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 pr_debug("%s: req done (CMD%u): %d/%d/%d: %08x %08x %08x %08x\n",
72 mmc_hostname(host), cmd->opcode, err,
73 mrq->data ? mrq->data->error : 0,
74 mrq->stop ? mrq->stop->error : 0,
75 cmd->resp[0], cmd->resp[1], cmd->resp[2], cmd->resp[3]);
77 if (err && cmd->retries) {
80 host->ops->request(host, mrq);
81 } else if (mrq->done) {
86 EXPORT_SYMBOL(mmc_request_done);
89 * mmc_start_request - start a command on a host
90 * @host: MMC host to start command on
91 * @mrq: MMC request to start
93 * Queue a command on the specified host. We expect the
94 * caller to be holding the host lock with interrupts disabled.
97 mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
99 #ifdef CONFIG_MMC_DEBUG
103 pr_debug("%s: starting CMD%u arg %08x flags %08x\n",
104 mmc_hostname(host), mrq->cmd->opcode,
105 mrq->cmd->arg, mrq->cmd->flags);
107 WARN_ON(!host->claimed);
112 BUG_ON(mrq->data->blksz > host->max_blk_size);
113 BUG_ON(mrq->data->blocks > host->max_blk_count);
114 BUG_ON(mrq->data->blocks * mrq->data->blksz >
117 #ifdef CONFIG_MMC_DEBUG
119 for (i = 0;i < mrq->data->sg_len;i++)
120 sz += mrq->data->sg[i].length;
121 BUG_ON(sz != mrq->data->blocks * mrq->data->blksz);
124 mrq->cmd->data = mrq->data;
125 mrq->data->error = 0;
126 mrq->data->mrq = mrq;
128 mrq->data->stop = mrq->stop;
129 mrq->stop->error = 0;
130 mrq->stop->mrq = mrq;
133 host->ops->request(host, mrq);
136 EXPORT_SYMBOL(mmc_start_request);
138 static void mmc_wait_done(struct mmc_request *mrq)
140 complete(mrq->done_data);
144 * mmc_wait_for_req - start a request and wait for completion
145 * @host: MMC host to start command
146 * @mrq: MMC request to start
148 * Start a new MMC custom command request for a host, and wait
149 * for the command to complete. Does not attempt to parse the
152 void mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq)
154 DECLARE_COMPLETION_ONSTACK(complete);
156 mrq->done_data = &complete;
157 mrq->done = mmc_wait_done;
159 mmc_start_request(host, mrq);
161 wait_for_completion(&complete);
164 EXPORT_SYMBOL(mmc_wait_for_req);
167 * mmc_wait_for_cmd - start a command and wait for completion
168 * @host: MMC host to start command
169 * @cmd: MMC command to start
170 * @retries: maximum number of retries
172 * Start a new MMC command for a host, and wait for the command
173 * to complete. Return any error that occurred while the command
174 * was executing. Do not attempt to parse the response.
176 int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries)
178 struct mmc_request mrq;
180 BUG_ON(!host->claimed);
182 memset(&mrq, 0, sizeof(struct mmc_request));
184 memset(cmd->resp, 0, sizeof(cmd->resp));
185 cmd->retries = retries;
190 mmc_wait_for_req(host, &mrq);
195 EXPORT_SYMBOL(mmc_wait_for_cmd);
198 * mmc_set_data_timeout - set the timeout for a data command
199 * @data: data phase for command
200 * @card: the MMC card associated with the data transfer
201 * @write: flag to differentiate reads from writes
203 * Computes the data timeout parameters according to the
204 * correct algorithm given the card type.
206 void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card,
212 * SD cards use a 100 multiplier rather than 10
214 mult = mmc_card_sd(card) ? 100 : 10;
217 * Scale up the multiplier (and therefore the timeout) by
218 * the r2w factor for writes.
221 mult <<= card->csd.r2w_factor;
223 data->timeout_ns = card->csd.tacc_ns * mult;
224 data->timeout_clks = card->csd.tacc_clks * mult;
227 * SD cards also have an upper limit on the timeout.
229 if (mmc_card_sd(card)) {
230 unsigned int timeout_us, limit_us;
232 timeout_us = data->timeout_ns / 1000;
233 timeout_us += data->timeout_clks * 1000 /
234 (card->host->ios.clock / 1000);
242 * SDHC cards always use these fixed values.
244 if (timeout_us > limit_us || mmc_card_blockaddr(card)) {
245 data->timeout_ns = limit_us * 1000;
246 data->timeout_clks = 0;
250 EXPORT_SYMBOL(mmc_set_data_timeout);
253 * mmc_claim_host - exclusively claim a host
254 * @host: mmc host to claim
256 * Claim a host for a set of operations.
258 void mmc_claim_host(struct mmc_host *host)
260 DECLARE_WAITQUEUE(wait, current);
265 add_wait_queue(&host->wq, &wait);
266 spin_lock_irqsave(&host->lock, flags);
268 set_current_state(TASK_UNINTERRUPTIBLE);
271 spin_unlock_irqrestore(&host->lock, flags);
273 spin_lock_irqsave(&host->lock, flags);
275 set_current_state(TASK_RUNNING);
277 spin_unlock_irqrestore(&host->lock, flags);
278 remove_wait_queue(&host->wq, &wait);
281 EXPORT_SYMBOL(mmc_claim_host);
284 * mmc_release_host - release a host
285 * @host: mmc host to release
287 * Release a MMC host, allowing others to claim the host
288 * for their operations.
290 void mmc_release_host(struct mmc_host *host)
294 BUG_ON(!host->claimed);
296 spin_lock_irqsave(&host->lock, flags);
298 spin_unlock_irqrestore(&host->lock, flags);
303 EXPORT_SYMBOL(mmc_release_host);
306 * Internal function that does the actual ios call to the host driver,
307 * optionally printing some debug output.
309 static inline void mmc_set_ios(struct mmc_host *host)
311 struct mmc_ios *ios = &host->ios;
313 pr_debug("%s: clock %uHz busmode %u powermode %u cs %u Vdd %u "
314 "width %u timing %u\n",
315 mmc_hostname(host), ios->clock, ios->bus_mode,
316 ios->power_mode, ios->chip_select, ios->vdd,
317 ios->bus_width, ios->timing);
319 host->ops->set_ios(host, ios);
323 * Control chip select pin on a host.
325 void mmc_set_chip_select(struct mmc_host *host, int mode)
327 host->ios.chip_select = mode;
332 * Sets the host clock to the highest possible frequency that
335 void mmc_set_clock(struct mmc_host *host, unsigned int hz)
337 WARN_ON(hz < host->f_min);
339 if (hz > host->f_max)
342 host->ios.clock = hz;
347 * Change the bus mode (open drain/push-pull) of a host.
349 void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode)
351 host->ios.bus_mode = mode;
356 * Change data bus width of a host.
358 void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
360 host->ios.bus_width = width;
365 * Mask off any voltages we don't support and select
368 u32 mmc_select_voltage(struct mmc_host *host, u32 ocr)
372 ocr &= host->ocr_avail;
390 * Select timing parameters for host.
392 void mmc_set_timing(struct mmc_host *host, unsigned int timing)
394 host->ios.timing = timing;
399 * Apply power to the MMC stack. This is a two-stage process.
400 * First, we enable power to the card without the clock running.
401 * We then wait a bit for the power to stabilise. Finally,
402 * enable the bus drivers and clock to the card.
404 * We must _NOT_ enable the clock prior to power stablising.
406 * If a host does all the power sequencing itself, ignore the
407 * initial MMC_POWER_UP stage.
409 static void mmc_power_up(struct mmc_host *host)
411 int bit = fls(host->ocr_avail) - 1;
414 host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
415 host->ios.chip_select = MMC_CS_DONTCARE;
416 host->ios.power_mode = MMC_POWER_UP;
417 host->ios.bus_width = MMC_BUS_WIDTH_1;
418 host->ios.timing = MMC_TIMING_LEGACY;
423 host->ios.clock = host->f_min;
424 host->ios.power_mode = MMC_POWER_ON;
430 static void mmc_power_off(struct mmc_host *host)
434 host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
435 host->ios.chip_select = MMC_CS_DONTCARE;
436 host->ios.power_mode = MMC_POWER_OFF;
437 host->ios.bus_width = MMC_BUS_WIDTH_1;
438 host->ios.timing = MMC_TIMING_LEGACY;
443 * Assign a mmc bus handler to a host. Only one bus handler may control a
444 * host at any given time.
446 void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops)
453 BUG_ON(!host->claimed);
455 spin_lock_irqsave(&host->lock, flags);
457 BUG_ON(host->bus_ops);
458 BUG_ON(host->bus_refs);
464 spin_unlock_irqrestore(&host->lock, flags);
468 * Remove the current bus handler from a host. Assumes that there are
469 * no interesting cards left, so the bus is powered down.
471 void mmc_detach_bus(struct mmc_host *host)
477 BUG_ON(!host->claimed);
478 BUG_ON(!host->bus_ops);
480 spin_lock_irqsave(&host->lock, flags);
484 spin_unlock_irqrestore(&host->lock, flags);
492 * Cleanup when the last reference to the bus operator is dropped.
494 void __mmc_release_bus(struct mmc_host *host)
497 BUG_ON(host->bus_refs);
498 BUG_ON(!host->bus_dead);
500 host->bus_ops = NULL;
504 * mmc_detect_change - process change of state on a MMC socket
505 * @host: host which changed state.
506 * @delay: optional delay to wait before detection (jiffies)
508 * MMC drivers should call this when they detect a card has been
509 * inserted or removed. The MMC layer will confirm that any
510 * present card is still functional, and initialize any newly
513 void mmc_detect_change(struct mmc_host *host, unsigned long delay)
515 #ifdef CONFIG_MMC_DEBUG
517 spin_lock_irqsave(&host->lock, flags);
518 BUG_ON(host->removed);
519 spin_unlock_irqrestore(&host->lock, flags);
522 mmc_schedule_delayed_work(&host->detect, delay);
525 EXPORT_SYMBOL(mmc_detect_change);
528 void mmc_rescan(struct work_struct *work)
530 struct mmc_host *host =
531 container_of(work, struct mmc_host, detect.work);
537 if (host->bus_ops == NULL) {
539 * Only we can add a new handler, so it's safe to
540 * release the lock here.
544 mmc_claim_host(host);
549 mmc_send_if_cond(host, host->ocr_avail);
551 err = mmc_send_app_op_cond(host, 0, &ocr);
552 if (err == MMC_ERR_NONE) {
553 if (mmc_attach_sd(host, ocr))
557 * If we fail to detect any SD cards then try
558 * searching for MMC cards.
560 err = mmc_send_op_cond(host, 0, &ocr);
561 if (err == MMC_ERR_NONE) {
562 if (mmc_attach_mmc(host, ocr))
566 mmc_release_host(host);
570 if (host->bus_ops->detect && !host->bus_dead)
571 host->bus_ops->detect(host);
577 void mmc_start_host(struct mmc_host *host)
580 mmc_detect_change(host, 0);
583 void mmc_stop_host(struct mmc_host *host)
585 #ifdef CONFIG_MMC_DEBUG
587 spin_lock_irqsave(&host->lock, flags);
589 spin_unlock_irqrestore(&host->lock, flags);
592 mmc_flush_scheduled_work();
595 if (host->bus_ops && !host->bus_dead) {
596 if (host->bus_ops->remove)
597 host->bus_ops->remove(host);
599 mmc_claim_host(host);
600 mmc_detach_bus(host);
601 mmc_release_host(host);
613 * mmc_suspend_host - suspend a host
615 * @state: suspend mode (PM_SUSPEND_xxx)
617 int mmc_suspend_host(struct mmc_host *host, pm_message_t state)
619 mmc_flush_scheduled_work();
622 if (host->bus_ops && !host->bus_dead) {
623 if (host->bus_ops->suspend)
624 host->bus_ops->suspend(host);
625 if (!host->bus_ops->resume) {
626 if (host->bus_ops->remove)
627 host->bus_ops->remove(host);
629 mmc_claim_host(host);
630 mmc_detach_bus(host);
631 mmc_release_host(host);
641 EXPORT_SYMBOL(mmc_suspend_host);
644 * mmc_resume_host - resume a previously suspended host
647 int mmc_resume_host(struct mmc_host *host)
650 if (host->bus_ops && !host->bus_dead) {
652 BUG_ON(!host->bus_ops->resume);
653 host->bus_ops->resume(host);
658 * We add a slight delay here so that resume can progress
661 mmc_detect_change(host, 1);
666 EXPORT_SYMBOL(mmc_resume_host);
670 static int __init mmc_init(void)
674 workqueue = create_singlethread_workqueue("kmmcd");
678 ret = mmc_register_bus();
680 ret = mmc_register_host_class();
682 mmc_unregister_bus();
687 static void __exit mmc_exit(void)
689 mmc_unregister_host_class();
690 mmc_unregister_bus();
691 destroy_workqueue(workqueue);
694 module_init(mmc_init);
695 module_exit(mmc_exit);
697 MODULE_LICENSE("GPL");