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-rw-r--r--drivers/mmc/mmc.c914
1 files changed, 914 insertions, 0 deletions
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
new file mode 100644
index 000000000000..e40026328251
--- /dev/null
+++ b/drivers/mmc/mmc.c
@@ -0,0 +1,914 @@
1/*
2 * linux/drivers/mmc/mmc.c
3 *
4 * Copyright (C) 2003-2004 Russell King, All Rights Reserved.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10#include <linux/config.h>
11#include <linux/module.h>
12#include <linux/init.h>
13#include <linux/interrupt.h>
14#include <linux/completion.h>
15#include <linux/device.h>
16#include <linux/delay.h>
17#include <linux/pagemap.h>
18#include <linux/err.h>
19
20#include <linux/mmc/card.h>
21#include <linux/mmc/host.h>
22#include <linux/mmc/protocol.h>
23
24#include "mmc.h"
25
26#ifdef CONFIG_MMC_DEBUG
27#define DBG(x...) printk(KERN_DEBUG x)
28#else
29#define DBG(x...) do { } while (0)
30#endif
31
32#define CMD_RETRIES 3
33
34/*
35 * OCR Bit positions to 10s of Vdd mV.
36 */
37static const unsigned short mmc_ocr_bit_to_vdd[] = {
38 150, 155, 160, 165, 170, 180, 190, 200,
39 210, 220, 230, 240, 250, 260, 270, 280,
40 290, 300, 310, 320, 330, 340, 350, 360
41};
42
43static const unsigned int tran_exp[] = {
44 10000, 100000, 1000000, 10000000,
45 0, 0, 0, 0
46};
47
48static const unsigned char tran_mant[] = {
49 0, 10, 12, 13, 15, 20, 25, 30,
50 35, 40, 45, 50, 55, 60, 70, 80,
51};
52
53static const unsigned int tacc_exp[] = {
54 1, 10, 100, 1000, 10000, 100000, 1000000, 10000000,
55};
56
57static const unsigned int tacc_mant[] = {
58 0, 10, 12, 13, 15, 20, 25, 30,
59 35, 40, 45, 50, 55, 60, 70, 80,
60};
61
62
63/**
64 * mmc_request_done - finish processing an MMC command
65 * @host: MMC host which completed command
66 * @mrq: MMC request which completed
67 *
68 * MMC drivers should call this function when they have completed
69 * their processing of a command. This should be called before the
70 * data part of the command has completed.
71 */
72void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
73{
74 struct mmc_command *cmd = mrq->cmd;
75 int err = mrq->cmd->error;
76 DBG("MMC: req done (%02x): %d: %08x %08x %08x %08x\n", cmd->opcode,
77 err, cmd->resp[0], cmd->resp[1], cmd->resp[2], cmd->resp[3]);
78
79 if (err && cmd->retries) {
80 cmd->retries--;
81 cmd->error = 0;
82 host->ops->request(host, mrq);
83 } else if (mrq->done) {
84 mrq->done(mrq);
85 }
86}
87
88EXPORT_SYMBOL(mmc_request_done);
89
90/**
91 * mmc_start_request - start a command on a host
92 * @host: MMC host to start command on
93 * @mrq: MMC request to start
94 *
95 * Queue a command on the specified host. We expect the
96 * caller to be holding the host lock with interrupts disabled.
97 */
98void
99mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
100{
101 DBG("MMC: starting cmd %02x arg %08x flags %08x\n",
102 mrq->cmd->opcode, mrq->cmd->arg, mrq->cmd->flags);
103
104 WARN_ON(host->card_busy == NULL);
105
106 mrq->cmd->error = 0;
107 mrq->cmd->mrq = mrq;
108 if (mrq->data) {
109 mrq->cmd->data = mrq->data;
110 mrq->data->error = 0;
111 mrq->data->mrq = mrq;
112 if (mrq->stop) {
113 mrq->data->stop = mrq->stop;
114 mrq->stop->error = 0;
115 mrq->stop->mrq = mrq;
116 }
117 }
118 host->ops->request(host, mrq);
119}
120
121EXPORT_SYMBOL(mmc_start_request);
122
123static void mmc_wait_done(struct mmc_request *mrq)
124{
125 complete(mrq->done_data);
126}
127
128int mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq)
129{
130 DECLARE_COMPLETION(complete);
131
132 mrq->done_data = &complete;
133 mrq->done = mmc_wait_done;
134
135 mmc_start_request(host, mrq);
136
137 wait_for_completion(&complete);
138
139 return 0;
140}
141
142EXPORT_SYMBOL(mmc_wait_for_req);
143
144/**
145 * mmc_wait_for_cmd - start a command and wait for completion
146 * @host: MMC host to start command
147 * @cmd: MMC command to start
148 * @retries: maximum number of retries
149 *
150 * Start a new MMC command for a host, and wait for the command
151 * to complete. Return any error that occurred while the command
152 * was executing. Do not attempt to parse the response.
153 */
154int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries)
155{
156 struct mmc_request mrq;
157
158 BUG_ON(host->card_busy == NULL);
159
160 memset(&mrq, 0, sizeof(struct mmc_request));
161
162 memset(cmd->resp, 0, sizeof(cmd->resp));
163 cmd->retries = retries;
164
165 mrq.cmd = cmd;
166 cmd->data = NULL;
167
168 mmc_wait_for_req(host, &mrq);
169
170 return cmd->error;
171}
172
173EXPORT_SYMBOL(mmc_wait_for_cmd);
174
175
176
177/**
178 * __mmc_claim_host - exclusively claim a host
179 * @host: mmc host to claim
180 * @card: mmc card to claim host for
181 *
182 * Claim a host for a set of operations. If a valid card
183 * is passed and this wasn't the last card selected, select
184 * the card before returning.
185 *
186 * Note: you should use mmc_card_claim_host or mmc_claim_host.
187 */
188int __mmc_claim_host(struct mmc_host *host, struct mmc_card *card)
189{
190 DECLARE_WAITQUEUE(wait, current);
191 unsigned long flags;
192 int err = 0;
193
194 add_wait_queue(&host->wq, &wait);
195 spin_lock_irqsave(&host->lock, flags);
196 while (1) {
197 set_current_state(TASK_UNINTERRUPTIBLE);
198 if (host->card_busy == NULL)
199 break;
200 spin_unlock_irqrestore(&host->lock, flags);
201 schedule();
202 spin_lock_irqsave(&host->lock, flags);
203 }
204 set_current_state(TASK_RUNNING);
205 host->card_busy = card;
206 spin_unlock_irqrestore(&host->lock, flags);
207 remove_wait_queue(&host->wq, &wait);
208
209 if (card != (void *)-1 && host->card_selected != card) {
210 struct mmc_command cmd;
211
212 host->card_selected = card;
213
214 cmd.opcode = MMC_SELECT_CARD;
215 cmd.arg = card->rca << 16;
216 cmd.flags = MMC_RSP_R1;
217
218 err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
219 }
220
221 return err;
222}
223
224EXPORT_SYMBOL(__mmc_claim_host);
225
226/**
227 * mmc_release_host - release a host
228 * @host: mmc host to release
229 *
230 * Release a MMC host, allowing others to claim the host
231 * for their operations.
232 */
233void mmc_release_host(struct mmc_host *host)
234{
235 unsigned long flags;
236
237 BUG_ON(host->card_busy == NULL);
238
239 spin_lock_irqsave(&host->lock, flags);
240 host->card_busy = NULL;
241 spin_unlock_irqrestore(&host->lock, flags);
242
243 wake_up(&host->wq);
244}
245
246EXPORT_SYMBOL(mmc_release_host);
247
248/*
249 * Ensure that no card is selected.
250 */
251static void mmc_deselect_cards(struct mmc_host *host)
252{
253 struct mmc_command cmd;
254
255 if (host->card_selected) {
256 host->card_selected = NULL;
257
258 cmd.opcode = MMC_SELECT_CARD;
259 cmd.arg = 0;
260 cmd.flags = MMC_RSP_NONE;
261
262 mmc_wait_for_cmd(host, &cmd, 0);
263 }
264}
265
266
267static inline void mmc_delay(unsigned int ms)
268{
269 if (ms < HZ / 1000) {
270 yield();
271 mdelay(ms);
272 } else {
273 msleep_interruptible (ms);
274 }
275}
276
277/*
278 * Mask off any voltages we don't support and select
279 * the lowest voltage
280 */
281static u32 mmc_select_voltage(struct mmc_host *host, u32 ocr)
282{
283 int bit;
284
285 ocr &= host->ocr_avail;
286
287 bit = ffs(ocr);
288 if (bit) {
289 bit -= 1;
290
291 ocr = 3 << bit;
292
293 host->ios.vdd = bit;
294 host->ops->set_ios(host, &host->ios);
295 } else {
296 ocr = 0;
297 }
298
299 return ocr;
300}
301
302#define UNSTUFF_BITS(resp,start,size) \
303 ({ \
304 const int __size = size; \
305 const u32 __mask = (__size < 32 ? 1 << __size : 0) - 1; \
306 const int __off = 3 - ((start) / 32); \
307 const int __shft = (start) & 31; \
308 u32 __res; \
309 \
310 __res = resp[__off] >> __shft; \
311 if (__size + __shft > 32) \
312 __res |= resp[__off-1] << ((32 - __shft) % 32); \
313 __res & __mask; \
314 })
315
316/*
317 * Given the decoded CSD structure, decode the raw CID to our CID structure.
318 */
319static void mmc_decode_cid(struct mmc_card *card)
320{
321 u32 *resp = card->raw_cid;
322
323 memset(&card->cid, 0, sizeof(struct mmc_cid));
324
325 /*
326 * The selection of the format here is guesswork based upon
327 * information people have sent to date.
328 */
329 switch (card->csd.mmca_vsn) {
330 case 0: /* MMC v1.? */
331 case 1: /* MMC v1.4 */
332 card->cid.manfid = UNSTUFF_BITS(resp, 104, 24);
333 card->cid.prod_name[0] = UNSTUFF_BITS(resp, 96, 8);
334 card->cid.prod_name[1] = UNSTUFF_BITS(resp, 88, 8);
335 card->cid.prod_name[2] = UNSTUFF_BITS(resp, 80, 8);
336 card->cid.prod_name[3] = UNSTUFF_BITS(resp, 72, 8);
337 card->cid.prod_name[4] = UNSTUFF_BITS(resp, 64, 8);
338 card->cid.prod_name[5] = UNSTUFF_BITS(resp, 56, 8);
339 card->cid.prod_name[6] = UNSTUFF_BITS(resp, 48, 8);
340 card->cid.hwrev = UNSTUFF_BITS(resp, 44, 4);
341 card->cid.fwrev = UNSTUFF_BITS(resp, 40, 4);
342 card->cid.serial = UNSTUFF_BITS(resp, 16, 24);
343 card->cid.month = UNSTUFF_BITS(resp, 12, 4);
344 card->cid.year = UNSTUFF_BITS(resp, 8, 4) + 1997;
345 break;
346
347 case 2: /* MMC v2.x ? */
348 case 3: /* MMC v3.x ? */
349 card->cid.manfid = UNSTUFF_BITS(resp, 120, 8);
350 card->cid.oemid = UNSTUFF_BITS(resp, 104, 16);
351 card->cid.prod_name[0] = UNSTUFF_BITS(resp, 96, 8);
352 card->cid.prod_name[1] = UNSTUFF_BITS(resp, 88, 8);
353 card->cid.prod_name[2] = UNSTUFF_BITS(resp, 80, 8);
354 card->cid.prod_name[3] = UNSTUFF_BITS(resp, 72, 8);
355 card->cid.prod_name[4] = UNSTUFF_BITS(resp, 64, 8);
356 card->cid.prod_name[5] = UNSTUFF_BITS(resp, 56, 8);
357 card->cid.serial = UNSTUFF_BITS(resp, 16, 32);
358 card->cid.month = UNSTUFF_BITS(resp, 12, 4);
359 card->cid.year = UNSTUFF_BITS(resp, 8, 4) + 1997;
360 break;
361
362 default:
363 printk("%s: card has unknown MMCA version %d\n",
364 card->host->host_name, card->csd.mmca_vsn);
365 mmc_card_set_bad(card);
366 break;
367 }
368}
369
370/*
371 * Given a 128-bit response, decode to our card CSD structure.
372 */
373static void mmc_decode_csd(struct mmc_card *card)
374{
375 struct mmc_csd *csd = &card->csd;
376 unsigned int e, m, csd_struct;
377 u32 *resp = card->raw_csd;
378
379 /*
380 * We only understand CSD structure v1.1 and v2.
381 * v2 has extra information in bits 15, 11 and 10.
382 */
383 csd_struct = UNSTUFF_BITS(resp, 126, 2);
384 if (csd_struct != 1 && csd_struct != 2) {
385 printk("%s: unrecognised CSD structure version %d\n",
386 card->host->host_name, csd_struct);
387 mmc_card_set_bad(card);
388 return;
389 }
390
391 csd->mmca_vsn = UNSTUFF_BITS(resp, 122, 4);
392 m = UNSTUFF_BITS(resp, 115, 4);
393 e = UNSTUFF_BITS(resp, 112, 3);
394 csd->tacc_ns = (tacc_exp[e] * tacc_mant[m] + 9) / 10;
395 csd->tacc_clks = UNSTUFF_BITS(resp, 104, 8) * 100;
396
397 m = UNSTUFF_BITS(resp, 99, 4);
398 e = UNSTUFF_BITS(resp, 96, 3);
399 csd->max_dtr = tran_exp[e] * tran_mant[m];
400 csd->cmdclass = UNSTUFF_BITS(resp, 84, 12);
401
402 e = UNSTUFF_BITS(resp, 47, 3);
403 m = UNSTUFF_BITS(resp, 62, 12);
404 csd->capacity = (1 + m) << (e + 2);
405
406 csd->read_blkbits = UNSTUFF_BITS(resp, 80, 4);
407}
408
409/*
410 * Locate a MMC card on this MMC host given a raw CID.
411 */
412static struct mmc_card *mmc_find_card(struct mmc_host *host, u32 *raw_cid)
413{
414 struct mmc_card *card;
415
416 list_for_each_entry(card, &host->cards, node) {
417 if (memcmp(card->raw_cid, raw_cid, sizeof(card->raw_cid)) == 0)
418 return card;
419 }
420 return NULL;
421}
422
423/*
424 * Allocate a new MMC card, and assign a unique RCA.
425 */
426static struct mmc_card *
427mmc_alloc_card(struct mmc_host *host, u32 *raw_cid, unsigned int *frca)
428{
429 struct mmc_card *card, *c;
430 unsigned int rca = *frca;
431
432 card = kmalloc(sizeof(struct mmc_card), GFP_KERNEL);
433 if (!card)
434 return ERR_PTR(-ENOMEM);
435
436 mmc_init_card(card, host);
437 memcpy(card->raw_cid, raw_cid, sizeof(card->raw_cid));
438
439 again:
440 list_for_each_entry(c, &host->cards, node)
441 if (c->rca == rca) {
442 rca++;
443 goto again;
444 }
445
446 card->rca = rca;
447
448 *frca = rca;
449
450 return card;
451}
452
453/*
454 * Tell attached cards to go to IDLE state
455 */
456static void mmc_idle_cards(struct mmc_host *host)
457{
458 struct mmc_command cmd;
459
460 cmd.opcode = MMC_GO_IDLE_STATE;
461 cmd.arg = 0;
462 cmd.flags = MMC_RSP_NONE;
463
464 mmc_wait_for_cmd(host, &cmd, 0);
465
466 mmc_delay(1);
467}
468
469/*
470 * Apply power to the MMC stack.
471 */
472static void mmc_power_up(struct mmc_host *host)
473{
474 int bit = fls(host->ocr_avail) - 1;
475
476 host->ios.vdd = bit;
477 host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
478 host->ios.power_mode = MMC_POWER_UP;
479 host->ops->set_ios(host, &host->ios);
480
481 mmc_delay(1);
482
483 host->ios.clock = host->f_min;
484 host->ios.power_mode = MMC_POWER_ON;
485 host->ops->set_ios(host, &host->ios);
486
487 mmc_delay(2);
488}
489
490static void mmc_power_off(struct mmc_host *host)
491{
492 host->ios.clock = 0;
493 host->ios.vdd = 0;
494 host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
495 host->ios.power_mode = MMC_POWER_OFF;
496 host->ops->set_ios(host, &host->ios);
497}
498
499static int mmc_send_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr)
500{
501 struct mmc_command cmd;
502 int i, err = 0;
503
504 cmd.opcode = MMC_SEND_OP_COND;
505 cmd.arg = ocr;
506 cmd.flags = MMC_RSP_R3;
507
508 for (i = 100; i; i--) {
509 err = mmc_wait_for_cmd(host, &cmd, 0);
510 if (err != MMC_ERR_NONE)
511 break;
512
513 if (cmd.resp[0] & MMC_CARD_BUSY || ocr == 0)
514 break;
515
516 err = MMC_ERR_TIMEOUT;
517
518 mmc_delay(10);
519 }
520
521 if (rocr)
522 *rocr = cmd.resp[0];
523
524 return err;
525}
526
527/*
528 * Discover cards by requesting their CID. If this command
529 * times out, it is not an error; there are no further cards
530 * to be discovered. Add new cards to the list.
531 *
532 * Create a mmc_card entry for each discovered card, assigning
533 * it an RCA, and save the raw CID for decoding later.
534 */
535static void mmc_discover_cards(struct mmc_host *host)
536{
537 struct mmc_card *card;
538 unsigned int first_rca = 1, err;
539
540 while (1) {
541 struct mmc_command cmd;
542
543 cmd.opcode = MMC_ALL_SEND_CID;
544 cmd.arg = 0;
545 cmd.flags = MMC_RSP_R2;
546
547 err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
548 if (err == MMC_ERR_TIMEOUT) {
549 err = MMC_ERR_NONE;
550 break;
551 }
552 if (err != MMC_ERR_NONE) {
553 printk(KERN_ERR "%s: error requesting CID: %d\n",
554 host->host_name, err);
555 break;
556 }
557
558 card = mmc_find_card(host, cmd.resp);
559 if (!card) {
560 card = mmc_alloc_card(host, cmd.resp, &first_rca);
561 if (IS_ERR(card)) {
562 err = PTR_ERR(card);
563 break;
564 }
565 list_add(&card->node, &host->cards);
566 }
567
568 card->state &= ~MMC_STATE_DEAD;
569
570 cmd.opcode = MMC_SET_RELATIVE_ADDR;
571 cmd.arg = card->rca << 16;
572 cmd.flags = MMC_RSP_R1;
573
574 err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
575 if (err != MMC_ERR_NONE)
576 mmc_card_set_dead(card);
577 }
578}
579
580static void mmc_read_csds(struct mmc_host *host)
581{
582 struct mmc_card *card;
583
584 list_for_each_entry(card, &host->cards, node) {
585 struct mmc_command cmd;
586 int err;
587
588 if (card->state & (MMC_STATE_DEAD|MMC_STATE_PRESENT))
589 continue;
590
591 cmd.opcode = MMC_SEND_CSD;
592 cmd.arg = card->rca << 16;
593 cmd.flags = MMC_RSP_R2;
594
595 err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
596 if (err != MMC_ERR_NONE) {
597 mmc_card_set_dead(card);
598 continue;
599 }
600
601 memcpy(card->raw_csd, cmd.resp, sizeof(card->raw_csd));
602
603 mmc_decode_csd(card);
604 mmc_decode_cid(card);
605 }
606}
607
608static unsigned int mmc_calculate_clock(struct mmc_host *host)
609{
610 struct mmc_card *card;
611 unsigned int max_dtr = host->f_max;
612
613 list_for_each_entry(card, &host->cards, node)
614 if (!mmc_card_dead(card) && max_dtr > card->csd.max_dtr)
615 max_dtr = card->csd.max_dtr;
616
617 DBG("MMC: selected %d.%03dMHz transfer rate\n",
618 max_dtr / 1000000, (max_dtr / 1000) % 1000);
619
620 return max_dtr;
621}
622
623/*
624 * Check whether cards we already know about are still present.
625 * We do this by requesting status, and checking whether a card
626 * responds.
627 *
628 * A request for status does not cause a state change in data
629 * transfer mode.
630 */
631static void mmc_check_cards(struct mmc_host *host)
632{
633 struct list_head *l, *n;
634
635 mmc_deselect_cards(host);
636
637 list_for_each_safe(l, n, &host->cards) {
638 struct mmc_card *card = mmc_list_to_card(l);
639 struct mmc_command cmd;
640 int err;
641
642 cmd.opcode = MMC_SEND_STATUS;
643 cmd.arg = card->rca << 16;
644 cmd.flags = MMC_RSP_R1;
645
646 err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
647 if (err == MMC_ERR_NONE)
648 continue;
649
650 mmc_card_set_dead(card);
651 }
652}
653
654static void mmc_setup(struct mmc_host *host)
655{
656 if (host->ios.power_mode != MMC_POWER_ON) {
657 int err;
658 u32 ocr;
659
660 mmc_power_up(host);
661 mmc_idle_cards(host);
662
663 err = mmc_send_op_cond(host, 0, &ocr);
664 if (err != MMC_ERR_NONE)
665 return;
666
667 host->ocr = mmc_select_voltage(host, ocr);
668
669 /*
670 * Since we're changing the OCR value, we seem to
671 * need to tell some cards to go back to the idle
672 * state. We wait 1ms to give cards time to
673 * respond.
674 */
675 if (host->ocr)
676 mmc_idle_cards(host);
677 } else {
678 host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
679 host->ios.clock = host->f_min;
680 host->ops->set_ios(host, &host->ios);
681
682 /*
683 * We should remember the OCR mask from the existing
684 * cards, and detect the new cards OCR mask, combine
685 * the two and re-select the VDD. However, if we do
686 * change VDD, we should do an idle, and then do a
687 * full re-initialisation. We would need to notify
688 * drivers so that they can re-setup the cards as
689 * well, while keeping their queues at bay.
690 *
691 * For the moment, we take the easy way out - if the
692 * new cards don't like our currently selected VDD,
693 * they drop off the bus.
694 */
695 }
696
697 if (host->ocr == 0)
698 return;
699
700 /*
701 * Send the selected OCR multiple times... until the cards
702 * all get the idea that they should be ready for CMD2.
703 * (My SanDisk card seems to need this.)
704 */
705 mmc_send_op_cond(host, host->ocr, NULL);
706
707 mmc_discover_cards(host);
708
709 /*
710 * Ok, now switch to push-pull mode.
711 */
712 host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
713 host->ops->set_ios(host, &host->ios);
714
715 mmc_read_csds(host);
716}
717
718
719/**
720 * mmc_detect_change - process change of state on a MMC socket
721 * @host: host which changed state.
722 *
723 * All we know is that card(s) have been inserted or removed
724 * from the socket(s). We don't know which socket or cards.
725 */
726void mmc_detect_change(struct mmc_host *host)
727{
728 schedule_work(&host->detect);
729}
730
731EXPORT_SYMBOL(mmc_detect_change);
732
733
734static void mmc_rescan(void *data)
735{
736 struct mmc_host *host = data;
737 struct list_head *l, *n;
738
739 mmc_claim_host(host);
740
741 if (host->ios.power_mode == MMC_POWER_ON)
742 mmc_check_cards(host);
743
744 mmc_setup(host);
745
746 if (!list_empty(&host->cards)) {
747 /*
748 * (Re-)calculate the fastest clock rate which the
749 * attached cards and the host support.
750 */
751 host->ios.clock = mmc_calculate_clock(host);
752 host->ops->set_ios(host, &host->ios);
753 }
754
755 mmc_release_host(host);
756
757 list_for_each_safe(l, n, &host->cards) {
758 struct mmc_card *card = mmc_list_to_card(l);
759
760 /*
761 * If this is a new and good card, register it.
762 */
763 if (!mmc_card_present(card) && !mmc_card_dead(card)) {
764 if (mmc_register_card(card))
765 mmc_card_set_dead(card);
766 else
767 mmc_card_set_present(card);
768 }
769
770 /*
771 * If this card is dead, destroy it.
772 */
773 if (mmc_card_dead(card)) {
774 list_del(&card->node);
775 mmc_remove_card(card);
776 }
777 }
778
779 /*
780 * If we discover that there are no cards on the
781 * bus, turn off the clock and power down.
782 */
783 if (list_empty(&host->cards))
784 mmc_power_off(host);
785}
786
787
788/**
789 * mmc_alloc_host - initialise the per-host structure.
790 * @extra: sizeof private data structure
791 * @dev: pointer to host device model structure
792 *
793 * Initialise the per-host structure.
794 */
795struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
796{
797 struct mmc_host *host;
798
799 host = kmalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL);
800 if (host) {
801 memset(host, 0, sizeof(struct mmc_host) + extra);
802
803 spin_lock_init(&host->lock);
804 init_waitqueue_head(&host->wq);
805 INIT_LIST_HEAD(&host->cards);
806 INIT_WORK(&host->detect, mmc_rescan, host);
807
808 host->dev = dev;
809
810 /*
811 * By default, hosts do not support SGIO or large requests.
812 * They have to set these according to their abilities.
813 */
814 host->max_hw_segs = 1;
815 host->max_phys_segs = 1;
816 host->max_sectors = 1 << (PAGE_CACHE_SHIFT - 9);
817 host->max_seg_size = PAGE_CACHE_SIZE;
818 }
819
820 return host;
821}
822
823EXPORT_SYMBOL(mmc_alloc_host);
824
825/**
826 * mmc_add_host - initialise host hardware
827 * @host: mmc host
828 */
829int mmc_add_host(struct mmc_host *host)
830{
831 static unsigned int host_num;
832
833 snprintf(host->host_name, sizeof(host->host_name),
834 "mmc%d", host_num++);
835
836 mmc_power_off(host);
837 mmc_detect_change(host);
838
839 return 0;
840}
841
842EXPORT_SYMBOL(mmc_add_host);
843
844/**
845 * mmc_remove_host - remove host hardware
846 * @host: mmc host
847 *
848 * Unregister and remove all cards associated with this host,
849 * and power down the MMC bus.
850 */
851void mmc_remove_host(struct mmc_host *host)
852{
853 struct list_head *l, *n;
854
855 list_for_each_safe(l, n, &host->cards) {
856 struct mmc_card *card = mmc_list_to_card(l);
857
858 mmc_remove_card(card);
859 }
860
861 mmc_power_off(host);
862}
863
864EXPORT_SYMBOL(mmc_remove_host);
865
866/**
867 * mmc_free_host - free the host structure
868 * @host: mmc host
869 *
870 * Free the host once all references to it have been dropped.
871 */
872void mmc_free_host(struct mmc_host *host)
873{
874 flush_scheduled_work();
875 kfree(host);
876}
877
878EXPORT_SYMBOL(mmc_free_host);
879
880#ifdef CONFIG_PM
881
882/**
883 * mmc_suspend_host - suspend a host
884 * @host: mmc host
885 * @state: suspend mode (PM_SUSPEND_xxx)
886 */
887int mmc_suspend_host(struct mmc_host *host, u32 state)
888{
889 mmc_claim_host(host);
890 mmc_deselect_cards(host);
891 mmc_power_off(host);
892 mmc_release_host(host);
893
894 return 0;
895}
896
897EXPORT_SYMBOL(mmc_suspend_host);
898
899/**
900 * mmc_resume_host - resume a previously suspended host
901 * @host: mmc host
902 */
903int mmc_resume_host(struct mmc_host *host)
904{
905 mmc_detect_change(host);
906
907 return 0;
908}
909
910EXPORT_SYMBOL(mmc_resume_host);
911
912#endif
913
914MODULE_LICENSE("GPL");
generated by cgit v1.2.2 (git 2.25.0) at 2025-10-27 12:42:15 -0400