xref: /openbmc/linux/drivers/mmc/core/core.c (revision 3ce311af)
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 "bus.h"
41 #include "host.h"
42 #include "sdio_bus.h"
43 #include "pwrseq.h"
44 
45 #include "mmc_ops.h"
46 #include "sd_ops.h"
47 #include "sdio_ops.h"
48 
49 /* The max erase timeout, used when host->max_busy_timeout isn't specified */
50 #define MMC_ERASE_TIMEOUT_MS	(60 * 1000) /* 60 s */
51 #define SD_DISCARD_TIMEOUT_MS	(250)
52 
53 static const unsigned freqs[] = { 400000, 300000, 200000, 100000 };
54 
55 /*
56  * Enabling software CRCs on the data blocks can be a significant (30%)
57  * performance cost, and for other reasons may not always be desired.
58  * So we allow it it to be disabled.
59  */
60 bool use_spi_crc = 1;
61 module_param(use_spi_crc, bool, 0);
62 
63 static int mmc_schedule_delayed_work(struct delayed_work *work,
64 				     unsigned long delay)
65 {
66 	/*
67 	 * We use the system_freezable_wq, because of two reasons.
68 	 * First, it allows several works (not the same work item) to be
69 	 * executed simultaneously. Second, the queue becomes frozen when
70 	 * userspace becomes frozen during system PM.
71 	 */
72 	return queue_delayed_work(system_freezable_wq, work, delay);
73 }
74 
75 #ifdef CONFIG_FAIL_MMC_REQUEST
76 
77 /*
78  * Internal function. Inject random data errors.
79  * If mmc_data is NULL no errors are injected.
80  */
81 static void mmc_should_fail_request(struct mmc_host *host,
82 				    struct mmc_request *mrq)
83 {
84 	struct mmc_command *cmd = mrq->cmd;
85 	struct mmc_data *data = mrq->data;
86 	static const int data_errors[] = {
87 		-ETIMEDOUT,
88 		-EILSEQ,
89 		-EIO,
90 	};
91 
92 	if (!data)
93 		return;
94 
95 	if ((cmd && cmd->error) || data->error ||
96 	    !should_fail(&host->fail_mmc_request, data->blksz * data->blocks))
97 		return;
98 
99 	data->error = data_errors[prandom_u32() % ARRAY_SIZE(data_errors)];
100 	data->bytes_xfered = (prandom_u32() % (data->bytes_xfered >> 9)) << 9;
101 }
102 
103 #else /* CONFIG_FAIL_MMC_REQUEST */
104 
105 static inline void mmc_should_fail_request(struct mmc_host *host,
106 					   struct mmc_request *mrq)
107 {
108 }
109 
110 #endif /* CONFIG_FAIL_MMC_REQUEST */
111 
112 static inline void mmc_complete_cmd(struct mmc_request *mrq)
113 {
114 	if (mrq->cap_cmd_during_tfr && !completion_done(&mrq->cmd_completion))
115 		complete_all(&mrq->cmd_completion);
116 }
117 
118 void mmc_command_done(struct mmc_host *host, struct mmc_request *mrq)
119 {
120 	if (!mrq->cap_cmd_during_tfr)
121 		return;
122 
123 	mmc_complete_cmd(mrq);
124 
125 	pr_debug("%s: cmd done, tfr ongoing (CMD%u)\n",
126 		 mmc_hostname(host), mrq->cmd->opcode);
127 }
128 EXPORT_SYMBOL(mmc_command_done);
129 
130 /**
131  *	mmc_request_done - finish processing an MMC request
132  *	@host: MMC host which completed request
133  *	@mrq: MMC request which request
134  *
135  *	MMC drivers should call this function when they have completed
136  *	their processing of a request.
137  */
138 void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
139 {
140 	struct mmc_command *cmd = mrq->cmd;
141 	int err = cmd->error;
142 
143 	/* Flag re-tuning needed on CRC errors */
144 	if (cmd->opcode != MMC_SEND_TUNING_BLOCK &&
145 	    cmd->opcode != MMC_SEND_TUNING_BLOCK_HS200 &&
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 		/*
407 		 * If host has timed out waiting for the sanitize
408 		 * to complete, card might be still in programming state
409 		 * so let's try to bring the card out of programming
410 		 * state.
411 		 */
412 		if (cmd->sanitize_busy && cmd->error == -ETIMEDOUT) {
413 			if (!mmc_interrupt_hpi(host->card)) {
414 				pr_warn("%s: %s: Interrupted sanitize\n",
415 					mmc_hostname(host), __func__);
416 				cmd->error = 0;
417 				break;
418 			} else {
419 				pr_err("%s: %s: Failed to interrupt sanitize\n",
420 				       mmc_hostname(host), __func__);
421 			}
422 		}
423 		if (!cmd->error || !cmd->retries ||
424 		    mmc_card_removed(host->card))
425 			break;
426 
427 		mmc_retune_recheck(host);
428 
429 		pr_debug("%s: req failed (CMD%u): %d, retrying...\n",
430 			 mmc_hostname(host), cmd->opcode, cmd->error);
431 		cmd->retries--;
432 		cmd->error = 0;
433 		__mmc_start_request(host, mrq);
434 	}
435 
436 	mmc_retune_release(host);
437 }
438 EXPORT_SYMBOL(mmc_wait_for_req_done);
439 
440 /*
441  * mmc_cqe_start_req - Start a CQE request.
442  * @host: MMC host to start the request
443  * @mrq: request to start
444  *
445  * Start the request, re-tuning if needed and it is possible. Returns an error
446  * code if the request fails to start or -EBUSY if CQE is busy.
447  */
448 int mmc_cqe_start_req(struct mmc_host *host, struct mmc_request *mrq)
449 {
450 	int err;
451 
452 	/*
453 	 * CQE cannot process re-tuning commands. Caller must hold retuning
454 	 * while CQE is in use.  Re-tuning can happen here only when CQE has no
455 	 * active requests i.e. this is the first.  Note, re-tuning will call
456 	 * ->cqe_off().
457 	 */
458 	err = mmc_retune(host);
459 	if (err)
460 		goto out_err;
461 
462 	mrq->host = host;
463 
464 	mmc_mrq_pr_debug(host, mrq, true);
465 
466 	err = mmc_mrq_prep(host, mrq);
467 	if (err)
468 		goto out_err;
469 
470 	err = host->cqe_ops->cqe_request(host, mrq);
471 	if (err)
472 		goto out_err;
473 
474 	trace_mmc_request_start(host, mrq);
475 
476 	return 0;
477 
478 out_err:
479 	if (mrq->cmd) {
480 		pr_debug("%s: failed to start CQE direct CMD%u, error %d\n",
481 			 mmc_hostname(host), mrq->cmd->opcode, err);
482 	} else {
483 		pr_debug("%s: failed to start CQE transfer for tag %d, error %d\n",
484 			 mmc_hostname(host), mrq->tag, err);
485 	}
486 	return err;
487 }
488 EXPORT_SYMBOL(mmc_cqe_start_req);
489 
490 /**
491  *	mmc_cqe_request_done - CQE has finished processing an MMC request
492  *	@host: MMC host which completed request
493  *	@mrq: MMC request which completed
494  *
495  *	CQE drivers should call this function when they have completed
496  *	their processing of a request.
497  */
498 void mmc_cqe_request_done(struct mmc_host *host, struct mmc_request *mrq)
499 {
500 	mmc_should_fail_request(host, mrq);
501 
502 	/* Flag re-tuning needed on CRC errors */
503 	if ((mrq->cmd && mrq->cmd->error == -EILSEQ) ||
504 	    (mrq->data && mrq->data->error == -EILSEQ))
505 		mmc_retune_needed(host);
506 
507 	trace_mmc_request_done(host, mrq);
508 
509 	if (mrq->cmd) {
510 		pr_debug("%s: CQE req done (direct CMD%u): %d\n",
511 			 mmc_hostname(host), mrq->cmd->opcode, mrq->cmd->error);
512 	} else {
513 		pr_debug("%s: CQE transfer done tag %d\n",
514 			 mmc_hostname(host), mrq->tag);
515 	}
516 
517 	if (mrq->data) {
518 		pr_debug("%s:     %d bytes transferred: %d\n",
519 			 mmc_hostname(host),
520 			 mrq->data->bytes_xfered, mrq->data->error);
521 	}
522 
523 	mrq->done(mrq);
524 }
525 EXPORT_SYMBOL(mmc_cqe_request_done);
526 
527 /**
528  *	mmc_cqe_post_req - CQE post process of a completed MMC request
529  *	@host: MMC host
530  *	@mrq: MMC request to be processed
531  */
532 void mmc_cqe_post_req(struct mmc_host *host, struct mmc_request *mrq)
533 {
534 	if (host->cqe_ops->cqe_post_req)
535 		host->cqe_ops->cqe_post_req(host, mrq);
536 }
537 EXPORT_SYMBOL(mmc_cqe_post_req);
538 
539 /* Arbitrary 1 second timeout */
540 #define MMC_CQE_RECOVERY_TIMEOUT	1000
541 
542 /*
543  * mmc_cqe_recovery - Recover from CQE errors.
544  * @host: MMC host to recover
545  *
546  * Recovery consists of stopping CQE, stopping eMMC, discarding the queue in
547  * in eMMC, and discarding the queue in CQE. CQE must call
548  * mmc_cqe_request_done() on all requests. An error is returned if the eMMC
549  * fails to discard its queue.
550  */
551 int mmc_cqe_recovery(struct mmc_host *host)
552 {
553 	struct mmc_command cmd;
554 	int err;
555 
556 	mmc_retune_hold_now(host);
557 
558 	/*
559 	 * Recovery is expected seldom, if at all, but it reduces performance,
560 	 * so make sure it is not completely silent.
561 	 */
562 	pr_warn("%s: running CQE recovery\n", mmc_hostname(host));
563 
564 	host->cqe_ops->cqe_recovery_start(host);
565 
566 	memset(&cmd, 0, sizeof(cmd));
567 	cmd.opcode       = MMC_STOP_TRANSMISSION,
568 	cmd.flags        = MMC_RSP_R1B | MMC_CMD_AC,
569 	cmd.flags       &= ~MMC_RSP_CRC; /* Ignore CRC */
570 	cmd.busy_timeout = MMC_CQE_RECOVERY_TIMEOUT,
571 	mmc_wait_for_cmd(host, &cmd, 0);
572 
573 	memset(&cmd, 0, sizeof(cmd));
574 	cmd.opcode       = MMC_CMDQ_TASK_MGMT;
575 	cmd.arg          = 1; /* Discard entire queue */
576 	cmd.flags        = MMC_RSP_R1B | MMC_CMD_AC;
577 	cmd.flags       &= ~MMC_RSP_CRC; /* Ignore CRC */
578 	cmd.busy_timeout = MMC_CQE_RECOVERY_TIMEOUT,
579 	err = mmc_wait_for_cmd(host, &cmd, 0);
580 
581 	host->cqe_ops->cqe_recovery_finish(host);
582 
583 	mmc_retune_release(host);
584 
585 	return err;
586 }
587 EXPORT_SYMBOL(mmc_cqe_recovery);
588 
589 /**
590  *	mmc_is_req_done - Determine if a 'cap_cmd_during_tfr' request is done
591  *	@host: MMC host
592  *	@mrq: MMC request
593  *
594  *	mmc_is_req_done() is used with requests that have
595  *	mrq->cap_cmd_during_tfr = true. mmc_is_req_done() must be called after
596  *	starting a request and before waiting for it to complete. That is,
597  *	either in between calls to mmc_start_req(), or after mmc_wait_for_req()
598  *	and before mmc_wait_for_req_done(). If it is called at other times the
599  *	result is not meaningful.
600  */
601 bool mmc_is_req_done(struct mmc_host *host, struct mmc_request *mrq)
602 {
603 	return completion_done(&mrq->completion);
604 }
605 EXPORT_SYMBOL(mmc_is_req_done);
606 
607 /**
608  *	mmc_wait_for_req - start a request and wait for completion
609  *	@host: MMC host to start command
610  *	@mrq: MMC request to start
611  *
612  *	Start a new MMC custom command request for a host, and wait
613  *	for the command to complete. In the case of 'cap_cmd_during_tfr'
614  *	requests, the transfer is ongoing and the caller can issue further
615  *	commands that do not use the data lines, and then wait by calling
616  *	mmc_wait_for_req_done().
617  *	Does not attempt to parse the response.
618  */
619 void mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq)
620 {
621 	__mmc_start_req(host, mrq);
622 
623 	if (!mrq->cap_cmd_during_tfr)
624 		mmc_wait_for_req_done(host, mrq);
625 }
626 EXPORT_SYMBOL(mmc_wait_for_req);
627 
628 /**
629  *	mmc_wait_for_cmd - start a command and wait for completion
630  *	@host: MMC host to start command
631  *	@cmd: MMC command to start
632  *	@retries: maximum number of retries
633  *
634  *	Start a new MMC command for a host, and wait for the command
635  *	to complete.  Return any error that occurred while the command
636  *	was executing.  Do not attempt to parse the response.
637  */
638 int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries)
639 {
640 	struct mmc_request mrq = {};
641 
642 	WARN_ON(!host->claimed);
643 
644 	memset(cmd->resp, 0, sizeof(cmd->resp));
645 	cmd->retries = retries;
646 
647 	mrq.cmd = cmd;
648 	cmd->data = NULL;
649 
650 	mmc_wait_for_req(host, &mrq);
651 
652 	return cmd->error;
653 }
654 
655 EXPORT_SYMBOL(mmc_wait_for_cmd);
656 
657 /**
658  *	mmc_set_data_timeout - set the timeout for a data command
659  *	@data: data phase for command
660  *	@card: the MMC card associated with the data transfer
661  *
662  *	Computes the data timeout parameters according to the
663  *	correct algorithm given the card type.
664  */
665 void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card)
666 {
667 	unsigned int mult;
668 
669 	/*
670 	 * SDIO cards only define an upper 1 s limit on access.
671 	 */
672 	if (mmc_card_sdio(card)) {
673 		data->timeout_ns = 1000000000;
674 		data->timeout_clks = 0;
675 		return;
676 	}
677 
678 	/*
679 	 * SD cards use a 100 multiplier rather than 10
680 	 */
681 	mult = mmc_card_sd(card) ? 100 : 10;
682 
683 	/*
684 	 * Scale up the multiplier (and therefore the timeout) by
685 	 * the r2w factor for writes.
686 	 */
687 	if (data->flags & MMC_DATA_WRITE)
688 		mult <<= card->csd.r2w_factor;
689 
690 	data->timeout_ns = card->csd.taac_ns * mult;
691 	data->timeout_clks = card->csd.taac_clks * mult;
692 
693 	/*
694 	 * SD cards also have an upper limit on the timeout.
695 	 */
696 	if (mmc_card_sd(card)) {
697 		unsigned int timeout_us, limit_us;
698 
699 		timeout_us = data->timeout_ns / 1000;
700 		if (card->host->ios.clock)
701 			timeout_us += data->timeout_clks * 1000 /
702 				(card->host->ios.clock / 1000);
703 
704 		if (data->flags & MMC_DATA_WRITE)
705 			/*
706 			 * The MMC spec "It is strongly recommended
707 			 * for hosts to implement more than 500ms
708 			 * timeout value even if the card indicates
709 			 * the 250ms maximum busy length."  Even the
710 			 * previous value of 300ms is known to be
711 			 * insufficient for some cards.
712 			 */
713 			limit_us = 3000000;
714 		else
715 			limit_us = 100000;
716 
717 		/*
718 		 * SDHC cards always use these fixed values.
719 		 */
720 		if (timeout_us > limit_us) {
721 			data->timeout_ns = limit_us * 1000;
722 			data->timeout_clks = 0;
723 		}
724 
725 		/* assign limit value if invalid */
726 		if (timeout_us == 0)
727 			data->timeout_ns = limit_us * 1000;
728 	}
729 
730 	/*
731 	 * Some cards require longer data read timeout than indicated in CSD.
732 	 * Address this by setting the read timeout to a "reasonably high"
733 	 * value. For the cards tested, 600ms has proven enough. If necessary,
734 	 * this value can be increased if other problematic cards require this.
735 	 */
736 	if (mmc_card_long_read_time(card) && data->flags & MMC_DATA_READ) {
737 		data->timeout_ns = 600000000;
738 		data->timeout_clks = 0;
739 	}
740 
741 	/*
742 	 * Some cards need very high timeouts if driven in SPI mode.
743 	 * The worst observed timeout was 900ms after writing a
744 	 * continuous stream of data until the internal logic
745 	 * overflowed.
746 	 */
747 	if (mmc_host_is_spi(card->host)) {
748 		if (data->flags & MMC_DATA_WRITE) {
749 			if (data->timeout_ns < 1000000000)
750 				data->timeout_ns = 1000000000;	/* 1s */
751 		} else {
752 			if (data->timeout_ns < 100000000)
753 				data->timeout_ns =  100000000;	/* 100ms */
754 		}
755 	}
756 }
757 EXPORT_SYMBOL(mmc_set_data_timeout);
758 
759 /*
760  * Allow claiming an already claimed host if the context is the same or there is
761  * no context but the task is the same.
762  */
763 static inline bool mmc_ctx_matches(struct mmc_host *host, struct mmc_ctx *ctx,
764 				   struct task_struct *task)
765 {
766 	return host->claimer == ctx ||
767 	       (!ctx && task && host->claimer->task == task);
768 }
769 
770 static inline void mmc_ctx_set_claimer(struct mmc_host *host,
771 				       struct mmc_ctx *ctx,
772 				       struct task_struct *task)
773 {
774 	if (!host->claimer) {
775 		if (ctx)
776 			host->claimer = ctx;
777 		else
778 			host->claimer = &host->default_ctx;
779 	}
780 	if (task)
781 		host->claimer->task = task;
782 }
783 
784 /**
785  *	__mmc_claim_host - exclusively claim a host
786  *	@host: mmc host to claim
787  *	@ctx: context that claims the host or NULL in which case the default
788  *	context will be used
789  *	@abort: whether or not the operation should be aborted
790  *
791  *	Claim a host for a set of operations.  If @abort is non null and
792  *	dereference a non-zero value then this will return prematurely with
793  *	that non-zero value without acquiring the lock.  Returns zero
794  *	with the lock held otherwise.
795  */
796 int __mmc_claim_host(struct mmc_host *host, struct mmc_ctx *ctx,
797 		     atomic_t *abort)
798 {
799 	struct task_struct *task = ctx ? NULL : current;
800 	DECLARE_WAITQUEUE(wait, current);
801 	unsigned long flags;
802 	int stop;
803 	bool pm = false;
804 
805 	might_sleep();
806 
807 	add_wait_queue(&host->wq, &wait);
808 	spin_lock_irqsave(&host->lock, flags);
809 	while (1) {
810 		set_current_state(TASK_UNINTERRUPTIBLE);
811 		stop = abort ? atomic_read(abort) : 0;
812 		if (stop || !host->claimed || mmc_ctx_matches(host, ctx, task))
813 			break;
814 		spin_unlock_irqrestore(&host->lock, flags);
815 		schedule();
816 		spin_lock_irqsave(&host->lock, flags);
817 	}
818 	set_current_state(TASK_RUNNING);
819 	if (!stop) {
820 		host->claimed = 1;
821 		mmc_ctx_set_claimer(host, ctx, task);
822 		host->claim_cnt += 1;
823 		if (host->claim_cnt == 1)
824 			pm = true;
825 	} else
826 		wake_up(&host->wq);
827 	spin_unlock_irqrestore(&host->lock, flags);
828 	remove_wait_queue(&host->wq, &wait);
829 
830 	if (pm)
831 		pm_runtime_get_sync(mmc_dev(host));
832 
833 	return stop;
834 }
835 EXPORT_SYMBOL(__mmc_claim_host);
836 
837 /**
838  *	mmc_release_host - release a host
839  *	@host: mmc host to release
840  *
841  *	Release a MMC host, allowing others to claim the host
842  *	for their operations.
843  */
844 void mmc_release_host(struct mmc_host *host)
845 {
846 	unsigned long flags;
847 
848 	WARN_ON(!host->claimed);
849 
850 	spin_lock_irqsave(&host->lock, flags);
851 	if (--host->claim_cnt) {
852 		/* Release for nested claim */
853 		spin_unlock_irqrestore(&host->lock, flags);
854 	} else {
855 		host->claimed = 0;
856 		host->claimer->task = NULL;
857 		host->claimer = NULL;
858 		spin_unlock_irqrestore(&host->lock, flags);
859 		wake_up(&host->wq);
860 		pm_runtime_mark_last_busy(mmc_dev(host));
861 		if (host->caps & MMC_CAP_SYNC_RUNTIME_PM)
862 			pm_runtime_put_sync_suspend(mmc_dev(host));
863 		else
864 			pm_runtime_put_autosuspend(mmc_dev(host));
865 	}
866 }
867 EXPORT_SYMBOL(mmc_release_host);
868 
869 /*
870  * This is a helper function, which fetches a runtime pm reference for the
871  * card device and also claims the host.
872  */
873 void mmc_get_card(struct mmc_card *card, struct mmc_ctx *ctx)
874 {
875 	pm_runtime_get_sync(&card->dev);
876 	__mmc_claim_host(card->host, ctx, NULL);
877 }
878 EXPORT_SYMBOL(mmc_get_card);
879 
880 /*
881  * This is a helper function, which releases the host and drops the runtime
882  * pm reference for the card device.
883  */
884 void mmc_put_card(struct mmc_card *card, struct mmc_ctx *ctx)
885 {
886 	struct mmc_host *host = card->host;
887 
888 	WARN_ON(ctx && host->claimer != ctx);
889 
890 	mmc_release_host(host);
891 	pm_runtime_mark_last_busy(&card->dev);
892 	pm_runtime_put_autosuspend(&card->dev);
893 }
894 EXPORT_SYMBOL(mmc_put_card);
895 
896 /*
897  * Internal function that does the actual ios call to the host driver,
898  * optionally printing some debug output.
899  */
900 static inline void mmc_set_ios(struct mmc_host *host)
901 {
902 	struct mmc_ios *ios = &host->ios;
903 
904 	pr_debug("%s: clock %uHz busmode %u powermode %u cs %u Vdd %u "
905 		"width %u timing %u\n",
906 		 mmc_hostname(host), ios->clock, ios->bus_mode,
907 		 ios->power_mode, ios->chip_select, ios->vdd,
908 		 1 << ios->bus_width, ios->timing);
909 
910 	host->ops->set_ios(host, ios);
911 }
912 
913 /*
914  * Control chip select pin on a host.
915  */
916 void mmc_set_chip_select(struct mmc_host *host, int mode)
917 {
918 	host->ios.chip_select = mode;
919 	mmc_set_ios(host);
920 }
921 
922 /*
923  * Sets the host clock to the highest possible frequency that
924  * is below "hz".
925  */
926 void mmc_set_clock(struct mmc_host *host, unsigned int hz)
927 {
928 	WARN_ON(hz && hz < host->f_min);
929 
930 	if (hz > host->f_max)
931 		hz = host->f_max;
932 
933 	host->ios.clock = hz;
934 	mmc_set_ios(host);
935 }
936 
937 int mmc_execute_tuning(struct mmc_card *card)
938 {
939 	struct mmc_host *host = card->host;
940 	u32 opcode;
941 	int err;
942 
943 	if (!host->ops->execute_tuning)
944 		return 0;
945 
946 	if (host->cqe_on)
947 		host->cqe_ops->cqe_off(host);
948 
949 	if (mmc_card_mmc(card))
950 		opcode = MMC_SEND_TUNING_BLOCK_HS200;
951 	else
952 		opcode = MMC_SEND_TUNING_BLOCK;
953 
954 	err = host->ops->execute_tuning(host, opcode);
955 
956 	if (err)
957 		pr_err("%s: tuning execution failed: %d\n",
958 			mmc_hostname(host), err);
959 	else
960 		mmc_retune_enable(host);
961 
962 	return err;
963 }
964 
965 /*
966  * Change the bus mode (open drain/push-pull) of a host.
967  */
968 void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode)
969 {
970 	host->ios.bus_mode = mode;
971 	mmc_set_ios(host);
972 }
973 
974 /*
975  * Change data bus width of a host.
976  */
977 void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
978 {
979 	host->ios.bus_width = width;
980 	mmc_set_ios(host);
981 }
982 
983 /*
984  * Set initial state after a power cycle or a hw_reset.
985  */
986 void mmc_set_initial_state(struct mmc_host *host)
987 {
988 	if (host->cqe_on)
989 		host->cqe_ops->cqe_off(host);
990 
991 	mmc_retune_disable(host);
992 
993 	if (mmc_host_is_spi(host))
994 		host->ios.chip_select = MMC_CS_HIGH;
995 	else
996 		host->ios.chip_select = MMC_CS_DONTCARE;
997 	host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
998 	host->ios.bus_width = MMC_BUS_WIDTH_1;
999 	host->ios.timing = MMC_TIMING_LEGACY;
1000 	host->ios.drv_type = 0;
1001 	host->ios.enhanced_strobe = false;
1002 
1003 	/*
1004 	 * Make sure we are in non-enhanced strobe mode before we
1005 	 * actually enable it in ext_csd.
1006 	 */
1007 	if ((host->caps2 & MMC_CAP2_HS400_ES) &&
1008 	     host->ops->hs400_enhanced_strobe)
1009 		host->ops->hs400_enhanced_strobe(host, &host->ios);
1010 
1011 	mmc_set_ios(host);
1012 }
1013 
1014 /**
1015  * mmc_vdd_to_ocrbitnum - Convert a voltage to the OCR bit number
1016  * @vdd:	voltage (mV)
1017  * @low_bits:	prefer low bits in boundary cases
1018  *
1019  * This function returns the OCR bit number according to the provided @vdd
1020  * value. If conversion is not possible a negative errno value returned.
1021  *
1022  * Depending on the @low_bits flag the function prefers low or high OCR bits
1023  * on boundary voltages. For example,
1024  * with @low_bits = true, 3300 mV translates to ilog2(MMC_VDD_32_33);
1025  * with @low_bits = false, 3300 mV translates to ilog2(MMC_VDD_33_34);
1026  *
1027  * Any value in the [1951:1999] range translates to the ilog2(MMC_VDD_20_21).
1028  */
1029 static int mmc_vdd_to_ocrbitnum(int vdd, bool low_bits)
1030 {
1031 	const int max_bit = ilog2(MMC_VDD_35_36);
1032 	int bit;
1033 
1034 	if (vdd < 1650 || vdd > 3600)
1035 		return -EINVAL;
1036 
1037 	if (vdd >= 1650 && vdd <= 1950)
1038 		return ilog2(MMC_VDD_165_195);
1039 
1040 	if (low_bits)
1041 		vdd -= 1;
1042 
1043 	/* Base 2000 mV, step 100 mV, bit's base 8. */
1044 	bit = (vdd - 2000) / 100 + 8;
1045 	if (bit > max_bit)
1046 		return max_bit;
1047 	return bit;
1048 }
1049 
1050 /**
1051  * mmc_vddrange_to_ocrmask - Convert a voltage range to the OCR mask
1052  * @vdd_min:	minimum voltage value (mV)
1053  * @vdd_max:	maximum voltage value (mV)
1054  *
1055  * This function returns the OCR mask bits according to the provided @vdd_min
1056  * and @vdd_max values. If conversion is not possible the function returns 0.
1057  *
1058  * Notes wrt boundary cases:
1059  * This function sets the OCR bits for all boundary voltages, for example
1060  * [3300:3400] range is translated to MMC_VDD_32_33 | MMC_VDD_33_34 |
1061  * MMC_VDD_34_35 mask.
1062  */
1063 u32 mmc_vddrange_to_ocrmask(int vdd_min, int vdd_max)
1064 {
1065 	u32 mask = 0;
1066 
1067 	if (vdd_max < vdd_min)
1068 		return 0;
1069 
1070 	/* Prefer high bits for the boundary vdd_max values. */
1071 	vdd_max = mmc_vdd_to_ocrbitnum(vdd_max, false);
1072 	if (vdd_max < 0)
1073 		return 0;
1074 
1075 	/* Prefer low bits for the boundary vdd_min values. */
1076 	vdd_min = mmc_vdd_to_ocrbitnum(vdd_min, true);
1077 	if (vdd_min < 0)
1078 		return 0;
1079 
1080 	/* Fill the mask, from max bit to min bit. */
1081 	while (vdd_max >= vdd_min)
1082 		mask |= 1 << vdd_max--;
1083 
1084 	return mask;
1085 }
1086 
1087 static int mmc_of_get_func_num(struct device_node *node)
1088 {
1089 	u32 reg;
1090 	int ret;
1091 
1092 	ret = of_property_read_u32(node, "reg", &reg);
1093 	if (ret < 0)
1094 		return ret;
1095 
1096 	return reg;
1097 }
1098 
1099 struct device_node *mmc_of_find_child_device(struct mmc_host *host,
1100 		unsigned func_num)
1101 {
1102 	struct device_node *node;
1103 
1104 	if (!host->parent || !host->parent->of_node)
1105 		return NULL;
1106 
1107 	for_each_child_of_node(host->parent->of_node, node) {
1108 		if (mmc_of_get_func_num(node) == func_num)
1109 			return node;
1110 	}
1111 
1112 	return NULL;
1113 }
1114 
1115 /*
1116  * Mask off any voltages we don't support and select
1117  * the lowest voltage
1118  */
1119 u32 mmc_select_voltage(struct mmc_host *host, u32 ocr)
1120 {
1121 	int bit;
1122 
1123 	/*
1124 	 * Sanity check the voltages that the card claims to
1125 	 * support.
1126 	 */
1127 	if (ocr & 0x7F) {
1128 		dev_warn(mmc_dev(host),
1129 		"card claims to support voltages below defined range\n");
1130 		ocr &= ~0x7F;
1131 	}
1132 
1133 	ocr &= host->ocr_avail;
1134 	if (!ocr) {
1135 		dev_warn(mmc_dev(host), "no support for card's volts\n");
1136 		return 0;
1137 	}
1138 
1139 	if (host->caps2 & MMC_CAP2_FULL_PWR_CYCLE) {
1140 		bit = ffs(ocr) - 1;
1141 		ocr &= 3 << bit;
1142 		mmc_power_cycle(host, ocr);
1143 	} else {
1144 		bit = fls(ocr) - 1;
1145 		ocr &= 3 << bit;
1146 		if (bit != host->ios.vdd)
1147 			dev_warn(mmc_dev(host), "exceeding card's volts\n");
1148 	}
1149 
1150 	return ocr;
1151 }
1152 
1153 int mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage)
1154 {
1155 	int err = 0;
1156 	int old_signal_voltage = host->ios.signal_voltage;
1157 
1158 	host->ios.signal_voltage = signal_voltage;
1159 	if (host->ops->start_signal_voltage_switch)
1160 		err = host->ops->start_signal_voltage_switch(host, &host->ios);
1161 
1162 	if (err)
1163 		host->ios.signal_voltage = old_signal_voltage;
1164 
1165 	return err;
1166 
1167 }
1168 
1169 void mmc_set_initial_signal_voltage(struct mmc_host *host)
1170 {
1171 	/* Try to set signal voltage to 3.3V but fall back to 1.8v or 1.2v */
1172 	if (!mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330))
1173 		dev_dbg(mmc_dev(host), "Initial signal voltage of 3.3v\n");
1174 	else if (!mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180))
1175 		dev_dbg(mmc_dev(host), "Initial signal voltage of 1.8v\n");
1176 	else if (!mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120))
1177 		dev_dbg(mmc_dev(host), "Initial signal voltage of 1.2v\n");
1178 }
1179 
1180 int mmc_host_set_uhs_voltage(struct mmc_host *host)
1181 {
1182 	u32 clock;
1183 
1184 	/*
1185 	 * During a signal voltage level switch, the clock must be gated
1186 	 * for 5 ms according to the SD spec
1187 	 */
1188 	clock = host->ios.clock;
1189 	host->ios.clock = 0;
1190 	mmc_set_ios(host);
1191 
1192 	if (mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180))
1193 		return -EAGAIN;
1194 
1195 	/* Keep clock gated for at least 10 ms, though spec only says 5 ms */
1196 	mmc_delay(10);
1197 	host->ios.clock = clock;
1198 	mmc_set_ios(host);
1199 
1200 	return 0;
1201 }
1202 
1203 int mmc_set_uhs_voltage(struct mmc_host *host, u32 ocr)
1204 {
1205 	struct mmc_command cmd = {};
1206 	int err = 0;
1207 
1208 	/*
1209 	 * If we cannot switch voltages, return failure so the caller
1210 	 * can continue without UHS mode
1211 	 */
1212 	if (!host->ops->start_signal_voltage_switch)
1213 		return -EPERM;
1214 	if (!host->ops->card_busy)
1215 		pr_warn("%s: cannot verify signal voltage switch\n",
1216 			mmc_hostname(host));
1217 
1218 	cmd.opcode = SD_SWITCH_VOLTAGE;
1219 	cmd.arg = 0;
1220 	cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
1221 
1222 	err = mmc_wait_for_cmd(host, &cmd, 0);
1223 	if (err)
1224 		return err;
1225 
1226 	if (!mmc_host_is_spi(host) && (cmd.resp[0] & R1_ERROR))
1227 		return -EIO;
1228 
1229 	/*
1230 	 * The card should drive cmd and dat[0:3] low immediately
1231 	 * after the response of cmd11, but wait 1 ms to be sure
1232 	 */
1233 	mmc_delay(1);
1234 	if (host->ops->card_busy && !host->ops->card_busy(host)) {
1235 		err = -EAGAIN;
1236 		goto power_cycle;
1237 	}
1238 
1239 	if (mmc_host_set_uhs_voltage(host)) {
1240 		/*
1241 		 * Voltages may not have been switched, but we've already
1242 		 * sent CMD11, so a power cycle is required anyway
1243 		 */
1244 		err = -EAGAIN;
1245 		goto power_cycle;
1246 	}
1247 
1248 	/* Wait for at least 1 ms according to spec */
1249 	mmc_delay(1);
1250 
1251 	/*
1252 	 * Failure to switch is indicated by the card holding
1253 	 * dat[0:3] low
1254 	 */
1255 	if (host->ops->card_busy && host->ops->card_busy(host))
1256 		err = -EAGAIN;
1257 
1258 power_cycle:
1259 	if (err) {
1260 		pr_debug("%s: Signal voltage switch failed, "
1261 			"power cycling card\n", mmc_hostname(host));
1262 		mmc_power_cycle(host, ocr);
1263 	}
1264 
1265 	return err;
1266 }
1267 
1268 /*
1269  * Select timing parameters for host.
1270  */
1271 void mmc_set_timing(struct mmc_host *host, unsigned int timing)
1272 {
1273 	host->ios.timing = timing;
1274 	mmc_set_ios(host);
1275 }
1276 
1277 /*
1278  * Select appropriate driver type for host.
1279  */
1280 void mmc_set_driver_type(struct mmc_host *host, unsigned int drv_type)
1281 {
1282 	host->ios.drv_type = drv_type;
1283 	mmc_set_ios(host);
1284 }
1285 
1286 int mmc_select_drive_strength(struct mmc_card *card, unsigned int max_dtr,
1287 			      int card_drv_type, int *drv_type)
1288 {
1289 	struct mmc_host *host = card->host;
1290 	int host_drv_type = SD_DRIVER_TYPE_B;
1291 
1292 	*drv_type = 0;
1293 
1294 	if (!host->ops->select_drive_strength)
1295 		return 0;
1296 
1297 	/* Use SD definition of driver strength for hosts */
1298 	if (host->caps & MMC_CAP_DRIVER_TYPE_A)
1299 		host_drv_type |= SD_DRIVER_TYPE_A;
1300 
1301 	if (host->caps & MMC_CAP_DRIVER_TYPE_C)
1302 		host_drv_type |= SD_DRIVER_TYPE_C;
1303 
1304 	if (host->caps & MMC_CAP_DRIVER_TYPE_D)
1305 		host_drv_type |= SD_DRIVER_TYPE_D;
1306 
1307 	/*
1308 	 * The drive strength that the hardware can support
1309 	 * depends on the board design.  Pass the appropriate
1310 	 * information and let the hardware specific code
1311 	 * return what is possible given the options
1312 	 */
1313 	return host->ops->select_drive_strength(card, max_dtr,
1314 						host_drv_type,
1315 						card_drv_type,
1316 						drv_type);
1317 }
1318 
1319 /*
1320  * Apply power to the MMC stack.  This is a two-stage process.
1321  * First, we enable power to the card without the clock running.
1322  * We then wait a bit for the power to stabilise.  Finally,
1323  * enable the bus drivers and clock to the card.
1324  *
1325  * We must _NOT_ enable the clock prior to power stablising.
1326  *
1327  * If a host does all the power sequencing itself, ignore the
1328  * initial MMC_POWER_UP stage.
1329  */
1330 void mmc_power_up(struct mmc_host *host, u32 ocr)
1331 {
1332 	if (host->ios.power_mode == MMC_POWER_ON)
1333 		return;
1334 
1335 	mmc_pwrseq_pre_power_on(host);
1336 
1337 	host->ios.vdd = fls(ocr) - 1;
1338 	host->ios.power_mode = MMC_POWER_UP;
1339 	/* Set initial state and call mmc_set_ios */
1340 	mmc_set_initial_state(host);
1341 
1342 	mmc_set_initial_signal_voltage(host);
1343 
1344 	/*
1345 	 * This delay should be sufficient to allow the power supply
1346 	 * to reach the minimum voltage.
1347 	 */
1348 	mmc_delay(host->ios.power_delay_ms);
1349 
1350 	mmc_pwrseq_post_power_on(host);
1351 
1352 	host->ios.clock = host->f_init;
1353 
1354 	host->ios.power_mode = MMC_POWER_ON;
1355 	mmc_set_ios(host);
1356 
1357 	/*
1358 	 * This delay must be at least 74 clock sizes, or 1 ms, or the
1359 	 * time required to reach a stable voltage.
1360 	 */
1361 	mmc_delay(host->ios.power_delay_ms);
1362 }
1363 
1364 void mmc_power_off(struct mmc_host *host)
1365 {
1366 	if (host->ios.power_mode == MMC_POWER_OFF)
1367 		return;
1368 
1369 	mmc_pwrseq_power_off(host);
1370 
1371 	host->ios.clock = 0;
1372 	host->ios.vdd = 0;
1373 
1374 	host->ios.power_mode = MMC_POWER_OFF;
1375 	/* Set initial state and call mmc_set_ios */
1376 	mmc_set_initial_state(host);
1377 
1378 	/*
1379 	 * Some configurations, such as the 802.11 SDIO card in the OLPC
1380 	 * XO-1.5, require a short delay after poweroff before the card
1381 	 * can be successfully turned on again.
1382 	 */
1383 	mmc_delay(1);
1384 }
1385 
1386 void mmc_power_cycle(struct mmc_host *host, u32 ocr)
1387 {
1388 	mmc_power_off(host);
1389 	/* Wait at least 1 ms according to SD spec */
1390 	mmc_delay(1);
1391 	mmc_power_up(host, ocr);
1392 }
1393 
1394 /*
1395  * Cleanup when the last reference to the bus operator is dropped.
1396  */
1397 static void __mmc_release_bus(struct mmc_host *host)
1398 {
1399 	WARN_ON(!host->bus_dead);
1400 
1401 	host->bus_ops = NULL;
1402 }
1403 
1404 /*
1405  * Increase reference count of bus operator
1406  */
1407 static inline void mmc_bus_get(struct mmc_host *host)
1408 {
1409 	unsigned long flags;
1410 
1411 	spin_lock_irqsave(&host->lock, flags);
1412 	host->bus_refs++;
1413 	spin_unlock_irqrestore(&host->lock, flags);
1414 }
1415 
1416 /*
1417  * Decrease reference count of bus operator and free it if
1418  * it is the last reference.
1419  */
1420 static inline void mmc_bus_put(struct mmc_host *host)
1421 {
1422 	unsigned long flags;
1423 
1424 	spin_lock_irqsave(&host->lock, flags);
1425 	host->bus_refs--;
1426 	if ((host->bus_refs == 0) && host->bus_ops)
1427 		__mmc_release_bus(host);
1428 	spin_unlock_irqrestore(&host->lock, flags);
1429 }
1430 
1431 /*
1432  * Assign a mmc bus handler to a host. Only one bus handler may control a
1433  * host at any given time.
1434  */
1435 void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops)
1436 {
1437 	unsigned long flags;
1438 
1439 	WARN_ON(!host->claimed);
1440 
1441 	spin_lock_irqsave(&host->lock, flags);
1442 
1443 	WARN_ON(host->bus_ops);
1444 	WARN_ON(host->bus_refs);
1445 
1446 	host->bus_ops = ops;
1447 	host->bus_refs = 1;
1448 	host->bus_dead = 0;
1449 
1450 	spin_unlock_irqrestore(&host->lock, flags);
1451 }
1452 
1453 /*
1454  * Remove the current bus handler from a host.
1455  */
1456 void mmc_detach_bus(struct mmc_host *host)
1457 {
1458 	unsigned long flags;
1459 
1460 	WARN_ON(!host->claimed);
1461 	WARN_ON(!host->bus_ops);
1462 
1463 	spin_lock_irqsave(&host->lock, flags);
1464 
1465 	host->bus_dead = 1;
1466 
1467 	spin_unlock_irqrestore(&host->lock, flags);
1468 
1469 	mmc_bus_put(host);
1470 }
1471 
1472 void _mmc_detect_change(struct mmc_host *host, unsigned long delay, bool cd_irq)
1473 {
1474 	/*
1475 	 * If the device is configured as wakeup, we prevent a new sleep for
1476 	 * 5 s to give provision for user space to consume the event.
1477 	 */
1478 	if (cd_irq && !(host->caps & MMC_CAP_NEEDS_POLL) &&
1479 		device_can_wakeup(mmc_dev(host)))
1480 		pm_wakeup_event(mmc_dev(host), 5000);
1481 
1482 	host->detect_change = 1;
1483 	mmc_schedule_delayed_work(&host->detect, delay);
1484 }
1485 
1486 /**
1487  *	mmc_detect_change - process change of state on a MMC socket
1488  *	@host: host which changed state.
1489  *	@delay: optional delay to wait before detection (jiffies)
1490  *
1491  *	MMC drivers should call this when they detect a card has been
1492  *	inserted or removed. The MMC layer will confirm that any
1493  *	present card is still functional, and initialize any newly
1494  *	inserted.
1495  */
1496 void mmc_detect_change(struct mmc_host *host, unsigned long delay)
1497 {
1498 	_mmc_detect_change(host, delay, true);
1499 }
1500 EXPORT_SYMBOL(mmc_detect_change);
1501 
1502 void mmc_init_erase(struct mmc_card *card)
1503 {
1504 	unsigned int sz;
1505 
1506 	if (is_power_of_2(card->erase_size))
1507 		card->erase_shift = ffs(card->erase_size) - 1;
1508 	else
1509 		card->erase_shift = 0;
1510 
1511 	/*
1512 	 * It is possible to erase an arbitrarily large area of an SD or MMC
1513 	 * card.  That is not desirable because it can take a long time
1514 	 * (minutes) potentially delaying more important I/O, and also the
1515 	 * timeout calculations become increasingly hugely over-estimated.
1516 	 * Consequently, 'pref_erase' is defined as a guide to limit erases
1517 	 * to that size and alignment.
1518 	 *
1519 	 * For SD cards that define Allocation Unit size, limit erases to one
1520 	 * Allocation Unit at a time.
1521 	 * For MMC, have a stab at ai good value and for modern cards it will
1522 	 * end up being 4MiB. Note that if the value is too small, it can end
1523 	 * up taking longer to erase. Also note, erase_size is already set to
1524 	 * High Capacity Erase Size if available when this function is called.
1525 	 */
1526 	if (mmc_card_sd(card) && card->ssr.au) {
1527 		card->pref_erase = card->ssr.au;
1528 		card->erase_shift = ffs(card->ssr.au) - 1;
1529 	} else if (card->erase_size) {
1530 		sz = (card->csd.capacity << (card->csd.read_blkbits - 9)) >> 11;
1531 		if (sz < 128)
1532 			card->pref_erase = 512 * 1024 / 512;
1533 		else if (sz < 512)
1534 			card->pref_erase = 1024 * 1024 / 512;
1535 		else if (sz < 1024)
1536 			card->pref_erase = 2 * 1024 * 1024 / 512;
1537 		else
1538 			card->pref_erase = 4 * 1024 * 1024 / 512;
1539 		if (card->pref_erase < card->erase_size)
1540 			card->pref_erase = card->erase_size;
1541 		else {
1542 			sz = card->pref_erase % card->erase_size;
1543 			if (sz)
1544 				card->pref_erase += card->erase_size - sz;
1545 		}
1546 	} else
1547 		card->pref_erase = 0;
1548 }
1549 
1550 static unsigned int mmc_mmc_erase_timeout(struct mmc_card *card,
1551 				          unsigned int arg, unsigned int qty)
1552 {
1553 	unsigned int erase_timeout;
1554 
1555 	if (arg == MMC_DISCARD_ARG ||
1556 	    (arg == MMC_TRIM_ARG && card->ext_csd.rev >= 6)) {
1557 		erase_timeout = card->ext_csd.trim_timeout;
1558 	} else if (card->ext_csd.erase_group_def & 1) {
1559 		/* High Capacity Erase Group Size uses HC timeouts */
1560 		if (arg == MMC_TRIM_ARG)
1561 			erase_timeout = card->ext_csd.trim_timeout;
1562 		else
1563 			erase_timeout = card->ext_csd.hc_erase_timeout;
1564 	} else {
1565 		/* CSD Erase Group Size uses write timeout */
1566 		unsigned int mult = (10 << card->csd.r2w_factor);
1567 		unsigned int timeout_clks = card->csd.taac_clks * mult;
1568 		unsigned int timeout_us;
1569 
1570 		/* Avoid overflow: e.g. taac_ns=80000000 mult=1280 */
1571 		if (card->csd.taac_ns < 1000000)
1572 			timeout_us = (card->csd.taac_ns * mult) / 1000;
1573 		else
1574 			timeout_us = (card->csd.taac_ns / 1000) * mult;
1575 
1576 		/*
1577 		 * ios.clock is only a target.  The real clock rate might be
1578 		 * less but not that much less, so fudge it by multiplying by 2.
1579 		 */
1580 		timeout_clks <<= 1;
1581 		timeout_us += (timeout_clks * 1000) /
1582 			      (card->host->ios.clock / 1000);
1583 
1584 		erase_timeout = timeout_us / 1000;
1585 
1586 		/*
1587 		 * Theoretically, the calculation could underflow so round up
1588 		 * to 1ms in that case.
1589 		 */
1590 		if (!erase_timeout)
1591 			erase_timeout = 1;
1592 	}
1593 
1594 	/* Multiplier for secure operations */
1595 	if (arg & MMC_SECURE_ARGS) {
1596 		if (arg == MMC_SECURE_ERASE_ARG)
1597 			erase_timeout *= card->ext_csd.sec_erase_mult;
1598 		else
1599 			erase_timeout *= card->ext_csd.sec_trim_mult;
1600 	}
1601 
1602 	erase_timeout *= qty;
1603 
1604 	/*
1605 	 * Ensure at least a 1 second timeout for SPI as per
1606 	 * 'mmc_set_data_timeout()'
1607 	 */
1608 	if (mmc_host_is_spi(card->host) && erase_timeout < 1000)
1609 		erase_timeout = 1000;
1610 
1611 	return erase_timeout;
1612 }
1613 
1614 static unsigned int mmc_sd_erase_timeout(struct mmc_card *card,
1615 					 unsigned int arg,
1616 					 unsigned int qty)
1617 {
1618 	unsigned int erase_timeout;
1619 
1620 	/* for DISCARD none of the below calculation applies.
1621 	 * the busy timeout is 250msec per discard command.
1622 	 */
1623 	if (arg == SD_DISCARD_ARG)
1624 		return SD_DISCARD_TIMEOUT_MS;
1625 
1626 	if (card->ssr.erase_timeout) {
1627 		/* Erase timeout specified in SD Status Register (SSR) */
1628 		erase_timeout = card->ssr.erase_timeout * qty +
1629 				card->ssr.erase_offset;
1630 	} else {
1631 		/*
1632 		 * Erase timeout not specified in SD Status Register (SSR) so
1633 		 * use 250ms per write block.
1634 		 */
1635 		erase_timeout = 250 * qty;
1636 	}
1637 
1638 	/* Must not be less than 1 second */
1639 	if (erase_timeout < 1000)
1640 		erase_timeout = 1000;
1641 
1642 	return erase_timeout;
1643 }
1644 
1645 static unsigned int mmc_erase_timeout(struct mmc_card *card,
1646 				      unsigned int arg,
1647 				      unsigned int qty)
1648 {
1649 	if (mmc_card_sd(card))
1650 		return mmc_sd_erase_timeout(card, arg, qty);
1651 	else
1652 		return mmc_mmc_erase_timeout(card, arg, qty);
1653 }
1654 
1655 static int mmc_do_erase(struct mmc_card *card, unsigned int from,
1656 			unsigned int to, unsigned int arg)
1657 {
1658 	struct mmc_command cmd = {};
1659 	unsigned int qty = 0, busy_timeout = 0;
1660 	bool use_r1b_resp = false;
1661 	unsigned long timeout;
1662 	int loop_udelay=64, udelay_max=32768;
1663 	int err;
1664 
1665 	mmc_retune_hold(card->host);
1666 
1667 	/*
1668 	 * qty is used to calculate the erase timeout which depends on how many
1669 	 * erase groups (or allocation units in SD terminology) are affected.
1670 	 * We count erasing part of an erase group as one erase group.
1671 	 * For SD, the allocation units are always a power of 2.  For MMC, the
1672 	 * erase group size is almost certainly also power of 2, but it does not
1673 	 * seem to insist on that in the JEDEC standard, so we fall back to
1674 	 * division in that case.  SD may not specify an allocation unit size,
1675 	 * in which case the timeout is based on the number of write blocks.
1676 	 *
1677 	 * Note that the timeout for secure trim 2 will only be correct if the
1678 	 * number of erase groups specified is the same as the total of all
1679 	 * preceding secure trim 1 commands.  Since the power may have been
1680 	 * lost since the secure trim 1 commands occurred, it is generally
1681 	 * impossible to calculate the secure trim 2 timeout correctly.
1682 	 */
1683 	if (card->erase_shift)
1684 		qty += ((to >> card->erase_shift) -
1685 			(from >> card->erase_shift)) + 1;
1686 	else if (mmc_card_sd(card))
1687 		qty += to - from + 1;
1688 	else
1689 		qty += ((to / card->erase_size) -
1690 			(from / card->erase_size)) + 1;
1691 
1692 	if (!mmc_card_blockaddr(card)) {
1693 		from <<= 9;
1694 		to <<= 9;
1695 	}
1696 
1697 	if (mmc_card_sd(card))
1698 		cmd.opcode = SD_ERASE_WR_BLK_START;
1699 	else
1700 		cmd.opcode = MMC_ERASE_GROUP_START;
1701 	cmd.arg = from;
1702 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
1703 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
1704 	if (err) {
1705 		pr_err("mmc_erase: group start error %d, "
1706 		       "status %#x\n", err, cmd.resp[0]);
1707 		err = -EIO;
1708 		goto out;
1709 	}
1710 
1711 	memset(&cmd, 0, sizeof(struct mmc_command));
1712 	if (mmc_card_sd(card))
1713 		cmd.opcode = SD_ERASE_WR_BLK_END;
1714 	else
1715 		cmd.opcode = MMC_ERASE_GROUP_END;
1716 	cmd.arg = to;
1717 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
1718 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
1719 	if (err) {
1720 		pr_err("mmc_erase: group end error %d, status %#x\n",
1721 		       err, cmd.resp[0]);
1722 		err = -EIO;
1723 		goto out;
1724 	}
1725 
1726 	memset(&cmd, 0, sizeof(struct mmc_command));
1727 	cmd.opcode = MMC_ERASE;
1728 	cmd.arg = arg;
1729 	busy_timeout = mmc_erase_timeout(card, arg, qty);
1730 	/*
1731 	 * If the host controller supports busy signalling and the timeout for
1732 	 * the erase operation does not exceed the max_busy_timeout, we should
1733 	 * use R1B response. Or we need to prevent the host from doing hw busy
1734 	 * detection, which is done by converting to a R1 response instead.
1735 	 */
1736 	if (card->host->max_busy_timeout &&
1737 	    busy_timeout > card->host->max_busy_timeout) {
1738 		cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
1739 	} else {
1740 		cmd.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
1741 		cmd.busy_timeout = busy_timeout;
1742 		use_r1b_resp = true;
1743 	}
1744 
1745 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
1746 	if (err) {
1747 		pr_err("mmc_erase: erase error %d, status %#x\n",
1748 		       err, cmd.resp[0]);
1749 		err = -EIO;
1750 		goto out;
1751 	}
1752 
1753 	if (mmc_host_is_spi(card->host))
1754 		goto out;
1755 
1756 	/*
1757 	 * In case of when R1B + MMC_CAP_WAIT_WHILE_BUSY is used, the polling
1758 	 * shall be avoided.
1759 	 */
1760 	if ((card->host->caps & MMC_CAP_WAIT_WHILE_BUSY) && use_r1b_resp)
1761 		goto out;
1762 
1763 	timeout = jiffies + msecs_to_jiffies(busy_timeout);
1764 	do {
1765 		memset(&cmd, 0, sizeof(struct mmc_command));
1766 		cmd.opcode = MMC_SEND_STATUS;
1767 		cmd.arg = card->rca << 16;
1768 		cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
1769 		/* Do not retry else we can't see errors */
1770 		err = mmc_wait_for_cmd(card->host, &cmd, 0);
1771 		if (err || R1_STATUS(cmd.resp[0])) {
1772 			pr_err("error %d requesting status %#x\n",
1773 				err, cmd.resp[0]);
1774 			err = -EIO;
1775 			goto out;
1776 		}
1777 
1778 		/* Timeout if the device never becomes ready for data and
1779 		 * never leaves the program state.
1780 		 */
1781 		if (time_after(jiffies, timeout)) {
1782 			pr_err("%s: Card stuck in programming state! %s\n",
1783 				mmc_hostname(card->host), __func__);
1784 			err =  -EIO;
1785 			goto out;
1786 		}
1787 		if ((cmd.resp[0] & R1_READY_FOR_DATA) &&
1788 		    R1_CURRENT_STATE(cmd.resp[0]) != R1_STATE_PRG)
1789 			break;
1790 
1791 		usleep_range(loop_udelay, loop_udelay*2);
1792 		if (loop_udelay < udelay_max)
1793 			loop_udelay *= 2;
1794 	} while (1);
1795 
1796 out:
1797 	mmc_retune_release(card->host);
1798 	return err;
1799 }
1800 
1801 static unsigned int mmc_align_erase_size(struct mmc_card *card,
1802 					 unsigned int *from,
1803 					 unsigned int *to,
1804 					 unsigned int nr)
1805 {
1806 	unsigned int from_new = *from, nr_new = nr, rem;
1807 
1808 	/*
1809 	 * When the 'card->erase_size' is power of 2, we can use round_up/down()
1810 	 * to align the erase size efficiently.
1811 	 */
1812 	if (is_power_of_2(card->erase_size)) {
1813 		unsigned int temp = from_new;
1814 
1815 		from_new = round_up(temp, card->erase_size);
1816 		rem = from_new - temp;
1817 
1818 		if (nr_new > rem)
1819 			nr_new -= rem;
1820 		else
1821 			return 0;
1822 
1823 		nr_new = round_down(nr_new, card->erase_size);
1824 	} else {
1825 		rem = from_new % card->erase_size;
1826 		if (rem) {
1827 			rem = card->erase_size - rem;
1828 			from_new += rem;
1829 			if (nr_new > rem)
1830 				nr_new -= rem;
1831 			else
1832 				return 0;
1833 		}
1834 
1835 		rem = nr_new % card->erase_size;
1836 		if (rem)
1837 			nr_new -= rem;
1838 	}
1839 
1840 	if (nr_new == 0)
1841 		return 0;
1842 
1843 	*to = from_new + nr_new;
1844 	*from = from_new;
1845 
1846 	return nr_new;
1847 }
1848 
1849 /**
1850  * mmc_erase - erase sectors.
1851  * @card: card to erase
1852  * @from: first sector to erase
1853  * @nr: number of sectors to erase
1854  * @arg: erase command argument
1855  *
1856  * Caller must claim host before calling this function.
1857  */
1858 int mmc_erase(struct mmc_card *card, unsigned int from, unsigned int nr,
1859 	      unsigned int arg)
1860 {
1861 	unsigned int rem, to = from + nr;
1862 	int err;
1863 
1864 	if (!(card->host->caps & MMC_CAP_ERASE) ||
1865 	    !(card->csd.cmdclass & CCC_ERASE))
1866 		return -EOPNOTSUPP;
1867 
1868 	if (!card->erase_size)
1869 		return -EOPNOTSUPP;
1870 
1871 	if (mmc_card_sd(card) && arg != SD_ERASE_ARG && arg != SD_DISCARD_ARG)
1872 		return -EOPNOTSUPP;
1873 
1874 	if (mmc_card_mmc(card) && (arg & MMC_SECURE_ARGS) &&
1875 	    !(card->ext_csd.sec_feature_support & EXT_CSD_SEC_ER_EN))
1876 		return -EOPNOTSUPP;
1877 
1878 	if (mmc_card_mmc(card) && (arg & MMC_TRIM_ARGS) &&
1879 	    !(card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN))
1880 		return -EOPNOTSUPP;
1881 
1882 	if (arg == MMC_SECURE_ERASE_ARG) {
1883 		if (from % card->erase_size || nr % card->erase_size)
1884 			return -EINVAL;
1885 	}
1886 
1887 	if (arg == MMC_ERASE_ARG)
1888 		nr = mmc_align_erase_size(card, &from, &to, nr);
1889 
1890 	if (nr == 0)
1891 		return 0;
1892 
1893 	if (to <= from)
1894 		return -EINVAL;
1895 
1896 	/* 'from' and 'to' are inclusive */
1897 	to -= 1;
1898 
1899 	/*
1900 	 * Special case where only one erase-group fits in the timeout budget:
1901 	 * If the region crosses an erase-group boundary on this particular
1902 	 * case, we will be trimming more than one erase-group which, does not
1903 	 * fit in the timeout budget of the controller, so we need to split it
1904 	 * and call mmc_do_erase() twice if necessary. This special case is
1905 	 * identified by the card->eg_boundary flag.
1906 	 */
1907 	rem = card->erase_size - (from % card->erase_size);
1908 	if ((arg & MMC_TRIM_ARGS) && (card->eg_boundary) && (nr > rem)) {
1909 		err = mmc_do_erase(card, from, from + rem - 1, arg);
1910 		from += rem;
1911 		if ((err) || (to <= from))
1912 			return err;
1913 	}
1914 
1915 	return mmc_do_erase(card, from, to, arg);
1916 }
1917 EXPORT_SYMBOL(mmc_erase);
1918 
1919 int mmc_can_erase(struct mmc_card *card)
1920 {
1921 	if ((card->host->caps & MMC_CAP_ERASE) &&
1922 	    (card->csd.cmdclass & CCC_ERASE) && card->erase_size)
1923 		return 1;
1924 	return 0;
1925 }
1926 EXPORT_SYMBOL(mmc_can_erase);
1927 
1928 int mmc_can_trim(struct mmc_card *card)
1929 {
1930 	if ((card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN) &&
1931 	    (!(card->quirks & MMC_QUIRK_TRIM_BROKEN)))
1932 		return 1;
1933 	return 0;
1934 }
1935 EXPORT_SYMBOL(mmc_can_trim);
1936 
1937 int mmc_can_discard(struct mmc_card *card)
1938 {
1939 	/*
1940 	 * As there's no way to detect the discard support bit at v4.5
1941 	 * use the s/w feature support filed.
1942 	 */
1943 	if (card->ext_csd.feature_support & MMC_DISCARD_FEATURE)
1944 		return 1;
1945 	return 0;
1946 }
1947 EXPORT_SYMBOL(mmc_can_discard);
1948 
1949 int mmc_can_sanitize(struct mmc_card *card)
1950 {
1951 	if (!mmc_can_trim(card) && !mmc_can_erase(card))
1952 		return 0;
1953 	if (card->ext_csd.sec_feature_support & EXT_CSD_SEC_SANITIZE)
1954 		return 1;
1955 	return 0;
1956 }
1957 EXPORT_SYMBOL(mmc_can_sanitize);
1958 
1959 int mmc_can_secure_erase_trim(struct mmc_card *card)
1960 {
1961 	if ((card->ext_csd.sec_feature_support & EXT_CSD_SEC_ER_EN) &&
1962 	    !(card->quirks & MMC_QUIRK_SEC_ERASE_TRIM_BROKEN))
1963 		return 1;
1964 	return 0;
1965 }
1966 EXPORT_SYMBOL(mmc_can_secure_erase_trim);
1967 
1968 int mmc_erase_group_aligned(struct mmc_card *card, unsigned int from,
1969 			    unsigned int nr)
1970 {
1971 	if (!card->erase_size)
1972 		return 0;
1973 	if (from % card->erase_size || nr % card->erase_size)
1974 		return 0;
1975 	return 1;
1976 }
1977 EXPORT_SYMBOL(mmc_erase_group_aligned);
1978 
1979 static unsigned int mmc_do_calc_max_discard(struct mmc_card *card,
1980 					    unsigned int arg)
1981 {
1982 	struct mmc_host *host = card->host;
1983 	unsigned int max_discard, x, y, qty = 0, max_qty, min_qty, timeout;
1984 	unsigned int last_timeout = 0;
1985 	unsigned int max_busy_timeout = host->max_busy_timeout ?
1986 			host->max_busy_timeout : MMC_ERASE_TIMEOUT_MS;
1987 
1988 	if (card->erase_shift) {
1989 		max_qty = UINT_MAX >> card->erase_shift;
1990 		min_qty = card->pref_erase >> card->erase_shift;
1991 	} else if (mmc_card_sd(card)) {
1992 		max_qty = UINT_MAX;
1993 		min_qty = card->pref_erase;
1994 	} else {
1995 		max_qty = UINT_MAX / card->erase_size;
1996 		min_qty = card->pref_erase / card->erase_size;
1997 	}
1998 
1999 	/*
2000 	 * We should not only use 'host->max_busy_timeout' as the limitation
2001 	 * when deciding the max discard sectors. We should set a balance value
2002 	 * to improve the erase speed, and it can not get too long timeout at
2003 	 * the same time.
2004 	 *
2005 	 * Here we set 'card->pref_erase' as the minimal discard sectors no
2006 	 * matter what size of 'host->max_busy_timeout', but if the
2007 	 * 'host->max_busy_timeout' is large enough for more discard sectors,
2008 	 * then we can continue to increase the max discard sectors until we
2009 	 * get a balance value. In cases when the 'host->max_busy_timeout'
2010 	 * isn't specified, use the default max erase timeout.
2011 	 */
2012 	do {
2013 		y = 0;
2014 		for (x = 1; x && x <= max_qty && max_qty - x >= qty; x <<= 1) {
2015 			timeout = mmc_erase_timeout(card, arg, qty + x);
2016 
2017 			if (qty + x > min_qty && timeout > max_busy_timeout)
2018 				break;
2019 
2020 			if (timeout < last_timeout)
2021 				break;
2022 			last_timeout = timeout;
2023 			y = x;
2024 		}
2025 		qty += y;
2026 	} while (y);
2027 
2028 	if (!qty)
2029 		return 0;
2030 
2031 	/*
2032 	 * When specifying a sector range to trim, chances are we might cross
2033 	 * an erase-group boundary even if the amount of sectors is less than
2034 	 * one erase-group.
2035 	 * If we can only fit one erase-group in the controller timeout budget,
2036 	 * we have to care that erase-group boundaries are not crossed by a
2037 	 * single trim operation. We flag that special case with "eg_boundary".
2038 	 * In all other cases we can just decrement qty and pretend that we
2039 	 * always touch (qty + 1) erase-groups as a simple optimization.
2040 	 */
2041 	if (qty == 1)
2042 		card->eg_boundary = 1;
2043 	else
2044 		qty--;
2045 
2046 	/* Convert qty to sectors */
2047 	if (card->erase_shift)
2048 		max_discard = qty << card->erase_shift;
2049 	else if (mmc_card_sd(card))
2050 		max_discard = qty + 1;
2051 	else
2052 		max_discard = qty * card->erase_size;
2053 
2054 	return max_discard;
2055 }
2056 
2057 unsigned int mmc_calc_max_discard(struct mmc_card *card)
2058 {
2059 	struct mmc_host *host = card->host;
2060 	unsigned int max_discard, max_trim;
2061 
2062 	/*
2063 	 * Without erase_group_def set, MMC erase timeout depends on clock
2064 	 * frequence which can change.  In that case, the best choice is
2065 	 * just the preferred erase size.
2066 	 */
2067 	if (mmc_card_mmc(card) && !(card->ext_csd.erase_group_def & 1))
2068 		return card->pref_erase;
2069 
2070 	max_discard = mmc_do_calc_max_discard(card, MMC_ERASE_ARG);
2071 	if (mmc_can_trim(card)) {
2072 		max_trim = mmc_do_calc_max_discard(card, MMC_TRIM_ARG);
2073 		if (max_trim < max_discard || max_discard == 0)
2074 			max_discard = max_trim;
2075 	} else if (max_discard < card->erase_size) {
2076 		max_discard = 0;
2077 	}
2078 	pr_debug("%s: calculated max. discard sectors %u for timeout %u ms\n",
2079 		mmc_hostname(host), max_discard, host->max_busy_timeout ?
2080 		host->max_busy_timeout : MMC_ERASE_TIMEOUT_MS);
2081 	return max_discard;
2082 }
2083 EXPORT_SYMBOL(mmc_calc_max_discard);
2084 
2085 bool mmc_card_is_blockaddr(struct mmc_card *card)
2086 {
2087 	return card ? mmc_card_blockaddr(card) : false;
2088 }
2089 EXPORT_SYMBOL(mmc_card_is_blockaddr);
2090 
2091 int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen)
2092 {
2093 	struct mmc_command cmd = {};
2094 
2095 	if (mmc_card_blockaddr(card) || mmc_card_ddr52(card) ||
2096 	    mmc_card_hs400(card) || mmc_card_hs400es(card))
2097 		return 0;
2098 
2099 	cmd.opcode = MMC_SET_BLOCKLEN;
2100 	cmd.arg = blocklen;
2101 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
2102 	return mmc_wait_for_cmd(card->host, &cmd, 5);
2103 }
2104 EXPORT_SYMBOL(mmc_set_blocklen);
2105 
2106 static void mmc_hw_reset_for_init(struct mmc_host *host)
2107 {
2108 	mmc_pwrseq_reset(host);
2109 
2110 	if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
2111 		return;
2112 	host->ops->hw_reset(host);
2113 }
2114 
2115 int mmc_hw_reset(struct mmc_host *host)
2116 {
2117 	int ret;
2118 
2119 	if (!host->card)
2120 		return -EINVAL;
2121 
2122 	mmc_bus_get(host);
2123 	if (!host->bus_ops || host->bus_dead || !host->bus_ops->hw_reset) {
2124 		mmc_bus_put(host);
2125 		return -EOPNOTSUPP;
2126 	}
2127 
2128 	ret = host->bus_ops->hw_reset(host);
2129 	mmc_bus_put(host);
2130 
2131 	if (ret < 0)
2132 		pr_warn("%s: tried to HW reset card, got error %d\n",
2133 			mmc_hostname(host), ret);
2134 
2135 	return ret;
2136 }
2137 EXPORT_SYMBOL(mmc_hw_reset);
2138 
2139 int mmc_sw_reset(struct mmc_host *host)
2140 {
2141 	int ret;
2142 
2143 	if (!host->card)
2144 		return -EINVAL;
2145 
2146 	mmc_bus_get(host);
2147 	if (!host->bus_ops || host->bus_dead || !host->bus_ops->sw_reset) {
2148 		mmc_bus_put(host);
2149 		return -EOPNOTSUPP;
2150 	}
2151 
2152 	ret = host->bus_ops->sw_reset(host);
2153 	mmc_bus_put(host);
2154 
2155 	if (ret)
2156 		pr_warn("%s: tried to SW reset card, got error %d\n",
2157 			mmc_hostname(host), ret);
2158 
2159 	return ret;
2160 }
2161 EXPORT_SYMBOL(mmc_sw_reset);
2162 
2163 static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
2164 {
2165 	host->f_init = freq;
2166 
2167 	pr_debug("%s: %s: trying to init card at %u Hz\n",
2168 		mmc_hostname(host), __func__, host->f_init);
2169 
2170 	mmc_power_up(host, host->ocr_avail);
2171 
2172 	/*
2173 	 * Some eMMCs (with VCCQ always on) may not be reset after power up, so
2174 	 * do a hardware reset if possible.
2175 	 */
2176 	mmc_hw_reset_for_init(host);
2177 
2178 	/*
2179 	 * sdio_reset sends CMD52 to reset card.  Since we do not know
2180 	 * if the card is being re-initialized, just send it.  CMD52
2181 	 * should be ignored by SD/eMMC cards.
2182 	 * Skip it if we already know that we do not support SDIO commands
2183 	 */
2184 	if (!(host->caps2 & MMC_CAP2_NO_SDIO))
2185 		sdio_reset(host);
2186 
2187 	mmc_go_idle(host);
2188 
2189 	if (!(host->caps2 & MMC_CAP2_NO_SD))
2190 		mmc_send_if_cond(host, host->ocr_avail);
2191 
2192 	/* Order's important: probe SDIO, then SD, then MMC */
2193 	if (!(host->caps2 & MMC_CAP2_NO_SDIO))
2194 		if (!mmc_attach_sdio(host))
2195 			return 0;
2196 
2197 	if (!(host->caps2 & MMC_CAP2_NO_SD))
2198 		if (!mmc_attach_sd(host))
2199 			return 0;
2200 
2201 	if (!(host->caps2 & MMC_CAP2_NO_MMC))
2202 		if (!mmc_attach_mmc(host))
2203 			return 0;
2204 
2205 	mmc_power_off(host);
2206 	return -EIO;
2207 }
2208 
2209 int _mmc_detect_card_removed(struct mmc_host *host)
2210 {
2211 	int ret;
2212 
2213 	if (!host->card || mmc_card_removed(host->card))
2214 		return 1;
2215 
2216 	ret = host->bus_ops->alive(host);
2217 
2218 	/*
2219 	 * Card detect status and alive check may be out of sync if card is
2220 	 * removed slowly, when card detect switch changes while card/slot
2221 	 * pads are still contacted in hardware (refer to "SD Card Mechanical
2222 	 * Addendum, Appendix C: Card Detection Switch"). So reschedule a
2223 	 * detect work 200ms later for this case.
2224 	 */
2225 	if (!ret && host->ops->get_cd && !host->ops->get_cd(host)) {
2226 		mmc_detect_change(host, msecs_to_jiffies(200));
2227 		pr_debug("%s: card removed too slowly\n", mmc_hostname(host));
2228 	}
2229 
2230 	if (ret) {
2231 		mmc_card_set_removed(host->card);
2232 		pr_debug("%s: card remove detected\n", mmc_hostname(host));
2233 	}
2234 
2235 	return ret;
2236 }
2237 
2238 int mmc_detect_card_removed(struct mmc_host *host)
2239 {
2240 	struct mmc_card *card = host->card;
2241 	int ret;
2242 
2243 	WARN_ON(!host->claimed);
2244 
2245 	if (!card)
2246 		return 1;
2247 
2248 	if (!mmc_card_is_removable(host))
2249 		return 0;
2250 
2251 	ret = mmc_card_removed(card);
2252 	/*
2253 	 * The card will be considered unchanged unless we have been asked to
2254 	 * detect a change or host requires polling to provide card detection.
2255 	 */
2256 	if (!host->detect_change && !(host->caps & MMC_CAP_NEEDS_POLL))
2257 		return ret;
2258 
2259 	host->detect_change = 0;
2260 	if (!ret) {
2261 		ret = _mmc_detect_card_removed(host);
2262 		if (ret && (host->caps & MMC_CAP_NEEDS_POLL)) {
2263 			/*
2264 			 * Schedule a detect work as soon as possible to let a
2265 			 * rescan handle the card removal.
2266 			 */
2267 			cancel_delayed_work(&host->detect);
2268 			_mmc_detect_change(host, 0, false);
2269 		}
2270 	}
2271 
2272 	return ret;
2273 }
2274 EXPORT_SYMBOL(mmc_detect_card_removed);
2275 
2276 void mmc_rescan(struct work_struct *work)
2277 {
2278 	struct mmc_host *host =
2279 		container_of(work, struct mmc_host, detect.work);
2280 	int i;
2281 
2282 	if (host->rescan_disable)
2283 		return;
2284 
2285 	/* If there is a non-removable card registered, only scan once */
2286 	if (!mmc_card_is_removable(host) && host->rescan_entered)
2287 		return;
2288 	host->rescan_entered = 1;
2289 
2290 	if (host->trigger_card_event && host->ops->card_event) {
2291 		mmc_claim_host(host);
2292 		host->ops->card_event(host);
2293 		mmc_release_host(host);
2294 		host->trigger_card_event = false;
2295 	}
2296 
2297 	mmc_bus_get(host);
2298 
2299 	/* Verify a registered card to be functional, else remove it. */
2300 	if (host->bus_ops && !host->bus_dead)
2301 		host->bus_ops->detect(host);
2302 
2303 	host->detect_change = 0;
2304 
2305 	/*
2306 	 * Let mmc_bus_put() free the bus/bus_ops if we've found that
2307 	 * the card is no longer present.
2308 	 */
2309 	mmc_bus_put(host);
2310 	mmc_bus_get(host);
2311 
2312 	/* if there still is a card present, stop here */
2313 	if (host->bus_ops != NULL) {
2314 		mmc_bus_put(host);
2315 		goto out;
2316 	}
2317 
2318 	/*
2319 	 * Only we can add a new handler, so it's safe to
2320 	 * release the lock here.
2321 	 */
2322 	mmc_bus_put(host);
2323 
2324 	mmc_claim_host(host);
2325 	if (mmc_card_is_removable(host) && host->ops->get_cd &&
2326 			host->ops->get_cd(host) == 0) {
2327 		mmc_power_off(host);
2328 		mmc_release_host(host);
2329 		goto out;
2330 	}
2331 
2332 	for (i = 0; i < ARRAY_SIZE(freqs); i++) {
2333 		if (!mmc_rescan_try_freq(host, max(freqs[i], host->f_min)))
2334 			break;
2335 		if (freqs[i] <= host->f_min)
2336 			break;
2337 	}
2338 	mmc_release_host(host);
2339 
2340  out:
2341 	if (host->caps & MMC_CAP_NEEDS_POLL)
2342 		mmc_schedule_delayed_work(&host->detect, HZ);
2343 }
2344 
2345 void mmc_start_host(struct mmc_host *host)
2346 {
2347 	host->f_init = max(freqs[0], host->f_min);
2348 	host->rescan_disable = 0;
2349 	host->ios.power_mode = MMC_POWER_UNDEFINED;
2350 
2351 	if (!(host->caps2 & MMC_CAP2_NO_PRESCAN_POWERUP)) {
2352 		mmc_claim_host(host);
2353 		mmc_power_up(host, host->ocr_avail);
2354 		mmc_release_host(host);
2355 	}
2356 
2357 	mmc_gpiod_request_cd_irq(host);
2358 	_mmc_detect_change(host, 0, false);
2359 }
2360 
2361 void mmc_stop_host(struct mmc_host *host)
2362 {
2363 	if (host->slot.cd_irq >= 0) {
2364 		mmc_gpio_set_cd_wake(host, false);
2365 		disable_irq(host->slot.cd_irq);
2366 	}
2367 
2368 	host->rescan_disable = 1;
2369 	cancel_delayed_work_sync(&host->detect);
2370 
2371 	/* clear pm flags now and let card drivers set them as needed */
2372 	host->pm_flags = 0;
2373 
2374 	mmc_bus_get(host);
2375 	if (host->bus_ops && !host->bus_dead) {
2376 		/* Calling bus_ops->remove() with a claimed host can deadlock */
2377 		host->bus_ops->remove(host);
2378 		mmc_claim_host(host);
2379 		mmc_detach_bus(host);
2380 		mmc_power_off(host);
2381 		mmc_release_host(host);
2382 		mmc_bus_put(host);
2383 		return;
2384 	}
2385 	mmc_bus_put(host);
2386 
2387 	mmc_claim_host(host);
2388 	mmc_power_off(host);
2389 	mmc_release_host(host);
2390 }
2391 
2392 #ifdef CONFIG_PM_SLEEP
2393 /* Do the card removal on suspend if card is assumed removeable
2394  * Do that in pm notifier while userspace isn't yet frozen, so we will be able
2395    to sync the card.
2396 */
2397 static int mmc_pm_notify(struct notifier_block *notify_block,
2398 			unsigned long mode, void *unused)
2399 {
2400 	struct mmc_host *host = container_of(
2401 		notify_block, struct mmc_host, pm_notify);
2402 	unsigned long flags;
2403 	int err = 0;
2404 
2405 	switch (mode) {
2406 	case PM_HIBERNATION_PREPARE:
2407 	case PM_SUSPEND_PREPARE:
2408 	case PM_RESTORE_PREPARE:
2409 		spin_lock_irqsave(&host->lock, flags);
2410 		host->rescan_disable = 1;
2411 		spin_unlock_irqrestore(&host->lock, flags);
2412 		cancel_delayed_work_sync(&host->detect);
2413 
2414 		if (!host->bus_ops)
2415 			break;
2416 
2417 		/* Validate prerequisites for suspend */
2418 		if (host->bus_ops->pre_suspend)
2419 			err = host->bus_ops->pre_suspend(host);
2420 		if (!err)
2421 			break;
2422 
2423 		if (!mmc_card_is_removable(host)) {
2424 			dev_warn(mmc_dev(host),
2425 				 "pre_suspend failed for non-removable host: "
2426 				 "%d\n", err);
2427 			/* Avoid removing non-removable hosts */
2428 			break;
2429 		}
2430 
2431 		/* Calling bus_ops->remove() with a claimed host can deadlock */
2432 		host->bus_ops->remove(host);
2433 		mmc_claim_host(host);
2434 		mmc_detach_bus(host);
2435 		mmc_power_off(host);
2436 		mmc_release_host(host);
2437 		host->pm_flags = 0;
2438 		break;
2439 
2440 	case PM_POST_SUSPEND:
2441 	case PM_POST_HIBERNATION:
2442 	case PM_POST_RESTORE:
2443 
2444 		spin_lock_irqsave(&host->lock, flags);
2445 		host->rescan_disable = 0;
2446 		spin_unlock_irqrestore(&host->lock, flags);
2447 		_mmc_detect_change(host, 0, false);
2448 
2449 	}
2450 
2451 	return 0;
2452 }
2453 
2454 void mmc_register_pm_notifier(struct mmc_host *host)
2455 {
2456 	host->pm_notify.notifier_call = mmc_pm_notify;
2457 	register_pm_notifier(&host->pm_notify);
2458 }
2459 
2460 void mmc_unregister_pm_notifier(struct mmc_host *host)
2461 {
2462 	unregister_pm_notifier(&host->pm_notify);
2463 }
2464 #endif
2465 
2466 static int __init mmc_init(void)
2467 {
2468 	int ret;
2469 
2470 	ret = mmc_register_bus();
2471 	if (ret)
2472 		return ret;
2473 
2474 	ret = mmc_register_host_class();
2475 	if (ret)
2476 		goto unregister_bus;
2477 
2478 	ret = sdio_register_bus();
2479 	if (ret)
2480 		goto unregister_host_class;
2481 
2482 	return 0;
2483 
2484 unregister_host_class:
2485 	mmc_unregister_host_class();
2486 unregister_bus:
2487 	mmc_unregister_bus();
2488 	return ret;
2489 }
2490 
2491 static void __exit mmc_exit(void)
2492 {
2493 	sdio_unregister_bus();
2494 	mmc_unregister_host_class();
2495 	mmc_unregister_bus();
2496 }
2497 
2498 subsys_initcall(mmc_init);
2499 module_exit(mmc_exit);
2500 
2501 MODULE_LICENSE("GPL");
2502