xref: /openbmc/linux/drivers/mmc/core/core.c (revision 1d27a0be)
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 		if (!cmd->error || !cmd->retries ||
407 		    mmc_card_removed(host->card))
408 			break;
409 
410 		mmc_retune_recheck(host);
411 
412 		pr_debug("%s: req failed (CMD%u): %d, retrying...\n",
413 			 mmc_hostname(host), cmd->opcode, cmd->error);
414 		cmd->retries--;
415 		cmd->error = 0;
416 		__mmc_start_request(host, mrq);
417 	}
418 
419 	mmc_retune_release(host);
420 }
421 EXPORT_SYMBOL(mmc_wait_for_req_done);
422 
423 /*
424  * mmc_cqe_start_req - Start a CQE request.
425  * @host: MMC host to start the request
426  * @mrq: request to start
427  *
428  * Start the request, re-tuning if needed and it is possible. Returns an error
429  * code if the request fails to start or -EBUSY if CQE is busy.
430  */
431 int mmc_cqe_start_req(struct mmc_host *host, struct mmc_request *mrq)
432 {
433 	int err;
434 
435 	/*
436 	 * CQE cannot process re-tuning commands. Caller must hold retuning
437 	 * while CQE is in use.  Re-tuning can happen here only when CQE has no
438 	 * active requests i.e. this is the first.  Note, re-tuning will call
439 	 * ->cqe_off().
440 	 */
441 	err = mmc_retune(host);
442 	if (err)
443 		goto out_err;
444 
445 	mrq->host = host;
446 
447 	mmc_mrq_pr_debug(host, mrq, true);
448 
449 	err = mmc_mrq_prep(host, mrq);
450 	if (err)
451 		goto out_err;
452 
453 	err = host->cqe_ops->cqe_request(host, mrq);
454 	if (err)
455 		goto out_err;
456 
457 	trace_mmc_request_start(host, mrq);
458 
459 	return 0;
460 
461 out_err:
462 	if (mrq->cmd) {
463 		pr_debug("%s: failed to start CQE direct CMD%u, error %d\n",
464 			 mmc_hostname(host), mrq->cmd->opcode, err);
465 	} else {
466 		pr_debug("%s: failed to start CQE transfer for tag %d, error %d\n",
467 			 mmc_hostname(host), mrq->tag, err);
468 	}
469 	return err;
470 }
471 EXPORT_SYMBOL(mmc_cqe_start_req);
472 
473 /**
474  *	mmc_cqe_request_done - CQE has finished processing an MMC request
475  *	@host: MMC host which completed request
476  *	@mrq: MMC request which completed
477  *
478  *	CQE drivers should call this function when they have completed
479  *	their processing of a request.
480  */
481 void mmc_cqe_request_done(struct mmc_host *host, struct mmc_request *mrq)
482 {
483 	mmc_should_fail_request(host, mrq);
484 
485 	/* Flag re-tuning needed on CRC errors */
486 	if ((mrq->cmd && mrq->cmd->error == -EILSEQ) ||
487 	    (mrq->data && mrq->data->error == -EILSEQ))
488 		mmc_retune_needed(host);
489 
490 	trace_mmc_request_done(host, mrq);
491 
492 	if (mrq->cmd) {
493 		pr_debug("%s: CQE req done (direct CMD%u): %d\n",
494 			 mmc_hostname(host), mrq->cmd->opcode, mrq->cmd->error);
495 	} else {
496 		pr_debug("%s: CQE transfer done tag %d\n",
497 			 mmc_hostname(host), mrq->tag);
498 	}
499 
500 	if (mrq->data) {
501 		pr_debug("%s:     %d bytes transferred: %d\n",
502 			 mmc_hostname(host),
503 			 mrq->data->bytes_xfered, mrq->data->error);
504 	}
505 
506 	mrq->done(mrq);
507 }
508 EXPORT_SYMBOL(mmc_cqe_request_done);
509 
510 /**
511  *	mmc_cqe_post_req - CQE post process of a completed MMC request
512  *	@host: MMC host
513  *	@mrq: MMC request to be processed
514  */
515 void mmc_cqe_post_req(struct mmc_host *host, struct mmc_request *mrq)
516 {
517 	if (host->cqe_ops->cqe_post_req)
518 		host->cqe_ops->cqe_post_req(host, mrq);
519 }
520 EXPORT_SYMBOL(mmc_cqe_post_req);
521 
522 /* Arbitrary 1 second timeout */
523 #define MMC_CQE_RECOVERY_TIMEOUT	1000
524 
525 /*
526  * mmc_cqe_recovery - Recover from CQE errors.
527  * @host: MMC host to recover
528  *
529  * Recovery consists of stopping CQE, stopping eMMC, discarding the queue in
530  * in eMMC, and discarding the queue in CQE. CQE must call
531  * mmc_cqe_request_done() on all requests. An error is returned if the eMMC
532  * fails to discard its queue.
533  */
534 int mmc_cqe_recovery(struct mmc_host *host)
535 {
536 	struct mmc_command cmd;
537 	int err;
538 
539 	mmc_retune_hold_now(host);
540 
541 	/*
542 	 * Recovery is expected seldom, if at all, but it reduces performance,
543 	 * so make sure it is not completely silent.
544 	 */
545 	pr_warn("%s: running CQE recovery\n", mmc_hostname(host));
546 
547 	host->cqe_ops->cqe_recovery_start(host);
548 
549 	memset(&cmd, 0, sizeof(cmd));
550 	cmd.opcode       = MMC_STOP_TRANSMISSION,
551 	cmd.flags        = MMC_RSP_R1B | MMC_CMD_AC,
552 	cmd.flags       &= ~MMC_RSP_CRC; /* Ignore CRC */
553 	cmd.busy_timeout = MMC_CQE_RECOVERY_TIMEOUT,
554 	mmc_wait_for_cmd(host, &cmd, 0);
555 
556 	memset(&cmd, 0, sizeof(cmd));
557 	cmd.opcode       = MMC_CMDQ_TASK_MGMT;
558 	cmd.arg          = 1; /* Discard entire queue */
559 	cmd.flags        = MMC_RSP_R1B | MMC_CMD_AC;
560 	cmd.flags       &= ~MMC_RSP_CRC; /* Ignore CRC */
561 	cmd.busy_timeout = MMC_CQE_RECOVERY_TIMEOUT,
562 	err = mmc_wait_for_cmd(host, &cmd, 0);
563 
564 	host->cqe_ops->cqe_recovery_finish(host);
565 
566 	mmc_retune_release(host);
567 
568 	return err;
569 }
570 EXPORT_SYMBOL(mmc_cqe_recovery);
571 
572 /**
573  *	mmc_is_req_done - Determine if a 'cap_cmd_during_tfr' request is done
574  *	@host: MMC host
575  *	@mrq: MMC request
576  *
577  *	mmc_is_req_done() is used with requests that have
578  *	mrq->cap_cmd_during_tfr = true. mmc_is_req_done() must be called after
579  *	starting a request and before waiting for it to complete. That is,
580  *	either in between calls to mmc_start_req(), or after mmc_wait_for_req()
581  *	and before mmc_wait_for_req_done(). If it is called at other times the
582  *	result is not meaningful.
583  */
584 bool mmc_is_req_done(struct mmc_host *host, struct mmc_request *mrq)
585 {
586 	return completion_done(&mrq->completion);
587 }
588 EXPORT_SYMBOL(mmc_is_req_done);
589 
590 /**
591  *	mmc_wait_for_req - start a request and wait for completion
592  *	@host: MMC host to start command
593  *	@mrq: MMC request to start
594  *
595  *	Start a new MMC custom command request for a host, and wait
596  *	for the command to complete. In the case of 'cap_cmd_during_tfr'
597  *	requests, the transfer is ongoing and the caller can issue further
598  *	commands that do not use the data lines, and then wait by calling
599  *	mmc_wait_for_req_done().
600  *	Does not attempt to parse the response.
601  */
602 void mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq)
603 {
604 	__mmc_start_req(host, mrq);
605 
606 	if (!mrq->cap_cmd_during_tfr)
607 		mmc_wait_for_req_done(host, mrq);
608 }
609 EXPORT_SYMBOL(mmc_wait_for_req);
610 
611 /**
612  *	mmc_wait_for_cmd - start a command and wait for completion
613  *	@host: MMC host to start command
614  *	@cmd: MMC command to start
615  *	@retries: maximum number of retries
616  *
617  *	Start a new MMC command for a host, and wait for the command
618  *	to complete.  Return any error that occurred while the command
619  *	was executing.  Do not attempt to parse the response.
620  */
621 int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries)
622 {
623 	struct mmc_request mrq = {};
624 
625 	WARN_ON(!host->claimed);
626 
627 	memset(cmd->resp, 0, sizeof(cmd->resp));
628 	cmd->retries = retries;
629 
630 	mrq.cmd = cmd;
631 	cmd->data = NULL;
632 
633 	mmc_wait_for_req(host, &mrq);
634 
635 	return cmd->error;
636 }
637 
638 EXPORT_SYMBOL(mmc_wait_for_cmd);
639 
640 /**
641  *	mmc_set_data_timeout - set the timeout for a data command
642  *	@data: data phase for command
643  *	@card: the MMC card associated with the data transfer
644  *
645  *	Computes the data timeout parameters according to the
646  *	correct algorithm given the card type.
647  */
648 void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card)
649 {
650 	unsigned int mult;
651 
652 	/*
653 	 * SDIO cards only define an upper 1 s limit on access.
654 	 */
655 	if (mmc_card_sdio(card)) {
656 		data->timeout_ns = 1000000000;
657 		data->timeout_clks = 0;
658 		return;
659 	}
660 
661 	/*
662 	 * SD cards use a 100 multiplier rather than 10
663 	 */
664 	mult = mmc_card_sd(card) ? 100 : 10;
665 
666 	/*
667 	 * Scale up the multiplier (and therefore the timeout) by
668 	 * the r2w factor for writes.
669 	 */
670 	if (data->flags & MMC_DATA_WRITE)
671 		mult <<= card->csd.r2w_factor;
672 
673 	data->timeout_ns = card->csd.taac_ns * mult;
674 	data->timeout_clks = card->csd.taac_clks * mult;
675 
676 	/*
677 	 * SD cards also have an upper limit on the timeout.
678 	 */
679 	if (mmc_card_sd(card)) {
680 		unsigned int timeout_us, limit_us;
681 
682 		timeout_us = data->timeout_ns / 1000;
683 		if (card->host->ios.clock)
684 			timeout_us += data->timeout_clks * 1000 /
685 				(card->host->ios.clock / 1000);
686 
687 		if (data->flags & MMC_DATA_WRITE)
688 			/*
689 			 * The MMC spec "It is strongly recommended
690 			 * for hosts to implement more than 500ms
691 			 * timeout value even if the card indicates
692 			 * the 250ms maximum busy length."  Even the
693 			 * previous value of 300ms is known to be
694 			 * insufficient for some cards.
695 			 */
696 			limit_us = 3000000;
697 		else
698 			limit_us = 100000;
699 
700 		/*
701 		 * SDHC cards always use these fixed values.
702 		 */
703 		if (timeout_us > limit_us) {
704 			data->timeout_ns = limit_us * 1000;
705 			data->timeout_clks = 0;
706 		}
707 
708 		/* assign limit value if invalid */
709 		if (timeout_us == 0)
710 			data->timeout_ns = limit_us * 1000;
711 	}
712 
713 	/*
714 	 * Some cards require longer data read timeout than indicated in CSD.
715 	 * Address this by setting the read timeout to a "reasonably high"
716 	 * value. For the cards tested, 600ms has proven enough. If necessary,
717 	 * this value can be increased if other problematic cards require this.
718 	 */
719 	if (mmc_card_long_read_time(card) && data->flags & MMC_DATA_READ) {
720 		data->timeout_ns = 600000000;
721 		data->timeout_clks = 0;
722 	}
723 
724 	/*
725 	 * Some cards need very high timeouts if driven in SPI mode.
726 	 * The worst observed timeout was 900ms after writing a
727 	 * continuous stream of data until the internal logic
728 	 * overflowed.
729 	 */
730 	if (mmc_host_is_spi(card->host)) {
731 		if (data->flags & MMC_DATA_WRITE) {
732 			if (data->timeout_ns < 1000000000)
733 				data->timeout_ns = 1000000000;	/* 1s */
734 		} else {
735 			if (data->timeout_ns < 100000000)
736 				data->timeout_ns =  100000000;	/* 100ms */
737 		}
738 	}
739 }
740 EXPORT_SYMBOL(mmc_set_data_timeout);
741 
742 /*
743  * Allow claiming an already claimed host if the context is the same or there is
744  * no context but the task is the same.
745  */
746 static inline bool mmc_ctx_matches(struct mmc_host *host, struct mmc_ctx *ctx,
747 				   struct task_struct *task)
748 {
749 	return host->claimer == ctx ||
750 	       (!ctx && task && host->claimer->task == task);
751 }
752 
753 static inline void mmc_ctx_set_claimer(struct mmc_host *host,
754 				       struct mmc_ctx *ctx,
755 				       struct task_struct *task)
756 {
757 	if (!host->claimer) {
758 		if (ctx)
759 			host->claimer = ctx;
760 		else
761 			host->claimer = &host->default_ctx;
762 	}
763 	if (task)
764 		host->claimer->task = task;
765 }
766 
767 /**
768  *	__mmc_claim_host - exclusively claim a host
769  *	@host: mmc host to claim
770  *	@ctx: context that claims the host or NULL in which case the default
771  *	context will be used
772  *	@abort: whether or not the operation should be aborted
773  *
774  *	Claim a host for a set of operations.  If @abort is non null and
775  *	dereference a non-zero value then this will return prematurely with
776  *	that non-zero value without acquiring the lock.  Returns zero
777  *	with the lock held otherwise.
778  */
779 int __mmc_claim_host(struct mmc_host *host, struct mmc_ctx *ctx,
780 		     atomic_t *abort)
781 {
782 	struct task_struct *task = ctx ? NULL : current;
783 	DECLARE_WAITQUEUE(wait, current);
784 	unsigned long flags;
785 	int stop;
786 	bool pm = false;
787 
788 	might_sleep();
789 
790 	add_wait_queue(&host->wq, &wait);
791 	spin_lock_irqsave(&host->lock, flags);
792 	while (1) {
793 		set_current_state(TASK_UNINTERRUPTIBLE);
794 		stop = abort ? atomic_read(abort) : 0;
795 		if (stop || !host->claimed || mmc_ctx_matches(host, ctx, task))
796 			break;
797 		spin_unlock_irqrestore(&host->lock, flags);
798 		schedule();
799 		spin_lock_irqsave(&host->lock, flags);
800 	}
801 	set_current_state(TASK_RUNNING);
802 	if (!stop) {
803 		host->claimed = 1;
804 		mmc_ctx_set_claimer(host, ctx, task);
805 		host->claim_cnt += 1;
806 		if (host->claim_cnt == 1)
807 			pm = true;
808 	} else
809 		wake_up(&host->wq);
810 	spin_unlock_irqrestore(&host->lock, flags);
811 	remove_wait_queue(&host->wq, &wait);
812 
813 	if (pm)
814 		pm_runtime_get_sync(mmc_dev(host));
815 
816 	return stop;
817 }
818 EXPORT_SYMBOL(__mmc_claim_host);
819 
820 /**
821  *	mmc_release_host - release a host
822  *	@host: mmc host to release
823  *
824  *	Release a MMC host, allowing others to claim the host
825  *	for their operations.
826  */
827 void mmc_release_host(struct mmc_host *host)
828 {
829 	unsigned long flags;
830 
831 	WARN_ON(!host->claimed);
832 
833 	spin_lock_irqsave(&host->lock, flags);
834 	if (--host->claim_cnt) {
835 		/* Release for nested claim */
836 		spin_unlock_irqrestore(&host->lock, flags);
837 	} else {
838 		host->claimed = 0;
839 		host->claimer->task = NULL;
840 		host->claimer = NULL;
841 		spin_unlock_irqrestore(&host->lock, flags);
842 		wake_up(&host->wq);
843 		pm_runtime_mark_last_busy(mmc_dev(host));
844 		if (host->caps & MMC_CAP_SYNC_RUNTIME_PM)
845 			pm_runtime_put_sync_suspend(mmc_dev(host));
846 		else
847 			pm_runtime_put_autosuspend(mmc_dev(host));
848 	}
849 }
850 EXPORT_SYMBOL(mmc_release_host);
851 
852 /*
853  * This is a helper function, which fetches a runtime pm reference for the
854  * card device and also claims the host.
855  */
856 void mmc_get_card(struct mmc_card *card, struct mmc_ctx *ctx)
857 {
858 	pm_runtime_get_sync(&card->dev);
859 	__mmc_claim_host(card->host, ctx, NULL);
860 }
861 EXPORT_SYMBOL(mmc_get_card);
862 
863 /*
864  * This is a helper function, which releases the host and drops the runtime
865  * pm reference for the card device.
866  */
867 void mmc_put_card(struct mmc_card *card, struct mmc_ctx *ctx)
868 {
869 	struct mmc_host *host = card->host;
870 
871 	WARN_ON(ctx && host->claimer != ctx);
872 
873 	mmc_release_host(host);
874 	pm_runtime_mark_last_busy(&card->dev);
875 	pm_runtime_put_autosuspend(&card->dev);
876 }
877 EXPORT_SYMBOL(mmc_put_card);
878 
879 /*
880  * Internal function that does the actual ios call to the host driver,
881  * optionally printing some debug output.
882  */
883 static inline void mmc_set_ios(struct mmc_host *host)
884 {
885 	struct mmc_ios *ios = &host->ios;
886 
887 	pr_debug("%s: clock %uHz busmode %u powermode %u cs %u Vdd %u "
888 		"width %u timing %u\n",
889 		 mmc_hostname(host), ios->clock, ios->bus_mode,
890 		 ios->power_mode, ios->chip_select, ios->vdd,
891 		 1 << ios->bus_width, ios->timing);
892 
893 	host->ops->set_ios(host, ios);
894 }
895 
896 /*
897  * Control chip select pin on a host.
898  */
899 void mmc_set_chip_select(struct mmc_host *host, int mode)
900 {
901 	host->ios.chip_select = mode;
902 	mmc_set_ios(host);
903 }
904 
905 /*
906  * Sets the host clock to the highest possible frequency that
907  * is below "hz".
908  */
909 void mmc_set_clock(struct mmc_host *host, unsigned int hz)
910 {
911 	WARN_ON(hz && hz < host->f_min);
912 
913 	if (hz > host->f_max)
914 		hz = host->f_max;
915 
916 	host->ios.clock = hz;
917 	mmc_set_ios(host);
918 }
919 
920 int mmc_execute_tuning(struct mmc_card *card)
921 {
922 	struct mmc_host *host = card->host;
923 	u32 opcode;
924 	int err;
925 
926 	if (!host->ops->execute_tuning)
927 		return 0;
928 
929 	if (host->cqe_on)
930 		host->cqe_ops->cqe_off(host);
931 
932 	if (mmc_card_mmc(card))
933 		opcode = MMC_SEND_TUNING_BLOCK_HS200;
934 	else
935 		opcode = MMC_SEND_TUNING_BLOCK;
936 
937 	err = host->ops->execute_tuning(host, opcode);
938 
939 	if (err)
940 		pr_err("%s: tuning execution failed: %d\n",
941 			mmc_hostname(host), err);
942 	else
943 		mmc_retune_enable(host);
944 
945 	return err;
946 }
947 
948 /*
949  * Change the bus mode (open drain/push-pull) of a host.
950  */
951 void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode)
952 {
953 	host->ios.bus_mode = mode;
954 	mmc_set_ios(host);
955 }
956 
957 /*
958  * Change data bus width of a host.
959  */
960 void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
961 {
962 	host->ios.bus_width = width;
963 	mmc_set_ios(host);
964 }
965 
966 /*
967  * Set initial state after a power cycle or a hw_reset.
968  */
969 void mmc_set_initial_state(struct mmc_host *host)
970 {
971 	if (host->cqe_on)
972 		host->cqe_ops->cqe_off(host);
973 
974 	mmc_retune_disable(host);
975 
976 	if (mmc_host_is_spi(host))
977 		host->ios.chip_select = MMC_CS_HIGH;
978 	else
979 		host->ios.chip_select = MMC_CS_DONTCARE;
980 	host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
981 	host->ios.bus_width = MMC_BUS_WIDTH_1;
982 	host->ios.timing = MMC_TIMING_LEGACY;
983 	host->ios.drv_type = 0;
984 	host->ios.enhanced_strobe = false;
985 
986 	/*
987 	 * Make sure we are in non-enhanced strobe mode before we
988 	 * actually enable it in ext_csd.
989 	 */
990 	if ((host->caps2 & MMC_CAP2_HS400_ES) &&
991 	     host->ops->hs400_enhanced_strobe)
992 		host->ops->hs400_enhanced_strobe(host, &host->ios);
993 
994 	mmc_set_ios(host);
995 }
996 
997 /**
998  * mmc_vdd_to_ocrbitnum - Convert a voltage to the OCR bit number
999  * @vdd:	voltage (mV)
1000  * @low_bits:	prefer low bits in boundary cases
1001  *
1002  * This function returns the OCR bit number according to the provided @vdd
1003  * value. If conversion is not possible a negative errno value returned.
1004  *
1005  * Depending on the @low_bits flag the function prefers low or high OCR bits
1006  * on boundary voltages. For example,
1007  * with @low_bits = true, 3300 mV translates to ilog2(MMC_VDD_32_33);
1008  * with @low_bits = false, 3300 mV translates to ilog2(MMC_VDD_33_34);
1009  *
1010  * Any value in the [1951:1999] range translates to the ilog2(MMC_VDD_20_21).
1011  */
1012 static int mmc_vdd_to_ocrbitnum(int vdd, bool low_bits)
1013 {
1014 	const int max_bit = ilog2(MMC_VDD_35_36);
1015 	int bit;
1016 
1017 	if (vdd < 1650 || vdd > 3600)
1018 		return -EINVAL;
1019 
1020 	if (vdd >= 1650 && vdd <= 1950)
1021 		return ilog2(MMC_VDD_165_195);
1022 
1023 	if (low_bits)
1024 		vdd -= 1;
1025 
1026 	/* Base 2000 mV, step 100 mV, bit's base 8. */
1027 	bit = (vdd - 2000) / 100 + 8;
1028 	if (bit > max_bit)
1029 		return max_bit;
1030 	return bit;
1031 }
1032 
1033 /**
1034  * mmc_vddrange_to_ocrmask - Convert a voltage range to the OCR mask
1035  * @vdd_min:	minimum voltage value (mV)
1036  * @vdd_max:	maximum voltage value (mV)
1037  *
1038  * This function returns the OCR mask bits according to the provided @vdd_min
1039  * and @vdd_max values. If conversion is not possible the function returns 0.
1040  *
1041  * Notes wrt boundary cases:
1042  * This function sets the OCR bits for all boundary voltages, for example
1043  * [3300:3400] range is translated to MMC_VDD_32_33 | MMC_VDD_33_34 |
1044  * MMC_VDD_34_35 mask.
1045  */
1046 u32 mmc_vddrange_to_ocrmask(int vdd_min, int vdd_max)
1047 {
1048 	u32 mask = 0;
1049 
1050 	if (vdd_max < vdd_min)
1051 		return 0;
1052 
1053 	/* Prefer high bits for the boundary vdd_max values. */
1054 	vdd_max = mmc_vdd_to_ocrbitnum(vdd_max, false);
1055 	if (vdd_max < 0)
1056 		return 0;
1057 
1058 	/* Prefer low bits for the boundary vdd_min values. */
1059 	vdd_min = mmc_vdd_to_ocrbitnum(vdd_min, true);
1060 	if (vdd_min < 0)
1061 		return 0;
1062 
1063 	/* Fill the mask, from max bit to min bit. */
1064 	while (vdd_max >= vdd_min)
1065 		mask |= 1 << vdd_max--;
1066 
1067 	return mask;
1068 }
1069 
1070 static int mmc_of_get_func_num(struct device_node *node)
1071 {
1072 	u32 reg;
1073 	int ret;
1074 
1075 	ret = of_property_read_u32(node, "reg", &reg);
1076 	if (ret < 0)
1077 		return ret;
1078 
1079 	return reg;
1080 }
1081 
1082 struct device_node *mmc_of_find_child_device(struct mmc_host *host,
1083 		unsigned func_num)
1084 {
1085 	struct device_node *node;
1086 
1087 	if (!host->parent || !host->parent->of_node)
1088 		return NULL;
1089 
1090 	for_each_child_of_node(host->parent->of_node, node) {
1091 		if (mmc_of_get_func_num(node) == func_num)
1092 			return node;
1093 	}
1094 
1095 	return NULL;
1096 }
1097 
1098 /*
1099  * Mask off any voltages we don't support and select
1100  * the lowest voltage
1101  */
1102 u32 mmc_select_voltage(struct mmc_host *host, u32 ocr)
1103 {
1104 	int bit;
1105 
1106 	/*
1107 	 * Sanity check the voltages that the card claims to
1108 	 * support.
1109 	 */
1110 	if (ocr & 0x7F) {
1111 		dev_warn(mmc_dev(host),
1112 		"card claims to support voltages below defined range\n");
1113 		ocr &= ~0x7F;
1114 	}
1115 
1116 	ocr &= host->ocr_avail;
1117 	if (!ocr) {
1118 		dev_warn(mmc_dev(host), "no support for card's volts\n");
1119 		return 0;
1120 	}
1121 
1122 	if (host->caps2 & MMC_CAP2_FULL_PWR_CYCLE) {
1123 		bit = ffs(ocr) - 1;
1124 		ocr &= 3 << bit;
1125 		mmc_power_cycle(host, ocr);
1126 	} else {
1127 		bit = fls(ocr) - 1;
1128 		ocr &= 3 << bit;
1129 		if (bit != host->ios.vdd)
1130 			dev_warn(mmc_dev(host), "exceeding card's volts\n");
1131 	}
1132 
1133 	return ocr;
1134 }
1135 
1136 int mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage)
1137 {
1138 	int err = 0;
1139 	int old_signal_voltage = host->ios.signal_voltage;
1140 
1141 	host->ios.signal_voltage = signal_voltage;
1142 	if (host->ops->start_signal_voltage_switch)
1143 		err = host->ops->start_signal_voltage_switch(host, &host->ios);
1144 
1145 	if (err)
1146 		host->ios.signal_voltage = old_signal_voltage;
1147 
1148 	return err;
1149 
1150 }
1151 
1152 void mmc_set_initial_signal_voltage(struct mmc_host *host)
1153 {
1154 	/* Try to set signal voltage to 3.3V but fall back to 1.8v or 1.2v */
1155 	if (!mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330))
1156 		dev_dbg(mmc_dev(host), "Initial signal voltage of 3.3v\n");
1157 	else if (!mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180))
1158 		dev_dbg(mmc_dev(host), "Initial signal voltage of 1.8v\n");
1159 	else if (!mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120))
1160 		dev_dbg(mmc_dev(host), "Initial signal voltage of 1.2v\n");
1161 }
1162 
1163 int mmc_host_set_uhs_voltage(struct mmc_host *host)
1164 {
1165 	u32 clock;
1166 
1167 	/*
1168 	 * During a signal voltage level switch, the clock must be gated
1169 	 * for 5 ms according to the SD spec
1170 	 */
1171 	clock = host->ios.clock;
1172 	host->ios.clock = 0;
1173 	mmc_set_ios(host);
1174 
1175 	if (mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180))
1176 		return -EAGAIN;
1177 
1178 	/* Keep clock gated for at least 10 ms, though spec only says 5 ms */
1179 	mmc_delay(10);
1180 	host->ios.clock = clock;
1181 	mmc_set_ios(host);
1182 
1183 	return 0;
1184 }
1185 
1186 int mmc_set_uhs_voltage(struct mmc_host *host, u32 ocr)
1187 {
1188 	struct mmc_command cmd = {};
1189 	int err = 0;
1190 
1191 	/*
1192 	 * If we cannot switch voltages, return failure so the caller
1193 	 * can continue without UHS mode
1194 	 */
1195 	if (!host->ops->start_signal_voltage_switch)
1196 		return -EPERM;
1197 	if (!host->ops->card_busy)
1198 		pr_warn("%s: cannot verify signal voltage switch\n",
1199 			mmc_hostname(host));
1200 
1201 	cmd.opcode = SD_SWITCH_VOLTAGE;
1202 	cmd.arg = 0;
1203 	cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
1204 
1205 	err = mmc_wait_for_cmd(host, &cmd, 0);
1206 	if (err)
1207 		return err;
1208 
1209 	if (!mmc_host_is_spi(host) && (cmd.resp[0] & R1_ERROR))
1210 		return -EIO;
1211 
1212 	/*
1213 	 * The card should drive cmd and dat[0:3] low immediately
1214 	 * after the response of cmd11, but wait 1 ms to be sure
1215 	 */
1216 	mmc_delay(1);
1217 	if (host->ops->card_busy && !host->ops->card_busy(host)) {
1218 		err = -EAGAIN;
1219 		goto power_cycle;
1220 	}
1221 
1222 	if (mmc_host_set_uhs_voltage(host)) {
1223 		/*
1224 		 * Voltages may not have been switched, but we've already
1225 		 * sent CMD11, so a power cycle is required anyway
1226 		 */
1227 		err = -EAGAIN;
1228 		goto power_cycle;
1229 	}
1230 
1231 	/* Wait for at least 1 ms according to spec */
1232 	mmc_delay(1);
1233 
1234 	/*
1235 	 * Failure to switch is indicated by the card holding
1236 	 * dat[0:3] low
1237 	 */
1238 	if (host->ops->card_busy && host->ops->card_busy(host))
1239 		err = -EAGAIN;
1240 
1241 power_cycle:
1242 	if (err) {
1243 		pr_debug("%s: Signal voltage switch failed, "
1244 			"power cycling card\n", mmc_hostname(host));
1245 		mmc_power_cycle(host, ocr);
1246 	}
1247 
1248 	return err;
1249 }
1250 
1251 /*
1252  * Select timing parameters for host.
1253  */
1254 void mmc_set_timing(struct mmc_host *host, unsigned int timing)
1255 {
1256 	host->ios.timing = timing;
1257 	mmc_set_ios(host);
1258 }
1259 
1260 /*
1261  * Select appropriate driver type for host.
1262  */
1263 void mmc_set_driver_type(struct mmc_host *host, unsigned int drv_type)
1264 {
1265 	host->ios.drv_type = drv_type;
1266 	mmc_set_ios(host);
1267 }
1268 
1269 int mmc_select_drive_strength(struct mmc_card *card, unsigned int max_dtr,
1270 			      int card_drv_type, int *drv_type)
1271 {
1272 	struct mmc_host *host = card->host;
1273 	int host_drv_type = SD_DRIVER_TYPE_B;
1274 
1275 	*drv_type = 0;
1276 
1277 	if (!host->ops->select_drive_strength)
1278 		return 0;
1279 
1280 	/* Use SD definition of driver strength for hosts */
1281 	if (host->caps & MMC_CAP_DRIVER_TYPE_A)
1282 		host_drv_type |= SD_DRIVER_TYPE_A;
1283 
1284 	if (host->caps & MMC_CAP_DRIVER_TYPE_C)
1285 		host_drv_type |= SD_DRIVER_TYPE_C;
1286 
1287 	if (host->caps & MMC_CAP_DRIVER_TYPE_D)
1288 		host_drv_type |= SD_DRIVER_TYPE_D;
1289 
1290 	/*
1291 	 * The drive strength that the hardware can support
1292 	 * depends on the board design.  Pass the appropriate
1293 	 * information and let the hardware specific code
1294 	 * return what is possible given the options
1295 	 */
1296 	return host->ops->select_drive_strength(card, max_dtr,
1297 						host_drv_type,
1298 						card_drv_type,
1299 						drv_type);
1300 }
1301 
1302 /*
1303  * Apply power to the MMC stack.  This is a two-stage process.
1304  * First, we enable power to the card without the clock running.
1305  * We then wait a bit for the power to stabilise.  Finally,
1306  * enable the bus drivers and clock to the card.
1307  *
1308  * We must _NOT_ enable the clock prior to power stablising.
1309  *
1310  * If a host does all the power sequencing itself, ignore the
1311  * initial MMC_POWER_UP stage.
1312  */
1313 void mmc_power_up(struct mmc_host *host, u32 ocr)
1314 {
1315 	if (host->ios.power_mode == MMC_POWER_ON)
1316 		return;
1317 
1318 	mmc_pwrseq_pre_power_on(host);
1319 
1320 	host->ios.vdd = fls(ocr) - 1;
1321 	host->ios.power_mode = MMC_POWER_UP;
1322 	/* Set initial state and call mmc_set_ios */
1323 	mmc_set_initial_state(host);
1324 
1325 	mmc_set_initial_signal_voltage(host);
1326 
1327 	/*
1328 	 * This delay should be sufficient to allow the power supply
1329 	 * to reach the minimum voltage.
1330 	 */
1331 	mmc_delay(host->ios.power_delay_ms);
1332 
1333 	mmc_pwrseq_post_power_on(host);
1334 
1335 	host->ios.clock = host->f_init;
1336 
1337 	host->ios.power_mode = MMC_POWER_ON;
1338 	mmc_set_ios(host);
1339 
1340 	/*
1341 	 * This delay must be at least 74 clock sizes, or 1 ms, or the
1342 	 * time required to reach a stable voltage.
1343 	 */
1344 	mmc_delay(host->ios.power_delay_ms);
1345 }
1346 
1347 void mmc_power_off(struct mmc_host *host)
1348 {
1349 	if (host->ios.power_mode == MMC_POWER_OFF)
1350 		return;
1351 
1352 	mmc_pwrseq_power_off(host);
1353 
1354 	host->ios.clock = 0;
1355 	host->ios.vdd = 0;
1356 
1357 	host->ios.power_mode = MMC_POWER_OFF;
1358 	/* Set initial state and call mmc_set_ios */
1359 	mmc_set_initial_state(host);
1360 
1361 	/*
1362 	 * Some configurations, such as the 802.11 SDIO card in the OLPC
1363 	 * XO-1.5, require a short delay after poweroff before the card
1364 	 * can be successfully turned on again.
1365 	 */
1366 	mmc_delay(1);
1367 }
1368 
1369 void mmc_power_cycle(struct mmc_host *host, u32 ocr)
1370 {
1371 	mmc_power_off(host);
1372 	/* Wait at least 1 ms according to SD spec */
1373 	mmc_delay(1);
1374 	mmc_power_up(host, ocr);
1375 }
1376 
1377 /*
1378  * Cleanup when the last reference to the bus operator is dropped.
1379  */
1380 static void __mmc_release_bus(struct mmc_host *host)
1381 {
1382 	WARN_ON(!host->bus_dead);
1383 
1384 	host->bus_ops = NULL;
1385 }
1386 
1387 /*
1388  * Increase reference count of bus operator
1389  */
1390 static inline void mmc_bus_get(struct mmc_host *host)
1391 {
1392 	unsigned long flags;
1393 
1394 	spin_lock_irqsave(&host->lock, flags);
1395 	host->bus_refs++;
1396 	spin_unlock_irqrestore(&host->lock, flags);
1397 }
1398 
1399 /*
1400  * Decrease reference count of bus operator and free it if
1401  * it is the last reference.
1402  */
1403 static inline void mmc_bus_put(struct mmc_host *host)
1404 {
1405 	unsigned long flags;
1406 
1407 	spin_lock_irqsave(&host->lock, flags);
1408 	host->bus_refs--;
1409 	if ((host->bus_refs == 0) && host->bus_ops)
1410 		__mmc_release_bus(host);
1411 	spin_unlock_irqrestore(&host->lock, flags);
1412 }
1413 
1414 /*
1415  * Assign a mmc bus handler to a host. Only one bus handler may control a
1416  * host at any given time.
1417  */
1418 void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops)
1419 {
1420 	unsigned long flags;
1421 
1422 	WARN_ON(!host->claimed);
1423 
1424 	spin_lock_irqsave(&host->lock, flags);
1425 
1426 	WARN_ON(host->bus_ops);
1427 	WARN_ON(host->bus_refs);
1428 
1429 	host->bus_ops = ops;
1430 	host->bus_refs = 1;
1431 	host->bus_dead = 0;
1432 
1433 	spin_unlock_irqrestore(&host->lock, flags);
1434 }
1435 
1436 /*
1437  * Remove the current bus handler from a host.
1438  */
1439 void mmc_detach_bus(struct mmc_host *host)
1440 {
1441 	unsigned long flags;
1442 
1443 	WARN_ON(!host->claimed);
1444 	WARN_ON(!host->bus_ops);
1445 
1446 	spin_lock_irqsave(&host->lock, flags);
1447 
1448 	host->bus_dead = 1;
1449 
1450 	spin_unlock_irqrestore(&host->lock, flags);
1451 
1452 	mmc_bus_put(host);
1453 }
1454 
1455 void _mmc_detect_change(struct mmc_host *host, unsigned long delay, bool cd_irq)
1456 {
1457 	/*
1458 	 * If the device is configured as wakeup, we prevent a new sleep for
1459 	 * 5 s to give provision for user space to consume the event.
1460 	 */
1461 	if (cd_irq && !(host->caps & MMC_CAP_NEEDS_POLL) &&
1462 		device_can_wakeup(mmc_dev(host)))
1463 		pm_wakeup_event(mmc_dev(host), 5000);
1464 
1465 	host->detect_change = 1;
1466 	mmc_schedule_delayed_work(&host->detect, delay);
1467 }
1468 
1469 /**
1470  *	mmc_detect_change - process change of state on a MMC socket
1471  *	@host: host which changed state.
1472  *	@delay: optional delay to wait before detection (jiffies)
1473  *
1474  *	MMC drivers should call this when they detect a card has been
1475  *	inserted or removed. The MMC layer will confirm that any
1476  *	present card is still functional, and initialize any newly
1477  *	inserted.
1478  */
1479 void mmc_detect_change(struct mmc_host *host, unsigned long delay)
1480 {
1481 	_mmc_detect_change(host, delay, true);
1482 }
1483 EXPORT_SYMBOL(mmc_detect_change);
1484 
1485 void mmc_init_erase(struct mmc_card *card)
1486 {
1487 	unsigned int sz;
1488 
1489 	if (is_power_of_2(card->erase_size))
1490 		card->erase_shift = ffs(card->erase_size) - 1;
1491 	else
1492 		card->erase_shift = 0;
1493 
1494 	/*
1495 	 * It is possible to erase an arbitrarily large area of an SD or MMC
1496 	 * card.  That is not desirable because it can take a long time
1497 	 * (minutes) potentially delaying more important I/O, and also the
1498 	 * timeout calculations become increasingly hugely over-estimated.
1499 	 * Consequently, 'pref_erase' is defined as a guide to limit erases
1500 	 * to that size and alignment.
1501 	 *
1502 	 * For SD cards that define Allocation Unit size, limit erases to one
1503 	 * Allocation Unit at a time.
1504 	 * For MMC, have a stab at ai good value and for modern cards it will
1505 	 * end up being 4MiB. Note that if the value is too small, it can end
1506 	 * up taking longer to erase. Also note, erase_size is already set to
1507 	 * High Capacity Erase Size if available when this function is called.
1508 	 */
1509 	if (mmc_card_sd(card) && card->ssr.au) {
1510 		card->pref_erase = card->ssr.au;
1511 		card->erase_shift = ffs(card->ssr.au) - 1;
1512 	} else if (card->erase_size) {
1513 		sz = (card->csd.capacity << (card->csd.read_blkbits - 9)) >> 11;
1514 		if (sz < 128)
1515 			card->pref_erase = 512 * 1024 / 512;
1516 		else if (sz < 512)
1517 			card->pref_erase = 1024 * 1024 / 512;
1518 		else if (sz < 1024)
1519 			card->pref_erase = 2 * 1024 * 1024 / 512;
1520 		else
1521 			card->pref_erase = 4 * 1024 * 1024 / 512;
1522 		if (card->pref_erase < card->erase_size)
1523 			card->pref_erase = card->erase_size;
1524 		else {
1525 			sz = card->pref_erase % card->erase_size;
1526 			if (sz)
1527 				card->pref_erase += card->erase_size - sz;
1528 		}
1529 	} else
1530 		card->pref_erase = 0;
1531 }
1532 
1533 static unsigned int mmc_mmc_erase_timeout(struct mmc_card *card,
1534 				          unsigned int arg, unsigned int qty)
1535 {
1536 	unsigned int erase_timeout;
1537 
1538 	if (arg == MMC_DISCARD_ARG ||
1539 	    (arg == MMC_TRIM_ARG && card->ext_csd.rev >= 6)) {
1540 		erase_timeout = card->ext_csd.trim_timeout;
1541 	} else if (card->ext_csd.erase_group_def & 1) {
1542 		/* High Capacity Erase Group Size uses HC timeouts */
1543 		if (arg == MMC_TRIM_ARG)
1544 			erase_timeout = card->ext_csd.trim_timeout;
1545 		else
1546 			erase_timeout = card->ext_csd.hc_erase_timeout;
1547 	} else {
1548 		/* CSD Erase Group Size uses write timeout */
1549 		unsigned int mult = (10 << card->csd.r2w_factor);
1550 		unsigned int timeout_clks = card->csd.taac_clks * mult;
1551 		unsigned int timeout_us;
1552 
1553 		/* Avoid overflow: e.g. taac_ns=80000000 mult=1280 */
1554 		if (card->csd.taac_ns < 1000000)
1555 			timeout_us = (card->csd.taac_ns * mult) / 1000;
1556 		else
1557 			timeout_us = (card->csd.taac_ns / 1000) * mult;
1558 
1559 		/*
1560 		 * ios.clock is only a target.  The real clock rate might be
1561 		 * less but not that much less, so fudge it by multiplying by 2.
1562 		 */
1563 		timeout_clks <<= 1;
1564 		timeout_us += (timeout_clks * 1000) /
1565 			      (card->host->ios.clock / 1000);
1566 
1567 		erase_timeout = timeout_us / 1000;
1568 
1569 		/*
1570 		 * Theoretically, the calculation could underflow so round up
1571 		 * to 1ms in that case.
1572 		 */
1573 		if (!erase_timeout)
1574 			erase_timeout = 1;
1575 	}
1576 
1577 	/* Multiplier for secure operations */
1578 	if (arg & MMC_SECURE_ARGS) {
1579 		if (arg == MMC_SECURE_ERASE_ARG)
1580 			erase_timeout *= card->ext_csd.sec_erase_mult;
1581 		else
1582 			erase_timeout *= card->ext_csd.sec_trim_mult;
1583 	}
1584 
1585 	erase_timeout *= qty;
1586 
1587 	/*
1588 	 * Ensure at least a 1 second timeout for SPI as per
1589 	 * 'mmc_set_data_timeout()'
1590 	 */
1591 	if (mmc_host_is_spi(card->host) && erase_timeout < 1000)
1592 		erase_timeout = 1000;
1593 
1594 	return erase_timeout;
1595 }
1596 
1597 static unsigned int mmc_sd_erase_timeout(struct mmc_card *card,
1598 					 unsigned int arg,
1599 					 unsigned int qty)
1600 {
1601 	unsigned int erase_timeout;
1602 
1603 	/* for DISCARD none of the below calculation applies.
1604 	 * the busy timeout is 250msec per discard command.
1605 	 */
1606 	if (arg == SD_DISCARD_ARG)
1607 		return SD_DISCARD_TIMEOUT_MS;
1608 
1609 	if (card->ssr.erase_timeout) {
1610 		/* Erase timeout specified in SD Status Register (SSR) */
1611 		erase_timeout = card->ssr.erase_timeout * qty +
1612 				card->ssr.erase_offset;
1613 	} else {
1614 		/*
1615 		 * Erase timeout not specified in SD Status Register (SSR) so
1616 		 * use 250ms per write block.
1617 		 */
1618 		erase_timeout = 250 * qty;
1619 	}
1620 
1621 	/* Must not be less than 1 second */
1622 	if (erase_timeout < 1000)
1623 		erase_timeout = 1000;
1624 
1625 	return erase_timeout;
1626 }
1627 
1628 static unsigned int mmc_erase_timeout(struct mmc_card *card,
1629 				      unsigned int arg,
1630 				      unsigned int qty)
1631 {
1632 	if (mmc_card_sd(card))
1633 		return mmc_sd_erase_timeout(card, arg, qty);
1634 	else
1635 		return mmc_mmc_erase_timeout(card, arg, qty);
1636 }
1637 
1638 static int mmc_do_erase(struct mmc_card *card, unsigned int from,
1639 			unsigned int to, unsigned int arg)
1640 {
1641 	struct mmc_command cmd = {};
1642 	unsigned int qty = 0, busy_timeout = 0;
1643 	bool use_r1b_resp = false;
1644 	int err;
1645 
1646 	mmc_retune_hold(card->host);
1647 
1648 	/*
1649 	 * qty is used to calculate the erase timeout which depends on how many
1650 	 * erase groups (or allocation units in SD terminology) are affected.
1651 	 * We count erasing part of an erase group as one erase group.
1652 	 * For SD, the allocation units are always a power of 2.  For MMC, the
1653 	 * erase group size is almost certainly also power of 2, but it does not
1654 	 * seem to insist on that in the JEDEC standard, so we fall back to
1655 	 * division in that case.  SD may not specify an allocation unit size,
1656 	 * in which case the timeout is based on the number of write blocks.
1657 	 *
1658 	 * Note that the timeout for secure trim 2 will only be correct if the
1659 	 * number of erase groups specified is the same as the total of all
1660 	 * preceding secure trim 1 commands.  Since the power may have been
1661 	 * lost since the secure trim 1 commands occurred, it is generally
1662 	 * impossible to calculate the secure trim 2 timeout correctly.
1663 	 */
1664 	if (card->erase_shift)
1665 		qty += ((to >> card->erase_shift) -
1666 			(from >> card->erase_shift)) + 1;
1667 	else if (mmc_card_sd(card))
1668 		qty += to - from + 1;
1669 	else
1670 		qty += ((to / card->erase_size) -
1671 			(from / card->erase_size)) + 1;
1672 
1673 	if (!mmc_card_blockaddr(card)) {
1674 		from <<= 9;
1675 		to <<= 9;
1676 	}
1677 
1678 	if (mmc_card_sd(card))
1679 		cmd.opcode = SD_ERASE_WR_BLK_START;
1680 	else
1681 		cmd.opcode = MMC_ERASE_GROUP_START;
1682 	cmd.arg = from;
1683 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
1684 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
1685 	if (err) {
1686 		pr_err("mmc_erase: group start error %d, "
1687 		       "status %#x\n", err, cmd.resp[0]);
1688 		err = -EIO;
1689 		goto out;
1690 	}
1691 
1692 	memset(&cmd, 0, sizeof(struct mmc_command));
1693 	if (mmc_card_sd(card))
1694 		cmd.opcode = SD_ERASE_WR_BLK_END;
1695 	else
1696 		cmd.opcode = MMC_ERASE_GROUP_END;
1697 	cmd.arg = to;
1698 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
1699 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
1700 	if (err) {
1701 		pr_err("mmc_erase: group end error %d, status %#x\n",
1702 		       err, cmd.resp[0]);
1703 		err = -EIO;
1704 		goto out;
1705 	}
1706 
1707 	memset(&cmd, 0, sizeof(struct mmc_command));
1708 	cmd.opcode = MMC_ERASE;
1709 	cmd.arg = arg;
1710 	busy_timeout = mmc_erase_timeout(card, arg, qty);
1711 	/*
1712 	 * If the host controller supports busy signalling and the timeout for
1713 	 * the erase operation does not exceed the max_busy_timeout, we should
1714 	 * use R1B response. Or we need to prevent the host from doing hw busy
1715 	 * detection, which is done by converting to a R1 response instead.
1716 	 * Note, some hosts requires R1B, which also means they are on their own
1717 	 * when it comes to deal with the busy timeout.
1718 	 */
1719 	if (!(card->host->caps & MMC_CAP_NEED_RSP_BUSY) &&
1720 	    card->host->max_busy_timeout &&
1721 	    busy_timeout > card->host->max_busy_timeout) {
1722 		cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
1723 	} else {
1724 		cmd.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
1725 		cmd.busy_timeout = busy_timeout;
1726 		use_r1b_resp = true;
1727 	}
1728 
1729 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
1730 	if (err) {
1731 		pr_err("mmc_erase: erase error %d, status %#x\n",
1732 		       err, cmd.resp[0]);
1733 		err = -EIO;
1734 		goto out;
1735 	}
1736 
1737 	if (mmc_host_is_spi(card->host))
1738 		goto out;
1739 
1740 	/*
1741 	 * In case of when R1B + MMC_CAP_WAIT_WHILE_BUSY is used, the polling
1742 	 * shall be avoided.
1743 	 */
1744 	if ((card->host->caps & MMC_CAP_WAIT_WHILE_BUSY) && use_r1b_resp)
1745 		goto out;
1746 
1747 	/* Let's poll to find out when the erase operation completes. */
1748 	err = mmc_poll_for_busy(card, busy_timeout, MMC_BUSY_ERASE);
1749 
1750 out:
1751 	mmc_retune_release(card->host);
1752 	return err;
1753 }
1754 
1755 static unsigned int mmc_align_erase_size(struct mmc_card *card,
1756 					 unsigned int *from,
1757 					 unsigned int *to,
1758 					 unsigned int nr)
1759 {
1760 	unsigned int from_new = *from, nr_new = nr, rem;
1761 
1762 	/*
1763 	 * When the 'card->erase_size' is power of 2, we can use round_up/down()
1764 	 * to align the erase size efficiently.
1765 	 */
1766 	if (is_power_of_2(card->erase_size)) {
1767 		unsigned int temp = from_new;
1768 
1769 		from_new = round_up(temp, card->erase_size);
1770 		rem = from_new - temp;
1771 
1772 		if (nr_new > rem)
1773 			nr_new -= rem;
1774 		else
1775 			return 0;
1776 
1777 		nr_new = round_down(nr_new, card->erase_size);
1778 	} else {
1779 		rem = from_new % card->erase_size;
1780 		if (rem) {
1781 			rem = card->erase_size - rem;
1782 			from_new += rem;
1783 			if (nr_new > rem)
1784 				nr_new -= rem;
1785 			else
1786 				return 0;
1787 		}
1788 
1789 		rem = nr_new % card->erase_size;
1790 		if (rem)
1791 			nr_new -= rem;
1792 	}
1793 
1794 	if (nr_new == 0)
1795 		return 0;
1796 
1797 	*to = from_new + nr_new;
1798 	*from = from_new;
1799 
1800 	return nr_new;
1801 }
1802 
1803 /**
1804  * mmc_erase - erase sectors.
1805  * @card: card to erase
1806  * @from: first sector to erase
1807  * @nr: number of sectors to erase
1808  * @arg: erase command argument
1809  *
1810  * Caller must claim host before calling this function.
1811  */
1812 int mmc_erase(struct mmc_card *card, unsigned int from, unsigned int nr,
1813 	      unsigned int arg)
1814 {
1815 	unsigned int rem, to = from + nr;
1816 	int err;
1817 
1818 	if (!(card->csd.cmdclass & CCC_ERASE))
1819 		return -EOPNOTSUPP;
1820 
1821 	if (!card->erase_size)
1822 		return -EOPNOTSUPP;
1823 
1824 	if (mmc_card_sd(card) && arg != SD_ERASE_ARG && arg != SD_DISCARD_ARG)
1825 		return -EOPNOTSUPP;
1826 
1827 	if (mmc_card_mmc(card) && (arg & MMC_SECURE_ARGS) &&
1828 	    !(card->ext_csd.sec_feature_support & EXT_CSD_SEC_ER_EN))
1829 		return -EOPNOTSUPP;
1830 
1831 	if (mmc_card_mmc(card) && (arg & MMC_TRIM_ARGS) &&
1832 	    !(card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN))
1833 		return -EOPNOTSUPP;
1834 
1835 	if (arg == MMC_SECURE_ERASE_ARG) {
1836 		if (from % card->erase_size || nr % card->erase_size)
1837 			return -EINVAL;
1838 	}
1839 
1840 	if (arg == MMC_ERASE_ARG)
1841 		nr = mmc_align_erase_size(card, &from, &to, nr);
1842 
1843 	if (nr == 0)
1844 		return 0;
1845 
1846 	if (to <= from)
1847 		return -EINVAL;
1848 
1849 	/* 'from' and 'to' are inclusive */
1850 	to -= 1;
1851 
1852 	/*
1853 	 * Special case where only one erase-group fits in the timeout budget:
1854 	 * If the region crosses an erase-group boundary on this particular
1855 	 * case, we will be trimming more than one erase-group which, does not
1856 	 * fit in the timeout budget of the controller, so we need to split it
1857 	 * and call mmc_do_erase() twice if necessary. This special case is
1858 	 * identified by the card->eg_boundary flag.
1859 	 */
1860 	rem = card->erase_size - (from % card->erase_size);
1861 	if ((arg & MMC_TRIM_ARGS) && (card->eg_boundary) && (nr > rem)) {
1862 		err = mmc_do_erase(card, from, from + rem - 1, arg);
1863 		from += rem;
1864 		if ((err) || (to <= from))
1865 			return err;
1866 	}
1867 
1868 	return mmc_do_erase(card, from, to, arg);
1869 }
1870 EXPORT_SYMBOL(mmc_erase);
1871 
1872 int mmc_can_erase(struct mmc_card *card)
1873 {
1874 	if (card->csd.cmdclass & CCC_ERASE && card->erase_size)
1875 		return 1;
1876 	return 0;
1877 }
1878 EXPORT_SYMBOL(mmc_can_erase);
1879 
1880 int mmc_can_trim(struct mmc_card *card)
1881 {
1882 	if ((card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN) &&
1883 	    (!(card->quirks & MMC_QUIRK_TRIM_BROKEN)))
1884 		return 1;
1885 	return 0;
1886 }
1887 EXPORT_SYMBOL(mmc_can_trim);
1888 
1889 int mmc_can_discard(struct mmc_card *card)
1890 {
1891 	/*
1892 	 * As there's no way to detect the discard support bit at v4.5
1893 	 * use the s/w feature support filed.
1894 	 */
1895 	if (card->ext_csd.feature_support & MMC_DISCARD_FEATURE)
1896 		return 1;
1897 	return 0;
1898 }
1899 EXPORT_SYMBOL(mmc_can_discard);
1900 
1901 int mmc_can_sanitize(struct mmc_card *card)
1902 {
1903 	if (!mmc_can_trim(card) && !mmc_can_erase(card))
1904 		return 0;
1905 	if (card->ext_csd.sec_feature_support & EXT_CSD_SEC_SANITIZE)
1906 		return 1;
1907 	return 0;
1908 }
1909 
1910 int mmc_can_secure_erase_trim(struct mmc_card *card)
1911 {
1912 	if ((card->ext_csd.sec_feature_support & EXT_CSD_SEC_ER_EN) &&
1913 	    !(card->quirks & MMC_QUIRK_SEC_ERASE_TRIM_BROKEN))
1914 		return 1;
1915 	return 0;
1916 }
1917 EXPORT_SYMBOL(mmc_can_secure_erase_trim);
1918 
1919 int mmc_erase_group_aligned(struct mmc_card *card, unsigned int from,
1920 			    unsigned int nr)
1921 {
1922 	if (!card->erase_size)
1923 		return 0;
1924 	if (from % card->erase_size || nr % card->erase_size)
1925 		return 0;
1926 	return 1;
1927 }
1928 EXPORT_SYMBOL(mmc_erase_group_aligned);
1929 
1930 static unsigned int mmc_do_calc_max_discard(struct mmc_card *card,
1931 					    unsigned int arg)
1932 {
1933 	struct mmc_host *host = card->host;
1934 	unsigned int max_discard, x, y, qty = 0, max_qty, min_qty, timeout;
1935 	unsigned int last_timeout = 0;
1936 	unsigned int max_busy_timeout = host->max_busy_timeout ?
1937 			host->max_busy_timeout : MMC_ERASE_TIMEOUT_MS;
1938 
1939 	if (card->erase_shift) {
1940 		max_qty = UINT_MAX >> card->erase_shift;
1941 		min_qty = card->pref_erase >> card->erase_shift;
1942 	} else if (mmc_card_sd(card)) {
1943 		max_qty = UINT_MAX;
1944 		min_qty = card->pref_erase;
1945 	} else {
1946 		max_qty = UINT_MAX / card->erase_size;
1947 		min_qty = card->pref_erase / card->erase_size;
1948 	}
1949 
1950 	/*
1951 	 * We should not only use 'host->max_busy_timeout' as the limitation
1952 	 * when deciding the max discard sectors. We should set a balance value
1953 	 * to improve the erase speed, and it can not get too long timeout at
1954 	 * the same time.
1955 	 *
1956 	 * Here we set 'card->pref_erase' as the minimal discard sectors no
1957 	 * matter what size of 'host->max_busy_timeout', but if the
1958 	 * 'host->max_busy_timeout' is large enough for more discard sectors,
1959 	 * then we can continue to increase the max discard sectors until we
1960 	 * get a balance value. In cases when the 'host->max_busy_timeout'
1961 	 * isn't specified, use the default max erase timeout.
1962 	 */
1963 	do {
1964 		y = 0;
1965 		for (x = 1; x && x <= max_qty && max_qty - x >= qty; x <<= 1) {
1966 			timeout = mmc_erase_timeout(card, arg, qty + x);
1967 
1968 			if (qty + x > min_qty && timeout > max_busy_timeout)
1969 				break;
1970 
1971 			if (timeout < last_timeout)
1972 				break;
1973 			last_timeout = timeout;
1974 			y = x;
1975 		}
1976 		qty += y;
1977 	} while (y);
1978 
1979 	if (!qty)
1980 		return 0;
1981 
1982 	/*
1983 	 * When specifying a sector range to trim, chances are we might cross
1984 	 * an erase-group boundary even if the amount of sectors is less than
1985 	 * one erase-group.
1986 	 * If we can only fit one erase-group in the controller timeout budget,
1987 	 * we have to care that erase-group boundaries are not crossed by a
1988 	 * single trim operation. We flag that special case with "eg_boundary".
1989 	 * In all other cases we can just decrement qty and pretend that we
1990 	 * always touch (qty + 1) erase-groups as a simple optimization.
1991 	 */
1992 	if (qty == 1)
1993 		card->eg_boundary = 1;
1994 	else
1995 		qty--;
1996 
1997 	/* Convert qty to sectors */
1998 	if (card->erase_shift)
1999 		max_discard = qty << card->erase_shift;
2000 	else if (mmc_card_sd(card))
2001 		max_discard = qty + 1;
2002 	else
2003 		max_discard = qty * card->erase_size;
2004 
2005 	return max_discard;
2006 }
2007 
2008 unsigned int mmc_calc_max_discard(struct mmc_card *card)
2009 {
2010 	struct mmc_host *host = card->host;
2011 	unsigned int max_discard, max_trim;
2012 
2013 	/*
2014 	 * Without erase_group_def set, MMC erase timeout depends on clock
2015 	 * frequence which can change.  In that case, the best choice is
2016 	 * just the preferred erase size.
2017 	 */
2018 	if (mmc_card_mmc(card) && !(card->ext_csd.erase_group_def & 1))
2019 		return card->pref_erase;
2020 
2021 	max_discard = mmc_do_calc_max_discard(card, MMC_ERASE_ARG);
2022 	if (mmc_can_trim(card)) {
2023 		max_trim = mmc_do_calc_max_discard(card, MMC_TRIM_ARG);
2024 		if (max_trim < max_discard || max_discard == 0)
2025 			max_discard = max_trim;
2026 	} else if (max_discard < card->erase_size) {
2027 		max_discard = 0;
2028 	}
2029 	pr_debug("%s: calculated max. discard sectors %u for timeout %u ms\n",
2030 		mmc_hostname(host), max_discard, host->max_busy_timeout ?
2031 		host->max_busy_timeout : MMC_ERASE_TIMEOUT_MS);
2032 	return max_discard;
2033 }
2034 EXPORT_SYMBOL(mmc_calc_max_discard);
2035 
2036 bool mmc_card_is_blockaddr(struct mmc_card *card)
2037 {
2038 	return card ? mmc_card_blockaddr(card) : false;
2039 }
2040 EXPORT_SYMBOL(mmc_card_is_blockaddr);
2041 
2042 int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen)
2043 {
2044 	struct mmc_command cmd = {};
2045 
2046 	if (mmc_card_blockaddr(card) || mmc_card_ddr52(card) ||
2047 	    mmc_card_hs400(card) || mmc_card_hs400es(card))
2048 		return 0;
2049 
2050 	cmd.opcode = MMC_SET_BLOCKLEN;
2051 	cmd.arg = blocklen;
2052 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
2053 	return mmc_wait_for_cmd(card->host, &cmd, 5);
2054 }
2055 EXPORT_SYMBOL(mmc_set_blocklen);
2056 
2057 static void mmc_hw_reset_for_init(struct mmc_host *host)
2058 {
2059 	mmc_pwrseq_reset(host);
2060 
2061 	if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
2062 		return;
2063 	host->ops->hw_reset(host);
2064 }
2065 
2066 int mmc_hw_reset(struct mmc_host *host)
2067 {
2068 	int ret;
2069 
2070 	if (!host->card)
2071 		return -EINVAL;
2072 
2073 	mmc_bus_get(host);
2074 	if (!host->bus_ops || host->bus_dead || !host->bus_ops->hw_reset) {
2075 		mmc_bus_put(host);
2076 		return -EOPNOTSUPP;
2077 	}
2078 
2079 	ret = host->bus_ops->hw_reset(host);
2080 	mmc_bus_put(host);
2081 
2082 	if (ret < 0)
2083 		pr_warn("%s: tried to HW reset card, got error %d\n",
2084 			mmc_hostname(host), ret);
2085 
2086 	return ret;
2087 }
2088 EXPORT_SYMBOL(mmc_hw_reset);
2089 
2090 int mmc_sw_reset(struct mmc_host *host)
2091 {
2092 	int ret;
2093 
2094 	if (!host->card)
2095 		return -EINVAL;
2096 
2097 	mmc_bus_get(host);
2098 	if (!host->bus_ops || host->bus_dead || !host->bus_ops->sw_reset) {
2099 		mmc_bus_put(host);
2100 		return -EOPNOTSUPP;
2101 	}
2102 
2103 	ret = host->bus_ops->sw_reset(host);
2104 	mmc_bus_put(host);
2105 
2106 	if (ret)
2107 		pr_warn("%s: tried to SW reset card, got error %d\n",
2108 			mmc_hostname(host), ret);
2109 
2110 	return ret;
2111 }
2112 EXPORT_SYMBOL(mmc_sw_reset);
2113 
2114 static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
2115 {
2116 	host->f_init = freq;
2117 
2118 	pr_debug("%s: %s: trying to init card at %u Hz\n",
2119 		mmc_hostname(host), __func__, host->f_init);
2120 
2121 	mmc_power_up(host, host->ocr_avail);
2122 
2123 	/*
2124 	 * Some eMMCs (with VCCQ always on) may not be reset after power up, so
2125 	 * do a hardware reset if possible.
2126 	 */
2127 	mmc_hw_reset_for_init(host);
2128 
2129 	/*
2130 	 * sdio_reset sends CMD52 to reset card.  Since we do not know
2131 	 * if the card is being re-initialized, just send it.  CMD52
2132 	 * should be ignored by SD/eMMC cards.
2133 	 * Skip it if we already know that we do not support SDIO commands
2134 	 */
2135 	if (!(host->caps2 & MMC_CAP2_NO_SDIO))
2136 		sdio_reset(host);
2137 
2138 	mmc_go_idle(host);
2139 
2140 	if (!(host->caps2 & MMC_CAP2_NO_SD))
2141 		mmc_send_if_cond(host, host->ocr_avail);
2142 
2143 	/* Order's important: probe SDIO, then SD, then MMC */
2144 	if (!(host->caps2 & MMC_CAP2_NO_SDIO))
2145 		if (!mmc_attach_sdio(host))
2146 			return 0;
2147 
2148 	if (!(host->caps2 & MMC_CAP2_NO_SD))
2149 		if (!mmc_attach_sd(host))
2150 			return 0;
2151 
2152 	if (!(host->caps2 & MMC_CAP2_NO_MMC))
2153 		if (!mmc_attach_mmc(host))
2154 			return 0;
2155 
2156 	mmc_power_off(host);
2157 	return -EIO;
2158 }
2159 
2160 int _mmc_detect_card_removed(struct mmc_host *host)
2161 {
2162 	int ret;
2163 
2164 	if (!host->card || mmc_card_removed(host->card))
2165 		return 1;
2166 
2167 	ret = host->bus_ops->alive(host);
2168 
2169 	/*
2170 	 * Card detect status and alive check may be out of sync if card is
2171 	 * removed slowly, when card detect switch changes while card/slot
2172 	 * pads are still contacted in hardware (refer to "SD Card Mechanical
2173 	 * Addendum, Appendix C: Card Detection Switch"). So reschedule a
2174 	 * detect work 200ms later for this case.
2175 	 */
2176 	if (!ret && host->ops->get_cd && !host->ops->get_cd(host)) {
2177 		mmc_detect_change(host, msecs_to_jiffies(200));
2178 		pr_debug("%s: card removed too slowly\n", mmc_hostname(host));
2179 	}
2180 
2181 	if (ret) {
2182 		mmc_card_set_removed(host->card);
2183 		pr_debug("%s: card remove detected\n", mmc_hostname(host));
2184 	}
2185 
2186 	return ret;
2187 }
2188 
2189 int mmc_detect_card_removed(struct mmc_host *host)
2190 {
2191 	struct mmc_card *card = host->card;
2192 	int ret;
2193 
2194 	WARN_ON(!host->claimed);
2195 
2196 	if (!card)
2197 		return 1;
2198 
2199 	if (!mmc_card_is_removable(host))
2200 		return 0;
2201 
2202 	ret = mmc_card_removed(card);
2203 	/*
2204 	 * The card will be considered unchanged unless we have been asked to
2205 	 * detect a change or host requires polling to provide card detection.
2206 	 */
2207 	if (!host->detect_change && !(host->caps & MMC_CAP_NEEDS_POLL))
2208 		return ret;
2209 
2210 	host->detect_change = 0;
2211 	if (!ret) {
2212 		ret = _mmc_detect_card_removed(host);
2213 		if (ret && (host->caps & MMC_CAP_NEEDS_POLL)) {
2214 			/*
2215 			 * Schedule a detect work as soon as possible to let a
2216 			 * rescan handle the card removal.
2217 			 */
2218 			cancel_delayed_work(&host->detect);
2219 			_mmc_detect_change(host, 0, false);
2220 		}
2221 	}
2222 
2223 	return ret;
2224 }
2225 EXPORT_SYMBOL(mmc_detect_card_removed);
2226 
2227 void mmc_rescan(struct work_struct *work)
2228 {
2229 	struct mmc_host *host =
2230 		container_of(work, struct mmc_host, detect.work);
2231 	int i;
2232 
2233 	if (host->rescan_disable)
2234 		return;
2235 
2236 	/* If there is a non-removable card registered, only scan once */
2237 	if (!mmc_card_is_removable(host) && host->rescan_entered)
2238 		return;
2239 	host->rescan_entered = 1;
2240 
2241 	if (host->trigger_card_event && host->ops->card_event) {
2242 		mmc_claim_host(host);
2243 		host->ops->card_event(host);
2244 		mmc_release_host(host);
2245 		host->trigger_card_event = false;
2246 	}
2247 
2248 	mmc_bus_get(host);
2249 
2250 	/* Verify a registered card to be functional, else remove it. */
2251 	if (host->bus_ops && !host->bus_dead)
2252 		host->bus_ops->detect(host);
2253 
2254 	host->detect_change = 0;
2255 
2256 	/*
2257 	 * Let mmc_bus_put() free the bus/bus_ops if we've found that
2258 	 * the card is no longer present.
2259 	 */
2260 	mmc_bus_put(host);
2261 	mmc_bus_get(host);
2262 
2263 	/* if there still is a card present, stop here */
2264 	if (host->bus_ops != NULL) {
2265 		mmc_bus_put(host);
2266 		goto out;
2267 	}
2268 
2269 	/*
2270 	 * Only we can add a new handler, so it's safe to
2271 	 * release the lock here.
2272 	 */
2273 	mmc_bus_put(host);
2274 
2275 	mmc_claim_host(host);
2276 	if (mmc_card_is_removable(host) && host->ops->get_cd &&
2277 			host->ops->get_cd(host) == 0) {
2278 		mmc_power_off(host);
2279 		mmc_release_host(host);
2280 		goto out;
2281 	}
2282 
2283 	for (i = 0; i < ARRAY_SIZE(freqs); i++) {
2284 		unsigned int freq = freqs[i];
2285 		if (freq > host->f_max) {
2286 			if (i + 1 < ARRAY_SIZE(freqs))
2287 				continue;
2288 			freq = host->f_max;
2289 		}
2290 		if (!mmc_rescan_try_freq(host, max(freq, host->f_min)))
2291 			break;
2292 		if (freqs[i] <= host->f_min)
2293 			break;
2294 	}
2295 	mmc_release_host(host);
2296 
2297  out:
2298 	if (host->caps & MMC_CAP_NEEDS_POLL)
2299 		mmc_schedule_delayed_work(&host->detect, HZ);
2300 }
2301 
2302 void mmc_start_host(struct mmc_host *host)
2303 {
2304 	host->f_init = max(min(freqs[0], host->f_max), host->f_min);
2305 	host->rescan_disable = 0;
2306 	host->ios.power_mode = MMC_POWER_UNDEFINED;
2307 
2308 	if (!(host->caps2 & MMC_CAP2_NO_PRESCAN_POWERUP)) {
2309 		mmc_claim_host(host);
2310 		mmc_power_up(host, host->ocr_avail);
2311 		mmc_release_host(host);
2312 	}
2313 
2314 	mmc_gpiod_request_cd_irq(host);
2315 	_mmc_detect_change(host, 0, false);
2316 }
2317 
2318 void mmc_stop_host(struct mmc_host *host)
2319 {
2320 	if (host->slot.cd_irq >= 0) {
2321 		mmc_gpio_set_cd_wake(host, false);
2322 		disable_irq(host->slot.cd_irq);
2323 	}
2324 
2325 	host->rescan_disable = 1;
2326 	cancel_delayed_work_sync(&host->detect);
2327 
2328 	/* clear pm flags now and let card drivers set them as needed */
2329 	host->pm_flags = 0;
2330 
2331 	mmc_bus_get(host);
2332 	if (host->bus_ops && !host->bus_dead) {
2333 		/* Calling bus_ops->remove() with a claimed host can deadlock */
2334 		host->bus_ops->remove(host);
2335 		mmc_claim_host(host);
2336 		mmc_detach_bus(host);
2337 		mmc_power_off(host);
2338 		mmc_release_host(host);
2339 		mmc_bus_put(host);
2340 		return;
2341 	}
2342 	mmc_bus_put(host);
2343 
2344 	mmc_claim_host(host);
2345 	mmc_power_off(host);
2346 	mmc_release_host(host);
2347 }
2348 
2349 #ifdef CONFIG_PM_SLEEP
2350 /* Do the card removal on suspend if card is assumed removeable
2351  * Do that in pm notifier while userspace isn't yet frozen, so we will be able
2352    to sync the card.
2353 */
2354 static int mmc_pm_notify(struct notifier_block *notify_block,
2355 			unsigned long mode, void *unused)
2356 {
2357 	struct mmc_host *host = container_of(
2358 		notify_block, struct mmc_host, pm_notify);
2359 	unsigned long flags;
2360 	int err = 0;
2361 
2362 	switch (mode) {
2363 	case PM_HIBERNATION_PREPARE:
2364 	case PM_SUSPEND_PREPARE:
2365 	case PM_RESTORE_PREPARE:
2366 		spin_lock_irqsave(&host->lock, flags);
2367 		host->rescan_disable = 1;
2368 		spin_unlock_irqrestore(&host->lock, flags);
2369 		cancel_delayed_work_sync(&host->detect);
2370 
2371 		if (!host->bus_ops)
2372 			break;
2373 
2374 		/* Validate prerequisites for suspend */
2375 		if (host->bus_ops->pre_suspend)
2376 			err = host->bus_ops->pre_suspend(host);
2377 		if (!err)
2378 			break;
2379 
2380 		if (!mmc_card_is_removable(host)) {
2381 			dev_warn(mmc_dev(host),
2382 				 "pre_suspend failed for non-removable host: "
2383 				 "%d\n", err);
2384 			/* Avoid removing non-removable hosts */
2385 			break;
2386 		}
2387 
2388 		/* Calling bus_ops->remove() with a claimed host can deadlock */
2389 		host->bus_ops->remove(host);
2390 		mmc_claim_host(host);
2391 		mmc_detach_bus(host);
2392 		mmc_power_off(host);
2393 		mmc_release_host(host);
2394 		host->pm_flags = 0;
2395 		break;
2396 
2397 	case PM_POST_SUSPEND:
2398 	case PM_POST_HIBERNATION:
2399 	case PM_POST_RESTORE:
2400 
2401 		spin_lock_irqsave(&host->lock, flags);
2402 		host->rescan_disable = 0;
2403 		spin_unlock_irqrestore(&host->lock, flags);
2404 		_mmc_detect_change(host, 0, false);
2405 
2406 	}
2407 
2408 	return 0;
2409 }
2410 
2411 void mmc_register_pm_notifier(struct mmc_host *host)
2412 {
2413 	host->pm_notify.notifier_call = mmc_pm_notify;
2414 	register_pm_notifier(&host->pm_notify);
2415 }
2416 
2417 void mmc_unregister_pm_notifier(struct mmc_host *host)
2418 {
2419 	unregister_pm_notifier(&host->pm_notify);
2420 }
2421 #endif
2422 
2423 static int __init mmc_init(void)
2424 {
2425 	int ret;
2426 
2427 	ret = mmc_register_bus();
2428 	if (ret)
2429 		return ret;
2430 
2431 	ret = mmc_register_host_class();
2432 	if (ret)
2433 		goto unregister_bus;
2434 
2435 	ret = sdio_register_bus();
2436 	if (ret)
2437 		goto unregister_host_class;
2438 
2439 	return 0;
2440 
2441 unregister_host_class:
2442 	mmc_unregister_host_class();
2443 unregister_bus:
2444 	mmc_unregister_bus();
2445 	return ret;
2446 }
2447 
2448 static void __exit mmc_exit(void)
2449 {
2450 	sdio_unregister_bus();
2451 	mmc_unregister_host_class();
2452 	mmc_unregister_bus();
2453 }
2454 
2455 subsys_initcall(mmc_init);
2456 module_exit(mmc_exit);
2457 
2458 MODULE_LICENSE("GPL");
2459