xref: /linux/drivers/mmc/core/sd.c (revision 3fd6c59042dbba50391e30862beac979491145fe)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/drivers/mmc/core/sd.c
4  *
5  *  Copyright (C) 2003-2004 Russell King, All Rights Reserved.
6  *  SD support Copyright (C) 2004 Ian Molton, All Rights Reserved.
7  *  Copyright (C) 2005-2007 Pierre Ossman, All Rights Reserved.
8  */
9 
10 #include <linux/err.h>
11 #include <linux/sizes.h>
12 #include <linux/slab.h>
13 #include <linux/stat.h>
14 #include <linux/pm_runtime.h>
15 #include <linux/random.h>
16 #include <linux/scatterlist.h>
17 #include <linux/sysfs.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 "card.h"
26 #include "host.h"
27 #include "bus.h"
28 #include "mmc_ops.h"
29 #include "quirks.h"
30 #include "sd.h"
31 #include "sd_ops.h"
32 
33 static const unsigned int tran_exp[] = {
34 	10000,		100000,		1000000,	10000000,
35 	0,		0,		0,		0
36 };
37 
38 static const unsigned char tran_mant[] = {
39 	0,	10,	12,	13,	15,	20,	25,	30,
40 	35,	40,	45,	50,	55,	60,	70,	80,
41 };
42 
43 static const unsigned int taac_exp[] = {
44 	1,	10,	100,	1000,	10000,	100000,	1000000, 10000000,
45 };
46 
47 static const unsigned int taac_mant[] = {
48 	0,	10,	12,	13,	15,	20,	25,	30,
49 	35,	40,	45,	50,	55,	60,	70,	80,
50 };
51 
52 static const unsigned int sd_au_size[] = {
53 	0,		SZ_16K / 512,		SZ_32K / 512,	SZ_64K / 512,
54 	SZ_128K / 512,	SZ_256K / 512,		SZ_512K / 512,	SZ_1M / 512,
55 	SZ_2M / 512,	SZ_4M / 512,		SZ_8M / 512,	(SZ_8M + SZ_4M) / 512,
56 	SZ_16M / 512,	(SZ_16M + SZ_8M) / 512,	SZ_32M / 512,	SZ_64M / 512,
57 };
58 
59 #define SD_POWEROFF_NOTIFY_TIMEOUT_MS 1000
60 #define SD_WRITE_EXTR_SINGLE_TIMEOUT_MS 1000
61 
62 struct sd_busy_data {
63 	struct mmc_card *card;
64 	u8 *reg_buf;
65 };
66 
67 /*
68  * Given the decoded CSD structure, decode the raw CID to our CID structure.
69  */
mmc_decode_cid(struct mmc_card * card)70 void mmc_decode_cid(struct mmc_card *card)
71 {
72 	u32 *resp = card->raw_cid;
73 
74 	/*
75 	 * Add the raw card ID (cid) data to the entropy pool. It doesn't
76 	 * matter that not all of it is unique, it's just bonus entropy.
77 	 */
78 	add_device_randomness(&card->raw_cid, sizeof(card->raw_cid));
79 
80 	/*
81 	 * SD doesn't currently have a version field so we will
82 	 * have to assume we can parse this.
83 	 */
84 	card->cid.manfid		= unstuff_bits(resp, 120, 8);
85 	card->cid.oemid			= unstuff_bits(resp, 104, 16);
86 	card->cid.prod_name[0]		= unstuff_bits(resp, 96, 8);
87 	card->cid.prod_name[1]		= unstuff_bits(resp, 88, 8);
88 	card->cid.prod_name[2]		= unstuff_bits(resp, 80, 8);
89 	card->cid.prod_name[3]		= unstuff_bits(resp, 72, 8);
90 	card->cid.prod_name[4]		= unstuff_bits(resp, 64, 8);
91 	card->cid.hwrev			= unstuff_bits(resp, 60, 4);
92 	card->cid.fwrev			= unstuff_bits(resp, 56, 4);
93 	card->cid.serial		= unstuff_bits(resp, 24, 32);
94 	card->cid.year			= unstuff_bits(resp, 12, 8);
95 	card->cid.month			= unstuff_bits(resp, 8, 4);
96 
97 	card->cid.year += 2000; /* SD cards year offset */
98 }
99 
100 /*
101  * Given a 128-bit response, decode to our card CSD structure.
102  */
mmc_decode_csd(struct mmc_card * card,bool is_sduc)103 static int mmc_decode_csd(struct mmc_card *card, bool is_sduc)
104 {
105 	struct mmc_csd *csd = &card->csd;
106 	unsigned int e, m, csd_struct;
107 	u32 *resp = card->raw_csd;
108 
109 	csd_struct = unstuff_bits(resp, 126, 2);
110 
111 	switch (csd_struct) {
112 	case 0:
113 		m = unstuff_bits(resp, 115, 4);
114 		e = unstuff_bits(resp, 112, 3);
115 		csd->taac_ns	 = (taac_exp[e] * taac_mant[m] + 9) / 10;
116 		csd->taac_clks	 = unstuff_bits(resp, 104, 8) * 100;
117 
118 		m = unstuff_bits(resp, 99, 4);
119 		e = unstuff_bits(resp, 96, 3);
120 		csd->max_dtr	  = tran_exp[e] * tran_mant[m];
121 		csd->cmdclass	  = unstuff_bits(resp, 84, 12);
122 
123 		e = unstuff_bits(resp, 47, 3);
124 		m = unstuff_bits(resp, 62, 12);
125 		csd->capacity	  = (1 + m) << (e + 2);
126 
127 		csd->read_blkbits = unstuff_bits(resp, 80, 4);
128 		csd->read_partial = unstuff_bits(resp, 79, 1);
129 		csd->write_misalign = unstuff_bits(resp, 78, 1);
130 		csd->read_misalign = unstuff_bits(resp, 77, 1);
131 		csd->dsr_imp = unstuff_bits(resp, 76, 1);
132 		csd->r2w_factor = unstuff_bits(resp, 26, 3);
133 		csd->write_blkbits = unstuff_bits(resp, 22, 4);
134 		csd->write_partial = unstuff_bits(resp, 21, 1);
135 
136 		if (unstuff_bits(resp, 46, 1)) {
137 			csd->erase_size = 1;
138 		} else if (csd->write_blkbits >= 9) {
139 			csd->erase_size = unstuff_bits(resp, 39, 7) + 1;
140 			csd->erase_size <<= csd->write_blkbits - 9;
141 		}
142 
143 		if (unstuff_bits(resp, 13, 1))
144 			mmc_card_set_readonly(card);
145 		break;
146 	case 1:
147 	case 2:
148 		/*
149 		 * This is a block-addressed SDHC, SDXC or SDUC card.
150 		 * Most interesting fields are unused and have fixed
151 		 * values. To avoid getting tripped by buggy cards,
152 		 * we assume those fixed values ourselves.
153 		 */
154 		mmc_card_set_blockaddr(card);
155 
156 		csd->taac_ns	 = 0; /* Unused */
157 		csd->taac_clks	 = 0; /* Unused */
158 
159 		m = unstuff_bits(resp, 99, 4);
160 		e = unstuff_bits(resp, 96, 3);
161 		csd->max_dtr	  = tran_exp[e] * tran_mant[m];
162 		csd->cmdclass	  = unstuff_bits(resp, 84, 12);
163 
164 		if (csd_struct == 1)
165 			m = unstuff_bits(resp, 48, 22);
166 		else
167 			m = unstuff_bits(resp, 48, 28);
168 		csd->c_size = m;
169 
170 		if (csd->c_size >= 0x400000 && is_sduc)
171 			mmc_card_set_ult_capacity(card);
172 		else if (csd->c_size >= 0xFFFF)
173 			mmc_card_set_ext_capacity(card);
174 
175 		csd->capacity     = (1 + (typeof(sector_t))m) << 10;
176 
177 		csd->read_blkbits = 9;
178 		csd->read_partial = 0;
179 		csd->write_misalign = 0;
180 		csd->read_misalign = 0;
181 		csd->r2w_factor = 4; /* Unused */
182 		csd->write_blkbits = 9;
183 		csd->write_partial = 0;
184 		csd->erase_size = 1;
185 
186 		if (unstuff_bits(resp, 13, 1))
187 			mmc_card_set_readonly(card);
188 		break;
189 	default:
190 		pr_err("%s: unrecognised CSD structure version %d\n",
191 			mmc_hostname(card->host), csd_struct);
192 		return -EINVAL;
193 	}
194 
195 	card->erase_size = csd->erase_size;
196 
197 	return 0;
198 }
199 
200 /*
201  * Given a 64-bit response, decode to our card SCR structure.
202  */
mmc_decode_scr(struct mmc_card * card)203 int mmc_decode_scr(struct mmc_card *card)
204 {
205 	struct sd_scr *scr = &card->scr;
206 	unsigned int scr_struct;
207 	u32 resp[4];
208 
209 	resp[3] = card->raw_scr[1];
210 	resp[2] = card->raw_scr[0];
211 
212 	scr_struct = unstuff_bits(resp, 60, 4);
213 	if (scr_struct != 0) {
214 		pr_err("%s: unrecognised SCR structure version %d\n",
215 			mmc_hostname(card->host), scr_struct);
216 		return -EINVAL;
217 	}
218 
219 	scr->sda_vsn = unstuff_bits(resp, 56, 4);
220 	scr->bus_widths = unstuff_bits(resp, 48, 4);
221 	if (scr->sda_vsn == SCR_SPEC_VER_2)
222 		/* Check if Physical Layer Spec v3.0 is supported */
223 		scr->sda_spec3 = unstuff_bits(resp, 47, 1);
224 
225 	if (scr->sda_spec3) {
226 		scr->sda_spec4 = unstuff_bits(resp, 42, 1);
227 		scr->sda_specx = unstuff_bits(resp, 38, 4);
228 	}
229 
230 	if (unstuff_bits(resp, 55, 1))
231 		card->erased_byte = 0xFF;
232 	else
233 		card->erased_byte = 0x0;
234 
235 	if (scr->sda_spec4)
236 		scr->cmds = unstuff_bits(resp, 32, 4);
237 	else if (scr->sda_spec3)
238 		scr->cmds = unstuff_bits(resp, 32, 2);
239 
240 	/* SD Spec says: any SD Card shall set at least bits 0 and 2 */
241 	if (!(scr->bus_widths & SD_SCR_BUS_WIDTH_1) ||
242 	    !(scr->bus_widths & SD_SCR_BUS_WIDTH_4)) {
243 		pr_err("%s: invalid bus width\n", mmc_hostname(card->host));
244 		return -EINVAL;
245 	}
246 
247 	return 0;
248 }
249 
250 /*
251  * Fetch and process SD Status register.
252  */
mmc_read_ssr(struct mmc_card * card)253 static int mmc_read_ssr(struct mmc_card *card)
254 {
255 	unsigned int au, es, et, eo;
256 	__be32 *raw_ssr;
257 	u32 resp[4] = {};
258 	u8 discard_support;
259 	int i;
260 
261 	if (!(card->csd.cmdclass & CCC_APP_SPEC)) {
262 		pr_warn("%s: card lacks mandatory SD Status function\n",
263 			mmc_hostname(card->host));
264 		return 0;
265 	}
266 
267 	raw_ssr = kmalloc(sizeof(card->raw_ssr), GFP_KERNEL);
268 	if (!raw_ssr)
269 		return -ENOMEM;
270 
271 	if (mmc_app_sd_status(card, raw_ssr)) {
272 		pr_warn("%s: problem reading SD Status register\n",
273 			mmc_hostname(card->host));
274 		kfree(raw_ssr);
275 		return 0;
276 	}
277 
278 	for (i = 0; i < 16; i++)
279 		card->raw_ssr[i] = be32_to_cpu(raw_ssr[i]);
280 
281 	kfree(raw_ssr);
282 
283 	/*
284 	 * unstuff_bits only works with four u32s so we have to offset the
285 	 * bitfield positions accordingly.
286 	 */
287 	au = unstuff_bits(card->raw_ssr, 428 - 384, 4);
288 	if (au) {
289 		if (au <= 9 || card->scr.sda_spec3) {
290 			card->ssr.au = sd_au_size[au];
291 			es = unstuff_bits(card->raw_ssr, 408 - 384, 16);
292 			et = unstuff_bits(card->raw_ssr, 402 - 384, 6);
293 			if (es && et) {
294 				eo = unstuff_bits(card->raw_ssr, 400 - 384, 2);
295 				card->ssr.erase_timeout = (et * 1000) / es;
296 				card->ssr.erase_offset = eo * 1000;
297 			}
298 		} else {
299 			pr_warn("%s: SD Status: Invalid Allocation Unit size\n",
300 				mmc_hostname(card->host));
301 		}
302 	}
303 
304 	/*
305 	 * starting SD5.1 discard is supported if DISCARD_SUPPORT (b313) is set
306 	 */
307 	resp[3] = card->raw_ssr[6];
308 	discard_support = unstuff_bits(resp, 313 - 288, 1);
309 	card->erase_arg = (card->scr.sda_specx && discard_support) ?
310 			    SD_DISCARD_ARG : SD_ERASE_ARG;
311 
312 	return 0;
313 }
314 
315 /*
316  * Fetches and decodes switch information
317  */
mmc_read_switch(struct mmc_card * card)318 static int mmc_read_switch(struct mmc_card *card)
319 {
320 	int err;
321 	u8 *status;
322 
323 	if (card->scr.sda_vsn < SCR_SPEC_VER_1)
324 		return 0;
325 
326 	if (!(card->csd.cmdclass & CCC_SWITCH)) {
327 		pr_warn("%s: card lacks mandatory switch function, performance might suffer\n",
328 			mmc_hostname(card->host));
329 		return 0;
330 	}
331 
332 	status = kmalloc(64, GFP_KERNEL);
333 	if (!status)
334 		return -ENOMEM;
335 
336 	/*
337 	 * Find out the card's support bits with a mode 0 operation.
338 	 * The argument does not matter, as the support bits do not
339 	 * change with the arguments.
340 	 */
341 	err = mmc_sd_switch(card, SD_SWITCH_CHECK, 0, 0, status);
342 	if (err) {
343 		/*
344 		 * If the host or the card can't do the switch,
345 		 * fail more gracefully.
346 		 */
347 		if (err != -EINVAL && err != -ENOSYS && err != -EFAULT)
348 			goto out;
349 
350 		pr_warn("%s: problem reading Bus Speed modes\n",
351 			mmc_hostname(card->host));
352 		err = 0;
353 
354 		goto out;
355 	}
356 
357 	if (status[13] & SD_MODE_HIGH_SPEED)
358 		card->sw_caps.hs_max_dtr = HIGH_SPEED_MAX_DTR;
359 
360 	if (card->scr.sda_spec3) {
361 		card->sw_caps.sd3_bus_mode = status[13];
362 		/* Driver Strengths supported by the card */
363 		card->sw_caps.sd3_drv_type = status[9];
364 		card->sw_caps.sd3_curr_limit = status[7] | status[6] << 8;
365 	}
366 
367 out:
368 	kfree(status);
369 
370 	return err;
371 }
372 
373 /*
374  * Test if the card supports high-speed mode and, if so, switch to it.
375  */
mmc_sd_switch_hs(struct mmc_card * card)376 int mmc_sd_switch_hs(struct mmc_card *card)
377 {
378 	int err;
379 	u8 *status;
380 
381 	if (card->scr.sda_vsn < SCR_SPEC_VER_1)
382 		return 0;
383 
384 	if (!(card->csd.cmdclass & CCC_SWITCH))
385 		return 0;
386 
387 	if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED))
388 		return 0;
389 
390 	if (card->sw_caps.hs_max_dtr == 0)
391 		return 0;
392 
393 	status = kmalloc(64, GFP_KERNEL);
394 	if (!status)
395 		return -ENOMEM;
396 
397 	err = mmc_sd_switch(card, SD_SWITCH_SET, 0,
398 			HIGH_SPEED_BUS_SPEED, status);
399 	if (err)
400 		goto out;
401 
402 	if ((status[16] & 0xF) != HIGH_SPEED_BUS_SPEED) {
403 		pr_warn("%s: Problem switching card into high-speed mode!\n",
404 			mmc_hostname(card->host));
405 		err = 0;
406 	} else {
407 		err = 1;
408 	}
409 
410 out:
411 	kfree(status);
412 
413 	return err;
414 }
415 
sd_select_driver_type(struct mmc_card * card,u8 * status)416 static int sd_select_driver_type(struct mmc_card *card, u8 *status)
417 {
418 	int card_drv_type, drive_strength, drv_type;
419 	int err;
420 
421 	card->drive_strength = 0;
422 
423 	card_drv_type = card->sw_caps.sd3_drv_type | SD_DRIVER_TYPE_B;
424 
425 	drive_strength = mmc_select_drive_strength(card,
426 						   card->sw_caps.uhs_max_dtr,
427 						   card_drv_type, &drv_type);
428 
429 	if (drive_strength) {
430 		err = mmc_sd_switch(card, SD_SWITCH_SET, 2,
431 				drive_strength, status);
432 		if (err)
433 			return err;
434 		if ((status[15] & 0xF) != drive_strength) {
435 			pr_warn("%s: Problem setting drive strength!\n",
436 				mmc_hostname(card->host));
437 			return 0;
438 		}
439 		card->drive_strength = drive_strength;
440 	}
441 
442 	if (drv_type)
443 		mmc_set_driver_type(card->host, drv_type);
444 
445 	return 0;
446 }
447 
sd_update_bus_speed_mode(struct mmc_card * card)448 static void sd_update_bus_speed_mode(struct mmc_card *card)
449 {
450 	/*
451 	 * If the host doesn't support any of the UHS-I modes, fallback on
452 	 * default speed.
453 	 */
454 	if (!mmc_host_uhs(card->host)) {
455 		card->sd_bus_speed = 0;
456 		return;
457 	}
458 
459 	if ((card->host->caps & MMC_CAP_UHS_SDR104) &&
460 	    (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_SDR104)) {
461 			card->sd_bus_speed = UHS_SDR104_BUS_SPEED;
462 	} else if ((card->host->caps & MMC_CAP_UHS_DDR50) &&
463 		   (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_DDR50)) {
464 			card->sd_bus_speed = UHS_DDR50_BUS_SPEED;
465 	} else if ((card->host->caps & (MMC_CAP_UHS_SDR104 |
466 		    MMC_CAP_UHS_SDR50)) && (card->sw_caps.sd3_bus_mode &
467 		    SD_MODE_UHS_SDR50)) {
468 			card->sd_bus_speed = UHS_SDR50_BUS_SPEED;
469 	} else if ((card->host->caps & (MMC_CAP_UHS_SDR104 |
470 		    MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR25)) &&
471 		   (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_SDR25)) {
472 			card->sd_bus_speed = UHS_SDR25_BUS_SPEED;
473 	} else if ((card->host->caps & (MMC_CAP_UHS_SDR104 |
474 		    MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR25 |
475 		    MMC_CAP_UHS_SDR12)) && (card->sw_caps.sd3_bus_mode &
476 		    SD_MODE_UHS_SDR12)) {
477 			card->sd_bus_speed = UHS_SDR12_BUS_SPEED;
478 	}
479 }
480 
sd_set_bus_speed_mode(struct mmc_card * card,u8 * status)481 static int sd_set_bus_speed_mode(struct mmc_card *card, u8 *status)
482 {
483 	int err;
484 	unsigned int timing = 0;
485 
486 	switch (card->sd_bus_speed) {
487 	case UHS_SDR104_BUS_SPEED:
488 		timing = MMC_TIMING_UHS_SDR104;
489 		card->sw_caps.uhs_max_dtr = UHS_SDR104_MAX_DTR;
490 		break;
491 	case UHS_DDR50_BUS_SPEED:
492 		timing = MMC_TIMING_UHS_DDR50;
493 		card->sw_caps.uhs_max_dtr = UHS_DDR50_MAX_DTR;
494 		break;
495 	case UHS_SDR50_BUS_SPEED:
496 		timing = MMC_TIMING_UHS_SDR50;
497 		card->sw_caps.uhs_max_dtr = UHS_SDR50_MAX_DTR;
498 		break;
499 	case UHS_SDR25_BUS_SPEED:
500 		timing = MMC_TIMING_UHS_SDR25;
501 		card->sw_caps.uhs_max_dtr = UHS_SDR25_MAX_DTR;
502 		break;
503 	case UHS_SDR12_BUS_SPEED:
504 		timing = MMC_TIMING_UHS_SDR12;
505 		card->sw_caps.uhs_max_dtr = UHS_SDR12_MAX_DTR;
506 		break;
507 	default:
508 		return 0;
509 	}
510 
511 	err = mmc_sd_switch(card, SD_SWITCH_SET, 0, card->sd_bus_speed, status);
512 	if (err)
513 		return err;
514 
515 	if ((status[16] & 0xF) != card->sd_bus_speed)
516 		pr_warn("%s: Problem setting bus speed mode!\n",
517 			mmc_hostname(card->host));
518 	else {
519 		mmc_set_timing(card->host, timing);
520 		mmc_set_clock(card->host, card->sw_caps.uhs_max_dtr);
521 	}
522 
523 	return 0;
524 }
525 
526 /* Get host's max current setting at its current voltage */
sd_get_host_max_current(struct mmc_host * host)527 static u32 sd_get_host_max_current(struct mmc_host *host)
528 {
529 	u32 voltage, max_current;
530 
531 	voltage = 1 << host->ios.vdd;
532 	switch (voltage) {
533 	case MMC_VDD_165_195:
534 		max_current = host->max_current_180;
535 		break;
536 	case MMC_VDD_29_30:
537 	case MMC_VDD_30_31:
538 		max_current = host->max_current_300;
539 		break;
540 	case MMC_VDD_32_33:
541 	case MMC_VDD_33_34:
542 		max_current = host->max_current_330;
543 		break;
544 	default:
545 		max_current = 0;
546 	}
547 
548 	return max_current;
549 }
550 
sd_set_current_limit(struct mmc_card * card,u8 * status)551 static int sd_set_current_limit(struct mmc_card *card, u8 *status)
552 {
553 	int current_limit = SD_SET_CURRENT_NO_CHANGE;
554 	int err;
555 	u32 max_current;
556 
557 	/*
558 	 * Current limit switch is only defined for SDR50, SDR104, and DDR50
559 	 * bus speed modes. For other bus speed modes, we do not change the
560 	 * current limit.
561 	 */
562 	if ((card->sd_bus_speed != UHS_SDR50_BUS_SPEED) &&
563 	    (card->sd_bus_speed != UHS_SDR104_BUS_SPEED) &&
564 	    (card->sd_bus_speed != UHS_DDR50_BUS_SPEED))
565 		return 0;
566 
567 	/*
568 	 * Host has different current capabilities when operating at
569 	 * different voltages, so find out its max current first.
570 	 */
571 	max_current = sd_get_host_max_current(card->host);
572 
573 	/*
574 	 * We only check host's capability here, if we set a limit that is
575 	 * higher than the card's maximum current, the card will be using its
576 	 * maximum current, e.g. if the card's maximum current is 300ma, and
577 	 * when we set current limit to 200ma, the card will draw 200ma, and
578 	 * when we set current limit to 400/600/800ma, the card will draw its
579 	 * maximum 300ma from the host.
580 	 *
581 	 * The above is incorrect: if we try to set a current limit that is
582 	 * not supported by the card, the card can rightfully error out the
583 	 * attempt, and remain at the default current limit.  This results
584 	 * in a 300mA card being limited to 200mA even though the host
585 	 * supports 800mA. Failures seen with SanDisk 8GB UHS cards with
586 	 * an iMX6 host. --rmk
587 	 */
588 	if (max_current >= 800 &&
589 	    card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_800)
590 		current_limit = SD_SET_CURRENT_LIMIT_800;
591 	else if (max_current >= 600 &&
592 		 card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_600)
593 		current_limit = SD_SET_CURRENT_LIMIT_600;
594 	else if (max_current >= 400 &&
595 		 card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_400)
596 		current_limit = SD_SET_CURRENT_LIMIT_400;
597 	else if (max_current >= 200 &&
598 		 card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_200)
599 		current_limit = SD_SET_CURRENT_LIMIT_200;
600 
601 	if (current_limit != SD_SET_CURRENT_NO_CHANGE) {
602 		err = mmc_sd_switch(card, SD_SWITCH_SET, 3,
603 				current_limit, status);
604 		if (err)
605 			return err;
606 
607 		if (((status[15] >> 4) & 0x0F) != current_limit)
608 			pr_warn("%s: Problem setting current limit!\n",
609 				mmc_hostname(card->host));
610 
611 	}
612 
613 	return 0;
614 }
615 
616 /*
617  * UHS-I specific initialization procedure
618  */
mmc_sd_init_uhs_card(struct mmc_card * card)619 static int mmc_sd_init_uhs_card(struct mmc_card *card)
620 {
621 	int err;
622 	u8 *status;
623 
624 	if (!(card->csd.cmdclass & CCC_SWITCH))
625 		return 0;
626 
627 	status = kmalloc(64, GFP_KERNEL);
628 	if (!status)
629 		return -ENOMEM;
630 
631 	/* Set 4-bit bus width */
632 	err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4);
633 	if (err)
634 		goto out;
635 
636 	mmc_set_bus_width(card->host, MMC_BUS_WIDTH_4);
637 
638 	/*
639 	 * Select the bus speed mode depending on host
640 	 * and card capability.
641 	 */
642 	sd_update_bus_speed_mode(card);
643 
644 	/* Set the driver strength for the card */
645 	err = sd_select_driver_type(card, status);
646 	if (err)
647 		goto out;
648 
649 	/* Set current limit for the card */
650 	err = sd_set_current_limit(card, status);
651 	if (err)
652 		goto out;
653 
654 	/* Set bus speed mode of the card */
655 	err = sd_set_bus_speed_mode(card, status);
656 	if (err)
657 		goto out;
658 
659 	/*
660 	 * SPI mode doesn't define CMD19 and tuning is only valid for SDR50 and
661 	 * SDR104 mode SD-cards. Note that tuning is mandatory for SDR104.
662 	 */
663 	if (!mmc_host_is_spi(card->host) &&
664 		(card->host->ios.timing == MMC_TIMING_UHS_SDR50 ||
665 		 card->host->ios.timing == MMC_TIMING_UHS_DDR50 ||
666 		 card->host->ios.timing == MMC_TIMING_UHS_SDR104)) {
667 		err = mmc_execute_tuning(card);
668 
669 		/*
670 		 * As SD Specifications Part1 Physical Layer Specification
671 		 * Version 3.01 says, CMD19 tuning is available for unlocked
672 		 * cards in transfer state of 1.8V signaling mode. The small
673 		 * difference between v3.00 and 3.01 spec means that CMD19
674 		 * tuning is also available for DDR50 mode.
675 		 */
676 		if (err && card->host->ios.timing == MMC_TIMING_UHS_DDR50) {
677 			pr_warn("%s: ddr50 tuning failed\n",
678 				mmc_hostname(card->host));
679 			err = 0;
680 		}
681 	}
682 
683 out:
684 	kfree(status);
685 
686 	return err;
687 }
688 
689 MMC_DEV_ATTR(cid, "%08x%08x%08x%08x\n", card->raw_cid[0], card->raw_cid[1],
690 	card->raw_cid[2], card->raw_cid[3]);
691 MMC_DEV_ATTR(csd, "%08x%08x%08x%08x\n", card->raw_csd[0], card->raw_csd[1],
692 	card->raw_csd[2], card->raw_csd[3]);
693 MMC_DEV_ATTR(scr, "%08x%08x\n", card->raw_scr[0], card->raw_scr[1]);
694 MMC_DEV_ATTR(ssr,
695 	"%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x\n",
696 		card->raw_ssr[0], card->raw_ssr[1], card->raw_ssr[2],
697 		card->raw_ssr[3], card->raw_ssr[4], card->raw_ssr[5],
698 		card->raw_ssr[6], card->raw_ssr[7], card->raw_ssr[8],
699 		card->raw_ssr[9], card->raw_ssr[10], card->raw_ssr[11],
700 		card->raw_ssr[12], card->raw_ssr[13], card->raw_ssr[14],
701 		card->raw_ssr[15]);
702 MMC_DEV_ATTR(date, "%02d/%04d\n", card->cid.month, card->cid.year);
703 MMC_DEV_ATTR(erase_size, "%u\n", card->erase_size << 9);
704 MMC_DEV_ATTR(preferred_erase_size, "%u\n", card->pref_erase << 9);
705 MMC_DEV_ATTR(fwrev, "0x%x\n", card->cid.fwrev);
706 MMC_DEV_ATTR(hwrev, "0x%x\n", card->cid.hwrev);
707 MMC_DEV_ATTR(manfid, "0x%06x\n", card->cid.manfid);
708 MMC_DEV_ATTR(name, "%s\n", card->cid.prod_name);
709 MMC_DEV_ATTR(oemid, "0x%04x\n", card->cid.oemid);
710 MMC_DEV_ATTR(serial, "0x%08x\n", card->cid.serial);
711 MMC_DEV_ATTR(ocr, "0x%08x\n", card->ocr);
712 MMC_DEV_ATTR(rca, "0x%04x\n", card->rca);
713 
714 
mmc_dsr_show(struct device * dev,struct device_attribute * attr,char * buf)715 static ssize_t mmc_dsr_show(struct device *dev, struct device_attribute *attr,
716 			    char *buf)
717 {
718 	struct mmc_card *card = mmc_dev_to_card(dev);
719 	struct mmc_host *host = card->host;
720 
721 	if (card->csd.dsr_imp && host->dsr_req)
722 		return sysfs_emit(buf, "0x%x\n", host->dsr);
723 	/* return default DSR value */
724 	return sysfs_emit(buf, "0x%x\n", 0x404);
725 }
726 
727 static DEVICE_ATTR(dsr, S_IRUGO, mmc_dsr_show, NULL);
728 
729 MMC_DEV_ATTR(vendor, "0x%04x\n", card->cis.vendor);
730 MMC_DEV_ATTR(device, "0x%04x\n", card->cis.device);
731 MMC_DEV_ATTR(revision, "%u.%u\n", card->major_rev, card->minor_rev);
732 
733 #define sdio_info_attr(num)									\
734 static ssize_t info##num##_show(struct device *dev, struct device_attribute *attr, char *buf)	\
735 {												\
736 	struct mmc_card *card = mmc_dev_to_card(dev);						\
737 												\
738 	if (num > card->num_info)								\
739 		return -ENODATA;								\
740 	if (!card->info[num - 1][0])								\
741 		return 0;									\
742 	return sysfs_emit(buf, "%s\n", card->info[num - 1]);					\
743 }												\
744 static DEVICE_ATTR_RO(info##num)
745 
746 sdio_info_attr(1);
747 sdio_info_attr(2);
748 sdio_info_attr(3);
749 sdio_info_attr(4);
750 
751 static struct attribute *sd_std_attrs[] = {
752 	&dev_attr_vendor.attr,
753 	&dev_attr_device.attr,
754 	&dev_attr_revision.attr,
755 	&dev_attr_info1.attr,
756 	&dev_attr_info2.attr,
757 	&dev_attr_info3.attr,
758 	&dev_attr_info4.attr,
759 	&dev_attr_cid.attr,
760 	&dev_attr_csd.attr,
761 	&dev_attr_scr.attr,
762 	&dev_attr_ssr.attr,
763 	&dev_attr_date.attr,
764 	&dev_attr_erase_size.attr,
765 	&dev_attr_preferred_erase_size.attr,
766 	&dev_attr_fwrev.attr,
767 	&dev_attr_hwrev.attr,
768 	&dev_attr_manfid.attr,
769 	&dev_attr_name.attr,
770 	&dev_attr_oemid.attr,
771 	&dev_attr_serial.attr,
772 	&dev_attr_ocr.attr,
773 	&dev_attr_rca.attr,
774 	&dev_attr_dsr.attr,
775 	NULL,
776 };
777 
sd_std_is_visible(struct kobject * kobj,struct attribute * attr,int index)778 static umode_t sd_std_is_visible(struct kobject *kobj, struct attribute *attr,
779 				 int index)
780 {
781 	struct device *dev = kobj_to_dev(kobj);
782 	struct mmc_card *card = mmc_dev_to_card(dev);
783 
784 	/* CIS vendor and device ids, revision and info string are available only for Combo cards */
785 	if ((attr == &dev_attr_vendor.attr ||
786 	     attr == &dev_attr_device.attr ||
787 	     attr == &dev_attr_revision.attr ||
788 	     attr == &dev_attr_info1.attr ||
789 	     attr == &dev_attr_info2.attr ||
790 	     attr == &dev_attr_info3.attr ||
791 	     attr == &dev_attr_info4.attr
792 	    ) &&!mmc_card_sd_combo(card))
793 		return 0;
794 
795 	return attr->mode;
796 }
797 
798 static const struct attribute_group sd_std_group = {
799 	.attrs = sd_std_attrs,
800 	.is_visible = sd_std_is_visible,
801 };
802 __ATTRIBUTE_GROUPS(sd_std);
803 
804 const struct device_type sd_type = {
805 	.groups = sd_std_groups,
806 };
807 
808 /*
809  * Fetch CID from card.
810  */
mmc_sd_get_cid(struct mmc_host * host,u32 ocr,u32 * cid,u32 * rocr)811 int mmc_sd_get_cid(struct mmc_host *host, u32 ocr, u32 *cid, u32 *rocr)
812 {
813 	int err;
814 	u32 max_current;
815 	int retries = 10;
816 	u32 pocr = ocr;
817 
818 try_again:
819 	if (!retries) {
820 		ocr &= ~SD_OCR_S18R;
821 		pr_warn("%s: Skipping voltage switch\n", mmc_hostname(host));
822 	}
823 
824 	/*
825 	 * Since we're changing the OCR value, we seem to
826 	 * need to tell some cards to go back to the idle
827 	 * state.  We wait 1ms to give cards time to
828 	 * respond.
829 	 */
830 	mmc_go_idle(host);
831 
832 	/*
833 	 * If SD_SEND_IF_COND indicates an SD 2.0
834 	 * compliant card and we should set bit 30
835 	 * of the ocr to indicate that we can handle
836 	 * block-addressed SDHC cards.
837 	 */
838 	err = mmc_send_if_cond(host, ocr);
839 	if (!err) {
840 		ocr |= SD_OCR_CCS;
841 		/* Set HO2T as well - SDUC card won't respond otherwise */
842 		ocr |= SD_OCR_2T;
843 	}
844 
845 	/*
846 	 * If the host supports one of UHS-I modes, request the card
847 	 * to switch to 1.8V signaling level. If the card has failed
848 	 * repeatedly to switch however, skip this.
849 	 */
850 	if (retries && mmc_host_uhs(host))
851 		ocr |= SD_OCR_S18R;
852 
853 	/*
854 	 * If the host can supply more than 150mA at current voltage,
855 	 * XPC should be set to 1.
856 	 */
857 	max_current = sd_get_host_max_current(host);
858 	if (max_current > 150)
859 		ocr |= SD_OCR_XPC;
860 
861 	err = mmc_send_app_op_cond(host, ocr, rocr);
862 	if (err)
863 		return err;
864 
865 	/*
866 	 * In case the S18A bit is set in the response, let's start the signal
867 	 * voltage switch procedure. SPI mode doesn't support CMD11.
868 	 * Note that, according to the spec, the S18A bit is not valid unless
869 	 * the CCS bit is set as well. We deliberately deviate from the spec in
870 	 * regards to this, which allows UHS-I to be supported for SDSC cards.
871 	 */
872 	if (!mmc_host_is_spi(host) && (ocr & SD_OCR_S18R) &&
873 	    rocr && (*rocr & SD_ROCR_S18A)) {
874 		err = mmc_set_uhs_voltage(host, pocr);
875 		if (err == -EAGAIN) {
876 			retries--;
877 			goto try_again;
878 		} else if (err) {
879 			retries = 0;
880 			goto try_again;
881 		}
882 	}
883 
884 	err = mmc_send_cid(host, cid);
885 	return err;
886 }
887 
mmc_sd_get_csd(struct mmc_card * card,bool is_sduc)888 int mmc_sd_get_csd(struct mmc_card *card, bool is_sduc)
889 {
890 	int err;
891 
892 	/*
893 	 * Fetch CSD from card.
894 	 */
895 	err = mmc_send_csd(card, card->raw_csd);
896 	if (err)
897 		return err;
898 
899 	err = mmc_decode_csd(card, is_sduc);
900 	if (err)
901 		return err;
902 
903 	return 0;
904 }
905 
mmc_sd_get_ro(struct mmc_host * host)906 int mmc_sd_get_ro(struct mmc_host *host)
907 {
908 	int ro;
909 
910 	/*
911 	 * Some systems don't feature a write-protect pin and don't need one.
912 	 * E.g. because they only have micro-SD card slot. For those systems
913 	 * assume that the SD card is always read-write.
914 	 */
915 	if (host->caps2 & MMC_CAP2_NO_WRITE_PROTECT)
916 		return 0;
917 
918 	if (!host->ops->get_ro)
919 		return -1;
920 
921 	ro = host->ops->get_ro(host);
922 
923 	return ro;
924 }
925 
mmc_sd_setup_card(struct mmc_host * host,struct mmc_card * card,bool reinit)926 int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card,
927 	bool reinit)
928 {
929 	int err;
930 
931 	if (!reinit) {
932 		/*
933 		 * Fetch SCR from card.
934 		 */
935 		err = mmc_app_send_scr(card);
936 		if (err)
937 			return err;
938 
939 		err = mmc_decode_scr(card);
940 		if (err)
941 			return err;
942 
943 		/*
944 		 * Fetch and process SD Status register.
945 		 */
946 		err = mmc_read_ssr(card);
947 		if (err)
948 			return err;
949 
950 		/* Erase init depends on CSD and SSR */
951 		mmc_init_erase(card);
952 	}
953 
954 	/*
955 	 * Fetch switch information from card. Note, sd3_bus_mode can change if
956 	 * voltage switch outcome changes, so do this always.
957 	 */
958 	err = mmc_read_switch(card);
959 	if (err)
960 		return err;
961 
962 	/*
963 	 * For SPI, enable CRC as appropriate.
964 	 * This CRC enable is located AFTER the reading of the
965 	 * card registers because some SDHC cards are not able
966 	 * to provide valid CRCs for non-512-byte blocks.
967 	 */
968 	if (mmc_host_is_spi(host)) {
969 		err = mmc_spi_set_crc(host, use_spi_crc);
970 		if (err)
971 			return err;
972 	}
973 
974 	/*
975 	 * Check if read-only switch is active.
976 	 */
977 	if (!reinit) {
978 		int ro = mmc_sd_get_ro(host);
979 
980 		if (ro < 0) {
981 			pr_warn("%s: host does not support reading read-only switch, assuming write-enable\n",
982 				mmc_hostname(host));
983 		} else if (ro > 0) {
984 			mmc_card_set_readonly(card);
985 		}
986 	}
987 
988 	return 0;
989 }
990 
mmc_sd_get_max_clock(struct mmc_card * card)991 unsigned mmc_sd_get_max_clock(struct mmc_card *card)
992 {
993 	unsigned max_dtr = (unsigned int)-1;
994 
995 	if (mmc_card_hs(card)) {
996 		if (max_dtr > card->sw_caps.hs_max_dtr)
997 			max_dtr = card->sw_caps.hs_max_dtr;
998 	} else if (max_dtr > card->csd.max_dtr) {
999 		max_dtr = card->csd.max_dtr;
1000 	}
1001 
1002 	return max_dtr;
1003 }
1004 
mmc_sd_card_using_v18(struct mmc_card * card)1005 static bool mmc_sd_card_using_v18(struct mmc_card *card)
1006 {
1007 	/*
1008 	 * According to the SD spec., the Bus Speed Mode (function group 1) bits
1009 	 * 2 to 4 are zero if the card is initialized at 3.3V signal level. Thus
1010 	 * they can be used to determine if the card has already switched to
1011 	 * 1.8V signaling.
1012 	 */
1013 	return card->sw_caps.sd3_bus_mode &
1014 	       (SD_MODE_UHS_SDR50 | SD_MODE_UHS_SDR104 | SD_MODE_UHS_DDR50);
1015 }
1016 
sd_write_ext_reg(struct mmc_card * card,u8 fno,u8 page,u16 offset,u8 reg_data)1017 static int sd_write_ext_reg(struct mmc_card *card, u8 fno, u8 page, u16 offset,
1018 			    u8 reg_data)
1019 {
1020 	struct mmc_host *host = card->host;
1021 	struct mmc_request mrq = {};
1022 	struct mmc_command cmd = {};
1023 	struct mmc_data data = {};
1024 	struct scatterlist sg;
1025 	u8 *reg_buf;
1026 
1027 	reg_buf = kzalloc(512, GFP_KERNEL);
1028 	if (!reg_buf)
1029 		return -ENOMEM;
1030 
1031 	mrq.cmd = &cmd;
1032 	mrq.data = &data;
1033 
1034 	/*
1035 	 * Arguments of CMD49:
1036 	 * [31:31] MIO (0 = memory).
1037 	 * [30:27] FNO (function number).
1038 	 * [26:26] MW - mask write mode (0 = disable).
1039 	 * [25:18] page number.
1040 	 * [17:9] offset address.
1041 	 * [8:0] length (0 = 1 byte).
1042 	 */
1043 	cmd.arg = fno << 27 | page << 18 | offset << 9;
1044 
1045 	/* The first byte in the buffer is the data to be written. */
1046 	reg_buf[0] = reg_data;
1047 
1048 	data.flags = MMC_DATA_WRITE;
1049 	data.blksz = 512;
1050 	data.blocks = 1;
1051 	data.sg = &sg;
1052 	data.sg_len = 1;
1053 	sg_init_one(&sg, reg_buf, 512);
1054 
1055 	cmd.opcode = SD_WRITE_EXTR_SINGLE;
1056 	cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
1057 
1058 	mmc_set_data_timeout(&data, card);
1059 	mmc_wait_for_req(host, &mrq);
1060 
1061 	kfree(reg_buf);
1062 
1063 	/*
1064 	 * Note that, the SD card is allowed to signal busy on DAT0 up to 1s
1065 	 * after the CMD49. Although, let's leave this to be managed by the
1066 	 * caller.
1067 	 */
1068 
1069 	if (cmd.error)
1070 		return cmd.error;
1071 	if (data.error)
1072 		return data.error;
1073 
1074 	return 0;
1075 }
1076 
sd_read_ext_reg(struct mmc_card * card,u8 fno,u8 page,u16 offset,u16 len,u8 * reg_buf)1077 static int sd_read_ext_reg(struct mmc_card *card, u8 fno, u8 page,
1078 			   u16 offset, u16 len, u8 *reg_buf)
1079 {
1080 	u32 cmd_args;
1081 
1082 	/*
1083 	 * Command arguments of CMD48:
1084 	 * [31:31] MIO (0 = memory).
1085 	 * [30:27] FNO (function number).
1086 	 * [26:26] reserved (0).
1087 	 * [25:18] page number.
1088 	 * [17:9] offset address.
1089 	 * [8:0] length (0 = 1 byte, 1ff = 512 bytes).
1090 	 */
1091 	cmd_args = fno << 27 | page << 18 | offset << 9 | (len -1);
1092 
1093 	return mmc_send_adtc_data(card, card->host, SD_READ_EXTR_SINGLE,
1094 				  cmd_args, reg_buf, 512);
1095 }
1096 
sd_parse_ext_reg_power(struct mmc_card * card,u8 fno,u8 page,u16 offset)1097 static int sd_parse_ext_reg_power(struct mmc_card *card, u8 fno, u8 page,
1098 				  u16 offset)
1099 {
1100 	int err;
1101 	u8 *reg_buf;
1102 
1103 	reg_buf = kzalloc(512, GFP_KERNEL);
1104 	if (!reg_buf)
1105 		return -ENOMEM;
1106 
1107 	/* Read the extension register for power management function. */
1108 	err = sd_read_ext_reg(card, fno, page, offset, 512, reg_buf);
1109 	if (err) {
1110 		pr_warn("%s: error %d reading PM func of ext reg\n",
1111 			mmc_hostname(card->host), err);
1112 		goto out;
1113 	}
1114 
1115 	/* PM revision consists of 4 bits. */
1116 	card->ext_power.rev = reg_buf[0] & 0xf;
1117 
1118 	/* Power Off Notification support at bit 4. */
1119 	if ((reg_buf[1] & BIT(4)) && !mmc_card_broken_sd_poweroff_notify(card))
1120 		card->ext_power.feature_support |= SD_EXT_POWER_OFF_NOTIFY;
1121 
1122 	/* Power Sustenance support at bit 5. */
1123 	if (reg_buf[1] & BIT(5))
1124 		card->ext_power.feature_support |= SD_EXT_POWER_SUSTENANCE;
1125 
1126 	/* Power Down Mode support at bit 6. */
1127 	if (reg_buf[1] & BIT(6))
1128 		card->ext_power.feature_support |= SD_EXT_POWER_DOWN_MODE;
1129 
1130 	card->ext_power.fno = fno;
1131 	card->ext_power.page = page;
1132 	card->ext_power.offset = offset;
1133 
1134 out:
1135 	kfree(reg_buf);
1136 	return err;
1137 }
1138 
sd_parse_ext_reg_perf(struct mmc_card * card,u8 fno,u8 page,u16 offset)1139 static int sd_parse_ext_reg_perf(struct mmc_card *card, u8 fno, u8 page,
1140 				 u16 offset)
1141 {
1142 	int err;
1143 	u8 *reg_buf;
1144 
1145 	reg_buf = kzalloc(512, GFP_KERNEL);
1146 	if (!reg_buf)
1147 		return -ENOMEM;
1148 
1149 	err = sd_read_ext_reg(card, fno, page, offset, 512, reg_buf);
1150 	if (err) {
1151 		pr_warn("%s: error %d reading PERF func of ext reg\n",
1152 			mmc_hostname(card->host), err);
1153 		goto out;
1154 	}
1155 
1156 	/* PERF revision. */
1157 	card->ext_perf.rev = reg_buf[0];
1158 
1159 	/* FX_EVENT support at bit 0. */
1160 	if (reg_buf[1] & BIT(0))
1161 		card->ext_perf.feature_support |= SD_EXT_PERF_FX_EVENT;
1162 
1163 	/* Card initiated self-maintenance support at bit 0. */
1164 	if (reg_buf[2] & BIT(0))
1165 		card->ext_perf.feature_support |= SD_EXT_PERF_CARD_MAINT;
1166 
1167 	/* Host initiated self-maintenance support at bit 1. */
1168 	if (reg_buf[2] & BIT(1))
1169 		card->ext_perf.feature_support |= SD_EXT_PERF_HOST_MAINT;
1170 
1171 	/* Cache support at bit 0. */
1172 	if ((reg_buf[4] & BIT(0)) && !mmc_card_broken_sd_cache(card))
1173 		card->ext_perf.feature_support |= SD_EXT_PERF_CACHE;
1174 
1175 	/* Command queue support indicated via queue depth bits (0 to 4). */
1176 	if (reg_buf[6] & 0x1f)
1177 		card->ext_perf.feature_support |= SD_EXT_PERF_CMD_QUEUE;
1178 
1179 	card->ext_perf.fno = fno;
1180 	card->ext_perf.page = page;
1181 	card->ext_perf.offset = offset;
1182 
1183 out:
1184 	kfree(reg_buf);
1185 	return err;
1186 }
1187 
sd_parse_ext_reg(struct mmc_card * card,u8 * gen_info_buf,u16 * next_ext_addr)1188 static int sd_parse_ext_reg(struct mmc_card *card, u8 *gen_info_buf,
1189 			    u16 *next_ext_addr)
1190 {
1191 	u8 num_regs, fno, page;
1192 	u16 sfc, offset, ext = *next_ext_addr;
1193 	u32 reg_addr;
1194 
1195 	/*
1196 	 * Parse only one register set per extension, as that is sufficient to
1197 	 * support the standard functions. This means another 48 bytes in the
1198 	 * buffer must be available.
1199 	 */
1200 	if (ext + 48 > 512)
1201 		return -EFAULT;
1202 
1203 	/* Standard Function Code */
1204 	memcpy(&sfc, &gen_info_buf[ext], 2);
1205 
1206 	/* Address to the next extension. */
1207 	memcpy(next_ext_addr, &gen_info_buf[ext + 40], 2);
1208 
1209 	/* Number of registers for this extension. */
1210 	num_regs = gen_info_buf[ext + 42];
1211 
1212 	/* We support only one register per extension. */
1213 	if (num_regs != 1)
1214 		return 0;
1215 
1216 	/* Extension register address. */
1217 	memcpy(&reg_addr, &gen_info_buf[ext + 44], 4);
1218 
1219 	/* 9 bits (0 to 8) contains the offset address. */
1220 	offset = reg_addr & 0x1ff;
1221 
1222 	/* 8 bits (9 to 16) contains the page number. */
1223 	page = reg_addr >> 9 & 0xff ;
1224 
1225 	/* 4 bits (18 to 21) contains the function number. */
1226 	fno = reg_addr >> 18 & 0xf;
1227 
1228 	/* Standard Function Code for power management. */
1229 	if (sfc == 0x1)
1230 		return sd_parse_ext_reg_power(card, fno, page, offset);
1231 
1232 	/* Standard Function Code for performance enhancement. */
1233 	if (sfc == 0x2)
1234 		return sd_parse_ext_reg_perf(card, fno, page, offset);
1235 
1236 	return 0;
1237 }
1238 
sd_read_ext_regs(struct mmc_card * card)1239 static int sd_read_ext_regs(struct mmc_card *card)
1240 {
1241 	int err, i;
1242 	u8 num_ext, *gen_info_buf;
1243 	u16 rev, len, next_ext_addr;
1244 
1245 	if (mmc_host_is_spi(card->host))
1246 		return 0;
1247 
1248 	if (!(card->scr.cmds & SD_SCR_CMD48_SUPPORT))
1249 		return 0;
1250 
1251 	gen_info_buf = kzalloc(512, GFP_KERNEL);
1252 	if (!gen_info_buf)
1253 		return -ENOMEM;
1254 
1255 	/*
1256 	 * Read 512 bytes of general info, which is found at function number 0,
1257 	 * at page 0 and with no offset.
1258 	 */
1259 	err = sd_read_ext_reg(card, 0, 0, 0, 512, gen_info_buf);
1260 	if (err) {
1261 		pr_err("%s: error %d reading general info of SD ext reg\n",
1262 			mmc_hostname(card->host), err);
1263 		goto out;
1264 	}
1265 
1266 	/* General info structure revision. */
1267 	memcpy(&rev, &gen_info_buf[0], 2);
1268 
1269 	/* Length of general info in bytes. */
1270 	memcpy(&len, &gen_info_buf[2], 2);
1271 
1272 	/* Number of extensions to be find. */
1273 	num_ext = gen_info_buf[4];
1274 
1275 	/*
1276 	 * We only support revision 0 and limit it to 512 bytes for simplicity.
1277 	 * No matter what, let's return zero to allow us to continue using the
1278 	 * card, even if we can't support the features from the SD function
1279 	 * extensions registers.
1280 	 */
1281 	if (rev != 0 || len > 512) {
1282 		pr_warn("%s: non-supported SD ext reg layout\n",
1283 			mmc_hostname(card->host));
1284 		goto out;
1285 	}
1286 
1287 	/*
1288 	 * Parse the extension registers. The first extension should start
1289 	 * immediately after the general info header (16 bytes).
1290 	 */
1291 	next_ext_addr = 16;
1292 	for (i = 0; i < num_ext; i++) {
1293 		err = sd_parse_ext_reg(card, gen_info_buf, &next_ext_addr);
1294 		if (err) {
1295 			pr_err("%s: error %d parsing SD ext reg\n",
1296 				mmc_hostname(card->host), err);
1297 			goto out;
1298 		}
1299 	}
1300 
1301 out:
1302 	kfree(gen_info_buf);
1303 	return err;
1304 }
1305 
sd_cache_enabled(struct mmc_host * host)1306 static bool sd_cache_enabled(struct mmc_host *host)
1307 {
1308 	return host->card->ext_perf.feature_enabled & SD_EXT_PERF_CACHE;
1309 }
1310 
sd_flush_cache(struct mmc_host * host)1311 static int sd_flush_cache(struct mmc_host *host)
1312 {
1313 	struct mmc_card *card = host->card;
1314 	u8 *reg_buf, fno, page;
1315 	u16 offset;
1316 	int err;
1317 
1318 	if (!sd_cache_enabled(host))
1319 		return 0;
1320 
1321 	reg_buf = kzalloc(512, GFP_KERNEL);
1322 	if (!reg_buf)
1323 		return -ENOMEM;
1324 
1325 	/*
1326 	 * Set Flush Cache at bit 0 in the performance enhancement register at
1327 	 * 261 bytes offset.
1328 	 */
1329 	fno = card->ext_perf.fno;
1330 	page = card->ext_perf.page;
1331 	offset = card->ext_perf.offset + 261;
1332 
1333 	err = sd_write_ext_reg(card, fno, page, offset, BIT(0));
1334 	if (err) {
1335 		pr_warn("%s: error %d writing Cache Flush bit\n",
1336 			mmc_hostname(host), err);
1337 		goto out;
1338 	}
1339 
1340 	err = mmc_poll_for_busy(card, SD_WRITE_EXTR_SINGLE_TIMEOUT_MS, false,
1341 				MMC_BUSY_EXTR_SINGLE);
1342 	if (err)
1343 		goto out;
1344 
1345 	/*
1346 	 * Read the Flush Cache bit. The card shall reset it, to confirm that
1347 	 * it's has completed the flushing of the cache.
1348 	 */
1349 	err = sd_read_ext_reg(card, fno, page, offset, 1, reg_buf);
1350 	if (err) {
1351 		pr_warn("%s: error %d reading Cache Flush bit\n",
1352 			mmc_hostname(host), err);
1353 		goto out;
1354 	}
1355 
1356 	if (reg_buf[0] & BIT(0))
1357 		err = -ETIMEDOUT;
1358 out:
1359 	kfree(reg_buf);
1360 	return err;
1361 }
1362 
sd_enable_cache(struct mmc_card * card)1363 static int sd_enable_cache(struct mmc_card *card)
1364 {
1365 	u8 *reg_buf;
1366 	int err;
1367 
1368 	card->ext_perf.feature_enabled &= ~SD_EXT_PERF_CACHE;
1369 
1370 	reg_buf = kzalloc(512, GFP_KERNEL);
1371 	if (!reg_buf)
1372 		return -ENOMEM;
1373 
1374 	/*
1375 	 * Set Cache Enable at bit 0 in the performance enhancement register at
1376 	 * 260 bytes offset.
1377 	 */
1378 	err = sd_write_ext_reg(card, card->ext_perf.fno, card->ext_perf.page,
1379 			       card->ext_perf.offset + 260, BIT(0));
1380 	if (err) {
1381 		pr_warn("%s: error %d writing Cache Enable bit\n",
1382 			mmc_hostname(card->host), err);
1383 		goto out;
1384 	}
1385 
1386 	err = mmc_poll_for_busy(card, SD_WRITE_EXTR_SINGLE_TIMEOUT_MS, false,
1387 				MMC_BUSY_EXTR_SINGLE);
1388 	if (!err)
1389 		card->ext_perf.feature_enabled |= SD_EXT_PERF_CACHE;
1390 
1391 out:
1392 	kfree(reg_buf);
1393 	return err;
1394 }
1395 
1396 /*
1397  * Handle the detection and initialisation of a card.
1398  *
1399  * In the case of a resume, "oldcard" will contain the card
1400  * we're trying to reinitialise.
1401  */
mmc_sd_init_card(struct mmc_host * host,u32 ocr,struct mmc_card * oldcard)1402 static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
1403 	struct mmc_card *oldcard)
1404 {
1405 	struct mmc_card *card;
1406 	int err;
1407 	u32 cid[4];
1408 	u32 rocr = 0;
1409 	bool v18_fixup_failed = false;
1410 
1411 	WARN_ON(!host->claimed);
1412 retry:
1413 	err = mmc_sd_get_cid(host, ocr, cid, &rocr);
1414 	if (err)
1415 		return err;
1416 
1417 	if (oldcard) {
1418 		if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0) {
1419 			pr_debug("%s: Perhaps the card was replaced\n",
1420 				mmc_hostname(host));
1421 			return -ENOENT;
1422 		}
1423 
1424 		card = oldcard;
1425 	} else {
1426 		/*
1427 		 * Allocate card structure.
1428 		 */
1429 		card = mmc_alloc_card(host, &sd_type);
1430 		if (IS_ERR(card))
1431 			return PTR_ERR(card);
1432 
1433 		card->ocr = ocr;
1434 		card->type = MMC_TYPE_SD;
1435 		memcpy(card->raw_cid, cid, sizeof(card->raw_cid));
1436 	}
1437 
1438 	/*
1439 	 * Call the optional HC's init_card function to handle quirks.
1440 	 */
1441 	if (host->ops->init_card)
1442 		host->ops->init_card(host, card);
1443 
1444 	/*
1445 	 * For native busses:  get card RCA and quit open drain mode.
1446 	 */
1447 	if (!mmc_host_is_spi(host)) {
1448 		err = mmc_send_relative_addr(host, &card->rca);
1449 		if (err)
1450 			goto free_card;
1451 	}
1452 
1453 	if (!oldcard) {
1454 		u32 sduc_arg = SD_OCR_CCS | SD_OCR_2T;
1455 		bool is_sduc = (rocr & sduc_arg) == sduc_arg;
1456 
1457 		err = mmc_sd_get_csd(card, is_sduc);
1458 		if (err)
1459 			goto free_card;
1460 
1461 		mmc_decode_cid(card);
1462 	}
1463 
1464 	/*
1465 	 * handling only for cards supporting DSR and hosts requesting
1466 	 * DSR configuration
1467 	 */
1468 	if (card->csd.dsr_imp && host->dsr_req)
1469 		mmc_set_dsr(host);
1470 
1471 	/*
1472 	 * Select card, as all following commands rely on that.
1473 	 */
1474 	if (!mmc_host_is_spi(host)) {
1475 		err = mmc_select_card(card);
1476 		if (err)
1477 			goto free_card;
1478 	}
1479 
1480 	/* Apply quirks prior to card setup */
1481 	mmc_fixup_device(card, mmc_sd_fixups);
1482 
1483 	err = mmc_sd_setup_card(host, card, oldcard != NULL);
1484 	if (err)
1485 		goto free_card;
1486 
1487 	/*
1488 	 * If the card has not been power cycled, it may still be using 1.8V
1489 	 * signaling. Detect that situation and try to initialize a UHS-I (1.8V)
1490 	 * transfer mode.
1491 	 */
1492 	if (!v18_fixup_failed && !mmc_host_is_spi(host) && mmc_host_uhs(host) &&
1493 	    mmc_sd_card_using_v18(card) &&
1494 	    host->ios.signal_voltage != MMC_SIGNAL_VOLTAGE_180) {
1495 		if (mmc_host_set_uhs_voltage(host) ||
1496 		    mmc_sd_init_uhs_card(card)) {
1497 			v18_fixup_failed = true;
1498 			mmc_power_cycle(host, ocr);
1499 			if (!oldcard)
1500 				mmc_remove_card(card);
1501 			goto retry;
1502 		}
1503 		goto cont;
1504 	}
1505 
1506 	/* Initialization sequence for UHS-I cards */
1507 	if (rocr & SD_ROCR_S18A && mmc_host_uhs(host)) {
1508 		err = mmc_sd_init_uhs_card(card);
1509 		if (err)
1510 			goto free_card;
1511 	} else {
1512 		/*
1513 		 * Attempt to change to high-speed (if supported)
1514 		 */
1515 		err = mmc_sd_switch_hs(card);
1516 		if (err > 0)
1517 			mmc_set_timing(card->host, MMC_TIMING_SD_HS);
1518 		else if (err)
1519 			goto free_card;
1520 
1521 		/*
1522 		 * Set bus speed.
1523 		 */
1524 		mmc_set_clock(host, mmc_sd_get_max_clock(card));
1525 
1526 		if (host->ios.timing == MMC_TIMING_SD_HS &&
1527 			host->ops->prepare_sd_hs_tuning) {
1528 			err = host->ops->prepare_sd_hs_tuning(host, card);
1529 			if (err)
1530 				goto free_card;
1531 		}
1532 
1533 		/*
1534 		 * Switch to wider bus (if supported).
1535 		 */
1536 		if ((host->caps & MMC_CAP_4_BIT_DATA) &&
1537 			(card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) {
1538 			err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4);
1539 			if (err)
1540 				goto free_card;
1541 
1542 			mmc_set_bus_width(host, MMC_BUS_WIDTH_4);
1543 		}
1544 
1545 		if (host->ios.timing == MMC_TIMING_SD_HS &&
1546 			host->ops->execute_sd_hs_tuning) {
1547 			err = host->ops->execute_sd_hs_tuning(host, card);
1548 			if (err)
1549 				goto free_card;
1550 		}
1551 	}
1552 cont:
1553 	if (!oldcard) {
1554 		/* Read/parse the extension registers. */
1555 		err = sd_read_ext_regs(card);
1556 		if (err)
1557 			goto free_card;
1558 	}
1559 
1560 	/* Enable internal SD cache if supported. */
1561 	if (card->ext_perf.feature_support & SD_EXT_PERF_CACHE) {
1562 		err = sd_enable_cache(card);
1563 		if (err)
1564 			goto free_card;
1565 	}
1566 
1567 	if (!mmc_card_ult_capacity(card) && host->cqe_ops && !host->cqe_enabled) {
1568 		err = host->cqe_ops->cqe_enable(host, card);
1569 		if (!err) {
1570 			host->cqe_enabled = true;
1571 			host->hsq_enabled = true;
1572 			pr_info("%s: Host Software Queue enabled\n",
1573 				mmc_hostname(host));
1574 		}
1575 	}
1576 
1577 	if (host->caps2 & MMC_CAP2_AVOID_3_3V &&
1578 	    host->ios.signal_voltage == MMC_SIGNAL_VOLTAGE_330) {
1579 		pr_err("%s: Host failed to negotiate down from 3.3V\n",
1580 			mmc_hostname(host));
1581 		err = -EINVAL;
1582 		goto free_card;
1583 	}
1584 
1585 	host->card = card;
1586 	return 0;
1587 
1588 free_card:
1589 	if (!oldcard)
1590 		mmc_remove_card(card);
1591 
1592 	return err;
1593 }
1594 
1595 /*
1596  * Host is being removed. Free up the current card.
1597  */
mmc_sd_remove(struct mmc_host * host)1598 static void mmc_sd_remove(struct mmc_host *host)
1599 {
1600 	mmc_remove_card(host->card);
1601 	host->card = NULL;
1602 }
1603 
1604 /*
1605  * Card detection - card is alive.
1606  */
mmc_sd_alive(struct mmc_host * host)1607 static int mmc_sd_alive(struct mmc_host *host)
1608 {
1609 	return mmc_send_status(host->card, NULL);
1610 }
1611 
1612 /*
1613  * Card detection callback from host.
1614  */
mmc_sd_detect(struct mmc_host * host)1615 static void mmc_sd_detect(struct mmc_host *host)
1616 {
1617 	int err;
1618 
1619 	mmc_get_card(host->card, NULL);
1620 
1621 	/*
1622 	 * Just check if our card has been removed.
1623 	 */
1624 	err = _mmc_detect_card_removed(host);
1625 
1626 	mmc_put_card(host->card, NULL);
1627 
1628 	if (err) {
1629 		mmc_sd_remove(host);
1630 
1631 		mmc_claim_host(host);
1632 		mmc_detach_bus(host);
1633 		mmc_power_off(host);
1634 		mmc_release_host(host);
1635 	}
1636 }
1637 
sd_can_poweroff_notify(struct mmc_card * card)1638 static int sd_can_poweroff_notify(struct mmc_card *card)
1639 {
1640 	return card->ext_power.feature_support & SD_EXT_POWER_OFF_NOTIFY;
1641 }
1642 
sd_busy_poweroff_notify_cb(void * cb_data,bool * busy)1643 static int sd_busy_poweroff_notify_cb(void *cb_data, bool *busy)
1644 {
1645 	struct sd_busy_data *data = cb_data;
1646 	struct mmc_card *card = data->card;
1647 	int err;
1648 
1649 	/*
1650 	 * Read the status register for the power management function. It's at
1651 	 * one byte offset and is one byte long. The Power Off Notification
1652 	 * Ready is bit 0.
1653 	 */
1654 	err = sd_read_ext_reg(card, card->ext_power.fno, card->ext_power.page,
1655 			      card->ext_power.offset + 1, 1, data->reg_buf);
1656 	if (err) {
1657 		pr_warn("%s: error %d reading status reg of PM func\n",
1658 			mmc_hostname(card->host), err);
1659 		return err;
1660 	}
1661 
1662 	*busy = !(data->reg_buf[0] & BIT(0));
1663 	return 0;
1664 }
1665 
sd_poweroff_notify(struct mmc_card * card)1666 static int sd_poweroff_notify(struct mmc_card *card)
1667 {
1668 	struct sd_busy_data cb_data;
1669 	u8 *reg_buf;
1670 	int err;
1671 
1672 	reg_buf = kzalloc(512, GFP_KERNEL);
1673 	if (!reg_buf)
1674 		return -ENOMEM;
1675 
1676 	/*
1677 	 * Set the Power Off Notification bit in the power management settings
1678 	 * register at 2 bytes offset.
1679 	 */
1680 	err = sd_write_ext_reg(card, card->ext_power.fno, card->ext_power.page,
1681 			       card->ext_power.offset + 2, BIT(0));
1682 	if (err) {
1683 		pr_warn("%s: error %d writing Power Off Notify bit\n",
1684 			mmc_hostname(card->host), err);
1685 		goto out;
1686 	}
1687 
1688 	/* Find out when the command is completed. */
1689 	err = mmc_poll_for_busy(card, SD_WRITE_EXTR_SINGLE_TIMEOUT_MS, false,
1690 				MMC_BUSY_EXTR_SINGLE);
1691 	if (err)
1692 		goto out;
1693 
1694 	cb_data.card = card;
1695 	cb_data.reg_buf = reg_buf;
1696 	err = __mmc_poll_for_busy(card->host, 0, SD_POWEROFF_NOTIFY_TIMEOUT_MS,
1697 				  &sd_busy_poweroff_notify_cb, &cb_data);
1698 
1699 out:
1700 	kfree(reg_buf);
1701 	return err;
1702 }
1703 
_mmc_sd_suspend(struct mmc_host * host)1704 static int _mmc_sd_suspend(struct mmc_host *host)
1705 {
1706 	struct mmc_card *card = host->card;
1707 	int err = 0;
1708 
1709 	mmc_claim_host(host);
1710 
1711 	if (mmc_card_suspended(card))
1712 		goto out;
1713 
1714 	if (sd_can_poweroff_notify(card))
1715 		err = sd_poweroff_notify(card);
1716 	else if (!mmc_host_is_spi(host))
1717 		err = mmc_deselect_cards(host);
1718 
1719 	if (!err) {
1720 		mmc_power_off(host);
1721 		mmc_card_set_suspended(card);
1722 	}
1723 
1724 out:
1725 	mmc_release_host(host);
1726 	return err;
1727 }
1728 
1729 /*
1730  * Callback for suspend
1731  */
mmc_sd_suspend(struct mmc_host * host)1732 static int mmc_sd_suspend(struct mmc_host *host)
1733 {
1734 	int err;
1735 
1736 	err = _mmc_sd_suspend(host);
1737 	if (!err) {
1738 		pm_runtime_disable(&host->card->dev);
1739 		pm_runtime_set_suspended(&host->card->dev);
1740 	}
1741 
1742 	return err;
1743 }
1744 
1745 /*
1746  * This function tries to determine if the same card is still present
1747  * and, if so, restore all state to it.
1748  */
_mmc_sd_resume(struct mmc_host * host)1749 static int _mmc_sd_resume(struct mmc_host *host)
1750 {
1751 	int err = 0;
1752 
1753 	mmc_claim_host(host);
1754 
1755 	if (!mmc_card_suspended(host->card))
1756 		goto out;
1757 
1758 	mmc_power_up(host, host->card->ocr);
1759 	err = mmc_sd_init_card(host, host->card->ocr, host->card);
1760 	mmc_card_clr_suspended(host->card);
1761 
1762 out:
1763 	mmc_release_host(host);
1764 	return err;
1765 }
1766 
1767 /*
1768  * Callback for resume
1769  */
mmc_sd_resume(struct mmc_host * host)1770 static int mmc_sd_resume(struct mmc_host *host)
1771 {
1772 	pm_runtime_enable(&host->card->dev);
1773 	return 0;
1774 }
1775 
1776 /*
1777  * Callback for runtime_suspend.
1778  */
mmc_sd_runtime_suspend(struct mmc_host * host)1779 static int mmc_sd_runtime_suspend(struct mmc_host *host)
1780 {
1781 	int err;
1782 
1783 	if (!(host->caps & MMC_CAP_AGGRESSIVE_PM))
1784 		return 0;
1785 
1786 	err = _mmc_sd_suspend(host);
1787 	if (err)
1788 		pr_err("%s: error %d doing aggressive suspend\n",
1789 			mmc_hostname(host), err);
1790 
1791 	return err;
1792 }
1793 
1794 /*
1795  * Callback for runtime_resume.
1796  */
mmc_sd_runtime_resume(struct mmc_host * host)1797 static int mmc_sd_runtime_resume(struct mmc_host *host)
1798 {
1799 	int err;
1800 
1801 	err = _mmc_sd_resume(host);
1802 	if (err && err != -ENOMEDIUM)
1803 		pr_err("%s: error %d doing runtime resume\n",
1804 			mmc_hostname(host), err);
1805 
1806 	return 0;
1807 }
1808 
mmc_sd_hw_reset(struct mmc_host * host)1809 static int mmc_sd_hw_reset(struct mmc_host *host)
1810 {
1811 	mmc_power_cycle(host, host->card->ocr);
1812 	return mmc_sd_init_card(host, host->card->ocr, host->card);
1813 }
1814 
1815 static const struct mmc_bus_ops mmc_sd_ops = {
1816 	.remove = mmc_sd_remove,
1817 	.detect = mmc_sd_detect,
1818 	.runtime_suspend = mmc_sd_runtime_suspend,
1819 	.runtime_resume = mmc_sd_runtime_resume,
1820 	.suspend = mmc_sd_suspend,
1821 	.resume = mmc_sd_resume,
1822 	.alive = mmc_sd_alive,
1823 	.shutdown = mmc_sd_suspend,
1824 	.hw_reset = mmc_sd_hw_reset,
1825 	.cache_enabled = sd_cache_enabled,
1826 	.flush_cache = sd_flush_cache,
1827 };
1828 
1829 /*
1830  * Starting point for SD card init.
1831  */
mmc_attach_sd(struct mmc_host * host)1832 int mmc_attach_sd(struct mmc_host *host)
1833 {
1834 	int err;
1835 	u32 ocr, rocr;
1836 
1837 	WARN_ON(!host->claimed);
1838 
1839 	err = mmc_send_app_op_cond(host, 0, &ocr);
1840 	if (err)
1841 		return err;
1842 
1843 	mmc_attach_bus(host, &mmc_sd_ops);
1844 	if (host->ocr_avail_sd)
1845 		host->ocr_avail = host->ocr_avail_sd;
1846 
1847 	/*
1848 	 * We need to get OCR a different way for SPI.
1849 	 */
1850 	if (mmc_host_is_spi(host)) {
1851 		mmc_go_idle(host);
1852 
1853 		err = mmc_spi_read_ocr(host, 0, &ocr);
1854 		if (err)
1855 			goto err;
1856 	}
1857 
1858 	/*
1859 	 * Some SD cards claims an out of spec VDD voltage range. Let's treat
1860 	 * these bits as being in-valid and especially also bit7.
1861 	 */
1862 	ocr &= ~0x7FFF;
1863 
1864 	rocr = mmc_select_voltage(host, ocr);
1865 
1866 	/*
1867 	 * Can we support the voltage(s) of the card(s)?
1868 	 */
1869 	if (!rocr) {
1870 		err = -EINVAL;
1871 		goto err;
1872 	}
1873 
1874 	/*
1875 	 * Detect and init the card.
1876 	 */
1877 	err = mmc_sd_init_card(host, rocr, NULL);
1878 	if (err)
1879 		goto err;
1880 
1881 	mmc_release_host(host);
1882 	err = mmc_add_card(host->card);
1883 	if (err)
1884 		goto remove_card;
1885 
1886 	mmc_claim_host(host);
1887 	return 0;
1888 
1889 remove_card:
1890 	mmc_remove_card(host->card);
1891 	host->card = NULL;
1892 	mmc_claim_host(host);
1893 err:
1894 	mmc_detach_bus(host);
1895 
1896 	pr_err("%s: error %d whilst initialising SD card\n",
1897 		mmc_hostname(host), err);
1898 
1899 	return err;
1900 }
1901