xref: /openbmc/linux/drivers/mmc/core/core.c (revision 3fc41476)
1 /*
2  *  linux/drivers/mmc/core/core.c
3  *
4  *  Copyright (C) 2003-2004 Russell King, All Rights Reserved.
5  *  SD support Copyright (C) 2004 Ian Molton, All Rights Reserved.
6  *  Copyright (C) 2005-2008 Pierre Ossman, All Rights Reserved.
7  *  MMCv4 support Copyright (C) 2006 Philip Langdale, All Rights Reserved.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/interrupt.h>
16 #include <linux/completion.h>
17 #include <linux/device.h>
18 #include <linux/delay.h>
19 #include <linux/pagemap.h>
20 #include <linux/err.h>
21 #include <linux/leds.h>
22 #include <linux/scatterlist.h>
23 #include <linux/log2.h>
24 #include <linux/pm_runtime.h>
25 #include <linux/pm_wakeup.h>
26 #include <linux/suspend.h>
27 #include <linux/fault-inject.h>
28 #include <linux/random.h>
29 #include <linux/slab.h>
30 #include <linux/of.h>
31 
32 #include <linux/mmc/card.h>
33 #include <linux/mmc/host.h>
34 #include <linux/mmc/mmc.h>
35 #include <linux/mmc/sd.h>
36 #include <linux/mmc/slot-gpio.h>
37 
38 #define CREATE_TRACE_POINTS
39 #include <trace/events/mmc.h>
40 
41 #include "core.h"
42 #include "card.h"
43 #include "bus.h"
44 #include "host.h"
45 #include "sdio_bus.h"
46 #include "pwrseq.h"
47 
48 #include "mmc_ops.h"
49 #include "sd_ops.h"
50 #include "sdio_ops.h"
51 
52 /* The max erase timeout, used when host->max_busy_timeout isn't specified */
53 #define MMC_ERASE_TIMEOUT_MS	(60 * 1000) /* 60 s */
54 #define SD_DISCARD_TIMEOUT_MS	(250)
55 
56 static const unsigned freqs[] = { 400000, 300000, 200000, 100000 };
57 
58 /*
59  * Enabling software CRCs on the data blocks can be a significant (30%)
60  * performance cost, and for other reasons may not always be desired.
61  * So we allow it it to be disabled.
62  */
63 bool use_spi_crc = 1;
64 module_param(use_spi_crc, bool, 0);
65 
66 static int mmc_schedule_delayed_work(struct delayed_work *work,
67 				     unsigned long delay)
68 {
69 	/*
70 	 * We use the system_freezable_wq, because of two reasons.
71 	 * First, it allows several works (not the same work item) to be
72 	 * executed simultaneously. Second, the queue becomes frozen when
73 	 * userspace becomes frozen during system PM.
74 	 */
75 	return queue_delayed_work(system_freezable_wq, work, delay);
76 }
77 
78 #ifdef CONFIG_FAIL_MMC_REQUEST
79 
80 /*
81  * Internal function. Inject random data errors.
82  * If mmc_data is NULL no errors are injected.
83  */
84 static void mmc_should_fail_request(struct mmc_host *host,
85 				    struct mmc_request *mrq)
86 {
87 	struct mmc_command *cmd = mrq->cmd;
88 	struct mmc_data *data = mrq->data;
89 	static const int data_errors[] = {
90 		-ETIMEDOUT,
91 		-EILSEQ,
92 		-EIO,
93 	};
94 
95 	if (!data)
96 		return;
97 
98 	if ((cmd && cmd->error) || data->error ||
99 	    !should_fail(&host->fail_mmc_request, data->blksz * data->blocks))
100 		return;
101 
102 	data->error = data_errors[prandom_u32() % ARRAY_SIZE(data_errors)];
103 	data->bytes_xfered = (prandom_u32() % (data->bytes_xfered >> 9)) << 9;
104 }
105 
106 #else /* CONFIG_FAIL_MMC_REQUEST */
107 
108 static inline void mmc_should_fail_request(struct mmc_host *host,
109 					   struct mmc_request *mrq)
110 {
111 }
112 
113 #endif /* CONFIG_FAIL_MMC_REQUEST */
114 
115 static inline void mmc_complete_cmd(struct mmc_request *mrq)
116 {
117 	if (mrq->cap_cmd_during_tfr && !completion_done(&mrq->cmd_completion))
118 		complete_all(&mrq->cmd_completion);
119 }
120 
121 void mmc_command_done(struct mmc_host *host, struct mmc_request *mrq)
122 {
123 	if (!mrq->cap_cmd_during_tfr)
124 		return;
125 
126 	mmc_complete_cmd(mrq);
127 
128 	pr_debug("%s: cmd done, tfr ongoing (CMD%u)\n",
129 		 mmc_hostname(host), mrq->cmd->opcode);
130 }
131 EXPORT_SYMBOL(mmc_command_done);
132 
133 /**
134  *	mmc_request_done - finish processing an MMC request
135  *	@host: MMC host which completed request
136  *	@mrq: MMC request which request
137  *
138  *	MMC drivers should call this function when they have completed
139  *	their processing of a request.
140  */
141 void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
142 {
143 	struct mmc_command *cmd = mrq->cmd;
144 	int err = cmd->error;
145 
146 	/* Flag re-tuning needed on CRC errors */
147 	if ((cmd->opcode != MMC_SEND_TUNING_BLOCK &&
148 	    cmd->opcode != MMC_SEND_TUNING_BLOCK_HS200) &&
149 	    (err == -EILSEQ || (mrq->sbc && mrq->sbc->error == -EILSEQ) ||
150 	    (mrq->data && mrq->data->error == -EILSEQ) ||
151 	    (mrq->stop && mrq->stop->error == -EILSEQ)))
152 		mmc_retune_needed(host);
153 
154 	if (err && cmd->retries && mmc_host_is_spi(host)) {
155 		if (cmd->resp[0] & R1_SPI_ILLEGAL_COMMAND)
156 			cmd->retries = 0;
157 	}
158 
159 	if (host->ongoing_mrq == mrq)
160 		host->ongoing_mrq = NULL;
161 
162 	mmc_complete_cmd(mrq);
163 
164 	trace_mmc_request_done(host, mrq);
165 
166 	/*
167 	 * We list various conditions for the command to be considered
168 	 * properly done:
169 	 *
170 	 * - There was no error, OK fine then
171 	 * - We are not doing some kind of retry
172 	 * - The card was removed (...so just complete everything no matter
173 	 *   if there are errors or retries)
174 	 */
175 	if (!err || !cmd->retries || mmc_card_removed(host->card)) {
176 		mmc_should_fail_request(host, mrq);
177 
178 		if (!host->ongoing_mrq)
179 			led_trigger_event(host->led, LED_OFF);
180 
181 		if (mrq->sbc) {
182 			pr_debug("%s: req done <CMD%u>: %d: %08x %08x %08x %08x\n",
183 				mmc_hostname(host), mrq->sbc->opcode,
184 				mrq->sbc->error,
185 				mrq->sbc->resp[0], mrq->sbc->resp[1],
186 				mrq->sbc->resp[2], mrq->sbc->resp[3]);
187 		}
188 
189 		pr_debug("%s: req done (CMD%u): %d: %08x %08x %08x %08x\n",
190 			mmc_hostname(host), cmd->opcode, err,
191 			cmd->resp[0], cmd->resp[1],
192 			cmd->resp[2], cmd->resp[3]);
193 
194 		if (mrq->data) {
195 			pr_debug("%s:     %d bytes transferred: %d\n",
196 				mmc_hostname(host),
197 				mrq->data->bytes_xfered, mrq->data->error);
198 		}
199 
200 		if (mrq->stop) {
201 			pr_debug("%s:     (CMD%u): %d: %08x %08x %08x %08x\n",
202 				mmc_hostname(host), mrq->stop->opcode,
203 				mrq->stop->error,
204 				mrq->stop->resp[0], mrq->stop->resp[1],
205 				mrq->stop->resp[2], mrq->stop->resp[3]);
206 		}
207 	}
208 	/*
209 	 * Request starter must handle retries - see
210 	 * mmc_wait_for_req_done().
211 	 */
212 	if (mrq->done)
213 		mrq->done(mrq);
214 }
215 
216 EXPORT_SYMBOL(mmc_request_done);
217 
218 static void __mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
219 {
220 	int err;
221 
222 	/* Assumes host controller has been runtime resumed by mmc_claim_host */
223 	err = mmc_retune(host);
224 	if (err) {
225 		mrq->cmd->error = err;
226 		mmc_request_done(host, mrq);
227 		return;
228 	}
229 
230 	/*
231 	 * For sdio rw commands we must wait for card busy otherwise some
232 	 * sdio devices won't work properly.
233 	 * And bypass I/O abort, reset and bus suspend operations.
234 	 */
235 	if (sdio_is_io_busy(mrq->cmd->opcode, mrq->cmd->arg) &&
236 	    host->ops->card_busy) {
237 		int tries = 500; /* Wait aprox 500ms at maximum */
238 
239 		while (host->ops->card_busy(host) && --tries)
240 			mmc_delay(1);
241 
242 		if (tries == 0) {
243 			mrq->cmd->error = -EBUSY;
244 			mmc_request_done(host, mrq);
245 			return;
246 		}
247 	}
248 
249 	if (mrq->cap_cmd_during_tfr) {
250 		host->ongoing_mrq = mrq;
251 		/*
252 		 * Retry path could come through here without having waiting on
253 		 * cmd_completion, so ensure it is reinitialised.
254 		 */
255 		reinit_completion(&mrq->cmd_completion);
256 	}
257 
258 	trace_mmc_request_start(host, mrq);
259 
260 	if (host->cqe_on)
261 		host->cqe_ops->cqe_off(host);
262 
263 	host->ops->request(host, mrq);
264 }
265 
266 static void mmc_mrq_pr_debug(struct mmc_host *host, struct mmc_request *mrq,
267 			     bool cqe)
268 {
269 	if (mrq->sbc) {
270 		pr_debug("<%s: starting CMD%u arg %08x flags %08x>\n",
271 			 mmc_hostname(host), mrq->sbc->opcode,
272 			 mrq->sbc->arg, mrq->sbc->flags);
273 	}
274 
275 	if (mrq->cmd) {
276 		pr_debug("%s: starting %sCMD%u arg %08x flags %08x\n",
277 			 mmc_hostname(host), cqe ? "CQE direct " : "",
278 			 mrq->cmd->opcode, mrq->cmd->arg, mrq->cmd->flags);
279 	} else if (cqe) {
280 		pr_debug("%s: starting CQE transfer for tag %d blkaddr %u\n",
281 			 mmc_hostname(host), mrq->tag, mrq->data->blk_addr);
282 	}
283 
284 	if (mrq->data) {
285 		pr_debug("%s:     blksz %d blocks %d flags %08x "
286 			"tsac %d ms nsac %d\n",
287 			mmc_hostname(host), mrq->data->blksz,
288 			mrq->data->blocks, mrq->data->flags,
289 			mrq->data->timeout_ns / 1000000,
290 			mrq->data->timeout_clks);
291 	}
292 
293 	if (mrq->stop) {
294 		pr_debug("%s:     CMD%u arg %08x flags %08x\n",
295 			 mmc_hostname(host), mrq->stop->opcode,
296 			 mrq->stop->arg, mrq->stop->flags);
297 	}
298 }
299 
300 static int mmc_mrq_prep(struct mmc_host *host, struct mmc_request *mrq)
301 {
302 	unsigned int i, sz = 0;
303 	struct scatterlist *sg;
304 
305 	if (mrq->cmd) {
306 		mrq->cmd->error = 0;
307 		mrq->cmd->mrq = mrq;
308 		mrq->cmd->data = mrq->data;
309 	}
310 	if (mrq->sbc) {
311 		mrq->sbc->error = 0;
312 		mrq->sbc->mrq = mrq;
313 	}
314 	if (mrq->data) {
315 		if (mrq->data->blksz > host->max_blk_size ||
316 		    mrq->data->blocks > host->max_blk_count ||
317 		    mrq->data->blocks * mrq->data->blksz > host->max_req_size)
318 			return -EINVAL;
319 
320 		for_each_sg(mrq->data->sg, sg, mrq->data->sg_len, i)
321 			sz += sg->length;
322 		if (sz != mrq->data->blocks * mrq->data->blksz)
323 			return -EINVAL;
324 
325 		mrq->data->error = 0;
326 		mrq->data->mrq = mrq;
327 		if (mrq->stop) {
328 			mrq->data->stop = mrq->stop;
329 			mrq->stop->error = 0;
330 			mrq->stop->mrq = mrq;
331 		}
332 	}
333 
334 	return 0;
335 }
336 
337 int mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
338 {
339 	int err;
340 
341 	init_completion(&mrq->cmd_completion);
342 
343 	mmc_retune_hold(host);
344 
345 	if (mmc_card_removed(host->card))
346 		return -ENOMEDIUM;
347 
348 	mmc_mrq_pr_debug(host, mrq, false);
349 
350 	WARN_ON(!host->claimed);
351 
352 	err = mmc_mrq_prep(host, mrq);
353 	if (err)
354 		return err;
355 
356 	led_trigger_event(host->led, LED_FULL);
357 	__mmc_start_request(host, mrq);
358 
359 	return 0;
360 }
361 EXPORT_SYMBOL(mmc_start_request);
362 
363 static void mmc_wait_done(struct mmc_request *mrq)
364 {
365 	complete(&mrq->completion);
366 }
367 
368 static inline void mmc_wait_ongoing_tfr_cmd(struct mmc_host *host)
369 {
370 	struct mmc_request *ongoing_mrq = READ_ONCE(host->ongoing_mrq);
371 
372 	/*
373 	 * If there is an ongoing transfer, wait for the command line to become
374 	 * available.
375 	 */
376 	if (ongoing_mrq && !completion_done(&ongoing_mrq->cmd_completion))
377 		wait_for_completion(&ongoing_mrq->cmd_completion);
378 }
379 
380 static int __mmc_start_req(struct mmc_host *host, struct mmc_request *mrq)
381 {
382 	int err;
383 
384 	mmc_wait_ongoing_tfr_cmd(host);
385 
386 	init_completion(&mrq->completion);
387 	mrq->done = mmc_wait_done;
388 
389 	err = mmc_start_request(host, mrq);
390 	if (err) {
391 		mrq->cmd->error = err;
392 		mmc_complete_cmd(mrq);
393 		complete(&mrq->completion);
394 	}
395 
396 	return err;
397 }
398 
399 void mmc_wait_for_req_done(struct mmc_host *host, struct mmc_request *mrq)
400 {
401 	struct mmc_command *cmd;
402 
403 	while (1) {
404 		wait_for_completion(&mrq->completion);
405 
406 		cmd = mrq->cmd;
407 
408 		/*
409 		 * If host has timed out waiting for the sanitize
410 		 * to complete, card might be still in programming state
411 		 * so let's try to bring the card out of programming
412 		 * state.
413 		 */
414 		if (cmd->sanitize_busy && cmd->error == -ETIMEDOUT) {
415 			if (!mmc_interrupt_hpi(host->card)) {
416 				pr_warn("%s: %s: Interrupted sanitize\n",
417 					mmc_hostname(host), __func__);
418 				cmd->error = 0;
419 				break;
420 			} else {
421 				pr_err("%s: %s: Failed to interrupt sanitize\n",
422 				       mmc_hostname(host), __func__);
423 			}
424 		}
425 		if (!cmd->error || !cmd->retries ||
426 		    mmc_card_removed(host->card))
427 			break;
428 
429 		mmc_retune_recheck(host);
430 
431 		pr_debug("%s: req failed (CMD%u): %d, retrying...\n",
432 			 mmc_hostname(host), cmd->opcode, cmd->error);
433 		cmd->retries--;
434 		cmd->error = 0;
435 		__mmc_start_request(host, mrq);
436 	}
437 
438 	mmc_retune_release(host);
439 }
440 EXPORT_SYMBOL(mmc_wait_for_req_done);
441 
442 /*
443  * mmc_cqe_start_req - Start a CQE request.
444  * @host: MMC host to start the request
445  * @mrq: request to start
446  *
447  * Start the request, re-tuning if needed and it is possible. Returns an error
448  * code if the request fails to start or -EBUSY if CQE is busy.
449  */
450 int mmc_cqe_start_req(struct mmc_host *host, struct mmc_request *mrq)
451 {
452 	int err;
453 
454 	/*
455 	 * CQE cannot process re-tuning commands. Caller must hold retuning
456 	 * while CQE is in use.  Re-tuning can happen here only when CQE has no
457 	 * active requests i.e. this is the first.  Note, re-tuning will call
458 	 * ->cqe_off().
459 	 */
460 	err = mmc_retune(host);
461 	if (err)
462 		goto out_err;
463 
464 	mrq->host = host;
465 
466 	mmc_mrq_pr_debug(host, mrq, true);
467 
468 	err = mmc_mrq_prep(host, mrq);
469 	if (err)
470 		goto out_err;
471 
472 	err = host->cqe_ops->cqe_request(host, mrq);
473 	if (err)
474 		goto out_err;
475 
476 	trace_mmc_request_start(host, mrq);
477 
478 	return 0;
479 
480 out_err:
481 	if (mrq->cmd) {
482 		pr_debug("%s: failed to start CQE direct CMD%u, error %d\n",
483 			 mmc_hostname(host), mrq->cmd->opcode, err);
484 	} else {
485 		pr_debug("%s: failed to start CQE transfer for tag %d, error %d\n",
486 			 mmc_hostname(host), mrq->tag, err);
487 	}
488 	return err;
489 }
490 EXPORT_SYMBOL(mmc_cqe_start_req);
491 
492 /**
493  *	mmc_cqe_request_done - CQE has finished processing an MMC request
494  *	@host: MMC host which completed request
495  *	@mrq: MMC request which completed
496  *
497  *	CQE drivers should call this function when they have completed
498  *	their processing of a request.
499  */
500 void mmc_cqe_request_done(struct mmc_host *host, struct mmc_request *mrq)
501 {
502 	mmc_should_fail_request(host, mrq);
503 
504 	/* Flag re-tuning needed on CRC errors */
505 	if ((mrq->cmd && mrq->cmd->error == -EILSEQ) ||
506 	    (mrq->data && mrq->data->error == -EILSEQ))
507 		mmc_retune_needed(host);
508 
509 	trace_mmc_request_done(host, mrq);
510 
511 	if (mrq->cmd) {
512 		pr_debug("%s: CQE req done (direct CMD%u): %d\n",
513 			 mmc_hostname(host), mrq->cmd->opcode, mrq->cmd->error);
514 	} else {
515 		pr_debug("%s: CQE transfer done tag %d\n",
516 			 mmc_hostname(host), mrq->tag);
517 	}
518 
519 	if (mrq->data) {
520 		pr_debug("%s:     %d bytes transferred: %d\n",
521 			 mmc_hostname(host),
522 			 mrq->data->bytes_xfered, mrq->data->error);
523 	}
524 
525 	mrq->done(mrq);
526 }
527 EXPORT_SYMBOL(mmc_cqe_request_done);
528 
529 /**
530  *	mmc_cqe_post_req - CQE post process of a completed MMC request
531  *	@host: MMC host
532  *	@mrq: MMC request to be processed
533  */
534 void mmc_cqe_post_req(struct mmc_host *host, struct mmc_request *mrq)
535 {
536 	if (host->cqe_ops->cqe_post_req)
537 		host->cqe_ops->cqe_post_req(host, mrq);
538 }
539 EXPORT_SYMBOL(mmc_cqe_post_req);
540 
541 /* Arbitrary 1 second timeout */
542 #define MMC_CQE_RECOVERY_TIMEOUT	1000
543 
544 /*
545  * mmc_cqe_recovery - Recover from CQE errors.
546  * @host: MMC host to recover
547  *
548  * Recovery consists of stopping CQE, stopping eMMC, discarding the queue in
549  * in eMMC, and discarding the queue in CQE. CQE must call
550  * mmc_cqe_request_done() on all requests. An error is returned if the eMMC
551  * fails to discard its queue.
552  */
553 int mmc_cqe_recovery(struct mmc_host *host)
554 {
555 	struct mmc_command cmd;
556 	int err;
557 
558 	mmc_retune_hold_now(host);
559 
560 	/*
561 	 * Recovery is expected seldom, if at all, but it reduces performance,
562 	 * so make sure it is not completely silent.
563 	 */
564 	pr_warn("%s: running CQE recovery\n", mmc_hostname(host));
565 
566 	host->cqe_ops->cqe_recovery_start(host);
567 
568 	memset(&cmd, 0, sizeof(cmd));
569 	cmd.opcode       = MMC_STOP_TRANSMISSION,
570 	cmd.flags        = MMC_RSP_R1B | MMC_CMD_AC,
571 	cmd.flags       &= ~MMC_RSP_CRC; /* Ignore CRC */
572 	cmd.busy_timeout = MMC_CQE_RECOVERY_TIMEOUT,
573 	mmc_wait_for_cmd(host, &cmd, 0);
574 
575 	memset(&cmd, 0, sizeof(cmd));
576 	cmd.opcode       = MMC_CMDQ_TASK_MGMT;
577 	cmd.arg          = 1; /* Discard entire queue */
578 	cmd.flags        = MMC_RSP_R1B | MMC_CMD_AC;
579 	cmd.flags       &= ~MMC_RSP_CRC; /* Ignore CRC */
580 	cmd.busy_timeout = MMC_CQE_RECOVERY_TIMEOUT,
581 	err = mmc_wait_for_cmd(host, &cmd, 0);
582 
583 	host->cqe_ops->cqe_recovery_finish(host);
584 
585 	mmc_retune_release(host);
586 
587 	return err;
588 }
589 EXPORT_SYMBOL(mmc_cqe_recovery);
590 
591 /**
592  *	mmc_is_req_done - Determine if a 'cap_cmd_during_tfr' request is done
593  *	@host: MMC host
594  *	@mrq: MMC request
595  *
596  *	mmc_is_req_done() is used with requests that have
597  *	mrq->cap_cmd_during_tfr = true. mmc_is_req_done() must be called after
598  *	starting a request and before waiting for it to complete. That is,
599  *	either in between calls to mmc_start_req(), or after mmc_wait_for_req()
600  *	and before mmc_wait_for_req_done(). If it is called at other times the
601  *	result is not meaningful.
602  */
603 bool mmc_is_req_done(struct mmc_host *host, struct mmc_request *mrq)
604 {
605 	return completion_done(&mrq->completion);
606 }
607 EXPORT_SYMBOL(mmc_is_req_done);
608 
609 /**
610  *	mmc_wait_for_req - start a request and wait for completion
611  *	@host: MMC host to start command
612  *	@mrq: MMC request to start
613  *
614  *	Start a new MMC custom command request for a host, and wait
615  *	for the command to complete. In the case of 'cap_cmd_during_tfr'
616  *	requests, the transfer is ongoing and the caller can issue further
617  *	commands that do not use the data lines, and then wait by calling
618  *	mmc_wait_for_req_done().
619  *	Does not attempt to parse the response.
620  */
621 void mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq)
622 {
623 	__mmc_start_req(host, mrq);
624 
625 	if (!mrq->cap_cmd_during_tfr)
626 		mmc_wait_for_req_done(host, mrq);
627 }
628 EXPORT_SYMBOL(mmc_wait_for_req);
629 
630 /**
631  *	mmc_wait_for_cmd - start a command and wait for completion
632  *	@host: MMC host to start command
633  *	@cmd: MMC command to start
634  *	@retries: maximum number of retries
635  *
636  *	Start a new MMC command for a host, and wait for the command
637  *	to complete.  Return any error that occurred while the command
638  *	was executing.  Do not attempt to parse the response.
639  */
640 int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries)
641 {
642 	struct mmc_request mrq = {};
643 
644 	WARN_ON(!host->claimed);
645 
646 	memset(cmd->resp, 0, sizeof(cmd->resp));
647 	cmd->retries = retries;
648 
649 	mrq.cmd = cmd;
650 	cmd->data = NULL;
651 
652 	mmc_wait_for_req(host, &mrq);
653 
654 	return cmd->error;
655 }
656 
657 EXPORT_SYMBOL(mmc_wait_for_cmd);
658 
659 /**
660  *	mmc_set_data_timeout - set the timeout for a data command
661  *	@data: data phase for command
662  *	@card: the MMC card associated with the data transfer
663  *
664  *	Computes the data timeout parameters according to the
665  *	correct algorithm given the card type.
666  */
667 void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card)
668 {
669 	unsigned int mult;
670 
671 	/*
672 	 * SDIO cards only define an upper 1 s limit on access.
673 	 */
674 	if (mmc_card_sdio(card)) {
675 		data->timeout_ns = 1000000000;
676 		data->timeout_clks = 0;
677 		return;
678 	}
679 
680 	/*
681 	 * SD cards use a 100 multiplier rather than 10
682 	 */
683 	mult = mmc_card_sd(card) ? 100 : 10;
684 
685 	/*
686 	 * Scale up the multiplier (and therefore the timeout) by
687 	 * the r2w factor for writes.
688 	 */
689 	if (data->flags & MMC_DATA_WRITE)
690 		mult <<= card->csd.r2w_factor;
691 
692 	data->timeout_ns = card->csd.taac_ns * mult;
693 	data->timeout_clks = card->csd.taac_clks * mult;
694 
695 	/*
696 	 * SD cards also have an upper limit on the timeout.
697 	 */
698 	if (mmc_card_sd(card)) {
699 		unsigned int timeout_us, limit_us;
700 
701 		timeout_us = data->timeout_ns / 1000;
702 		if (card->host->ios.clock)
703 			timeout_us += data->timeout_clks * 1000 /
704 				(card->host->ios.clock / 1000);
705 
706 		if (data->flags & MMC_DATA_WRITE)
707 			/*
708 			 * The MMC spec "It is strongly recommended
709 			 * for hosts to implement more than 500ms
710 			 * timeout value even if the card indicates
711 			 * the 250ms maximum busy length."  Even the
712 			 * previous value of 300ms is known to be
713 			 * insufficient for some cards.
714 			 */
715 			limit_us = 3000000;
716 		else
717 			limit_us = 100000;
718 
719 		/*
720 		 * SDHC cards always use these fixed values.
721 		 */
722 		if (timeout_us > limit_us) {
723 			data->timeout_ns = limit_us * 1000;
724 			data->timeout_clks = 0;
725 		}
726 
727 		/* assign limit value if invalid */
728 		if (timeout_us == 0)
729 			data->timeout_ns = limit_us * 1000;
730 	}
731 
732 	/*
733 	 * Some cards require longer data read timeout than indicated in CSD.
734 	 * Address this by setting the read timeout to a "reasonably high"
735 	 * value. For the cards tested, 600ms has proven enough. If necessary,
736 	 * this value can be increased if other problematic cards require this.
737 	 */
738 	if (mmc_card_long_read_time(card) && data->flags & MMC_DATA_READ) {
739 		data->timeout_ns = 600000000;
740 		data->timeout_clks = 0;
741 	}
742 
743 	/*
744 	 * Some cards need very high timeouts if driven in SPI mode.
745 	 * The worst observed timeout was 900ms after writing a
746 	 * continuous stream of data until the internal logic
747 	 * overflowed.
748 	 */
749 	if (mmc_host_is_spi(card->host)) {
750 		if (data->flags & MMC_DATA_WRITE) {
751 			if (data->timeout_ns < 1000000000)
752 				data->timeout_ns = 1000000000;	/* 1s */
753 		} else {
754 			if (data->timeout_ns < 100000000)
755 				data->timeout_ns =  100000000;	/* 100ms */
756 		}
757 	}
758 }
759 EXPORT_SYMBOL(mmc_set_data_timeout);
760 
761 /*
762  * Allow claiming an already claimed host if the context is the same or there is
763  * no context but the task is the same.
764  */
765 static inline bool mmc_ctx_matches(struct mmc_host *host, struct mmc_ctx *ctx,
766 				   struct task_struct *task)
767 {
768 	return host->claimer == ctx ||
769 	       (!ctx && task && host->claimer->task == task);
770 }
771 
772 static inline void mmc_ctx_set_claimer(struct mmc_host *host,
773 				       struct mmc_ctx *ctx,
774 				       struct task_struct *task)
775 {
776 	if (!host->claimer) {
777 		if (ctx)
778 			host->claimer = ctx;
779 		else
780 			host->claimer = &host->default_ctx;
781 	}
782 	if (task)
783 		host->claimer->task = task;
784 }
785 
786 /**
787  *	__mmc_claim_host - exclusively claim a host
788  *	@host: mmc host to claim
789  *	@ctx: context that claims the host or NULL in which case the default
790  *	context will be used
791  *	@abort: whether or not the operation should be aborted
792  *
793  *	Claim a host for a set of operations.  If @abort is non null and
794  *	dereference a non-zero value then this will return prematurely with
795  *	that non-zero value without acquiring the lock.  Returns zero
796  *	with the lock held otherwise.
797  */
798 int __mmc_claim_host(struct mmc_host *host, struct mmc_ctx *ctx,
799 		     atomic_t *abort)
800 {
801 	struct task_struct *task = ctx ? NULL : current;
802 	DECLARE_WAITQUEUE(wait, current);
803 	unsigned long flags;
804 	int stop;
805 	bool pm = false;
806 
807 	might_sleep();
808 
809 	add_wait_queue(&host->wq, &wait);
810 	spin_lock_irqsave(&host->lock, flags);
811 	while (1) {
812 		set_current_state(TASK_UNINTERRUPTIBLE);
813 		stop = abort ? atomic_read(abort) : 0;
814 		if (stop || !host->claimed || mmc_ctx_matches(host, ctx, task))
815 			break;
816 		spin_unlock_irqrestore(&host->lock, flags);
817 		schedule();
818 		spin_lock_irqsave(&host->lock, flags);
819 	}
820 	set_current_state(TASK_RUNNING);
821 	if (!stop) {
822 		host->claimed = 1;
823 		mmc_ctx_set_claimer(host, ctx, task);
824 		host->claim_cnt += 1;
825 		if (host->claim_cnt == 1)
826 			pm = true;
827 	} else
828 		wake_up(&host->wq);
829 	spin_unlock_irqrestore(&host->lock, flags);
830 	remove_wait_queue(&host->wq, &wait);
831 
832 	if (pm)
833 		pm_runtime_get_sync(mmc_dev(host));
834 
835 	return stop;
836 }
837 EXPORT_SYMBOL(__mmc_claim_host);
838 
839 /**
840  *	mmc_release_host - release a host
841  *	@host: mmc host to release
842  *
843  *	Release a MMC host, allowing others to claim the host
844  *	for their operations.
845  */
846 void mmc_release_host(struct mmc_host *host)
847 {
848 	unsigned long flags;
849 
850 	WARN_ON(!host->claimed);
851 
852 	spin_lock_irqsave(&host->lock, flags);
853 	if (--host->claim_cnt) {
854 		/* Release for nested claim */
855 		spin_unlock_irqrestore(&host->lock, flags);
856 	} else {
857 		host->claimed = 0;
858 		host->claimer->task = NULL;
859 		host->claimer = NULL;
860 		spin_unlock_irqrestore(&host->lock, flags);
861 		wake_up(&host->wq);
862 		pm_runtime_mark_last_busy(mmc_dev(host));
863 		if (host->caps & MMC_CAP_SYNC_RUNTIME_PM)
864 			pm_runtime_put_sync_suspend(mmc_dev(host));
865 		else
866 			pm_runtime_put_autosuspend(mmc_dev(host));
867 	}
868 }
869 EXPORT_SYMBOL(mmc_release_host);
870 
871 /*
872  * This is a helper function, which fetches a runtime pm reference for the
873  * card device and also claims the host.
874  */
875 void mmc_get_card(struct mmc_card *card, struct mmc_ctx *ctx)
876 {
877 	pm_runtime_get_sync(&card->dev);
878 	__mmc_claim_host(card->host, ctx, NULL);
879 }
880 EXPORT_SYMBOL(mmc_get_card);
881 
882 /*
883  * This is a helper function, which releases the host and drops the runtime
884  * pm reference for the card device.
885  */
886 void mmc_put_card(struct mmc_card *card, struct mmc_ctx *ctx)
887 {
888 	struct mmc_host *host = card->host;
889 
890 	WARN_ON(ctx && host->claimer != ctx);
891 
892 	mmc_release_host(host);
893 	pm_runtime_mark_last_busy(&card->dev);
894 	pm_runtime_put_autosuspend(&card->dev);
895 }
896 EXPORT_SYMBOL(mmc_put_card);
897 
898 /*
899  * Internal function that does the actual ios call to the host driver,
900  * optionally printing some debug output.
901  */
902 static inline void mmc_set_ios(struct mmc_host *host)
903 {
904 	struct mmc_ios *ios = &host->ios;
905 
906 	pr_debug("%s: clock %uHz busmode %u powermode %u cs %u Vdd %u "
907 		"width %u timing %u\n",
908 		 mmc_hostname(host), ios->clock, ios->bus_mode,
909 		 ios->power_mode, ios->chip_select, ios->vdd,
910 		 1 << ios->bus_width, ios->timing);
911 
912 	host->ops->set_ios(host, ios);
913 }
914 
915 /*
916  * Control chip select pin on a host.
917  */
918 void mmc_set_chip_select(struct mmc_host *host, int mode)
919 {
920 	host->ios.chip_select = mode;
921 	mmc_set_ios(host);
922 }
923 
924 /*
925  * Sets the host clock to the highest possible frequency that
926  * is below "hz".
927  */
928 void mmc_set_clock(struct mmc_host *host, unsigned int hz)
929 {
930 	WARN_ON(hz && hz < host->f_min);
931 
932 	if (hz > host->f_max)
933 		hz = host->f_max;
934 
935 	host->ios.clock = hz;
936 	mmc_set_ios(host);
937 }
938 
939 int mmc_execute_tuning(struct mmc_card *card)
940 {
941 	struct mmc_host *host = card->host;
942 	u32 opcode;
943 	int err;
944 
945 	if (!host->ops->execute_tuning)
946 		return 0;
947 
948 	if (host->cqe_on)
949 		host->cqe_ops->cqe_off(host);
950 
951 	if (mmc_card_mmc(card))
952 		opcode = MMC_SEND_TUNING_BLOCK_HS200;
953 	else
954 		opcode = MMC_SEND_TUNING_BLOCK;
955 
956 	err = host->ops->execute_tuning(host, opcode);
957 
958 	if (err)
959 		pr_err("%s: tuning execution failed: %d\n",
960 			mmc_hostname(host), err);
961 	else
962 		mmc_retune_enable(host);
963 
964 	return err;
965 }
966 
967 /*
968  * Change the bus mode (open drain/push-pull) of a host.
969  */
970 void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode)
971 {
972 	host->ios.bus_mode = mode;
973 	mmc_set_ios(host);
974 }
975 
976 /*
977  * Change data bus width of a host.
978  */
979 void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
980 {
981 	host->ios.bus_width = width;
982 	mmc_set_ios(host);
983 }
984 
985 /*
986  * Set initial state after a power cycle or a hw_reset.
987  */
988 void mmc_set_initial_state(struct mmc_host *host)
989 {
990 	if (host->cqe_on)
991 		host->cqe_ops->cqe_off(host);
992 
993 	mmc_retune_disable(host);
994 
995 	if (mmc_host_is_spi(host))
996 		host->ios.chip_select = MMC_CS_HIGH;
997 	else
998 		host->ios.chip_select = MMC_CS_DONTCARE;
999 	host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
1000 	host->ios.bus_width = MMC_BUS_WIDTH_1;
1001 	host->ios.timing = MMC_TIMING_LEGACY;
1002 	host->ios.drv_type = 0;
1003 	host->ios.enhanced_strobe = false;
1004 
1005 	/*
1006 	 * Make sure we are in non-enhanced strobe mode before we
1007 	 * actually enable it in ext_csd.
1008 	 */
1009 	if ((host->caps2 & MMC_CAP2_HS400_ES) &&
1010 	     host->ops->hs400_enhanced_strobe)
1011 		host->ops->hs400_enhanced_strobe(host, &host->ios);
1012 
1013 	mmc_set_ios(host);
1014 }
1015 
1016 /**
1017  * mmc_vdd_to_ocrbitnum - Convert a voltage to the OCR bit number
1018  * @vdd:	voltage (mV)
1019  * @low_bits:	prefer low bits in boundary cases
1020  *
1021  * This function returns the OCR bit number according to the provided @vdd
1022  * value. If conversion is not possible a negative errno value returned.
1023  *
1024  * Depending on the @low_bits flag the function prefers low or high OCR bits
1025  * on boundary voltages. For example,
1026  * with @low_bits = true, 3300 mV translates to ilog2(MMC_VDD_32_33);
1027  * with @low_bits = false, 3300 mV translates to ilog2(MMC_VDD_33_34);
1028  *
1029  * Any value in the [1951:1999] range translates to the ilog2(MMC_VDD_20_21).
1030  */
1031 static int mmc_vdd_to_ocrbitnum(int vdd, bool low_bits)
1032 {
1033 	const int max_bit = ilog2(MMC_VDD_35_36);
1034 	int bit;
1035 
1036 	if (vdd < 1650 || vdd > 3600)
1037 		return -EINVAL;
1038 
1039 	if (vdd >= 1650 && vdd <= 1950)
1040 		return ilog2(MMC_VDD_165_195);
1041 
1042 	if (low_bits)
1043 		vdd -= 1;
1044 
1045 	/* Base 2000 mV, step 100 mV, bit's base 8. */
1046 	bit = (vdd - 2000) / 100 + 8;
1047 	if (bit > max_bit)
1048 		return max_bit;
1049 	return bit;
1050 }
1051 
1052 /**
1053  * mmc_vddrange_to_ocrmask - Convert a voltage range to the OCR mask
1054  * @vdd_min:	minimum voltage value (mV)
1055  * @vdd_max:	maximum voltage value (mV)
1056  *
1057  * This function returns the OCR mask bits according to the provided @vdd_min
1058  * and @vdd_max values. If conversion is not possible the function returns 0.
1059  *
1060  * Notes wrt boundary cases:
1061  * This function sets the OCR bits for all boundary voltages, for example
1062  * [3300:3400] range is translated to MMC_VDD_32_33 | MMC_VDD_33_34 |
1063  * MMC_VDD_34_35 mask.
1064  */
1065 u32 mmc_vddrange_to_ocrmask(int vdd_min, int vdd_max)
1066 {
1067 	u32 mask = 0;
1068 
1069 	if (vdd_max < vdd_min)
1070 		return 0;
1071 
1072 	/* Prefer high bits for the boundary vdd_max values. */
1073 	vdd_max = mmc_vdd_to_ocrbitnum(vdd_max, false);
1074 	if (vdd_max < 0)
1075 		return 0;
1076 
1077 	/* Prefer low bits for the boundary vdd_min values. */
1078 	vdd_min = mmc_vdd_to_ocrbitnum(vdd_min, true);
1079 	if (vdd_min < 0)
1080 		return 0;
1081 
1082 	/* Fill the mask, from max bit to min bit. */
1083 	while (vdd_max >= vdd_min)
1084 		mask |= 1 << vdd_max--;
1085 
1086 	return mask;
1087 }
1088 
1089 static int mmc_of_get_func_num(struct device_node *node)
1090 {
1091 	u32 reg;
1092 	int ret;
1093 
1094 	ret = of_property_read_u32(node, "reg", &reg);
1095 	if (ret < 0)
1096 		return ret;
1097 
1098 	return reg;
1099 }
1100 
1101 struct device_node *mmc_of_find_child_device(struct mmc_host *host,
1102 		unsigned func_num)
1103 {
1104 	struct device_node *node;
1105 
1106 	if (!host->parent || !host->parent->of_node)
1107 		return NULL;
1108 
1109 	for_each_child_of_node(host->parent->of_node, node) {
1110 		if (mmc_of_get_func_num(node) == func_num)
1111 			return node;
1112 	}
1113 
1114 	return NULL;
1115 }
1116 
1117 /*
1118  * Mask off any voltages we don't support and select
1119  * the lowest voltage
1120  */
1121 u32 mmc_select_voltage(struct mmc_host *host, u32 ocr)
1122 {
1123 	int bit;
1124 
1125 	/*
1126 	 * Sanity check the voltages that the card claims to
1127 	 * support.
1128 	 */
1129 	if (ocr & 0x7F) {
1130 		dev_warn(mmc_dev(host),
1131 		"card claims to support voltages below defined range\n");
1132 		ocr &= ~0x7F;
1133 	}
1134 
1135 	ocr &= host->ocr_avail;
1136 	if (!ocr) {
1137 		dev_warn(mmc_dev(host), "no support for card's volts\n");
1138 		return 0;
1139 	}
1140 
1141 	if (host->caps2 & MMC_CAP2_FULL_PWR_CYCLE) {
1142 		bit = ffs(ocr) - 1;
1143 		ocr &= 3 << bit;
1144 		mmc_power_cycle(host, ocr);
1145 	} else {
1146 		bit = fls(ocr) - 1;
1147 		ocr &= 3 << bit;
1148 		if (bit != host->ios.vdd)
1149 			dev_warn(mmc_dev(host), "exceeding card's volts\n");
1150 	}
1151 
1152 	return ocr;
1153 }
1154 
1155 int mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage)
1156 {
1157 	int err = 0;
1158 	int old_signal_voltage = host->ios.signal_voltage;
1159 
1160 	host->ios.signal_voltage = signal_voltage;
1161 	if (host->ops->start_signal_voltage_switch)
1162 		err = host->ops->start_signal_voltage_switch(host, &host->ios);
1163 
1164 	if (err)
1165 		host->ios.signal_voltage = old_signal_voltage;
1166 
1167 	return err;
1168 
1169 }
1170 
1171 void mmc_set_initial_signal_voltage(struct mmc_host *host)
1172 {
1173 	/* Try to set signal voltage to 3.3V but fall back to 1.8v or 1.2v */
1174 	if (!mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330))
1175 		dev_dbg(mmc_dev(host), "Initial signal voltage of 3.3v\n");
1176 	else if (!mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180))
1177 		dev_dbg(mmc_dev(host), "Initial signal voltage of 1.8v\n");
1178 	else if (!mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120))
1179 		dev_dbg(mmc_dev(host), "Initial signal voltage of 1.2v\n");
1180 }
1181 
1182 int mmc_host_set_uhs_voltage(struct mmc_host *host)
1183 {
1184 	u32 clock;
1185 
1186 	/*
1187 	 * During a signal voltage level switch, the clock must be gated
1188 	 * for 5 ms according to the SD spec
1189 	 */
1190 	clock = host->ios.clock;
1191 	host->ios.clock = 0;
1192 	mmc_set_ios(host);
1193 
1194 	if (mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180))
1195 		return -EAGAIN;
1196 
1197 	/* Keep clock gated for at least 10 ms, though spec only says 5 ms */
1198 	mmc_delay(10);
1199 	host->ios.clock = clock;
1200 	mmc_set_ios(host);
1201 
1202 	return 0;
1203 }
1204 
1205 int mmc_set_uhs_voltage(struct mmc_host *host, u32 ocr)
1206 {
1207 	struct mmc_command cmd = {};
1208 	int err = 0;
1209 
1210 	/*
1211 	 * If we cannot switch voltages, return failure so the caller
1212 	 * can continue without UHS mode
1213 	 */
1214 	if (!host->ops->start_signal_voltage_switch)
1215 		return -EPERM;
1216 	if (!host->ops->card_busy)
1217 		pr_warn("%s: cannot verify signal voltage switch\n",
1218 			mmc_hostname(host));
1219 
1220 	cmd.opcode = SD_SWITCH_VOLTAGE;
1221 	cmd.arg = 0;
1222 	cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
1223 
1224 	err = mmc_wait_for_cmd(host, &cmd, 0);
1225 	if (err)
1226 		return err;
1227 
1228 	if (!mmc_host_is_spi(host) && (cmd.resp[0] & R1_ERROR))
1229 		return -EIO;
1230 
1231 	/*
1232 	 * The card should drive cmd and dat[0:3] low immediately
1233 	 * after the response of cmd11, but wait 1 ms to be sure
1234 	 */
1235 	mmc_delay(1);
1236 	if (host->ops->card_busy && !host->ops->card_busy(host)) {
1237 		err = -EAGAIN;
1238 		goto power_cycle;
1239 	}
1240 
1241 	if (mmc_host_set_uhs_voltage(host)) {
1242 		/*
1243 		 * Voltages may not have been switched, but we've already
1244 		 * sent CMD11, so a power cycle is required anyway
1245 		 */
1246 		err = -EAGAIN;
1247 		goto power_cycle;
1248 	}
1249 
1250 	/* Wait for at least 1 ms according to spec */
1251 	mmc_delay(1);
1252 
1253 	/*
1254 	 * Failure to switch is indicated by the card holding
1255 	 * dat[0:3] low
1256 	 */
1257 	if (host->ops->card_busy && host->ops->card_busy(host))
1258 		err = -EAGAIN;
1259 
1260 power_cycle:
1261 	if (err) {
1262 		pr_debug("%s: Signal voltage switch failed, "
1263 			"power cycling card\n", mmc_hostname(host));
1264 		mmc_power_cycle(host, ocr);
1265 	}
1266 
1267 	return err;
1268 }
1269 
1270 /*
1271  * Select timing parameters for host.
1272  */
1273 void mmc_set_timing(struct mmc_host *host, unsigned int timing)
1274 {
1275 	host->ios.timing = timing;
1276 	mmc_set_ios(host);
1277 }
1278 
1279 /*
1280  * Select appropriate driver type for host.
1281  */
1282 void mmc_set_driver_type(struct mmc_host *host, unsigned int drv_type)
1283 {
1284 	host->ios.drv_type = drv_type;
1285 	mmc_set_ios(host);
1286 }
1287 
1288 int mmc_select_drive_strength(struct mmc_card *card, unsigned int max_dtr,
1289 			      int card_drv_type, int *drv_type)
1290 {
1291 	struct mmc_host *host = card->host;
1292 	int host_drv_type = SD_DRIVER_TYPE_B;
1293 
1294 	*drv_type = 0;
1295 
1296 	if (!host->ops->select_drive_strength)
1297 		return 0;
1298 
1299 	/* Use SD definition of driver strength for hosts */
1300 	if (host->caps & MMC_CAP_DRIVER_TYPE_A)
1301 		host_drv_type |= SD_DRIVER_TYPE_A;
1302 
1303 	if (host->caps & MMC_CAP_DRIVER_TYPE_C)
1304 		host_drv_type |= SD_DRIVER_TYPE_C;
1305 
1306 	if (host->caps & MMC_CAP_DRIVER_TYPE_D)
1307 		host_drv_type |= SD_DRIVER_TYPE_D;
1308 
1309 	/*
1310 	 * The drive strength that the hardware can support
1311 	 * depends on the board design.  Pass the appropriate
1312 	 * information and let the hardware specific code
1313 	 * return what is possible given the options
1314 	 */
1315 	return host->ops->select_drive_strength(card, max_dtr,
1316 						host_drv_type,
1317 						card_drv_type,
1318 						drv_type);
1319 }
1320 
1321 /*
1322  * Apply power to the MMC stack.  This is a two-stage process.
1323  * First, we enable power to the card without the clock running.
1324  * We then wait a bit for the power to stabilise.  Finally,
1325  * enable the bus drivers and clock to the card.
1326  *
1327  * We must _NOT_ enable the clock prior to power stablising.
1328  *
1329  * If a host does all the power sequencing itself, ignore the
1330  * initial MMC_POWER_UP stage.
1331  */
1332 void mmc_power_up(struct mmc_host *host, u32 ocr)
1333 {
1334 	if (host->ios.power_mode == MMC_POWER_ON)
1335 		return;
1336 
1337 	mmc_pwrseq_pre_power_on(host);
1338 
1339 	host->ios.vdd = fls(ocr) - 1;
1340 	host->ios.power_mode = MMC_POWER_UP;
1341 	/* Set initial state and call mmc_set_ios */
1342 	mmc_set_initial_state(host);
1343 
1344 	mmc_set_initial_signal_voltage(host);
1345 
1346 	/*
1347 	 * This delay should be sufficient to allow the power supply
1348 	 * to reach the minimum voltage.
1349 	 */
1350 	mmc_delay(host->ios.power_delay_ms);
1351 
1352 	mmc_pwrseq_post_power_on(host);
1353 
1354 	host->ios.clock = host->f_init;
1355 
1356 	host->ios.power_mode = MMC_POWER_ON;
1357 	mmc_set_ios(host);
1358 
1359 	/*
1360 	 * This delay must be at least 74 clock sizes, or 1 ms, or the
1361 	 * time required to reach a stable voltage.
1362 	 */
1363 	mmc_delay(host->ios.power_delay_ms);
1364 }
1365 
1366 void mmc_power_off(struct mmc_host *host)
1367 {
1368 	if (host->ios.power_mode == MMC_POWER_OFF)
1369 		return;
1370 
1371 	mmc_pwrseq_power_off(host);
1372 
1373 	host->ios.clock = 0;
1374 	host->ios.vdd = 0;
1375 
1376 	host->ios.power_mode = MMC_POWER_OFF;
1377 	/* Set initial state and call mmc_set_ios */
1378 	mmc_set_initial_state(host);
1379 
1380 	/*
1381 	 * Some configurations, such as the 802.11 SDIO card in the OLPC
1382 	 * XO-1.5, require a short delay after poweroff before the card
1383 	 * can be successfully turned on again.
1384 	 */
1385 	mmc_delay(1);
1386 }
1387 
1388 void mmc_power_cycle(struct mmc_host *host, u32 ocr)
1389 {
1390 	mmc_power_off(host);
1391 	/* Wait at least 1 ms according to SD spec */
1392 	mmc_delay(1);
1393 	mmc_power_up(host, ocr);
1394 }
1395 
1396 /*
1397  * Cleanup when the last reference to the bus operator is dropped.
1398  */
1399 static void __mmc_release_bus(struct mmc_host *host)
1400 {
1401 	WARN_ON(!host->bus_dead);
1402 
1403 	host->bus_ops = NULL;
1404 }
1405 
1406 /*
1407  * Increase reference count of bus operator
1408  */
1409 static inline void mmc_bus_get(struct mmc_host *host)
1410 {
1411 	unsigned long flags;
1412 
1413 	spin_lock_irqsave(&host->lock, flags);
1414 	host->bus_refs++;
1415 	spin_unlock_irqrestore(&host->lock, flags);
1416 }
1417 
1418 /*
1419  * Decrease reference count of bus operator and free it if
1420  * it is the last reference.
1421  */
1422 static inline void mmc_bus_put(struct mmc_host *host)
1423 {
1424 	unsigned long flags;
1425 
1426 	spin_lock_irqsave(&host->lock, flags);
1427 	host->bus_refs--;
1428 	if ((host->bus_refs == 0) && host->bus_ops)
1429 		__mmc_release_bus(host);
1430 	spin_unlock_irqrestore(&host->lock, flags);
1431 }
1432 
1433 /*
1434  * Assign a mmc bus handler to a host. Only one bus handler may control a
1435  * host at any given time.
1436  */
1437 void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops)
1438 {
1439 	unsigned long flags;
1440 
1441 	WARN_ON(!host->claimed);
1442 
1443 	spin_lock_irqsave(&host->lock, flags);
1444 
1445 	WARN_ON(host->bus_ops);
1446 	WARN_ON(host->bus_refs);
1447 
1448 	host->bus_ops = ops;
1449 	host->bus_refs = 1;
1450 	host->bus_dead = 0;
1451 
1452 	spin_unlock_irqrestore(&host->lock, flags);
1453 }
1454 
1455 /*
1456  * Remove the current bus handler from a host.
1457  */
1458 void mmc_detach_bus(struct mmc_host *host)
1459 {
1460 	unsigned long flags;
1461 
1462 	WARN_ON(!host->claimed);
1463 	WARN_ON(!host->bus_ops);
1464 
1465 	spin_lock_irqsave(&host->lock, flags);
1466 
1467 	host->bus_dead = 1;
1468 
1469 	spin_unlock_irqrestore(&host->lock, flags);
1470 
1471 	mmc_bus_put(host);
1472 }
1473 
1474 static void _mmc_detect_change(struct mmc_host *host, unsigned long delay,
1475 				bool cd_irq)
1476 {
1477 	/*
1478 	 * If the device is configured as wakeup, we prevent a new sleep for
1479 	 * 5 s to give provision for user space to consume the event.
1480 	 */
1481 	if (cd_irq && !(host->caps & MMC_CAP_NEEDS_POLL) &&
1482 		device_can_wakeup(mmc_dev(host)))
1483 		pm_wakeup_event(mmc_dev(host), 5000);
1484 
1485 	host->detect_change = 1;
1486 	mmc_schedule_delayed_work(&host->detect, delay);
1487 }
1488 
1489 /**
1490  *	mmc_detect_change - process change of state on a MMC socket
1491  *	@host: host which changed state.
1492  *	@delay: optional delay to wait before detection (jiffies)
1493  *
1494  *	MMC drivers should call this when they detect a card has been
1495  *	inserted or removed. The MMC layer will confirm that any
1496  *	present card is still functional, and initialize any newly
1497  *	inserted.
1498  */
1499 void mmc_detect_change(struct mmc_host *host, unsigned long delay)
1500 {
1501 	_mmc_detect_change(host, delay, true);
1502 }
1503 EXPORT_SYMBOL(mmc_detect_change);
1504 
1505 void mmc_init_erase(struct mmc_card *card)
1506 {
1507 	unsigned int sz;
1508 
1509 	if (is_power_of_2(card->erase_size))
1510 		card->erase_shift = ffs(card->erase_size) - 1;
1511 	else
1512 		card->erase_shift = 0;
1513 
1514 	/*
1515 	 * It is possible to erase an arbitrarily large area of an SD or MMC
1516 	 * card.  That is not desirable because it can take a long time
1517 	 * (minutes) potentially delaying more important I/O, and also the
1518 	 * timeout calculations become increasingly hugely over-estimated.
1519 	 * Consequently, 'pref_erase' is defined as a guide to limit erases
1520 	 * to that size and alignment.
1521 	 *
1522 	 * For SD cards that define Allocation Unit size, limit erases to one
1523 	 * Allocation Unit at a time.
1524 	 * For MMC, have a stab at ai good value and for modern cards it will
1525 	 * end up being 4MiB. Note that if the value is too small, it can end
1526 	 * up taking longer to erase. Also note, erase_size is already set to
1527 	 * High Capacity Erase Size if available when this function is called.
1528 	 */
1529 	if (mmc_card_sd(card) && card->ssr.au) {
1530 		card->pref_erase = card->ssr.au;
1531 		card->erase_shift = ffs(card->ssr.au) - 1;
1532 	} else if (card->erase_size) {
1533 		sz = (card->csd.capacity << (card->csd.read_blkbits - 9)) >> 11;
1534 		if (sz < 128)
1535 			card->pref_erase = 512 * 1024 / 512;
1536 		else if (sz < 512)
1537 			card->pref_erase = 1024 * 1024 / 512;
1538 		else if (sz < 1024)
1539 			card->pref_erase = 2 * 1024 * 1024 / 512;
1540 		else
1541 			card->pref_erase = 4 * 1024 * 1024 / 512;
1542 		if (card->pref_erase < card->erase_size)
1543 			card->pref_erase = card->erase_size;
1544 		else {
1545 			sz = card->pref_erase % card->erase_size;
1546 			if (sz)
1547 				card->pref_erase += card->erase_size - sz;
1548 		}
1549 	} else
1550 		card->pref_erase = 0;
1551 }
1552 
1553 static unsigned int mmc_mmc_erase_timeout(struct mmc_card *card,
1554 				          unsigned int arg, unsigned int qty)
1555 {
1556 	unsigned int erase_timeout;
1557 
1558 	if (arg == MMC_DISCARD_ARG ||
1559 	    (arg == MMC_TRIM_ARG && card->ext_csd.rev >= 6)) {
1560 		erase_timeout = card->ext_csd.trim_timeout;
1561 	} else if (card->ext_csd.erase_group_def & 1) {
1562 		/* High Capacity Erase Group Size uses HC timeouts */
1563 		if (arg == MMC_TRIM_ARG)
1564 			erase_timeout = card->ext_csd.trim_timeout;
1565 		else
1566 			erase_timeout = card->ext_csd.hc_erase_timeout;
1567 	} else {
1568 		/* CSD Erase Group Size uses write timeout */
1569 		unsigned int mult = (10 << card->csd.r2w_factor);
1570 		unsigned int timeout_clks = card->csd.taac_clks * mult;
1571 		unsigned int timeout_us;
1572 
1573 		/* Avoid overflow: e.g. taac_ns=80000000 mult=1280 */
1574 		if (card->csd.taac_ns < 1000000)
1575 			timeout_us = (card->csd.taac_ns * mult) / 1000;
1576 		else
1577 			timeout_us = (card->csd.taac_ns / 1000) * mult;
1578 
1579 		/*
1580 		 * ios.clock is only a target.  The real clock rate might be
1581 		 * less but not that much less, so fudge it by multiplying by 2.
1582 		 */
1583 		timeout_clks <<= 1;
1584 		timeout_us += (timeout_clks * 1000) /
1585 			      (card->host->ios.clock / 1000);
1586 
1587 		erase_timeout = timeout_us / 1000;
1588 
1589 		/*
1590 		 * Theoretically, the calculation could underflow so round up
1591 		 * to 1ms in that case.
1592 		 */
1593 		if (!erase_timeout)
1594 			erase_timeout = 1;
1595 	}
1596 
1597 	/* Multiplier for secure operations */
1598 	if (arg & MMC_SECURE_ARGS) {
1599 		if (arg == MMC_SECURE_ERASE_ARG)
1600 			erase_timeout *= card->ext_csd.sec_erase_mult;
1601 		else
1602 			erase_timeout *= card->ext_csd.sec_trim_mult;
1603 	}
1604 
1605 	erase_timeout *= qty;
1606 
1607 	/*
1608 	 * Ensure at least a 1 second timeout for SPI as per
1609 	 * 'mmc_set_data_timeout()'
1610 	 */
1611 	if (mmc_host_is_spi(card->host) && erase_timeout < 1000)
1612 		erase_timeout = 1000;
1613 
1614 	return erase_timeout;
1615 }
1616 
1617 static unsigned int mmc_sd_erase_timeout(struct mmc_card *card,
1618 					 unsigned int arg,
1619 					 unsigned int qty)
1620 {
1621 	unsigned int erase_timeout;
1622 
1623 	/* for DISCARD none of the below calculation applies.
1624 	 * the busy timeout is 250msec per discard command.
1625 	 */
1626 	if (arg == SD_DISCARD_ARG)
1627 		return SD_DISCARD_TIMEOUT_MS;
1628 
1629 	if (card->ssr.erase_timeout) {
1630 		/* Erase timeout specified in SD Status Register (SSR) */
1631 		erase_timeout = card->ssr.erase_timeout * qty +
1632 				card->ssr.erase_offset;
1633 	} else {
1634 		/*
1635 		 * Erase timeout not specified in SD Status Register (SSR) so
1636 		 * use 250ms per write block.
1637 		 */
1638 		erase_timeout = 250 * qty;
1639 	}
1640 
1641 	/* Must not be less than 1 second */
1642 	if (erase_timeout < 1000)
1643 		erase_timeout = 1000;
1644 
1645 	return erase_timeout;
1646 }
1647 
1648 static unsigned int mmc_erase_timeout(struct mmc_card *card,
1649 				      unsigned int arg,
1650 				      unsigned int qty)
1651 {
1652 	if (mmc_card_sd(card))
1653 		return mmc_sd_erase_timeout(card, arg, qty);
1654 	else
1655 		return mmc_mmc_erase_timeout(card, arg, qty);
1656 }
1657 
1658 static int mmc_do_erase(struct mmc_card *card, unsigned int from,
1659 			unsigned int to, unsigned int arg)
1660 {
1661 	struct mmc_command cmd = {};
1662 	unsigned int qty = 0, busy_timeout = 0;
1663 	bool use_r1b_resp = false;
1664 	unsigned long timeout;
1665 	int loop_udelay=64, udelay_max=32768;
1666 	int err;
1667 
1668 	mmc_retune_hold(card->host);
1669 
1670 	/*
1671 	 * qty is used to calculate the erase timeout which depends on how many
1672 	 * erase groups (or allocation units in SD terminology) are affected.
1673 	 * We count erasing part of an erase group as one erase group.
1674 	 * For SD, the allocation units are always a power of 2.  For MMC, the
1675 	 * erase group size is almost certainly also power of 2, but it does not
1676 	 * seem to insist on that in the JEDEC standard, so we fall back to
1677 	 * division in that case.  SD may not specify an allocation unit size,
1678 	 * in which case the timeout is based on the number of write blocks.
1679 	 *
1680 	 * Note that the timeout for secure trim 2 will only be correct if the
1681 	 * number of erase groups specified is the same as the total of all
1682 	 * preceding secure trim 1 commands.  Since the power may have been
1683 	 * lost since the secure trim 1 commands occurred, it is generally
1684 	 * impossible to calculate the secure trim 2 timeout correctly.
1685 	 */
1686 	if (card->erase_shift)
1687 		qty += ((to >> card->erase_shift) -
1688 			(from >> card->erase_shift)) + 1;
1689 	else if (mmc_card_sd(card))
1690 		qty += to - from + 1;
1691 	else
1692 		qty += ((to / card->erase_size) -
1693 			(from / card->erase_size)) + 1;
1694 
1695 	if (!mmc_card_blockaddr(card)) {
1696 		from <<= 9;
1697 		to <<= 9;
1698 	}
1699 
1700 	if (mmc_card_sd(card))
1701 		cmd.opcode = SD_ERASE_WR_BLK_START;
1702 	else
1703 		cmd.opcode = MMC_ERASE_GROUP_START;
1704 	cmd.arg = from;
1705 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
1706 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
1707 	if (err) {
1708 		pr_err("mmc_erase: group start error %d, "
1709 		       "status %#x\n", err, cmd.resp[0]);
1710 		err = -EIO;
1711 		goto out;
1712 	}
1713 
1714 	memset(&cmd, 0, sizeof(struct mmc_command));
1715 	if (mmc_card_sd(card))
1716 		cmd.opcode = SD_ERASE_WR_BLK_END;
1717 	else
1718 		cmd.opcode = MMC_ERASE_GROUP_END;
1719 	cmd.arg = to;
1720 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
1721 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
1722 	if (err) {
1723 		pr_err("mmc_erase: group end error %d, status %#x\n",
1724 		       err, cmd.resp[0]);
1725 		err = -EIO;
1726 		goto out;
1727 	}
1728 
1729 	memset(&cmd, 0, sizeof(struct mmc_command));
1730 	cmd.opcode = MMC_ERASE;
1731 	cmd.arg = arg;
1732 	busy_timeout = mmc_erase_timeout(card, arg, qty);
1733 	/*
1734 	 * If the host controller supports busy signalling and the timeout for
1735 	 * the erase operation does not exceed the max_busy_timeout, we should
1736 	 * use R1B response. Or we need to prevent the host from doing hw busy
1737 	 * detection, which is done by converting to a R1 response instead.
1738 	 */
1739 	if (card->host->max_busy_timeout &&
1740 	    busy_timeout > card->host->max_busy_timeout) {
1741 		cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
1742 	} else {
1743 		cmd.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
1744 		cmd.busy_timeout = busy_timeout;
1745 		use_r1b_resp = true;
1746 	}
1747 
1748 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
1749 	if (err) {
1750 		pr_err("mmc_erase: erase error %d, status %#x\n",
1751 		       err, cmd.resp[0]);
1752 		err = -EIO;
1753 		goto out;
1754 	}
1755 
1756 	if (mmc_host_is_spi(card->host))
1757 		goto out;
1758 
1759 	/*
1760 	 * In case of when R1B + MMC_CAP_WAIT_WHILE_BUSY is used, the polling
1761 	 * shall be avoided.
1762 	 */
1763 	if ((card->host->caps & MMC_CAP_WAIT_WHILE_BUSY) && use_r1b_resp)
1764 		goto out;
1765 
1766 	timeout = jiffies + msecs_to_jiffies(busy_timeout);
1767 	do {
1768 		memset(&cmd, 0, sizeof(struct mmc_command));
1769 		cmd.opcode = MMC_SEND_STATUS;
1770 		cmd.arg = card->rca << 16;
1771 		cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
1772 		/* Do not retry else we can't see errors */
1773 		err = mmc_wait_for_cmd(card->host, &cmd, 0);
1774 		if (err || R1_STATUS(cmd.resp[0])) {
1775 			pr_err("error %d requesting status %#x\n",
1776 				err, cmd.resp[0]);
1777 			err = -EIO;
1778 			goto out;
1779 		}
1780 
1781 		/* Timeout if the device never becomes ready for data and
1782 		 * never leaves the program state.
1783 		 */
1784 		if (time_after(jiffies, timeout)) {
1785 			pr_err("%s: Card stuck in programming state! %s\n",
1786 				mmc_hostname(card->host), __func__);
1787 			err =  -EIO;
1788 			goto out;
1789 		}
1790 		if ((cmd.resp[0] & R1_READY_FOR_DATA) &&
1791 		    R1_CURRENT_STATE(cmd.resp[0]) != R1_STATE_PRG)
1792 			break;
1793 
1794 		usleep_range(loop_udelay, loop_udelay*2);
1795 		if (loop_udelay < udelay_max)
1796 			loop_udelay *= 2;
1797 	} while (1);
1798 
1799 out:
1800 	mmc_retune_release(card->host);
1801 	return err;
1802 }
1803 
1804 static unsigned int mmc_align_erase_size(struct mmc_card *card,
1805 					 unsigned int *from,
1806 					 unsigned int *to,
1807 					 unsigned int nr)
1808 {
1809 	unsigned int from_new = *from, nr_new = nr, rem;
1810 
1811 	/*
1812 	 * When the 'card->erase_size' is power of 2, we can use round_up/down()
1813 	 * to align the erase size efficiently.
1814 	 */
1815 	if (is_power_of_2(card->erase_size)) {
1816 		unsigned int temp = from_new;
1817 
1818 		from_new = round_up(temp, card->erase_size);
1819 		rem = from_new - temp;
1820 
1821 		if (nr_new > rem)
1822 			nr_new -= rem;
1823 		else
1824 			return 0;
1825 
1826 		nr_new = round_down(nr_new, card->erase_size);
1827 	} else {
1828 		rem = from_new % card->erase_size;
1829 		if (rem) {
1830 			rem = card->erase_size - rem;
1831 			from_new += rem;
1832 			if (nr_new > rem)
1833 				nr_new -= rem;
1834 			else
1835 				return 0;
1836 		}
1837 
1838 		rem = nr_new % card->erase_size;
1839 		if (rem)
1840 			nr_new -= rem;
1841 	}
1842 
1843 	if (nr_new == 0)
1844 		return 0;
1845 
1846 	*to = from_new + nr_new;
1847 	*from = from_new;
1848 
1849 	return nr_new;
1850 }
1851 
1852 /**
1853  * mmc_erase - erase sectors.
1854  * @card: card to erase
1855  * @from: first sector to erase
1856  * @nr: number of sectors to erase
1857  * @arg: erase command argument
1858  *
1859  * Caller must claim host before calling this function.
1860  */
1861 int mmc_erase(struct mmc_card *card, unsigned int from, unsigned int nr,
1862 	      unsigned int arg)
1863 {
1864 	unsigned int rem, to = from + nr;
1865 	int err;
1866 
1867 	if (!(card->host->caps & MMC_CAP_ERASE) ||
1868 	    !(card->csd.cmdclass & CCC_ERASE))
1869 		return -EOPNOTSUPP;
1870 
1871 	if (!card->erase_size)
1872 		return -EOPNOTSUPP;
1873 
1874 	if (mmc_card_sd(card) && arg != SD_ERASE_ARG && arg != SD_DISCARD_ARG)
1875 		return -EOPNOTSUPP;
1876 
1877 	if (mmc_card_mmc(card) && (arg & MMC_SECURE_ARGS) &&
1878 	    !(card->ext_csd.sec_feature_support & EXT_CSD_SEC_ER_EN))
1879 		return -EOPNOTSUPP;
1880 
1881 	if (mmc_card_mmc(card) && (arg & MMC_TRIM_ARGS) &&
1882 	    !(card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN))
1883 		return -EOPNOTSUPP;
1884 
1885 	if (arg == MMC_SECURE_ERASE_ARG) {
1886 		if (from % card->erase_size || nr % card->erase_size)
1887 			return -EINVAL;
1888 	}
1889 
1890 	if (arg == MMC_ERASE_ARG)
1891 		nr = mmc_align_erase_size(card, &from, &to, nr);
1892 
1893 	if (nr == 0)
1894 		return 0;
1895 
1896 	if (to <= from)
1897 		return -EINVAL;
1898 
1899 	/* 'from' and 'to' are inclusive */
1900 	to -= 1;
1901 
1902 	/*
1903 	 * Special case where only one erase-group fits in the timeout budget:
1904 	 * If the region crosses an erase-group boundary on this particular
1905 	 * case, we will be trimming more than one erase-group which, does not
1906 	 * fit in the timeout budget of the controller, so we need to split it
1907 	 * and call mmc_do_erase() twice if necessary. This special case is
1908 	 * identified by the card->eg_boundary flag.
1909 	 */
1910 	rem = card->erase_size - (from % card->erase_size);
1911 	if ((arg & MMC_TRIM_ARGS) && (card->eg_boundary) && (nr > rem)) {
1912 		err = mmc_do_erase(card, from, from + rem - 1, arg);
1913 		from += rem;
1914 		if ((err) || (to <= from))
1915 			return err;
1916 	}
1917 
1918 	return mmc_do_erase(card, from, to, arg);
1919 }
1920 EXPORT_SYMBOL(mmc_erase);
1921 
1922 int mmc_can_erase(struct mmc_card *card)
1923 {
1924 	if ((card->host->caps & MMC_CAP_ERASE) &&
1925 	    (card->csd.cmdclass & CCC_ERASE) && card->erase_size)
1926 		return 1;
1927 	return 0;
1928 }
1929 EXPORT_SYMBOL(mmc_can_erase);
1930 
1931 int mmc_can_trim(struct mmc_card *card)
1932 {
1933 	if ((card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN) &&
1934 	    (!(card->quirks & MMC_QUIRK_TRIM_BROKEN)))
1935 		return 1;
1936 	return 0;
1937 }
1938 EXPORT_SYMBOL(mmc_can_trim);
1939 
1940 int mmc_can_discard(struct mmc_card *card)
1941 {
1942 	/*
1943 	 * As there's no way to detect the discard support bit at v4.5
1944 	 * use the s/w feature support filed.
1945 	 */
1946 	if (card->ext_csd.feature_support & MMC_DISCARD_FEATURE)
1947 		return 1;
1948 	return 0;
1949 }
1950 EXPORT_SYMBOL(mmc_can_discard);
1951 
1952 int mmc_can_sanitize(struct mmc_card *card)
1953 {
1954 	if (!mmc_can_trim(card) && !mmc_can_erase(card))
1955 		return 0;
1956 	if (card->ext_csd.sec_feature_support & EXT_CSD_SEC_SANITIZE)
1957 		return 1;
1958 	return 0;
1959 }
1960 EXPORT_SYMBOL(mmc_can_sanitize);
1961 
1962 int mmc_can_secure_erase_trim(struct mmc_card *card)
1963 {
1964 	if ((card->ext_csd.sec_feature_support & EXT_CSD_SEC_ER_EN) &&
1965 	    !(card->quirks & MMC_QUIRK_SEC_ERASE_TRIM_BROKEN))
1966 		return 1;
1967 	return 0;
1968 }
1969 EXPORT_SYMBOL(mmc_can_secure_erase_trim);
1970 
1971 int mmc_erase_group_aligned(struct mmc_card *card, unsigned int from,
1972 			    unsigned int nr)
1973 {
1974 	if (!card->erase_size)
1975 		return 0;
1976 	if (from % card->erase_size || nr % card->erase_size)
1977 		return 0;
1978 	return 1;
1979 }
1980 EXPORT_SYMBOL(mmc_erase_group_aligned);
1981 
1982 static unsigned int mmc_do_calc_max_discard(struct mmc_card *card,
1983 					    unsigned int arg)
1984 {
1985 	struct mmc_host *host = card->host;
1986 	unsigned int max_discard, x, y, qty = 0, max_qty, min_qty, timeout;
1987 	unsigned int last_timeout = 0;
1988 	unsigned int max_busy_timeout = host->max_busy_timeout ?
1989 			host->max_busy_timeout : MMC_ERASE_TIMEOUT_MS;
1990 
1991 	if (card->erase_shift) {
1992 		max_qty = UINT_MAX >> card->erase_shift;
1993 		min_qty = card->pref_erase >> card->erase_shift;
1994 	} else if (mmc_card_sd(card)) {
1995 		max_qty = UINT_MAX;
1996 		min_qty = card->pref_erase;
1997 	} else {
1998 		max_qty = UINT_MAX / card->erase_size;
1999 		min_qty = card->pref_erase / card->erase_size;
2000 	}
2001 
2002 	/*
2003 	 * We should not only use 'host->max_busy_timeout' as the limitation
2004 	 * when deciding the max discard sectors. We should set a balance value
2005 	 * to improve the erase speed, and it can not get too long timeout at
2006 	 * the same time.
2007 	 *
2008 	 * Here we set 'card->pref_erase' as the minimal discard sectors no
2009 	 * matter what size of 'host->max_busy_timeout', but if the
2010 	 * 'host->max_busy_timeout' is large enough for more discard sectors,
2011 	 * then we can continue to increase the max discard sectors until we
2012 	 * get a balance value. In cases when the 'host->max_busy_timeout'
2013 	 * isn't specified, use the default max erase timeout.
2014 	 */
2015 	do {
2016 		y = 0;
2017 		for (x = 1; x && x <= max_qty && max_qty - x >= qty; x <<= 1) {
2018 			timeout = mmc_erase_timeout(card, arg, qty + x);
2019 
2020 			if (qty + x > min_qty && timeout > max_busy_timeout)
2021 				break;
2022 
2023 			if (timeout < last_timeout)
2024 				break;
2025 			last_timeout = timeout;
2026 			y = x;
2027 		}
2028 		qty += y;
2029 	} while (y);
2030 
2031 	if (!qty)
2032 		return 0;
2033 
2034 	/*
2035 	 * When specifying a sector range to trim, chances are we might cross
2036 	 * an erase-group boundary even if the amount of sectors is less than
2037 	 * one erase-group.
2038 	 * If we can only fit one erase-group in the controller timeout budget,
2039 	 * we have to care that erase-group boundaries are not crossed by a
2040 	 * single trim operation. We flag that special case with "eg_boundary".
2041 	 * In all other cases we can just decrement qty and pretend that we
2042 	 * always touch (qty + 1) erase-groups as a simple optimization.
2043 	 */
2044 	if (qty == 1)
2045 		card->eg_boundary = 1;
2046 	else
2047 		qty--;
2048 
2049 	/* Convert qty to sectors */
2050 	if (card->erase_shift)
2051 		max_discard = qty << card->erase_shift;
2052 	else if (mmc_card_sd(card))
2053 		max_discard = qty + 1;
2054 	else
2055 		max_discard = qty * card->erase_size;
2056 
2057 	return max_discard;
2058 }
2059 
2060 unsigned int mmc_calc_max_discard(struct mmc_card *card)
2061 {
2062 	struct mmc_host *host = card->host;
2063 	unsigned int max_discard, max_trim;
2064 
2065 	/*
2066 	 * Without erase_group_def set, MMC erase timeout depends on clock
2067 	 * frequence which can change.  In that case, the best choice is
2068 	 * just the preferred erase size.
2069 	 */
2070 	if (mmc_card_mmc(card) && !(card->ext_csd.erase_group_def & 1))
2071 		return card->pref_erase;
2072 
2073 	max_discard = mmc_do_calc_max_discard(card, MMC_ERASE_ARG);
2074 	if (mmc_can_trim(card)) {
2075 		max_trim = mmc_do_calc_max_discard(card, MMC_TRIM_ARG);
2076 		if (max_trim < max_discard || max_discard == 0)
2077 			max_discard = max_trim;
2078 	} else if (max_discard < card->erase_size) {
2079 		max_discard = 0;
2080 	}
2081 	pr_debug("%s: calculated max. discard sectors %u for timeout %u ms\n",
2082 		mmc_hostname(host), max_discard, host->max_busy_timeout ?
2083 		host->max_busy_timeout : MMC_ERASE_TIMEOUT_MS);
2084 	return max_discard;
2085 }
2086 EXPORT_SYMBOL(mmc_calc_max_discard);
2087 
2088 bool mmc_card_is_blockaddr(struct mmc_card *card)
2089 {
2090 	return card ? mmc_card_blockaddr(card) : false;
2091 }
2092 EXPORT_SYMBOL(mmc_card_is_blockaddr);
2093 
2094 int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen)
2095 {
2096 	struct mmc_command cmd = {};
2097 
2098 	if (mmc_card_blockaddr(card) || mmc_card_ddr52(card) ||
2099 	    mmc_card_hs400(card) || mmc_card_hs400es(card))
2100 		return 0;
2101 
2102 	cmd.opcode = MMC_SET_BLOCKLEN;
2103 	cmd.arg = blocklen;
2104 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
2105 	return mmc_wait_for_cmd(card->host, &cmd, 5);
2106 }
2107 EXPORT_SYMBOL(mmc_set_blocklen);
2108 
2109 static void mmc_hw_reset_for_init(struct mmc_host *host)
2110 {
2111 	mmc_pwrseq_reset(host);
2112 
2113 	if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
2114 		return;
2115 	host->ops->hw_reset(host);
2116 }
2117 
2118 int mmc_hw_reset(struct mmc_host *host)
2119 {
2120 	int ret;
2121 
2122 	if (!host->card)
2123 		return -EINVAL;
2124 
2125 	mmc_bus_get(host);
2126 	if (!host->bus_ops || host->bus_dead || !host->bus_ops->hw_reset) {
2127 		mmc_bus_put(host);
2128 		return -EOPNOTSUPP;
2129 	}
2130 
2131 	ret = host->bus_ops->hw_reset(host);
2132 	mmc_bus_put(host);
2133 
2134 	if (ret)
2135 		pr_warn("%s: tried to HW reset card, got error %d\n",
2136 			mmc_hostname(host), ret);
2137 
2138 	return ret;
2139 }
2140 EXPORT_SYMBOL(mmc_hw_reset);
2141 
2142 int mmc_sw_reset(struct mmc_host *host)
2143 {
2144 	int ret;
2145 
2146 	if (!host->card)
2147 		return -EINVAL;
2148 
2149 	mmc_bus_get(host);
2150 	if (!host->bus_ops || host->bus_dead || !host->bus_ops->sw_reset) {
2151 		mmc_bus_put(host);
2152 		return -EOPNOTSUPP;
2153 	}
2154 
2155 	ret = host->bus_ops->sw_reset(host);
2156 	mmc_bus_put(host);
2157 
2158 	if (ret)
2159 		pr_warn("%s: tried to SW reset card, got error %d\n",
2160 			mmc_hostname(host), ret);
2161 
2162 	return ret;
2163 }
2164 EXPORT_SYMBOL(mmc_sw_reset);
2165 
2166 static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
2167 {
2168 	host->f_init = freq;
2169 
2170 	pr_debug("%s: %s: trying to init card at %u Hz\n",
2171 		mmc_hostname(host), __func__, host->f_init);
2172 
2173 	mmc_power_up(host, host->ocr_avail);
2174 
2175 	/*
2176 	 * Some eMMCs (with VCCQ always on) may not be reset after power up, so
2177 	 * do a hardware reset if possible.
2178 	 */
2179 	mmc_hw_reset_for_init(host);
2180 
2181 	/*
2182 	 * sdio_reset sends CMD52 to reset card.  Since we do not know
2183 	 * if the card is being re-initialized, just send it.  CMD52
2184 	 * should be ignored by SD/eMMC cards.
2185 	 * Skip it if we already know that we do not support SDIO commands
2186 	 */
2187 	if (!(host->caps2 & MMC_CAP2_NO_SDIO))
2188 		sdio_reset(host);
2189 
2190 	mmc_go_idle(host);
2191 
2192 	if (!(host->caps2 & MMC_CAP2_NO_SD))
2193 		mmc_send_if_cond(host, host->ocr_avail);
2194 
2195 	/* Order's important: probe SDIO, then SD, then MMC */
2196 	if (!(host->caps2 & MMC_CAP2_NO_SDIO))
2197 		if (!mmc_attach_sdio(host))
2198 			return 0;
2199 
2200 	if (!(host->caps2 & MMC_CAP2_NO_SD))
2201 		if (!mmc_attach_sd(host))
2202 			return 0;
2203 
2204 	if (!(host->caps2 & MMC_CAP2_NO_MMC))
2205 		if (!mmc_attach_mmc(host))
2206 			return 0;
2207 
2208 	mmc_power_off(host);
2209 	return -EIO;
2210 }
2211 
2212 int _mmc_detect_card_removed(struct mmc_host *host)
2213 {
2214 	int ret;
2215 
2216 	if (!host->card || mmc_card_removed(host->card))
2217 		return 1;
2218 
2219 	ret = host->bus_ops->alive(host);
2220 
2221 	/*
2222 	 * Card detect status and alive check may be out of sync if card is
2223 	 * removed slowly, when card detect switch changes while card/slot
2224 	 * pads are still contacted in hardware (refer to "SD Card Mechanical
2225 	 * Addendum, Appendix C: Card Detection Switch"). So reschedule a
2226 	 * detect work 200ms later for this case.
2227 	 */
2228 	if (!ret && host->ops->get_cd && !host->ops->get_cd(host)) {
2229 		mmc_detect_change(host, msecs_to_jiffies(200));
2230 		pr_debug("%s: card removed too slowly\n", mmc_hostname(host));
2231 	}
2232 
2233 	if (ret) {
2234 		mmc_card_set_removed(host->card);
2235 		pr_debug("%s: card remove detected\n", mmc_hostname(host));
2236 	}
2237 
2238 	return ret;
2239 }
2240 
2241 int mmc_detect_card_removed(struct mmc_host *host)
2242 {
2243 	struct mmc_card *card = host->card;
2244 	int ret;
2245 
2246 	WARN_ON(!host->claimed);
2247 
2248 	if (!card)
2249 		return 1;
2250 
2251 	if (!mmc_card_is_removable(host))
2252 		return 0;
2253 
2254 	ret = mmc_card_removed(card);
2255 	/*
2256 	 * The card will be considered unchanged unless we have been asked to
2257 	 * detect a change or host requires polling to provide card detection.
2258 	 */
2259 	if (!host->detect_change && !(host->caps & MMC_CAP_NEEDS_POLL))
2260 		return ret;
2261 
2262 	host->detect_change = 0;
2263 	if (!ret) {
2264 		ret = _mmc_detect_card_removed(host);
2265 		if (ret && (host->caps & MMC_CAP_NEEDS_POLL)) {
2266 			/*
2267 			 * Schedule a detect work as soon as possible to let a
2268 			 * rescan handle the card removal.
2269 			 */
2270 			cancel_delayed_work(&host->detect);
2271 			_mmc_detect_change(host, 0, false);
2272 		}
2273 	}
2274 
2275 	return ret;
2276 }
2277 EXPORT_SYMBOL(mmc_detect_card_removed);
2278 
2279 void mmc_rescan(struct work_struct *work)
2280 {
2281 	struct mmc_host *host =
2282 		container_of(work, struct mmc_host, detect.work);
2283 	int i;
2284 
2285 	if (host->rescan_disable)
2286 		return;
2287 
2288 	/* If there is a non-removable card registered, only scan once */
2289 	if (!mmc_card_is_removable(host) && host->rescan_entered)
2290 		return;
2291 	host->rescan_entered = 1;
2292 
2293 	if (host->trigger_card_event && host->ops->card_event) {
2294 		mmc_claim_host(host);
2295 		host->ops->card_event(host);
2296 		mmc_release_host(host);
2297 		host->trigger_card_event = false;
2298 	}
2299 
2300 	mmc_bus_get(host);
2301 
2302 	/*
2303 	 * if there is a _removable_ card registered, check whether it is
2304 	 * still present
2305 	 */
2306 	if (host->bus_ops && !host->bus_dead && mmc_card_is_removable(host))
2307 		host->bus_ops->detect(host);
2308 
2309 	host->detect_change = 0;
2310 
2311 	/*
2312 	 * Let mmc_bus_put() free the bus/bus_ops if we've found that
2313 	 * the card is no longer present.
2314 	 */
2315 	mmc_bus_put(host);
2316 	mmc_bus_get(host);
2317 
2318 	/* if there still is a card present, stop here */
2319 	if (host->bus_ops != NULL) {
2320 		mmc_bus_put(host);
2321 		goto out;
2322 	}
2323 
2324 	/*
2325 	 * Only we can add a new handler, so it's safe to
2326 	 * release the lock here.
2327 	 */
2328 	mmc_bus_put(host);
2329 
2330 	mmc_claim_host(host);
2331 	if (mmc_card_is_removable(host) && host->ops->get_cd &&
2332 			host->ops->get_cd(host) == 0) {
2333 		mmc_power_off(host);
2334 		mmc_release_host(host);
2335 		goto out;
2336 	}
2337 
2338 	for (i = 0; i < ARRAY_SIZE(freqs); i++) {
2339 		if (!mmc_rescan_try_freq(host, max(freqs[i], host->f_min)))
2340 			break;
2341 		if (freqs[i] <= host->f_min)
2342 			break;
2343 	}
2344 	mmc_release_host(host);
2345 
2346  out:
2347 	if (host->caps & MMC_CAP_NEEDS_POLL)
2348 		mmc_schedule_delayed_work(&host->detect, HZ);
2349 }
2350 
2351 void mmc_start_host(struct mmc_host *host)
2352 {
2353 	host->f_init = max(freqs[0], host->f_min);
2354 	host->rescan_disable = 0;
2355 	host->ios.power_mode = MMC_POWER_UNDEFINED;
2356 
2357 	if (!(host->caps2 & MMC_CAP2_NO_PRESCAN_POWERUP)) {
2358 		mmc_claim_host(host);
2359 		mmc_power_up(host, host->ocr_avail);
2360 		mmc_release_host(host);
2361 	}
2362 
2363 	mmc_gpiod_request_cd_irq(host);
2364 	_mmc_detect_change(host, 0, false);
2365 }
2366 
2367 void mmc_stop_host(struct mmc_host *host)
2368 {
2369 	if (host->slot.cd_irq >= 0) {
2370 		mmc_gpio_set_cd_wake(host, false);
2371 		disable_irq(host->slot.cd_irq);
2372 	}
2373 
2374 	host->rescan_disable = 1;
2375 	cancel_delayed_work_sync(&host->detect);
2376 
2377 	/* clear pm flags now and let card drivers set them as needed */
2378 	host->pm_flags = 0;
2379 
2380 	mmc_bus_get(host);
2381 	if (host->bus_ops && !host->bus_dead) {
2382 		/* Calling bus_ops->remove() with a claimed host can deadlock */
2383 		host->bus_ops->remove(host);
2384 		mmc_claim_host(host);
2385 		mmc_detach_bus(host);
2386 		mmc_power_off(host);
2387 		mmc_release_host(host);
2388 		mmc_bus_put(host);
2389 		return;
2390 	}
2391 	mmc_bus_put(host);
2392 
2393 	mmc_claim_host(host);
2394 	mmc_power_off(host);
2395 	mmc_release_host(host);
2396 }
2397 
2398 #ifdef CONFIG_PM_SLEEP
2399 /* Do the card removal on suspend if card is assumed removeable
2400  * Do that in pm notifier while userspace isn't yet frozen, so we will be able
2401    to sync the card.
2402 */
2403 static int mmc_pm_notify(struct notifier_block *notify_block,
2404 			unsigned long mode, void *unused)
2405 {
2406 	struct mmc_host *host = container_of(
2407 		notify_block, struct mmc_host, pm_notify);
2408 	unsigned long flags;
2409 	int err = 0;
2410 
2411 	switch (mode) {
2412 	case PM_HIBERNATION_PREPARE:
2413 	case PM_SUSPEND_PREPARE:
2414 	case PM_RESTORE_PREPARE:
2415 		spin_lock_irqsave(&host->lock, flags);
2416 		host->rescan_disable = 1;
2417 		spin_unlock_irqrestore(&host->lock, flags);
2418 		cancel_delayed_work_sync(&host->detect);
2419 
2420 		if (!host->bus_ops)
2421 			break;
2422 
2423 		/* Validate prerequisites for suspend */
2424 		if (host->bus_ops->pre_suspend)
2425 			err = host->bus_ops->pre_suspend(host);
2426 		if (!err)
2427 			break;
2428 
2429 		if (!mmc_card_is_removable(host)) {
2430 			dev_warn(mmc_dev(host),
2431 				 "pre_suspend failed for non-removable host: "
2432 				 "%d\n", err);
2433 			/* Avoid removing non-removable hosts */
2434 			break;
2435 		}
2436 
2437 		/* Calling bus_ops->remove() with a claimed host can deadlock */
2438 		host->bus_ops->remove(host);
2439 		mmc_claim_host(host);
2440 		mmc_detach_bus(host);
2441 		mmc_power_off(host);
2442 		mmc_release_host(host);
2443 		host->pm_flags = 0;
2444 		break;
2445 
2446 	case PM_POST_SUSPEND:
2447 	case PM_POST_HIBERNATION:
2448 	case PM_POST_RESTORE:
2449 
2450 		spin_lock_irqsave(&host->lock, flags);
2451 		host->rescan_disable = 0;
2452 		spin_unlock_irqrestore(&host->lock, flags);
2453 		_mmc_detect_change(host, 0, false);
2454 
2455 	}
2456 
2457 	return 0;
2458 }
2459 
2460 void mmc_register_pm_notifier(struct mmc_host *host)
2461 {
2462 	host->pm_notify.notifier_call = mmc_pm_notify;
2463 	register_pm_notifier(&host->pm_notify);
2464 }
2465 
2466 void mmc_unregister_pm_notifier(struct mmc_host *host)
2467 {
2468 	unregister_pm_notifier(&host->pm_notify);
2469 }
2470 #endif
2471 
2472 static int __init mmc_init(void)
2473 {
2474 	int ret;
2475 
2476 	ret = mmc_register_bus();
2477 	if (ret)
2478 		return ret;
2479 
2480 	ret = mmc_register_host_class();
2481 	if (ret)
2482 		goto unregister_bus;
2483 
2484 	ret = sdio_register_bus();
2485 	if (ret)
2486 		goto unregister_host_class;
2487 
2488 	return 0;
2489 
2490 unregister_host_class:
2491 	mmc_unregister_host_class();
2492 unregister_bus:
2493 	mmc_unregister_bus();
2494 	return ret;
2495 }
2496 
2497 static void __exit mmc_exit(void)
2498 {
2499 	sdio_unregister_bus();
2500 	mmc_unregister_host_class();
2501 	mmc_unregister_bus();
2502 }
2503 
2504 subsys_initcall(mmc_init);
2505 module_exit(mmc_exit);
2506 
2507 MODULE_LICENSE("GPL");
2508