xref: /openbmc/linux/drivers/mmc/core/core.c (revision d9f6e12f)
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 		return err;
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  * Cleanup when the last reference to the bus operator is dropped.
1382  */
1383 static void __mmc_release_bus(struct mmc_host *host)
1384 {
1385 	WARN_ON(!host->bus_dead);
1386 
1387 	host->bus_ops = NULL;
1388 }
1389 
1390 /*
1391  * Increase reference count of bus operator
1392  */
1393 static inline void mmc_bus_get(struct mmc_host *host)
1394 {
1395 	unsigned long flags;
1396 
1397 	spin_lock_irqsave(&host->lock, flags);
1398 	host->bus_refs++;
1399 	spin_unlock_irqrestore(&host->lock, flags);
1400 }
1401 
1402 /*
1403  * Decrease reference count of bus operator and free it if
1404  * it is the last reference.
1405  */
1406 static inline void mmc_bus_put(struct mmc_host *host)
1407 {
1408 	unsigned long flags;
1409 
1410 	spin_lock_irqsave(&host->lock, flags);
1411 	host->bus_refs--;
1412 	if ((host->bus_refs == 0) && host->bus_ops)
1413 		__mmc_release_bus(host);
1414 	spin_unlock_irqrestore(&host->lock, flags);
1415 }
1416 
1417 /*
1418  * Assign a mmc bus handler to a host. Only one bus handler may control a
1419  * host at any given time.
1420  */
1421 void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops)
1422 {
1423 	unsigned long flags;
1424 
1425 	WARN_ON(!host->claimed);
1426 
1427 	spin_lock_irqsave(&host->lock, flags);
1428 
1429 	WARN_ON(host->bus_ops);
1430 	WARN_ON(host->bus_refs);
1431 
1432 	host->bus_ops = ops;
1433 	host->bus_refs = 1;
1434 	host->bus_dead = 0;
1435 
1436 	spin_unlock_irqrestore(&host->lock, flags);
1437 }
1438 
1439 /*
1440  * Remove the current bus handler from a host.
1441  */
1442 void mmc_detach_bus(struct mmc_host *host)
1443 {
1444 	unsigned long flags;
1445 
1446 	WARN_ON(!host->claimed);
1447 	WARN_ON(!host->bus_ops);
1448 
1449 	spin_lock_irqsave(&host->lock, flags);
1450 
1451 	host->bus_dead = 1;
1452 
1453 	spin_unlock_irqrestore(&host->lock, flags);
1454 
1455 	mmc_bus_put(host);
1456 }
1457 
1458 void _mmc_detect_change(struct mmc_host *host, unsigned long delay, bool cd_irq)
1459 {
1460 	/*
1461 	 * Prevent system sleep for 5s to allow user space to consume the
1462 	 * corresponding uevent. This is especially useful, when CD irq is used
1463 	 * as a system wakeup, but doesn't hurt in other cases.
1464 	 */
1465 	if (cd_irq && !(host->caps & MMC_CAP_NEEDS_POLL))
1466 		__pm_wakeup_event(host->ws, 5000);
1467 
1468 	host->detect_change = 1;
1469 	mmc_schedule_delayed_work(&host->detect, delay);
1470 }
1471 
1472 /**
1473  *	mmc_detect_change - process change of state on a MMC socket
1474  *	@host: host which changed state.
1475  *	@delay: optional delay to wait before detection (jiffies)
1476  *
1477  *	MMC drivers should call this when they detect a card has been
1478  *	inserted or removed. The MMC layer will confirm that any
1479  *	present card is still functional, and initialize any newly
1480  *	inserted.
1481  */
1482 void mmc_detect_change(struct mmc_host *host, unsigned long delay)
1483 {
1484 	_mmc_detect_change(host, delay, true);
1485 }
1486 EXPORT_SYMBOL(mmc_detect_change);
1487 
1488 void mmc_init_erase(struct mmc_card *card)
1489 {
1490 	unsigned int sz;
1491 
1492 	if (is_power_of_2(card->erase_size))
1493 		card->erase_shift = ffs(card->erase_size) - 1;
1494 	else
1495 		card->erase_shift = 0;
1496 
1497 	/*
1498 	 * It is possible to erase an arbitrarily large area of an SD or MMC
1499 	 * card.  That is not desirable because it can take a long time
1500 	 * (minutes) potentially delaying more important I/O, and also the
1501 	 * timeout calculations become increasingly hugely over-estimated.
1502 	 * Consequently, 'pref_erase' is defined as a guide to limit erases
1503 	 * to that size and alignment.
1504 	 *
1505 	 * For SD cards that define Allocation Unit size, limit erases to one
1506 	 * Allocation Unit at a time.
1507 	 * For MMC, have a stab at ai good value and for modern cards it will
1508 	 * end up being 4MiB. Note that if the value is too small, it can end
1509 	 * up taking longer to erase. Also note, erase_size is already set to
1510 	 * High Capacity Erase Size if available when this function is called.
1511 	 */
1512 	if (mmc_card_sd(card) && card->ssr.au) {
1513 		card->pref_erase = card->ssr.au;
1514 		card->erase_shift = ffs(card->ssr.au) - 1;
1515 	} else if (card->erase_size) {
1516 		sz = (card->csd.capacity << (card->csd.read_blkbits - 9)) >> 11;
1517 		if (sz < 128)
1518 			card->pref_erase = 512 * 1024 / 512;
1519 		else if (sz < 512)
1520 			card->pref_erase = 1024 * 1024 / 512;
1521 		else if (sz < 1024)
1522 			card->pref_erase = 2 * 1024 * 1024 / 512;
1523 		else
1524 			card->pref_erase = 4 * 1024 * 1024 / 512;
1525 		if (card->pref_erase < card->erase_size)
1526 			card->pref_erase = card->erase_size;
1527 		else {
1528 			sz = card->pref_erase % card->erase_size;
1529 			if (sz)
1530 				card->pref_erase += card->erase_size - sz;
1531 		}
1532 	} else
1533 		card->pref_erase = 0;
1534 }
1535 
1536 static unsigned int mmc_mmc_erase_timeout(struct mmc_card *card,
1537 				          unsigned int arg, unsigned int qty)
1538 {
1539 	unsigned int erase_timeout;
1540 
1541 	if (arg == MMC_DISCARD_ARG ||
1542 	    (arg == MMC_TRIM_ARG && card->ext_csd.rev >= 6)) {
1543 		erase_timeout = card->ext_csd.trim_timeout;
1544 	} else if (card->ext_csd.erase_group_def & 1) {
1545 		/* High Capacity Erase Group Size uses HC timeouts */
1546 		if (arg == MMC_TRIM_ARG)
1547 			erase_timeout = card->ext_csd.trim_timeout;
1548 		else
1549 			erase_timeout = card->ext_csd.hc_erase_timeout;
1550 	} else {
1551 		/* CSD Erase Group Size uses write timeout */
1552 		unsigned int mult = (10 << card->csd.r2w_factor);
1553 		unsigned int timeout_clks = card->csd.taac_clks * mult;
1554 		unsigned int timeout_us;
1555 
1556 		/* Avoid overflow: e.g. taac_ns=80000000 mult=1280 */
1557 		if (card->csd.taac_ns < 1000000)
1558 			timeout_us = (card->csd.taac_ns * mult) / 1000;
1559 		else
1560 			timeout_us = (card->csd.taac_ns / 1000) * mult;
1561 
1562 		/*
1563 		 * ios.clock is only a target.  The real clock rate might be
1564 		 * less but not that much less, so fudge it by multiplying by 2.
1565 		 */
1566 		timeout_clks <<= 1;
1567 		timeout_us += (timeout_clks * 1000) /
1568 			      (card->host->ios.clock / 1000);
1569 
1570 		erase_timeout = timeout_us / 1000;
1571 
1572 		/*
1573 		 * Theoretically, the calculation could underflow so round up
1574 		 * to 1ms in that case.
1575 		 */
1576 		if (!erase_timeout)
1577 			erase_timeout = 1;
1578 	}
1579 
1580 	/* Multiplier for secure operations */
1581 	if (arg & MMC_SECURE_ARGS) {
1582 		if (arg == MMC_SECURE_ERASE_ARG)
1583 			erase_timeout *= card->ext_csd.sec_erase_mult;
1584 		else
1585 			erase_timeout *= card->ext_csd.sec_trim_mult;
1586 	}
1587 
1588 	erase_timeout *= qty;
1589 
1590 	/*
1591 	 * Ensure at least a 1 second timeout for SPI as per
1592 	 * 'mmc_set_data_timeout()'
1593 	 */
1594 	if (mmc_host_is_spi(card->host) && erase_timeout < 1000)
1595 		erase_timeout = 1000;
1596 
1597 	return erase_timeout;
1598 }
1599 
1600 static unsigned int mmc_sd_erase_timeout(struct mmc_card *card,
1601 					 unsigned int arg,
1602 					 unsigned int qty)
1603 {
1604 	unsigned int erase_timeout;
1605 
1606 	/* for DISCARD none of the below calculation applies.
1607 	 * the busy timeout is 250msec per discard command.
1608 	 */
1609 	if (arg == SD_DISCARD_ARG)
1610 		return SD_DISCARD_TIMEOUT_MS;
1611 
1612 	if (card->ssr.erase_timeout) {
1613 		/* Erase timeout specified in SD Status Register (SSR) */
1614 		erase_timeout = card->ssr.erase_timeout * qty +
1615 				card->ssr.erase_offset;
1616 	} else {
1617 		/*
1618 		 * Erase timeout not specified in SD Status Register (SSR) so
1619 		 * use 250ms per write block.
1620 		 */
1621 		erase_timeout = 250 * qty;
1622 	}
1623 
1624 	/* Must not be less than 1 second */
1625 	if (erase_timeout < 1000)
1626 		erase_timeout = 1000;
1627 
1628 	return erase_timeout;
1629 }
1630 
1631 static unsigned int mmc_erase_timeout(struct mmc_card *card,
1632 				      unsigned int arg,
1633 				      unsigned int qty)
1634 {
1635 	if (mmc_card_sd(card))
1636 		return mmc_sd_erase_timeout(card, arg, qty);
1637 	else
1638 		return mmc_mmc_erase_timeout(card, arg, qty);
1639 }
1640 
1641 static int mmc_do_erase(struct mmc_card *card, unsigned int from,
1642 			unsigned int to, unsigned int arg)
1643 {
1644 	struct mmc_command cmd = {};
1645 	unsigned int qty = 0, busy_timeout = 0;
1646 	bool use_r1b_resp = false;
1647 	int err;
1648 
1649 	mmc_retune_hold(card->host);
1650 
1651 	/*
1652 	 * qty is used to calculate the erase timeout which depends on how many
1653 	 * erase groups (or allocation units in SD terminology) are affected.
1654 	 * We count erasing part of an erase group as one erase group.
1655 	 * For SD, the allocation units are always a power of 2.  For MMC, the
1656 	 * erase group size is almost certainly also power of 2, but it does not
1657 	 * seem to insist on that in the JEDEC standard, so we fall back to
1658 	 * division in that case.  SD may not specify an allocation unit size,
1659 	 * in which case the timeout is based on the number of write blocks.
1660 	 *
1661 	 * Note that the timeout for secure trim 2 will only be correct if the
1662 	 * number of erase groups specified is the same as the total of all
1663 	 * preceding secure trim 1 commands.  Since the power may have been
1664 	 * lost since the secure trim 1 commands occurred, it is generally
1665 	 * impossible to calculate the secure trim 2 timeout correctly.
1666 	 */
1667 	if (card->erase_shift)
1668 		qty += ((to >> card->erase_shift) -
1669 			(from >> card->erase_shift)) + 1;
1670 	else if (mmc_card_sd(card))
1671 		qty += to - from + 1;
1672 	else
1673 		qty += ((to / card->erase_size) -
1674 			(from / card->erase_size)) + 1;
1675 
1676 	if (!mmc_card_blockaddr(card)) {
1677 		from <<= 9;
1678 		to <<= 9;
1679 	}
1680 
1681 	if (mmc_card_sd(card))
1682 		cmd.opcode = SD_ERASE_WR_BLK_START;
1683 	else
1684 		cmd.opcode = MMC_ERASE_GROUP_START;
1685 	cmd.arg = from;
1686 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
1687 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
1688 	if (err) {
1689 		pr_err("mmc_erase: group start error %d, "
1690 		       "status %#x\n", err, cmd.resp[0]);
1691 		err = -EIO;
1692 		goto out;
1693 	}
1694 
1695 	memset(&cmd, 0, sizeof(struct mmc_command));
1696 	if (mmc_card_sd(card))
1697 		cmd.opcode = SD_ERASE_WR_BLK_END;
1698 	else
1699 		cmd.opcode = MMC_ERASE_GROUP_END;
1700 	cmd.arg = to;
1701 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
1702 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
1703 	if (err) {
1704 		pr_err("mmc_erase: group end error %d, status %#x\n",
1705 		       err, cmd.resp[0]);
1706 		err = -EIO;
1707 		goto out;
1708 	}
1709 
1710 	memset(&cmd, 0, sizeof(struct mmc_command));
1711 	cmd.opcode = MMC_ERASE;
1712 	cmd.arg = arg;
1713 	busy_timeout = mmc_erase_timeout(card, arg, qty);
1714 	/*
1715 	 * If the host controller supports busy signalling and the timeout for
1716 	 * the erase operation does not exceed the max_busy_timeout, we should
1717 	 * use R1B response. Or we need to prevent the host from doing hw busy
1718 	 * detection, which is done by converting to a R1 response instead.
1719 	 * Note, some hosts requires R1B, which also means they are on their own
1720 	 * when it comes to deal with the busy timeout.
1721 	 */
1722 	if (!(card->host->caps & MMC_CAP_NEED_RSP_BUSY) &&
1723 	    card->host->max_busy_timeout &&
1724 	    busy_timeout > card->host->max_busy_timeout) {
1725 		cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
1726 	} else {
1727 		cmd.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
1728 		cmd.busy_timeout = busy_timeout;
1729 		use_r1b_resp = true;
1730 	}
1731 
1732 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
1733 	if (err) {
1734 		pr_err("mmc_erase: erase error %d, status %#x\n",
1735 		       err, cmd.resp[0]);
1736 		err = -EIO;
1737 		goto out;
1738 	}
1739 
1740 	if (mmc_host_is_spi(card->host))
1741 		goto out;
1742 
1743 	/*
1744 	 * In case of when R1B + MMC_CAP_WAIT_WHILE_BUSY is used, the polling
1745 	 * shall be avoided.
1746 	 */
1747 	if ((card->host->caps & MMC_CAP_WAIT_WHILE_BUSY) && use_r1b_resp)
1748 		goto out;
1749 
1750 	/* Let's poll to find out when the erase operation completes. */
1751 	err = mmc_poll_for_busy(card, busy_timeout, MMC_BUSY_ERASE);
1752 
1753 out:
1754 	mmc_retune_release(card->host);
1755 	return err;
1756 }
1757 
1758 static unsigned int mmc_align_erase_size(struct mmc_card *card,
1759 					 unsigned int *from,
1760 					 unsigned int *to,
1761 					 unsigned int nr)
1762 {
1763 	unsigned int from_new = *from, nr_new = nr, rem;
1764 
1765 	/*
1766 	 * When the 'card->erase_size' is power of 2, we can use round_up/down()
1767 	 * to align the erase size efficiently.
1768 	 */
1769 	if (is_power_of_2(card->erase_size)) {
1770 		unsigned int temp = from_new;
1771 
1772 		from_new = round_up(temp, card->erase_size);
1773 		rem = from_new - temp;
1774 
1775 		if (nr_new > rem)
1776 			nr_new -= rem;
1777 		else
1778 			return 0;
1779 
1780 		nr_new = round_down(nr_new, card->erase_size);
1781 	} else {
1782 		rem = from_new % card->erase_size;
1783 		if (rem) {
1784 			rem = card->erase_size - rem;
1785 			from_new += rem;
1786 			if (nr_new > rem)
1787 				nr_new -= rem;
1788 			else
1789 				return 0;
1790 		}
1791 
1792 		rem = nr_new % card->erase_size;
1793 		if (rem)
1794 			nr_new -= rem;
1795 	}
1796 
1797 	if (nr_new == 0)
1798 		return 0;
1799 
1800 	*to = from_new + nr_new;
1801 	*from = from_new;
1802 
1803 	return nr_new;
1804 }
1805 
1806 /**
1807  * mmc_erase - erase sectors.
1808  * @card: card to erase
1809  * @from: first sector to erase
1810  * @nr: number of sectors to erase
1811  * @arg: erase command argument
1812  *
1813  * Caller must claim host before calling this function.
1814  */
1815 int mmc_erase(struct mmc_card *card, unsigned int from, unsigned int nr,
1816 	      unsigned int arg)
1817 {
1818 	unsigned int rem, to = from + nr;
1819 	int err;
1820 
1821 	if (!(card->csd.cmdclass & CCC_ERASE))
1822 		return -EOPNOTSUPP;
1823 
1824 	if (!card->erase_size)
1825 		return -EOPNOTSUPP;
1826 
1827 	if (mmc_card_sd(card) && arg != SD_ERASE_ARG && arg != SD_DISCARD_ARG)
1828 		return -EOPNOTSUPP;
1829 
1830 	if (mmc_card_mmc(card) && (arg & MMC_SECURE_ARGS) &&
1831 	    !(card->ext_csd.sec_feature_support & EXT_CSD_SEC_ER_EN))
1832 		return -EOPNOTSUPP;
1833 
1834 	if (mmc_card_mmc(card) && (arg & MMC_TRIM_ARGS) &&
1835 	    !(card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN))
1836 		return -EOPNOTSUPP;
1837 
1838 	if (arg == MMC_SECURE_ERASE_ARG) {
1839 		if (from % card->erase_size || nr % card->erase_size)
1840 			return -EINVAL;
1841 	}
1842 
1843 	if (arg == MMC_ERASE_ARG)
1844 		nr = mmc_align_erase_size(card, &from, &to, nr);
1845 
1846 	if (nr == 0)
1847 		return 0;
1848 
1849 	if (to <= from)
1850 		return -EINVAL;
1851 
1852 	/* 'from' and 'to' are inclusive */
1853 	to -= 1;
1854 
1855 	/*
1856 	 * Special case where only one erase-group fits in the timeout budget:
1857 	 * If the region crosses an erase-group boundary on this particular
1858 	 * case, we will be trimming more than one erase-group which, does not
1859 	 * fit in the timeout budget of the controller, so we need to split it
1860 	 * and call mmc_do_erase() twice if necessary. This special case is
1861 	 * identified by the card->eg_boundary flag.
1862 	 */
1863 	rem = card->erase_size - (from % card->erase_size);
1864 	if ((arg & MMC_TRIM_ARGS) && (card->eg_boundary) && (nr > rem)) {
1865 		err = mmc_do_erase(card, from, from + rem - 1, arg);
1866 		from += rem;
1867 		if ((err) || (to <= from))
1868 			return err;
1869 	}
1870 
1871 	return mmc_do_erase(card, from, to, arg);
1872 }
1873 EXPORT_SYMBOL(mmc_erase);
1874 
1875 int mmc_can_erase(struct mmc_card *card)
1876 {
1877 	if (card->csd.cmdclass & CCC_ERASE && card->erase_size)
1878 		return 1;
1879 	return 0;
1880 }
1881 EXPORT_SYMBOL(mmc_can_erase);
1882 
1883 int mmc_can_trim(struct mmc_card *card)
1884 {
1885 	if ((card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN) &&
1886 	    (!(card->quirks & MMC_QUIRK_TRIM_BROKEN)))
1887 		return 1;
1888 	return 0;
1889 }
1890 EXPORT_SYMBOL(mmc_can_trim);
1891 
1892 int mmc_can_discard(struct mmc_card *card)
1893 {
1894 	/*
1895 	 * As there's no way to detect the discard support bit at v4.5
1896 	 * use the s/w feature support filed.
1897 	 */
1898 	if (card->ext_csd.feature_support & MMC_DISCARD_FEATURE)
1899 		return 1;
1900 	return 0;
1901 }
1902 EXPORT_SYMBOL(mmc_can_discard);
1903 
1904 int mmc_can_sanitize(struct mmc_card *card)
1905 {
1906 	if (!mmc_can_trim(card) && !mmc_can_erase(card))
1907 		return 0;
1908 	if (card->ext_csd.sec_feature_support & EXT_CSD_SEC_SANITIZE)
1909 		return 1;
1910 	return 0;
1911 }
1912 
1913 int mmc_can_secure_erase_trim(struct mmc_card *card)
1914 {
1915 	if ((card->ext_csd.sec_feature_support & EXT_CSD_SEC_ER_EN) &&
1916 	    !(card->quirks & MMC_QUIRK_SEC_ERASE_TRIM_BROKEN))
1917 		return 1;
1918 	return 0;
1919 }
1920 EXPORT_SYMBOL(mmc_can_secure_erase_trim);
1921 
1922 int mmc_erase_group_aligned(struct mmc_card *card, unsigned int from,
1923 			    unsigned int nr)
1924 {
1925 	if (!card->erase_size)
1926 		return 0;
1927 	if (from % card->erase_size || nr % card->erase_size)
1928 		return 0;
1929 	return 1;
1930 }
1931 EXPORT_SYMBOL(mmc_erase_group_aligned);
1932 
1933 static unsigned int mmc_do_calc_max_discard(struct mmc_card *card,
1934 					    unsigned int arg)
1935 {
1936 	struct mmc_host *host = card->host;
1937 	unsigned int max_discard, x, y, qty = 0, max_qty, min_qty, timeout;
1938 	unsigned int last_timeout = 0;
1939 	unsigned int max_busy_timeout = host->max_busy_timeout ?
1940 			host->max_busy_timeout : MMC_ERASE_TIMEOUT_MS;
1941 
1942 	if (card->erase_shift) {
1943 		max_qty = UINT_MAX >> card->erase_shift;
1944 		min_qty = card->pref_erase >> card->erase_shift;
1945 	} else if (mmc_card_sd(card)) {
1946 		max_qty = UINT_MAX;
1947 		min_qty = card->pref_erase;
1948 	} else {
1949 		max_qty = UINT_MAX / card->erase_size;
1950 		min_qty = card->pref_erase / card->erase_size;
1951 	}
1952 
1953 	/*
1954 	 * We should not only use 'host->max_busy_timeout' as the limitation
1955 	 * when deciding the max discard sectors. We should set a balance value
1956 	 * to improve the erase speed, and it can not get too long timeout at
1957 	 * the same time.
1958 	 *
1959 	 * Here we set 'card->pref_erase' as the minimal discard sectors no
1960 	 * matter what size of 'host->max_busy_timeout', but if the
1961 	 * 'host->max_busy_timeout' is large enough for more discard sectors,
1962 	 * then we can continue to increase the max discard sectors until we
1963 	 * get a balance value. In cases when the 'host->max_busy_timeout'
1964 	 * isn't specified, use the default max erase timeout.
1965 	 */
1966 	do {
1967 		y = 0;
1968 		for (x = 1; x && x <= max_qty && max_qty - x >= qty; x <<= 1) {
1969 			timeout = mmc_erase_timeout(card, arg, qty + x);
1970 
1971 			if (qty + x > min_qty && timeout > max_busy_timeout)
1972 				break;
1973 
1974 			if (timeout < last_timeout)
1975 				break;
1976 			last_timeout = timeout;
1977 			y = x;
1978 		}
1979 		qty += y;
1980 	} while (y);
1981 
1982 	if (!qty)
1983 		return 0;
1984 
1985 	/*
1986 	 * When specifying a sector range to trim, chances are we might cross
1987 	 * an erase-group boundary even if the amount of sectors is less than
1988 	 * one erase-group.
1989 	 * If we can only fit one erase-group in the controller timeout budget,
1990 	 * we have to care that erase-group boundaries are not crossed by a
1991 	 * single trim operation. We flag that special case with "eg_boundary".
1992 	 * In all other cases we can just decrement qty and pretend that we
1993 	 * always touch (qty + 1) erase-groups as a simple optimization.
1994 	 */
1995 	if (qty == 1)
1996 		card->eg_boundary = 1;
1997 	else
1998 		qty--;
1999 
2000 	/* Convert qty to sectors */
2001 	if (card->erase_shift)
2002 		max_discard = qty << card->erase_shift;
2003 	else if (mmc_card_sd(card))
2004 		max_discard = qty + 1;
2005 	else
2006 		max_discard = qty * card->erase_size;
2007 
2008 	return max_discard;
2009 }
2010 
2011 unsigned int mmc_calc_max_discard(struct mmc_card *card)
2012 {
2013 	struct mmc_host *host = card->host;
2014 	unsigned int max_discard, max_trim;
2015 
2016 	/*
2017 	 * Without erase_group_def set, MMC erase timeout depends on clock
2018 	 * frequence which can change.  In that case, the best choice is
2019 	 * just the preferred erase size.
2020 	 */
2021 	if (mmc_card_mmc(card) && !(card->ext_csd.erase_group_def & 1))
2022 		return card->pref_erase;
2023 
2024 	max_discard = mmc_do_calc_max_discard(card, MMC_ERASE_ARG);
2025 	if (mmc_can_trim(card)) {
2026 		max_trim = mmc_do_calc_max_discard(card, MMC_TRIM_ARG);
2027 		if (max_trim < max_discard || max_discard == 0)
2028 			max_discard = max_trim;
2029 	} else if (max_discard < card->erase_size) {
2030 		max_discard = 0;
2031 	}
2032 	pr_debug("%s: calculated max. discard sectors %u for timeout %u ms\n",
2033 		mmc_hostname(host), max_discard, host->max_busy_timeout ?
2034 		host->max_busy_timeout : MMC_ERASE_TIMEOUT_MS);
2035 	return max_discard;
2036 }
2037 EXPORT_SYMBOL(mmc_calc_max_discard);
2038 
2039 bool mmc_card_is_blockaddr(struct mmc_card *card)
2040 {
2041 	return card ? mmc_card_blockaddr(card) : false;
2042 }
2043 EXPORT_SYMBOL(mmc_card_is_blockaddr);
2044 
2045 int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen)
2046 {
2047 	struct mmc_command cmd = {};
2048 
2049 	if (mmc_card_blockaddr(card) || mmc_card_ddr52(card) ||
2050 	    mmc_card_hs400(card) || mmc_card_hs400es(card))
2051 		return 0;
2052 
2053 	cmd.opcode = MMC_SET_BLOCKLEN;
2054 	cmd.arg = blocklen;
2055 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
2056 	return mmc_wait_for_cmd(card->host, &cmd, 5);
2057 }
2058 EXPORT_SYMBOL(mmc_set_blocklen);
2059 
2060 static void mmc_hw_reset_for_init(struct mmc_host *host)
2061 {
2062 	mmc_pwrseq_reset(host);
2063 
2064 	if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
2065 		return;
2066 	host->ops->hw_reset(host);
2067 }
2068 
2069 /**
2070  * mmc_hw_reset - reset the card in hardware
2071  * @host: MMC host to which the card is attached
2072  *
2073  * Hard reset the card. This function is only for upper layers, like the
2074  * block layer or card drivers. You cannot use it in host drivers (struct
2075  * mmc_card might be gone then).
2076  *
2077  * Return: 0 on success, -errno on failure
2078  */
2079 int mmc_hw_reset(struct mmc_host *host)
2080 {
2081 	int ret;
2082 
2083 	if (!host->card)
2084 		return -EINVAL;
2085 
2086 	mmc_bus_get(host);
2087 	if (!host->bus_ops || host->bus_dead || !host->bus_ops->hw_reset) {
2088 		mmc_bus_put(host);
2089 		return -EOPNOTSUPP;
2090 	}
2091 
2092 	ret = host->bus_ops->hw_reset(host);
2093 	mmc_bus_put(host);
2094 
2095 	if (ret < 0)
2096 		pr_warn("%s: tried to HW reset card, got error %d\n",
2097 			mmc_hostname(host), ret);
2098 
2099 	return ret;
2100 }
2101 EXPORT_SYMBOL(mmc_hw_reset);
2102 
2103 int mmc_sw_reset(struct mmc_host *host)
2104 {
2105 	int ret;
2106 
2107 	if (!host->card)
2108 		return -EINVAL;
2109 
2110 	mmc_bus_get(host);
2111 	if (!host->bus_ops || host->bus_dead || !host->bus_ops->sw_reset) {
2112 		mmc_bus_put(host);
2113 		return -EOPNOTSUPP;
2114 	}
2115 
2116 	ret = host->bus_ops->sw_reset(host);
2117 	mmc_bus_put(host);
2118 
2119 	if (ret)
2120 		pr_warn("%s: tried to SW reset card, got error %d\n",
2121 			mmc_hostname(host), ret);
2122 
2123 	return ret;
2124 }
2125 EXPORT_SYMBOL(mmc_sw_reset);
2126 
2127 static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
2128 {
2129 	host->f_init = freq;
2130 
2131 	pr_debug("%s: %s: trying to init card at %u Hz\n",
2132 		mmc_hostname(host), __func__, host->f_init);
2133 
2134 	mmc_power_up(host, host->ocr_avail);
2135 
2136 	/*
2137 	 * Some eMMCs (with VCCQ always on) may not be reset after power up, so
2138 	 * do a hardware reset if possible.
2139 	 */
2140 	mmc_hw_reset_for_init(host);
2141 
2142 	/*
2143 	 * sdio_reset sends CMD52 to reset card.  Since we do not know
2144 	 * if the card is being re-initialized, just send it.  CMD52
2145 	 * should be ignored by SD/eMMC cards.
2146 	 * Skip it if we already know that we do not support SDIO commands
2147 	 */
2148 	if (!(host->caps2 & MMC_CAP2_NO_SDIO))
2149 		sdio_reset(host);
2150 
2151 	mmc_go_idle(host);
2152 
2153 	if (!(host->caps2 & MMC_CAP2_NO_SD)) {
2154 		if (mmc_send_if_cond_pcie(host, host->ocr_avail))
2155 			goto out;
2156 		if (mmc_card_sd_express(host))
2157 			return 0;
2158 	}
2159 
2160 	/* Order's important: probe SDIO, then SD, then MMC */
2161 	if (!(host->caps2 & MMC_CAP2_NO_SDIO))
2162 		if (!mmc_attach_sdio(host))
2163 			return 0;
2164 
2165 	if (!(host->caps2 & MMC_CAP2_NO_SD))
2166 		if (!mmc_attach_sd(host))
2167 			return 0;
2168 
2169 	if (!(host->caps2 & MMC_CAP2_NO_MMC))
2170 		if (!mmc_attach_mmc(host))
2171 			return 0;
2172 
2173 out:
2174 	mmc_power_off(host);
2175 	return -EIO;
2176 }
2177 
2178 int _mmc_detect_card_removed(struct mmc_host *host)
2179 {
2180 	int ret;
2181 
2182 	if (!host->card || mmc_card_removed(host->card))
2183 		return 1;
2184 
2185 	ret = host->bus_ops->alive(host);
2186 
2187 	/*
2188 	 * Card detect status and alive check may be out of sync if card is
2189 	 * removed slowly, when card detect switch changes while card/slot
2190 	 * pads are still contacted in hardware (refer to "SD Card Mechanical
2191 	 * Addendum, Appendix C: Card Detection Switch"). So reschedule a
2192 	 * detect work 200ms later for this case.
2193 	 */
2194 	if (!ret && host->ops->get_cd && !host->ops->get_cd(host)) {
2195 		mmc_detect_change(host, msecs_to_jiffies(200));
2196 		pr_debug("%s: card removed too slowly\n", mmc_hostname(host));
2197 	}
2198 
2199 	if (ret) {
2200 		mmc_card_set_removed(host->card);
2201 		pr_debug("%s: card remove detected\n", mmc_hostname(host));
2202 	}
2203 
2204 	return ret;
2205 }
2206 
2207 int mmc_detect_card_removed(struct mmc_host *host)
2208 {
2209 	struct mmc_card *card = host->card;
2210 	int ret;
2211 
2212 	WARN_ON(!host->claimed);
2213 
2214 	if (!card)
2215 		return 1;
2216 
2217 	if (!mmc_card_is_removable(host))
2218 		return 0;
2219 
2220 	ret = mmc_card_removed(card);
2221 	/*
2222 	 * The card will be considered unchanged unless we have been asked to
2223 	 * detect a change or host requires polling to provide card detection.
2224 	 */
2225 	if (!host->detect_change && !(host->caps & MMC_CAP_NEEDS_POLL))
2226 		return ret;
2227 
2228 	host->detect_change = 0;
2229 	if (!ret) {
2230 		ret = _mmc_detect_card_removed(host);
2231 		if (ret && (host->caps & MMC_CAP_NEEDS_POLL)) {
2232 			/*
2233 			 * Schedule a detect work as soon as possible to let a
2234 			 * rescan handle the card removal.
2235 			 */
2236 			cancel_delayed_work(&host->detect);
2237 			_mmc_detect_change(host, 0, false);
2238 		}
2239 	}
2240 
2241 	return ret;
2242 }
2243 EXPORT_SYMBOL(mmc_detect_card_removed);
2244 
2245 void mmc_rescan(struct work_struct *work)
2246 {
2247 	struct mmc_host *host =
2248 		container_of(work, struct mmc_host, detect.work);
2249 	int i;
2250 
2251 	if (host->rescan_disable)
2252 		return;
2253 
2254 	/* If there is a non-removable card registered, only scan once */
2255 	if (!mmc_card_is_removable(host) && host->rescan_entered)
2256 		return;
2257 	host->rescan_entered = 1;
2258 
2259 	if (host->trigger_card_event && host->ops->card_event) {
2260 		mmc_claim_host(host);
2261 		host->ops->card_event(host);
2262 		mmc_release_host(host);
2263 		host->trigger_card_event = false;
2264 	}
2265 
2266 	mmc_bus_get(host);
2267 
2268 	/* Verify a registered card to be functional, else remove it. */
2269 	if (host->bus_ops && !host->bus_dead)
2270 		host->bus_ops->detect(host);
2271 
2272 	host->detect_change = 0;
2273 
2274 	/*
2275 	 * Let mmc_bus_put() free the bus/bus_ops if we've found that
2276 	 * the card is no longer present.
2277 	 */
2278 	mmc_bus_put(host);
2279 	mmc_bus_get(host);
2280 
2281 	/* if there still is a card present, stop here */
2282 	if (host->bus_ops != NULL) {
2283 		mmc_bus_put(host);
2284 		goto out;
2285 	}
2286 
2287 	/*
2288 	 * Only we can add a new handler, so it's safe to
2289 	 * release the lock here.
2290 	 */
2291 	mmc_bus_put(host);
2292 
2293 	mmc_claim_host(host);
2294 	if (mmc_card_is_removable(host) && host->ops->get_cd &&
2295 			host->ops->get_cd(host) == 0) {
2296 		mmc_power_off(host);
2297 		mmc_release_host(host);
2298 		goto out;
2299 	}
2300 
2301 	/* If an SD express card is present, then leave it as is. */
2302 	if (mmc_card_sd_express(host)) {
2303 		mmc_release_host(host);
2304 		goto out;
2305 	}
2306 
2307 	for (i = 0; i < ARRAY_SIZE(freqs); i++) {
2308 		unsigned int freq = freqs[i];
2309 		if (freq > host->f_max) {
2310 			if (i + 1 < ARRAY_SIZE(freqs))
2311 				continue;
2312 			freq = host->f_max;
2313 		}
2314 		if (!mmc_rescan_try_freq(host, max(freq, host->f_min)))
2315 			break;
2316 		if (freqs[i] <= host->f_min)
2317 			break;
2318 	}
2319 	mmc_release_host(host);
2320 
2321  out:
2322 	if (host->caps & MMC_CAP_NEEDS_POLL)
2323 		mmc_schedule_delayed_work(&host->detect, HZ);
2324 }
2325 
2326 void mmc_start_host(struct mmc_host *host)
2327 {
2328 	host->f_init = max(min(freqs[0], host->f_max), host->f_min);
2329 	host->rescan_disable = 0;
2330 
2331 	if (!(host->caps2 & MMC_CAP2_NO_PRESCAN_POWERUP)) {
2332 		mmc_claim_host(host);
2333 		mmc_power_up(host, host->ocr_avail);
2334 		mmc_release_host(host);
2335 	}
2336 
2337 	mmc_gpiod_request_cd_irq(host);
2338 	_mmc_detect_change(host, 0, false);
2339 }
2340 
2341 void mmc_stop_host(struct mmc_host *host)
2342 {
2343 	if (host->slot.cd_irq >= 0) {
2344 		mmc_gpio_set_cd_wake(host, false);
2345 		disable_irq(host->slot.cd_irq);
2346 	}
2347 
2348 	host->rescan_disable = 1;
2349 	cancel_delayed_work_sync(&host->detect);
2350 
2351 	/* clear pm flags now and let card drivers set them as needed */
2352 	host->pm_flags = 0;
2353 
2354 	mmc_bus_get(host);
2355 	if (host->bus_ops && !host->bus_dead) {
2356 		/* Calling bus_ops->remove() with a claimed host can deadlock */
2357 		host->bus_ops->remove(host);
2358 		mmc_claim_host(host);
2359 		mmc_detach_bus(host);
2360 		mmc_power_off(host);
2361 		mmc_release_host(host);
2362 		mmc_bus_put(host);
2363 		return;
2364 	}
2365 	mmc_bus_put(host);
2366 
2367 	mmc_claim_host(host);
2368 	mmc_power_off(host);
2369 	mmc_release_host(host);
2370 }
2371 
2372 #ifdef CONFIG_PM_SLEEP
2373 /* Do the card removal on suspend if card is assumed removeable
2374  * Do that in pm notifier while userspace isn't yet frozen, so we will be able
2375    to sync the card.
2376 */
2377 static int mmc_pm_notify(struct notifier_block *notify_block,
2378 			unsigned long mode, void *unused)
2379 {
2380 	struct mmc_host *host = container_of(
2381 		notify_block, struct mmc_host, pm_notify);
2382 	unsigned long flags;
2383 	int err = 0;
2384 
2385 	switch (mode) {
2386 	case PM_HIBERNATION_PREPARE:
2387 	case PM_SUSPEND_PREPARE:
2388 	case PM_RESTORE_PREPARE:
2389 		spin_lock_irqsave(&host->lock, flags);
2390 		host->rescan_disable = 1;
2391 		spin_unlock_irqrestore(&host->lock, flags);
2392 		cancel_delayed_work_sync(&host->detect);
2393 
2394 		if (!host->bus_ops)
2395 			break;
2396 
2397 		/* Validate prerequisites for suspend */
2398 		if (host->bus_ops->pre_suspend)
2399 			err = host->bus_ops->pre_suspend(host);
2400 		if (!err)
2401 			break;
2402 
2403 		if (!mmc_card_is_removable(host)) {
2404 			dev_warn(mmc_dev(host),
2405 				 "pre_suspend failed for non-removable host: "
2406 				 "%d\n", err);
2407 			/* Avoid removing non-removable hosts */
2408 			break;
2409 		}
2410 
2411 		/* Calling bus_ops->remove() with a claimed host can deadlock */
2412 		host->bus_ops->remove(host);
2413 		mmc_claim_host(host);
2414 		mmc_detach_bus(host);
2415 		mmc_power_off(host);
2416 		mmc_release_host(host);
2417 		host->pm_flags = 0;
2418 		break;
2419 
2420 	case PM_POST_SUSPEND:
2421 	case PM_POST_HIBERNATION:
2422 	case PM_POST_RESTORE:
2423 
2424 		spin_lock_irqsave(&host->lock, flags);
2425 		host->rescan_disable = 0;
2426 		spin_unlock_irqrestore(&host->lock, flags);
2427 		_mmc_detect_change(host, 0, false);
2428 
2429 	}
2430 
2431 	return 0;
2432 }
2433 
2434 void mmc_register_pm_notifier(struct mmc_host *host)
2435 {
2436 	host->pm_notify.notifier_call = mmc_pm_notify;
2437 	register_pm_notifier(&host->pm_notify);
2438 }
2439 
2440 void mmc_unregister_pm_notifier(struct mmc_host *host)
2441 {
2442 	unregister_pm_notifier(&host->pm_notify);
2443 }
2444 #endif
2445 
2446 static int __init mmc_init(void)
2447 {
2448 	int ret;
2449 
2450 	ret = mmc_register_bus();
2451 	if (ret)
2452 		return ret;
2453 
2454 	ret = mmc_register_host_class();
2455 	if (ret)
2456 		goto unregister_bus;
2457 
2458 	ret = sdio_register_bus();
2459 	if (ret)
2460 		goto unregister_host_class;
2461 
2462 	return 0;
2463 
2464 unregister_host_class:
2465 	mmc_unregister_host_class();
2466 unregister_bus:
2467 	mmc_unregister_bus();
2468 	return ret;
2469 }
2470 
2471 static void __exit mmc_exit(void)
2472 {
2473 	sdio_unregister_bus();
2474 	mmc_unregister_host_class();
2475 	mmc_unregister_bus();
2476 }
2477 
2478 subsys_initcall(mmc_init);
2479 module_exit(mmc_exit);
2480 
2481 MODULE_LICENSE("GPL");
2482