xref: /openbmc/linux/drivers/mmc/core/sd.c (revision bc5aa3a0)
1 /*
2  *  linux/drivers/mmc/core/sd.c
3  *
4  *  Copyright (C) 2003-2004 Russell King, All Rights Reserved.
5  *  SD support Copyright (C) 2004 Ian Molton, All Rights Reserved.
6  *  Copyright (C) 2005-2007 Pierre Ossman, All Rights Reserved.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <linux/err.h>
14 #include <linux/sizes.h>
15 #include <linux/slab.h>
16 #include <linux/stat.h>
17 #include <linux/pm_runtime.h>
18 
19 #include <linux/mmc/host.h>
20 #include <linux/mmc/card.h>
21 #include <linux/mmc/mmc.h>
22 #include <linux/mmc/sd.h>
23 
24 #include "core.h"
25 #include "bus.h"
26 #include "mmc_ops.h"
27 #include "sd.h"
28 #include "sd_ops.h"
29 
30 static const unsigned int tran_exp[] = {
31 	10000,		100000,		1000000,	10000000,
32 	0,		0,		0,		0
33 };
34 
35 static const unsigned char tran_mant[] = {
36 	0,	10,	12,	13,	15,	20,	25,	30,
37 	35,	40,	45,	50,	55,	60,	70,	80,
38 };
39 
40 static const unsigned int tacc_exp[] = {
41 	1,	10,	100,	1000,	10000,	100000,	1000000, 10000000,
42 };
43 
44 static const unsigned int tacc_mant[] = {
45 	0,	10,	12,	13,	15,	20,	25,	30,
46 	35,	40,	45,	50,	55,	60,	70,	80,
47 };
48 
49 static const unsigned int sd_au_size[] = {
50 	0,		SZ_16K / 512,		SZ_32K / 512,	SZ_64K / 512,
51 	SZ_128K / 512,	SZ_256K / 512,		SZ_512K / 512,	SZ_1M / 512,
52 	SZ_2M / 512,	SZ_4M / 512,		SZ_8M / 512,	(SZ_8M + SZ_4M) / 512,
53 	SZ_16M / 512,	(SZ_16M + SZ_8M) / 512,	SZ_32M / 512,	SZ_64M / 512,
54 };
55 
56 #define UNSTUFF_BITS(resp,start,size)					\
57 	({								\
58 		const int __size = size;				\
59 		const u32 __mask = (__size < 32 ? 1 << __size : 0) - 1;	\
60 		const int __off = 3 - ((start) / 32);			\
61 		const int __shft = (start) & 31;			\
62 		u32 __res;						\
63 									\
64 		__res = resp[__off] >> __shft;				\
65 		if (__size + __shft > 32)				\
66 			__res |= resp[__off-1] << ((32 - __shft) % 32);	\
67 		__res & __mask;						\
68 	})
69 
70 /*
71  * Given the decoded CSD structure, decode the raw CID to our CID structure.
72  */
73 void mmc_decode_cid(struct mmc_card *card)
74 {
75 	u32 *resp = card->raw_cid;
76 
77 	/*
78 	 * SD doesn't currently have a version field so we will
79 	 * have to assume we can parse this.
80 	 */
81 	card->cid.manfid		= UNSTUFF_BITS(resp, 120, 8);
82 	card->cid.oemid			= UNSTUFF_BITS(resp, 104, 16);
83 	card->cid.prod_name[0]		= UNSTUFF_BITS(resp, 96, 8);
84 	card->cid.prod_name[1]		= UNSTUFF_BITS(resp, 88, 8);
85 	card->cid.prod_name[2]		= UNSTUFF_BITS(resp, 80, 8);
86 	card->cid.prod_name[3]		= UNSTUFF_BITS(resp, 72, 8);
87 	card->cid.prod_name[4]		= UNSTUFF_BITS(resp, 64, 8);
88 	card->cid.hwrev			= UNSTUFF_BITS(resp, 60, 4);
89 	card->cid.fwrev			= UNSTUFF_BITS(resp, 56, 4);
90 	card->cid.serial		= UNSTUFF_BITS(resp, 24, 32);
91 	card->cid.year			= UNSTUFF_BITS(resp, 12, 8);
92 	card->cid.month			= UNSTUFF_BITS(resp, 8, 4);
93 
94 	card->cid.year += 2000; /* SD cards year offset */
95 }
96 
97 /*
98  * Given a 128-bit response, decode to our card CSD structure.
99  */
100 static int mmc_decode_csd(struct mmc_card *card)
101 {
102 	struct mmc_csd *csd = &card->csd;
103 	unsigned int e, m, csd_struct;
104 	u32 *resp = card->raw_csd;
105 
106 	csd_struct = UNSTUFF_BITS(resp, 126, 2);
107 
108 	switch (csd_struct) {
109 	case 0:
110 		m = UNSTUFF_BITS(resp, 115, 4);
111 		e = UNSTUFF_BITS(resp, 112, 3);
112 		csd->tacc_ns	 = (tacc_exp[e] * tacc_mant[m] + 9) / 10;
113 		csd->tacc_clks	 = UNSTUFF_BITS(resp, 104, 8) * 100;
114 
115 		m = UNSTUFF_BITS(resp, 99, 4);
116 		e = UNSTUFF_BITS(resp, 96, 3);
117 		csd->max_dtr	  = tran_exp[e] * tran_mant[m];
118 		csd->cmdclass	  = UNSTUFF_BITS(resp, 84, 12);
119 
120 		e = UNSTUFF_BITS(resp, 47, 3);
121 		m = UNSTUFF_BITS(resp, 62, 12);
122 		csd->capacity	  = (1 + m) << (e + 2);
123 
124 		csd->read_blkbits = UNSTUFF_BITS(resp, 80, 4);
125 		csd->read_partial = UNSTUFF_BITS(resp, 79, 1);
126 		csd->write_misalign = UNSTUFF_BITS(resp, 78, 1);
127 		csd->read_misalign = UNSTUFF_BITS(resp, 77, 1);
128 		csd->dsr_imp = UNSTUFF_BITS(resp, 76, 1);
129 		csd->r2w_factor = UNSTUFF_BITS(resp, 26, 3);
130 		csd->write_blkbits = UNSTUFF_BITS(resp, 22, 4);
131 		csd->write_partial = UNSTUFF_BITS(resp, 21, 1);
132 
133 		if (UNSTUFF_BITS(resp, 46, 1)) {
134 			csd->erase_size = 1;
135 		} else if (csd->write_blkbits >= 9) {
136 			csd->erase_size = UNSTUFF_BITS(resp, 39, 7) + 1;
137 			csd->erase_size <<= csd->write_blkbits - 9;
138 		}
139 		break;
140 	case 1:
141 		/*
142 		 * This is a block-addressed SDHC or SDXC card. Most
143 		 * interesting fields are unused and have fixed
144 		 * values. To avoid getting tripped by buggy cards,
145 		 * we assume those fixed values ourselves.
146 		 */
147 		mmc_card_set_blockaddr(card);
148 
149 		csd->tacc_ns	 = 0; /* Unused */
150 		csd->tacc_clks	 = 0; /* Unused */
151 
152 		m = UNSTUFF_BITS(resp, 99, 4);
153 		e = UNSTUFF_BITS(resp, 96, 3);
154 		csd->max_dtr	  = tran_exp[e] * tran_mant[m];
155 		csd->cmdclass	  = UNSTUFF_BITS(resp, 84, 12);
156 		csd->c_size	  = UNSTUFF_BITS(resp, 48, 22);
157 
158 		/* SDXC cards have a minimum C_SIZE of 0x00FFFF */
159 		if (csd->c_size >= 0xFFFF)
160 			mmc_card_set_ext_capacity(card);
161 
162 		m = UNSTUFF_BITS(resp, 48, 22);
163 		csd->capacity     = (1 + m) << 10;
164 
165 		csd->read_blkbits = 9;
166 		csd->read_partial = 0;
167 		csd->write_misalign = 0;
168 		csd->read_misalign = 0;
169 		csd->r2w_factor = 4; /* Unused */
170 		csd->write_blkbits = 9;
171 		csd->write_partial = 0;
172 		csd->erase_size = 1;
173 		break;
174 	default:
175 		pr_err("%s: unrecognised CSD structure version %d\n",
176 			mmc_hostname(card->host), csd_struct);
177 		return -EINVAL;
178 	}
179 
180 	card->erase_size = csd->erase_size;
181 
182 	return 0;
183 }
184 
185 /*
186  * Given a 64-bit response, decode to our card SCR structure.
187  */
188 static int mmc_decode_scr(struct mmc_card *card)
189 {
190 	struct sd_scr *scr = &card->scr;
191 	unsigned int scr_struct;
192 	u32 resp[4];
193 
194 	resp[3] = card->raw_scr[1];
195 	resp[2] = card->raw_scr[0];
196 
197 	scr_struct = UNSTUFF_BITS(resp, 60, 4);
198 	if (scr_struct != 0) {
199 		pr_err("%s: unrecognised SCR structure version %d\n",
200 			mmc_hostname(card->host), scr_struct);
201 		return -EINVAL;
202 	}
203 
204 	scr->sda_vsn = UNSTUFF_BITS(resp, 56, 4);
205 	scr->bus_widths = UNSTUFF_BITS(resp, 48, 4);
206 	if (scr->sda_vsn == SCR_SPEC_VER_2)
207 		/* Check if Physical Layer Spec v3.0 is supported */
208 		scr->sda_spec3 = UNSTUFF_BITS(resp, 47, 1);
209 
210 	if (UNSTUFF_BITS(resp, 55, 1))
211 		card->erased_byte = 0xFF;
212 	else
213 		card->erased_byte = 0x0;
214 
215 	if (scr->sda_spec3)
216 		scr->cmds = UNSTUFF_BITS(resp, 32, 2);
217 	return 0;
218 }
219 
220 /*
221  * Fetch and process SD Status register.
222  */
223 static int mmc_read_ssr(struct mmc_card *card)
224 {
225 	unsigned int au, es, et, eo;
226 	int err, i;
227 	u32 *ssr;
228 
229 	if (!(card->csd.cmdclass & CCC_APP_SPEC)) {
230 		pr_warn("%s: card lacks mandatory SD Status function\n",
231 			mmc_hostname(card->host));
232 		return 0;
233 	}
234 
235 	ssr = kmalloc(64, GFP_KERNEL);
236 	if (!ssr)
237 		return -ENOMEM;
238 
239 	err = mmc_app_sd_status(card, ssr);
240 	if (err) {
241 		pr_warn("%s: problem reading SD Status register\n",
242 			mmc_hostname(card->host));
243 		err = 0;
244 		goto out;
245 	}
246 
247 	for (i = 0; i < 16; i++)
248 		ssr[i] = be32_to_cpu(ssr[i]);
249 
250 	/*
251 	 * UNSTUFF_BITS only works with four u32s so we have to offset the
252 	 * bitfield positions accordingly.
253 	 */
254 	au = UNSTUFF_BITS(ssr, 428 - 384, 4);
255 	if (au) {
256 		if (au <= 9 || card->scr.sda_spec3) {
257 			card->ssr.au = sd_au_size[au];
258 			es = UNSTUFF_BITS(ssr, 408 - 384, 16);
259 			et = UNSTUFF_BITS(ssr, 402 - 384, 6);
260 			if (es && et) {
261 				eo = UNSTUFF_BITS(ssr, 400 - 384, 2);
262 				card->ssr.erase_timeout = (et * 1000) / es;
263 				card->ssr.erase_offset = eo * 1000;
264 			}
265 		} else {
266 			pr_warn("%s: SD Status: Invalid Allocation Unit size\n",
267 				mmc_hostname(card->host));
268 		}
269 	}
270 out:
271 	kfree(ssr);
272 	return err;
273 }
274 
275 /*
276  * Fetches and decodes switch information
277  */
278 static int mmc_read_switch(struct mmc_card *card)
279 {
280 	int err;
281 	u8 *status;
282 
283 	if (card->scr.sda_vsn < SCR_SPEC_VER_1)
284 		return 0;
285 
286 	if (!(card->csd.cmdclass & CCC_SWITCH)) {
287 		pr_warn("%s: card lacks mandatory switch function, performance might suffer\n",
288 			mmc_hostname(card->host));
289 		return 0;
290 	}
291 
292 	err = -EIO;
293 
294 	status = kmalloc(64, GFP_KERNEL);
295 	if (!status) {
296 		pr_err("%s: could not allocate a buffer for "
297 			"switch capabilities.\n",
298 			mmc_hostname(card->host));
299 		return -ENOMEM;
300 	}
301 
302 	/*
303 	 * Find out the card's support bits with a mode 0 operation.
304 	 * The argument does not matter, as the support bits do not
305 	 * change with the arguments.
306 	 */
307 	err = mmc_sd_switch(card, 0, 0, 0, status);
308 	if (err) {
309 		/*
310 		 * If the host or the card can't do the switch,
311 		 * fail more gracefully.
312 		 */
313 		if (err != -EINVAL && err != -ENOSYS && err != -EFAULT)
314 			goto out;
315 
316 		pr_warn("%s: problem reading Bus Speed modes\n",
317 			mmc_hostname(card->host));
318 		err = 0;
319 
320 		goto out;
321 	}
322 
323 	if (status[13] & SD_MODE_HIGH_SPEED)
324 		card->sw_caps.hs_max_dtr = HIGH_SPEED_MAX_DTR;
325 
326 	if (card->scr.sda_spec3) {
327 		card->sw_caps.sd3_bus_mode = status[13];
328 		/* Driver Strengths supported by the card */
329 		card->sw_caps.sd3_drv_type = status[9];
330 		card->sw_caps.sd3_curr_limit = status[7] | status[6] << 8;
331 	}
332 
333 out:
334 	kfree(status);
335 
336 	return err;
337 }
338 
339 /*
340  * Test if the card supports high-speed mode and, if so, switch to it.
341  */
342 int mmc_sd_switch_hs(struct mmc_card *card)
343 {
344 	int err;
345 	u8 *status;
346 
347 	if (card->scr.sda_vsn < SCR_SPEC_VER_1)
348 		return 0;
349 
350 	if (!(card->csd.cmdclass & CCC_SWITCH))
351 		return 0;
352 
353 	if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED))
354 		return 0;
355 
356 	if (card->sw_caps.hs_max_dtr == 0)
357 		return 0;
358 
359 	status = kmalloc(64, GFP_KERNEL);
360 	if (!status) {
361 		pr_err("%s: could not allocate a buffer for "
362 			"switch capabilities.\n", mmc_hostname(card->host));
363 		return -ENOMEM;
364 	}
365 
366 	err = mmc_sd_switch(card, 1, 0, 1, status);
367 	if (err)
368 		goto out;
369 
370 	if ((status[16] & 0xF) != 1) {
371 		pr_warn("%s: Problem switching card into high-speed mode!\n",
372 			mmc_hostname(card->host));
373 		err = 0;
374 	} else {
375 		err = 1;
376 	}
377 
378 out:
379 	kfree(status);
380 
381 	return err;
382 }
383 
384 static int sd_select_driver_type(struct mmc_card *card, u8 *status)
385 {
386 	int card_drv_type, drive_strength, drv_type;
387 	int err;
388 
389 	card->drive_strength = 0;
390 
391 	card_drv_type = card->sw_caps.sd3_drv_type | SD_DRIVER_TYPE_B;
392 
393 	drive_strength = mmc_select_drive_strength(card,
394 						   card->sw_caps.uhs_max_dtr,
395 						   card_drv_type, &drv_type);
396 
397 	if (drive_strength) {
398 		err = mmc_sd_switch(card, 1, 2, drive_strength, status);
399 		if (err)
400 			return err;
401 		if ((status[15] & 0xF) != drive_strength) {
402 			pr_warn("%s: Problem setting drive strength!\n",
403 				mmc_hostname(card->host));
404 			return 0;
405 		}
406 		card->drive_strength = drive_strength;
407 	}
408 
409 	if (drv_type)
410 		mmc_set_driver_type(card->host, drv_type);
411 
412 	return 0;
413 }
414 
415 static void sd_update_bus_speed_mode(struct mmc_card *card)
416 {
417 	/*
418 	 * If the host doesn't support any of the UHS-I modes, fallback on
419 	 * default speed.
420 	 */
421 	if (!mmc_host_uhs(card->host)) {
422 		card->sd_bus_speed = 0;
423 		return;
424 	}
425 
426 	if ((card->host->caps & MMC_CAP_UHS_SDR104) &&
427 	    (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_SDR104)) {
428 			card->sd_bus_speed = UHS_SDR104_BUS_SPEED;
429 	} else if ((card->host->caps & MMC_CAP_UHS_DDR50) &&
430 		   (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_DDR50)) {
431 			card->sd_bus_speed = UHS_DDR50_BUS_SPEED;
432 	} else if ((card->host->caps & (MMC_CAP_UHS_SDR104 |
433 		    MMC_CAP_UHS_SDR50)) && (card->sw_caps.sd3_bus_mode &
434 		    SD_MODE_UHS_SDR50)) {
435 			card->sd_bus_speed = UHS_SDR50_BUS_SPEED;
436 	} else if ((card->host->caps & (MMC_CAP_UHS_SDR104 |
437 		    MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR25)) &&
438 		   (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_SDR25)) {
439 			card->sd_bus_speed = UHS_SDR25_BUS_SPEED;
440 	} else if ((card->host->caps & (MMC_CAP_UHS_SDR104 |
441 		    MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR25 |
442 		    MMC_CAP_UHS_SDR12)) && (card->sw_caps.sd3_bus_mode &
443 		    SD_MODE_UHS_SDR12)) {
444 			card->sd_bus_speed = UHS_SDR12_BUS_SPEED;
445 	}
446 }
447 
448 static int sd_set_bus_speed_mode(struct mmc_card *card, u8 *status)
449 {
450 	int err;
451 	unsigned int timing = 0;
452 
453 	switch (card->sd_bus_speed) {
454 	case UHS_SDR104_BUS_SPEED:
455 		timing = MMC_TIMING_UHS_SDR104;
456 		card->sw_caps.uhs_max_dtr = UHS_SDR104_MAX_DTR;
457 		break;
458 	case UHS_DDR50_BUS_SPEED:
459 		timing = MMC_TIMING_UHS_DDR50;
460 		card->sw_caps.uhs_max_dtr = UHS_DDR50_MAX_DTR;
461 		break;
462 	case UHS_SDR50_BUS_SPEED:
463 		timing = MMC_TIMING_UHS_SDR50;
464 		card->sw_caps.uhs_max_dtr = UHS_SDR50_MAX_DTR;
465 		break;
466 	case UHS_SDR25_BUS_SPEED:
467 		timing = MMC_TIMING_UHS_SDR25;
468 		card->sw_caps.uhs_max_dtr = UHS_SDR25_MAX_DTR;
469 		break;
470 	case UHS_SDR12_BUS_SPEED:
471 		timing = MMC_TIMING_UHS_SDR12;
472 		card->sw_caps.uhs_max_dtr = UHS_SDR12_MAX_DTR;
473 		break;
474 	default:
475 		return 0;
476 	}
477 
478 	err = mmc_sd_switch(card, 1, 0, card->sd_bus_speed, status);
479 	if (err)
480 		return err;
481 
482 	if ((status[16] & 0xF) != card->sd_bus_speed)
483 		pr_warn("%s: Problem setting bus speed mode!\n",
484 			mmc_hostname(card->host));
485 	else {
486 		mmc_set_timing(card->host, timing);
487 		mmc_set_clock(card->host, card->sw_caps.uhs_max_dtr);
488 	}
489 
490 	return 0;
491 }
492 
493 /* Get host's max current setting at its current voltage */
494 static u32 sd_get_host_max_current(struct mmc_host *host)
495 {
496 	u32 voltage, max_current;
497 
498 	voltage = 1 << host->ios.vdd;
499 	switch (voltage) {
500 	case MMC_VDD_165_195:
501 		max_current = host->max_current_180;
502 		break;
503 	case MMC_VDD_29_30:
504 	case MMC_VDD_30_31:
505 		max_current = host->max_current_300;
506 		break;
507 	case MMC_VDD_32_33:
508 	case MMC_VDD_33_34:
509 		max_current = host->max_current_330;
510 		break;
511 	default:
512 		max_current = 0;
513 	}
514 
515 	return max_current;
516 }
517 
518 static int sd_set_current_limit(struct mmc_card *card, u8 *status)
519 {
520 	int current_limit = SD_SET_CURRENT_NO_CHANGE;
521 	int err;
522 	u32 max_current;
523 
524 	/*
525 	 * Current limit switch is only defined for SDR50, SDR104, and DDR50
526 	 * bus speed modes. For other bus speed modes, we do not change the
527 	 * current limit.
528 	 */
529 	if ((card->sd_bus_speed != UHS_SDR50_BUS_SPEED) &&
530 	    (card->sd_bus_speed != UHS_SDR104_BUS_SPEED) &&
531 	    (card->sd_bus_speed != UHS_DDR50_BUS_SPEED))
532 		return 0;
533 
534 	/*
535 	 * Host has different current capabilities when operating at
536 	 * different voltages, so find out its max current first.
537 	 */
538 	max_current = sd_get_host_max_current(card->host);
539 
540 	/*
541 	 * We only check host's capability here, if we set a limit that is
542 	 * higher than the card's maximum current, the card will be using its
543 	 * maximum current, e.g. if the card's maximum current is 300ma, and
544 	 * when we set current limit to 200ma, the card will draw 200ma, and
545 	 * when we set current limit to 400/600/800ma, the card will draw its
546 	 * maximum 300ma from the host.
547 	 *
548 	 * The above is incorrect: if we try to set a current limit that is
549 	 * not supported by the card, the card can rightfully error out the
550 	 * attempt, and remain at the default current limit.  This results
551 	 * in a 300mA card being limited to 200mA even though the host
552 	 * supports 800mA. Failures seen with SanDisk 8GB UHS cards with
553 	 * an iMX6 host. --rmk
554 	 */
555 	if (max_current >= 800 &&
556 	    card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_800)
557 		current_limit = SD_SET_CURRENT_LIMIT_800;
558 	else if (max_current >= 600 &&
559 		 card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_600)
560 		current_limit = SD_SET_CURRENT_LIMIT_600;
561 	else if (max_current >= 400 &&
562 		 card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_400)
563 		current_limit = SD_SET_CURRENT_LIMIT_400;
564 	else if (max_current >= 200 &&
565 		 card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_200)
566 		current_limit = SD_SET_CURRENT_LIMIT_200;
567 
568 	if (current_limit != SD_SET_CURRENT_NO_CHANGE) {
569 		err = mmc_sd_switch(card, 1, 3, current_limit, status);
570 		if (err)
571 			return err;
572 
573 		if (((status[15] >> 4) & 0x0F) != current_limit)
574 			pr_warn("%s: Problem setting current limit!\n",
575 				mmc_hostname(card->host));
576 
577 	}
578 
579 	return 0;
580 }
581 
582 /*
583  * UHS-I specific initialization procedure
584  */
585 static int mmc_sd_init_uhs_card(struct mmc_card *card)
586 {
587 	int err;
588 	u8 *status;
589 
590 	if (!card->scr.sda_spec3)
591 		return 0;
592 
593 	if (!(card->csd.cmdclass & CCC_SWITCH))
594 		return 0;
595 
596 	status = kmalloc(64, GFP_KERNEL);
597 	if (!status) {
598 		pr_err("%s: could not allocate a buffer for "
599 			"switch capabilities.\n", mmc_hostname(card->host));
600 		return -ENOMEM;
601 	}
602 
603 	/* Set 4-bit bus width */
604 	if ((card->host->caps & MMC_CAP_4_BIT_DATA) &&
605 	    (card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) {
606 		err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4);
607 		if (err)
608 			goto out;
609 
610 		mmc_set_bus_width(card->host, MMC_BUS_WIDTH_4);
611 	}
612 
613 	/*
614 	 * Select the bus speed mode depending on host
615 	 * and card capability.
616 	 */
617 	sd_update_bus_speed_mode(card);
618 
619 	/* Set the driver strength for the card */
620 	err = sd_select_driver_type(card, status);
621 	if (err)
622 		goto out;
623 
624 	/* Set current limit for the card */
625 	err = sd_set_current_limit(card, status);
626 	if (err)
627 		goto out;
628 
629 	/* Set bus speed mode of the card */
630 	err = sd_set_bus_speed_mode(card, status);
631 	if (err)
632 		goto out;
633 
634 	/*
635 	 * SPI mode doesn't define CMD19 and tuning is only valid for SDR50 and
636 	 * SDR104 mode SD-cards. Note that tuning is mandatory for SDR104.
637 	 */
638 	if (!mmc_host_is_spi(card->host) &&
639 		(card->host->ios.timing == MMC_TIMING_UHS_SDR50 ||
640 		 card->host->ios.timing == MMC_TIMING_UHS_DDR50 ||
641 		 card->host->ios.timing == MMC_TIMING_UHS_SDR104)) {
642 		err = mmc_execute_tuning(card);
643 
644 		/*
645 		 * As SD Specifications Part1 Physical Layer Specification
646 		 * Version 3.01 says, CMD19 tuning is available for unlocked
647 		 * cards in transfer state of 1.8V signaling mode. The small
648 		 * difference between v3.00 and 3.01 spec means that CMD19
649 		 * tuning is also available for DDR50 mode.
650 		 */
651 		if (err && card->host->ios.timing == MMC_TIMING_UHS_DDR50) {
652 			pr_warn("%s: ddr50 tuning failed\n",
653 				mmc_hostname(card->host));
654 			err = 0;
655 		}
656 	}
657 
658 out:
659 	kfree(status);
660 
661 	return err;
662 }
663 
664 MMC_DEV_ATTR(cid, "%08x%08x%08x%08x\n", card->raw_cid[0], card->raw_cid[1],
665 	card->raw_cid[2], card->raw_cid[3]);
666 MMC_DEV_ATTR(csd, "%08x%08x%08x%08x\n", card->raw_csd[0], card->raw_csd[1],
667 	card->raw_csd[2], card->raw_csd[3]);
668 MMC_DEV_ATTR(scr, "%08x%08x\n", card->raw_scr[0], card->raw_scr[1]);
669 MMC_DEV_ATTR(date, "%02d/%04d\n", card->cid.month, card->cid.year);
670 MMC_DEV_ATTR(erase_size, "%u\n", card->erase_size << 9);
671 MMC_DEV_ATTR(preferred_erase_size, "%u\n", card->pref_erase << 9);
672 MMC_DEV_ATTR(fwrev, "0x%x\n", card->cid.fwrev);
673 MMC_DEV_ATTR(hwrev, "0x%x\n", card->cid.hwrev);
674 MMC_DEV_ATTR(manfid, "0x%06x\n", card->cid.manfid);
675 MMC_DEV_ATTR(name, "%s\n", card->cid.prod_name);
676 MMC_DEV_ATTR(oemid, "0x%04x\n", card->cid.oemid);
677 MMC_DEV_ATTR(serial, "0x%08x\n", card->cid.serial);
678 MMC_DEV_ATTR(ocr, "%08x\n", card->ocr);
679 
680 
681 static ssize_t mmc_dsr_show(struct device *dev,
682                            struct device_attribute *attr,
683                            char *buf)
684 {
685        struct mmc_card *card = mmc_dev_to_card(dev);
686        struct mmc_host *host = card->host;
687 
688        if (card->csd.dsr_imp && host->dsr_req)
689                return sprintf(buf, "0x%x\n", host->dsr);
690        else
691                /* return default DSR value */
692                return sprintf(buf, "0x%x\n", 0x404);
693 }
694 
695 static DEVICE_ATTR(dsr, S_IRUGO, mmc_dsr_show, NULL);
696 
697 static struct attribute *sd_std_attrs[] = {
698 	&dev_attr_cid.attr,
699 	&dev_attr_csd.attr,
700 	&dev_attr_scr.attr,
701 	&dev_attr_date.attr,
702 	&dev_attr_erase_size.attr,
703 	&dev_attr_preferred_erase_size.attr,
704 	&dev_attr_fwrev.attr,
705 	&dev_attr_hwrev.attr,
706 	&dev_attr_manfid.attr,
707 	&dev_attr_name.attr,
708 	&dev_attr_oemid.attr,
709 	&dev_attr_serial.attr,
710 	&dev_attr_ocr.attr,
711 	&dev_attr_dsr.attr,
712 	NULL,
713 };
714 ATTRIBUTE_GROUPS(sd_std);
715 
716 struct device_type sd_type = {
717 	.groups = sd_std_groups,
718 };
719 
720 /*
721  * Fetch CID from card.
722  */
723 int mmc_sd_get_cid(struct mmc_host *host, u32 ocr, u32 *cid, u32 *rocr)
724 {
725 	int err;
726 	u32 max_current;
727 	int retries = 10;
728 	u32 pocr = ocr;
729 
730 try_again:
731 	if (!retries) {
732 		ocr &= ~SD_OCR_S18R;
733 		pr_warn("%s: Skipping voltage switch\n", mmc_hostname(host));
734 	}
735 
736 	/*
737 	 * Since we're changing the OCR value, we seem to
738 	 * need to tell some cards to go back to the idle
739 	 * state.  We wait 1ms to give cards time to
740 	 * respond.
741 	 */
742 	mmc_go_idle(host);
743 
744 	/*
745 	 * If SD_SEND_IF_COND indicates an SD 2.0
746 	 * compliant card and we should set bit 30
747 	 * of the ocr to indicate that we can handle
748 	 * block-addressed SDHC cards.
749 	 */
750 	err = mmc_send_if_cond(host, ocr);
751 	if (!err)
752 		ocr |= SD_OCR_CCS;
753 
754 	/*
755 	 * If the host supports one of UHS-I modes, request the card
756 	 * to switch to 1.8V signaling level. If the card has failed
757 	 * repeatedly to switch however, skip this.
758 	 */
759 	if (retries && mmc_host_uhs(host))
760 		ocr |= SD_OCR_S18R;
761 
762 	/*
763 	 * If the host can supply more than 150mA at current voltage,
764 	 * XPC should be set to 1.
765 	 */
766 	max_current = sd_get_host_max_current(host);
767 	if (max_current > 150)
768 		ocr |= SD_OCR_XPC;
769 
770 	err = mmc_send_app_op_cond(host, ocr, rocr);
771 	if (err)
772 		return err;
773 
774 	/*
775 	 * In case CCS and S18A in the response is set, start Signal Voltage
776 	 * Switch procedure. SPI mode doesn't support CMD11.
777 	 */
778 	if (!mmc_host_is_spi(host) && rocr &&
779 	   ((*rocr & 0x41000000) == 0x41000000)) {
780 		err = mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180,
781 					pocr);
782 		if (err == -EAGAIN) {
783 			retries--;
784 			goto try_again;
785 		} else if (err) {
786 			retries = 0;
787 			goto try_again;
788 		}
789 	}
790 
791 	if (mmc_host_is_spi(host))
792 		err = mmc_send_cid(host, cid);
793 	else
794 		err = mmc_all_send_cid(host, cid);
795 
796 	return err;
797 }
798 
799 int mmc_sd_get_csd(struct mmc_host *host, struct mmc_card *card)
800 {
801 	int err;
802 
803 	/*
804 	 * Fetch CSD from card.
805 	 */
806 	err = mmc_send_csd(card, card->raw_csd);
807 	if (err)
808 		return err;
809 
810 	err = mmc_decode_csd(card);
811 	if (err)
812 		return err;
813 
814 	return 0;
815 }
816 
817 static int mmc_sd_get_ro(struct mmc_host *host)
818 {
819 	int ro;
820 
821 	/*
822 	 * Some systems don't feature a write-protect pin and don't need one.
823 	 * E.g. because they only have micro-SD card slot. For those systems
824 	 * assume that the SD card is always read-write.
825 	 */
826 	if (host->caps2 & MMC_CAP2_NO_WRITE_PROTECT)
827 		return 0;
828 
829 	if (!host->ops->get_ro)
830 		return -1;
831 
832 	ro = host->ops->get_ro(host);
833 
834 	return ro;
835 }
836 
837 int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card,
838 	bool reinit)
839 {
840 	int err;
841 
842 	if (!reinit) {
843 		/*
844 		 * Fetch SCR from card.
845 		 */
846 		err = mmc_app_send_scr(card, card->raw_scr);
847 		if (err)
848 			return err;
849 
850 		err = mmc_decode_scr(card);
851 		if (err)
852 			return err;
853 
854 		/*
855 		 * Fetch and process SD Status register.
856 		 */
857 		err = mmc_read_ssr(card);
858 		if (err)
859 			return err;
860 
861 		/* Erase init depends on CSD and SSR */
862 		mmc_init_erase(card);
863 
864 		/*
865 		 * Fetch switch information from card.
866 		 */
867 		err = mmc_read_switch(card);
868 		if (err)
869 			return err;
870 	}
871 
872 	/*
873 	 * For SPI, enable CRC as appropriate.
874 	 * This CRC enable is located AFTER the reading of the
875 	 * card registers because some SDHC cards are not able
876 	 * to provide valid CRCs for non-512-byte blocks.
877 	 */
878 	if (mmc_host_is_spi(host)) {
879 		err = mmc_spi_set_crc(host, use_spi_crc);
880 		if (err)
881 			return err;
882 	}
883 
884 	/*
885 	 * Check if read-only switch is active.
886 	 */
887 	if (!reinit) {
888 		int ro = mmc_sd_get_ro(host);
889 
890 		if (ro < 0) {
891 			pr_warn("%s: host does not support reading read-only switch, assuming write-enable\n",
892 				mmc_hostname(host));
893 		} else if (ro > 0) {
894 			mmc_card_set_readonly(card);
895 		}
896 	}
897 
898 	return 0;
899 }
900 
901 unsigned mmc_sd_get_max_clock(struct mmc_card *card)
902 {
903 	unsigned max_dtr = (unsigned int)-1;
904 
905 	if (mmc_card_hs(card)) {
906 		if (max_dtr > card->sw_caps.hs_max_dtr)
907 			max_dtr = card->sw_caps.hs_max_dtr;
908 	} else if (max_dtr > card->csd.max_dtr) {
909 		max_dtr = card->csd.max_dtr;
910 	}
911 
912 	return max_dtr;
913 }
914 
915 /*
916  * Handle the detection and initialisation of a card.
917  *
918  * In the case of a resume, "oldcard" will contain the card
919  * we're trying to reinitialise.
920  */
921 static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
922 	struct mmc_card *oldcard)
923 {
924 	struct mmc_card *card;
925 	int err;
926 	u32 cid[4];
927 	u32 rocr = 0;
928 
929 	BUG_ON(!host);
930 	WARN_ON(!host->claimed);
931 
932 	err = mmc_sd_get_cid(host, ocr, cid, &rocr);
933 	if (err)
934 		return err;
935 
936 	if (oldcard) {
937 		if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0)
938 			return -ENOENT;
939 
940 		card = oldcard;
941 	} else {
942 		/*
943 		 * Allocate card structure.
944 		 */
945 		card = mmc_alloc_card(host, &sd_type);
946 		if (IS_ERR(card))
947 			return PTR_ERR(card);
948 
949 		card->ocr = ocr;
950 		card->type = MMC_TYPE_SD;
951 		memcpy(card->raw_cid, cid, sizeof(card->raw_cid));
952 	}
953 
954 	/*
955 	 * Call the optional HC's init_card function to handle quirks.
956 	 */
957 	if (host->ops->init_card)
958 		host->ops->init_card(host, card);
959 
960 	/*
961 	 * For native busses:  get card RCA and quit open drain mode.
962 	 */
963 	if (!mmc_host_is_spi(host)) {
964 		err = mmc_send_relative_addr(host, &card->rca);
965 		if (err)
966 			goto free_card;
967 	}
968 
969 	if (!oldcard) {
970 		err = mmc_sd_get_csd(host, card);
971 		if (err)
972 			goto free_card;
973 
974 		mmc_decode_cid(card);
975 	}
976 
977 	/*
978 	 * handling only for cards supporting DSR and hosts requesting
979 	 * DSR configuration
980 	 */
981 	if (card->csd.dsr_imp && host->dsr_req)
982 		mmc_set_dsr(host);
983 
984 	/*
985 	 * Select card, as all following commands rely on that.
986 	 */
987 	if (!mmc_host_is_spi(host)) {
988 		err = mmc_select_card(card);
989 		if (err)
990 			goto free_card;
991 	}
992 
993 	err = mmc_sd_setup_card(host, card, oldcard != NULL);
994 	if (err)
995 		goto free_card;
996 
997 	/* Initialization sequence for UHS-I cards */
998 	if (rocr & SD_ROCR_S18A) {
999 		err = mmc_sd_init_uhs_card(card);
1000 		if (err)
1001 			goto free_card;
1002 	} else {
1003 		/*
1004 		 * Attempt to change to high-speed (if supported)
1005 		 */
1006 		err = mmc_sd_switch_hs(card);
1007 		if (err > 0)
1008 			mmc_set_timing(card->host, MMC_TIMING_SD_HS);
1009 		else if (err)
1010 			goto free_card;
1011 
1012 		/*
1013 		 * Set bus speed.
1014 		 */
1015 		mmc_set_clock(host, mmc_sd_get_max_clock(card));
1016 
1017 		/*
1018 		 * Switch to wider bus (if supported).
1019 		 */
1020 		if ((host->caps & MMC_CAP_4_BIT_DATA) &&
1021 			(card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) {
1022 			err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4);
1023 			if (err)
1024 				goto free_card;
1025 
1026 			mmc_set_bus_width(host, MMC_BUS_WIDTH_4);
1027 		}
1028 	}
1029 
1030 	host->card = card;
1031 	return 0;
1032 
1033 free_card:
1034 	if (!oldcard)
1035 		mmc_remove_card(card);
1036 
1037 	return err;
1038 }
1039 
1040 /*
1041  * Host is being removed. Free up the current card.
1042  */
1043 static void mmc_sd_remove(struct mmc_host *host)
1044 {
1045 	BUG_ON(!host);
1046 	BUG_ON(!host->card);
1047 
1048 	mmc_remove_card(host->card);
1049 	host->card = NULL;
1050 }
1051 
1052 /*
1053  * Card detection - card is alive.
1054  */
1055 static int mmc_sd_alive(struct mmc_host *host)
1056 {
1057 	return mmc_send_status(host->card, NULL);
1058 }
1059 
1060 /*
1061  * Card detection callback from host.
1062  */
1063 static void mmc_sd_detect(struct mmc_host *host)
1064 {
1065 	int err;
1066 
1067 	BUG_ON(!host);
1068 	BUG_ON(!host->card);
1069 
1070 	mmc_get_card(host->card);
1071 
1072 	/*
1073 	 * Just check if our card has been removed.
1074 	 */
1075 	err = _mmc_detect_card_removed(host);
1076 
1077 	mmc_put_card(host->card);
1078 
1079 	if (err) {
1080 		mmc_sd_remove(host);
1081 
1082 		mmc_claim_host(host);
1083 		mmc_detach_bus(host);
1084 		mmc_power_off(host);
1085 		mmc_release_host(host);
1086 	}
1087 }
1088 
1089 static int _mmc_sd_suspend(struct mmc_host *host)
1090 {
1091 	int err = 0;
1092 
1093 	BUG_ON(!host);
1094 	BUG_ON(!host->card);
1095 
1096 	mmc_claim_host(host);
1097 
1098 	if (mmc_card_suspended(host->card))
1099 		goto out;
1100 
1101 	if (!mmc_host_is_spi(host))
1102 		err = mmc_deselect_cards(host);
1103 
1104 	if (!err) {
1105 		mmc_power_off(host);
1106 		mmc_card_set_suspended(host->card);
1107 	}
1108 
1109 out:
1110 	mmc_release_host(host);
1111 	return err;
1112 }
1113 
1114 /*
1115  * Callback for suspend
1116  */
1117 static int mmc_sd_suspend(struct mmc_host *host)
1118 {
1119 	int err;
1120 
1121 	err = _mmc_sd_suspend(host);
1122 	if (!err) {
1123 		pm_runtime_disable(&host->card->dev);
1124 		pm_runtime_set_suspended(&host->card->dev);
1125 	}
1126 
1127 	return err;
1128 }
1129 
1130 /*
1131  * This function tries to determine if the same card is still present
1132  * and, if so, restore all state to it.
1133  */
1134 static int _mmc_sd_resume(struct mmc_host *host)
1135 {
1136 	int err = 0;
1137 
1138 	BUG_ON(!host);
1139 	BUG_ON(!host->card);
1140 
1141 	mmc_claim_host(host);
1142 
1143 	if (!mmc_card_suspended(host->card))
1144 		goto out;
1145 
1146 	mmc_power_up(host, host->card->ocr);
1147 	err = mmc_sd_init_card(host, host->card->ocr, host->card);
1148 	mmc_card_clr_suspended(host->card);
1149 
1150 out:
1151 	mmc_release_host(host);
1152 	return err;
1153 }
1154 
1155 /*
1156  * Callback for resume
1157  */
1158 static int mmc_sd_resume(struct mmc_host *host)
1159 {
1160 	pm_runtime_enable(&host->card->dev);
1161 	return 0;
1162 }
1163 
1164 /*
1165  * Callback for runtime_suspend.
1166  */
1167 static int mmc_sd_runtime_suspend(struct mmc_host *host)
1168 {
1169 	int err;
1170 
1171 	if (!(host->caps & MMC_CAP_AGGRESSIVE_PM))
1172 		return 0;
1173 
1174 	err = _mmc_sd_suspend(host);
1175 	if (err)
1176 		pr_err("%s: error %d doing aggressive suspend\n",
1177 			mmc_hostname(host), err);
1178 
1179 	return err;
1180 }
1181 
1182 /*
1183  * Callback for runtime_resume.
1184  */
1185 static int mmc_sd_runtime_resume(struct mmc_host *host)
1186 {
1187 	int err;
1188 
1189 	err = _mmc_sd_resume(host);
1190 	if (err && err != -ENOMEDIUM)
1191 		pr_err("%s: error %d doing runtime resume\n",
1192 			mmc_hostname(host), err);
1193 
1194 	return 0;
1195 }
1196 
1197 static int mmc_sd_reset(struct mmc_host *host)
1198 {
1199 	mmc_power_cycle(host, host->card->ocr);
1200 	return mmc_sd_init_card(host, host->card->ocr, host->card);
1201 }
1202 
1203 static const struct mmc_bus_ops mmc_sd_ops = {
1204 	.remove = mmc_sd_remove,
1205 	.detect = mmc_sd_detect,
1206 	.runtime_suspend = mmc_sd_runtime_suspend,
1207 	.runtime_resume = mmc_sd_runtime_resume,
1208 	.suspend = mmc_sd_suspend,
1209 	.resume = mmc_sd_resume,
1210 	.alive = mmc_sd_alive,
1211 	.shutdown = mmc_sd_suspend,
1212 	.reset = mmc_sd_reset,
1213 };
1214 
1215 /*
1216  * Starting point for SD card init.
1217  */
1218 int mmc_attach_sd(struct mmc_host *host)
1219 {
1220 	int err;
1221 	u32 ocr, rocr;
1222 
1223 	BUG_ON(!host);
1224 	WARN_ON(!host->claimed);
1225 
1226 	err = mmc_send_app_op_cond(host, 0, &ocr);
1227 	if (err)
1228 		return err;
1229 
1230 	mmc_attach_bus(host, &mmc_sd_ops);
1231 	if (host->ocr_avail_sd)
1232 		host->ocr_avail = host->ocr_avail_sd;
1233 
1234 	/*
1235 	 * We need to get OCR a different way for SPI.
1236 	 */
1237 	if (mmc_host_is_spi(host)) {
1238 		mmc_go_idle(host);
1239 
1240 		err = mmc_spi_read_ocr(host, 0, &ocr);
1241 		if (err)
1242 			goto err;
1243 	}
1244 
1245 	rocr = mmc_select_voltage(host, ocr);
1246 
1247 	/*
1248 	 * Can we support the voltage(s) of the card(s)?
1249 	 */
1250 	if (!rocr) {
1251 		err = -EINVAL;
1252 		goto err;
1253 	}
1254 
1255 	/*
1256 	 * Detect and init the card.
1257 	 */
1258 	err = mmc_sd_init_card(host, rocr, NULL);
1259 	if (err)
1260 		goto err;
1261 
1262 	mmc_release_host(host);
1263 	err = mmc_add_card(host->card);
1264 	if (err)
1265 		goto remove_card;
1266 
1267 	mmc_claim_host(host);
1268 	return 0;
1269 
1270 remove_card:
1271 	mmc_remove_card(host->card);
1272 	host->card = NULL;
1273 	mmc_claim_host(host);
1274 err:
1275 	mmc_detach_bus(host);
1276 
1277 	pr_err("%s: error %d whilst initialising SD card\n",
1278 		mmc_hostname(host), err);
1279 
1280 	return err;
1281 }
1282