• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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/regulator/consumer.h>
25 #include <linux/pm_runtime.h>
26 #include <linux/pm_wakeup.h>
27 #include <linux/suspend.h>
28 #include <linux/fault-inject.h>
29 #include <linux/random.h>
30 #include <linux/slab.h>
31 #include <linux/of.h>
32 
33 #include <linux/mmc/card.h>
34 #include <linux/mmc/host.h>
35 #include <linux/mmc/mmc.h>
36 #include <linux/mmc/sd.h>
37 #include <linux/mmc/slot-gpio.h>
38 
39 #define CREATE_TRACE_POINTS
40 #include <trace/events/mmc.h>
41 
42 #include "core.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 /* If the device is not responding */
53 #define MMC_CORE_TIMEOUT_MS	(10 * 60 * 1000) /* 10 minute timeout */
54 
55 /*
56  * Background operations can take a long time, depending on the housekeeping
57  * operations the card has to perform.
58  */
59 #define MMC_BKOPS_MAX_TIMEOUT	(4 * 60 * 1000) /* max time to wait in ms */
60 
61 /* The max erase timeout, used when host->max_busy_timeout isn't specified */
62 #define MMC_ERASE_TIMEOUT_MS	(60 * 1000) /* 60 s */
63 
64 static const unsigned freqs[] = { 400000, 300000, 200000, 100000 };
65 
66 /*
67  * Enabling software CRCs on the data blocks can be a significant (30%)
68  * performance cost, and for other reasons may not always be desired.
69  * So we allow it it to be disabled.
70  */
71 bool use_spi_crc = 1;
72 module_param(use_spi_crc, bool, 0);
73 
mmc_schedule_delayed_work(struct delayed_work * work,unsigned long delay)74 static int mmc_schedule_delayed_work(struct delayed_work *work,
75 				     unsigned long delay)
76 {
77 	/*
78 	 * We use the system_freezable_wq, because of two reasons.
79 	 * First, it allows several works (not the same work item) to be
80 	 * executed simultaneously. Second, the queue becomes frozen when
81 	 * userspace becomes frozen during system PM.
82 	 */
83 	return queue_delayed_work(system_freezable_wq, work, delay);
84 }
85 
86 #ifdef CONFIG_FAIL_MMC_REQUEST
87 
88 /*
89  * Internal function. Inject random data errors.
90  * If mmc_data is NULL no errors are injected.
91  */
mmc_should_fail_request(struct mmc_host * host,struct mmc_request * mrq)92 static void mmc_should_fail_request(struct mmc_host *host,
93 				    struct mmc_request *mrq)
94 {
95 	struct mmc_command *cmd = mrq->cmd;
96 	struct mmc_data *data = mrq->data;
97 	static const int data_errors[] = {
98 		-ETIMEDOUT,
99 		-EILSEQ,
100 		-EIO,
101 	};
102 
103 	if (!data)
104 		return;
105 
106 	if (cmd->error || data->error ||
107 	    !should_fail(&host->fail_mmc_request, data->blksz * data->blocks))
108 		return;
109 
110 	data->error = data_errors[prandom_u32() % ARRAY_SIZE(data_errors)];
111 	data->bytes_xfered = (prandom_u32() % (data->bytes_xfered >> 9)) << 9;
112 }
113 
114 #else /* CONFIG_FAIL_MMC_REQUEST */
115 
mmc_should_fail_request(struct mmc_host * host,struct mmc_request * mrq)116 static inline void mmc_should_fail_request(struct mmc_host *host,
117 					   struct mmc_request *mrq)
118 {
119 }
120 
121 #endif /* CONFIG_FAIL_MMC_REQUEST */
122 
mmc_complete_cmd(struct mmc_request * mrq)123 static inline void mmc_complete_cmd(struct mmc_request *mrq)
124 {
125 	if (mrq->cap_cmd_during_tfr && !completion_done(&mrq->cmd_completion))
126 		complete_all(&mrq->cmd_completion);
127 }
128 
mmc_command_done(struct mmc_host * host,struct mmc_request * mrq)129 void mmc_command_done(struct mmc_host *host, struct mmc_request *mrq)
130 {
131 	if (!mrq->cap_cmd_during_tfr)
132 		return;
133 
134 	mmc_complete_cmd(mrq);
135 
136 	pr_debug("%s: cmd done, tfr ongoing (CMD%u)\n",
137 		 mmc_hostname(host), mrq->cmd->opcode);
138 }
139 EXPORT_SYMBOL(mmc_command_done);
140 
141 /**
142  *	mmc_request_done - finish processing an MMC request
143  *	@host: MMC host which completed request
144  *	@mrq: MMC request which request
145  *
146  *	MMC drivers should call this function when they have completed
147  *	their processing of a request.
148  */
mmc_request_done(struct mmc_host * host,struct mmc_request * mrq)149 void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
150 {
151 	struct mmc_command *cmd = mrq->cmd;
152 	int err = cmd->error;
153 
154 	/* Flag re-tuning needed on CRC errors */
155 	if ((cmd->opcode != MMC_SEND_TUNING_BLOCK &&
156 	    cmd->opcode != MMC_SEND_TUNING_BLOCK_HS200) &&
157 	    (err == -EILSEQ || (mrq->sbc && mrq->sbc->error == -EILSEQ) ||
158 	    (mrq->data && mrq->data->error == -EILSEQ) ||
159 	    (mrq->stop && mrq->stop->error == -EILSEQ)))
160 		mmc_retune_needed(host);
161 
162 	if (err && cmd->retries && mmc_host_is_spi(host)) {
163 		if (cmd->resp[0] & R1_SPI_ILLEGAL_COMMAND)
164 			cmd->retries = 0;
165 	}
166 
167 	if (host->ongoing_mrq == mrq)
168 		host->ongoing_mrq = NULL;
169 
170 	mmc_complete_cmd(mrq);
171 
172 	trace_mmc_request_done(host, mrq);
173 
174 	if (err && cmd->retries && !mmc_card_removed(host->card)) {
175 		/*
176 		 * Request starter must handle retries - see
177 		 * mmc_wait_for_req_done().
178 		 */
179 		if (mrq->done)
180 			mrq->done(mrq);
181 	} else {
182 		mmc_should_fail_request(host, mrq);
183 
184 		if (!host->ongoing_mrq)
185 			led_trigger_event(host->led, LED_OFF);
186 
187 		if (mrq->sbc) {
188 			pr_debug("%s: req done <CMD%u>: %d: %08x %08x %08x %08x\n",
189 				mmc_hostname(host), mrq->sbc->opcode,
190 				mrq->sbc->error,
191 				mrq->sbc->resp[0], mrq->sbc->resp[1],
192 				mrq->sbc->resp[2], mrq->sbc->resp[3]);
193 		}
194 
195 		pr_debug("%s: req done (CMD%u): %d: %08x %08x %08x %08x\n",
196 			mmc_hostname(host), cmd->opcode, err,
197 			cmd->resp[0], cmd->resp[1],
198 			cmd->resp[2], cmd->resp[3]);
199 
200 		if (mrq->data) {
201 			pr_debug("%s:     %d bytes transferred: %d\n",
202 				mmc_hostname(host),
203 				mrq->data->bytes_xfered, mrq->data->error);
204 #ifdef CONFIG_BLOCK
205 			if (mrq->lat_hist_enabled) {
206 				ktime_t completion;
207 				u_int64_t delta_us;
208 
209 				completion = ktime_get();
210 				delta_us = ktime_us_delta(completion,
211 							  mrq->io_start);
212 				blk_update_latency_hist(
213 					(mrq->data->flags & MMC_DATA_READ) ?
214 					&host->io_lat_read :
215 					&host->io_lat_write, delta_us);
216 			}
217 #endif
218 		}
219 
220 		if (mrq->stop) {
221 			pr_debug("%s:     (CMD%u): %d: %08x %08x %08x %08x\n",
222 				mmc_hostname(host), mrq->stop->opcode,
223 				mrq->stop->error,
224 				mrq->stop->resp[0], mrq->stop->resp[1],
225 				mrq->stop->resp[2], mrq->stop->resp[3]);
226 		}
227 
228 		if (mrq->done)
229 			mrq->done(mrq);
230 	}
231 }
232 
233 EXPORT_SYMBOL(mmc_request_done);
234 
__mmc_start_request(struct mmc_host * host,struct mmc_request * mrq)235 static void __mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
236 {
237 	int err;
238 
239 	/* Assumes host controller has been runtime resumed by mmc_claim_host */
240 	err = mmc_retune(host);
241 	if (err) {
242 		mrq->cmd->error = err;
243 		mmc_request_done(host, mrq);
244 		return;
245 	}
246 
247 	/*
248 	 * For sdio rw commands we must wait for card busy otherwise some
249 	 * sdio devices won't work properly.
250 	 */
251 	if (mmc_is_io_op(mrq->cmd->opcode) && host->ops->card_busy) {
252 		int tries = 500; /* Wait aprox 500ms at maximum */
253 
254 		while (host->ops->card_busy(host) && --tries)
255 			mmc_delay(1);
256 
257 		if (tries == 0) {
258 			mrq->cmd->error = -EBUSY;
259 			mmc_request_done(host, mrq);
260 			return;
261 		}
262 	}
263 
264 	if (mrq->cap_cmd_during_tfr) {
265 		host->ongoing_mrq = mrq;
266 		/*
267 		 * Retry path could come through here without having waiting on
268 		 * cmd_completion, so ensure it is reinitialised.
269 		 */
270 		reinit_completion(&mrq->cmd_completion);
271 	}
272 
273 	trace_mmc_request_start(host, mrq);
274 
275 	host->ops->request(host, mrq);
276 }
277 
mmc_start_request(struct mmc_host * host,struct mmc_request * mrq)278 static int mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
279 {
280 #ifdef CONFIG_MMC_DEBUG
281 	unsigned int i, sz;
282 	struct scatterlist *sg;
283 #endif
284 	mmc_retune_hold(host);
285 
286 	if (mmc_card_removed(host->card))
287 		return -ENOMEDIUM;
288 
289 	if (mrq->sbc) {
290 		pr_debug("<%s: starting CMD%u arg %08x flags %08x>\n",
291 			 mmc_hostname(host), mrq->sbc->opcode,
292 			 mrq->sbc->arg, mrq->sbc->flags);
293 	}
294 
295 	pr_debug("%s: starting CMD%u arg %08x flags %08x\n",
296 		 mmc_hostname(host), mrq->cmd->opcode,
297 		 mrq->cmd->arg, mrq->cmd->flags);
298 
299 	if (mrq->data) {
300 		pr_debug("%s:     blksz %d blocks %d flags %08x "
301 			"tsac %d ms nsac %d\n",
302 			mmc_hostname(host), mrq->data->blksz,
303 			mrq->data->blocks, mrq->data->flags,
304 			mrq->data->timeout_ns / 1000000,
305 			mrq->data->timeout_clks);
306 	}
307 
308 	if (mrq->stop) {
309 		pr_debug("%s:     CMD%u arg %08x flags %08x\n",
310 			 mmc_hostname(host), mrq->stop->opcode,
311 			 mrq->stop->arg, mrq->stop->flags);
312 	}
313 
314 	WARN_ON(!host->claimed);
315 
316 	mrq->cmd->error = 0;
317 	mrq->cmd->mrq = mrq;
318 	if (mrq->sbc) {
319 		mrq->sbc->error = 0;
320 		mrq->sbc->mrq = mrq;
321 	}
322 	if (mrq->data) {
323 		BUG_ON(mrq->data->blksz > host->max_blk_size);
324 		BUG_ON(mrq->data->blocks > host->max_blk_count);
325 		BUG_ON(mrq->data->blocks * mrq->data->blksz >
326 			host->max_req_size);
327 
328 #ifdef CONFIG_MMC_DEBUG
329 		sz = 0;
330 		for_each_sg(mrq->data->sg, sg, mrq->data->sg_len, i)
331 			sz += sg->length;
332 		BUG_ON(sz != mrq->data->blocks * mrq->data->blksz);
333 #endif
334 
335 		mrq->cmd->data = mrq->data;
336 		mrq->data->error = 0;
337 		mrq->data->mrq = mrq;
338 		if (mrq->stop) {
339 			mrq->data->stop = mrq->stop;
340 			mrq->stop->error = 0;
341 			mrq->stop->mrq = mrq;
342 		}
343 	}
344 	led_trigger_event(host->led, LED_FULL);
345 	__mmc_start_request(host, mrq);
346 
347 	return 0;
348 }
349 
350 /**
351  *	mmc_start_bkops - start BKOPS for supported cards
352  *	@card: MMC card to start BKOPS
353  *	@form_exception: A flag to indicate if this function was
354  *			 called due to an exception raised by the card
355  *
356  *	Start background operations whenever requested.
357  *	When the urgent BKOPS bit is set in a R1 command response
358  *	then background operations should be started immediately.
359 */
mmc_start_bkops(struct mmc_card * card,bool from_exception)360 void mmc_start_bkops(struct mmc_card *card, bool from_exception)
361 {
362 	int err;
363 	int timeout;
364 	bool use_busy_signal;
365 
366 	BUG_ON(!card);
367 
368 	if (!card->ext_csd.man_bkops_en || mmc_card_doing_bkops(card))
369 		return;
370 
371 	err = mmc_read_bkops_status(card);
372 	if (err) {
373 		pr_err("%s: Failed to read bkops status: %d\n",
374 		       mmc_hostname(card->host), err);
375 		return;
376 	}
377 
378 	if (!card->ext_csd.raw_bkops_status)
379 		return;
380 
381 	if (card->ext_csd.raw_bkops_status < EXT_CSD_BKOPS_LEVEL_2 &&
382 	    from_exception)
383 		return;
384 
385 	mmc_claim_host(card->host);
386 	if (card->ext_csd.raw_bkops_status >= EXT_CSD_BKOPS_LEVEL_2) {
387 		timeout = MMC_BKOPS_MAX_TIMEOUT;
388 		use_busy_signal = true;
389 	} else {
390 		timeout = 0;
391 		use_busy_signal = false;
392 	}
393 
394 	mmc_retune_hold(card->host);
395 
396 	err = __mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
397 			EXT_CSD_BKOPS_START, 1, timeout,
398 			use_busy_signal, true, false);
399 	if (err) {
400 		pr_warn("%s: Error %d starting bkops\n",
401 			mmc_hostname(card->host), err);
402 		mmc_retune_release(card->host);
403 		goto out;
404 	}
405 
406 	/*
407 	 * For urgent bkops status (LEVEL_2 and more)
408 	 * bkops executed synchronously, otherwise
409 	 * the operation is in progress
410 	 */
411 	if (!use_busy_signal)
412 		mmc_card_set_doing_bkops(card);
413 	else
414 		mmc_retune_release(card->host);
415 out:
416 	mmc_release_host(card->host);
417 }
418 EXPORT_SYMBOL(mmc_start_bkops);
419 
420 /*
421  * mmc_wait_data_done() - done callback for data request
422  * @mrq: done data request
423  *
424  * Wakes up mmc context, passed as a callback to host controller driver
425  */
mmc_wait_data_done(struct mmc_request * mrq)426 static void mmc_wait_data_done(struct mmc_request *mrq)
427 {
428 	struct mmc_context_info *context_info = &mrq->host->context_info;
429 
430 	context_info->is_done_rcv = true;
431 	wake_up_interruptible(&context_info->wait);
432 }
433 
mmc_wait_done(struct mmc_request * mrq)434 static void mmc_wait_done(struct mmc_request *mrq)
435 {
436 	complete(&mrq->completion);
437 }
438 
mmc_wait_ongoing_tfr_cmd(struct mmc_host * host)439 static inline void mmc_wait_ongoing_tfr_cmd(struct mmc_host *host)
440 {
441 	struct mmc_request *ongoing_mrq = READ_ONCE(host->ongoing_mrq);
442 
443 	/*
444 	 * If there is an ongoing transfer, wait for the command line to become
445 	 * available.
446 	 */
447 	if (ongoing_mrq && !completion_done(&ongoing_mrq->cmd_completion))
448 		wait_for_completion(&ongoing_mrq->cmd_completion);
449 }
450 
451 /*
452  *__mmc_start_data_req() - starts data request
453  * @host: MMC host to start the request
454  * @mrq: data request to start
455  *
456  * Sets the done callback to be called when request is completed by the card.
457  * Starts data mmc request execution
458  * If an ongoing transfer is already in progress, wait for the command line
459  * to become available before sending another command.
460  */
__mmc_start_data_req(struct mmc_host * host,struct mmc_request * mrq)461 static int __mmc_start_data_req(struct mmc_host *host, struct mmc_request *mrq)
462 {
463 	int err;
464 
465 	mmc_wait_ongoing_tfr_cmd(host);
466 
467 	mrq->done = mmc_wait_data_done;
468 	mrq->host = host;
469 
470 	init_completion(&mrq->cmd_completion);
471 
472 	err = mmc_start_request(host, mrq);
473 	if (err) {
474 		mrq->cmd->error = err;
475 		mmc_complete_cmd(mrq);
476 		mmc_wait_data_done(mrq);
477 	}
478 
479 	return err;
480 }
481 
__mmc_start_req(struct mmc_host * host,struct mmc_request * mrq)482 static int __mmc_start_req(struct mmc_host *host, struct mmc_request *mrq)
483 {
484 	int err;
485 
486 	mmc_wait_ongoing_tfr_cmd(host);
487 
488 	init_completion(&mrq->completion);
489 	mrq->done = mmc_wait_done;
490 
491 	init_completion(&mrq->cmd_completion);
492 
493 	err = mmc_start_request(host, mrq);
494 	if (err) {
495 		mrq->cmd->error = err;
496 		mmc_complete_cmd(mrq);
497 		complete(&mrq->completion);
498 	}
499 
500 	return err;
501 }
502 
503 /*
504  * mmc_wait_for_data_req_done() - wait for request completed
505  * @host: MMC host to prepare the command.
506  * @mrq: MMC request to wait for
507  *
508  * Blocks MMC context till host controller will ack end of data request
509  * execution or new request notification arrives from the block layer.
510  * Handles command retries.
511  *
512  * Returns enum mmc_blk_status after checking errors.
513  */
mmc_wait_for_data_req_done(struct mmc_host * host,struct mmc_request * mrq,struct mmc_async_req * next_req)514 static int mmc_wait_for_data_req_done(struct mmc_host *host,
515 				      struct mmc_request *mrq,
516 				      struct mmc_async_req *next_req)
517 {
518 	struct mmc_command *cmd;
519 	struct mmc_context_info *context_info = &host->context_info;
520 	int err;
521 	unsigned long flags;
522 
523 	while (1) {
524 		wait_event_interruptible(context_info->wait,
525 				(context_info->is_done_rcv ||
526 				 context_info->is_new_req));
527 		spin_lock_irqsave(&context_info->lock, flags);
528 		context_info->is_waiting_last_req = false;
529 		spin_unlock_irqrestore(&context_info->lock, flags);
530 		if (context_info->is_done_rcv) {
531 			context_info->is_done_rcv = false;
532 			context_info->is_new_req = false;
533 			cmd = mrq->cmd;
534 
535 			if (!cmd->error || !cmd->retries ||
536 			    mmc_card_removed(host->card)) {
537 				err = host->areq->err_check(host->card,
538 							    host->areq);
539 				break; /* return err */
540 			} else {
541 				mmc_retune_recheck(host);
542 				pr_info("%s: req failed (CMD%u): %d, retrying...\n",
543 					mmc_hostname(host),
544 					cmd->opcode, cmd->error);
545 				cmd->retries--;
546 				cmd->error = 0;
547 				__mmc_start_request(host, mrq);
548 				continue; /* wait for done/new event again */
549 			}
550 		} else if (context_info->is_new_req) {
551 			context_info->is_new_req = false;
552 			if (!next_req)
553 				return MMC_BLK_NEW_REQUEST;
554 		}
555 	}
556 	mmc_retune_release(host);
557 	return err;
558 }
559 
mmc_wait_for_req_done(struct mmc_host * host,struct mmc_request * mrq)560 void mmc_wait_for_req_done(struct mmc_host *host, struct mmc_request *mrq)
561 {
562 	struct mmc_command *cmd;
563 
564 	while (1) {
565 		wait_for_completion(&mrq->completion);
566 
567 		cmd = mrq->cmd;
568 
569 		/*
570 		 * If host has timed out waiting for the sanitize
571 		 * to complete, card might be still in programming state
572 		 * so let's try to bring the card out of programming
573 		 * state.
574 		 */
575 		if (cmd->sanitize_busy && cmd->error == -ETIMEDOUT) {
576 			if (!mmc_interrupt_hpi(host->card)) {
577 				pr_warn("%s: %s: Interrupted sanitize\n",
578 					mmc_hostname(host), __func__);
579 				cmd->error = 0;
580 				break;
581 			} else {
582 				pr_err("%s: %s: Failed to interrupt sanitize\n",
583 				       mmc_hostname(host), __func__);
584 			}
585 		}
586 		if (!cmd->error || !cmd->retries ||
587 		    mmc_card_removed(host->card))
588 			break;
589 
590 		mmc_retune_recheck(host);
591 
592 		pr_debug("%s: req failed (CMD%u): %d, retrying...\n",
593 			 mmc_hostname(host), cmd->opcode, cmd->error);
594 		cmd->retries--;
595 		cmd->error = 0;
596 		__mmc_start_request(host, mrq);
597 	}
598 
599 	mmc_retune_release(host);
600 }
601 EXPORT_SYMBOL(mmc_wait_for_req_done);
602 
603 /**
604  *	mmc_is_req_done - Determine if a 'cap_cmd_during_tfr' request is done
605  *	@host: MMC host
606  *	@mrq: MMC request
607  *
608  *	mmc_is_req_done() is used with requests that have
609  *	mrq->cap_cmd_during_tfr = true. mmc_is_req_done() must be called after
610  *	starting a request and before waiting for it to complete. That is,
611  *	either in between calls to mmc_start_req(), or after mmc_wait_for_req()
612  *	and before mmc_wait_for_req_done(). If it is called at other times the
613  *	result is not meaningful.
614  */
mmc_is_req_done(struct mmc_host * host,struct mmc_request * mrq)615 bool mmc_is_req_done(struct mmc_host *host, struct mmc_request *mrq)
616 {
617 	if (host->areq)
618 		return host->context_info.is_done_rcv;
619 	else
620 		return completion_done(&mrq->completion);
621 }
622 EXPORT_SYMBOL(mmc_is_req_done);
623 
624 /**
625  *	mmc_pre_req - Prepare for a new request
626  *	@host: MMC host to prepare command
627  *	@mrq: MMC request to prepare for
628  *	@is_first_req: true if there is no previous started request
629  *                     that may run in parellel to this call, otherwise false
630  *
631  *	mmc_pre_req() is called in prior to mmc_start_req() to let
632  *	host prepare for the new request. Preparation of a request may be
633  *	performed while another request is running on the host.
634  */
mmc_pre_req(struct mmc_host * host,struct mmc_request * mrq,bool is_first_req)635 static void mmc_pre_req(struct mmc_host *host, struct mmc_request *mrq,
636 		 bool is_first_req)
637 {
638 	if (host->ops->pre_req)
639 		host->ops->pre_req(host, mrq, is_first_req);
640 }
641 
642 /**
643  *	mmc_post_req - Post process a completed request
644  *	@host: MMC host to post process command
645  *	@mrq: MMC request to post process for
646  *	@err: Error, if non zero, clean up any resources made in pre_req
647  *
648  *	Let the host post process a completed request. Post processing of
649  *	a request may be performed while another reuqest is running.
650  */
mmc_post_req(struct mmc_host * host,struct mmc_request * mrq,int err)651 static void mmc_post_req(struct mmc_host *host, struct mmc_request *mrq,
652 			 int err)
653 {
654 	if (host->ops->post_req)
655 		host->ops->post_req(host, mrq, err);
656 }
657 
658 /**
659  *	mmc_start_req - start a non-blocking request
660  *	@host: MMC host to start command
661  *	@areq: async request to start
662  *	@error: out parameter returns 0 for success, otherwise non zero
663  *
664  *	Start a new MMC custom command request for a host.
665  *	If there is on ongoing async request wait for completion
666  *	of that request and start the new one and return.
667  *	Does not wait for the new request to complete.
668  *
669  *      Returns the completed request, NULL in case of none completed.
670  *	Wait for the an ongoing request (previoulsy started) to complete and
671  *	return the completed request. If there is no ongoing request, NULL
672  *	is returned without waiting. NULL is not an error condition.
673  */
mmc_start_req(struct mmc_host * host,struct mmc_async_req * areq,int * error)674 struct mmc_async_req *mmc_start_req(struct mmc_host *host,
675 				    struct mmc_async_req *areq, int *error)
676 {
677 	int err = 0;
678 	int start_err = 0;
679 	struct mmc_async_req *data = host->areq;
680 
681 	/* Prepare a new request */
682 	if (areq)
683 		mmc_pre_req(host, areq->mrq, !host->areq);
684 
685 	if (host->areq) {
686 		err = mmc_wait_for_data_req_done(host, host->areq->mrq,	areq);
687 		if (err == MMC_BLK_NEW_REQUEST) {
688 			if (error)
689 				*error = err;
690 			/*
691 			 * The previous request was not completed,
692 			 * nothing to return
693 			 */
694 			return NULL;
695 		}
696 		/*
697 		 * Check BKOPS urgency for each R1 response
698 		 */
699 		if (host->card && mmc_card_mmc(host->card) &&
700 		    ((mmc_resp_type(host->areq->mrq->cmd) == MMC_RSP_R1) ||
701 		     (mmc_resp_type(host->areq->mrq->cmd) == MMC_RSP_R1B)) &&
702 		    (host->areq->mrq->cmd->resp[0] & R1_EXCEPTION_EVENT)) {
703 
704 			/* Cancel the prepared request */
705 			if (areq)
706 				mmc_post_req(host, areq->mrq, -EINVAL);
707 
708 			mmc_start_bkops(host->card, true);
709 
710 			/* prepare the request again */
711 			if (areq)
712 				mmc_pre_req(host, areq->mrq, !host->areq);
713 		}
714 	}
715 
716 	if (!err && areq) {
717 #ifdef CONFIG_BLOCK
718 		if (host->latency_hist_enabled) {
719 			areq->mrq->io_start = ktime_get();
720 			areq->mrq->lat_hist_enabled = 1;
721 		} else
722 			areq->mrq->lat_hist_enabled = 0;
723 #endif
724 		start_err = __mmc_start_data_req(host, areq->mrq);
725 	}
726 
727 	if (host->areq)
728 		mmc_post_req(host, host->areq->mrq, 0);
729 
730 	 /* Cancel a prepared request if it was not started. */
731 	if ((err || start_err) && areq)
732 		mmc_post_req(host, areq->mrq, -EINVAL);
733 
734 	if (err)
735 		host->areq = NULL;
736 	else
737 		host->areq = areq;
738 
739 	if (error)
740 		*error = err;
741 	return data;
742 }
743 EXPORT_SYMBOL(mmc_start_req);
744 
745 /**
746  *	mmc_wait_for_req - start a request and wait for completion
747  *	@host: MMC host to start command
748  *	@mrq: MMC request to start
749  *
750  *	Start a new MMC custom command request for a host, and wait
751  *	for the command to complete. In the case of 'cap_cmd_during_tfr'
752  *	requests, the transfer is ongoing and the caller can issue further
753  *	commands that do not use the data lines, and then wait by calling
754  *	mmc_wait_for_req_done().
755  *	Does not attempt to parse the response.
756  */
mmc_wait_for_req(struct mmc_host * host,struct mmc_request * mrq)757 void mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq)
758 {
759 	__mmc_start_req(host, mrq);
760 
761 	if (!mrq->cap_cmd_during_tfr)
762 		mmc_wait_for_req_done(host, mrq);
763 }
764 EXPORT_SYMBOL(mmc_wait_for_req);
765 
766 /**
767  *	mmc_interrupt_hpi - Issue for High priority Interrupt
768  *	@card: the MMC card associated with the HPI transfer
769  *
770  *	Issued High Priority Interrupt, and check for card status
771  *	until out-of prg-state.
772  */
mmc_interrupt_hpi(struct mmc_card * card)773 int mmc_interrupt_hpi(struct mmc_card *card)
774 {
775 	int err;
776 	u32 status;
777 	unsigned long prg_wait;
778 
779 	BUG_ON(!card);
780 
781 	if (!card->ext_csd.hpi_en) {
782 		pr_info("%s: HPI enable bit unset\n", mmc_hostname(card->host));
783 		return 1;
784 	}
785 
786 	mmc_claim_host(card->host);
787 	err = mmc_send_status(card, &status);
788 	if (err) {
789 		pr_err("%s: Get card status fail\n", mmc_hostname(card->host));
790 		goto out;
791 	}
792 
793 	switch (R1_CURRENT_STATE(status)) {
794 	case R1_STATE_IDLE:
795 	case R1_STATE_READY:
796 	case R1_STATE_STBY:
797 	case R1_STATE_TRAN:
798 		/*
799 		 * In idle and transfer states, HPI is not needed and the caller
800 		 * can issue the next intended command immediately
801 		 */
802 		goto out;
803 	case R1_STATE_PRG:
804 		break;
805 	default:
806 		/* In all other states, it's illegal to issue HPI */
807 		pr_debug("%s: HPI cannot be sent. Card state=%d\n",
808 			mmc_hostname(card->host), R1_CURRENT_STATE(status));
809 		err = -EINVAL;
810 		goto out;
811 	}
812 
813 	err = mmc_send_hpi_cmd(card, &status);
814 	if (err)
815 		goto out;
816 
817 	prg_wait = jiffies + msecs_to_jiffies(card->ext_csd.out_of_int_time);
818 	do {
819 		err = mmc_send_status(card, &status);
820 
821 		if (!err && R1_CURRENT_STATE(status) == R1_STATE_TRAN)
822 			break;
823 		if (time_after(jiffies, prg_wait))
824 			err = -ETIMEDOUT;
825 	} while (!err);
826 
827 out:
828 	mmc_release_host(card->host);
829 	return err;
830 }
831 EXPORT_SYMBOL(mmc_interrupt_hpi);
832 
833 /**
834  *	mmc_wait_for_cmd - start a command and wait for completion
835  *	@host: MMC host to start command
836  *	@cmd: MMC command to start
837  *	@retries: maximum number of retries
838  *
839  *	Start a new MMC command for a host, and wait for the command
840  *	to complete.  Return any error that occurred while the command
841  *	was executing.  Do not attempt to parse the response.
842  */
mmc_wait_for_cmd(struct mmc_host * host,struct mmc_command * cmd,int retries)843 int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries)
844 {
845 	struct mmc_request mrq = {NULL};
846 
847 	WARN_ON(!host->claimed);
848 
849 	memset(cmd->resp, 0, sizeof(cmd->resp));
850 	cmd->retries = retries;
851 
852 	mrq.cmd = cmd;
853 	cmd->data = NULL;
854 
855 	mmc_wait_for_req(host, &mrq);
856 
857 	return cmd->error;
858 }
859 
860 EXPORT_SYMBOL(mmc_wait_for_cmd);
861 
862 /**
863  *	mmc_stop_bkops - stop ongoing BKOPS
864  *	@card: MMC card to check BKOPS
865  *
866  *	Send HPI command to stop ongoing background operations to
867  *	allow rapid servicing of foreground operations, e.g. read/
868  *	writes. Wait until the card comes out of the programming state
869  *	to avoid errors in servicing read/write requests.
870  */
mmc_stop_bkops(struct mmc_card * card)871 int mmc_stop_bkops(struct mmc_card *card)
872 {
873 	int err = 0;
874 
875 	BUG_ON(!card);
876 	err = mmc_interrupt_hpi(card);
877 
878 	/*
879 	 * If err is EINVAL, we can't issue an HPI.
880 	 * It should complete the BKOPS.
881 	 */
882 	if (!err || (err == -EINVAL)) {
883 		mmc_card_clr_doing_bkops(card);
884 		mmc_retune_release(card->host);
885 		err = 0;
886 	}
887 
888 	return err;
889 }
890 EXPORT_SYMBOL(mmc_stop_bkops);
891 
mmc_read_bkops_status(struct mmc_card * card)892 int mmc_read_bkops_status(struct mmc_card *card)
893 {
894 	int err;
895 	u8 *ext_csd;
896 
897 	mmc_claim_host(card->host);
898 	err = mmc_get_ext_csd(card, &ext_csd);
899 	mmc_release_host(card->host);
900 	if (err)
901 		return err;
902 
903 	card->ext_csd.raw_bkops_status = ext_csd[EXT_CSD_BKOPS_STATUS];
904 	card->ext_csd.raw_exception_status = ext_csd[EXT_CSD_EXP_EVENTS_STATUS];
905 	kfree(ext_csd);
906 	return 0;
907 }
908 EXPORT_SYMBOL(mmc_read_bkops_status);
909 
910 /**
911  *	mmc_set_data_timeout - set the timeout for a data command
912  *	@data: data phase for command
913  *	@card: the MMC card associated with the data transfer
914  *
915  *	Computes the data timeout parameters according to the
916  *	correct algorithm given the card type.
917  */
mmc_set_data_timeout(struct mmc_data * data,const struct mmc_card * card)918 void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card)
919 {
920 	unsigned int mult;
921 
922 	/*
923 	 * SDIO cards only define an upper 1 s limit on access.
924 	 */
925 	if (mmc_card_sdio(card)) {
926 		data->timeout_ns = 1000000000;
927 		data->timeout_clks = 0;
928 		return;
929 	}
930 
931 	/*
932 	 * SD cards use a 100 multiplier rather than 10
933 	 */
934 	mult = mmc_card_sd(card) ? 100 : 10;
935 
936 	/*
937 	 * Scale up the multiplier (and therefore the timeout) by
938 	 * the r2w factor for writes.
939 	 */
940 	if (data->flags & MMC_DATA_WRITE)
941 		mult <<= card->csd.r2w_factor;
942 
943 	data->timeout_ns = card->csd.tacc_ns * mult;
944 	data->timeout_clks = card->csd.tacc_clks * mult;
945 
946 	/*
947 	 * SD cards also have an upper limit on the timeout.
948 	 */
949 	if (mmc_card_sd(card)) {
950 		unsigned int timeout_us, limit_us;
951 
952 		timeout_us = data->timeout_ns / 1000;
953 		if (card->host->ios.clock)
954 			timeout_us += data->timeout_clks * 1000 /
955 				(card->host->ios.clock / 1000);
956 
957 		if (data->flags & MMC_DATA_WRITE)
958 			/*
959 			 * The MMC spec "It is strongly recommended
960 			 * for hosts to implement more than 500ms
961 			 * timeout value even if the card indicates
962 			 * the 250ms maximum busy length."  Even the
963 			 * previous value of 300ms is known to be
964 			 * insufficient for some cards.
965 			 */
966 			limit_us = 3000000;
967 		else
968 			limit_us = 100000;
969 
970 		/*
971 		 * SDHC cards always use these fixed values.
972 		 */
973 		if (timeout_us > limit_us || mmc_card_blockaddr(card)) {
974 			data->timeout_ns = limit_us * 1000;
975 			data->timeout_clks = 0;
976 		}
977 
978 		/* assign limit value if invalid */
979 		if (timeout_us == 0)
980 			data->timeout_ns = limit_us * 1000;
981 	}
982 
983 	/*
984 	 * Some cards require longer data read timeout than indicated in CSD.
985 	 * Address this by setting the read timeout to a "reasonably high"
986 	 * value. For the cards tested, 600ms has proven enough. If necessary,
987 	 * this value can be increased if other problematic cards require this.
988 	 */
989 	if (mmc_card_long_read_time(card) && data->flags & MMC_DATA_READ) {
990 		data->timeout_ns = 600000000;
991 		data->timeout_clks = 0;
992 	}
993 
994 	/*
995 	 * Some cards need very high timeouts if driven in SPI mode.
996 	 * The worst observed timeout was 900ms after writing a
997 	 * continuous stream of data until the internal logic
998 	 * overflowed.
999 	 */
1000 	if (mmc_host_is_spi(card->host)) {
1001 		if (data->flags & MMC_DATA_WRITE) {
1002 			if (data->timeout_ns < 1000000000)
1003 				data->timeout_ns = 1000000000;	/* 1s */
1004 		} else {
1005 			if (data->timeout_ns < 100000000)
1006 				data->timeout_ns =  100000000;	/* 100ms */
1007 		}
1008 	}
1009 }
1010 EXPORT_SYMBOL(mmc_set_data_timeout);
1011 
1012 /**
1013  *	mmc_align_data_size - pads a transfer size to a more optimal value
1014  *	@card: the MMC card associated with the data transfer
1015  *	@sz: original transfer size
1016  *
1017  *	Pads the original data size with a number of extra bytes in
1018  *	order to avoid controller bugs and/or performance hits
1019  *	(e.g. some controllers revert to PIO for certain sizes).
1020  *
1021  *	Returns the improved size, which might be unmodified.
1022  *
1023  *	Note that this function is only relevant when issuing a
1024  *	single scatter gather entry.
1025  */
mmc_align_data_size(struct mmc_card * card,unsigned int sz)1026 unsigned int mmc_align_data_size(struct mmc_card *card, unsigned int sz)
1027 {
1028 	/*
1029 	 * FIXME: We don't have a system for the controller to tell
1030 	 * the core about its problems yet, so for now we just 32-bit
1031 	 * align the size.
1032 	 */
1033 	sz = ((sz + 3) / 4) * 4;
1034 
1035 	return sz;
1036 }
1037 EXPORT_SYMBOL(mmc_align_data_size);
1038 
1039 /**
1040  *	__mmc_claim_host - exclusively claim a host
1041  *	@host: mmc host to claim
1042  *	@abort: whether or not the operation should be aborted
1043  *
1044  *	Claim a host for a set of operations.  If @abort is non null and
1045  *	dereference a non-zero value then this will return prematurely with
1046  *	that non-zero value without acquiring the lock.  Returns zero
1047  *	with the lock held otherwise.
1048  */
__mmc_claim_host(struct mmc_host * host,atomic_t * abort)1049 int __mmc_claim_host(struct mmc_host *host, atomic_t *abort)
1050 {
1051 	DECLARE_WAITQUEUE(wait, current);
1052 	unsigned long flags;
1053 	int stop;
1054 	bool pm = false;
1055 
1056 	might_sleep();
1057 
1058 	add_wait_queue(&host->wq, &wait);
1059 	spin_lock_irqsave(&host->lock, flags);
1060 	while (1) {
1061 		set_current_state(TASK_UNINTERRUPTIBLE);
1062 		stop = abort ? atomic_read(abort) : 0;
1063 		if (stop || !host->claimed || host->claimer == current)
1064 			break;
1065 		spin_unlock_irqrestore(&host->lock, flags);
1066 		schedule();
1067 		spin_lock_irqsave(&host->lock, flags);
1068 	}
1069 	set_current_state(TASK_RUNNING);
1070 	if (!stop) {
1071 		host->claimed = 1;
1072 		host->claimer = current;
1073 		host->claim_cnt += 1;
1074 		if (host->claim_cnt == 1)
1075 			pm = true;
1076 	} else
1077 		wake_up(&host->wq);
1078 	spin_unlock_irqrestore(&host->lock, flags);
1079 	remove_wait_queue(&host->wq, &wait);
1080 
1081 	if (pm)
1082 		pm_runtime_get_sync(mmc_dev(host));
1083 
1084 	return stop;
1085 }
1086 EXPORT_SYMBOL(__mmc_claim_host);
1087 
1088 /**
1089  *	mmc_release_host - release a host
1090  *	@host: mmc host to release
1091  *
1092  *	Release a MMC host, allowing others to claim the host
1093  *	for their operations.
1094  */
mmc_release_host(struct mmc_host * host)1095 void mmc_release_host(struct mmc_host *host)
1096 {
1097 	unsigned long flags;
1098 
1099 	WARN_ON(!host->claimed);
1100 
1101 	spin_lock_irqsave(&host->lock, flags);
1102 	if (--host->claim_cnt) {
1103 		/* Release for nested claim */
1104 		spin_unlock_irqrestore(&host->lock, flags);
1105 	} else {
1106 		host->claimed = 0;
1107 		host->claimer = NULL;
1108 		spin_unlock_irqrestore(&host->lock, flags);
1109 		wake_up(&host->wq);
1110 		pm_runtime_mark_last_busy(mmc_dev(host));
1111 		pm_runtime_put_autosuspend(mmc_dev(host));
1112 	}
1113 }
1114 EXPORT_SYMBOL(mmc_release_host);
1115 
1116 /*
1117  * This is a helper function, which fetches a runtime pm reference for the
1118  * card device and also claims the host.
1119  */
mmc_get_card(struct mmc_card * card)1120 void mmc_get_card(struct mmc_card *card)
1121 {
1122 	pm_runtime_get_sync(&card->dev);
1123 	mmc_claim_host(card->host);
1124 }
1125 EXPORT_SYMBOL(mmc_get_card);
1126 
1127 /*
1128  * This is a helper function, which releases the host and drops the runtime
1129  * pm reference for the card device.
1130  */
mmc_put_card(struct mmc_card * card)1131 void mmc_put_card(struct mmc_card *card)
1132 {
1133 	mmc_release_host(card->host);
1134 	pm_runtime_mark_last_busy(&card->dev);
1135 	pm_runtime_put_autosuspend(&card->dev);
1136 }
1137 EXPORT_SYMBOL(mmc_put_card);
1138 
1139 /*
1140  * Internal function that does the actual ios call to the host driver,
1141  * optionally printing some debug output.
1142  */
mmc_set_ios(struct mmc_host * host)1143 static inline void mmc_set_ios(struct mmc_host *host)
1144 {
1145 	struct mmc_ios *ios = &host->ios;
1146 
1147 	pr_debug("%s: clock %uHz busmode %u powermode %u cs %u Vdd %u "
1148 		"width %u timing %u\n",
1149 		 mmc_hostname(host), ios->clock, ios->bus_mode,
1150 		 ios->power_mode, ios->chip_select, ios->vdd,
1151 		 1 << ios->bus_width, ios->timing);
1152 
1153 	host->ops->set_ios(host, ios);
1154 }
1155 
1156 /*
1157  * Control chip select pin on a host.
1158  */
mmc_set_chip_select(struct mmc_host * host,int mode)1159 void mmc_set_chip_select(struct mmc_host *host, int mode)
1160 {
1161 	host->ios.chip_select = mode;
1162 	mmc_set_ios(host);
1163 }
1164 
1165 /*
1166  * Sets the host clock to the highest possible frequency that
1167  * is below "hz".
1168  */
mmc_set_clock(struct mmc_host * host,unsigned int hz)1169 void mmc_set_clock(struct mmc_host *host, unsigned int hz)
1170 {
1171 	WARN_ON(hz && hz < host->f_min);
1172 
1173 	if (hz > host->f_max)
1174 		hz = host->f_max;
1175 
1176 	host->ios.clock = hz;
1177 	mmc_set_ios(host);
1178 }
1179 
mmc_execute_tuning(struct mmc_card * card)1180 int mmc_execute_tuning(struct mmc_card *card)
1181 {
1182 	struct mmc_host *host = card->host;
1183 	u32 opcode;
1184 	int err;
1185 
1186 	if (!host->ops->execute_tuning)
1187 		return 0;
1188 
1189 	if (mmc_card_mmc(card))
1190 		opcode = MMC_SEND_TUNING_BLOCK_HS200;
1191 	else
1192 		opcode = MMC_SEND_TUNING_BLOCK;
1193 
1194 	err = host->ops->execute_tuning(host, opcode);
1195 
1196 	if (err)
1197 		pr_err("%s: tuning execution failed: %d\n",
1198 			mmc_hostname(host), err);
1199 	else
1200 		mmc_retune_enable(host);
1201 
1202 	return err;
1203 }
1204 
1205 /*
1206  * Change the bus mode (open drain/push-pull) of a host.
1207  */
mmc_set_bus_mode(struct mmc_host * host,unsigned int mode)1208 void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode)
1209 {
1210 	host->ios.bus_mode = mode;
1211 	mmc_set_ios(host);
1212 }
1213 
1214 /*
1215  * Change data bus width of a host.
1216  */
mmc_set_bus_width(struct mmc_host * host,unsigned int width)1217 void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
1218 {
1219 	host->ios.bus_width = width;
1220 	mmc_set_ios(host);
1221 }
1222 
1223 /*
1224  * Set initial state after a power cycle or a hw_reset.
1225  */
mmc_set_initial_state(struct mmc_host * host)1226 void mmc_set_initial_state(struct mmc_host *host)
1227 {
1228 	mmc_retune_disable(host);
1229 
1230 	if (mmc_host_is_spi(host))
1231 		host->ios.chip_select = MMC_CS_HIGH;
1232 	else
1233 		host->ios.chip_select = MMC_CS_DONTCARE;
1234 	host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
1235 	host->ios.bus_width = MMC_BUS_WIDTH_1;
1236 	host->ios.timing = MMC_TIMING_LEGACY;
1237 	host->ios.drv_type = 0;
1238 	host->ios.enhanced_strobe = false;
1239 
1240 	/*
1241 	 * Make sure we are in non-enhanced strobe mode before we
1242 	 * actually enable it in ext_csd.
1243 	 */
1244 	if ((host->caps2 & MMC_CAP2_HS400_ES) &&
1245 	     host->ops->hs400_enhanced_strobe)
1246 		host->ops->hs400_enhanced_strobe(host, &host->ios);
1247 
1248 	mmc_set_ios(host);
1249 }
1250 
1251 /**
1252  * mmc_vdd_to_ocrbitnum - Convert a voltage to the OCR bit number
1253  * @vdd:	voltage (mV)
1254  * @low_bits:	prefer low bits in boundary cases
1255  *
1256  * This function returns the OCR bit number according to the provided @vdd
1257  * value. If conversion is not possible a negative errno value returned.
1258  *
1259  * Depending on the @low_bits flag the function prefers low or high OCR bits
1260  * on boundary voltages. For example,
1261  * with @low_bits = true, 3300 mV translates to ilog2(MMC_VDD_32_33);
1262  * with @low_bits = false, 3300 mV translates to ilog2(MMC_VDD_33_34);
1263  *
1264  * Any value in the [1951:1999] range translates to the ilog2(MMC_VDD_20_21).
1265  */
mmc_vdd_to_ocrbitnum(int vdd,bool low_bits)1266 static int mmc_vdd_to_ocrbitnum(int vdd, bool low_bits)
1267 {
1268 	const int max_bit = ilog2(MMC_VDD_35_36);
1269 	int bit;
1270 
1271 	if (vdd < 1650 || vdd > 3600)
1272 		return -EINVAL;
1273 
1274 	if (vdd >= 1650 && vdd <= 1950)
1275 		return ilog2(MMC_VDD_165_195);
1276 
1277 	if (low_bits)
1278 		vdd -= 1;
1279 
1280 	/* Base 2000 mV, step 100 mV, bit's base 8. */
1281 	bit = (vdd - 2000) / 100 + 8;
1282 	if (bit > max_bit)
1283 		return max_bit;
1284 	return bit;
1285 }
1286 
1287 /**
1288  * mmc_vddrange_to_ocrmask - Convert a voltage range to the OCR mask
1289  * @vdd_min:	minimum voltage value (mV)
1290  * @vdd_max:	maximum voltage value (mV)
1291  *
1292  * This function returns the OCR mask bits according to the provided @vdd_min
1293  * and @vdd_max values. If conversion is not possible the function returns 0.
1294  *
1295  * Notes wrt boundary cases:
1296  * This function sets the OCR bits for all boundary voltages, for example
1297  * [3300:3400] range is translated to MMC_VDD_32_33 | MMC_VDD_33_34 |
1298  * MMC_VDD_34_35 mask.
1299  */
mmc_vddrange_to_ocrmask(int vdd_min,int vdd_max)1300 u32 mmc_vddrange_to_ocrmask(int vdd_min, int vdd_max)
1301 {
1302 	u32 mask = 0;
1303 
1304 	if (vdd_max < vdd_min)
1305 		return 0;
1306 
1307 	/* Prefer high bits for the boundary vdd_max values. */
1308 	vdd_max = mmc_vdd_to_ocrbitnum(vdd_max, false);
1309 	if (vdd_max < 0)
1310 		return 0;
1311 
1312 	/* Prefer low bits for the boundary vdd_min values. */
1313 	vdd_min = mmc_vdd_to_ocrbitnum(vdd_min, true);
1314 	if (vdd_min < 0)
1315 		return 0;
1316 
1317 	/* Fill the mask, from max bit to min bit. */
1318 	while (vdd_max >= vdd_min)
1319 		mask |= 1 << vdd_max--;
1320 
1321 	return mask;
1322 }
1323 EXPORT_SYMBOL(mmc_vddrange_to_ocrmask);
1324 
1325 #ifdef CONFIG_OF
1326 
1327 /**
1328  * mmc_of_parse_voltage - return mask of supported voltages
1329  * @np: The device node need to be parsed.
1330  * @mask: mask of voltages available for MMC/SD/SDIO
1331  *
1332  * Parse the "voltage-ranges" DT property, returning zero if it is not
1333  * found, negative errno if the voltage-range specification is invalid,
1334  * or one if the voltage-range is specified and successfully parsed.
1335  */
mmc_of_parse_voltage(struct device_node * np,u32 * mask)1336 int mmc_of_parse_voltage(struct device_node *np, u32 *mask)
1337 {
1338 	const u32 *voltage_ranges;
1339 	int num_ranges, i;
1340 
1341 	voltage_ranges = of_get_property(np, "voltage-ranges", &num_ranges);
1342 	num_ranges = num_ranges / sizeof(*voltage_ranges) / 2;
1343 	if (!voltage_ranges) {
1344 		pr_debug("%s: voltage-ranges unspecified\n", np->full_name);
1345 		return 0;
1346 	}
1347 	if (!num_ranges) {
1348 		pr_err("%s: voltage-ranges empty\n", np->full_name);
1349 		return -EINVAL;
1350 	}
1351 
1352 	for (i = 0; i < num_ranges; i++) {
1353 		const int j = i * 2;
1354 		u32 ocr_mask;
1355 
1356 		ocr_mask = mmc_vddrange_to_ocrmask(
1357 				be32_to_cpu(voltage_ranges[j]),
1358 				be32_to_cpu(voltage_ranges[j + 1]));
1359 		if (!ocr_mask) {
1360 			pr_err("%s: voltage-range #%d is invalid\n",
1361 				np->full_name, i);
1362 			return -EINVAL;
1363 		}
1364 		*mask |= ocr_mask;
1365 	}
1366 
1367 	return 1;
1368 }
1369 EXPORT_SYMBOL(mmc_of_parse_voltage);
1370 
1371 #endif /* CONFIG_OF */
1372 
mmc_of_get_func_num(struct device_node * node)1373 static int mmc_of_get_func_num(struct device_node *node)
1374 {
1375 	u32 reg;
1376 	int ret;
1377 
1378 	ret = of_property_read_u32(node, "reg", &reg);
1379 	if (ret < 0)
1380 		return ret;
1381 
1382 	return reg;
1383 }
1384 
mmc_of_find_child_device(struct mmc_host * host,unsigned func_num)1385 struct device_node *mmc_of_find_child_device(struct mmc_host *host,
1386 		unsigned func_num)
1387 {
1388 	struct device_node *node;
1389 
1390 	if (!host->parent || !host->parent->of_node)
1391 		return NULL;
1392 
1393 	for_each_child_of_node(host->parent->of_node, node) {
1394 		if (mmc_of_get_func_num(node) == func_num)
1395 			return node;
1396 	}
1397 
1398 	return NULL;
1399 }
1400 
1401 #ifdef CONFIG_REGULATOR
1402 
1403 /**
1404  * mmc_ocrbitnum_to_vdd - Convert a OCR bit number to its voltage
1405  * @vdd_bit:	OCR bit number
1406  * @min_uV:	minimum voltage value (mV)
1407  * @max_uV:	maximum voltage value (mV)
1408  *
1409  * This function returns the voltage range according to the provided OCR
1410  * bit number. If conversion is not possible a negative errno value returned.
1411  */
mmc_ocrbitnum_to_vdd(int vdd_bit,int * min_uV,int * max_uV)1412 static int mmc_ocrbitnum_to_vdd(int vdd_bit, int *min_uV, int *max_uV)
1413 {
1414 	int		tmp;
1415 
1416 	if (!vdd_bit)
1417 		return -EINVAL;
1418 
1419 	/*
1420 	 * REVISIT mmc_vddrange_to_ocrmask() may have set some
1421 	 * bits this regulator doesn't quite support ... don't
1422 	 * be too picky, most cards and regulators are OK with
1423 	 * a 0.1V range goof (it's a small error percentage).
1424 	 */
1425 	tmp = vdd_bit - ilog2(MMC_VDD_165_195);
1426 	if (tmp == 0) {
1427 		*min_uV = 1650 * 1000;
1428 		*max_uV = 1950 * 1000;
1429 	} else {
1430 		*min_uV = 1900 * 1000 + tmp * 100 * 1000;
1431 		*max_uV = *min_uV + 100 * 1000;
1432 	}
1433 
1434 	return 0;
1435 }
1436 
1437 /**
1438  * mmc_regulator_get_ocrmask - return mask of supported voltages
1439  * @supply: regulator to use
1440  *
1441  * This returns either a negative errno, or a mask of voltages that
1442  * can be provided to MMC/SD/SDIO devices using the specified voltage
1443  * regulator.  This would normally be called before registering the
1444  * MMC host adapter.
1445  */
mmc_regulator_get_ocrmask(struct regulator * supply)1446 int mmc_regulator_get_ocrmask(struct regulator *supply)
1447 {
1448 	int			result = 0;
1449 	int			count;
1450 	int			i;
1451 	int			vdd_uV;
1452 	int			vdd_mV;
1453 
1454 	count = regulator_count_voltages(supply);
1455 	if (count < 0)
1456 		return count;
1457 
1458 	for (i = 0; i < count; i++) {
1459 		vdd_uV = regulator_list_voltage(supply, i);
1460 		if (vdd_uV <= 0)
1461 			continue;
1462 
1463 		vdd_mV = vdd_uV / 1000;
1464 		result |= mmc_vddrange_to_ocrmask(vdd_mV, vdd_mV);
1465 	}
1466 
1467 	if (!result) {
1468 		vdd_uV = regulator_get_voltage(supply);
1469 		if (vdd_uV <= 0)
1470 			return vdd_uV;
1471 
1472 		vdd_mV = vdd_uV / 1000;
1473 		result = mmc_vddrange_to_ocrmask(vdd_mV, vdd_mV);
1474 	}
1475 
1476 	return result;
1477 }
1478 EXPORT_SYMBOL_GPL(mmc_regulator_get_ocrmask);
1479 
1480 /**
1481  * mmc_regulator_set_ocr - set regulator to match host->ios voltage
1482  * @mmc: the host to regulate
1483  * @supply: regulator to use
1484  * @vdd_bit: zero for power off, else a bit number (host->ios.vdd)
1485  *
1486  * Returns zero on success, else negative errno.
1487  *
1488  * MMC host drivers may use this to enable or disable a regulator using
1489  * a particular supply voltage.  This would normally be called from the
1490  * set_ios() method.
1491  */
mmc_regulator_set_ocr(struct mmc_host * mmc,struct regulator * supply,unsigned short vdd_bit)1492 int mmc_regulator_set_ocr(struct mmc_host *mmc,
1493 			struct regulator *supply,
1494 			unsigned short vdd_bit)
1495 {
1496 	int			result = 0;
1497 	int			min_uV, max_uV;
1498 
1499 	if (vdd_bit) {
1500 		mmc_ocrbitnum_to_vdd(vdd_bit, &min_uV, &max_uV);
1501 
1502 		result = regulator_set_voltage(supply, min_uV, max_uV);
1503 		if (result == 0 && !mmc->regulator_enabled) {
1504 			result = regulator_enable(supply);
1505 			if (!result)
1506 				mmc->regulator_enabled = true;
1507 		}
1508 	} else if (mmc->regulator_enabled) {
1509 		result = regulator_disable(supply);
1510 		if (result == 0)
1511 			mmc->regulator_enabled = false;
1512 	}
1513 
1514 	if (result)
1515 		dev_err(mmc_dev(mmc),
1516 			"could not set regulator OCR (%d)\n", result);
1517 	return result;
1518 }
1519 EXPORT_SYMBOL_GPL(mmc_regulator_set_ocr);
1520 
mmc_regulator_set_voltage_if_supported(struct regulator * regulator,int min_uV,int target_uV,int max_uV)1521 static int mmc_regulator_set_voltage_if_supported(struct regulator *regulator,
1522 						  int min_uV, int target_uV,
1523 						  int max_uV)
1524 {
1525 	/*
1526 	 * Check if supported first to avoid errors since we may try several
1527 	 * signal levels during power up and don't want to show errors.
1528 	 */
1529 	if (!regulator_is_supported_voltage(regulator, min_uV, max_uV))
1530 		return -EINVAL;
1531 
1532 	return regulator_set_voltage_triplet(regulator, min_uV, target_uV,
1533 					     max_uV);
1534 }
1535 
1536 /**
1537  * mmc_regulator_set_vqmmc - Set VQMMC as per the ios
1538  *
1539  * For 3.3V signaling, we try to match VQMMC to VMMC as closely as possible.
1540  * That will match the behavior of old boards where VQMMC and VMMC were supplied
1541  * by the same supply.  The Bus Operating conditions for 3.3V signaling in the
1542  * SD card spec also define VQMMC in terms of VMMC.
1543  * If this is not possible we'll try the full 2.7-3.6V of the spec.
1544  *
1545  * For 1.2V and 1.8V signaling we'll try to get as close as possible to the
1546  * requested voltage.  This is definitely a good idea for UHS where there's a
1547  * separate regulator on the card that's trying to make 1.8V and it's best if
1548  * we match.
1549  *
1550  * This function is expected to be used by a controller's
1551  * start_signal_voltage_switch() function.
1552  */
mmc_regulator_set_vqmmc(struct mmc_host * mmc,struct mmc_ios * ios)1553 int mmc_regulator_set_vqmmc(struct mmc_host *mmc, struct mmc_ios *ios)
1554 {
1555 	struct device *dev = mmc_dev(mmc);
1556 	int ret, volt, min_uV, max_uV;
1557 
1558 	/* If no vqmmc supply then we can't change the voltage */
1559 	if (IS_ERR(mmc->supply.vqmmc))
1560 		return -EINVAL;
1561 
1562 	switch (ios->signal_voltage) {
1563 	case MMC_SIGNAL_VOLTAGE_120:
1564 		return mmc_regulator_set_voltage_if_supported(mmc->supply.vqmmc,
1565 						1100000, 1200000, 1300000);
1566 	case MMC_SIGNAL_VOLTAGE_180:
1567 		return mmc_regulator_set_voltage_if_supported(mmc->supply.vqmmc,
1568 						1700000, 1800000, 1950000);
1569 	case MMC_SIGNAL_VOLTAGE_330:
1570 		ret = mmc_ocrbitnum_to_vdd(mmc->ios.vdd, &volt, &max_uV);
1571 		if (ret < 0)
1572 			return ret;
1573 
1574 		dev_dbg(dev, "%s: found vmmc voltage range of %d-%duV\n",
1575 			__func__, volt, max_uV);
1576 
1577 		min_uV = max(volt - 300000, 2700000);
1578 		max_uV = min(max_uV + 200000, 3600000);
1579 
1580 		/*
1581 		 * Due to a limitation in the current implementation of
1582 		 * regulator_set_voltage_triplet() which is taking the lowest
1583 		 * voltage possible if below the target, search for a suitable
1584 		 * voltage in two steps and try to stay close to vmmc
1585 		 * with a 0.3V tolerance at first.
1586 		 */
1587 		if (!mmc_regulator_set_voltage_if_supported(mmc->supply.vqmmc,
1588 						min_uV, volt, max_uV))
1589 			return 0;
1590 
1591 		return mmc_regulator_set_voltage_if_supported(mmc->supply.vqmmc,
1592 						2700000, volt, 3600000);
1593 	default:
1594 		return -EINVAL;
1595 	}
1596 }
1597 EXPORT_SYMBOL_GPL(mmc_regulator_set_vqmmc);
1598 
1599 #endif /* CONFIG_REGULATOR */
1600 
mmc_regulator_get_supply(struct mmc_host * mmc)1601 int mmc_regulator_get_supply(struct mmc_host *mmc)
1602 {
1603 	struct device *dev = mmc_dev(mmc);
1604 	int ret;
1605 
1606 	mmc->supply.vmmc = devm_regulator_get_optional(dev, "vmmc");
1607 	mmc->supply.vqmmc = devm_regulator_get_optional(dev, "vqmmc");
1608 
1609 	if (IS_ERR(mmc->supply.vmmc)) {
1610 		if (PTR_ERR(mmc->supply.vmmc) == -EPROBE_DEFER)
1611 			return -EPROBE_DEFER;
1612 		dev_dbg(dev, "No vmmc regulator found\n");
1613 	} else {
1614 		ret = mmc_regulator_get_ocrmask(mmc->supply.vmmc);
1615 		if (ret > 0)
1616 			mmc->ocr_avail = ret;
1617 		else
1618 			dev_warn(dev, "Failed getting OCR mask: %d\n", ret);
1619 	}
1620 
1621 	if (IS_ERR(mmc->supply.vqmmc)) {
1622 		if (PTR_ERR(mmc->supply.vqmmc) == -EPROBE_DEFER)
1623 			return -EPROBE_DEFER;
1624 		dev_dbg(dev, "No vqmmc regulator found\n");
1625 	}
1626 
1627 	return 0;
1628 }
1629 EXPORT_SYMBOL_GPL(mmc_regulator_get_supply);
1630 
1631 /*
1632  * Mask off any voltages we don't support and select
1633  * the lowest voltage
1634  */
mmc_select_voltage(struct mmc_host * host,u32 ocr)1635 u32 mmc_select_voltage(struct mmc_host *host, u32 ocr)
1636 {
1637 	int bit;
1638 
1639 	/*
1640 	 * Sanity check the voltages that the card claims to
1641 	 * support.
1642 	 */
1643 	if (ocr & 0x7F) {
1644 		dev_warn(mmc_dev(host),
1645 		"card claims to support voltages below defined range\n");
1646 		ocr &= ~0x7F;
1647 	}
1648 
1649 	ocr &= host->ocr_avail;
1650 	if (!ocr) {
1651 		dev_warn(mmc_dev(host), "no support for card's volts\n");
1652 		return 0;
1653 	}
1654 
1655 	if (host->caps2 & MMC_CAP2_FULL_PWR_CYCLE) {
1656 		bit = ffs(ocr) - 1;
1657 		ocr &= 3 << bit;
1658 		mmc_power_cycle(host, ocr);
1659 	} else {
1660 		bit = fls(ocr) - 1;
1661 		ocr &= 3 << bit;
1662 		if (bit != host->ios.vdd)
1663 			dev_warn(mmc_dev(host), "exceeding card's volts\n");
1664 	}
1665 
1666 	return ocr;
1667 }
1668 
__mmc_set_signal_voltage(struct mmc_host * host,int signal_voltage)1669 int __mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage)
1670 {
1671 	int err = 0;
1672 	int old_signal_voltage = host->ios.signal_voltage;
1673 
1674 	host->ios.signal_voltage = signal_voltage;
1675 	if (host->ops->start_signal_voltage_switch)
1676 		err = host->ops->start_signal_voltage_switch(host, &host->ios);
1677 
1678 	if (err)
1679 		host->ios.signal_voltage = old_signal_voltage;
1680 
1681 	return err;
1682 
1683 }
1684 
mmc_set_signal_voltage(struct mmc_host * host,int signal_voltage,u32 ocr)1685 int mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage, u32 ocr)
1686 {
1687 	struct mmc_command cmd = {0};
1688 	int err = 0;
1689 	u32 clock;
1690 
1691 	BUG_ON(!host);
1692 
1693 	/*
1694 	 * Send CMD11 only if the request is to switch the card to
1695 	 * 1.8V signalling.
1696 	 */
1697 	if (signal_voltage == MMC_SIGNAL_VOLTAGE_330)
1698 		return __mmc_set_signal_voltage(host, signal_voltage);
1699 
1700 	/*
1701 	 * If we cannot switch voltages, return failure so the caller
1702 	 * can continue without UHS mode
1703 	 */
1704 	if (!host->ops->start_signal_voltage_switch)
1705 		return -EPERM;
1706 	if (!host->ops->card_busy)
1707 		pr_warn("%s: cannot verify signal voltage switch\n",
1708 			mmc_hostname(host));
1709 
1710 	cmd.opcode = SD_SWITCH_VOLTAGE;
1711 	cmd.arg = 0;
1712 	cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
1713 
1714 	err = mmc_wait_for_cmd(host, &cmd, 0);
1715 	if (err)
1716 		return err;
1717 
1718 	if (!mmc_host_is_spi(host) && (cmd.resp[0] & R1_ERROR))
1719 		return -EIO;
1720 
1721 	/*
1722 	 * The card should drive cmd and dat[0:3] low immediately
1723 	 * after the response of cmd11, but wait 1 ms to be sure
1724 	 */
1725 	mmc_delay(1);
1726 	if (host->ops->card_busy && !host->ops->card_busy(host)) {
1727 		err = -EAGAIN;
1728 		goto power_cycle;
1729 	}
1730 	/*
1731 	 * During a signal voltage level switch, the clock must be gated
1732 	 * for 5 ms according to the SD spec
1733 	 */
1734 	clock = host->ios.clock;
1735 	host->ios.clock = 0;
1736 	mmc_set_ios(host);
1737 
1738 	if (__mmc_set_signal_voltage(host, signal_voltage)) {
1739 		/*
1740 		 * Voltages may not have been switched, but we've already
1741 		 * sent CMD11, so a power cycle is required anyway
1742 		 */
1743 		err = -EAGAIN;
1744 		goto power_cycle;
1745 	}
1746 
1747 	/* Keep clock gated for at least 10 ms, though spec only says 5 ms */
1748 	mmc_delay(10);
1749 	host->ios.clock = clock;
1750 	mmc_set_ios(host);
1751 
1752 	/* Wait for at least 1 ms according to spec */
1753 	mmc_delay(1);
1754 
1755 	/*
1756 	 * Failure to switch is indicated by the card holding
1757 	 * dat[0:3] low
1758 	 */
1759 	if (host->ops->card_busy && host->ops->card_busy(host))
1760 		err = -EAGAIN;
1761 
1762 power_cycle:
1763 	if (err) {
1764 		pr_debug("%s: Signal voltage switch failed, "
1765 			"power cycling card\n", mmc_hostname(host));
1766 		mmc_power_cycle(host, ocr);
1767 	}
1768 
1769 	return err;
1770 }
1771 
1772 /*
1773  * Select timing parameters for host.
1774  */
mmc_set_timing(struct mmc_host * host,unsigned int timing)1775 void mmc_set_timing(struct mmc_host *host, unsigned int timing)
1776 {
1777 	host->ios.timing = timing;
1778 	mmc_set_ios(host);
1779 }
1780 
1781 /*
1782  * Select appropriate driver type for host.
1783  */
mmc_set_driver_type(struct mmc_host * host,unsigned int drv_type)1784 void mmc_set_driver_type(struct mmc_host *host, unsigned int drv_type)
1785 {
1786 	host->ios.drv_type = drv_type;
1787 	mmc_set_ios(host);
1788 }
1789 
mmc_select_drive_strength(struct mmc_card * card,unsigned int max_dtr,int card_drv_type,int * drv_type)1790 int mmc_select_drive_strength(struct mmc_card *card, unsigned int max_dtr,
1791 			      int card_drv_type, int *drv_type)
1792 {
1793 	struct mmc_host *host = card->host;
1794 	int host_drv_type = SD_DRIVER_TYPE_B;
1795 
1796 	*drv_type = 0;
1797 
1798 	if (!host->ops->select_drive_strength)
1799 		return 0;
1800 
1801 	/* Use SD definition of driver strength for hosts */
1802 	if (host->caps & MMC_CAP_DRIVER_TYPE_A)
1803 		host_drv_type |= SD_DRIVER_TYPE_A;
1804 
1805 	if (host->caps & MMC_CAP_DRIVER_TYPE_C)
1806 		host_drv_type |= SD_DRIVER_TYPE_C;
1807 
1808 	if (host->caps & MMC_CAP_DRIVER_TYPE_D)
1809 		host_drv_type |= SD_DRIVER_TYPE_D;
1810 
1811 	/*
1812 	 * The drive strength that the hardware can support
1813 	 * depends on the board design.  Pass the appropriate
1814 	 * information and let the hardware specific code
1815 	 * return what is possible given the options
1816 	 */
1817 	return host->ops->select_drive_strength(card, max_dtr,
1818 						host_drv_type,
1819 						card_drv_type,
1820 						drv_type);
1821 }
1822 
1823 /*
1824  * Apply power to the MMC stack.  This is a two-stage process.
1825  * First, we enable power to the card without the clock running.
1826  * We then wait a bit for the power to stabilise.  Finally,
1827  * enable the bus drivers and clock to the card.
1828  *
1829  * We must _NOT_ enable the clock prior to power stablising.
1830  *
1831  * If a host does all the power sequencing itself, ignore the
1832  * initial MMC_POWER_UP stage.
1833  */
mmc_power_up(struct mmc_host * host,u32 ocr)1834 void mmc_power_up(struct mmc_host *host, u32 ocr)
1835 {
1836 	if (host->ios.power_mode == MMC_POWER_ON)
1837 		return;
1838 
1839 	mmc_pwrseq_pre_power_on(host);
1840 
1841 	host->ios.vdd = fls(ocr) - 1;
1842 	host->ios.power_mode = MMC_POWER_UP;
1843 	/* Set initial state and call mmc_set_ios */
1844 	mmc_set_initial_state(host);
1845 
1846 	/* Try to set signal voltage to 3.3V but fall back to 1.8v or 1.2v */
1847 	if (__mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330) == 0)
1848 		dev_dbg(mmc_dev(host), "Initial signal voltage of 3.3v\n");
1849 	else if (__mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180) == 0)
1850 		dev_dbg(mmc_dev(host), "Initial signal voltage of 1.8v\n");
1851 	else if (__mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120) == 0)
1852 		dev_dbg(mmc_dev(host), "Initial signal voltage of 1.2v\n");
1853 
1854 	/*
1855 	 * This delay should be sufficient to allow the power supply
1856 	 * to reach the minimum voltage.
1857 	 */
1858 	mmc_delay(10);
1859 
1860 	mmc_pwrseq_post_power_on(host);
1861 
1862 	host->ios.clock = host->f_init;
1863 
1864 	host->ios.power_mode = MMC_POWER_ON;
1865 	mmc_set_ios(host);
1866 
1867 	/*
1868 	 * This delay must be at least 74 clock sizes, or 1 ms, or the
1869 	 * time required to reach a stable voltage.
1870 	 */
1871 	mmc_delay(10);
1872 }
1873 
mmc_power_off(struct mmc_host * host)1874 void mmc_power_off(struct mmc_host *host)
1875 {
1876 	if (host->ios.power_mode == MMC_POWER_OFF)
1877 		return;
1878 
1879 	mmc_pwrseq_power_off(host);
1880 
1881 	host->ios.clock = 0;
1882 	host->ios.vdd = 0;
1883 
1884 	host->ios.power_mode = MMC_POWER_OFF;
1885 	/* Set initial state and call mmc_set_ios */
1886 	mmc_set_initial_state(host);
1887 
1888 	/*
1889 	 * Some configurations, such as the 802.11 SDIO card in the OLPC
1890 	 * XO-1.5, require a short delay after poweroff before the card
1891 	 * can be successfully turned on again.
1892 	 */
1893 	mmc_delay(1);
1894 }
1895 
mmc_power_cycle(struct mmc_host * host,u32 ocr)1896 void mmc_power_cycle(struct mmc_host *host, u32 ocr)
1897 {
1898 	mmc_power_off(host);
1899 	/* Wait at least 1 ms according to SD spec */
1900 	mmc_delay(1);
1901 	mmc_power_up(host, ocr);
1902 }
1903 
1904 /*
1905  * Cleanup when the last reference to the bus operator is dropped.
1906  */
__mmc_release_bus(struct mmc_host * host)1907 static void __mmc_release_bus(struct mmc_host *host)
1908 {
1909 	BUG_ON(!host);
1910 	BUG_ON(host->bus_refs);
1911 	BUG_ON(!host->bus_dead);
1912 
1913 	host->bus_ops = NULL;
1914 }
1915 
1916 /*
1917  * Increase reference count of bus operator
1918  */
mmc_bus_get(struct mmc_host * host)1919 static inline void mmc_bus_get(struct mmc_host *host)
1920 {
1921 	unsigned long flags;
1922 
1923 	spin_lock_irqsave(&host->lock, flags);
1924 	host->bus_refs++;
1925 	spin_unlock_irqrestore(&host->lock, flags);
1926 }
1927 
1928 /*
1929  * Decrease reference count of bus operator and free it if
1930  * it is the last reference.
1931  */
mmc_bus_put(struct mmc_host * host)1932 static inline void mmc_bus_put(struct mmc_host *host)
1933 {
1934 	unsigned long flags;
1935 
1936 	spin_lock_irqsave(&host->lock, flags);
1937 	host->bus_refs--;
1938 	if ((host->bus_refs == 0) && host->bus_ops)
1939 		__mmc_release_bus(host);
1940 	spin_unlock_irqrestore(&host->lock, flags);
1941 }
1942 
1943 /*
1944  * Assign a mmc bus handler to a host. Only one bus handler may control a
1945  * host at any given time.
1946  */
mmc_attach_bus(struct mmc_host * host,const struct mmc_bus_ops * ops)1947 void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops)
1948 {
1949 	unsigned long flags;
1950 
1951 	BUG_ON(!host);
1952 	BUG_ON(!ops);
1953 
1954 	WARN_ON(!host->claimed);
1955 
1956 	spin_lock_irqsave(&host->lock, flags);
1957 
1958 	BUG_ON(host->bus_ops);
1959 	BUG_ON(host->bus_refs);
1960 
1961 	host->bus_ops = ops;
1962 	host->bus_refs = 1;
1963 	host->bus_dead = 0;
1964 
1965 	spin_unlock_irqrestore(&host->lock, flags);
1966 }
1967 
1968 /*
1969  * Remove the current bus handler from a host.
1970  */
mmc_detach_bus(struct mmc_host * host)1971 void mmc_detach_bus(struct mmc_host *host)
1972 {
1973 	unsigned long flags;
1974 
1975 	BUG_ON(!host);
1976 
1977 	WARN_ON(!host->claimed);
1978 	WARN_ON(!host->bus_ops);
1979 
1980 	spin_lock_irqsave(&host->lock, flags);
1981 
1982 	host->bus_dead = 1;
1983 
1984 	spin_unlock_irqrestore(&host->lock, flags);
1985 
1986 	mmc_bus_put(host);
1987 }
1988 
_mmc_detect_change(struct mmc_host * host,unsigned long delay,bool cd_irq)1989 static void _mmc_detect_change(struct mmc_host *host, unsigned long delay,
1990 				bool cd_irq)
1991 {
1992 #ifdef CONFIG_MMC_DEBUG
1993 	unsigned long flags;
1994 	spin_lock_irqsave(&host->lock, flags);
1995 	WARN_ON(host->removed);
1996 	spin_unlock_irqrestore(&host->lock, flags);
1997 #endif
1998 
1999 	/*
2000 	 * If the device is configured as wakeup, we prevent a new sleep for
2001 	 * 5 s to give provision for user space to consume the event.
2002 	 */
2003 	if (cd_irq && !(host->caps & MMC_CAP_NEEDS_POLL) &&
2004 		device_can_wakeup(mmc_dev(host)))
2005 		pm_wakeup_event(mmc_dev(host), 5000);
2006 
2007 	host->detect_change = 1;
2008 	mmc_schedule_delayed_work(&host->detect, delay);
2009 }
2010 
2011 /**
2012  *	mmc_detect_change - process change of state on a MMC socket
2013  *	@host: host which changed state.
2014  *	@delay: optional delay to wait before detection (jiffies)
2015  *
2016  *	MMC drivers should call this when they detect a card has been
2017  *	inserted or removed. The MMC layer will confirm that any
2018  *	present card is still functional, and initialize any newly
2019  *	inserted.
2020  */
mmc_detect_change(struct mmc_host * host,unsigned long delay)2021 void mmc_detect_change(struct mmc_host *host, unsigned long delay)
2022 {
2023 	_mmc_detect_change(host, delay, true);
2024 }
2025 EXPORT_SYMBOL(mmc_detect_change);
2026 
mmc_init_erase(struct mmc_card * card)2027 void mmc_init_erase(struct mmc_card *card)
2028 {
2029 	unsigned int sz;
2030 
2031 	if (is_power_of_2(card->erase_size))
2032 		card->erase_shift = ffs(card->erase_size) - 1;
2033 	else
2034 		card->erase_shift = 0;
2035 
2036 	/*
2037 	 * It is possible to erase an arbitrarily large area of an SD or MMC
2038 	 * card.  That is not desirable because it can take a long time
2039 	 * (minutes) potentially delaying more important I/O, and also the
2040 	 * timeout calculations become increasingly hugely over-estimated.
2041 	 * Consequently, 'pref_erase' is defined as a guide to limit erases
2042 	 * to that size and alignment.
2043 	 *
2044 	 * For SD cards that define Allocation Unit size, limit erases to one
2045 	 * Allocation Unit at a time.
2046 	 * For MMC, have a stab at ai good value and for modern cards it will
2047 	 * end up being 4MiB. Note that if the value is too small, it can end
2048 	 * up taking longer to erase. Also note, erase_size is already set to
2049 	 * High Capacity Erase Size if available when this function is called.
2050 	 */
2051 	if (mmc_card_sd(card) && card->ssr.au) {
2052 		card->pref_erase = card->ssr.au;
2053 		card->erase_shift = ffs(card->ssr.au) - 1;
2054 	} else if (card->erase_size) {
2055 		sz = (card->csd.capacity << (card->csd.read_blkbits - 9)) >> 11;
2056 		if (sz < 128)
2057 			card->pref_erase = 512 * 1024 / 512;
2058 		else if (sz < 512)
2059 			card->pref_erase = 1024 * 1024 / 512;
2060 		else if (sz < 1024)
2061 			card->pref_erase = 2 * 1024 * 1024 / 512;
2062 		else
2063 			card->pref_erase = 4 * 1024 * 1024 / 512;
2064 		if (card->pref_erase < card->erase_size)
2065 			card->pref_erase = card->erase_size;
2066 		else {
2067 			sz = card->pref_erase % card->erase_size;
2068 			if (sz)
2069 				card->pref_erase += card->erase_size - sz;
2070 		}
2071 	} else
2072 		card->pref_erase = 0;
2073 }
2074 
mmc_mmc_erase_timeout(struct mmc_card * card,unsigned int arg,unsigned int qty)2075 static unsigned int mmc_mmc_erase_timeout(struct mmc_card *card,
2076 					  unsigned int arg, unsigned int qty)
2077 {
2078 	unsigned int erase_timeout;
2079 
2080 	if (arg == MMC_DISCARD_ARG ||
2081 	    (arg == MMC_TRIM_ARG && card->ext_csd.rev >= 6)) {
2082 		erase_timeout = card->ext_csd.trim_timeout;
2083 	} else if (card->ext_csd.erase_group_def & 1) {
2084 		/* High Capacity Erase Group Size uses HC timeouts */
2085 		if (arg == MMC_TRIM_ARG)
2086 			erase_timeout = card->ext_csd.trim_timeout;
2087 		else
2088 			erase_timeout = card->ext_csd.hc_erase_timeout;
2089 	} else {
2090 		/* CSD Erase Group Size uses write timeout */
2091 		unsigned int mult = (10 << card->csd.r2w_factor);
2092 		unsigned int timeout_clks = card->csd.tacc_clks * mult;
2093 		unsigned int timeout_us;
2094 
2095 		/* Avoid overflow: e.g. tacc_ns=80000000 mult=1280 */
2096 		if (card->csd.tacc_ns < 1000000)
2097 			timeout_us = (card->csd.tacc_ns * mult) / 1000;
2098 		else
2099 			timeout_us = (card->csd.tacc_ns / 1000) * mult;
2100 
2101 		/*
2102 		 * ios.clock is only a target.  The real clock rate might be
2103 		 * less but not that much less, so fudge it by multiplying by 2.
2104 		 */
2105 		timeout_clks <<= 1;
2106 		timeout_us += (timeout_clks * 1000) /
2107 			      (card->host->ios.clock / 1000);
2108 
2109 		erase_timeout = timeout_us / 1000;
2110 
2111 		/*
2112 		 * Theoretically, the calculation could underflow so round up
2113 		 * to 1ms in that case.
2114 		 */
2115 		if (!erase_timeout)
2116 			erase_timeout = 1;
2117 	}
2118 
2119 	/* Multiplier for secure operations */
2120 	if (arg & MMC_SECURE_ARGS) {
2121 		if (arg == MMC_SECURE_ERASE_ARG)
2122 			erase_timeout *= card->ext_csd.sec_erase_mult;
2123 		else
2124 			erase_timeout *= card->ext_csd.sec_trim_mult;
2125 	}
2126 
2127 	erase_timeout *= qty;
2128 
2129 	/*
2130 	 * Ensure at least a 1 second timeout for SPI as per
2131 	 * 'mmc_set_data_timeout()'
2132 	 */
2133 	if (mmc_host_is_spi(card->host) && erase_timeout < 1000)
2134 		erase_timeout = 1000;
2135 
2136 	return erase_timeout;
2137 }
2138 
mmc_sd_erase_timeout(struct mmc_card * card,unsigned int arg,unsigned int qty)2139 static unsigned int mmc_sd_erase_timeout(struct mmc_card *card,
2140 					 unsigned int arg,
2141 					 unsigned int qty)
2142 {
2143 	unsigned int erase_timeout;
2144 
2145 	if (card->ssr.erase_timeout) {
2146 		/* Erase timeout specified in SD Status Register (SSR) */
2147 		erase_timeout = card->ssr.erase_timeout * qty +
2148 				card->ssr.erase_offset;
2149 	} else {
2150 		/*
2151 		 * Erase timeout not specified in SD Status Register (SSR) so
2152 		 * use 250ms per write block.
2153 		 */
2154 		erase_timeout = 250 * qty;
2155 	}
2156 
2157 	/* Must not be less than 1 second */
2158 	if (erase_timeout < 1000)
2159 		erase_timeout = 1000;
2160 
2161 	return erase_timeout;
2162 }
2163 
mmc_erase_timeout(struct mmc_card * card,unsigned int arg,unsigned int qty)2164 static unsigned int mmc_erase_timeout(struct mmc_card *card,
2165 				      unsigned int arg,
2166 				      unsigned int qty)
2167 {
2168 	if (mmc_card_sd(card))
2169 		return mmc_sd_erase_timeout(card, arg, qty);
2170 	else
2171 		return mmc_mmc_erase_timeout(card, arg, qty);
2172 }
2173 
mmc_do_erase(struct mmc_card * card,unsigned int from,unsigned int to,unsigned int arg)2174 static int mmc_do_erase(struct mmc_card *card, unsigned int from,
2175 			unsigned int to, unsigned int arg)
2176 {
2177 	struct mmc_command cmd = {0};
2178 	unsigned int qty = 0, busy_timeout = 0;
2179 	bool use_r1b_resp = false;
2180 	unsigned long timeout;
2181 	int err;
2182 
2183 	mmc_retune_hold(card->host);
2184 
2185 	/*
2186 	 * qty is used to calculate the erase timeout which depends on how many
2187 	 * erase groups (or allocation units in SD terminology) are affected.
2188 	 * We count erasing part of an erase group as one erase group.
2189 	 * For SD, the allocation units are always a power of 2.  For MMC, the
2190 	 * erase group size is almost certainly also power of 2, but it does not
2191 	 * seem to insist on that in the JEDEC standard, so we fall back to
2192 	 * division in that case.  SD may not specify an allocation unit size,
2193 	 * in which case the timeout is based on the number of write blocks.
2194 	 *
2195 	 * Note that the timeout for secure trim 2 will only be correct if the
2196 	 * number of erase groups specified is the same as the total of all
2197 	 * preceding secure trim 1 commands.  Since the power may have been
2198 	 * lost since the secure trim 1 commands occurred, it is generally
2199 	 * impossible to calculate the secure trim 2 timeout correctly.
2200 	 */
2201 	if (card->erase_shift)
2202 		qty += ((to >> card->erase_shift) -
2203 			(from >> card->erase_shift)) + 1;
2204 	else if (mmc_card_sd(card))
2205 		qty += to - from + 1;
2206 	else
2207 		qty += ((to / card->erase_size) -
2208 			(from / card->erase_size)) + 1;
2209 
2210 	if (!mmc_card_blockaddr(card)) {
2211 		from <<= 9;
2212 		to <<= 9;
2213 	}
2214 
2215 	if (mmc_card_sd(card))
2216 		cmd.opcode = SD_ERASE_WR_BLK_START;
2217 	else
2218 		cmd.opcode = MMC_ERASE_GROUP_START;
2219 	cmd.arg = from;
2220 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
2221 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
2222 	if (err) {
2223 		pr_err("mmc_erase: group start error %d, "
2224 		       "status %#x\n", err, cmd.resp[0]);
2225 		err = -EIO;
2226 		goto out;
2227 	}
2228 
2229 	memset(&cmd, 0, sizeof(struct mmc_command));
2230 	if (mmc_card_sd(card))
2231 		cmd.opcode = SD_ERASE_WR_BLK_END;
2232 	else
2233 		cmd.opcode = MMC_ERASE_GROUP_END;
2234 	cmd.arg = to;
2235 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
2236 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
2237 	if (err) {
2238 		pr_err("mmc_erase: group end error %d, status %#x\n",
2239 		       err, cmd.resp[0]);
2240 		err = -EIO;
2241 		goto out;
2242 	}
2243 
2244 	memset(&cmd, 0, sizeof(struct mmc_command));
2245 	cmd.opcode = MMC_ERASE;
2246 	cmd.arg = arg;
2247 	busy_timeout = mmc_erase_timeout(card, arg, qty);
2248 	/*
2249 	 * If the host controller supports busy signalling and the timeout for
2250 	 * the erase operation does not exceed the max_busy_timeout, we should
2251 	 * use R1B response. Or we need to prevent the host from doing hw busy
2252 	 * detection, which is done by converting to a R1 response instead.
2253 	 */
2254 	if (card->host->max_busy_timeout &&
2255 	    busy_timeout > card->host->max_busy_timeout) {
2256 		cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
2257 	} else {
2258 		cmd.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
2259 		cmd.busy_timeout = busy_timeout;
2260 		use_r1b_resp = true;
2261 	}
2262 
2263 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
2264 	if (err) {
2265 		pr_err("mmc_erase: erase error %d, status %#x\n",
2266 		       err, cmd.resp[0]);
2267 		err = -EIO;
2268 		goto out;
2269 	}
2270 
2271 	if (mmc_host_is_spi(card->host))
2272 		goto out;
2273 
2274 	/*
2275 	 * In case of when R1B + MMC_CAP_WAIT_WHILE_BUSY is used, the polling
2276 	 * shall be avoided.
2277 	 */
2278 	if ((card->host->caps & MMC_CAP_WAIT_WHILE_BUSY) && use_r1b_resp)
2279 		goto out;
2280 
2281 	timeout = jiffies + msecs_to_jiffies(busy_timeout);
2282 	do {
2283 		memset(&cmd, 0, sizeof(struct mmc_command));
2284 		cmd.opcode = MMC_SEND_STATUS;
2285 		cmd.arg = card->rca << 16;
2286 		cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
2287 		/* Do not retry else we can't see errors */
2288 		err = mmc_wait_for_cmd(card->host, &cmd, 0);
2289 		if (err || (cmd.resp[0] & 0xFDF92000)) {
2290 			pr_err("error %d requesting status %#x\n",
2291 				err, cmd.resp[0]);
2292 			err = -EIO;
2293 			goto out;
2294 		}
2295 
2296 		/* Timeout if the device never becomes ready for data and
2297 		 * never leaves the program state.
2298 		 */
2299 		if (time_after(jiffies, timeout)) {
2300 			pr_err("%s: Card stuck in programming state! %s\n",
2301 				mmc_hostname(card->host), __func__);
2302 			err =  -EIO;
2303 			goto out;
2304 		}
2305 
2306 	} while (!(cmd.resp[0] & R1_READY_FOR_DATA) ||
2307 		 (R1_CURRENT_STATE(cmd.resp[0]) == R1_STATE_PRG));
2308 out:
2309 	mmc_retune_release(card->host);
2310 	return err;
2311 }
2312 
mmc_align_erase_size(struct mmc_card * card,unsigned int * from,unsigned int * to,unsigned int nr)2313 static unsigned int mmc_align_erase_size(struct mmc_card *card,
2314 					 unsigned int *from,
2315 					 unsigned int *to,
2316 					 unsigned int nr)
2317 {
2318 	unsigned int from_new = *from, nr_new = nr, rem;
2319 
2320 	/*
2321 	 * When the 'card->erase_size' is power of 2, we can use round_up/down()
2322 	 * to align the erase size efficiently.
2323 	 */
2324 	if (is_power_of_2(card->erase_size)) {
2325 		unsigned int temp = from_new;
2326 
2327 		from_new = round_up(temp, card->erase_size);
2328 		rem = from_new - temp;
2329 
2330 		if (nr_new > rem)
2331 			nr_new -= rem;
2332 		else
2333 			return 0;
2334 
2335 		nr_new = round_down(nr_new, card->erase_size);
2336 	} else {
2337 		rem = from_new % card->erase_size;
2338 		if (rem) {
2339 			rem = card->erase_size - rem;
2340 			from_new += rem;
2341 			if (nr_new > rem)
2342 				nr_new -= rem;
2343 			else
2344 				return 0;
2345 		}
2346 
2347 		rem = nr_new % card->erase_size;
2348 		if (rem)
2349 			nr_new -= rem;
2350 	}
2351 
2352 	if (nr_new == 0)
2353 		return 0;
2354 
2355 	*to = from_new + nr_new;
2356 	*from = from_new;
2357 
2358 	return nr_new;
2359 }
2360 
2361 /**
2362  * mmc_erase - erase sectors.
2363  * @card: card to erase
2364  * @from: first sector to erase
2365  * @nr: number of sectors to erase
2366  * @arg: erase command argument (SD supports only %MMC_ERASE_ARG)
2367  *
2368  * Caller must claim host before calling this function.
2369  */
mmc_erase(struct mmc_card * card,unsigned int from,unsigned int nr,unsigned int arg)2370 int mmc_erase(struct mmc_card *card, unsigned int from, unsigned int nr,
2371 	      unsigned int arg)
2372 {
2373 	unsigned int rem, to = from + nr;
2374 	int err;
2375 
2376 	if (!(card->host->caps & MMC_CAP_ERASE) ||
2377 	    !(card->csd.cmdclass & CCC_ERASE))
2378 		return -EOPNOTSUPP;
2379 
2380 	if (!card->erase_size)
2381 		return -EOPNOTSUPP;
2382 
2383 	if (mmc_card_sd(card) && arg != MMC_ERASE_ARG)
2384 		return -EOPNOTSUPP;
2385 
2386 	if ((arg & MMC_SECURE_ARGS) &&
2387 	    !(card->ext_csd.sec_feature_support & EXT_CSD_SEC_ER_EN))
2388 		return -EOPNOTSUPP;
2389 
2390 	if ((arg & MMC_TRIM_ARGS) &&
2391 	    !(card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN))
2392 		return -EOPNOTSUPP;
2393 
2394 	if (arg == MMC_SECURE_ERASE_ARG) {
2395 		if (from % card->erase_size || nr % card->erase_size)
2396 			return -EINVAL;
2397 	}
2398 
2399 	if (arg == MMC_ERASE_ARG)
2400 		nr = mmc_align_erase_size(card, &from, &to, nr);
2401 
2402 	if (nr == 0)
2403 		return 0;
2404 
2405 	if (to <= from)
2406 		return -EINVAL;
2407 
2408 	/* 'from' and 'to' are inclusive */
2409 	to -= 1;
2410 
2411 	/*
2412 	 * Special case where only one erase-group fits in the timeout budget:
2413 	 * If the region crosses an erase-group boundary on this particular
2414 	 * case, we will be trimming more than one erase-group which, does not
2415 	 * fit in the timeout budget of the controller, so we need to split it
2416 	 * and call mmc_do_erase() twice if necessary. This special case is
2417 	 * identified by the card->eg_boundary flag.
2418 	 */
2419 	rem = card->erase_size - (from % card->erase_size);
2420 	if ((arg & MMC_TRIM_ARGS) && (card->eg_boundary) && (nr > rem)) {
2421 		err = mmc_do_erase(card, from, from + rem - 1, arg);
2422 		from += rem;
2423 		if ((err) || (to <= from))
2424 			return err;
2425 	}
2426 
2427 	return mmc_do_erase(card, from, to, arg);
2428 }
2429 EXPORT_SYMBOL(mmc_erase);
2430 
mmc_can_erase(struct mmc_card * card)2431 int mmc_can_erase(struct mmc_card *card)
2432 {
2433 	if ((card->host->caps & MMC_CAP_ERASE) &&
2434 	    (card->csd.cmdclass & CCC_ERASE) && card->erase_size)
2435 		return 1;
2436 	return 0;
2437 }
2438 EXPORT_SYMBOL(mmc_can_erase);
2439 
mmc_can_trim(struct mmc_card * card)2440 int mmc_can_trim(struct mmc_card *card)
2441 {
2442 	if ((card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN) &&
2443 	    (!(card->quirks & MMC_QUIRK_TRIM_BROKEN)))
2444 		return 1;
2445 	return 0;
2446 }
2447 EXPORT_SYMBOL(mmc_can_trim);
2448 
mmc_can_discard(struct mmc_card * card)2449 int mmc_can_discard(struct mmc_card *card)
2450 {
2451 	/*
2452 	 * As there's no way to detect the discard support bit at v4.5
2453 	 * use the s/w feature support filed.
2454 	 */
2455 	if (card->ext_csd.feature_support & MMC_DISCARD_FEATURE)
2456 		return 1;
2457 	return 0;
2458 }
2459 EXPORT_SYMBOL(mmc_can_discard);
2460 
mmc_can_sanitize(struct mmc_card * card)2461 int mmc_can_sanitize(struct mmc_card *card)
2462 {
2463 	if (!mmc_can_trim(card) && !mmc_can_erase(card))
2464 		return 0;
2465 	if (card->ext_csd.sec_feature_support & EXT_CSD_SEC_SANITIZE)
2466 		return 1;
2467 	return 0;
2468 }
2469 EXPORT_SYMBOL(mmc_can_sanitize);
2470 
mmc_can_secure_erase_trim(struct mmc_card * card)2471 int mmc_can_secure_erase_trim(struct mmc_card *card)
2472 {
2473 	if ((card->ext_csd.sec_feature_support & EXT_CSD_SEC_ER_EN) &&
2474 	    !(card->quirks & MMC_QUIRK_SEC_ERASE_TRIM_BROKEN))
2475 		return 1;
2476 	return 0;
2477 }
2478 EXPORT_SYMBOL(mmc_can_secure_erase_trim);
2479 
mmc_erase_group_aligned(struct mmc_card * card,unsigned int from,unsigned int nr)2480 int mmc_erase_group_aligned(struct mmc_card *card, unsigned int from,
2481 			    unsigned int nr)
2482 {
2483 	if (!card->erase_size)
2484 		return 0;
2485 	if (from % card->erase_size || nr % card->erase_size)
2486 		return 0;
2487 	return 1;
2488 }
2489 EXPORT_SYMBOL(mmc_erase_group_aligned);
2490 
mmc_do_calc_max_discard(struct mmc_card * card,unsigned int arg)2491 static unsigned int mmc_do_calc_max_discard(struct mmc_card *card,
2492 					    unsigned int arg)
2493 {
2494 	struct mmc_host *host = card->host;
2495 	unsigned int max_discard, x, y, qty = 0, max_qty, min_qty, timeout;
2496 	unsigned int last_timeout = 0;
2497 	unsigned int max_busy_timeout = host->max_busy_timeout ?
2498 			host->max_busy_timeout : MMC_ERASE_TIMEOUT_MS;
2499 
2500 	if (card->erase_shift) {
2501 		max_qty = UINT_MAX >> card->erase_shift;
2502 		min_qty = card->pref_erase >> card->erase_shift;
2503 	} else if (mmc_card_sd(card)) {
2504 		max_qty = UINT_MAX;
2505 		min_qty = card->pref_erase;
2506 	} else {
2507 		max_qty = UINT_MAX / card->erase_size;
2508 		min_qty = card->pref_erase / card->erase_size;
2509 	}
2510 
2511 	/*
2512 	 * We should not only use 'host->max_busy_timeout' as the limitation
2513 	 * when deciding the max discard sectors. We should set a balance value
2514 	 * to improve the erase speed, and it can not get too long timeout at
2515 	 * the same time.
2516 	 *
2517 	 * Here we set 'card->pref_erase' as the minimal discard sectors no
2518 	 * matter what size of 'host->max_busy_timeout', but if the
2519 	 * 'host->max_busy_timeout' is large enough for more discard sectors,
2520 	 * then we can continue to increase the max discard sectors until we
2521 	 * get a balance value. In cases when the 'host->max_busy_timeout'
2522 	 * isn't specified, use the default max erase timeout.
2523 	 */
2524 	do {
2525 		y = 0;
2526 		for (x = 1; x && x <= max_qty && max_qty - x >= qty; x <<= 1) {
2527 			timeout = mmc_erase_timeout(card, arg, qty + x);
2528 
2529 			if (qty + x > min_qty && timeout > max_busy_timeout)
2530 				break;
2531 
2532 			if (timeout < last_timeout)
2533 				break;
2534 			last_timeout = timeout;
2535 			y = x;
2536 		}
2537 		qty += y;
2538 	} while (y);
2539 
2540 	if (!qty)
2541 		return 0;
2542 
2543 	/*
2544 	 * When specifying a sector range to trim, chances are we might cross
2545 	 * an erase-group boundary even if the amount of sectors is less than
2546 	 * one erase-group.
2547 	 * If we can only fit one erase-group in the controller timeout budget,
2548 	 * we have to care that erase-group boundaries are not crossed by a
2549 	 * single trim operation. We flag that special case with "eg_boundary".
2550 	 * In all other cases we can just decrement qty and pretend that we
2551 	 * always touch (qty + 1) erase-groups as a simple optimization.
2552 	 */
2553 	if (qty == 1)
2554 		card->eg_boundary = 1;
2555 	else
2556 		qty--;
2557 
2558 	/* Convert qty to sectors */
2559 	if (card->erase_shift)
2560 		max_discard = qty << card->erase_shift;
2561 	else if (mmc_card_sd(card))
2562 		max_discard = qty + 1;
2563 	else
2564 		max_discard = qty * card->erase_size;
2565 
2566 	return max_discard;
2567 }
2568 
mmc_calc_max_discard(struct mmc_card * card)2569 unsigned int mmc_calc_max_discard(struct mmc_card *card)
2570 {
2571 	struct mmc_host *host = card->host;
2572 	unsigned int max_discard, max_trim;
2573 
2574 	/*
2575 	 * Without erase_group_def set, MMC erase timeout depends on clock
2576 	 * frequence which can change.  In that case, the best choice is
2577 	 * just the preferred erase size.
2578 	 */
2579 	if (mmc_card_mmc(card) && !(card->ext_csd.erase_group_def & 1))
2580 		return card->pref_erase;
2581 
2582 	max_discard = mmc_do_calc_max_discard(card, MMC_ERASE_ARG);
2583 	if (mmc_can_trim(card)) {
2584 		max_trim = mmc_do_calc_max_discard(card, MMC_TRIM_ARG);
2585 		if (max_trim < max_discard)
2586 			max_discard = max_trim;
2587 	} else if (max_discard < card->erase_size) {
2588 		max_discard = 0;
2589 	}
2590 	pr_debug("%s: calculated max. discard sectors %u for timeout %u ms\n",
2591 		mmc_hostname(host), max_discard, host->max_busy_timeout ?
2592 		host->max_busy_timeout : MMC_ERASE_TIMEOUT_MS);
2593 	return max_discard;
2594 }
2595 EXPORT_SYMBOL(mmc_calc_max_discard);
2596 
mmc_set_blocklen(struct mmc_card * card,unsigned int blocklen)2597 int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen)
2598 {
2599 	struct mmc_command cmd = {0};
2600 
2601 	if (mmc_card_blockaddr(card) || mmc_card_ddr52(card) ||
2602 	    mmc_card_hs400(card) || mmc_card_hs400es(card))
2603 		return 0;
2604 
2605 	cmd.opcode = MMC_SET_BLOCKLEN;
2606 	cmd.arg = blocklen;
2607 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
2608 	return mmc_wait_for_cmd(card->host, &cmd, 5);
2609 }
2610 EXPORT_SYMBOL(mmc_set_blocklen);
2611 
mmc_set_blockcount(struct mmc_card * card,unsigned int blockcount,bool is_rel_write)2612 int mmc_set_blockcount(struct mmc_card *card, unsigned int blockcount,
2613 			bool is_rel_write)
2614 {
2615 	struct mmc_command cmd = {0};
2616 
2617 	cmd.opcode = MMC_SET_BLOCK_COUNT;
2618 	cmd.arg = blockcount & 0x0000FFFF;
2619 	if (is_rel_write)
2620 		cmd.arg |= 1 << 31;
2621 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
2622 	return mmc_wait_for_cmd(card->host, &cmd, 5);
2623 }
2624 EXPORT_SYMBOL(mmc_set_blockcount);
2625 
mmc_hw_reset_for_init(struct mmc_host * host)2626 static void mmc_hw_reset_for_init(struct mmc_host *host)
2627 {
2628 	if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
2629 		return;
2630 	host->ops->hw_reset(host);
2631 }
2632 
mmc_hw_reset(struct mmc_host * host)2633 int mmc_hw_reset(struct mmc_host *host)
2634 {
2635 	int ret;
2636 
2637 	if (!host->card)
2638 		return -EINVAL;
2639 
2640 	mmc_bus_get(host);
2641 	if (!host->bus_ops || host->bus_dead || !host->bus_ops->reset) {
2642 		mmc_bus_put(host);
2643 		return -EOPNOTSUPP;
2644 	}
2645 
2646 	ret = host->bus_ops->reset(host);
2647 	mmc_bus_put(host);
2648 
2649 	if (ret)
2650 		pr_warn("%s: tried to reset card, got error %d\n",
2651 			mmc_hostname(host), ret);
2652 
2653 	return ret;
2654 }
2655 EXPORT_SYMBOL(mmc_hw_reset);
2656 
mmc_rescan_try_freq(struct mmc_host * host,unsigned freq)2657 static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
2658 {
2659 	host->f_init = freq;
2660 
2661 #ifdef CONFIG_MMC_DEBUG
2662 	pr_info("%s: %s: trying to init card at %u Hz\n",
2663 		mmc_hostname(host), __func__, host->f_init);
2664 #endif
2665 	mmc_power_up(host, host->ocr_avail);
2666 
2667 	/*
2668 	 * Some eMMCs (with VCCQ always on) may not be reset after power up, so
2669 	 * do a hardware reset if possible.
2670 	 */
2671 	mmc_hw_reset_for_init(host);
2672 
2673 	/*
2674 	 * sdio_reset sends CMD52 to reset card.  Since we do not know
2675 	 * if the card is being re-initialized, just send it.  CMD52
2676 	 * should be ignored by SD/eMMC cards.
2677 	 * Skip it if we already know that we do not support SDIO commands
2678 	 */
2679 	if (!(host->caps2 & MMC_CAP2_NO_SDIO))
2680 		sdio_reset(host);
2681 
2682 	mmc_go_idle(host);
2683 
2684 	if (!(host->caps2 & MMC_CAP2_NO_SD))
2685 		mmc_send_if_cond(host, host->ocr_avail);
2686 
2687 	/* Order's important: probe SDIO, then SD, then MMC */
2688 	if (!(host->caps2 & MMC_CAP2_NO_SDIO))
2689 		if (!mmc_attach_sdio(host))
2690 			return 0;
2691 
2692 	if (!(host->caps2 & MMC_CAP2_NO_SD))
2693 		if (!mmc_attach_sd(host))
2694 			return 0;
2695 
2696 	if (!(host->caps2 & MMC_CAP2_NO_MMC))
2697 		if (!mmc_attach_mmc(host))
2698 			return 0;
2699 
2700 	mmc_power_off(host);
2701 	return -EIO;
2702 }
2703 
_mmc_detect_card_removed(struct mmc_host * host)2704 int _mmc_detect_card_removed(struct mmc_host *host)
2705 {
2706 	int ret;
2707 
2708 	if (!host->card || mmc_card_removed(host->card))
2709 		return 1;
2710 
2711 	ret = host->bus_ops->alive(host);
2712 
2713 	/*
2714 	 * Card detect status and alive check may be out of sync if card is
2715 	 * removed slowly, when card detect switch changes while card/slot
2716 	 * pads are still contacted in hardware (refer to "SD Card Mechanical
2717 	 * Addendum, Appendix C: Card Detection Switch"). So reschedule a
2718 	 * detect work 200ms later for this case.
2719 	 */
2720 	if (!ret && host->ops->get_cd && !host->ops->get_cd(host)) {
2721 		mmc_detect_change(host, msecs_to_jiffies(200));
2722 		pr_debug("%s: card removed too slowly\n", mmc_hostname(host));
2723 	}
2724 
2725 	if (ret) {
2726 		mmc_card_set_removed(host->card);
2727 		pr_debug("%s: card remove detected\n", mmc_hostname(host));
2728 	}
2729 
2730 	return ret;
2731 }
2732 
mmc_detect_card_removed(struct mmc_host * host)2733 int mmc_detect_card_removed(struct mmc_host *host)
2734 {
2735 	struct mmc_card *card = host->card;
2736 	int ret;
2737 
2738 	WARN_ON(!host->claimed);
2739 
2740 	if (!card)
2741 		return 1;
2742 
2743 	if (!mmc_card_is_removable(host))
2744 		return 0;
2745 
2746 	ret = mmc_card_removed(card);
2747 	/*
2748 	 * The card will be considered unchanged unless we have been asked to
2749 	 * detect a change or host requires polling to provide card detection.
2750 	 */
2751 	if (!host->detect_change && !(host->caps & MMC_CAP_NEEDS_POLL))
2752 		return ret;
2753 
2754 	host->detect_change = 0;
2755 	if (!ret) {
2756 		ret = _mmc_detect_card_removed(host);
2757 		if (ret && (host->caps & MMC_CAP_NEEDS_POLL)) {
2758 			/*
2759 			 * Schedule a detect work as soon as possible to let a
2760 			 * rescan handle the card removal.
2761 			 */
2762 			cancel_delayed_work(&host->detect);
2763 			_mmc_detect_change(host, 0, false);
2764 		}
2765 	}
2766 
2767 	return ret;
2768 }
2769 EXPORT_SYMBOL(mmc_detect_card_removed);
2770 
mmc_rescan(struct work_struct * work)2771 void mmc_rescan(struct work_struct *work)
2772 {
2773 	struct mmc_host *host =
2774 		container_of(work, struct mmc_host, detect.work);
2775 	int i;
2776 
2777 	if (host->rescan_disable)
2778 		return;
2779 
2780 	/* If there is a non-removable card registered, only scan once */
2781 	if (!mmc_card_is_removable(host) && host->rescan_entered)
2782 		return;
2783 	host->rescan_entered = 1;
2784 
2785 	if (host->trigger_card_event && host->ops->card_event) {
2786 		mmc_claim_host(host);
2787 		host->ops->card_event(host);
2788 		mmc_release_host(host);
2789 		host->trigger_card_event = false;
2790 	}
2791 
2792 	mmc_bus_get(host);
2793 
2794 	/*
2795 	 * if there is a _removable_ card registered, check whether it is
2796 	 * still present
2797 	 */
2798 	if (host->bus_ops && !host->bus_dead && mmc_card_is_removable(host))
2799 		host->bus_ops->detect(host);
2800 
2801 	host->detect_change = 0;
2802 
2803 	/*
2804 	 * Let mmc_bus_put() free the bus/bus_ops if we've found that
2805 	 * the card is no longer present.
2806 	 */
2807 	mmc_bus_put(host);
2808 	mmc_bus_get(host);
2809 
2810 	/* if there still is a card present, stop here */
2811 	if (host->bus_ops != NULL) {
2812 		mmc_bus_put(host);
2813 		goto out;
2814 	}
2815 
2816 	/*
2817 	 * Only we can add a new handler, so it's safe to
2818 	 * release the lock here.
2819 	 */
2820 	mmc_bus_put(host);
2821 
2822 	mmc_claim_host(host);
2823 	if (mmc_card_is_removable(host) && host->ops->get_cd &&
2824 			host->ops->get_cd(host) == 0) {
2825 		mmc_power_off(host);
2826 		mmc_release_host(host);
2827 		goto out;
2828 	}
2829 
2830 	for (i = 0; i < ARRAY_SIZE(freqs); i++) {
2831 		if (!mmc_rescan_try_freq(host, max(freqs[i], host->f_min)))
2832 			break;
2833 		if (freqs[i] <= host->f_min)
2834 			break;
2835 	}
2836 	mmc_release_host(host);
2837 
2838  out:
2839 	if (host->caps & MMC_CAP_NEEDS_POLL)
2840 		mmc_schedule_delayed_work(&host->detect, HZ);
2841 }
2842 
mmc_start_host(struct mmc_host * host)2843 void mmc_start_host(struct mmc_host *host)
2844 {
2845 	host->f_init = max(freqs[0], host->f_min);
2846 	host->rescan_disable = 0;
2847 	host->ios.power_mode = MMC_POWER_UNDEFINED;
2848 
2849 	mmc_claim_host(host);
2850 	if (host->caps2 & MMC_CAP2_NO_PRESCAN_POWERUP)
2851 		mmc_power_off(host);
2852 	else
2853 		mmc_power_up(host, host->ocr_avail);
2854 	mmc_release_host(host);
2855 
2856 	mmc_gpiod_request_cd_irq(host);
2857 	_mmc_detect_change(host, 0, false);
2858 }
2859 
mmc_stop_host(struct mmc_host * host)2860 void mmc_stop_host(struct mmc_host *host)
2861 {
2862 #ifdef CONFIG_MMC_DEBUG
2863 	unsigned long flags;
2864 	spin_lock_irqsave(&host->lock, flags);
2865 	host->removed = 1;
2866 	spin_unlock_irqrestore(&host->lock, flags);
2867 #endif
2868 	if (host->slot.cd_irq >= 0)
2869 		disable_irq(host->slot.cd_irq);
2870 
2871 	host->rescan_disable = 1;
2872 	cancel_delayed_work_sync(&host->detect);
2873 
2874 	/* clear pm flags now and let card drivers set them as needed */
2875 	host->pm_flags = 0;
2876 
2877 	mmc_bus_get(host);
2878 	if (host->bus_ops && !host->bus_dead) {
2879 		/* Calling bus_ops->remove() with a claimed host can deadlock */
2880 		host->bus_ops->remove(host);
2881 		mmc_claim_host(host);
2882 		mmc_detach_bus(host);
2883 		mmc_power_off(host);
2884 		mmc_release_host(host);
2885 		mmc_bus_put(host);
2886 		return;
2887 	}
2888 	mmc_bus_put(host);
2889 
2890 	BUG_ON(host->card);
2891 
2892 	mmc_claim_host(host);
2893 	mmc_power_off(host);
2894 	mmc_release_host(host);
2895 }
2896 
mmc_power_save_host(struct mmc_host * host)2897 int mmc_power_save_host(struct mmc_host *host)
2898 {
2899 	int ret = 0;
2900 
2901 #ifdef CONFIG_MMC_DEBUG
2902 	pr_info("%s: %s: powering down\n", mmc_hostname(host), __func__);
2903 #endif
2904 
2905 	mmc_bus_get(host);
2906 
2907 	if (!host->bus_ops || host->bus_dead) {
2908 		mmc_bus_put(host);
2909 		return -EINVAL;
2910 	}
2911 
2912 	if (host->bus_ops->power_save)
2913 		ret = host->bus_ops->power_save(host);
2914 
2915 	mmc_bus_put(host);
2916 
2917 	mmc_power_off(host);
2918 
2919 	return ret;
2920 }
2921 EXPORT_SYMBOL(mmc_power_save_host);
2922 
mmc_power_restore_host(struct mmc_host * host)2923 int mmc_power_restore_host(struct mmc_host *host)
2924 {
2925 	int ret;
2926 
2927 #ifdef CONFIG_MMC_DEBUG
2928 	pr_info("%s: %s: powering up\n", mmc_hostname(host), __func__);
2929 #endif
2930 
2931 	mmc_bus_get(host);
2932 
2933 	if (!host->bus_ops || host->bus_dead) {
2934 		mmc_bus_put(host);
2935 		return -EINVAL;
2936 	}
2937 
2938 	mmc_power_up(host, host->card->ocr);
2939 	ret = host->bus_ops->power_restore(host);
2940 
2941 	mmc_bus_put(host);
2942 
2943 	return ret;
2944 }
2945 EXPORT_SYMBOL(mmc_power_restore_host);
2946 
2947 /*
2948  * Flush the cache to the non-volatile storage.
2949  */
mmc_flush_cache(struct mmc_card * card)2950 int mmc_flush_cache(struct mmc_card *card)
2951 {
2952 	int err = 0;
2953 
2954 	if (mmc_card_mmc(card) &&
2955 			(card->ext_csd.cache_size > 0) &&
2956 			(card->ext_csd.cache_ctrl & 1)) {
2957 		err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
2958 				EXT_CSD_FLUSH_CACHE, 1, 0);
2959 		if (err)
2960 			pr_err("%s: cache flush error %d\n",
2961 					mmc_hostname(card->host), err);
2962 	}
2963 
2964 	return err;
2965 }
2966 EXPORT_SYMBOL(mmc_flush_cache);
2967 
2968 #ifdef CONFIG_PM_SLEEP
2969 /* Do the card removal on suspend if card is assumed removeable
2970  * Do that in pm notifier while userspace isn't yet frozen, so we will be able
2971    to sync the card.
2972 */
mmc_pm_notify(struct notifier_block * notify_block,unsigned long mode,void * unused)2973 static int mmc_pm_notify(struct notifier_block *notify_block,
2974 			unsigned long mode, void *unused)
2975 {
2976 	struct mmc_host *host = container_of(
2977 		notify_block, struct mmc_host, pm_notify);
2978 	unsigned long flags;
2979 	int err = 0;
2980 
2981 	switch (mode) {
2982 	case PM_HIBERNATION_PREPARE:
2983 	case PM_SUSPEND_PREPARE:
2984 	case PM_RESTORE_PREPARE:
2985 		spin_lock_irqsave(&host->lock, flags);
2986 		host->rescan_disable = 1;
2987 		spin_unlock_irqrestore(&host->lock, flags);
2988 		cancel_delayed_work_sync(&host->detect);
2989 
2990 		if (!host->bus_ops)
2991 			break;
2992 
2993 		/* Validate prerequisites for suspend */
2994 		if (host->bus_ops->pre_suspend)
2995 			err = host->bus_ops->pre_suspend(host);
2996 		if (!err)
2997 			break;
2998 
2999 		if (!mmc_card_is_removable(host)) {
3000 			dev_warn(mmc_dev(host),
3001 				 "pre_suspend failed for non-removable host: "
3002 				 "%d\n", err);
3003 			/* Avoid removing non-removable hosts */
3004 			break;
3005 		}
3006 
3007 		/* Calling bus_ops->remove() with a claimed host can deadlock */
3008 		host->bus_ops->remove(host);
3009 		mmc_claim_host(host);
3010 		mmc_detach_bus(host);
3011 		mmc_power_off(host);
3012 		mmc_release_host(host);
3013 		host->pm_flags = 0;
3014 		break;
3015 
3016 	case PM_POST_SUSPEND:
3017 	case PM_POST_HIBERNATION:
3018 	case PM_POST_RESTORE:
3019 
3020 		spin_lock_irqsave(&host->lock, flags);
3021 		host->rescan_disable = 0;
3022 		spin_unlock_irqrestore(&host->lock, flags);
3023 		_mmc_detect_change(host, 0, false);
3024 
3025 	}
3026 
3027 	return 0;
3028 }
3029 
mmc_register_pm_notifier(struct mmc_host * host)3030 void mmc_register_pm_notifier(struct mmc_host *host)
3031 {
3032 	host->pm_notify.notifier_call = mmc_pm_notify;
3033 	register_pm_notifier(&host->pm_notify);
3034 }
3035 
mmc_unregister_pm_notifier(struct mmc_host * host)3036 void mmc_unregister_pm_notifier(struct mmc_host *host)
3037 {
3038 	unregister_pm_notifier(&host->pm_notify);
3039 }
3040 #endif
3041 
3042 /**
3043  * mmc_init_context_info() - init synchronization context
3044  * @host: mmc host
3045  *
3046  * Init struct context_info needed to implement asynchronous
3047  * request mechanism, used by mmc core, host driver and mmc requests
3048  * supplier.
3049  */
mmc_init_context_info(struct mmc_host * host)3050 void mmc_init_context_info(struct mmc_host *host)
3051 {
3052 	spin_lock_init(&host->context_info.lock);
3053 	host->context_info.is_new_req = false;
3054 	host->context_info.is_done_rcv = false;
3055 	host->context_info.is_waiting_last_req = false;
3056 	init_waitqueue_head(&host->context_info.wait);
3057 }
3058 
3059 #ifdef CONFIG_MMC_EMBEDDED_SDIO
mmc_set_embedded_sdio_data(struct mmc_host * host,struct sdio_cis * cis,struct sdio_cccr * cccr,struct sdio_embedded_func * funcs,int num_funcs)3060 void mmc_set_embedded_sdio_data(struct mmc_host *host,
3061 				struct sdio_cis *cis,
3062 				struct sdio_cccr *cccr,
3063 				struct sdio_embedded_func *funcs,
3064 				int num_funcs)
3065 {
3066 	host->embedded_sdio_data.cis = cis;
3067 	host->embedded_sdio_data.cccr = cccr;
3068 	host->embedded_sdio_data.funcs = funcs;
3069 	host->embedded_sdio_data.num_funcs = num_funcs;
3070 }
3071 
3072 EXPORT_SYMBOL(mmc_set_embedded_sdio_data);
3073 #endif
3074 
mmc_init(void)3075 static int __init mmc_init(void)
3076 {
3077 	int ret;
3078 
3079 	ret = mmc_register_bus();
3080 	if (ret)
3081 		return ret;
3082 
3083 	ret = mmc_register_host_class();
3084 	if (ret)
3085 		goto unregister_bus;
3086 
3087 	ret = sdio_register_bus();
3088 	if (ret)
3089 		goto unregister_host_class;
3090 
3091 	return 0;
3092 
3093 unregister_host_class:
3094 	mmc_unregister_host_class();
3095 unregister_bus:
3096 	mmc_unregister_bus();
3097 	return ret;
3098 }
3099 
mmc_exit(void)3100 static void __exit mmc_exit(void)
3101 {
3102 	sdio_unregister_bus();
3103 	mmc_unregister_host_class();
3104 	mmc_unregister_bus();
3105 }
3106 
3107 #ifdef CONFIG_BLOCK
3108 static ssize_t
latency_hist_show(struct device * dev,struct device_attribute * attr,char * buf)3109 latency_hist_show(struct device *dev, struct device_attribute *attr, char *buf)
3110 {
3111 	struct mmc_host *host = cls_dev_to_mmc_host(dev);
3112 	size_t written_bytes;
3113 
3114 	written_bytes = blk_latency_hist_show("Read", &host->io_lat_read,
3115 			buf, PAGE_SIZE);
3116 	written_bytes += blk_latency_hist_show("Write", &host->io_lat_write,
3117 			buf + written_bytes, PAGE_SIZE - written_bytes);
3118 
3119 	return written_bytes;
3120 }
3121 
3122 /*
3123  * Values permitted 0, 1, 2.
3124  * 0 -> Disable IO latency histograms (default)
3125  * 1 -> Enable IO latency histograms
3126  * 2 -> Zero out IO latency histograms
3127  */
3128 static ssize_t
latency_hist_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)3129 latency_hist_store(struct device *dev, struct device_attribute *attr,
3130 		   const char *buf, size_t count)
3131 {
3132 	struct mmc_host *host = cls_dev_to_mmc_host(dev);
3133 	long value;
3134 
3135 	if (kstrtol(buf, 0, &value))
3136 		return -EINVAL;
3137 	if (value == BLK_IO_LAT_HIST_ZERO) {
3138 		memset(&host->io_lat_read, 0, sizeof(host->io_lat_read));
3139 		memset(&host->io_lat_write, 0, sizeof(host->io_lat_write));
3140 	} else if (value == BLK_IO_LAT_HIST_ENABLE ||
3141 		 value == BLK_IO_LAT_HIST_DISABLE)
3142 		host->latency_hist_enabled = value;
3143 	return count;
3144 }
3145 
3146 static DEVICE_ATTR(latency_hist, S_IRUGO | S_IWUSR,
3147 		   latency_hist_show, latency_hist_store);
3148 
3149 void
mmc_latency_hist_sysfs_init(struct mmc_host * host)3150 mmc_latency_hist_sysfs_init(struct mmc_host *host)
3151 {
3152 	if (device_create_file(&host->class_dev, &dev_attr_latency_hist))
3153 		dev_err(&host->class_dev,
3154 			"Failed to create latency_hist sysfs entry\n");
3155 }
3156 
3157 void
mmc_latency_hist_sysfs_exit(struct mmc_host * host)3158 mmc_latency_hist_sysfs_exit(struct mmc_host *host)
3159 {
3160 	device_remove_file(&host->class_dev, &dev_attr_latency_hist);
3161 }
3162 #endif
3163 
3164 subsys_initcall(mmc_init);
3165 module_exit(mmc_exit);
3166 
3167 MODULE_LICENSE("GPL");
3168