2 * linux/drivers/mmc/core/core.c
4 * Copyright (C) 2003-2004 Russell King, All Rights Reserved.
5 * SD support Copyright (C) 2004 Ian Molton, All Rights Reserved.
6 * Copyright (C) 2005-2007 Pierre Ossman, All Rights Reserved.
7 * MMCv4 support Copyright (C) 2006 Philip Langdale, All Rights Reserved.
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.
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 <asm/scatterlist.h>
22 #include <linux/scatterlist.h>
24 #include <linux/mmc/card.h>
25 #include <linux/mmc/host.h>
26 #include <linux/mmc/mmc.h>
27 #include <linux/mmc/sd.h>
36 extern int mmc_attach_mmc(struct mmc_host *host, u32 ocr);
37 extern int mmc_attach_sd(struct mmc_host *host, u32 ocr);
39 static struct workqueue_struct *workqueue;
42 * Internal function. Schedule delayed work in the MMC work queue.
44 static int mmc_schedule_delayed_work(struct delayed_work *work,
47 return queue_delayed_work(workqueue, work, delay);
51 * Internal function. Flush all scheduled work from the MMC work queue.
53 static void mmc_flush_scheduled_work(void)
55 flush_workqueue(workqueue);
59 * mmc_request_done - finish processing an MMC request
60 * @host: MMC host which completed request
61 * @mrq: MMC request which request
63 * MMC drivers should call this function when they have completed
64 * their processing of a request.
66 void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
68 struct mmc_command *cmd = mrq->cmd;
71 if (err && cmd->retries) {
72 pr_debug("%s: req failed (CMD%u): %d, retrying...\n",
73 mmc_hostname(host), cmd->opcode, err);
77 host->ops->request(host, mrq);
79 pr_debug("%s: req done (CMD%u): %d: %08x %08x %08x %08x\n",
80 mmc_hostname(host), cmd->opcode, err,
81 cmd->resp[0], cmd->resp[1],
82 cmd->resp[2], cmd->resp[3]);
85 pr_debug("%s: %d bytes transferred: %d\n",
87 mrq->data->bytes_xfered, mrq->data->error);
91 pr_debug("%s: (CMD%u): %d: %08x %08x %08x %08x\n",
92 mmc_hostname(host), mrq->stop->opcode,
94 mrq->stop->resp[0], mrq->stop->resp[1],
95 mrq->stop->resp[2], mrq->stop->resp[3]);
103 EXPORT_SYMBOL(mmc_request_done);
106 mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
108 #ifdef CONFIG_MMC_DEBUG
112 pr_debug("%s: starting CMD%u arg %08x flags %08x\n",
113 mmc_hostname(host), mrq->cmd->opcode,
114 mrq->cmd->arg, mrq->cmd->flags);
117 pr_debug("%s: blksz %d blocks %d flags %08x "
118 "tsac %d ms nsac %d\n",
119 mmc_hostname(host), mrq->data->blksz,
120 mrq->data->blocks, mrq->data->flags,
121 mrq->data->timeout_ns / 10000000,
122 mrq->data->timeout_clks);
126 pr_debug("%s: CMD%u arg %08x flags %08x\n",
127 mmc_hostname(host), mrq->stop->opcode,
128 mrq->stop->arg, mrq->stop->flags);
131 WARN_ON(!host->claimed);
136 BUG_ON(mrq->data->blksz > host->max_blk_size);
137 BUG_ON(mrq->data->blocks > host->max_blk_count);
138 BUG_ON(mrq->data->blocks * mrq->data->blksz >
141 #ifdef CONFIG_MMC_DEBUG
143 for (i = 0;i < mrq->data->sg_len;i++)
144 sz += mrq->data->sg[i].length;
145 BUG_ON(sz != mrq->data->blocks * mrq->data->blksz);
148 mrq->cmd->data = mrq->data;
149 mrq->data->error = 0;
150 mrq->data->mrq = mrq;
152 mrq->data->stop = mrq->stop;
153 mrq->stop->error = 0;
154 mrq->stop->mrq = mrq;
157 host->ops->request(host, mrq);
160 static void mmc_wait_done(struct mmc_request *mrq)
162 complete(mrq->done_data);
166 * mmc_wait_for_req - start a request and wait for completion
167 * @host: MMC host to start command
168 * @mrq: MMC request to start
170 * Start a new MMC custom command request for a host, and wait
171 * for the command to complete. Does not attempt to parse the
174 void mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq)
176 DECLARE_COMPLETION_ONSTACK(complete);
178 mrq->done_data = &complete;
179 mrq->done = mmc_wait_done;
181 mmc_start_request(host, mrq);
183 wait_for_completion(&complete);
186 EXPORT_SYMBOL(mmc_wait_for_req);
189 * mmc_wait_for_cmd - start a command and wait for completion
190 * @host: MMC host to start command
191 * @cmd: MMC command to start
192 * @retries: maximum number of retries
194 * Start a new MMC command for a host, and wait for the command
195 * to complete. Return any error that occurred while the command
196 * was executing. Do not attempt to parse the response.
198 int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries)
200 struct mmc_request mrq;
202 BUG_ON(!host->claimed);
204 memset(&mrq, 0, sizeof(struct mmc_request));
206 memset(cmd->resp, 0, sizeof(cmd->resp));
207 cmd->retries = retries;
212 mmc_wait_for_req(host, &mrq);
217 EXPORT_SYMBOL(mmc_wait_for_cmd);
220 * mmc_set_data_timeout - set the timeout for a data command
221 * @data: data phase for command
222 * @card: the MMC card associated with the data transfer
223 * @write: flag to differentiate reads from writes
225 * Computes the data timeout parameters according to the
226 * correct algorithm given the card type.
228 void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card,
234 * SD cards use a 100 multiplier rather than 10
236 mult = mmc_card_sd(card) ? 100 : 10;
239 * Scale up the multiplier (and therefore the timeout) by
240 * the r2w factor for writes.
243 mult <<= card->csd.r2w_factor;
245 data->timeout_ns = card->csd.tacc_ns * mult;
246 data->timeout_clks = card->csd.tacc_clks * mult;
249 * SD cards also have an upper limit on the timeout.
251 if (mmc_card_sd(card)) {
252 unsigned int timeout_us, limit_us;
254 timeout_us = data->timeout_ns / 1000;
255 timeout_us += data->timeout_clks * 1000 /
256 (card->host->ios.clock / 1000);
264 * SDHC cards always use these fixed values.
266 if (timeout_us > limit_us || mmc_card_blockaddr(card)) {
267 data->timeout_ns = limit_us * 1000;
268 data->timeout_clks = 0;
272 EXPORT_SYMBOL(mmc_set_data_timeout);
275 * mmc_claim_host - exclusively claim a host
276 * @host: mmc host to claim
278 * Claim a host for a set of operations.
280 void mmc_claim_host(struct mmc_host *host)
282 DECLARE_WAITQUEUE(wait, current);
287 add_wait_queue(&host->wq, &wait);
288 spin_lock_irqsave(&host->lock, flags);
290 set_current_state(TASK_UNINTERRUPTIBLE);
293 spin_unlock_irqrestore(&host->lock, flags);
295 spin_lock_irqsave(&host->lock, flags);
297 set_current_state(TASK_RUNNING);
299 spin_unlock_irqrestore(&host->lock, flags);
300 remove_wait_queue(&host->wq, &wait);
303 EXPORT_SYMBOL(mmc_claim_host);
306 * mmc_release_host - release a host
307 * @host: mmc host to release
309 * Release a MMC host, allowing others to claim the host
310 * for their operations.
312 void mmc_release_host(struct mmc_host *host)
316 BUG_ON(!host->claimed);
318 spin_lock_irqsave(&host->lock, flags);
320 spin_unlock_irqrestore(&host->lock, flags);
325 EXPORT_SYMBOL(mmc_release_host);
328 * Internal function that does the actual ios call to the host driver,
329 * optionally printing some debug output.
331 static inline void mmc_set_ios(struct mmc_host *host)
333 struct mmc_ios *ios = &host->ios;
335 pr_debug("%s: clock %uHz busmode %u powermode %u cs %u Vdd %u "
336 "width %u timing %u\n",
337 mmc_hostname(host), ios->clock, ios->bus_mode,
338 ios->power_mode, ios->chip_select, ios->vdd,
339 ios->bus_width, ios->timing);
341 host->ops->set_ios(host, ios);
345 * Control chip select pin on a host.
347 void mmc_set_chip_select(struct mmc_host *host, int mode)
349 host->ios.chip_select = mode;
354 * Sets the host clock to the highest possible frequency that
357 void mmc_set_clock(struct mmc_host *host, unsigned int hz)
359 WARN_ON(hz < host->f_min);
361 if (hz > host->f_max)
364 host->ios.clock = hz;
369 * Change the bus mode (open drain/push-pull) of a host.
371 void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode)
373 host->ios.bus_mode = mode;
378 * Change data bus width of a host.
380 void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
382 host->ios.bus_width = width;
387 * Mask off any voltages we don't support and select
390 u32 mmc_select_voltage(struct mmc_host *host, u32 ocr)
394 ocr &= host->ocr_avail;
412 * Select timing parameters for host.
414 void mmc_set_timing(struct mmc_host *host, unsigned int timing)
416 host->ios.timing = timing;
421 * Apply power to the MMC stack. This is a two-stage process.
422 * First, we enable power to the card without the clock running.
423 * We then wait a bit for the power to stabilise. Finally,
424 * enable the bus drivers and clock to the card.
426 * We must _NOT_ enable the clock prior to power stablising.
428 * If a host does all the power sequencing itself, ignore the
429 * initial MMC_POWER_UP stage.
431 static void mmc_power_up(struct mmc_host *host)
433 int bit = fls(host->ocr_avail) - 1;
436 host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
437 host->ios.chip_select = MMC_CS_DONTCARE;
438 host->ios.power_mode = MMC_POWER_UP;
439 host->ios.bus_width = MMC_BUS_WIDTH_1;
440 host->ios.timing = MMC_TIMING_LEGACY;
445 host->ios.clock = host->f_min;
446 host->ios.power_mode = MMC_POWER_ON;
452 static void mmc_power_off(struct mmc_host *host)
456 host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
457 host->ios.chip_select = MMC_CS_DONTCARE;
458 host->ios.power_mode = MMC_POWER_OFF;
459 host->ios.bus_width = MMC_BUS_WIDTH_1;
460 host->ios.timing = MMC_TIMING_LEGACY;
465 * Cleanup when the last reference to the bus operator is dropped.
467 void __mmc_release_bus(struct mmc_host *host)
470 BUG_ON(host->bus_refs);
471 BUG_ON(!host->bus_dead);
473 host->bus_ops = NULL;
477 * Increase reference count of bus operator
479 static inline void mmc_bus_get(struct mmc_host *host)
483 spin_lock_irqsave(&host->lock, flags);
485 spin_unlock_irqrestore(&host->lock, flags);
489 * Decrease reference count of bus operator and free it if
490 * it is the last reference.
492 static inline void mmc_bus_put(struct mmc_host *host)
496 spin_lock_irqsave(&host->lock, flags);
498 if ((host->bus_refs == 0) && host->bus_ops)
499 __mmc_release_bus(host);
500 spin_unlock_irqrestore(&host->lock, flags);
504 * Assign a mmc bus handler to a host. Only one bus handler may control a
505 * host at any given time.
507 void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops)
514 BUG_ON(!host->claimed);
516 spin_lock_irqsave(&host->lock, flags);
518 BUG_ON(host->bus_ops);
519 BUG_ON(host->bus_refs);
525 spin_unlock_irqrestore(&host->lock, flags);
529 * Remove the current bus handler from a host. Assumes that there are
530 * no interesting cards left, so the bus is powered down.
532 void mmc_detach_bus(struct mmc_host *host)
538 BUG_ON(!host->claimed);
539 BUG_ON(!host->bus_ops);
541 spin_lock_irqsave(&host->lock, flags);
545 spin_unlock_irqrestore(&host->lock, flags);
553 * mmc_detect_change - process change of state on a MMC socket
554 * @host: host which changed state.
555 * @delay: optional delay to wait before detection (jiffies)
557 * MMC drivers should call this when they detect a card has been
558 * inserted or removed. The MMC layer will confirm that any
559 * present card is still functional, and initialize any newly
562 void mmc_detect_change(struct mmc_host *host, unsigned long delay)
564 #ifdef CONFIG_MMC_DEBUG
566 spin_lock_irqsave(&host->lock, flags);
567 BUG_ON(host->removed);
568 spin_unlock_irqrestore(&host->lock, flags);
571 mmc_schedule_delayed_work(&host->detect, delay);
574 EXPORT_SYMBOL(mmc_detect_change);
577 void mmc_rescan(struct work_struct *work)
579 struct mmc_host *host =
580 container_of(work, struct mmc_host, detect.work);
586 if (host->bus_ops == NULL) {
588 * Only we can add a new handler, so it's safe to
589 * release the lock here.
593 mmc_claim_host(host);
598 mmc_send_if_cond(host, host->ocr_avail);
600 err = mmc_send_app_op_cond(host, 0, &ocr);
601 if (err == MMC_ERR_NONE) {
602 if (mmc_attach_sd(host, ocr))
606 * If we fail to detect any SD cards then try
607 * searching for MMC cards.
609 err = mmc_send_op_cond(host, 0, &ocr);
610 if (err == MMC_ERR_NONE) {
611 if (mmc_attach_mmc(host, ocr))
615 mmc_release_host(host);
619 if (host->bus_ops->detect && !host->bus_dead)
620 host->bus_ops->detect(host);
626 void mmc_start_host(struct mmc_host *host)
629 mmc_detect_change(host, 0);
632 void mmc_stop_host(struct mmc_host *host)
634 #ifdef CONFIG_MMC_DEBUG
636 spin_lock_irqsave(&host->lock, flags);
638 spin_unlock_irqrestore(&host->lock, flags);
641 mmc_flush_scheduled_work();
644 if (host->bus_ops && !host->bus_dead) {
645 if (host->bus_ops->remove)
646 host->bus_ops->remove(host);
648 mmc_claim_host(host);
649 mmc_detach_bus(host);
650 mmc_release_host(host);
662 * mmc_suspend_host - suspend a host
664 * @state: suspend mode (PM_SUSPEND_xxx)
666 int mmc_suspend_host(struct mmc_host *host, pm_message_t state)
668 mmc_flush_scheduled_work();
671 if (host->bus_ops && !host->bus_dead) {
672 if (host->bus_ops->suspend)
673 host->bus_ops->suspend(host);
674 if (!host->bus_ops->resume) {
675 if (host->bus_ops->remove)
676 host->bus_ops->remove(host);
678 mmc_claim_host(host);
679 mmc_detach_bus(host);
680 mmc_release_host(host);
690 EXPORT_SYMBOL(mmc_suspend_host);
693 * mmc_resume_host - resume a previously suspended host
696 int mmc_resume_host(struct mmc_host *host)
699 if (host->bus_ops && !host->bus_dead) {
701 BUG_ON(!host->bus_ops->resume);
702 host->bus_ops->resume(host);
707 * We add a slight delay here so that resume can progress
710 mmc_detect_change(host, 1);
715 EXPORT_SYMBOL(mmc_resume_host);
719 static int __init mmc_init(void)
723 workqueue = create_singlethread_workqueue("kmmcd");
727 ret = mmc_register_bus();
729 ret = mmc_register_host_class();
731 mmc_unregister_bus();
736 static void __exit mmc_exit(void)
738 mmc_unregister_host_class();
739 mmc_unregister_bus();
740 destroy_workqueue(workqueue);
743 module_init(mmc_init);
744 module_exit(mmc_exit);
746 MODULE_LICENSE("GPL");