	if (ret)
307 		return ret;
308 
309 	ctrl |= SDIO_BUS_CD_DISABLE;
310 
311 	return mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_IF, ctrl, NULL);
312 }
313 
314 /*
315  * Devices that remain active during a system suspend are
316  * put back into 1-bit mode.
317  */
318 static int sdio_disable_wide(struct mmc_card *card)
319 {
320 	int ret;
321 	u8 ctrl;
322 
323 	if (!(card->host->caps & MMC_CAP_4_BIT_DATA))
324 		return 0;
325 
326 	if (card->cccr.low_speed && !card->cccr.wide_bus)
327 		return 0;
328 
329 	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_IF, 0, &ctrl);
330 	if (ret)
331 		return ret;
332 
333 	if (!(ctrl & SDIO_BUS_WIDTH_4BIT))
334 		return 0;
335 
336 	ctrl &= ~SDIO_BUS_WIDTH_4BIT;
337 	ctrl |= SDIO_BUS_ASYNC_INT;
338 
339 	ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_IF, ctrl, NULL);
340 	if (ret)
341 		return ret;
342 
343 	mmc_set_bus_width(card->host, MMC_BUS_WIDTH_1);
344 
345 	return 0;
346 }
347 
348 static int sdio_disable_4bit_bus(struct mmc_card *card)
349 {
350 	int err;
351 
352 	if (mmc_card_sdio(card))
353 		goto out;
354 
355 	if (!(card->host->caps & MMC_CAP_4_BIT_DATA))
356 		return 0;
357 
358 	if (!(card->scr.bus_widths & SD_SCR_BUS_WIDTH_4))
359 		return 0;
360 
361 	err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_1);
362 	if (err)
363 		return err;
364 
365 out:
366 	return sdio_disable_wide(card);
367 }
368 
369 
370 static int sdio_enable_4bit_bus(struct mmc_card *card)
371 {
372 	int err;
373 
374 	err = sdio_enable_wide(card);
375 	if (err <= 0)
376 		return err;
377 	if (mmc_card_sdio(card))
378 		goto out;
379 
380 	if (card->scr.bus_widths & SD_SCR_BUS_WIDTH_4) {
381 		err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4);
382 		if (err) {
383 			sdio_disable_wide(card);
384 			return err;
385 		}
386 	}
387 out:
388 	mmc_set_bus_width(card->host, MMC_BUS_WIDTH_4);
389 
390 	return 0;
391 }
392 
393 
394 /*
395  * Test if the card supports high-speed mode and, if so, switch to it.
396  */
397 static int mmc_sdio_switch_hs(struct mmc_card *card, int enable)
398 {
399 	int ret;
400 	u8 speed;
401 
402 	if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED))
403 		return 0;
404 
405 	if (!card->cccr.high_speed)
406 		return 0;
407 
408 	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &speed);
409 	if (ret)
410 		return ret;
411 
412 	if (enable)
413 		speed |= SDIO_SPEED_EHS;
414 	else
415 		speed &= ~SDIO_SPEED_EHS;
416 
417 	ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_SPEED, speed, NULL);
418 	if (ret)
419 		return ret;
420 
421 	return 1;
422 }
423 
424 /*
425  * Enable SDIO/combo card's high-speed mode. Return 0/1 if [not]supported.
426  */
427 static int sdio_enable_hs(struct mmc_card *card)
428 {
429 	int ret;
430 
431 	ret = mmc_sdio_switch_hs(card, true);
432 	if (ret <= 0 || mmc_card_sdio(card))
433 		return ret;
434 
435 	ret = mmc_sd_switch_hs(card);
436 	if (ret <= 0)
437 		mmc_sdio_switch_hs(card, false);
438 
439 	return ret;
440 }
441 
442 static unsigned mmc_sdio_get_max_clock(struct mmc_card *card)
443 {
444 	unsigned max_dtr;
445 
446 	if (mmc_card_hs(card)) {
447 		/*
448 		 * The SDIO specification doesn't mention how
449 		 * the CIS transfer speed register relates to
450 		 * high-speed, but it seems that 50 MHz is
451 		 * mandatory.
452 		 */
453 		max_dtr = 50000000;
454 	} else {
455 		max_dtr = card->cis.max_dtr;
456 	}
457 
458 	if (mmc_card_sd_combo(card))
459 		max_dtr = min(max_dtr, mmc_sd_get_max_clock(card));
460 
461 	return max_dtr;
462 }
463 
464 static unsigned char host_drive_to_sdio_drive(int host_strength)
465 {
466 	switch (host_strength) {
467 	case MMC_SET_DRIVER_TYPE_A:
468 		return SDIO_DTSx_SET_TYPE_A;
469 	case MMC_SET_DRIVER_TYPE_B:
470 		return SDIO_DTSx_SET_TYPE_B;
471 	case MMC_SET_DRIVER_TYPE_C:
472 		return SDIO_DTSx_SET_TYPE_C;
473 	case MMC_SET_DRIVER_TYPE_D:
474 		return SDIO_DTSx_SET_TYPE_D;
475 	default:
476 		return SDIO_DTSx_SET_TYPE_B;
477 	}
478 }
479 
480 static void sdio_select_driver_type(struct mmc_card *card)
481 {
482 	int card_drv_type, drive_strength, drv_type;
483 	unsigned char card_strength;
484 	int err;
485 
486 	card->drive_strength = 0;
487 
488 	card_drv_type = card->sw_caps.sd3_drv_type | SD_DRIVER_TYPE_B;
489 
490 	drive_strength = mmc_select_drive_strength(card,
491 						   card->sw_caps.uhs_max_dtr,
492 						   card_drv_type, &drv_type);
493 
494 	if (drive_strength) {
495 		/* if error just use default for drive strength B */
496 		err = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_DRIVE_STRENGTH, 0,
497 				       &card_strength);
498 		if (err)
499 			return;
500 
501 		card_strength &= ~(SDIO_DRIVE_DTSx_MASK<<SDIO_DRIVE_DTSx_SHIFT);
502 		card_strength |= host_drive_to_sdio_drive(drive_strength);
503 
504 		/* if error default to drive strength B */
505 		err = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_DRIVE_STRENGTH,
506 				       card_strength, NULL);
507 		if (err)
508 			return;
509 		card->drive_strength = drive_strength;
510 	}
511 
512 	if (drv_type)
513 		mmc_set_driver_type(card->host, drv_type);
514 }
515 
516 
517 static int sdio_set_bus_speed_mode(struct mmc_card *card)
518 {
519 	unsigned int bus_speed, timing;
520 	int err;
521 	unsigned char speed;
522 	unsigned int max_rate;
523 
524 	/*
525 	 * If the host doesn't support any of the UHS-I modes, fallback on
526 	 * default speed.
527 	 */
528 	if (!mmc_host_uhs(card->host))
529 		return 0;
530 
531 	bus_speed = SDIO_SPEED_SDR12;
532 	timing = MMC_TIMING_UHS_SDR12;
533 	if ((card->host->caps & MMC_CAP_UHS_SDR104) &&
534 	    (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_SDR104)) {
535 			bus_speed = SDIO_SPEED_SDR104;
536 			timing = MMC_TIMING_UHS_SDR104;
537 			card->sw_caps.uhs_max_dtr = UHS_SDR104_MAX_DTR;
538 			card->sd_bus_speed = UHS_SDR104_BUS_SPEED;
539 	} else if ((card->host->caps & MMC_CAP_UHS_DDR50) &&
540 		   (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_DDR50)) {
541 			bus_speed = SDIO_SPEED_DDR50;
542 			timing = MMC_TIMING_UHS_DDR50;
543 			card->sw_caps.uhs_max_dtr = UHS_DDR50_MAX_DTR;
544 			card->sd_bus_speed = UHS_DDR50_BUS_SPEED;
545 	} else if ((card->host->caps & (MMC_CAP_UHS_SDR104 |
546 		    MMC_CAP_UHS_SDR50)) && (card->sw_caps.sd3_bus_mode &
547 		    SD_MODE_UHS_SDR50)) {
548 			bus_speed = SDIO_SPEED_SDR50;
549 			timing = MMC_TIMING_UHS_SDR50;
550 			card->sw_caps.uhs_max_dtr = UHS_SDR50_MAX_DTR;
551 			card->sd_bus_speed = UHS_SDR50_BUS_SPEED;
552 	} else if ((card->host->caps & (MMC_CAP_UHS_SDR104 |
553 		    MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR25)) &&
554 		   (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_SDR25)) {
555 			bus_speed = SDIO_SPEED_SDR25;
556 			timing = MMC_TIMING_UHS_SDR25;
557 			card->sw_caps.uhs_max_dtr = UHS_SDR25_MAX_DTR;
558 			card->sd_bus_speed = UHS_SDR25_BUS_SPEED;
559 	} else if ((card->host->caps & (MMC_CAP_UHS_SDR104 |
560 		    MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR25 |
561 		    MMC_CAP_UHS_SDR12)) && (card->sw_caps.sd3_bus_mode &
562 		    SD_MODE_UHS_SDR12)) {
563 			bus_speed = SDIO_SPEED_SDR12;
564 			timing = MMC_TIMING_UHS_SDR12;
565 			card->sw_caps.uhs_max_dtr = UHS_SDR12_MAX_DTR;
566 			card->sd_bus_speed = UHS_SDR12_BUS_SPEED;
567 	}
568 
569 	err = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &speed);
570 	if (err)
571 		return err;
572 
573 	speed &= ~SDIO_SPEED_BSS_MASK;
574 	speed |= bus_speed;
575 	err = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_SPEED, speed, NULL);
576 	if (err)
577 		return err;
578 
579 	max_rate = min_not_zero(card->quirk_max_rate,
580 				card->sw_caps.uhs_max_dtr);
581 
582 	mmc_set_timing(card->host, timing);
583 	mmc_set_clock(card->host, max_rate);
584 
585 	return 0;
586 }
587 
588 /*
589  * UHS-I specific initialization procedure
590  */
591 static int mmc_sdio_init_uhs_card(struct mmc_card *card)
592 {
593 	int err;
594 
595 	if (!card->scr.sda_spec3)
596 		return 0;
597 
598 	/* Switch to wider bus */
599 	err = sdio_enable_4bit_bus(card);
600 	if (err)
601 		goto out;
602 
603 	/* Set the driver strength for the card */
604 	sdio_select_driver_type(card);
605 
606 	/* Set bus speed mode of the card */
607 	err = sdio_set_bus_speed_mode(card);
608 	if (err)
609 		goto out;
610 
611 	/*
612 	 * SPI mode doesn't define CMD19 and tuning is only valid for SDR50 and
613 	 * SDR104 mode SD-cards. Note that tuning is mandatory for SDR104.
614 	 */
615 	if (!mmc_host_is_spi(card->host) &&
616 	    ((card->host->ios.timing == MMC_TIMING_UHS_SDR50) ||
617 	      (card->host->ios.timing == MMC_TIMING_UHS_SDR104)))
618 		err = mmc_execute_tuning(card);
619 out:
620 	return err;
621 }
622 
623 static int mmc_sdio_pre_init(struct mmc_host *host, u32 ocr,
624 			     struct mmc_card *card)
625 {
626 	if (card)
627 		mmc_remove_card(card);
628 
629 	/*
630 	 * Reset the card by performing the same steps that are taken by
631 	 * mmc_rescan_try_freq() and mmc_attach_sdio() during a "normal" probe.
632 	 *
633 	 * sdio_reset() is technically not needed. Having just powered up the
634 	 * hardware, it should already be in reset state. However, some
635 	 * platforms (such as SD8686 on OLPC) do not instantly cut power,
636 	 * meaning that a reset is required when restoring power soon after
637 	 * powering off. It is harmless in other cases.
638 	 *
639 	 * The CMD5 reset (mmc_send_io_op_cond()), according to the SDIO spec,
640 	 * is not necessary for non-removable cards. However, it is required
641 	 * for OLPC SD8686 (which expects a [CMD5,5,3,7] init sequence), and
642 	 * harmless in other situations.
643 	 *
644 	 */
645 
646 	sdio_reset(host);
647 	mmc_go_idle(host);
648 	mmc_send_if_cond(host, ocr);
649 	return mmc_send_io_op_cond(host, 0, NULL);
650 }
651 
652 /*
653  * Handle the detection and initialisation of a card.
654  *
655  * In the case of a resume, "oldcard" will contain the card
656  * we're trying to reinitialise.
657  */
658 static int mmc_sdio_init_card(struct mmc_host *host, u32 ocr,
659 			      struct mmc_card *oldcard)
660 {
661 	struct mmc_card *card;
662 	int err;
663 	int retries = 10;
664 	u32 rocr = 0;
665 	u32 ocr_card = ocr;
666 
667 	WARN_ON(!host->claimed);
668 
669 	/* to query card if 1.8V signalling is supported */
670 	if (mmc_host_uhs(host))
671 		ocr |= R4_18V_PRESENT;
672 
673 try_again:
674 	if (!retries) {
675 		pr_warn("%s: Skipping voltage switch\n", mmc_hostname(host));
676 		ocr &= ~R4_18V_PRESENT;
677 	}
678 
679 	/*
680 	 * Inform the card of the voltage
681 	 */
682 	err = mmc_send_io_op_cond(host, ocr, &rocr);
683 	if (err)
684 		return err;
685 
686 	/*
687 	 * For SPI, enable CRC as appropriate.
688 	 */
689 	if (mmc_host_is_spi(host)) {
690 		err = mmc_spi_set_crc(host, use_spi_crc);
691 		if (err)
692 			return err;
693 	}
694 
695 	/*
696 	 * Allocate card structure.
697 	 */
698 	card = mmc_alloc_card(host, &sdio_type);
699 	if (IS_ERR(card))
700 		return PTR_ERR(card);
701 
702 	if ((rocr & R4_MEMORY_PRESENT) &&
703 	    mmc_sd_get_cid(host, ocr & rocr, card->raw_cid, NULL) == 0) {
704 		card->type = MMC_TYPE_SD_COMBO;
705 
706 		if (oldcard && (!mmc_card_sd_combo(oldcard) ||
707 		    memcmp(card->raw_cid, oldcard->raw_cid, sizeof(card->raw_cid)) != 0)) {
708 			err = -ENOENT;
709 			goto mismatch;
710 		}
711 	} else {
712 		card->type = MMC_TYPE_SDIO;
713 
714 		if (oldcard && !mmc_card_sdio(oldcard)) {
715 			err = -ENOENT;
716 			goto mismatch;
717 		}
718 	}
719 
720 	/*
721 	 * Call the optional HC's init_card function to handle quirks.
722 	 */
723 	if (host->ops->init_card)
724 		host->ops->init_card(host, card);
725 	mmc_fixup_device(card, sdio_card_init_methods);
726 
727 	card->ocr = ocr_card;
728 
729 	/*
730 	 * If the host and card support UHS-I mode request the card
731 	 * to switch to 1.8V signaling level.  No 1.8v signalling if
732 	 * UHS mode is not enabled to maintain compatibility and some
733 	 * systems that claim 1.8v signalling in fact do not support
734 	 * it. Per SDIO spec v3, section 3.1.2, if the voltage is already
735 	 * 1.8v, the card sets S18A to 0 in the R4 response. So it will
736 	 * fails to check rocr & R4_18V_PRESENT,  but we still need to
737 	 * try to init uhs card. sdio_read_cccr will take over this task
738 	 * to make sure which speed mode should work.
739 	 */
740 	if (rocr & ocr & R4_18V_PRESENT) {
741 		err = mmc_set_uhs_voltage(host, ocr_card);
742 		if (err == -EAGAIN) {
743 			mmc_sdio_pre_init(host, ocr_card, card);
744 			retries--;
745 			goto try_again;
746 		} else if (err) {
747 			ocr &= ~R4_18V_PRESENT;
748 		}
749 	}
750 
751 	/*
752 	 * For native busses:  set card RCA and quit open drain mode.
753 	 */
754 	if (!mmc_host_is_spi(host)) {
755 		err = mmc_send_relative_addr(host, &card->rca);
756 		if (err)
757 			goto remove;
758 
759 		/*
760 		 * Update oldcard with the new RCA received from the SDIO
761 		 * device -- we're doing this so that it's updated in the
762 		 * "card" struct when oldcard overwrites that later.
763 		 */
764 		if (oldcard)
765 			oldcard->rca = card->rca;
766 	}
767 
768 	/*
769 	 * Read CSD, before selecting the card
770 	 */
771 	if (!oldcard && mmc_card_sd_combo(card)) {
772 		err = mmc_sd_get_csd(card);
773 		if (err)
774 			goto remove;
775 
776 		mmc_decode_cid(card);
777 	}
778 
779 	/*
780 	 * Select card, as all following commands rely on that.
781 	 */
782 	if (!mmc_host_is_spi(host)) {
783 		err = mmc_select_card(card);
784 		if (err)
785 			goto remove;
786 	}
787 
788 	if (card->quirks & MMC_QUIRK_NONSTD_SDIO) {
789 		/*
790 		 * This is non-standard SDIO device, meaning it doesn't
791 		 * have any CIA (Common I/O area) registers present.
792 		 * It's host's responsibility to fill cccr and cis
793 		 * structures in init_card().
794 		 */
795 		mmc_set_clock(host, card->cis.max_dtr);
796 
797 		if (card->cccr.high_speed) {
798 			mmc_set_timing(card->host, MMC_TIMING_SD_HS);
799 		}
800 
801 		if (oldcard)
802 			mmc_remove_card(card);
803 		else
804 			host->card = card;
805 
806 		return 0;
807 	}
808 
809 	/*
810 	 * Read the common registers. Note that we should try to
811 	 * validate whether UHS would work or not.
812 	 */
813 	err = sdio_read_cccr(card, ocr);
814 	if (err) {
815 		mmc_sdio_pre_init(host, ocr_card, card);
816 		if (ocr & R4_18V_PRESENT) {
817 			/* Retry init sequence, but without R4_18V_PRESENT. */
818 			retries = 0;
819 			goto try_again;
820 		}
821 		return err;
822 	}
823 
824 	/*
825 	 * Read the common CIS tuples.
826 	 */
827 	err = sdio_read_common_cis(card);
828 	if (err)
829 		goto remove;
830 
831 	if (oldcard) {
832 		if (card->cis.vendor == oldcard->cis.vendor &&
833 		    card->cis.device == oldcard->cis.device) {
834 			mmc_remove_card(card);
835 			card = oldcard;
836 		} else {
837 			err = -ENOENT;
838 			goto mismatch;
839 		}
840 	}
841 
842 	mmc_fixup_device(card, sdio_fixup_methods);
843 
844 	if (mmc_card_sd_combo(card)) {
845 		err = mmc_sd_setup_card(host, card, oldcard != NULL);
846 		/* handle as SDIO-only card if memory init failed */
847 		if (err) {
848 			mmc_go_idle(host);
849 			if (mmc_host_is_spi(host))
850 				/* should not fail, as it worked previously */
851 				mmc_spi_set_crc(host, use_spi_crc);
852 			card->type = MMC_TYPE_SDIO;
853 		} else
854 			card->dev.type = &sd_type;
855 	}
856 
857 	/*
858 	 * If needed, disconnect card detection pull-up resistor.
859 	 */
860 	err = sdio_disable_cd(card);
861 	if (err)
862 		goto remove;
863 
864 	/* Initialization sequence for UHS-I cards */
865 	/* Only if card supports 1.8v and UHS signaling */
866 	if ((ocr & R4_18V_PRESENT) && card->sw_caps.sd3_bus_mode) {
867 		err = mmc_sdio_init_uhs_card(card);
868 		if (err)
869 			goto remove;
870 	} else {
871 		/*
872 		 * Switch to high-speed (if supported).
873 		 */
874 		err = sdio_enable_hs(card);
875 		if (err > 0)
876 			mmc_set_timing(card->host, MMC_TIMING_SD_HS);
877 		else if (err)
878 			goto remove;
879 
880 		/*
881 		 * Change to the card's maximum speed.
882 		 */
883 		mmc_set_clock(host, mmc_sdio_get_max_clock(card));
884 
885 		/*
886 		 * Switch to wider bus (if supported).
887 		 */
888 		err = sdio_enable_4bit_bus(card);
889 		if (err)
890 			goto remove;
891 	}
892 
893 	if (host->caps2 & MMC_CAP2_AVOID_3_3V &&
894 	    host->ios.signal_voltage == MMC_SIGNAL_VOLTAGE_330) {
895 		pr_err("%s: Host failed to negotiate down from 3.3V\n",
896 			mmc_hostname(host));
897 		err = -EINVAL;
898 		goto remove;
899 	}
900 
901 	host->card = card;
902 	return 0;
903 
904 mismatch:
905 	pr_debug("%s: Perhaps the card was replaced\n", mmc_hostname(host));
906 remove:
907 	if (oldcard != card)
908 		mmc_remove_card(card);
909 	return err;
910 }
911 
912 static int mmc_sdio_reinit_card(struct mmc_host *host)
913 {
914 	int ret;
915 
916 	ret = mmc_sdio_pre_init(host, host->card->ocr, NULL);
917 	if (ret)
918 		return ret;
919 
920 	return mmc_sdio_init_card(host, host->card->ocr, host->card);
921 }
922 
923 /*
924  * Host is being removed. Free up the current card.
925  */
926 static void mmc_sdio_remove(struct mmc_host *host)
927 {
928 	int i;
929 
930 	for (i = 0;i < host->card->sdio_funcs;i++) {
931 		if (host->card->sdio_func[i]) {
932 			sdio_remove_func(host->card->sdio_func[i]);
933 			host->card->sdio_func[i] = NULL;
934 		}
935 	}
936 
937 	mmc_remove_card(host->card);
938 	host->card = NULL;
939 }
940 
941 /*
942  * Card detection - card is alive.
943  */
944 static int mmc_sdio_alive(struct mmc_host *host)
945 {
946 	return mmc_select_card(host->card);
947 }
948 
949 /*
950  * Card detection callback from host.
951  */
952 static void mmc_sdio_detect(struct mmc_host *host)
953 {
954 	int err;
955 
956 	/* Make sure card is powered before detecting it */
957 	if (host->caps & MMC_CAP_POWER_OFF_CARD) {
958 		err = pm_runtime_resume_and_get(&host->card->dev);
959 		if (err < 0)
960 			goto out;
961 	}
962 
963 	mmc_claim_host(host);
964 
965 	/*
966 	 * Just check if our card has been removed.
967 	 */
968 	err = _mmc_detect_card_removed(host);
969 
970 	mmc_release_host(host);
971 
972 	/*
973 	 * Tell PM core it's OK to power off the card now.
974 	 *
975 	 * The _sync variant is used in order to ensure that the card
976 	 * is left powered off in case an error occurred, and the card
977 	 * is going to be removed.
978 	 *
979 	 * Since there is no specific reason to believe a new user
980 	 * is about to show up at this point, the _sync variant is
981 	 * desirable anyway.
982 	 */
983 	if (host->caps & MMC_CAP_POWER_OFF_CARD)
984 		pm_runtime_put_sync(&host->card->dev);
985 
986 out:
987 	if (err) {
988 		mmc_sdio_remove(host);
989 
990 		mmc_claim_host(host);
991 		mmc_detach_bus(host);
992 		mmc_power_off(host);
993 		mmc_release_host(host);
994 	}
995 }
996 
997 /*
998  * SDIO pre_suspend.  We need to suspend all functions separately.
999  * Therefore all registered functions must have drivers with suspend
1000  * and resume methods.  Failing that we simply remove the whole card.
1001  */
1002 static int mmc_sdio_pre_suspend(struct mmc_host *host)
1003 {
1004 	int i;
1005 
1006 	for (i = 0; i < host->card->sdio_funcs; i++) {
1007 		struct sdio_func *func = host->card->sdio_func[i];
1008 		if (func && sdio_func_present(func) && func->dev.driver) {
1009 			const struct dev_pm_ops *pmops = func->dev.driver->pm;
1010 			if (!pmops || !pmops->suspend || !pmops->resume)
1011 				/* force removal of entire card in that case */
1012 				goto remove;
1013 		}
1014 	}
1015 
1016 	return 0;
1017 
1018 remove:
1019 	if (!mmc_card_is_removable(host)) {
1020 		dev_warn(mmc_dev(host),
1021 			 "missing suspend/resume ops for non-removable SDIO card\n");
1022 		/* Don't remove a non-removable card - we can't re-detect it. */
1023 		return 0;
1024 	}
1025 
1026 	/* Remove the SDIO card and let it be re-detected later on. */
1027 	mmc_sdio_remove(host);
1028 	mmc_claim_host(host);
1029 	mmc_detach_bus(host);
1030 	mmc_power_off(host);
1031 	mmc_release_host(host);
1032 	host->pm_flags = 0;
1033 
1034 	return 0;
1035 }
1036 
1037 /*
1038  * SDIO suspend.  Suspend all functions separately.
1039  */
1040 static int mmc_sdio_suspend(struct mmc_host *host)
1041 {
1042 	WARN_ON(host->sdio_irqs && !mmc_card_keep_power(host));
1043 
1044 	/* Prevent processing of SDIO IRQs in suspended state. */
1045 	mmc_card_set_suspended(host->card);
1046 	cancel_work_sync(&host->sdio_irq_work);
1047 
1048 	mmc_claim_host(host);
1049 
1050 	if (mmc_card_keep_power(host) && mmc_card_wake_sdio_irq(host))
1051 		sdio_disable_4bit_bus(host->card);
1052 
1053 	if (!mmc_card_keep_power(host)) {
1054 		mmc_power_off(host);
1055 	} else if (host->retune_period) {
1056 		mmc_retune_timer_stop(host);
1057 		mmc_retune_needed(host);
1058 	}
1059 
1060 	mmc_release_host(host);
1061 
1062 	return 0;
1063 }
1064 
1065 static int mmc_sdio_resume(struct mmc_host *host)
1066 {
1067 	int err = 0;
1068 
1069 	/* Basic card reinitialization. */
1070 	mmc_claim_host(host);
1071 
1072 	/*
1073 	 * Restore power and reinitialize the card when needed. Note that a
1074 	 * removable card is checked from a detect work later on in the resume
1075 	 * process.
1076 	 */
1077 	if (!mmc_card_keep_power(host)) {
1078 		mmc_power_up(host, host->card->ocr);
1079 		/*
1080 		 * Tell runtime PM core we just powered up the card,
1081 		 * since it still believes the card is powered off.
1082 		 * Note that currently runtime PM is only enabled
1083 		 * for SDIO cards that are MMC_CAP_POWER_OFF_CARD
1084 		 */
1085 		if (host->caps & MMC_CAP_POWER_OFF_CARD) {
1086 			pm_runtime_disable(&host->card->dev);
1087 			pm_runtime_set_active(&host->card->dev);
1088 			pm_runtime_enable(&host->card->dev);
1089 		}
1090 		err = mmc_sdio_reinit_card(host);
1091 	} else if (mmc_card_wake_sdio_irq(host)) {
1092 		/*
1093 		 * We may have switched to 1-bit mode during suspend,
1094 		 * need to hold retuning, because tuning only supprt
1095 		 * 4-bit mode or 8 bit mode.
1096 		 */
1097 		mmc_retune_hold_now(host);
1098 		err = sdio_enable_4bit_bus(host->card);
1099 		mmc_retune_release(host);
1100 	}
1101 
1102 	if (err)
1103 		goto out;
1104 
1105 	/* Allow SDIO IRQs to be processed again. */
1106 	mmc_card_clr_suspended(host->card);
1107 
1108 	if (host->sdio_irqs) {
1109 		if (!(host->caps2 & MMC_CAP2_SDIO_IRQ_NOTHREAD))
1110 			wake_up_process(host->sdio_irq_thread);
1111 		else if (host->caps & MMC_CAP_SDIO_IRQ)
1112 			schedule_work(&host->sdio_irq_work);
1113 	}
1114 
1115 out:
1116 	mmc_release_host(host);
1117 
1118 	host->pm_flags &= ~MMC_PM_KEEP_POWER;
1119 	return err;
1120 }
1121 
1122 static int mmc_sdio_runtime_suspend(struct mmc_host *host)
1123 {
1124 	/* No references to the card, cut the power to it. */
1125 	mmc_claim_host(host);
1126 	mmc_power_off(host);
1127 	mmc_release_host(host);
1128 
1129 	return 0;
1130 }
1131 
1132 static int mmc_sdio_runtime_resume(struct mmc_host *host)
1133 {
1134 	int ret;
1135 
1136 	/* Restore power and re-initialize. */
1137 	mmc_claim_host(host);
1138 	mmc_power_up(host, host->card->ocr);
1139 	ret = mmc_sdio_reinit_card(host);
1140 	mmc_release_host(host);
1141 
1142 	return ret;
1143 }
1144 
1145 /*
1146  * SDIO HW reset
1147  *
1148  * Returns 0 if the HW reset was executed synchronously, returns 1 if the HW
1149  * reset was asynchronously scheduled, else a negative error code.
1150  */
1151 static int mmc_sdio_hw_reset(struct mmc_host *host)
1152 {
1153 	struct mmc_card *card = host->card;
1154 
1155 	/*
1156 	 * In case the card is shared among multiple func drivers, reset the
1157 	 * card through a rescan work. In this way it will be removed and
1158 	 * re-detected, thus all func drivers becomes informed about it.
1159 	 */
1160 	if (atomic_read(&card->sdio_funcs_probed) > 1) {
1161 		if (mmc_card_removed(card))
1162 			return 1;
1163 		host->rescan_entered = 0;
1164 		mmc_card_set_removed(card);
1165 		_mmc_detect_change(host, 0, false);
1166 		return 1;
1167 	}
1168 
1169 	/*
1170 	 * A single func driver has been probed, then let's skip the heavy
1171 	 * hotplug dance above and execute the reset immediately.
1172 	 */
1173 	mmc_power_cycle(host, card->ocr);
1174 	return mmc_sdio_reinit_card(host);
1175 }
1176 
1177 static int mmc_sdio_sw_reset(struct mmc_host *host)
1178 {
1179 	mmc_set_clock(host, host->f_init);
1180 	sdio_reset(host);
1181 	mmc_go_idle(host);
1182 
1183 	mmc_set_initial_state(host);
1184 	mmc_set_initial_signal_voltage(host);
1185 
1186 	return mmc_sdio_reinit_card(host);
1187 }
1188 
1189 static const struct mmc_bus_ops mmc_sdio_ops = {
1190 	.remove = mmc_sdio_remove,
1191 	.detect = mmc_sdio_detect,
1192 	.pre_suspend = mmc_sdio_pre_suspend,
1193 	.suspend = mmc_sdio_suspend,
1194 	.resume = mmc_sdio_resume,
1195 	.runtime_suspend = mmc_sdio_runtime_suspend,
1196 	.runtime_resume = mmc_sdio_runtime_resume,
1197 	.alive = mmc_sdio_alive,
1198 	.hw_reset = mmc_sdio_hw_reset,
1199 	.sw_reset = mmc_sdio_sw_reset,
1200 };
1201 
1202 
1203 /*
1204  * Starting point for SDIO card init.
1205  */
1206 int mmc_attach_sdio(struct mmc_host *host)
1207 {
1208 	int err, i, funcs;
1209 	u32 ocr, rocr;
1210 	struct mmc_card *card;
1211 
1212 	WARN_ON(!host->claimed);
1213 
1214 	err = mmc_send_io_op_cond(host, 0, &ocr);
1215 	if (err)
1216 		return err;
1217 
1218 	mmc_attach_bus(host, &mmc_sdio_ops);
1219 	if (host->ocr_avail_sdio)
1220 		host->ocr_avail = host->ocr_avail_sdio;
1221 
1222 
1223 	rocr = mmc_select_voltage(host, ocr);
1224 
1225 	/*
1226 	 * Can we support the voltage(s) of the card(s)?
1227 	 */
1228 	if (!rocr) {
1229 		err = -EINVAL;
1230 		goto err;
1231 	}
1232 
1233 	/*
1234 	 * Detect and init the card.
1235 	 */
1236 	err = mmc_sdio_init_card(host, rocr, NULL);
1237 	if (err)
1238 		goto err;
1239 
1240 	card = host->card;
1241 
1242 	/*
1243 	 * Enable runtime PM only if supported by host+card+board
1244 	 */
1245 	if (host->caps & MMC_CAP_POWER_OFF_CARD) {
1246 		/*
1247 		 * Do not allow runtime suspend until after SDIO function
1248 		 * devices are added.
1249 		 */
1250 		pm_runtime_get_noresume(&card->dev);
1251 
1252 		/*
1253 		 * Let runtime PM core know our card is active
1254 		 */
1255 		err = pm_runtime_set_active(&card->dev);
1256 		if (err)
1257 			goto remove;
1258 
1259 		/*
1260 		 * Enable runtime PM for this card
1261 		 */
1262 		pm_runtime_enable(&card->dev);
1263 	}
1264 
1265 	/*
1266 	 * The number of functions on the card is encoded inside
1267 	 * the ocr.
1268 	 */
1269 	funcs = (ocr & 0x70000000) >> 28;
1270 	card->sdio_funcs = 0;
1271 
1272 	/*
1273 	 * Initialize (but don't add) all present functions.
1274 	 */
1275 	for (i = 0; i < funcs; i++, card->sdio_funcs++) {
1276 		err = sdio_init_func(host->card, i + 1);
1277 		if (err)
1278 			goto remove;
1279 
1280 		/*
1281 		 * Enable Runtime PM for this func (if supported)
1282 		 */
1283 		if (host->caps & MMC_CAP_POWER_OFF_CARD)
1284 			pm_runtime_enable(&card->sdio_func[i]->dev);
1285 	}
1286 
1287 	/*
1288 	 * First add the card to the driver model...
1289 	 */
1290 	mmc_release_host(host);
1291 	err = mmc_add_card(host->card);
1292 	if (err)
1293 		goto remove_added;
1294 
1295 	/*
1296 	 * ...then the SDIO functions.
1297 	 */
1298 	for (i = 0;i < funcs;i++) {
1299 		err = sdio_add_func(host->card->sdio_func[i]);
1300 		if (err)
1301 			goto remove_added;
1302 	}
1303 
1304 	if (host->caps & MMC_CAP_POWER_OFF_CARD)
1305 		pm_runtime_put(&card->dev);
1306 
1307 	mmc_claim_host(host);
1308 	return 0;
1309 
1310 
1311 remove:
1312 	mmc_release_host(host);
1313 remove_added:
1314 	/*
1315 	 * The devices are being deleted so it is not necessary to disable
1316 	 * runtime PM. Similarly we also don't pm_runtime_put() the SDIO card
1317 	 * because it needs to be active to remove any function devices that
1318 	 * were probed, and after that it gets deleted.
1319 	 */
1320 	mmc_sdio_remove(host);
1321 	mmc_claim_host(host);
1322 err:
1323 	mmc_detach_bus(host);
1324 
1325 	pr_err("%s: error %d whilst initialising SDIO card\n",
1326 		mmc_hostname(host), err);
1327 
1328 	return err;
1329 }
1330 
1331