xref: /openbmc/linux/drivers/mmc/core/core.c (revision f7af616c)
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 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[prandom_u32() % ARRAY_SIZE(data_errors)];
101 	data->bytes_xfered = (prandom_u32() % (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 (cmd->opcode != MMC_SEND_TUNING_BLOCK &&
146 	    cmd->opcode != MMC_SEND_TUNING_BLOCK_HS200 &&
147 	    !host->retune_crc_disable &&
148 	    (err == -EILSEQ || (mrq->sbc && mrq->sbc->error == -EILSEQ) ||
149 	    (mrq->data && mrq->data->error == -EILSEQ) ||
150 	    (mrq->stop && mrq->stop->error == -EILSEQ)))
151 		mmc_retune_needed(host);
152 
153 	if (err && cmd->retries && mmc_host_is_spi(host)) {
154 		if (cmd->resp[0] & R1_SPI_ILLEGAL_COMMAND)
155 			cmd->retries = 0;
156 	}
157 
158 	if (host->ongoing_mrq == mrq)
159 		host->ongoing_mrq = NULL;
160 
161 	mmc_complete_cmd(mrq);
162 
163 	trace_mmc_request_done(host, mrq);
164 
165 	/*
166 	 * We list various conditions for the command to be considered
167 	 * properly done:
168 	 *
169 	 * - There was no error, OK fine then
170 	 * - We are not doing some kind of retry
171 	 * - The card was removed (...so just complete everything no matter
172 	 *   if there are errors or retries)
173 	 */
174 	if (!err || !cmd->retries || mmc_card_removed(host->card)) {
175 		mmc_should_fail_request(host, mrq);
176 
177 		if (!host->ongoing_mrq)
178 			led_trigger_event(host->led, LED_OFF);
179 
180 		if (mrq->sbc) {
181 			pr_debug("%s: req done <CMD%u>: %d: %08x %08x %08x %08x\n",
182 				mmc_hostname(host), mrq->sbc->opcode,
183 				mrq->sbc->error,
184 				mrq->sbc->resp[0], mrq->sbc->resp[1],
185 				mrq->sbc->resp[2], mrq->sbc->resp[3]);
186 		}
187 
188 		pr_debug("%s: req done (CMD%u): %d: %08x %08x %08x %08x\n",
189 			mmc_hostname(host), cmd->opcode, err,
190 			cmd->resp[0], cmd->resp[1],
191 			cmd->resp[2], cmd->resp[3]);
192 
193 		if (mrq->data) {
194 			pr_debug("%s:     %d bytes transferred: %d\n",
195 				mmc_hostname(host),
196 				mrq->data->bytes_xfered, mrq->data->error);
197 		}
198 
199 		if (mrq->stop) {
200 			pr_debug("%s:     (CMD%u): %d: %08x %08x %08x %08x\n",
201 				mmc_hostname(host), mrq->stop->opcode,
202 				mrq->stop->error,
203 				mrq->stop->resp[0], mrq->stop->resp[1],
204 				mrq->stop->resp[2], mrq->stop->resp[3]);
205 		}
206 	}
207 	/*
208 	 * Request starter must handle retries - see
209 	 * mmc_wait_for_req_done().
210 	 */
211 	if (mrq->done)
212 		mrq->done(mrq);
213 }
214 
215 EXPORT_SYMBOL(mmc_request_done);
216 
217 static void __mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
218 {
219 	int err;
220 
221 	/* Assumes host controller has been runtime resumed by mmc_claim_host */
222 	err = mmc_retune(host);
223 	if (err) {
224 		mrq->cmd->error = err;
225 		mmc_request_done(host, mrq);
226 		return;
227 	}
228 
229 	/*
230 	 * For sdio rw commands we must wait for card busy otherwise some
231 	 * sdio devices won't work properly.
232 	 * And bypass I/O abort, reset and bus suspend operations.
233 	 */
234 	if (sdio_is_io_busy(mrq->cmd->opcode, mrq->cmd->arg) &&
235 	    host->ops->card_busy) {
236 		int tries = 500; /* Wait aprox 500ms at maximum */
237 
238 		while (host->ops->card_busy(host) && --tries)
239 			mmc_delay(1);
240 
241 		if (tries == 0) {
242 			mrq->cmd->error = -EBUSY;
243 			mmc_request_done(host, mrq);
244 			return;
245 		}
246 	}
247 
248 	if (mrq->cap_cmd_during_tfr) {
249 		host->ongoing_mrq = mrq;
250 		/*
251 		 * Retry path could come through here without having waiting on
252 		 * cmd_completion, so ensure it is reinitialised.
253 		 */
254 		reinit_completion(&mrq->cmd_completion);
255 	}
256 
257 	trace_mmc_request_start(host, mrq);
258 
259 	if (host->cqe_on)
260 		host->cqe_ops->cqe_off(host);
261 
262 	host->ops->request(host, mrq);
263 }
264 
265 static void mmc_mrq_pr_debug(struct mmc_host *host, struct mmc_request *mrq,
266 			     bool cqe)
267 {
268 	if (mrq->sbc) {
269 		pr_debug("<%s: starting CMD%u arg %08x flags %08x>\n",
270 			 mmc_hostname(host), mrq->sbc->opcode,
271 			 mrq->sbc->arg, mrq->sbc->flags);
272 	}
273 
274 	if (mrq->cmd) {
275 		pr_debug("%s: starting %sCMD%u arg %08x flags %08x\n",
276 			 mmc_hostname(host), cqe ? "CQE direct " : "",
277 			 mrq->cmd->opcode, mrq->cmd->arg, mrq->cmd->flags);
278 	} else if (cqe) {
279 		pr_debug("%s: starting CQE transfer for tag %d blkaddr %u\n",
280 			 mmc_hostname(host), mrq->tag, mrq->data->blk_addr);
281 	}
282 
283 	if (mrq->data) {
284 		pr_debug("%s:     blksz %d blocks %d flags %08x "
285 			"tsac %d ms nsac %d\n",
286 			mmc_hostname(host), mrq->data->blksz,
287 			mrq->data->blocks, mrq->data->flags,
288 			mrq->data->timeout_ns / 1000000,
289 			mrq->data->timeout_clks);
290 	}
291 
292 	if (mrq->stop) {
293 		pr_debug("%s:     CMD%u arg %08x flags %08x\n",
294 			 mmc_hostname(host), mrq->stop->opcode,
295 			 mrq->stop->arg, mrq->stop->flags);
296 	}
297 }
298 
299 static int mmc_mrq_prep(struct mmc_host *host, struct mmc_request *mrq)
300 {
301 	unsigned int i, sz = 0;
302 	struct scatterlist *sg;
303 
304 	if (mrq->cmd) {
305 		mrq->cmd->error = 0;
306 		mrq->cmd->mrq = mrq;
307 		mrq->cmd->data = mrq->data;
308 	}
309 	if (mrq->sbc) {
310 		mrq->sbc->error = 0;
311 		mrq->sbc->mrq = mrq;
312 	}
313 	if (mrq->data) {
314 		if (mrq->data->blksz > host->max_blk_size ||
315 		    mrq->data->blocks > host->max_blk_count ||
316 		    mrq->data->blocks * mrq->data->blksz > host->max_req_size)
317 			return -EINVAL;
318 
319 		for_each_sg(mrq->data->sg, sg, mrq->data->sg_len, i)
320 			sz += sg->length;
321 		if (sz != mrq->data->blocks * mrq->data->blksz)
322 			return -EINVAL;
323 
324 		mrq->data->error = 0;
325 		mrq->data->mrq = mrq;
326 		if (mrq->stop) {
327 			mrq->data->stop = mrq->stop;
328 			mrq->stop->error = 0;
329 			mrq->stop->mrq = mrq;
330 		}
331 	}
332 
333 	return 0;
334 }
335 
336 int mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
337 {
338 	int err;
339 
340 	init_completion(&mrq->cmd_completion);
341 
342 	mmc_retune_hold(host);
343 
344 	if (mmc_card_removed(host->card))
345 		return -ENOMEDIUM;
346 
347 	mmc_mrq_pr_debug(host, mrq, false);
348 
349 	WARN_ON(!host->claimed);
350 
351 	err = mmc_mrq_prep(host, mrq);
352 	if (err)
353 		return err;
354 
355 	led_trigger_event(host->led, LED_FULL);
356 	__mmc_start_request(host, mrq);
357 
358 	return 0;
359 }
360 EXPORT_SYMBOL(mmc_start_request);
361 
362 static void mmc_wait_done(struct mmc_request *mrq)
363 {
364 	complete(&mrq->completion);
365 }
366 
367 static inline void mmc_wait_ongoing_tfr_cmd(struct mmc_host *host)
368 {
369 	struct mmc_request *ongoing_mrq = READ_ONCE(host->ongoing_mrq);
370 
371 	/*
372 	 * If there is an ongoing transfer, wait for the command line to become
373 	 * available.
374 	 */
375 	if (ongoing_mrq && !completion_done(&ongoing_mrq->cmd_completion))
376 		wait_for_completion(&ongoing_mrq->cmd_completion);
377 }
378 
379 static int __mmc_start_req(struct mmc_host *host, struct mmc_request *mrq)
380 {
381 	int err;
382 
383 	mmc_wait_ongoing_tfr_cmd(host);
384 
385 	init_completion(&mrq->completion);
386 	mrq->done = mmc_wait_done;
387 
388 	err = mmc_start_request(host, mrq);
389 	if (err) {
390 		mrq->cmd->error = err;
391 		mmc_complete_cmd(mrq);
392 		complete(&mrq->completion);
393 	}
394 
395 	return err;
396 }
397 
398 void mmc_wait_for_req_done(struct mmc_host *host, struct mmc_request *mrq)
399 {
400 	struct mmc_command *cmd;
401 
402 	while (1) {
403 		wait_for_completion(&mrq->completion);
404 
405 		cmd = mrq->cmd;
406 
407 		if (!cmd->error || !cmd->retries ||
408 		    mmc_card_removed(host->card))
409 			break;
410 
411 		mmc_retune_recheck(host);
412 
413 		pr_debug("%s: req failed (CMD%u): %d, retrying...\n",
414 			 mmc_hostname(host), cmd->opcode, cmd->error);
415 		cmd->retries--;
416 		cmd->error = 0;
417 		__mmc_start_request(host, mrq);
418 	}
419 
420 	mmc_retune_release(host);
421 }
422 EXPORT_SYMBOL(mmc_wait_for_req_done);
423 
424 /*
425  * mmc_cqe_start_req - Start a CQE request.
426  * @host: MMC host to start the request
427  * @mrq: request to start
428  *
429  * Start the request, re-tuning if needed and it is possible. Returns an error
430  * code if the request fails to start or -EBUSY if CQE is busy.
431  */
432 int mmc_cqe_start_req(struct mmc_host *host, struct mmc_request *mrq)
433 {
434 	int err;
435 
436 	/*
437 	 * CQE cannot process re-tuning commands. Caller must hold retuning
438 	 * while CQE is in use.  Re-tuning can happen here only when CQE has no
439 	 * active requests i.e. this is the first.  Note, re-tuning will call
440 	 * ->cqe_off().
441 	 */
442 	err = mmc_retune(host);
443 	if (err)
444 		goto out_err;
445 
446 	mrq->host = host;
447 
448 	mmc_mrq_pr_debug(host, mrq, true);
449 
450 	err = mmc_mrq_prep(host, mrq);
451 	if (err)
452 		goto out_err;
453 
454 	err = host->cqe_ops->cqe_request(host, mrq);
455 	if (err)
456 		goto out_err;
457 
458 	trace_mmc_request_start(host, mrq);
459 
460 	return 0;
461 
462 out_err:
463 	if (mrq->cmd) {
464 		pr_debug("%s: failed to start CQE direct CMD%u, error %d\n",
465 			 mmc_hostname(host), mrq->cmd->opcode, err);
466 	} else {
467 		pr_debug("%s: failed to start CQE transfer for tag %d, error %d\n",
468 			 mmc_hostname(host), mrq->tag, err);
469 	}
470 	return err;
471 }
472 EXPORT_SYMBOL(mmc_cqe_start_req);
473 
474 /**
475  *	mmc_cqe_request_done - CQE has finished processing an MMC request
476  *	@host: MMC host which completed request
477  *	@mrq: MMC request which completed
478  *
479  *	CQE drivers should call this function when they have completed
480  *	their processing of a request.
481  */
482 void mmc_cqe_request_done(struct mmc_host *host, struct mmc_request *mrq)
483 {
484 	mmc_should_fail_request(host, mrq);
485 
486 	/* Flag re-tuning needed on CRC errors */
487 	if ((mrq->cmd && mrq->cmd->error == -EILSEQ) ||
488 	    (mrq->data && mrq->data->error == -EILSEQ))
489 		mmc_retune_needed(host);
490 
491 	trace_mmc_request_done(host, mrq);
492 
493 	if (mrq->cmd) {
494 		pr_debug("%s: CQE req done (direct CMD%u): %d\n",
495 			 mmc_hostname(host), mrq->cmd->opcode, mrq->cmd->error);
496 	} else {
497 		pr_debug("%s: CQE transfer done tag %d\n",
498 			 mmc_hostname(host), mrq->tag);
499 	}
500 
501 	if (mrq->data) {
502 		pr_debug("%s:     %d bytes transferred: %d\n",
503 			 mmc_hostname(host),
504 			 mrq->data->bytes_xfered, mrq->data->error);
505 	}
506 
507 	mrq->done(mrq);
508 }
509 EXPORT_SYMBOL(mmc_cqe_request_done);
510 
511 /**
512  *	mmc_cqe_post_req - CQE post process of a completed MMC request
513  *	@host: MMC host
514  *	@mrq: MMC request to be processed
515  */
516 void mmc_cqe_post_req(struct mmc_host *host, struct mmc_request *mrq)
517 {
518 	if (host->cqe_ops->cqe_post_req)
519 		host->cqe_ops->cqe_post_req(host, mrq);
520 }
521 EXPORT_SYMBOL(mmc_cqe_post_req);
522 
523 /* Arbitrary 1 second timeout */
524 #define MMC_CQE_RECOVERY_TIMEOUT	1000
525 
526 /*
527  * mmc_cqe_recovery - Recover from CQE errors.
528  * @host: MMC host to recover
529  *
530  * Recovery consists of stopping CQE, stopping eMMC, discarding the queue in
531  * in eMMC, and discarding the queue in CQE. CQE must call
532  * mmc_cqe_request_done() on all requests. An error is returned if the eMMC
533  * fails to discard its queue.
534  */
535 int mmc_cqe_recovery(struct mmc_host *host)
536 {
537 	struct mmc_command cmd;
538 	int err;
539 
540 	mmc_retune_hold_now(host);
541 
542 	/*
543 	 * Recovery is expected seldom, if at all, but it reduces performance,
544 	 * so make sure it is not completely silent.
545 	 */
546 	pr_warn("%s: running CQE recovery\n", mmc_hostname(host));
547 
548 	host->cqe_ops->cqe_recovery_start(host);
549 
550 	memset(&cmd, 0, sizeof(cmd));
551 	cmd.opcode       = MMC_STOP_TRANSMISSION;
552 	cmd.flags        = MMC_RSP_R1B | MMC_CMD_AC;
553 	cmd.flags       &= ~MMC_RSP_CRC; /* Ignore CRC */
554 	cmd.busy_timeout = MMC_CQE_RECOVERY_TIMEOUT;
555 	mmc_wait_for_cmd(host, &cmd, 0);
556 
557 	memset(&cmd, 0, sizeof(cmd));
558 	cmd.opcode       = MMC_CMDQ_TASK_MGMT;
559 	cmd.arg          = 1; /* Discard entire queue */
560 	cmd.flags        = MMC_RSP_R1B | MMC_CMD_AC;
561 	cmd.flags       &= ~MMC_RSP_CRC; /* Ignore CRC */
562 	cmd.busy_timeout = MMC_CQE_RECOVERY_TIMEOUT;
563 	err = mmc_wait_for_cmd(host, &cmd, 0);
564 
565 	host->cqe_ops->cqe_recovery_finish(host);
566 
567 	mmc_retune_release(host);
568 
569 	return err;
570 }
571 EXPORT_SYMBOL(mmc_cqe_recovery);
572 
573 /**
574  *	mmc_is_req_done - Determine if a 'cap_cmd_during_tfr' request is done
575  *	@host: MMC host
576  *	@mrq: MMC request
577  *
578  *	mmc_is_req_done() is used with requests that have
579  *	mrq->cap_cmd_during_tfr = true. mmc_is_req_done() must be called after
580  *	starting a request and before waiting for it to complete. That is,
581  *	either in between calls to mmc_start_req(), or after mmc_wait_for_req()
582  *	and before mmc_wait_for_req_done(). If it is called at other times the
583  *	result is not meaningful.
584  */
585 bool mmc_is_req_done(struct mmc_host *host, struct mmc_request *mrq)
586 {
587 	return completion_done(&mrq->completion);
588 }
589 EXPORT_SYMBOL(mmc_is_req_done);
590 
591 /**
592  *	mmc_wait_for_req - start a request and wait for completion
593  *	@host: MMC host to start command
594  *	@mrq: MMC request to start
595  *
596  *	Start a new MMC custom command request for a host, and wait
597  *	for the command to complete. In the case of 'cap_cmd_during_tfr'
598  *	requests, the transfer is ongoing and the caller can issue further
599  *	commands that do not use the data lines, and then wait by calling
600  *	mmc_wait_for_req_done().
601  *	Does not attempt to parse the response.
602  */
603 void mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq)
604 {
605 	__mmc_start_req(host, mrq);
606 
607 	if (!mrq->cap_cmd_during_tfr)
608 		mmc_wait_for_req_done(host, mrq);
609 }
610 EXPORT_SYMBOL(mmc_wait_for_req);
611 
612 /**
613  *	mmc_wait_for_cmd - start a command and wait for completion
614  *	@host: MMC host to start command
615  *	@cmd: MMC command to start
616  *	@retries: maximum number of retries
617  *
618  *	Start a new MMC command for a host, and wait for the command
619  *	to complete.  Return any error that occurred while the command
620  *	was executing.  Do not attempt to parse the response.
621  */
622 int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries)
623 {
624 	struct mmc_request mrq = {};
625 
626 	WARN_ON(!host->claimed);
627 
628 	memset(cmd->resp, 0, sizeof(cmd->resp));
629 	cmd->retries = retries;
630 
631 	mrq.cmd = cmd;
632 	cmd->data = NULL;
633 
634 	mmc_wait_for_req(host, &mrq);
635 
636 	return cmd->error;
637 }
638 
639 EXPORT_SYMBOL(mmc_wait_for_cmd);
640 
641 /**
642  *	mmc_set_data_timeout - set the timeout for a data command
643  *	@data: data phase for command
644  *	@card: the MMC card associated with the data transfer
645  *
646  *	Computes the data timeout parameters according to the
647  *	correct algorithm given the card type.
648  */
649 void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card)
650 {
651 	unsigned int mult;
652 
653 	/*
654 	 * SDIO cards only define an upper 1 s limit on access.
655 	 */
656 	if (mmc_card_sdio(card)) {
657 		data->timeout_ns = 1000000000;
658 		data->timeout_clks = 0;
659 		return;
660 	}
661 
662 	/*
663 	 * SD cards use a 100 multiplier rather than 10
664 	 */
665 	mult = mmc_card_sd(card) ? 100 : 10;
666 
667 	/*
668 	 * Scale up the multiplier (and therefore the timeout) by
669 	 * the r2w factor for writes.
670 	 */
671 	if (data->flags & MMC_DATA_WRITE)
672 		mult <<= card->csd.r2w_factor;
673 
674 	data->timeout_ns = card->csd.taac_ns * mult;
675 	data->timeout_clks = card->csd.taac_clks * mult;
676 
677 	/*
678 	 * SD cards also have an upper limit on the timeout.
679 	 */
680 	if (mmc_card_sd(card)) {
681 		unsigned int timeout_us, limit_us;
682 
683 		timeout_us = data->timeout_ns / 1000;
684 		if (card->host->ios.clock)
685 			timeout_us += data->timeout_clks * 1000 /
686 				(card->host->ios.clock / 1000);
687 
688 		if (data->flags & MMC_DATA_WRITE)
689 			/*
690 			 * The MMC spec "It is strongly recommended
691 			 * for hosts to implement more than 500ms
692 			 * timeout value even if the card indicates
693 			 * the 250ms maximum busy length."  Even the
694 			 * previous value of 300ms is known to be
695 			 * insufficient for some cards.
696 			 */
697 			limit_us = 3000000;
698 		else
699 			limit_us = 100000;
700 
701 		/*
702 		 * SDHC cards always use these fixed values.
703 		 */
704 		if (timeout_us > limit_us) {
705 			data->timeout_ns = limit_us * 1000;
706 			data->timeout_clks = 0;
707 		}
708 
709 		/* assign limit value if invalid */
710 		if (timeout_us == 0)
711 			data->timeout_ns = limit_us * 1000;
712 	}
713 
714 	/*
715 	 * Some cards require longer data read timeout than indicated in CSD.
716 	 * Address this by setting the read timeout to a "reasonably high"
717 	 * value. For the cards tested, 600ms has proven enough. If necessary,
718 	 * this value can be increased if other problematic cards require this.
719 	 */
720 	if (mmc_card_long_read_time(card) && data->flags & MMC_DATA_READ) {
721 		data->timeout_ns = 600000000;
722 		data->timeout_clks = 0;
723 	}
724 
725 	/*
726 	 * Some cards need very high timeouts if driven in SPI mode.
727 	 * The worst observed timeout was 900ms after writing a
728 	 * continuous stream of data until the internal logic
729 	 * overflowed.
730 	 */
731 	if (mmc_host_is_spi(card->host)) {
732 		if (data->flags & MMC_DATA_WRITE) {
733 			if (data->timeout_ns < 1000000000)
734 				data->timeout_ns = 1000000000;	/* 1s */
735 		} else {
736 			if (data->timeout_ns < 100000000)
737 				data->timeout_ns =  100000000;	/* 100ms */
738 		}
739 	}
740 }
741 EXPORT_SYMBOL(mmc_set_data_timeout);
742 
743 /*
744  * Allow claiming an already claimed host if the context is the same or there is
745  * no context but the task is the same.
746  */
747 static inline bool mmc_ctx_matches(struct mmc_host *host, struct mmc_ctx *ctx,
748 				   struct task_struct *task)
749 {
750 	return host->claimer == ctx ||
751 	       (!ctx && task && host->claimer->task == task);
752 }
753 
754 static inline void mmc_ctx_set_claimer(struct mmc_host *host,
755 				       struct mmc_ctx *ctx,
756 				       struct task_struct *task)
757 {
758 	if (!host->claimer) {
759 		if (ctx)
760 			host->claimer = ctx;
761 		else
762 			host->claimer = &host->default_ctx;
763 	}
764 	if (task)
765 		host->claimer->task = task;
766 }
767 
768 /**
769  *	__mmc_claim_host - exclusively claim a host
770  *	@host: mmc host to claim
771  *	@ctx: context that claims the host or NULL in which case the default
772  *	context will be used
773  *	@abort: whether or not the operation should be aborted
774  *
775  *	Claim a host for a set of operations.  If @abort is non null and
776  *	dereference a non-zero value then this will return prematurely with
777  *	that non-zero value without acquiring the lock.  Returns zero
778  *	with the lock held otherwise.
779  */
780 int __mmc_claim_host(struct mmc_host *host, struct mmc_ctx *ctx,
781 		     atomic_t *abort)
782 {
783 	struct task_struct *task = ctx ? NULL : current;
784 	DECLARE_WAITQUEUE(wait, current);
785 	unsigned long flags;
786 	int stop;
787 	bool pm = false;
788 
789 	might_sleep();
790 
791 	add_wait_queue(&host->wq, &wait);
792 	spin_lock_irqsave(&host->lock, flags);
793 	while (1) {
794 		set_current_state(TASK_UNINTERRUPTIBLE);
795 		stop = abort ? atomic_read(abort) : 0;
796 		if (stop || !host->claimed || mmc_ctx_matches(host, ctx, task))
797 			break;
798 		spin_unlock_irqrestore(&host->lock, flags);
799 		schedule();
800 		spin_lock_irqsave(&host->lock, flags);
801 	}
802 	set_current_state(TASK_RUNNING);
803 	if (!stop) {
804 		host->claimed = 1;
805 		mmc_ctx_set_claimer(host, ctx, task);
806 		host->claim_cnt += 1;
807 		if (host->claim_cnt == 1)
808 			pm = true;
809 	} else
810 		wake_up(&host->wq);
811 	spin_unlock_irqrestore(&host->lock, flags);
812 	remove_wait_queue(&host->wq, &wait);
813 
814 	if (pm)
815 		pm_runtime_get_sync(mmc_dev(host));
816 
817 	return stop;
818 }
819 EXPORT_SYMBOL(__mmc_claim_host);
820 
821 /**
822  *	mmc_release_host - release a host
823  *	@host: mmc host to release
824  *
825  *	Release a MMC host, allowing others to claim the host
826  *	for their operations.
827  */
828 void mmc_release_host(struct mmc_host *host)
829 {
830 	unsigned long flags;
831 
832 	WARN_ON(!host->claimed);
833 
834 	spin_lock_irqsave(&host->lock, flags);
835 	if (--host->claim_cnt) {
836 		/* Release for nested claim */
837 		spin_unlock_irqrestore(&host->lock, flags);
838 	} else {
839 		host->claimed = 0;
840 		host->claimer->task = NULL;
841 		host->claimer = NULL;
842 		spin_unlock_irqrestore(&host->lock, flags);
843 		wake_up(&host->wq);
844 		pm_runtime_mark_last_busy(mmc_dev(host));
845 		if (host->caps & MMC_CAP_SYNC_RUNTIME_PM)
846 			pm_runtime_put_sync_suspend(mmc_dev(host));
847 		else
848 			pm_runtime_put_autosuspend(mmc_dev(host));
849 	}
850 }
851 EXPORT_SYMBOL(mmc_release_host);
852 
853 /*
854  * This is a helper function, which fetches a runtime pm reference for the
855  * card device and also claims the host.
856  */
857 void mmc_get_card(struct mmc_card *card, struct mmc_ctx *ctx)
858 {
859 	pm_runtime_get_sync(&card->dev);
860 	__mmc_claim_host(card->host, ctx, NULL);
861 }
862 EXPORT_SYMBOL(mmc_get_card);
863 
864 /*
865  * This is a helper function, which releases the host and drops the runtime
866  * pm reference for the card device.
867  */
868 void mmc_put_card(struct mmc_card *card, struct mmc_ctx *ctx)
869 {
870 	struct mmc_host *host = card->host;
871 
872 	WARN_ON(ctx && host->claimer != ctx);
873 
874 	mmc_release_host(host);
875 	pm_runtime_mark_last_busy(&card->dev);
876 	pm_runtime_put_autosuspend(&card->dev);
877 }
878 EXPORT_SYMBOL(mmc_put_card);
879 
880 /*
881  * Internal function that does the actual ios call to the host driver,
882  * optionally printing some debug output.
883  */
884 static inline void mmc_set_ios(struct mmc_host *host)
885 {
886 	struct mmc_ios *ios = &host->ios;
887 
888 	pr_debug("%s: clock %uHz busmode %u powermode %u cs %u Vdd %u "
889 		"width %u timing %u\n",
890 		 mmc_hostname(host), ios->clock, ios->bus_mode,
891 		 ios->power_mode, ios->chip_select, ios->vdd,
892 		 1 << ios->bus_width, ios->timing);
893 
894 	host->ops->set_ios(host, ios);
895 }
896 
897 /*
898  * Control chip select pin on a host.
899  */
900 void mmc_set_chip_select(struct mmc_host *host, int mode)
901 {
902 	host->ios.chip_select = mode;
903 	mmc_set_ios(host);
904 }
905 
906 /*
907  * Sets the host clock to the highest possible frequency that
908  * is below "hz".
909  */
910 void mmc_set_clock(struct mmc_host *host, unsigned int hz)
911 {
912 	WARN_ON(hz && hz < host->f_min);
913 
914 	if (hz > host->f_max)
915 		hz = host->f_max;
916 
917 	host->ios.clock = hz;
918 	mmc_set_ios(host);
919 }
920 
921 int mmc_execute_tuning(struct mmc_card *card)
922 {
923 	struct mmc_host *host = card->host;
924 	u32 opcode;
925 	int err;
926 
927 	if (!host->ops->execute_tuning)
928 		return 0;
929 
930 	if (host->cqe_on)
931 		host->cqe_ops->cqe_off(host);
932 
933 	if (mmc_card_mmc(card))
934 		opcode = MMC_SEND_TUNING_BLOCK_HS200;
935 	else
936 		opcode = MMC_SEND_TUNING_BLOCK;
937 
938 	err = host->ops->execute_tuning(host, opcode);
939 
940 	if (err)
941 		pr_err("%s: tuning execution failed: %d\n",
942 			mmc_hostname(host), err);
943 	else
944 		mmc_retune_enable(host);
945 
946 	return err;
947 }
948 
949 /*
950  * Change the bus mode (open drain/push-pull) of a host.
951  */
952 void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode)
953 {
954 	host->ios.bus_mode = mode;
955 	mmc_set_ios(host);
956 }
957 
958 /*
959  * Change data bus width of a host.
960  */
961 void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
962 {
963 	host->ios.bus_width = width;
964 	mmc_set_ios(host);
965 }
966 
967 /*
968  * Set initial state after a power cycle or a hw_reset.
969  */
970 void mmc_set_initial_state(struct mmc_host *host)
971 {
972 	if (host->cqe_on)
973 		host->cqe_ops->cqe_off(host);
974 
975 	mmc_retune_disable(host);
976 
977 	if (mmc_host_is_spi(host))
978 		host->ios.chip_select = MMC_CS_HIGH;
979 	else
980 		host->ios.chip_select = MMC_CS_DONTCARE;
981 	host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
982 	host->ios.bus_width = MMC_BUS_WIDTH_1;
983 	host->ios.timing = MMC_TIMING_LEGACY;
984 	host->ios.drv_type = 0;
985 	host->ios.enhanced_strobe = false;
986 
987 	/*
988 	 * Make sure we are in non-enhanced strobe mode before we
989 	 * actually enable it in ext_csd.
990 	 */
991 	if ((host->caps2 & MMC_CAP2_HS400_ES) &&
992 	     host->ops->hs400_enhanced_strobe)
993 		host->ops->hs400_enhanced_strobe(host, &host->ios);
994 
995 	mmc_set_ios(host);
996 
997 	mmc_crypto_set_initial_state(host);
998 }
999 
1000 /**
1001  * mmc_vdd_to_ocrbitnum - Convert a voltage to the OCR bit number
1002  * @vdd:	voltage (mV)
1003  * @low_bits:	prefer low bits in boundary cases
1004  *
1005  * This function returns the OCR bit number according to the provided @vdd
1006  * value. If conversion is not possible a negative errno value returned.
1007  *
1008  * Depending on the @low_bits flag the function prefers low or high OCR bits
1009  * on boundary voltages. For example,
1010  * with @low_bits = true, 3300 mV translates to ilog2(MMC_VDD_32_33);
1011  * with @low_bits = false, 3300 mV translates to ilog2(MMC_VDD_33_34);
1012  *
1013  * Any value in the [1951:1999] range translates to the ilog2(MMC_VDD_20_21).
1014  */
1015 static int mmc_vdd_to_ocrbitnum(int vdd, bool low_bits)
1016 {
1017 	const int max_bit = ilog2(MMC_VDD_35_36);
1018 	int bit;
1019 
1020 	if (vdd < 1650 || vdd > 3600)
1021 		return -EINVAL;
1022 
1023 	if (vdd >= 1650 && vdd <= 1950)
1024 		return ilog2(MMC_VDD_165_195);
1025 
1026 	if (low_bits)
1027 		vdd -= 1;
1028 
1029 	/* Base 2000 mV, step 100 mV, bit's base 8. */
1030 	bit = (vdd - 2000) / 100 + 8;
1031 	if (bit > max_bit)
1032 		return max_bit;
1033 	return bit;
1034 }
1035 
1036 /**
1037  * mmc_vddrange_to_ocrmask - Convert a voltage range to the OCR mask
1038  * @vdd_min:	minimum voltage value (mV)
1039  * @vdd_max:	maximum voltage value (mV)
1040  *
1041  * This function returns the OCR mask bits according to the provided @vdd_min
1042  * and @vdd_max values. If conversion is not possible the function returns 0.
1043  *
1044  * Notes wrt boundary cases:
1045  * This function sets the OCR bits for all boundary voltages, for example
1046  * [3300:3400] range is translated to MMC_VDD_32_33 | MMC_VDD_33_34 |
1047  * MMC_VDD_34_35 mask.
1048  */
1049 u32 mmc_vddrange_to_ocrmask(int vdd_min, int vdd_max)
1050 {
1051 	u32 mask = 0;
1052 
1053 	if (vdd_max < vdd_min)
1054 		return 0;
1055 
1056 	/* Prefer high bits for the boundary vdd_max values. */
1057 	vdd_max = mmc_vdd_to_ocrbitnum(vdd_max, false);
1058 	if (vdd_max < 0)
1059 		return 0;
1060 
1061 	/* Prefer low bits for the boundary vdd_min values. */
1062 	vdd_min = mmc_vdd_to_ocrbitnum(vdd_min, true);
1063 	if (vdd_min < 0)
1064 		return 0;
1065 
1066 	/* Fill the mask, from max bit to min bit. */
1067 	while (vdd_max >= vdd_min)
1068 		mask |= 1 << vdd_max--;
1069 
1070 	return mask;
1071 }
1072 
1073 static int mmc_of_get_func_num(struct device_node *node)
1074 {
1075 	u32 reg;
1076 	int ret;
1077 
1078 	ret = of_property_read_u32(node, "reg", &reg);
1079 	if (ret < 0)
1080 		return ret;
1081 
1082 	return reg;
1083 }
1084 
1085 struct device_node *mmc_of_find_child_device(struct mmc_host *host,
1086 		unsigned func_num)
1087 {
1088 	struct device_node *node;
1089 
1090 	if (!host->parent || !host->parent->of_node)
1091 		return NULL;
1092 
1093 	for_each_child_of_node(host->parent->of_node, node) {
1094 		if (mmc_of_get_func_num(node) == func_num)
1095 			return node;
1096 	}
1097 
1098 	return NULL;
1099 }
1100 
1101 /*
1102  * Mask off any voltages we don't support and select
1103  * the lowest voltage
1104  */
1105 u32 mmc_select_voltage(struct mmc_host *host, u32 ocr)
1106 {
1107 	int bit;
1108 
1109 	/*
1110 	 * Sanity check the voltages that the card claims to
1111 	 * support.
1112 	 */
1113 	if (ocr & 0x7F) {
1114 		dev_warn(mmc_dev(host),
1115 		"card claims to support voltages below defined range\n");
1116 		ocr &= ~0x7F;
1117 	}
1118 
1119 	ocr &= host->ocr_avail;
1120 	if (!ocr) {
1121 		dev_warn(mmc_dev(host), "no support for card's volts\n");
1122 		return 0;
1123 	}
1124 
1125 	if (host->caps2 & MMC_CAP2_FULL_PWR_CYCLE) {
1126 		bit = ffs(ocr) - 1;
1127 		ocr &= 3 << bit;
1128 		mmc_power_cycle(host, ocr);
1129 	} else {
1130 		bit = fls(ocr) - 1;
1131 		ocr &= 3 << bit;
1132 		if (bit != host->ios.vdd)
1133 			dev_warn(mmc_dev(host), "exceeding card's volts\n");
1134 	}
1135 
1136 	return ocr;
1137 }
1138 
1139 int mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage)
1140 {
1141 	int err = 0;
1142 	int old_signal_voltage = host->ios.signal_voltage;
1143 
1144 	host->ios.signal_voltage = signal_voltage;
1145 	if (host->ops->start_signal_voltage_switch)
1146 		err = host->ops->start_signal_voltage_switch(host, &host->ios);
1147 
1148 	if (err)
1149 		host->ios.signal_voltage = old_signal_voltage;
1150 
1151 	return err;
1152 
1153 }
1154 
1155 void mmc_set_initial_signal_voltage(struct mmc_host *host)
1156 {
1157 	/* Try to set signal voltage to 3.3V but fall back to 1.8v or 1.2v */
1158 	if (!mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330))
1159 		dev_dbg(mmc_dev(host), "Initial signal voltage of 3.3v\n");
1160 	else if (!mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180))
1161 		dev_dbg(mmc_dev(host), "Initial signal voltage of 1.8v\n");
1162 	else if (!mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120))
1163 		dev_dbg(mmc_dev(host), "Initial signal voltage of 1.2v\n");
1164 }
1165 
1166 int mmc_host_set_uhs_voltage(struct mmc_host *host)
1167 {
1168 	u32 clock;
1169 
1170 	/*
1171 	 * During a signal voltage level switch, the clock must be gated
1172 	 * for 5 ms according to the SD spec
1173 	 */
1174 	clock = host->ios.clock;
1175 	host->ios.clock = 0;
1176 	mmc_set_ios(host);
1177 
1178 	if (mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180))
1179 		return -EAGAIN;
1180 
1181 	/* Keep clock gated for at least 10 ms, though spec only says 5 ms */
1182 	mmc_delay(10);
1183 	host->ios.clock = clock;
1184 	mmc_set_ios(host);
1185 
1186 	return 0;
1187 }
1188 
1189 int mmc_set_uhs_voltage(struct mmc_host *host, u32 ocr)
1190 {
1191 	struct mmc_command cmd = {};
1192 	int err = 0;
1193 
1194 	/*
1195 	 * If we cannot switch voltages, return failure so the caller
1196 	 * can continue without UHS mode
1197 	 */
1198 	if (!host->ops->start_signal_voltage_switch)
1199 		return -EPERM;
1200 	if (!host->ops->card_busy)
1201 		pr_warn("%s: cannot verify signal voltage switch\n",
1202 			mmc_hostname(host));
1203 
1204 	cmd.opcode = SD_SWITCH_VOLTAGE;
1205 	cmd.arg = 0;
1206 	cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
1207 
1208 	err = mmc_wait_for_cmd(host, &cmd, 0);
1209 	if (err)
1210 		goto power_cycle;
1211 
1212 	if (!mmc_host_is_spi(host) && (cmd.resp[0] & R1_ERROR))
1213 		return -EIO;
1214 
1215 	/*
1216 	 * The card should drive cmd and dat[0:3] low immediately
1217 	 * after the response of cmd11, but wait 1 ms to be sure
1218 	 */
1219 	mmc_delay(1);
1220 	if (host->ops->card_busy && !host->ops->card_busy(host)) {
1221 		err = -EAGAIN;
1222 		goto power_cycle;
1223 	}
1224 
1225 	if (mmc_host_set_uhs_voltage(host)) {
1226 		/*
1227 		 * Voltages may not have been switched, but we've already
1228 		 * sent CMD11, so a power cycle is required anyway
1229 		 */
1230 		err = -EAGAIN;
1231 		goto power_cycle;
1232 	}
1233 
1234 	/* Wait for at least 1 ms according to spec */
1235 	mmc_delay(1);
1236 
1237 	/*
1238 	 * Failure to switch is indicated by the card holding
1239 	 * dat[0:3] low
1240 	 */
1241 	if (host->ops->card_busy && host->ops->card_busy(host))
1242 		err = -EAGAIN;
1243 
1244 power_cycle:
1245 	if (err) {
1246 		pr_debug("%s: Signal voltage switch failed, "
1247 			"power cycling card\n", mmc_hostname(host));
1248 		mmc_power_cycle(host, ocr);
1249 	}
1250 
1251 	return err;
1252 }
1253 
1254 /*
1255  * Select timing parameters for host.
1256  */
1257 void mmc_set_timing(struct mmc_host *host, unsigned int timing)
1258 {
1259 	host->ios.timing = timing;
1260 	mmc_set_ios(host);
1261 }
1262 
1263 /*
1264  * Select appropriate driver type for host.
1265  */
1266 void mmc_set_driver_type(struct mmc_host *host, unsigned int drv_type)
1267 {
1268 	host->ios.drv_type = drv_type;
1269 	mmc_set_ios(host);
1270 }
1271 
1272 int mmc_select_drive_strength(struct mmc_card *card, unsigned int max_dtr,
1273 			      int card_drv_type, int *drv_type)
1274 {
1275 	struct mmc_host *host = card->host;
1276 	int host_drv_type = SD_DRIVER_TYPE_B;
1277 
1278 	*drv_type = 0;
1279 
1280 	if (!host->ops->select_drive_strength)
1281 		return 0;
1282 
1283 	/* Use SD definition of driver strength for hosts */
1284 	if (host->caps & MMC_CAP_DRIVER_TYPE_A)
1285 		host_drv_type |= SD_DRIVER_TYPE_A;
1286 
1287 	if (host->caps & MMC_CAP_DRIVER_TYPE_C)
1288 		host_drv_type |= SD_DRIVER_TYPE_C;
1289 
1290 	if (host->caps & MMC_CAP_DRIVER_TYPE_D)
1291 		host_drv_type |= SD_DRIVER_TYPE_D;
1292 
1293 	/*
1294 	 * The drive strength that the hardware can support
1295 	 * depends on the board design.  Pass the appropriate
1296 	 * information and let the hardware specific code
1297 	 * return what is possible given the options
1298 	 */
1299 	return host->ops->select_drive_strength(card, max_dtr,
1300 						host_drv_type,
1301 						card_drv_type,
1302 						drv_type);
1303 }
1304 
1305 /*
1306  * Apply power to the MMC stack.  This is a two-stage process.
1307  * First, we enable power to the card without the clock running.
1308  * We then wait a bit for the power to stabilise.  Finally,
1309  * enable the bus drivers and clock to the card.
1310  *
1311  * We must _NOT_ enable the clock prior to power stablising.
1312  *
1313  * If a host does all the power sequencing itself, ignore the
1314  * initial MMC_POWER_UP stage.
1315  */
1316 void mmc_power_up(struct mmc_host *host, u32 ocr)
1317 {
1318 	if (host->ios.power_mode == MMC_POWER_ON)
1319 		return;
1320 
1321 	mmc_pwrseq_pre_power_on(host);
1322 
1323 	host->ios.vdd = fls(ocr) - 1;
1324 	host->ios.power_mode = MMC_POWER_UP;
1325 	/* Set initial state and call mmc_set_ios */
1326 	mmc_set_initial_state(host);
1327 
1328 	mmc_set_initial_signal_voltage(host);
1329 
1330 	/*
1331 	 * This delay should be sufficient to allow the power supply
1332 	 * to reach the minimum voltage.
1333 	 */
1334 	mmc_delay(host->ios.power_delay_ms);
1335 
1336 	mmc_pwrseq_post_power_on(host);
1337 
1338 	host->ios.clock = host->f_init;
1339 
1340 	host->ios.power_mode = MMC_POWER_ON;
1341 	mmc_set_ios(host);
1342 
1343 	/*
1344 	 * This delay must be at least 74 clock sizes, or 1 ms, or the
1345 	 * time required to reach a stable voltage.
1346 	 */
1347 	mmc_delay(host->ios.power_delay_ms);
1348 }
1349 
1350 void mmc_power_off(struct mmc_host *host)
1351 {
1352 	if (host->ios.power_mode == MMC_POWER_OFF)
1353 		return;
1354 
1355 	mmc_pwrseq_power_off(host);
1356 
1357 	host->ios.clock = 0;
1358 	host->ios.vdd = 0;
1359 
1360 	host->ios.power_mode = MMC_POWER_OFF;
1361 	/* Set initial state and call mmc_set_ios */
1362 	mmc_set_initial_state(host);
1363 
1364 	/*
1365 	 * Some configurations, such as the 802.11 SDIO card in the OLPC
1366 	 * XO-1.5, require a short delay after poweroff before the card
1367 	 * can be successfully turned on again.
1368 	 */
1369 	mmc_delay(1);
1370 }
1371 
1372 void mmc_power_cycle(struct mmc_host *host, u32 ocr)
1373 {
1374 	mmc_power_off(host);
1375 	/* Wait at least 1 ms according to SD spec */
1376 	mmc_delay(1);
1377 	mmc_power_up(host, ocr);
1378 }
1379 
1380 /*
1381  * Assign a mmc bus handler to a host. Only one bus handler may control a
1382  * host at any given time.
1383  */
1384 void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops)
1385 {
1386 	host->bus_ops = ops;
1387 }
1388 
1389 /*
1390  * Remove the current bus handler from a host.
1391  */
1392 void mmc_detach_bus(struct mmc_host *host)
1393 {
1394 	host->bus_ops = NULL;
1395 }
1396 
1397 void _mmc_detect_change(struct mmc_host *host, unsigned long delay, bool cd_irq)
1398 {
1399 	/*
1400 	 * Prevent system sleep for 5s to allow user space to consume the
1401 	 * corresponding uevent. This is especially useful, when CD irq is used
1402 	 * as a system wakeup, but doesn't hurt in other cases.
1403 	 */
1404 	if (cd_irq && !(host->caps & MMC_CAP_NEEDS_POLL))
1405 		__pm_wakeup_event(host->ws, 5000);
1406 
1407 	host->detect_change = 1;
1408 	mmc_schedule_delayed_work(&host->detect, delay);
1409 }
1410 
1411 /**
1412  *	mmc_detect_change - process change of state on a MMC socket
1413  *	@host: host which changed state.
1414  *	@delay: optional delay to wait before detection (jiffies)
1415  *
1416  *	MMC drivers should call this when they detect a card has been
1417  *	inserted or removed. The MMC layer will confirm that any
1418  *	present card is still functional, and initialize any newly
1419  *	inserted.
1420  */
1421 void mmc_detect_change(struct mmc_host *host, unsigned long delay)
1422 {
1423 	_mmc_detect_change(host, delay, true);
1424 }
1425 EXPORT_SYMBOL(mmc_detect_change);
1426 
1427 void mmc_init_erase(struct mmc_card *card)
1428 {
1429 	unsigned int sz;
1430 
1431 	if (is_power_of_2(card->erase_size))
1432 		card->erase_shift = ffs(card->erase_size) - 1;
1433 	else
1434 		card->erase_shift = 0;
1435 
1436 	/*
1437 	 * It is possible to erase an arbitrarily large area of an SD or MMC
1438 	 * card.  That is not desirable because it can take a long time
1439 	 * (minutes) potentially delaying more important I/O, and also the
1440 	 * timeout calculations become increasingly hugely over-estimated.
1441 	 * Consequently, 'pref_erase' is defined as a guide to limit erases
1442 	 * to that size and alignment.
1443 	 *
1444 	 * For SD cards that define Allocation Unit size, limit erases to one
1445 	 * Allocation Unit at a time.
1446 	 * For MMC, have a stab at ai good value and for modern cards it will
1447 	 * end up being 4MiB. Note that if the value is too small, it can end
1448 	 * up taking longer to erase. Also note, erase_size is already set to
1449 	 * High Capacity Erase Size if available when this function is called.
1450 	 */
1451 	if (mmc_card_sd(card) && card->ssr.au) {
1452 		card->pref_erase = card->ssr.au;
1453 		card->erase_shift = ffs(card->ssr.au) - 1;
1454 	} else if (card->erase_size) {
1455 		sz = (card->csd.capacity << (card->csd.read_blkbits - 9)) >> 11;
1456 		if (sz < 128)
1457 			card->pref_erase = 512 * 1024 / 512;
1458 		else if (sz < 512)
1459 			card->pref_erase = 1024 * 1024 / 512;
1460 		else if (sz < 1024)
1461 			card->pref_erase = 2 * 1024 * 1024 / 512;
1462 		else
1463 			card->pref_erase = 4 * 1024 * 1024 / 512;
1464 		if (card->pref_erase < card->erase_size)
1465 			card->pref_erase = card->erase_size;
1466 		else {
1467 			sz = card->pref_erase % card->erase_size;
1468 			if (sz)
1469 				card->pref_erase += card->erase_size - sz;
1470 		}
1471 	} else
1472 		card->pref_erase = 0;
1473 }
1474 
1475 static unsigned int mmc_mmc_erase_timeout(struct mmc_card *card,
1476 				          unsigned int arg, unsigned int qty)
1477 {
1478 	unsigned int erase_timeout;
1479 
1480 	if (arg == MMC_DISCARD_ARG ||
1481 	    (arg == MMC_TRIM_ARG && card->ext_csd.rev >= 6)) {
1482 		erase_timeout = card->ext_csd.trim_timeout;
1483 	} else if (card->ext_csd.erase_group_def & 1) {
1484 		/* High Capacity Erase Group Size uses HC timeouts */
1485 		if (arg == MMC_TRIM_ARG)
1486 			erase_timeout = card->ext_csd.trim_timeout;
1487 		else
1488 			erase_timeout = card->ext_csd.hc_erase_timeout;
1489 	} else {
1490 		/* CSD Erase Group Size uses write timeout */
1491 		unsigned int mult = (10 << card->csd.r2w_factor);
1492 		unsigned int timeout_clks = card->csd.taac_clks * mult;
1493 		unsigned int timeout_us;
1494 
1495 		/* Avoid overflow: e.g. taac_ns=80000000 mult=1280 */
1496 		if (card->csd.taac_ns < 1000000)
1497 			timeout_us = (card->csd.taac_ns * mult) / 1000;
1498 		else
1499 			timeout_us = (card->csd.taac_ns / 1000) * mult;
1500 
1501 		/*
1502 		 * ios.clock is only a target.  The real clock rate might be
1503 		 * less but not that much less, so fudge it by multiplying by 2.
1504 		 */
1505 		timeout_clks <<= 1;
1506 		timeout_us += (timeout_clks * 1000) /
1507 			      (card->host->ios.clock / 1000);
1508 
1509 		erase_timeout = timeout_us / 1000;
1510 
1511 		/*
1512 		 * Theoretically, the calculation could underflow so round up
1513 		 * to 1ms in that case.
1514 		 */
1515 		if (!erase_timeout)
1516 			erase_timeout = 1;
1517 	}
1518 
1519 	/* Multiplier for secure operations */
1520 	if (arg & MMC_SECURE_ARGS) {
1521 		if (arg == MMC_SECURE_ERASE_ARG)
1522 			erase_timeout *= card->ext_csd.sec_erase_mult;
1523 		else
1524 			erase_timeout *= card->ext_csd.sec_trim_mult;
1525 	}
1526 
1527 	erase_timeout *= qty;
1528 
1529 	/*
1530 	 * Ensure at least a 1 second timeout for SPI as per
1531 	 * 'mmc_set_data_timeout()'
1532 	 */
1533 	if (mmc_host_is_spi(card->host) && erase_timeout < 1000)
1534 		erase_timeout = 1000;
1535 
1536 	return erase_timeout;
1537 }
1538 
1539 static unsigned int mmc_sd_erase_timeout(struct mmc_card *card,
1540 					 unsigned int arg,
1541 					 unsigned int qty)
1542 {
1543 	unsigned int erase_timeout;
1544 
1545 	/* for DISCARD none of the below calculation applies.
1546 	 * the busy timeout is 250msec per discard command.
1547 	 */
1548 	if (arg == SD_DISCARD_ARG)
1549 		return SD_DISCARD_TIMEOUT_MS;
1550 
1551 	if (card->ssr.erase_timeout) {
1552 		/* Erase timeout specified in SD Status Register (SSR) */
1553 		erase_timeout = card->ssr.erase_timeout * qty +
1554 				card->ssr.erase_offset;
1555 	} else {
1556 		/*
1557 		 * Erase timeout not specified in SD Status Register (SSR) so
1558 		 * use 250ms per write block.
1559 		 */
1560 		erase_timeout = 250 * qty;
1561 	}
1562 
1563 	/* Must not be less than 1 second */
1564 	if (erase_timeout < 1000)
1565 		erase_timeout = 1000;
1566 
1567 	return erase_timeout;
1568 }
1569 
1570 static unsigned int mmc_erase_timeout(struct mmc_card *card,
1571 				      unsigned int arg,
1572 				      unsigned int qty)
1573 {
1574 	if (mmc_card_sd(card))
1575 		return mmc_sd_erase_timeout(card, arg, qty);
1576 	else
1577 		return mmc_mmc_erase_timeout(card, arg, qty);
1578 }
1579 
1580 static int mmc_do_erase(struct mmc_card *card, unsigned int from,
1581 			unsigned int to, unsigned int arg)
1582 {
1583 	struct mmc_command cmd = {};
1584 	unsigned int qty = 0, busy_timeout = 0;
1585 	bool use_r1b_resp = false;
1586 	int err;
1587 
1588 	mmc_retune_hold(card->host);
1589 
1590 	/*
1591 	 * qty is used to calculate the erase timeout which depends on how many
1592 	 * erase groups (or allocation units in SD terminology) are affected.
1593 	 * We count erasing part of an erase group as one erase group.
1594 	 * For SD, the allocation units are always a power of 2.  For MMC, the
1595 	 * erase group size is almost certainly also power of 2, but it does not
1596 	 * seem to insist on that in the JEDEC standard, so we fall back to
1597 	 * division in that case.  SD may not specify an allocation unit size,
1598 	 * in which case the timeout is based on the number of write blocks.
1599 	 *
1600 	 * Note that the timeout for secure trim 2 will only be correct if the
1601 	 * number of erase groups specified is the same as the total of all
1602 	 * preceding secure trim 1 commands.  Since the power may have been
1603 	 * lost since the secure trim 1 commands occurred, it is generally
1604 	 * impossible to calculate the secure trim 2 timeout correctly.
1605 	 */
1606 	if (card->erase_shift)
1607 		qty += ((to >> card->erase_shift) -
1608 			(from >> card->erase_shift)) + 1;
1609 	else if (mmc_card_sd(card))
1610 		qty += to - from + 1;
1611 	else
1612 		qty += ((to / card->erase_size) -
1613 			(from / card->erase_size)) + 1;
1614 
1615 	if (!mmc_card_blockaddr(card)) {
1616 		from <<= 9;
1617 		to <<= 9;
1618 	}
1619 
1620 	if (mmc_card_sd(card))
1621 		cmd.opcode = SD_ERASE_WR_BLK_START;
1622 	else
1623 		cmd.opcode = MMC_ERASE_GROUP_START;
1624 	cmd.arg = from;
1625 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
1626 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
1627 	if (err) {
1628 		pr_err("mmc_erase: group start error %d, "
1629 		       "status %#x\n", err, cmd.resp[0]);
1630 		err = -EIO;
1631 		goto out;
1632 	}
1633 
1634 	memset(&cmd, 0, sizeof(struct mmc_command));
1635 	if (mmc_card_sd(card))
1636 		cmd.opcode = SD_ERASE_WR_BLK_END;
1637 	else
1638 		cmd.opcode = MMC_ERASE_GROUP_END;
1639 	cmd.arg = to;
1640 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
1641 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
1642 	if (err) {
1643 		pr_err("mmc_erase: group end error %d, status %#x\n",
1644 		       err, cmd.resp[0]);
1645 		err = -EIO;
1646 		goto out;
1647 	}
1648 
1649 	memset(&cmd, 0, sizeof(struct mmc_command));
1650 	cmd.opcode = MMC_ERASE;
1651 	cmd.arg = arg;
1652 	busy_timeout = mmc_erase_timeout(card, arg, qty);
1653 	/*
1654 	 * If the host controller supports busy signalling and the timeout for
1655 	 * the erase operation does not exceed the max_busy_timeout, we should
1656 	 * use R1B response. Or we need to prevent the host from doing hw busy
1657 	 * detection, which is done by converting to a R1 response instead.
1658 	 * Note, some hosts requires R1B, which also means they are on their own
1659 	 * when it comes to deal with the busy timeout.
1660 	 */
1661 	if (!(card->host->caps & MMC_CAP_NEED_RSP_BUSY) &&
1662 	    card->host->max_busy_timeout &&
1663 	    busy_timeout > card->host->max_busy_timeout) {
1664 		cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
1665 	} else {
1666 		cmd.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
1667 		cmd.busy_timeout = busy_timeout;
1668 		use_r1b_resp = true;
1669 	}
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, 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) && (arg & MMC_TRIM_ARGS) &&
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_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->hw_reset)
2004 		return;
2005 	host->ops->hw_reset(host);
2006 }
2007 
2008 /**
2009  * mmc_hw_reset - reset the card in hardware
2010  * @host: MMC host to which the card is attached
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_host *host)
2019 {
2020 	int ret;
2021 
2022 	ret = host->bus_ops->hw_reset(host);
2023 	if (ret < 0)
2024 		pr_warn("%s: tried to HW reset card, got error %d\n",
2025 			mmc_hostname(host), ret);
2026 
2027 	return ret;
2028 }
2029 EXPORT_SYMBOL(mmc_hw_reset);
2030 
2031 int mmc_sw_reset(struct mmc_host *host)
2032 {
2033 	int ret;
2034 
2035 	if (!host->bus_ops->sw_reset)
2036 		return -EOPNOTSUPP;
2037 
2038 	ret = host->bus_ops->sw_reset(host);
2039 	if (ret)
2040 		pr_warn("%s: tried to SW reset card, got error %d\n",
2041 			mmc_hostname(host), ret);
2042 
2043 	return ret;
2044 }
2045 EXPORT_SYMBOL(mmc_sw_reset);
2046 
2047 static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
2048 {
2049 	host->f_init = freq;
2050 
2051 	pr_debug("%s: %s: trying to init card at %u Hz\n",
2052 		mmc_hostname(host), __func__, host->f_init);
2053 
2054 	mmc_power_up(host, host->ocr_avail);
2055 
2056 	/*
2057 	 * Some eMMCs (with VCCQ always on) may not be reset after power up, so
2058 	 * do a hardware reset if possible.
2059 	 */
2060 	mmc_hw_reset_for_init(host);
2061 
2062 	/*
2063 	 * sdio_reset sends CMD52 to reset card.  Since we do not know
2064 	 * if the card is being re-initialized, just send it.  CMD52
2065 	 * should be ignored by SD/eMMC cards.
2066 	 * Skip it if we already know that we do not support SDIO commands
2067 	 */
2068 	if (!(host->caps2 & MMC_CAP2_NO_SDIO))
2069 		sdio_reset(host);
2070 
2071 	mmc_go_idle(host);
2072 
2073 	if (!(host->caps2 & MMC_CAP2_NO_SD)) {
2074 		if (mmc_send_if_cond_pcie(host, host->ocr_avail))
2075 			goto out;
2076 		if (mmc_card_sd_express(host))
2077 			return 0;
2078 	}
2079 
2080 	/* Order's important: probe SDIO, then SD, then MMC */
2081 	if (!(host->caps2 & MMC_CAP2_NO_SDIO))
2082 		if (!mmc_attach_sdio(host))
2083 			return 0;
2084 
2085 	if (!(host->caps2 & MMC_CAP2_NO_SD))
2086 		if (!mmc_attach_sd(host))
2087 			return 0;
2088 
2089 	if (!(host->caps2 & MMC_CAP2_NO_MMC))
2090 		if (!mmc_attach_mmc(host))
2091 			return 0;
2092 
2093 out:
2094 	mmc_power_off(host);
2095 	return -EIO;
2096 }
2097 
2098 int _mmc_detect_card_removed(struct mmc_host *host)
2099 {
2100 	int ret;
2101 
2102 	if (!host->card || mmc_card_removed(host->card))
2103 		return 1;
2104 
2105 	ret = host->bus_ops->alive(host);
2106 
2107 	/*
2108 	 * Card detect status and alive check may be out of sync if card is
2109 	 * removed slowly, when card detect switch changes while card/slot
2110 	 * pads are still contacted in hardware (refer to "SD Card Mechanical
2111 	 * Addendum, Appendix C: Card Detection Switch"). So reschedule a
2112 	 * detect work 200ms later for this case.
2113 	 */
2114 	if (!ret && host->ops->get_cd && !host->ops->get_cd(host)) {
2115 		mmc_detect_change(host, msecs_to_jiffies(200));
2116 		pr_debug("%s: card removed too slowly\n", mmc_hostname(host));
2117 	}
2118 
2119 	if (ret) {
2120 		mmc_card_set_removed(host->card);
2121 		pr_debug("%s: card remove detected\n", mmc_hostname(host));
2122 	}
2123 
2124 	return ret;
2125 }
2126 
2127 int mmc_detect_card_removed(struct mmc_host *host)
2128 {
2129 	struct mmc_card *card = host->card;
2130 	int ret;
2131 
2132 	WARN_ON(!host->claimed);
2133 
2134 	if (!card)
2135 		return 1;
2136 
2137 	if (!mmc_card_is_removable(host))
2138 		return 0;
2139 
2140 	ret = mmc_card_removed(card);
2141 	/*
2142 	 * The card will be considered unchanged unless we have been asked to
2143 	 * detect a change or host requires polling to provide card detection.
2144 	 */
2145 	if (!host->detect_change && !(host->caps & MMC_CAP_NEEDS_POLL))
2146 		return ret;
2147 
2148 	host->detect_change = 0;
2149 	if (!ret) {
2150 		ret = _mmc_detect_card_removed(host);
2151 		if (ret && (host->caps & MMC_CAP_NEEDS_POLL)) {
2152 			/*
2153 			 * Schedule a detect work as soon as possible to let a
2154 			 * rescan handle the card removal.
2155 			 */
2156 			cancel_delayed_work(&host->detect);
2157 			_mmc_detect_change(host, 0, false);
2158 		}
2159 	}
2160 
2161 	return ret;
2162 }
2163 EXPORT_SYMBOL(mmc_detect_card_removed);
2164 
2165 void mmc_rescan(struct work_struct *work)
2166 {
2167 	struct mmc_host *host =
2168 		container_of(work, struct mmc_host, detect.work);
2169 	int i;
2170 
2171 	if (host->rescan_disable)
2172 		return;
2173 
2174 	/* If there is a non-removable card registered, only scan once */
2175 	if (!mmc_card_is_removable(host) && host->rescan_entered)
2176 		return;
2177 	host->rescan_entered = 1;
2178 
2179 	if (host->trigger_card_event && host->ops->card_event) {
2180 		mmc_claim_host(host);
2181 		host->ops->card_event(host);
2182 		mmc_release_host(host);
2183 		host->trigger_card_event = false;
2184 	}
2185 
2186 	/* Verify a registered card to be functional, else remove it. */
2187 	if (host->bus_ops)
2188 		host->bus_ops->detect(host);
2189 
2190 	host->detect_change = 0;
2191 
2192 	/* if there still is a card present, stop here */
2193 	if (host->bus_ops != NULL)
2194 		goto out;
2195 
2196 	mmc_claim_host(host);
2197 	if (mmc_card_is_removable(host) && host->ops->get_cd &&
2198 			host->ops->get_cd(host) == 0) {
2199 		mmc_power_off(host);
2200 		mmc_release_host(host);
2201 		goto out;
2202 	}
2203 
2204 	/* If an SD express card is present, then leave it as is. */
2205 	if (mmc_card_sd_express(host)) {
2206 		mmc_release_host(host);
2207 		goto out;
2208 	}
2209 
2210 	for (i = 0; i < ARRAY_SIZE(freqs); i++) {
2211 		unsigned int freq = freqs[i];
2212 		if (freq > host->f_max) {
2213 			if (i + 1 < ARRAY_SIZE(freqs))
2214 				continue;
2215 			freq = host->f_max;
2216 		}
2217 		if (!mmc_rescan_try_freq(host, max(freq, host->f_min)))
2218 			break;
2219 		if (freqs[i] <= host->f_min)
2220 			break;
2221 	}
2222 	mmc_release_host(host);
2223 
2224  out:
2225 	if (host->caps & MMC_CAP_NEEDS_POLL)
2226 		mmc_schedule_delayed_work(&host->detect, HZ);
2227 }
2228 
2229 void mmc_start_host(struct mmc_host *host)
2230 {
2231 	host->f_init = max(min(freqs[0], host->f_max), host->f_min);
2232 	host->rescan_disable = 0;
2233 
2234 	if (!(host->caps2 & MMC_CAP2_NO_PRESCAN_POWERUP)) {
2235 		mmc_claim_host(host);
2236 		mmc_power_up(host, host->ocr_avail);
2237 		mmc_release_host(host);
2238 	}
2239 
2240 	mmc_gpiod_request_cd_irq(host);
2241 	_mmc_detect_change(host, 0, false);
2242 }
2243 
2244 void mmc_stop_host(struct mmc_host *host)
2245 {
2246 	if (host->slot.cd_irq >= 0) {
2247 		mmc_gpio_set_cd_wake(host, false);
2248 		disable_irq(host->slot.cd_irq);
2249 	}
2250 
2251 	host->rescan_disable = 1;
2252 	cancel_delayed_work_sync(&host->detect);
2253 
2254 	/* clear pm flags now and let card drivers set them as needed */
2255 	host->pm_flags = 0;
2256 
2257 	if (host->bus_ops) {
2258 		/* Calling bus_ops->remove() with a claimed host can deadlock */
2259 		host->bus_ops->remove(host);
2260 		mmc_claim_host(host);
2261 		mmc_detach_bus(host);
2262 		mmc_power_off(host);
2263 		mmc_release_host(host);
2264 		return;
2265 	}
2266 
2267 	mmc_claim_host(host);
2268 	mmc_power_off(host);
2269 	mmc_release_host(host);
2270 }
2271 
2272 static int __init mmc_init(void)
2273 {
2274 	int ret;
2275 
2276 	ret = mmc_register_bus();
2277 	if (ret)
2278 		return ret;
2279 
2280 	ret = mmc_register_host_class();
2281 	if (ret)
2282 		goto unregister_bus;
2283 
2284 	ret = sdio_register_bus();
2285 	if (ret)
2286 		goto unregister_host_class;
2287 
2288 	return 0;
2289 
2290 unregister_host_class:
2291 	mmc_unregister_host_class();
2292 unregister_bus:
2293 	mmc_unregister_bus();
2294 	return ret;
2295 }
2296 
2297 static void __exit mmc_exit(void)
2298 {
2299 	sdio_unregister_bus();
2300 	mmc_unregister_host_class();
2301 	mmc_unregister_bus();
2302 }
2303 
2304 subsys_initcall(mmc_init);
2305 module_exit(mmc_exit);
2306 
2307 MODULE_LICENSE("GPL");
2308