xref: /openbmc/linux/drivers/mmc/core/core.c (revision d35ac6ac)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/drivers/mmc/core/core.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) 2005-2008 Pierre Ossman, All Rights Reserved.
8  *  MMCv4 support Copyright (C) 2006 Philip Langdale, All Rights Reserved.
9  */
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/interrupt.h>
13 #include <linux/completion.h>
14 #include <linux/device.h>
15 #include <linux/delay.h>
16 #include <linux/pagemap.h>
17 #include <linux/err.h>
18 #include <linux/leds.h>
19 #include <linux/scatterlist.h>
20 #include <linux/log2.h>
21 #include <linux/pm_runtime.h>
22 #include <linux/pm_wakeup.h>
23 #include <linux/suspend.h>
24 #include <linux/fault-inject.h>
25 #include <linux/random.h>
26 #include <linux/slab.h>
27 #include <linux/of.h>
28 
29 #include <linux/mmc/card.h>
30 #include <linux/mmc/host.h>
31 #include <linux/mmc/mmc.h>
32 #include <linux/mmc/sd.h>
33 #include <linux/mmc/slot-gpio.h>
34 
35 #define CREATE_TRACE_POINTS
36 #include <trace/events/mmc.h>
37 
38 #include "core.h"
39 #include "card.h"
40 #include "crypto.h"
41 #include "bus.h"
42 #include "host.h"
43 #include "sdio_bus.h"
44 #include "pwrseq.h"
45 
46 #include "mmc_ops.h"
47 #include "sd_ops.h"
48 #include "sdio_ops.h"
49 
50 /* The max erase timeout, used when host->max_busy_timeout isn't specified */
51 #define MMC_ERASE_TIMEOUT_MS	(60 * 1000) /* 60 s */
52 #define SD_DISCARD_TIMEOUT_MS	(250)
53 
54 static const unsigned freqs[] = { 400000, 300000, 200000, 100000 };
55 
56 /*
57  * Enabling software CRCs on the data blocks can be a significant (30%)
58  * performance cost, and for other reasons may not always be desired.
59  * So we allow it to be disabled.
60  */
61 bool use_spi_crc = 1;
62 module_param(use_spi_crc, bool, 0);
63 
64 static int mmc_schedule_delayed_work(struct delayed_work *work,
65 				     unsigned long delay)
66 {
67 	/*
68 	 * We use the system_freezable_wq, because of two reasons.
69 	 * First, it allows several works (not the same work item) to be
70 	 * executed simultaneously. Second, the queue becomes frozen when
71 	 * userspace becomes frozen during system PM.
72 	 */
73 	return queue_delayed_work(system_freezable_wq, work, delay);
74 }
75 
76 #ifdef CONFIG_FAIL_MMC_REQUEST
77 
78 /*
79  * Internal function. Inject random data errors.
80  * If mmc_data is NULL no errors are injected.
81  */
82 static void mmc_should_fail_request(struct mmc_host *host,
83 				    struct mmc_request *mrq)
84 {
85 	struct mmc_command *cmd = mrq->cmd;
86 	struct mmc_data *data = mrq->data;
87 	static const int data_errors[] = {
88 		-ETIMEDOUT,
89 		-EILSEQ,
90 		-EIO,
91 	};
92 
93 	if (!data)
94 		return;
95 
96 	if ((cmd && cmd->error) || data->error ||
97 	    !should_fail(&host->fail_mmc_request, data->blksz * data->blocks))
98 		return;
99 
100 	data->error = data_errors[get_random_u32_below(ARRAY_SIZE(data_errors))];
101 	data->bytes_xfered = get_random_u32_below(data->bytes_xfered >> 9) << 9;
102 }
103 
104 #else /* CONFIG_FAIL_MMC_REQUEST */
105 
106 static inline void mmc_should_fail_request(struct mmc_host *host,
107 					   struct mmc_request *mrq)
108 {
109 }
110 
111 #endif /* CONFIG_FAIL_MMC_REQUEST */
112 
113 static inline void mmc_complete_cmd(struct mmc_request *mrq)
114 {
115 	if (mrq->cap_cmd_during_tfr && !completion_done(&mrq->cmd_completion))
116 		complete_all(&mrq->cmd_completion);
117 }
118 
119 void mmc_command_done(struct mmc_host *host, struct mmc_request *mrq)
120 {
121 	if (!mrq->cap_cmd_during_tfr)
122 		return;
123 
124 	mmc_complete_cmd(mrq);
125 
126 	pr_debug("%s: cmd done, tfr ongoing (CMD%u)\n",
127 		 mmc_hostname(host), mrq->cmd->opcode);
128 }
129 EXPORT_SYMBOL(mmc_command_done);
130 
131 /**
132  *	mmc_request_done - finish processing an MMC request
133  *	@host: MMC host which completed request
134  *	@mrq: MMC request which request
135  *
136  *	MMC drivers should call this function when they have completed
137  *	their processing of a request.
138  */
139 void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
140 {
141 	struct mmc_command *cmd = mrq->cmd;
142 	int err = cmd->error;
143 
144 	/* Flag re-tuning needed on CRC errors */
145 	if (!mmc_op_tuning(cmd->opcode) &&
146 	    !host->retune_crc_disable &&
147 	    (err == -EILSEQ || (mrq->sbc && mrq->sbc->error == -EILSEQ) ||
148 	    (mrq->data && mrq->data->error == -EILSEQ) ||
149 	    (mrq->stop && mrq->stop->error == -EILSEQ)))
150 		mmc_retune_needed(host);
151 
152 	if (err && cmd->retries && mmc_host_is_spi(host)) {
153 		if (cmd->resp[0] & R1_SPI_ILLEGAL_COMMAND)
154 			cmd->retries = 0;
155 	}
156 
157 	if (host->ongoing_mrq == mrq)
158 		host->ongoing_mrq = NULL;
159 
160 	mmc_complete_cmd(mrq);
161 
162 	trace_mmc_request_done(host, mrq);
163 
164 	/*
165 	 * We list various conditions for the command to be considered
166 	 * properly done:
167 	 *
168 	 * - There was no error, OK fine then
169 	 * - We are not doing some kind of retry
170 	 * - The card was removed (...so just complete everything no matter
171 	 *   if there are errors or retries)
172 	 */
173 	if (!err || !cmd->retries || mmc_card_removed(host->card)) {
174 		mmc_should_fail_request(host, mrq);
175 
176 		if (!host->ongoing_mrq)
177 			led_trigger_event(host->led, LED_OFF);
178 
179 		if (mrq->sbc) {
180 			pr_debug("%s: req done <CMD%u>: %d: %08x %08x %08x %08x\n",
181 				mmc_hostname(host), mrq->sbc->opcode,
182 				mrq->sbc->error,
183 				mrq->sbc->resp[0], mrq->sbc->resp[1],
184 				mrq->sbc->resp[2], mrq->sbc->resp[3]);
185 		}
186 
187 		pr_debug("%s: req done (CMD%u): %d: %08x %08x %08x %08x\n",
188 			mmc_hostname(host), cmd->opcode, err,
189 			cmd->resp[0], cmd->resp[1],
190 			cmd->resp[2], cmd->resp[3]);
191 
192 		if (mrq->data) {
193 			pr_debug("%s:     %d bytes transferred: %d\n",
194 				mmc_hostname(host),
195 				mrq->data->bytes_xfered, mrq->data->error);
196 		}
197 
198 		if (mrq->stop) {
199 			pr_debug("%s:     (CMD%u): %d: %08x %08x %08x %08x\n",
200 				mmc_hostname(host), mrq->stop->opcode,
201 				mrq->stop->error,
202 				mrq->stop->resp[0], mrq->stop->resp[1],
203 				mrq->stop->resp[2], mrq->stop->resp[3]);
204 		}
205 	}
206 	/*
207 	 * Request starter must handle retries - see
208 	 * mmc_wait_for_req_done().
209 	 */
210 	if (mrq->done)
211 		mrq->done(mrq);
212 }
213 
214 EXPORT_SYMBOL(mmc_request_done);
215 
216 static void __mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
217 {
218 	int err;
219 
220 	/* Assumes host controller has been runtime resumed by mmc_claim_host */
221 	err = mmc_retune(host);
222 	if (err) {
223 		mrq->cmd->error = err;
224 		mmc_request_done(host, mrq);
225 		return;
226 	}
227 
228 	/*
229 	 * For sdio rw commands we must wait for card busy otherwise some
230 	 * sdio devices won't work properly.
231 	 * And bypass I/O abort, reset and bus suspend operations.
232 	 */
233 	if (sdio_is_io_busy(mrq->cmd->opcode, mrq->cmd->arg) &&
234 	    host->ops->card_busy) {
235 		int tries = 500; /* Wait aprox 500ms at maximum */
236 
237 		while (host->ops->card_busy(host) && --tries)
238 			mmc_delay(1);
239 
240 		if (tries == 0) {
241 			mrq->cmd->error = -EBUSY;
242 			mmc_request_done(host, mrq);
243 			return;
244 		}
245 	}
246 
247 	if (mrq->cap_cmd_during_tfr) {
248 		host->ongoing_mrq = mrq;
249 		/*
250 		 * Retry path could come through here without having waiting on
251 		 * cmd_completion, so ensure it is reinitialised.
252 		 */
253 		reinit_completion(&mrq->cmd_completion);
254 	}
255 
256 	trace_mmc_request_start(host, mrq);
257 
258 	if (host->cqe_on)
259 		host->cqe_ops->cqe_off(host);
260 
261 	host->ops->request(host, mrq);
262 }
263 
264 static void mmc_mrq_pr_debug(struct mmc_host *host, struct mmc_request *mrq,
265 			     bool cqe)
266 {
267 	if (mrq->sbc) {
268 		pr_debug("<%s: starting CMD%u arg %08x flags %08x>\n",
269 			 mmc_hostname(host), mrq->sbc->opcode,
270 			 mrq->sbc->arg, mrq->sbc->flags);
271 	}
272 
273 	if (mrq->cmd) {
274 		pr_debug("%s: starting %sCMD%u arg %08x flags %08x\n",
275 			 mmc_hostname(host), cqe ? "CQE direct " : "",
276 			 mrq->cmd->opcode, mrq->cmd->arg, mrq->cmd->flags);
277 	} else if (cqe) {
278 		pr_debug("%s: starting CQE transfer for tag %d blkaddr %u\n",
279 			 mmc_hostname(host), mrq->tag, mrq->data->blk_addr);
280 	}
281 
282 	if (mrq->data) {
283 		pr_debug("%s:     blksz %d blocks %d flags %08x "
284 			"tsac %d ms nsac %d\n",
285 			mmc_hostname(host), mrq->data->blksz,
286 			mrq->data->blocks, mrq->data->flags,
287 			mrq->data->timeout_ns / 1000000,
288 			mrq->data->timeout_clks);
289 	}
290 
291 	if (mrq->stop) {
292 		pr_debug("%s:     CMD%u arg %08x flags %08x\n",
293 			 mmc_hostname(host), mrq->stop->opcode,
294 			 mrq->stop->arg, mrq->stop->flags);
295 	}
296 }
297 
298 static int mmc_mrq_prep(struct mmc_host *host, struct mmc_request *mrq)
299 {
300 	unsigned int i, sz = 0;
301 	struct scatterlist *sg;
302 
303 	if (mrq->cmd) {
304 		mrq->cmd->error = 0;
305 		mrq->cmd->mrq = mrq;
306 		mrq->cmd->data = mrq->data;
307 	}
308 	if (mrq->sbc) {
309 		mrq->sbc->error = 0;
310 		mrq->sbc->mrq = mrq;
311 	}
312 	if (mrq->data) {
313 		if (mrq->data->blksz > host->max_blk_size ||
314 		    mrq->data->blocks > host->max_blk_count ||
315 		    mrq->data->blocks * mrq->data->blksz > host->max_req_size)
316 			return -EINVAL;
317 
318 		for_each_sg(mrq->data->sg, sg, mrq->data->sg_len, i)
319 			sz += sg->length;
320 		if (sz != mrq->data->blocks * mrq->data->blksz)
321 			return -EINVAL;
322 
323 		mrq->data->error = 0;
324 		mrq->data->mrq = mrq;
325 		if (mrq->stop) {
326 			mrq->data->stop = mrq->stop;
327 			mrq->stop->error = 0;
328 			mrq->stop->mrq = mrq;
329 		}
330 	}
331 
332 	return 0;
333 }
334 
335 int mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
336 {
337 	int err;
338 
339 	init_completion(&mrq->cmd_completion);
340 
341 	mmc_retune_hold(host);
342 
343 	if (mmc_card_removed(host->card))
344 		return -ENOMEDIUM;
345 
346 	mmc_mrq_pr_debug(host, mrq, false);
347 
348 	WARN_ON(!host->claimed);
349 
350 	err = mmc_mrq_prep(host, mrq);
351 	if (err)
352 		return err;
353 
354 	led_trigger_event(host->led, LED_FULL);
355 	__mmc_start_request(host, mrq);
356 
357 	return 0;
358 }
359 EXPORT_SYMBOL(mmc_start_request);
360 
361 static void mmc_wait_done(struct mmc_request *mrq)
362 {
363 	complete(&mrq->completion);
364 }
365 
366 static inline void mmc_wait_ongoing_tfr_cmd(struct mmc_host *host)
367 {
368 	struct mmc_request *ongoing_mrq = READ_ONCE(host->ongoing_mrq);
369 
370 	/*
371 	 * If there is an ongoing transfer, wait for the command line to become
372 	 * available.
373 	 */
374 	if (ongoing_mrq && !completion_done(&ongoing_mrq->cmd_completion))
375 		wait_for_completion(&ongoing_mrq->cmd_completion);
376 }
377 
378 static int __mmc_start_req(struct mmc_host *host, struct mmc_request *mrq)
379 {
380 	int err;
381 
382 	mmc_wait_ongoing_tfr_cmd(host);
383 
384 	init_completion(&mrq->completion);
385 	mrq->done = mmc_wait_done;
386 
387 	err = mmc_start_request(host, mrq);
388 	if (err) {
389 		mrq->cmd->error = err;
390 		mmc_complete_cmd(mrq);
391 		complete(&mrq->completion);
392 	}
393 
394 	return err;
395 }
396 
397 void mmc_wait_for_req_done(struct mmc_host *host, struct mmc_request *mrq)
398 {
399 	struct mmc_command *cmd;
400 
401 	while (1) {
402 		wait_for_completion(&mrq->completion);
403 
404 		cmd = mrq->cmd;
405 
406 		if (!cmd->error || !cmd->retries ||
407 		    mmc_card_removed(host->card))
408 			break;
409 
410 		mmc_retune_recheck(host);
411 
412 		pr_debug("%s: req failed (CMD%u): %d, retrying...\n",
413 			 mmc_hostname(host), cmd->opcode, cmd->error);
414 		cmd->retries--;
415 		cmd->error = 0;
416 		__mmc_start_request(host, mrq);
417 	}
418 
419 	mmc_retune_release(host);
420 }
421 EXPORT_SYMBOL(mmc_wait_for_req_done);
422 
423 /*
424  * mmc_cqe_start_req - Start a CQE request.
425  * @host: MMC host to start the request
426  * @mrq: request to start
427  *
428  * Start the request, re-tuning if needed and it is possible. Returns an error
429  * code if the request fails to start or -EBUSY if CQE is busy.
430  */
431 int mmc_cqe_start_req(struct mmc_host *host, struct mmc_request *mrq)
432 {
433 	int err;
434 
435 	/*
436 	 * CQE cannot process re-tuning commands. Caller must hold retuning
437 	 * while CQE is in use.  Re-tuning can happen here only when CQE has no
438 	 * active requests i.e. this is the first.  Note, re-tuning will call
439 	 * ->cqe_off().
440 	 */
441 	err = mmc_retune(host);
442 	if (err)
443 		goto out_err;
444 
445 	mrq->host = host;
446 
447 	mmc_mrq_pr_debug(host, mrq, true);
448 
449 	err = mmc_mrq_prep(host, mrq);
450 	if (err)
451 		goto out_err;
452 
453 	err = host->cqe_ops->cqe_request(host, mrq);
454 	if (err)
455 		goto out_err;
456 
457 	trace_mmc_request_start(host, mrq);
458 
459 	return 0;
460 
461 out_err:
462 	if (mrq->cmd) {
463 		pr_debug("%s: failed to start CQE direct CMD%u, error %d\n",
464 			 mmc_hostname(host), mrq->cmd->opcode, err);
465 	} else {
466 		pr_debug("%s: failed to start CQE transfer for tag %d, error %d\n",
467 			 mmc_hostname(host), mrq->tag, err);
468 	}
469 	return err;
470 }
471 EXPORT_SYMBOL(mmc_cqe_start_req);
472 
473 /**
474  *	mmc_cqe_request_done - CQE has finished processing an MMC request
475  *	@host: MMC host which completed request
476  *	@mrq: MMC request which completed
477  *
478  *	CQE drivers should call this function when they have completed
479  *	their processing of a request.
480  */
481 void mmc_cqe_request_done(struct mmc_host *host, struct mmc_request *mrq)
482 {
483 	mmc_should_fail_request(host, mrq);
484 
485 	/* Flag re-tuning needed on CRC errors */
486 	if ((mrq->cmd && mrq->cmd->error == -EILSEQ) ||
487 	    (mrq->data && mrq->data->error == -EILSEQ))
488 		mmc_retune_needed(host);
489 
490 	trace_mmc_request_done(host, mrq);
491 
492 	if (mrq->cmd) {
493 		pr_debug("%s: CQE req done (direct CMD%u): %d\n",
494 			 mmc_hostname(host), mrq->cmd->opcode, mrq->cmd->error);
495 	} else {
496 		pr_debug("%s: CQE transfer done tag %d\n",
497 			 mmc_hostname(host), mrq->tag);
498 	}
499 
500 	if (mrq->data) {
501 		pr_debug("%s:     %d bytes transferred: %d\n",
502 			 mmc_hostname(host),
503 			 mrq->data->bytes_xfered, mrq->data->error);
504 	}
505 
506 	mrq->done(mrq);
507 }
508 EXPORT_SYMBOL(mmc_cqe_request_done);
509 
510 /**
511  *	mmc_cqe_post_req - CQE post process of a completed MMC request
512  *	@host: MMC host
513  *	@mrq: MMC request to be processed
514  */
515 void mmc_cqe_post_req(struct mmc_host *host, struct mmc_request *mrq)
516 {
517 	if (host->cqe_ops->cqe_post_req)
518 		host->cqe_ops->cqe_post_req(host, mrq);
519 }
520 EXPORT_SYMBOL(mmc_cqe_post_req);
521 
522 /* Arbitrary 1 second timeout */
523 #define MMC_CQE_RECOVERY_TIMEOUT	1000
524 
525 /*
526  * mmc_cqe_recovery - Recover from CQE errors.
527  * @host: MMC host to recover
528  *
529  * Recovery consists of stopping CQE, stopping eMMC, discarding the queue
530  * in eMMC, and discarding the queue in CQE. CQE must call
531  * mmc_cqe_request_done() on all requests. An error is returned if the eMMC
532  * fails to discard its queue.
533  */
534 int mmc_cqe_recovery(struct mmc_host *host)
535 {
536 	struct mmc_command cmd;
537 	int err;
538 
539 	mmc_retune_hold_now(host);
540 
541 	/*
542 	 * Recovery is expected seldom, if at all, but it reduces performance,
543 	 * so make sure it is not completely silent.
544 	 */
545 	pr_warn("%s: running CQE recovery\n", mmc_hostname(host));
546 
547 	host->cqe_ops->cqe_recovery_start(host);
548 
549 	memset(&cmd, 0, sizeof(cmd));
550 	cmd.opcode       = MMC_STOP_TRANSMISSION;
551 	cmd.flags        = MMC_RSP_R1B | MMC_CMD_AC;
552 	cmd.flags       &= ~MMC_RSP_CRC; /* Ignore CRC */
553 	cmd.busy_timeout = MMC_CQE_RECOVERY_TIMEOUT;
554 	mmc_wait_for_cmd(host, &cmd, 0);
555 
556 	memset(&cmd, 0, sizeof(cmd));
557 	cmd.opcode       = MMC_CMDQ_TASK_MGMT;
558 	cmd.arg          = 1; /* Discard entire queue */
559 	cmd.flags        = MMC_RSP_R1B | MMC_CMD_AC;
560 	cmd.flags       &= ~MMC_RSP_CRC; /* Ignore CRC */
561 	cmd.busy_timeout = MMC_CQE_RECOVERY_TIMEOUT;
562 	err = mmc_wait_for_cmd(host, &cmd, 0);
563 
564 	host->cqe_ops->cqe_recovery_finish(host);
565 
566 	mmc_retune_release(host);
567 
568 	return err;
569 }
570 EXPORT_SYMBOL(mmc_cqe_recovery);
571 
572 /**
573  *	mmc_is_req_done - Determine if a 'cap_cmd_during_tfr' request is done
574  *	@host: MMC host
575  *	@mrq: MMC request
576  *
577  *	mmc_is_req_done() is used with requests that have
578  *	mrq->cap_cmd_during_tfr = true. mmc_is_req_done() must be called after
579  *	starting a request and before waiting for it to complete. That is,
580  *	either in between calls to mmc_start_req(), or after mmc_wait_for_req()
581  *	and before mmc_wait_for_req_done(). If it is called at other times the
582  *	result is not meaningful.
583  */
584 bool mmc_is_req_done(struct mmc_host *host, struct mmc_request *mrq)
585 {
586 	return completion_done(&mrq->completion);
587 }
588 EXPORT_SYMBOL(mmc_is_req_done);
589 
590 /**
591  *	mmc_wait_for_req - start a request and wait for completion
592  *	@host: MMC host to start command
593  *	@mrq: MMC request to start
594  *
595  *	Start a new MMC custom command request for a host, and wait
596  *	for the command to complete. In the case of 'cap_cmd_during_tfr'
597  *	requests, the transfer is ongoing and the caller can issue further
598  *	commands that do not use the data lines, and then wait by calling
599  *	mmc_wait_for_req_done().
600  *	Does not attempt to parse the response.
601  */
602 void mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq)
603 {
604 	__mmc_start_req(host, mrq);
605 
606 	if (!mrq->cap_cmd_during_tfr)
607 		mmc_wait_for_req_done(host, mrq);
608 }
609 EXPORT_SYMBOL(mmc_wait_for_req);
610 
611 /**
612  *	mmc_wait_for_cmd - start a command and wait for completion
613  *	@host: MMC host to start command
614  *	@cmd: MMC command to start
615  *	@retries: maximum number of retries
616  *
617  *	Start a new MMC command for a host, and wait for the command
618  *	to complete.  Return any error that occurred while the command
619  *	was executing.  Do not attempt to parse the response.
620  */
621 int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries)
622 {
623 	struct mmc_request mrq = {};
624 
625 	WARN_ON(!host->claimed);
626 
627 	memset(cmd->resp, 0, sizeof(cmd->resp));
628 	cmd->retries = retries;
629 
630 	mrq.cmd = cmd;
631 	cmd->data = NULL;
632 
633 	mmc_wait_for_req(host, &mrq);
634 
635 	return cmd->error;
636 }
637 
638 EXPORT_SYMBOL(mmc_wait_for_cmd);
639 
640 /**
641  *	mmc_set_data_timeout - set the timeout for a data command
642  *	@data: data phase for command
643  *	@card: the MMC card associated with the data transfer
644  *
645  *	Computes the data timeout parameters according to the
646  *	correct algorithm given the card type.
647  */
648 void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card)
649 {
650 	unsigned int mult;
651 
652 	/*
653 	 * SDIO cards only define an upper 1 s limit on access.
654 	 */
655 	if (mmc_card_sdio(card)) {
656 		data->timeout_ns = 1000000000;
657 		data->timeout_clks = 0;
658 		return;
659 	}
660 
661 	/*
662 	 * SD cards use a 100 multiplier rather than 10
663 	 */
664 	mult = mmc_card_sd(card) ? 100 : 10;
665 
666 	/*
667 	 * Scale up the multiplier (and therefore the timeout) by
668 	 * the r2w factor for writes.
669 	 */
670 	if (data->flags & MMC_DATA_WRITE)
671 		mult <<= card->csd.r2w_factor;
672 
673 	data->timeout_ns = card->csd.taac_ns * mult;
674 	data->timeout_clks = card->csd.taac_clks * mult;
675 
676 	/*
677 	 * SD cards also have an upper limit on the timeout.
678 	 */
679 	if (mmc_card_sd(card)) {
680 		unsigned int timeout_us, limit_us;
681 
682 		timeout_us = data->timeout_ns / 1000;
683 		if (card->host->ios.clock)
684 			timeout_us += data->timeout_clks * 1000 /
685 				(card->host->ios.clock / 1000);
686 
687 		if (data->flags & MMC_DATA_WRITE)
688 			/*
689 			 * The MMC spec "It is strongly recommended
690 			 * for hosts to implement more than 500ms
691 			 * timeout value even if the card indicates
692 			 * the 250ms maximum busy length."  Even the
693 			 * previous value of 300ms is known to be
694 			 * insufficient for some cards.
695 			 */
696 			limit_us = 3000000;
697 		else
698 			limit_us = 100000;
699 
700 		/*
701 		 * SDHC cards always use these fixed values.
702 		 */
703 		if (timeout_us > limit_us) {
704 			data->timeout_ns = limit_us * 1000;
705 			data->timeout_clks = 0;
706 		}
707 
708 		/* assign limit value if invalid */
709 		if (timeout_us == 0)
710 			data->timeout_ns = limit_us * 1000;
711 	}
712 
713 	/*
714 	 * Some cards require longer data read timeout than indicated in CSD.
715 	 * Address this by setting the read timeout to a "reasonably high"
716 	 * value. For the cards tested, 600ms has proven enough. If necessary,
717 	 * this value can be increased if other problematic cards require this.
718 	 */
719 	if (mmc_card_long_read_time(card) && data->flags & MMC_DATA_READ) {
720 		data->timeout_ns = 600000000;
721 		data->timeout_clks = 0;
722 	}
723 
724 	/*
725 	 * Some cards need very high timeouts if driven in SPI mode.
726 	 * The worst observed timeout was 900ms after writing a
727 	 * continuous stream of data until the internal logic
728 	 * overflowed.
729 	 */
730 	if (mmc_host_is_spi(card->host)) {
731 		if (data->flags & MMC_DATA_WRITE) {
732 			if (data->timeout_ns < 1000000000)
733 				data->timeout_ns = 1000000000;	/* 1s */
734 		} else {
735 			if (data->timeout_ns < 100000000)
736 				data->timeout_ns =  100000000;	/* 100ms */
737 		}
738 	}
739 }
740 EXPORT_SYMBOL(mmc_set_data_timeout);
741 
742 /*
743  * Allow claiming an already claimed host if the context is the same or there is
744  * no context but the task is the same.
745  */
746 static inline bool mmc_ctx_matches(struct mmc_host *host, struct mmc_ctx *ctx,
747 				   struct task_struct *task)
748 {
749 	return host->claimer == ctx ||
750 	       (!ctx && task && host->claimer->task == task);
751 }
752 
753 static inline void mmc_ctx_set_claimer(struct mmc_host *host,
754 				       struct mmc_ctx *ctx,
755 				       struct task_struct *task)
756 {
757 	if (!host->claimer) {
758 		if (ctx)
759 			host->claimer = ctx;
760 		else
761 			host->claimer = &host->default_ctx;
762 	}
763 	if (task)
764 		host->claimer->task = task;
765 }
766 
767 /**
768  *	__mmc_claim_host - exclusively claim a host
769  *	@host: mmc host to claim
770  *	@ctx: context that claims the host or NULL in which case the default
771  *	context will be used
772  *	@abort: whether or not the operation should be aborted
773  *
774  *	Claim a host for a set of operations.  If @abort is non null and
775  *	dereference a non-zero value then this will return prematurely with
776  *	that non-zero value without acquiring the lock.  Returns zero
777  *	with the lock held otherwise.
778  */
779 int __mmc_claim_host(struct mmc_host *host, struct mmc_ctx *ctx,
780 		     atomic_t *abort)
781 {
782 	struct task_struct *task = ctx ? NULL : current;
783 	DECLARE_WAITQUEUE(wait, current);
784 	unsigned long flags;
785 	int stop;
786 	bool pm = false;
787 
788 	might_sleep();
789 
790 	add_wait_queue(&host->wq, &wait);
791 	spin_lock_irqsave(&host->lock, flags);
792 	while (1) {
793 		set_current_state(TASK_UNINTERRUPTIBLE);
794 		stop = abort ? atomic_read(abort) : 0;
795 		if (stop || !host->claimed || mmc_ctx_matches(host, ctx, task))
796 			break;
797 		spin_unlock_irqrestore(&host->lock, flags);
798 		schedule();
799 		spin_lock_irqsave(&host->lock, flags);
800 	}
801 	set_current_state(TASK_RUNNING);
802 	if (!stop) {
803 		host->claimed = 1;
804 		mmc_ctx_set_claimer(host, ctx, task);
805 		host->claim_cnt += 1;
806 		if (host->claim_cnt == 1)
807 			pm = true;
808 	} else
809 		wake_up(&host->wq);
810 	spin_unlock_irqrestore(&host->lock, flags);
811 	remove_wait_queue(&host->wq, &wait);
812 
813 	if (pm)
814 		pm_runtime_get_sync(mmc_dev(host));
815 
816 	return stop;
817 }
818 EXPORT_SYMBOL(__mmc_claim_host);
819 
820 /**
821  *	mmc_release_host - release a host
822  *	@host: mmc host to release
823  *
824  *	Release a MMC host, allowing others to claim the host
825  *	for their operations.
826  */
827 void mmc_release_host(struct mmc_host *host)
828 {
829 	unsigned long flags;
830 
831 	WARN_ON(!host->claimed);
832 
833 	spin_lock_irqsave(&host->lock, flags);
834 	if (--host->claim_cnt) {
835 		/* Release for nested claim */
836 		spin_unlock_irqrestore(&host->lock, flags);
837 	} else {
838 		host->claimed = 0;
839 		host->claimer->task = NULL;
840 		host->claimer = NULL;
841 		spin_unlock_irqrestore(&host->lock, flags);
842 		wake_up(&host->wq);
843 		pm_runtime_mark_last_busy(mmc_dev(host));
844 		if (host->caps & MMC_CAP_SYNC_RUNTIME_PM)
845 			pm_runtime_put_sync_suspend(mmc_dev(host));
846 		else
847 			pm_runtime_put_autosuspend(mmc_dev(host));
848 	}
849 }
850 EXPORT_SYMBOL(mmc_release_host);
851 
852 /*
853  * This is a helper function, which fetches a runtime pm reference for the
854  * card device and also claims the host.
855  */
856 void mmc_get_card(struct mmc_card *card, struct mmc_ctx *ctx)
857 {
858 	pm_runtime_get_sync(&card->dev);
859 	__mmc_claim_host(card->host, ctx, NULL);
860 }
861 EXPORT_SYMBOL(mmc_get_card);
862 
863 /*
864  * This is a helper function, which releases the host and drops the runtime
865  * pm reference for the card device.
866  */
867 void mmc_put_card(struct mmc_card *card, struct mmc_ctx *ctx)
868 {
869 	struct mmc_host *host = card->host;
870 
871 	WARN_ON(ctx && host->claimer != ctx);
872 
873 	mmc_release_host(host);
874 	pm_runtime_mark_last_busy(&card->dev);
875 	pm_runtime_put_autosuspend(&card->dev);
876 }
877 EXPORT_SYMBOL(mmc_put_card);
878 
879 /*
880  * Internal function that does the actual ios call to the host driver,
881  * optionally printing some debug output.
882  */
883 static inline void mmc_set_ios(struct mmc_host *host)
884 {
885 	struct mmc_ios *ios = &host->ios;
886 
887 	pr_debug("%s: clock %uHz busmode %u powermode %u cs %u Vdd %u "
888 		"width %u timing %u\n",
889 		 mmc_hostname(host), ios->clock, ios->bus_mode,
890 		 ios->power_mode, ios->chip_select, ios->vdd,
891 		 1 << ios->bus_width, ios->timing);
892 
893 	host->ops->set_ios(host, ios);
894 }
895 
896 /*
897  * Control chip select pin on a host.
898  */
899 void mmc_set_chip_select(struct mmc_host *host, int mode)
900 {
901 	host->ios.chip_select = mode;
902 	mmc_set_ios(host);
903 }
904 
905 /*
906  * Sets the host clock to the highest possible frequency that
907  * is below "hz".
908  */
909 void mmc_set_clock(struct mmc_host *host, unsigned int hz)
910 {
911 	WARN_ON(hz && hz < host->f_min);
912 
913 	if (hz > host->f_max)
914 		hz = host->f_max;
915 
916 	host->ios.clock = hz;
917 	mmc_set_ios(host);
918 }
919 
920 int mmc_execute_tuning(struct mmc_card *card)
921 {
922 	struct mmc_host *host = card->host;
923 	u32 opcode;
924 	int err;
925 
926 	if (!host->ops->execute_tuning)
927 		return 0;
928 
929 	if (host->cqe_on)
930 		host->cqe_ops->cqe_off(host);
931 
932 	if (mmc_card_mmc(card))
933 		opcode = MMC_SEND_TUNING_BLOCK_HS200;
934 	else
935 		opcode = MMC_SEND_TUNING_BLOCK;
936 
937 	err = host->ops->execute_tuning(host, opcode);
938 	if (!err) {
939 		mmc_retune_clear(host);
940 		mmc_retune_enable(host);
941 		return 0;
942 	}
943 
944 	/* Only print error when we don't check for card removal */
945 	if (!host->detect_change) {
946 		pr_err("%s: tuning execution failed: %d\n",
947 			mmc_hostname(host), err);
948 		mmc_debugfs_err_stats_inc(host, MMC_ERR_TUNING);
949 	}
950 
951 	return err;
952 }
953 
954 /*
955  * Change the bus mode (open drain/push-pull) of a host.
956  */
957 void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode)
958 {
959 	host->ios.bus_mode = mode;
960 	mmc_set_ios(host);
961 }
962 
963 /*
964  * Change data bus width of a host.
965  */
966 void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
967 {
968 	host->ios.bus_width = width;
969 	mmc_set_ios(host);
970 }
971 
972 /*
973  * Set initial state after a power cycle or a hw_reset.
974  */
975 void mmc_set_initial_state(struct mmc_host *host)
976 {
977 	if (host->cqe_on)
978 		host->cqe_ops->cqe_off(host);
979 
980 	mmc_retune_disable(host);
981 
982 	if (mmc_host_is_spi(host))
983 		host->ios.chip_select = MMC_CS_HIGH;
984 	else
985 		host->ios.chip_select = MMC_CS_DONTCARE;
986 	host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
987 	host->ios.bus_width = MMC_BUS_WIDTH_1;
988 	host->ios.timing = MMC_TIMING_LEGACY;
989 	host->ios.drv_type = 0;
990 	host->ios.enhanced_strobe = false;
991 
992 	/*
993 	 * Make sure we are in non-enhanced strobe mode before we
994 	 * actually enable it in ext_csd.
995 	 */
996 	if ((host->caps2 & MMC_CAP2_HS400_ES) &&
997 	     host->ops->hs400_enhanced_strobe)
998 		host->ops->hs400_enhanced_strobe(host, &host->ios);
999 
1000 	mmc_set_ios(host);
1001 
1002 	mmc_crypto_set_initial_state(host);
1003 }
1004 
1005 /**
1006  * mmc_vdd_to_ocrbitnum - Convert a voltage to the OCR bit number
1007  * @vdd:	voltage (mV)
1008  * @low_bits:	prefer low bits in boundary cases
1009  *
1010  * This function returns the OCR bit number according to the provided @vdd
1011  * value. If conversion is not possible a negative errno value returned.
1012  *
1013  * Depending on the @low_bits flag the function prefers low or high OCR bits
1014  * on boundary voltages. For example,
1015  * with @low_bits = true, 3300 mV translates to ilog2(MMC_VDD_32_33);
1016  * with @low_bits = false, 3300 mV translates to ilog2(MMC_VDD_33_34);
1017  *
1018  * Any value in the [1951:1999] range translates to the ilog2(MMC_VDD_20_21).
1019  */
1020 static int mmc_vdd_to_ocrbitnum(int vdd, bool low_bits)
1021 {
1022 	const int max_bit = ilog2(MMC_VDD_35_36);
1023 	int bit;
1024 
1025 	if (vdd < 1650 || vdd > 3600)
1026 		return -EINVAL;
1027 
1028 	if (vdd >= 1650 && vdd <= 1950)
1029 		return ilog2(MMC_VDD_165_195);
1030 
1031 	if (low_bits)
1032 		vdd -= 1;
1033 
1034 	/* Base 2000 mV, step 100 mV, bit's base 8. */
1035 	bit = (vdd - 2000) / 100 + 8;
1036 	if (bit > max_bit)
1037 		return max_bit;
1038 	return bit;
1039 }
1040 
1041 /**
1042  * mmc_vddrange_to_ocrmask - Convert a voltage range to the OCR mask
1043  * @vdd_min:	minimum voltage value (mV)
1044  * @vdd_max:	maximum voltage value (mV)
1045  *
1046  * This function returns the OCR mask bits according to the provided @vdd_min
1047  * and @vdd_max values. If conversion is not possible the function returns 0.
1048  *
1049  * Notes wrt boundary cases:
1050  * This function sets the OCR bits for all boundary voltages, for example
1051  * [3300:3400] range is translated to MMC_VDD_32_33 | MMC_VDD_33_34 |
1052  * MMC_VDD_34_35 mask.
1053  */
1054 u32 mmc_vddrange_to_ocrmask(int vdd_min, int vdd_max)
1055 {
1056 	u32 mask = 0;
1057 
1058 	if (vdd_max < vdd_min)
1059 		return 0;
1060 
1061 	/* Prefer high bits for the boundary vdd_max values. */
1062 	vdd_max = mmc_vdd_to_ocrbitnum(vdd_max, false);
1063 	if (vdd_max < 0)
1064 		return 0;
1065 
1066 	/* Prefer low bits for the boundary vdd_min values. */
1067 	vdd_min = mmc_vdd_to_ocrbitnum(vdd_min, true);
1068 	if (vdd_min < 0)
1069 		return 0;
1070 
1071 	/* Fill the mask, from max bit to min bit. */
1072 	while (vdd_max >= vdd_min)
1073 		mask |= 1 << vdd_max--;
1074 
1075 	return mask;
1076 }
1077 
1078 static int mmc_of_get_func_num(struct device_node *node)
1079 {
1080 	u32 reg;
1081 	int ret;
1082 
1083 	ret = of_property_read_u32(node, "reg", &reg);
1084 	if (ret < 0)
1085 		return ret;
1086 
1087 	return reg;
1088 }
1089 
1090 struct device_node *mmc_of_find_child_device(struct mmc_host *host,
1091 		unsigned func_num)
1092 {
1093 	struct device_node *node;
1094 
1095 	if (!host->parent || !host->parent->of_node)
1096 		return NULL;
1097 
1098 	for_each_child_of_node(host->parent->of_node, node) {
1099 		if (mmc_of_get_func_num(node) == func_num)
1100 			return node;
1101 	}
1102 
1103 	return NULL;
1104 }
1105 
1106 /*
1107  * Mask off any voltages we don't support and select
1108  * the lowest voltage
1109  */
1110 u32 mmc_select_voltage(struct mmc_host *host, u32 ocr)
1111 {
1112 	int bit;
1113 
1114 	/*
1115 	 * Sanity check the voltages that the card claims to
1116 	 * support.
1117 	 */
1118 	if (ocr & 0x7F) {
1119 		dev_warn(mmc_dev(host),
1120 		"card claims to support voltages below defined range\n");
1121 		ocr &= ~0x7F;
1122 	}
1123 
1124 	ocr &= host->ocr_avail;
1125 	if (!ocr) {
1126 		dev_warn(mmc_dev(host), "no support for card's volts\n");
1127 		return 0;
1128 	}
1129 
1130 	if (host->caps2 & MMC_CAP2_FULL_PWR_CYCLE) {
1131 		bit = ffs(ocr) - 1;
1132 		ocr &= 3 << bit;
1133 		mmc_power_cycle(host, ocr);
1134 	} else {
1135 		bit = fls(ocr) - 1;
1136 		/*
1137 		 * The bit variable represents the highest voltage bit set in
1138 		 * the OCR register.
1139 		 * To keep a range of 2 values (e.g. 3.2V/3.3V and 3.3V/3.4V),
1140 		 * we must shift the mask '3' with (bit - 1).
1141 		 */
1142 		ocr &= 3 << (bit - 1);
1143 		if (bit != host->ios.vdd)
1144 			dev_warn(mmc_dev(host), "exceeding card's volts\n");
1145 	}
1146 
1147 	return ocr;
1148 }
1149 
1150 int mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage)
1151 {
1152 	int err = 0;
1153 	int old_signal_voltage = host->ios.signal_voltage;
1154 
1155 	host->ios.signal_voltage = signal_voltage;
1156 	if (host->ops->start_signal_voltage_switch)
1157 		err = host->ops->start_signal_voltage_switch(host, &host->ios);
1158 
1159 	if (err)
1160 		host->ios.signal_voltage = old_signal_voltage;
1161 
1162 	return err;
1163 
1164 }
1165 
1166 void mmc_set_initial_signal_voltage(struct mmc_host *host)
1167 {
1168 	/* Try to set signal voltage to 3.3V but fall back to 1.8v or 1.2v */
1169 	if (!mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330))
1170 		dev_dbg(mmc_dev(host), "Initial signal voltage of 3.3v\n");
1171 	else if (!mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180))
1172 		dev_dbg(mmc_dev(host), "Initial signal voltage of 1.8v\n");
1173 	else if (!mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120))
1174 		dev_dbg(mmc_dev(host), "Initial signal voltage of 1.2v\n");
1175 }
1176 
1177 int mmc_host_set_uhs_voltage(struct mmc_host *host)
1178 {
1179 	u32 clock;
1180 
1181 	/*
1182 	 * During a signal voltage level switch, the clock must be gated
1183 	 * for 5 ms according to the SD spec
1184 	 */
1185 	clock = host->ios.clock;
1186 	host->ios.clock = 0;
1187 	mmc_set_ios(host);
1188 
1189 	if (mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180))
1190 		return -EAGAIN;
1191 
1192 	/* Keep clock gated for at least 10 ms, though spec only says 5 ms */
1193 	mmc_delay(10);
1194 	host->ios.clock = clock;
1195 	mmc_set_ios(host);
1196 
1197 	return 0;
1198 }
1199 
1200 int mmc_set_uhs_voltage(struct mmc_host *host, u32 ocr)
1201 {
1202 	struct mmc_command cmd = {};
1203 	int err = 0;
1204 
1205 	/*
1206 	 * If we cannot switch voltages, return failure so the caller
1207 	 * can continue without UHS mode
1208 	 */
1209 	if (!host->ops->start_signal_voltage_switch)
1210 		return -EPERM;
1211 	if (!host->ops->card_busy)
1212 		pr_warn("%s: cannot verify signal voltage switch\n",
1213 			mmc_hostname(host));
1214 
1215 	cmd.opcode = SD_SWITCH_VOLTAGE;
1216 	cmd.arg = 0;
1217 	cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
1218 
1219 	err = mmc_wait_for_cmd(host, &cmd, 0);
1220 	if (err)
1221 		goto power_cycle;
1222 
1223 	if (!mmc_host_is_spi(host) && (cmd.resp[0] & R1_ERROR))
1224 		return -EIO;
1225 
1226 	/*
1227 	 * The card should drive cmd and dat[0:3] low immediately
1228 	 * after the response of cmd11, but wait 1 ms to be sure
1229 	 */
1230 	mmc_delay(1);
1231 	if (host->ops->card_busy && !host->ops->card_busy(host)) {
1232 		err = -EAGAIN;
1233 		goto power_cycle;
1234 	}
1235 
1236 	if (mmc_host_set_uhs_voltage(host)) {
1237 		/*
1238 		 * Voltages may not have been switched, but we've already
1239 		 * sent CMD11, so a power cycle is required anyway
1240 		 */
1241 		err = -EAGAIN;
1242 		goto power_cycle;
1243 	}
1244 
1245 	/* Wait for at least 1 ms according to spec */
1246 	mmc_delay(1);
1247 
1248 	/*
1249 	 * Failure to switch is indicated by the card holding
1250 	 * dat[0:3] low
1251 	 */
1252 	if (host->ops->card_busy && host->ops->card_busy(host))
1253 		err = -EAGAIN;
1254 
1255 power_cycle:
1256 	if (err) {
1257 		pr_debug("%s: Signal voltage switch failed, "
1258 			"power cycling card\n", mmc_hostname(host));
1259 		mmc_power_cycle(host, ocr);
1260 	}
1261 
1262 	return err;
1263 }
1264 
1265 /*
1266  * Select timing parameters for host.
1267  */
1268 void mmc_set_timing(struct mmc_host *host, unsigned int timing)
1269 {
1270 	host->ios.timing = timing;
1271 	mmc_set_ios(host);
1272 }
1273 
1274 /*
1275  * Select appropriate driver type for host.
1276  */
1277 void mmc_set_driver_type(struct mmc_host *host, unsigned int drv_type)
1278 {
1279 	host->ios.drv_type = drv_type;
1280 	mmc_set_ios(host);
1281 }
1282 
1283 int mmc_select_drive_strength(struct mmc_card *card, unsigned int max_dtr,
1284 			      int card_drv_type, int *drv_type)
1285 {
1286 	struct mmc_host *host = card->host;
1287 	int host_drv_type = SD_DRIVER_TYPE_B;
1288 
1289 	*drv_type = 0;
1290 
1291 	if (!host->ops->select_drive_strength)
1292 		return 0;
1293 
1294 	/* Use SD definition of driver strength for hosts */
1295 	if (host->caps & MMC_CAP_DRIVER_TYPE_A)
1296 		host_drv_type |= SD_DRIVER_TYPE_A;
1297 
1298 	if (host->caps & MMC_CAP_DRIVER_TYPE_C)
1299 		host_drv_type |= SD_DRIVER_TYPE_C;
1300 
1301 	if (host->caps & MMC_CAP_DRIVER_TYPE_D)
1302 		host_drv_type |= SD_DRIVER_TYPE_D;
1303 
1304 	/*
1305 	 * The drive strength that the hardware can support
1306 	 * depends on the board design.  Pass the appropriate
1307 	 * information and let the hardware specific code
1308 	 * return what is possible given the options
1309 	 */
1310 	return host->ops->select_drive_strength(card, max_dtr,
1311 						host_drv_type,
1312 						card_drv_type,
1313 						drv_type);
1314 }
1315 
1316 /*
1317  * Apply power to the MMC stack.  This is a two-stage process.
1318  * First, we enable power to the card without the clock running.
1319  * We then wait a bit for the power to stabilise.  Finally,
1320  * enable the bus drivers and clock to the card.
1321  *
1322  * We must _NOT_ enable the clock prior to power stablising.
1323  *
1324  * If a host does all the power sequencing itself, ignore the
1325  * initial MMC_POWER_UP stage.
1326  */
1327 void mmc_power_up(struct mmc_host *host, u32 ocr)
1328 {
1329 	if (host->ios.power_mode == MMC_POWER_ON)
1330 		return;
1331 
1332 	mmc_pwrseq_pre_power_on(host);
1333 
1334 	host->ios.vdd = fls(ocr) - 1;
1335 	host->ios.power_mode = MMC_POWER_UP;
1336 	/* Set initial state and call mmc_set_ios */
1337 	mmc_set_initial_state(host);
1338 
1339 	mmc_set_initial_signal_voltage(host);
1340 
1341 	/*
1342 	 * This delay should be sufficient to allow the power supply
1343 	 * to reach the minimum voltage.
1344 	 */
1345 	mmc_delay(host->ios.power_delay_ms);
1346 
1347 	mmc_pwrseq_post_power_on(host);
1348 
1349 	host->ios.clock = host->f_init;
1350 
1351 	host->ios.power_mode = MMC_POWER_ON;
1352 	mmc_set_ios(host);
1353 
1354 	/*
1355 	 * This delay must be at least 74 clock sizes, or 1 ms, or the
1356 	 * time required to reach a stable voltage.
1357 	 */
1358 	mmc_delay(host->ios.power_delay_ms);
1359 }
1360 
1361 void mmc_power_off(struct mmc_host *host)
1362 {
1363 	if (host->ios.power_mode == MMC_POWER_OFF)
1364 		return;
1365 
1366 	mmc_pwrseq_power_off(host);
1367 
1368 	host->ios.clock = 0;
1369 	host->ios.vdd = 0;
1370 
1371 	host->ios.power_mode = MMC_POWER_OFF;
1372 	/* Set initial state and call mmc_set_ios */
1373 	mmc_set_initial_state(host);
1374 
1375 	/*
1376 	 * Some configurations, such as the 802.11 SDIO card in the OLPC
1377 	 * XO-1.5, require a short delay after poweroff before the card
1378 	 * can be successfully turned on again.
1379 	 */
1380 	mmc_delay(1);
1381 }
1382 
1383 void mmc_power_cycle(struct mmc_host *host, u32 ocr)
1384 {
1385 	mmc_power_off(host);
1386 	/* Wait at least 1 ms according to SD spec */
1387 	mmc_delay(1);
1388 	mmc_power_up(host, ocr);
1389 }
1390 
1391 /*
1392  * Assign a mmc bus handler to a host. Only one bus handler may control a
1393  * host at any given time.
1394  */
1395 void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops)
1396 {
1397 	host->bus_ops = ops;
1398 }
1399 
1400 /*
1401  * Remove the current bus handler from a host.
1402  */
1403 void mmc_detach_bus(struct mmc_host *host)
1404 {
1405 	host->bus_ops = NULL;
1406 }
1407 
1408 void _mmc_detect_change(struct mmc_host *host, unsigned long delay, bool cd_irq)
1409 {
1410 	/*
1411 	 * Prevent system sleep for 5s to allow user space to consume the
1412 	 * corresponding uevent. This is especially useful, when CD irq is used
1413 	 * as a system wakeup, but doesn't hurt in other cases.
1414 	 */
1415 	if (cd_irq && !(host->caps & MMC_CAP_NEEDS_POLL))
1416 		__pm_wakeup_event(host->ws, 5000);
1417 
1418 	host->detect_change = 1;
1419 	mmc_schedule_delayed_work(&host->detect, delay);
1420 }
1421 
1422 /**
1423  *	mmc_detect_change - process change of state on a MMC socket
1424  *	@host: host which changed state.
1425  *	@delay: optional delay to wait before detection (jiffies)
1426  *
1427  *	MMC drivers should call this when they detect a card has been
1428  *	inserted or removed. The MMC layer will confirm that any
1429  *	present card is still functional, and initialize any newly
1430  *	inserted.
1431  */
1432 void mmc_detect_change(struct mmc_host *host, unsigned long delay)
1433 {
1434 	_mmc_detect_change(host, delay, true);
1435 }
1436 EXPORT_SYMBOL(mmc_detect_change);
1437 
1438 void mmc_init_erase(struct mmc_card *card)
1439 {
1440 	unsigned int sz;
1441 
1442 	if (is_power_of_2(card->erase_size))
1443 		card->erase_shift = ffs(card->erase_size) - 1;
1444 	else
1445 		card->erase_shift = 0;
1446 
1447 	/*
1448 	 * It is possible to erase an arbitrarily large area of an SD or MMC
1449 	 * card.  That is not desirable because it can take a long time
1450 	 * (minutes) potentially delaying more important I/O, and also the
1451 	 * timeout calculations become increasingly hugely over-estimated.
1452 	 * Consequently, 'pref_erase' is defined as a guide to limit erases
1453 	 * to that size and alignment.
1454 	 *
1455 	 * For SD cards that define Allocation Unit size, limit erases to one
1456 	 * Allocation Unit at a time.
1457 	 * For MMC, have a stab at ai good value and for modern cards it will
1458 	 * end up being 4MiB. Note that if the value is too small, it can end
1459 	 * up taking longer to erase. Also note, erase_size is already set to
1460 	 * High Capacity Erase Size if available when this function is called.
1461 	 */
1462 	if (mmc_card_sd(card) && card->ssr.au) {
1463 		card->pref_erase = card->ssr.au;
1464 		card->erase_shift = ffs(card->ssr.au) - 1;
1465 	} else if (card->erase_size) {
1466 		sz = (card->csd.capacity << (card->csd.read_blkbits - 9)) >> 11;
1467 		if (sz < 128)
1468 			card->pref_erase = 512 * 1024 / 512;
1469 		else if (sz < 512)
1470 			card->pref_erase = 1024 * 1024 / 512;
1471 		else if (sz < 1024)
1472 			card->pref_erase = 2 * 1024 * 1024 / 512;
1473 		else
1474 			card->pref_erase = 4 * 1024 * 1024 / 512;
1475 		if (card->pref_erase < card->erase_size)
1476 			card->pref_erase = card->erase_size;
1477 		else {
1478 			sz = card->pref_erase % card->erase_size;
1479 			if (sz)
1480 				card->pref_erase += card->erase_size - sz;
1481 		}
1482 	} else
1483 		card->pref_erase = 0;
1484 }
1485 
1486 static bool is_trim_arg(unsigned int arg)
1487 {
1488 	return (arg & MMC_TRIM_OR_DISCARD_ARGS) && arg != MMC_DISCARD_ARG;
1489 }
1490 
1491 static unsigned int mmc_mmc_erase_timeout(struct mmc_card *card,
1492 				          unsigned int arg, unsigned int qty)
1493 {
1494 	unsigned int erase_timeout;
1495 
1496 	if (arg == MMC_DISCARD_ARG ||
1497 	    (arg == MMC_TRIM_ARG && card->ext_csd.rev >= 6)) {
1498 		erase_timeout = card->ext_csd.trim_timeout;
1499 	} else if (card->ext_csd.erase_group_def & 1) {
1500 		/* High Capacity Erase Group Size uses HC timeouts */
1501 		if (arg == MMC_TRIM_ARG)
1502 			erase_timeout = card->ext_csd.trim_timeout;
1503 		else
1504 			erase_timeout = card->ext_csd.hc_erase_timeout;
1505 	} else {
1506 		/* CSD Erase Group Size uses write timeout */
1507 		unsigned int mult = (10 << card->csd.r2w_factor);
1508 		unsigned int timeout_clks = card->csd.taac_clks * mult;
1509 		unsigned int timeout_us;
1510 
1511 		/* Avoid overflow: e.g. taac_ns=80000000 mult=1280 */
1512 		if (card->csd.taac_ns < 1000000)
1513 			timeout_us = (card->csd.taac_ns * mult) / 1000;
1514 		else
1515 			timeout_us = (card->csd.taac_ns / 1000) * mult;
1516 
1517 		/*
1518 		 * ios.clock is only a target.  The real clock rate might be
1519 		 * less but not that much less, so fudge it by multiplying by 2.
1520 		 */
1521 		timeout_clks <<= 1;
1522 		timeout_us += (timeout_clks * 1000) /
1523 			      (card->host->ios.clock / 1000);
1524 
1525 		erase_timeout = timeout_us / 1000;
1526 
1527 		/*
1528 		 * Theoretically, the calculation could underflow so round up
1529 		 * to 1ms in that case.
1530 		 */
1531 		if (!erase_timeout)
1532 			erase_timeout = 1;
1533 	}
1534 
1535 	/* Multiplier for secure operations */
1536 	if (arg & MMC_SECURE_ARGS) {
1537 		if (arg == MMC_SECURE_ERASE_ARG)
1538 			erase_timeout *= card->ext_csd.sec_erase_mult;
1539 		else
1540 			erase_timeout *= card->ext_csd.sec_trim_mult;
1541 	}
1542 
1543 	erase_timeout *= qty;
1544 
1545 	/*
1546 	 * Ensure at least a 1 second timeout for SPI as per
1547 	 * 'mmc_set_data_timeout()'
1548 	 */
1549 	if (mmc_host_is_spi(card->host) && erase_timeout < 1000)
1550 		erase_timeout = 1000;
1551 
1552 	return erase_timeout;
1553 }
1554 
1555 static unsigned int mmc_sd_erase_timeout(struct mmc_card *card,
1556 					 unsigned int arg,
1557 					 unsigned int qty)
1558 {
1559 	unsigned int erase_timeout;
1560 
1561 	/* for DISCARD none of the below calculation applies.
1562 	 * the busy timeout is 250msec per discard command.
1563 	 */
1564 	if (arg == SD_DISCARD_ARG)
1565 		return SD_DISCARD_TIMEOUT_MS;
1566 
1567 	if (card->ssr.erase_timeout) {
1568 		/* Erase timeout specified in SD Status Register (SSR) */
1569 		erase_timeout = card->ssr.erase_timeout * qty +
1570 				card->ssr.erase_offset;
1571 	} else {
1572 		/*
1573 		 * Erase timeout not specified in SD Status Register (SSR) so
1574 		 * use 250ms per write block.
1575 		 */
1576 		erase_timeout = 250 * qty;
1577 	}
1578 
1579 	/* Must not be less than 1 second */
1580 	if (erase_timeout < 1000)
1581 		erase_timeout = 1000;
1582 
1583 	return erase_timeout;
1584 }
1585 
1586 static unsigned int mmc_erase_timeout(struct mmc_card *card,
1587 				      unsigned int arg,
1588 				      unsigned int qty)
1589 {
1590 	if (mmc_card_sd(card))
1591 		return mmc_sd_erase_timeout(card, arg, qty);
1592 	else
1593 		return mmc_mmc_erase_timeout(card, arg, qty);
1594 }
1595 
1596 static int mmc_do_erase(struct mmc_card *card, unsigned int from,
1597 			unsigned int to, unsigned int arg)
1598 {
1599 	struct mmc_command cmd = {};
1600 	unsigned int qty = 0, busy_timeout = 0;
1601 	bool use_r1b_resp;
1602 	int err;
1603 
1604 	mmc_retune_hold(card->host);
1605 
1606 	/*
1607 	 * qty is used to calculate the erase timeout which depends on how many
1608 	 * erase groups (or allocation units in SD terminology) are affected.
1609 	 * We count erasing part of an erase group as one erase group.
1610 	 * For SD, the allocation units are always a power of 2.  For MMC, the
1611 	 * erase group size is almost certainly also power of 2, but it does not
1612 	 * seem to insist on that in the JEDEC standard, so we fall back to
1613 	 * division in that case.  SD may not specify an allocation unit size,
1614 	 * in which case the timeout is based on the number of write blocks.
1615 	 *
1616 	 * Note that the timeout for secure trim 2 will only be correct if the
1617 	 * number of erase groups specified is the same as the total of all
1618 	 * preceding secure trim 1 commands.  Since the power may have been
1619 	 * lost since the secure trim 1 commands occurred, it is generally
1620 	 * impossible to calculate the secure trim 2 timeout correctly.
1621 	 */
1622 	if (card->erase_shift)
1623 		qty += ((to >> card->erase_shift) -
1624 			(from >> card->erase_shift)) + 1;
1625 	else if (mmc_card_sd(card))
1626 		qty += to - from + 1;
1627 	else
1628 		qty += ((to / card->erase_size) -
1629 			(from / card->erase_size)) + 1;
1630 
1631 	if (!mmc_card_blockaddr(card)) {
1632 		from <<= 9;
1633 		to <<= 9;
1634 	}
1635 
1636 	if (mmc_card_sd(card))
1637 		cmd.opcode = SD_ERASE_WR_BLK_START;
1638 	else
1639 		cmd.opcode = MMC_ERASE_GROUP_START;
1640 	cmd.arg = from;
1641 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
1642 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
1643 	if (err) {
1644 		pr_err("mmc_erase: group start error %d, "
1645 		       "status %#x\n", err, cmd.resp[0]);
1646 		err = -EIO;
1647 		goto out;
1648 	}
1649 
1650 	memset(&cmd, 0, sizeof(struct mmc_command));
1651 	if (mmc_card_sd(card))
1652 		cmd.opcode = SD_ERASE_WR_BLK_END;
1653 	else
1654 		cmd.opcode = MMC_ERASE_GROUP_END;
1655 	cmd.arg = to;
1656 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
1657 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
1658 	if (err) {
1659 		pr_err("mmc_erase: group end error %d, status %#x\n",
1660 		       err, cmd.resp[0]);
1661 		err = -EIO;
1662 		goto out;
1663 	}
1664 
1665 	memset(&cmd, 0, sizeof(struct mmc_command));
1666 	cmd.opcode = MMC_ERASE;
1667 	cmd.arg = arg;
1668 	busy_timeout = mmc_erase_timeout(card, arg, qty);
1669 	use_r1b_resp = mmc_prepare_busy_cmd(card->host, &cmd, busy_timeout);
1670 
1671 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
1672 	if (err) {
1673 		pr_err("mmc_erase: erase error %d, status %#x\n",
1674 		       err, cmd.resp[0]);
1675 		err = -EIO;
1676 		goto out;
1677 	}
1678 
1679 	if (mmc_host_is_spi(card->host))
1680 		goto out;
1681 
1682 	/*
1683 	 * In case of when R1B + MMC_CAP_WAIT_WHILE_BUSY is used, the polling
1684 	 * shall be avoided.
1685 	 */
1686 	if ((card->host->caps & MMC_CAP_WAIT_WHILE_BUSY) && use_r1b_resp)
1687 		goto out;
1688 
1689 	/* Let's poll to find out when the erase operation completes. */
1690 	err = mmc_poll_for_busy(card, busy_timeout, false, MMC_BUSY_ERASE);
1691 
1692 out:
1693 	mmc_retune_release(card->host);
1694 	return err;
1695 }
1696 
1697 static unsigned int mmc_align_erase_size(struct mmc_card *card,
1698 					 unsigned int *from,
1699 					 unsigned int *to,
1700 					 unsigned int nr)
1701 {
1702 	unsigned int from_new = *from, nr_new = nr, rem;
1703 
1704 	/*
1705 	 * When the 'card->erase_size' is power of 2, we can use round_up/down()
1706 	 * to align the erase size efficiently.
1707 	 */
1708 	if (is_power_of_2(card->erase_size)) {
1709 		unsigned int temp = from_new;
1710 
1711 		from_new = round_up(temp, card->erase_size);
1712 		rem = from_new - temp;
1713 
1714 		if (nr_new > rem)
1715 			nr_new -= rem;
1716 		else
1717 			return 0;
1718 
1719 		nr_new = round_down(nr_new, card->erase_size);
1720 	} else {
1721 		rem = from_new % card->erase_size;
1722 		if (rem) {
1723 			rem = card->erase_size - rem;
1724 			from_new += rem;
1725 			if (nr_new > rem)
1726 				nr_new -= rem;
1727 			else
1728 				return 0;
1729 		}
1730 
1731 		rem = nr_new % card->erase_size;
1732 		if (rem)
1733 			nr_new -= rem;
1734 	}
1735 
1736 	if (nr_new == 0)
1737 		return 0;
1738 
1739 	*to = from_new + nr_new;
1740 	*from = from_new;
1741 
1742 	return nr_new;
1743 }
1744 
1745 /**
1746  * mmc_erase - erase sectors.
1747  * @card: card to erase
1748  * @from: first sector to erase
1749  * @nr: number of sectors to erase
1750  * @arg: erase command argument
1751  *
1752  * Caller must claim host before calling this function.
1753  */
1754 int mmc_erase(struct mmc_card *card, unsigned int from, unsigned int nr,
1755 	      unsigned int arg)
1756 {
1757 	unsigned int rem, to = from + nr;
1758 	int err;
1759 
1760 	if (!(card->csd.cmdclass & CCC_ERASE))
1761 		return -EOPNOTSUPP;
1762 
1763 	if (!card->erase_size)
1764 		return -EOPNOTSUPP;
1765 
1766 	if (mmc_card_sd(card) && arg != SD_ERASE_ARG && arg != SD_DISCARD_ARG)
1767 		return -EOPNOTSUPP;
1768 
1769 	if (mmc_card_mmc(card) && (arg & MMC_SECURE_ARGS) &&
1770 	    !(card->ext_csd.sec_feature_support & EXT_CSD_SEC_ER_EN))
1771 		return -EOPNOTSUPP;
1772 
1773 	if (mmc_card_mmc(card) && is_trim_arg(arg) &&
1774 	    !(card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN))
1775 		return -EOPNOTSUPP;
1776 
1777 	if (arg == MMC_SECURE_ERASE_ARG) {
1778 		if (from % card->erase_size || nr % card->erase_size)
1779 			return -EINVAL;
1780 	}
1781 
1782 	if (arg == MMC_ERASE_ARG)
1783 		nr = mmc_align_erase_size(card, &from, &to, nr);
1784 
1785 	if (nr == 0)
1786 		return 0;
1787 
1788 	if (to <= from)
1789 		return -EINVAL;
1790 
1791 	/* 'from' and 'to' are inclusive */
1792 	to -= 1;
1793 
1794 	/*
1795 	 * Special case where only one erase-group fits in the timeout budget:
1796 	 * If the region crosses an erase-group boundary on this particular
1797 	 * case, we will be trimming more than one erase-group which, does not
1798 	 * fit in the timeout budget of the controller, so we need to split it
1799 	 * and call mmc_do_erase() twice if necessary. This special case is
1800 	 * identified by the card->eg_boundary flag.
1801 	 */
1802 	rem = card->erase_size - (from % card->erase_size);
1803 	if ((arg & MMC_TRIM_OR_DISCARD_ARGS) && card->eg_boundary && nr > rem) {
1804 		err = mmc_do_erase(card, from, from + rem - 1, arg);
1805 		from += rem;
1806 		if ((err) || (to <= from))
1807 			return err;
1808 	}
1809 
1810 	return mmc_do_erase(card, from, to, arg);
1811 }
1812 EXPORT_SYMBOL(mmc_erase);
1813 
1814 int mmc_can_erase(struct mmc_card *card)
1815 {
1816 	if (card->csd.cmdclass & CCC_ERASE && card->erase_size)
1817 		return 1;
1818 	return 0;
1819 }
1820 EXPORT_SYMBOL(mmc_can_erase);
1821 
1822 int mmc_can_trim(struct mmc_card *card)
1823 {
1824 	if ((card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN) &&
1825 	    (!(card->quirks & MMC_QUIRK_TRIM_BROKEN)))
1826 		return 1;
1827 	return 0;
1828 }
1829 EXPORT_SYMBOL(mmc_can_trim);
1830 
1831 int mmc_can_discard(struct mmc_card *card)
1832 {
1833 	/*
1834 	 * As there's no way to detect the discard support bit at v4.5
1835 	 * use the s/w feature support filed.
1836 	 */
1837 	if (card->ext_csd.feature_support & MMC_DISCARD_FEATURE)
1838 		return 1;
1839 	return 0;
1840 }
1841 EXPORT_SYMBOL(mmc_can_discard);
1842 
1843 int mmc_can_sanitize(struct mmc_card *card)
1844 {
1845 	if (!mmc_can_trim(card) && !mmc_can_erase(card))
1846 		return 0;
1847 	if (card->ext_csd.sec_feature_support & EXT_CSD_SEC_SANITIZE)
1848 		return 1;
1849 	return 0;
1850 }
1851 
1852 int mmc_can_secure_erase_trim(struct mmc_card *card)
1853 {
1854 	if ((card->ext_csd.sec_feature_support & EXT_CSD_SEC_ER_EN) &&
1855 	    !(card->quirks & MMC_QUIRK_SEC_ERASE_TRIM_BROKEN))
1856 		return 1;
1857 	return 0;
1858 }
1859 EXPORT_SYMBOL(mmc_can_secure_erase_trim);
1860 
1861 int mmc_erase_group_aligned(struct mmc_card *card, unsigned int from,
1862 			    unsigned int nr)
1863 {
1864 	if (!card->erase_size)
1865 		return 0;
1866 	if (from % card->erase_size || nr % card->erase_size)
1867 		return 0;
1868 	return 1;
1869 }
1870 EXPORT_SYMBOL(mmc_erase_group_aligned);
1871 
1872 static unsigned int mmc_do_calc_max_discard(struct mmc_card *card,
1873 					    unsigned int arg)
1874 {
1875 	struct mmc_host *host = card->host;
1876 	unsigned int max_discard, x, y, qty = 0, max_qty, min_qty, timeout;
1877 	unsigned int last_timeout = 0;
1878 	unsigned int max_busy_timeout = host->max_busy_timeout ?
1879 			host->max_busy_timeout : MMC_ERASE_TIMEOUT_MS;
1880 
1881 	if (card->erase_shift) {
1882 		max_qty = UINT_MAX >> card->erase_shift;
1883 		min_qty = card->pref_erase >> card->erase_shift;
1884 	} else if (mmc_card_sd(card)) {
1885 		max_qty = UINT_MAX;
1886 		min_qty = card->pref_erase;
1887 	} else {
1888 		max_qty = UINT_MAX / card->erase_size;
1889 		min_qty = card->pref_erase / card->erase_size;
1890 	}
1891 
1892 	/*
1893 	 * We should not only use 'host->max_busy_timeout' as the limitation
1894 	 * when deciding the max discard sectors. We should set a balance value
1895 	 * to improve the erase speed, and it can not get too long timeout at
1896 	 * the same time.
1897 	 *
1898 	 * Here we set 'card->pref_erase' as the minimal discard sectors no
1899 	 * matter what size of 'host->max_busy_timeout', but if the
1900 	 * 'host->max_busy_timeout' is large enough for more discard sectors,
1901 	 * then we can continue to increase the max discard sectors until we
1902 	 * get a balance value. In cases when the 'host->max_busy_timeout'
1903 	 * isn't specified, use the default max erase timeout.
1904 	 */
1905 	do {
1906 		y = 0;
1907 		for (x = 1; x && x <= max_qty && max_qty - x >= qty; x <<= 1) {
1908 			timeout = mmc_erase_timeout(card, arg, qty + x);
1909 
1910 			if (qty + x > min_qty && timeout > max_busy_timeout)
1911 				break;
1912 
1913 			if (timeout < last_timeout)
1914 				break;
1915 			last_timeout = timeout;
1916 			y = x;
1917 		}
1918 		qty += y;
1919 	} while (y);
1920 
1921 	if (!qty)
1922 		return 0;
1923 
1924 	/*
1925 	 * When specifying a sector range to trim, chances are we might cross
1926 	 * an erase-group boundary even if the amount of sectors is less than
1927 	 * one erase-group.
1928 	 * If we can only fit one erase-group in the controller timeout budget,
1929 	 * we have to care that erase-group boundaries are not crossed by a
1930 	 * single trim operation. We flag that special case with "eg_boundary".
1931 	 * In all other cases we can just decrement qty and pretend that we
1932 	 * always touch (qty + 1) erase-groups as a simple optimization.
1933 	 */
1934 	if (qty == 1)
1935 		card->eg_boundary = 1;
1936 	else
1937 		qty--;
1938 
1939 	/* Convert qty to sectors */
1940 	if (card->erase_shift)
1941 		max_discard = qty << card->erase_shift;
1942 	else if (mmc_card_sd(card))
1943 		max_discard = qty + 1;
1944 	else
1945 		max_discard = qty * card->erase_size;
1946 
1947 	return max_discard;
1948 }
1949 
1950 unsigned int mmc_calc_max_discard(struct mmc_card *card)
1951 {
1952 	struct mmc_host *host = card->host;
1953 	unsigned int max_discard, max_trim;
1954 
1955 	/*
1956 	 * Without erase_group_def set, MMC erase timeout depends on clock
1957 	 * frequence which can change.  In that case, the best choice is
1958 	 * just the preferred erase size.
1959 	 */
1960 	if (mmc_card_mmc(card) && !(card->ext_csd.erase_group_def & 1))
1961 		return card->pref_erase;
1962 
1963 	max_discard = mmc_do_calc_max_discard(card, MMC_ERASE_ARG);
1964 	if (mmc_can_trim(card)) {
1965 		max_trim = mmc_do_calc_max_discard(card, MMC_TRIM_ARG);
1966 		if (max_trim < max_discard || max_discard == 0)
1967 			max_discard = max_trim;
1968 	} else if (max_discard < card->erase_size) {
1969 		max_discard = 0;
1970 	}
1971 	pr_debug("%s: calculated max. discard sectors %u for timeout %u ms\n",
1972 		mmc_hostname(host), max_discard, host->max_busy_timeout ?
1973 		host->max_busy_timeout : MMC_ERASE_TIMEOUT_MS);
1974 	return max_discard;
1975 }
1976 EXPORT_SYMBOL(mmc_calc_max_discard);
1977 
1978 bool mmc_card_is_blockaddr(struct mmc_card *card)
1979 {
1980 	return card ? mmc_card_blockaddr(card) : false;
1981 }
1982 EXPORT_SYMBOL(mmc_card_is_blockaddr);
1983 
1984 int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen)
1985 {
1986 	struct mmc_command cmd = {};
1987 
1988 	if (mmc_card_blockaddr(card) || mmc_card_ddr52(card) ||
1989 	    mmc_card_hs400(card) || mmc_card_hs400es(card))
1990 		return 0;
1991 
1992 	cmd.opcode = MMC_SET_BLOCKLEN;
1993 	cmd.arg = blocklen;
1994 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
1995 	return mmc_wait_for_cmd(card->host, &cmd, 5);
1996 }
1997 EXPORT_SYMBOL(mmc_set_blocklen);
1998 
1999 static void mmc_hw_reset_for_init(struct mmc_host *host)
2000 {
2001 	mmc_pwrseq_reset(host);
2002 
2003 	if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->card_hw_reset)
2004 		return;
2005 	host->ops->card_hw_reset(host);
2006 }
2007 
2008 /**
2009  * mmc_hw_reset - reset the card in hardware
2010  * @card: card to be reset
2011  *
2012  * Hard reset the card. This function is only for upper layers, like the
2013  * block layer or card drivers. You cannot use it in host drivers (struct
2014  * mmc_card might be gone then).
2015  *
2016  * Return: 0 on success, -errno on failure
2017  */
2018 int mmc_hw_reset(struct mmc_card *card)
2019 {
2020 	struct mmc_host *host = card->host;
2021 	int ret;
2022 
2023 	ret = host->bus_ops->hw_reset(host);
2024 	if (ret < 0)
2025 		pr_warn("%s: tried to HW reset card, got error %d\n",
2026 			mmc_hostname(host), ret);
2027 
2028 	return ret;
2029 }
2030 EXPORT_SYMBOL(mmc_hw_reset);
2031 
2032 int mmc_sw_reset(struct mmc_card *card)
2033 {
2034 	struct mmc_host *host = card->host;
2035 	int ret;
2036 
2037 	if (!host->bus_ops->sw_reset)
2038 		return -EOPNOTSUPP;
2039 
2040 	ret = host->bus_ops->sw_reset(host);
2041 	if (ret)
2042 		pr_warn("%s: tried to SW reset card, got error %d\n",
2043 			mmc_hostname(host), ret);
2044 
2045 	return ret;
2046 }
2047 EXPORT_SYMBOL(mmc_sw_reset);
2048 
2049 static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
2050 {
2051 	host->f_init = freq;
2052 
2053 	pr_debug("%s: %s: trying to init card at %u Hz\n",
2054 		mmc_hostname(host), __func__, host->f_init);
2055 
2056 	mmc_power_up(host, host->ocr_avail);
2057 
2058 	/*
2059 	 * Some eMMCs (with VCCQ always on) may not be reset after power up, so
2060 	 * do a hardware reset if possible.
2061 	 */
2062 	mmc_hw_reset_for_init(host);
2063 
2064 	/*
2065 	 * sdio_reset sends CMD52 to reset card.  Since we do not know
2066 	 * if the card is being re-initialized, just send it.  CMD52
2067 	 * should be ignored by SD/eMMC cards.
2068 	 * Skip it if we already know that we do not support SDIO commands
2069 	 */
2070 	if (!(host->caps2 & MMC_CAP2_NO_SDIO))
2071 		sdio_reset(host);
2072 
2073 	mmc_go_idle(host);
2074 
2075 	if (!(host->caps2 & MMC_CAP2_NO_SD)) {
2076 		if (mmc_send_if_cond_pcie(host, host->ocr_avail))
2077 			goto out;
2078 		if (mmc_card_sd_express(host))
2079 			return 0;
2080 	}
2081 
2082 	/* Order's important: probe SDIO, then SD, then MMC */
2083 	if (!(host->caps2 & MMC_CAP2_NO_SDIO))
2084 		if (!mmc_attach_sdio(host))
2085 			return 0;
2086 
2087 	if (!(host->caps2 & MMC_CAP2_NO_SD))
2088 		if (!mmc_attach_sd(host))
2089 			return 0;
2090 
2091 	if (!(host->caps2 & MMC_CAP2_NO_MMC))
2092 		if (!mmc_attach_mmc(host))
2093 			return 0;
2094 
2095 out:
2096 	mmc_power_off(host);
2097 	return -EIO;
2098 }
2099 
2100 int _mmc_detect_card_removed(struct mmc_host *host)
2101 {
2102 	int ret;
2103 
2104 	if (!host->card || mmc_card_removed(host->card))
2105 		return 1;
2106 
2107 	ret = host->bus_ops->alive(host);
2108 
2109 	/*
2110 	 * Card detect status and alive check may be out of sync if card is
2111 	 * removed slowly, when card detect switch changes while card/slot
2112 	 * pads are still contacted in hardware (refer to "SD Card Mechanical
2113 	 * Addendum, Appendix C: Card Detection Switch"). So reschedule a
2114 	 * detect work 200ms later for this case.
2115 	 */
2116 	if (!ret && host->ops->get_cd && !host->ops->get_cd(host)) {
2117 		mmc_detect_change(host, msecs_to_jiffies(200));
2118 		pr_debug("%s: card removed too slowly\n", mmc_hostname(host));
2119 	}
2120 
2121 	if (ret) {
2122 		mmc_card_set_removed(host->card);
2123 		pr_debug("%s: card remove detected\n", mmc_hostname(host));
2124 	}
2125 
2126 	return ret;
2127 }
2128 
2129 int mmc_detect_card_removed(struct mmc_host *host)
2130 {
2131 	struct mmc_card *card = host->card;
2132 	int ret;
2133 
2134 	WARN_ON(!host->claimed);
2135 
2136 	if (!card)
2137 		return 1;
2138 
2139 	if (!mmc_card_is_removable(host))
2140 		return 0;
2141 
2142 	ret = mmc_card_removed(card);
2143 	/*
2144 	 * The card will be considered unchanged unless we have been asked to
2145 	 * detect a change or host requires polling to provide card detection.
2146 	 */
2147 	if (!host->detect_change && !(host->caps & MMC_CAP_NEEDS_POLL))
2148 		return ret;
2149 
2150 	host->detect_change = 0;
2151 	if (!ret) {
2152 		ret = _mmc_detect_card_removed(host);
2153 		if (ret && (host->caps & MMC_CAP_NEEDS_POLL)) {
2154 			/*
2155 			 * Schedule a detect work as soon as possible to let a
2156 			 * rescan handle the card removal.
2157 			 */
2158 			cancel_delayed_work(&host->detect);
2159 			_mmc_detect_change(host, 0, false);
2160 		}
2161 	}
2162 
2163 	return ret;
2164 }
2165 EXPORT_SYMBOL(mmc_detect_card_removed);
2166 
2167 int mmc_card_alternative_gpt_sector(struct mmc_card *card, sector_t *gpt_sector)
2168 {
2169 	unsigned int boot_sectors_num;
2170 
2171 	if ((!(card->host->caps2 & MMC_CAP2_ALT_GPT_TEGRA)))
2172 		return -EOPNOTSUPP;
2173 
2174 	/* filter out unrelated cards */
2175 	if (card->ext_csd.rev < 3 ||
2176 	    !mmc_card_mmc(card) ||
2177 	    !mmc_card_is_blockaddr(card) ||
2178 	     mmc_card_is_removable(card->host))
2179 		return -ENOENT;
2180 
2181 	/*
2182 	 * eMMC storage has two special boot partitions in addition to the
2183 	 * main one.  NVIDIA's bootloader linearizes eMMC boot0->boot1->main
2184 	 * accesses, this means that the partition table addresses are shifted
2185 	 * by the size of boot partitions.  In accordance with the eMMC
2186 	 * specification, the boot partition size is calculated as follows:
2187 	 *
2188 	 *	boot partition size = 128K byte x BOOT_SIZE_MULT
2189 	 *
2190 	 * Calculate number of sectors occupied by the both boot partitions.
2191 	 */
2192 	boot_sectors_num = card->ext_csd.raw_boot_mult * SZ_128K /
2193 			   SZ_512 * MMC_NUM_BOOT_PARTITION;
2194 
2195 	/* Defined by NVIDIA and used by Android devices. */
2196 	*gpt_sector = card->ext_csd.sectors - boot_sectors_num - 1;
2197 
2198 	return 0;
2199 }
2200 EXPORT_SYMBOL(mmc_card_alternative_gpt_sector);
2201 
2202 static void __mmc_rescan(struct mmc_host *host)
2203 {
2204 	int i;
2205 
2206 	if (host->rescan_disable)
2207 		return;
2208 
2209 	/* If there is a non-removable card registered, only scan once */
2210 	if (!mmc_card_is_removable(host) && host->rescan_entered)
2211 		return;
2212 	host->rescan_entered = 1;
2213 
2214 	if (host->trigger_card_event && host->ops->card_event) {
2215 		mmc_claim_host(host);
2216 		host->ops->card_event(host);
2217 		mmc_release_host(host);
2218 		host->trigger_card_event = false;
2219 	}
2220 
2221 	/* Verify a registered card to be functional, else remove it. */
2222 	if (host->bus_ops)
2223 		host->bus_ops->detect(host);
2224 
2225 	host->detect_change = 0;
2226 
2227 	/* if there still is a card present, stop here */
2228 	if (host->bus_ops != NULL)
2229 		goto out;
2230 
2231 	mmc_claim_host(host);
2232 	if (mmc_card_is_removable(host) && host->ops->get_cd &&
2233 			host->ops->get_cd(host) == 0) {
2234 		mmc_power_off(host);
2235 		mmc_release_host(host);
2236 		goto out;
2237 	}
2238 
2239 	/* If an SD express card is present, then leave it as is. */
2240 	if (mmc_card_sd_express(host)) {
2241 		mmc_release_host(host);
2242 		goto out;
2243 	}
2244 
2245 	for (i = 0; i < ARRAY_SIZE(freqs); i++) {
2246 		unsigned int freq = freqs[i];
2247 		if (freq > host->f_max) {
2248 			if (i + 1 < ARRAY_SIZE(freqs))
2249 				continue;
2250 			freq = host->f_max;
2251 		}
2252 		if (!mmc_rescan_try_freq(host, max(freq, host->f_min)))
2253 			break;
2254 		if (freqs[i] <= host->f_min)
2255 			break;
2256 	}
2257 
2258 	/* A non-removable card should have been detected by now. */
2259 	if (!mmc_card_is_removable(host) && !host->bus_ops)
2260 		pr_info("%s: Failed to initialize a non-removable card",
2261 			mmc_hostname(host));
2262 
2263 	/*
2264 	 * Ignore the command timeout errors observed during
2265 	 * the card init as those are excepted.
2266 	 */
2267 	host->err_stats[MMC_ERR_CMD_TIMEOUT] = 0;
2268 	mmc_release_host(host);
2269 
2270  out:
2271 	if (host->caps & MMC_CAP_NEEDS_POLL)
2272 		mmc_schedule_delayed_work(&host->detect, HZ);
2273 }
2274 
2275 void mmc_rescan(struct work_struct *work)
2276 {
2277 	struct mmc_host *host =
2278 		container_of(work, struct mmc_host, detect.work);
2279 
2280 	__mmc_rescan(host);
2281 }
2282 
2283 void mmc_start_host(struct mmc_host *host)
2284 {
2285 	host->f_init = max(min(freqs[0], host->f_max), host->f_min);
2286 	host->rescan_disable = 0;
2287 
2288 	if (!(host->caps2 & MMC_CAP2_NO_PRESCAN_POWERUP)) {
2289 		mmc_claim_host(host);
2290 		mmc_power_up(host, host->ocr_avail);
2291 		mmc_release_host(host);
2292 	}
2293 
2294 	mmc_gpiod_request_cd_irq(host);
2295 	host->detect_change = 1;
2296 	__mmc_rescan(host);
2297 }
2298 
2299 void __mmc_stop_host(struct mmc_host *host)
2300 {
2301 	if (host->slot.cd_irq >= 0) {
2302 		mmc_gpio_set_cd_wake(host, false);
2303 		disable_irq(host->slot.cd_irq);
2304 	}
2305 
2306 	host->rescan_disable = 1;
2307 	cancel_delayed_work_sync(&host->detect);
2308 }
2309 
2310 void mmc_stop_host(struct mmc_host *host)
2311 {
2312 	__mmc_stop_host(host);
2313 
2314 	/* clear pm flags now and let card drivers set them as needed */
2315 	host->pm_flags = 0;
2316 
2317 	if (host->bus_ops) {
2318 		/* Calling bus_ops->remove() with a claimed host can deadlock */
2319 		host->bus_ops->remove(host);
2320 		mmc_claim_host(host);
2321 		mmc_detach_bus(host);
2322 		mmc_power_off(host);
2323 		mmc_release_host(host);
2324 		return;
2325 	}
2326 
2327 	mmc_claim_host(host);
2328 	mmc_power_off(host);
2329 	mmc_release_host(host);
2330 }
2331 
2332 static int __init mmc_init(void)
2333 {
2334 	int ret;
2335 
2336 	ret = mmc_register_bus();
2337 	if (ret)
2338 		return ret;
2339 
2340 	ret = mmc_register_host_class();
2341 	if (ret)
2342 		goto unregister_bus;
2343 
2344 	ret = sdio_register_bus();
2345 	if (ret)
2346 		goto unregister_host_class;
2347 
2348 	return 0;
2349 
2350 unregister_host_class:
2351 	mmc_unregister_host_class();
2352 unregister_bus:
2353 	mmc_unregister_bus();
2354 	return ret;
2355 }
2356 
2357 static void __exit mmc_exit(void)
2358 {
2359 	sdio_unregister_bus();
2360 	mmc_unregister_host_class();
2361 	mmc_unregister_bus();
2362 }
2363 
2364 subsys_initcall(mmc_init);
2365 module_exit(mmc_exit);
2366 
2367 MODULE_LICENSE("GPL");
2368