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);
143 int mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq)
145 DECLARE_COMPLETION_ONSTACK(complete);
147 mrq->done_data = &complete;
148 mrq->done = mmc_wait_done;
150 mmc_start_request(host, mrq);
152 wait_for_completion(&complete);
157 EXPORT_SYMBOL(mmc_wait_for_req);
160 * mmc_wait_for_cmd - start a command and wait for completion
161 * @host: MMC host to start command
162 * @cmd: MMC command to start
163 * @retries: maximum number of retries
165 * Start a new MMC command for a host, and wait for the command
166 * to complete. Return any error that occurred while the command
167 * was executing. Do not attempt to parse the response.
169 int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries)
171 struct mmc_request mrq;
173 BUG_ON(!host->claimed);
175 memset(&mrq, 0, sizeof(struct mmc_request));
177 memset(cmd->resp, 0, sizeof(cmd->resp));
178 cmd->retries = retries;
183 mmc_wait_for_req(host, &mrq);
188 EXPORT_SYMBOL(mmc_wait_for_cmd);
191 * mmc_set_data_timeout - set the timeout for a data command
192 * @data: data phase for command
193 * @card: the MMC card associated with the data transfer
194 * @write: flag to differentiate reads from writes
196 void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card,
202 * SD cards use a 100 multiplier rather than 10
204 mult = mmc_card_sd(card) ? 100 : 10;
207 * Scale up the multiplier (and therefore the timeout) by
208 * the r2w factor for writes.
211 mult <<= card->csd.r2w_factor;
213 data->timeout_ns = card->csd.tacc_ns * mult;
214 data->timeout_clks = card->csd.tacc_clks * mult;
217 * SD cards also have an upper limit on the timeout.
219 if (mmc_card_sd(card)) {
220 unsigned int timeout_us, limit_us;
222 timeout_us = data->timeout_ns / 1000;
223 timeout_us += data->timeout_clks * 1000 /
224 (card->host->ios.clock / 1000);
232 * SDHC cards always use these fixed values.
234 if (timeout_us > limit_us || mmc_card_blockaddr(card)) {
235 data->timeout_ns = limit_us * 1000;
236 data->timeout_clks = 0;
240 EXPORT_SYMBOL(mmc_set_data_timeout);
243 * __mmc_claim_host - exclusively claim a host
244 * @host: mmc host to claim
245 * @card: mmc card to claim host for
247 * Claim a host for a set of operations. If a valid card
248 * is passed and this wasn't the last card selected, select
249 * the card before returning.
251 * Note: you should use mmc_card_claim_host or mmc_claim_host.
253 void mmc_claim_host(struct mmc_host *host)
255 DECLARE_WAITQUEUE(wait, current);
258 add_wait_queue(&host->wq, &wait);
259 spin_lock_irqsave(&host->lock, flags);
261 set_current_state(TASK_UNINTERRUPTIBLE);
264 spin_unlock_irqrestore(&host->lock, flags);
266 spin_lock_irqsave(&host->lock, flags);
268 set_current_state(TASK_RUNNING);
270 spin_unlock_irqrestore(&host->lock, flags);
271 remove_wait_queue(&host->wq, &wait);
274 EXPORT_SYMBOL(mmc_claim_host);
277 * mmc_release_host - release a host
278 * @host: mmc host to release
280 * Release a MMC host, allowing others to claim the host
281 * for their operations.
283 void mmc_release_host(struct mmc_host *host)
287 BUG_ON(!host->claimed);
289 spin_lock_irqsave(&host->lock, flags);
291 spin_unlock_irqrestore(&host->lock, flags);
296 EXPORT_SYMBOL(mmc_release_host);
299 * Internal function that does the actual ios call to the host driver,
300 * optionally printing some debug output.
302 static inline void mmc_set_ios(struct mmc_host *host)
304 struct mmc_ios *ios = &host->ios;
306 pr_debug("%s: clock %uHz busmode %u powermode %u cs %u Vdd %u "
307 "width %u timing %u\n",
308 mmc_hostname(host), ios->clock, ios->bus_mode,
309 ios->power_mode, ios->chip_select, ios->vdd,
310 ios->bus_width, ios->timing);
312 host->ops->set_ios(host, ios);
316 * Control chip select pin on a host.
318 void mmc_set_chip_select(struct mmc_host *host, int mode)
320 host->ios.chip_select = mode;
325 * Sets the host clock to the highest possible frequency that
328 void mmc_set_clock(struct mmc_host *host, unsigned int hz)
330 WARN_ON(hz < host->f_min);
332 if (hz > host->f_max)
335 host->ios.clock = hz;
340 * Change the bus mode (open drain/push-pull) of a host.
342 void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode)
344 host->ios.bus_mode = mode;
349 * Change data bus width of a host.
351 void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
353 host->ios.bus_width = width;
358 * Mask off any voltages we don't support and select
361 u32 mmc_select_voltage(struct mmc_host *host, u32 ocr)
365 ocr &= host->ocr_avail;
383 * Select timing parameters for host.
385 void mmc_set_timing(struct mmc_host *host, unsigned int timing)
387 host->ios.timing = timing;
392 * Apply power to the MMC stack. This is a two-stage process.
393 * First, we enable power to the card without the clock running.
394 * We then wait a bit for the power to stabilise. Finally,
395 * enable the bus drivers and clock to the card.
397 * We must _NOT_ enable the clock prior to power stablising.
399 * If a host does all the power sequencing itself, ignore the
400 * initial MMC_POWER_UP stage.
402 static void mmc_power_up(struct mmc_host *host)
404 int bit = fls(host->ocr_avail) - 1;
407 host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
408 host->ios.chip_select = MMC_CS_DONTCARE;
409 host->ios.power_mode = MMC_POWER_UP;
410 host->ios.bus_width = MMC_BUS_WIDTH_1;
411 host->ios.timing = MMC_TIMING_LEGACY;
416 host->ios.clock = host->f_min;
417 host->ios.power_mode = MMC_POWER_ON;
423 static void mmc_power_off(struct mmc_host *host)
427 host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
428 host->ios.chip_select = MMC_CS_DONTCARE;
429 host->ios.power_mode = MMC_POWER_OFF;
430 host->ios.bus_width = MMC_BUS_WIDTH_1;
431 host->ios.timing = MMC_TIMING_LEGACY;
436 * Assign a mmc bus handler to a host. Only one bus handler may control a
437 * host at any given time.
439 void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops)
446 BUG_ON(!host->claimed);
448 spin_lock_irqsave(&host->lock, flags);
450 BUG_ON(host->bus_ops);
451 BUG_ON(host->bus_refs);
457 spin_unlock_irqrestore(&host->lock, flags);
461 * Remove the current bus handler from a host. Assumes that there are
462 * no interesting cards left, so the bus is powered down.
464 void mmc_detach_bus(struct mmc_host *host)
470 BUG_ON(!host->claimed);
471 BUG_ON(!host->bus_ops);
473 spin_lock_irqsave(&host->lock, flags);
477 spin_unlock_irqrestore(&host->lock, flags);
485 * Cleanup when the last reference to the bus operator is dropped.
487 void __mmc_release_bus(struct mmc_host *host)
490 BUG_ON(host->bus_refs);
491 BUG_ON(!host->bus_dead);
493 host->bus_ops = NULL;
497 * mmc_detect_change - process change of state on a MMC socket
498 * @host: host which changed state.
499 * @delay: optional delay to wait before detection (jiffies)
501 * All we know is that card(s) have been inserted or removed
502 * from the socket(s). We don't know which socket or cards.
504 void mmc_detect_change(struct mmc_host *host, unsigned long delay)
506 #ifdef CONFIG_MMC_DEBUG
508 spin_lock_irqsave(&host->lock, flags);
509 BUG_ON(host->removed);
510 spin_unlock_irqrestore(&host->lock, flags);
513 mmc_schedule_delayed_work(&host->detect, delay);
516 EXPORT_SYMBOL(mmc_detect_change);
519 void mmc_rescan(struct work_struct *work)
521 struct mmc_host *host =
522 container_of(work, struct mmc_host, detect.work);
528 if (host->bus_ops == NULL) {
530 * Only we can add a new handler, so it's safe to
531 * release the lock here.
535 mmc_claim_host(host);
540 mmc_send_if_cond(host, host->ocr_avail);
542 err = mmc_send_app_op_cond(host, 0, &ocr);
543 if (err == MMC_ERR_NONE) {
544 if (mmc_attach_sd(host, ocr))
548 * If we fail to detect any SD cards then try
549 * searching for MMC cards.
551 err = mmc_send_op_cond(host, 0, &ocr);
552 if (err == MMC_ERR_NONE) {
553 if (mmc_attach_mmc(host, ocr))
557 mmc_release_host(host);
561 if (host->bus_ops->detect && !host->bus_dead)
562 host->bus_ops->detect(host);
568 void mmc_start_host(struct mmc_host *host)
571 mmc_detect_change(host, 0);
574 void mmc_stop_host(struct mmc_host *host)
576 #ifdef CONFIG_MMC_DEBUG
578 spin_lock_irqsave(&host->lock, flags);
580 spin_unlock_irqrestore(&host->lock, flags);
583 mmc_flush_scheduled_work();
586 if (host->bus_ops && !host->bus_dead) {
587 if (host->bus_ops->remove)
588 host->bus_ops->remove(host);
590 mmc_claim_host(host);
591 mmc_detach_bus(host);
592 mmc_release_host(host);
604 * mmc_suspend_host - suspend a host
606 * @state: suspend mode (PM_SUSPEND_xxx)
608 int mmc_suspend_host(struct mmc_host *host, pm_message_t state)
610 mmc_flush_scheduled_work();
613 if (host->bus_ops && !host->bus_dead) {
614 if (host->bus_ops->suspend)
615 host->bus_ops->suspend(host);
616 if (!host->bus_ops->resume) {
617 if (host->bus_ops->remove)
618 host->bus_ops->remove(host);
620 mmc_claim_host(host);
621 mmc_detach_bus(host);
622 mmc_release_host(host);
632 EXPORT_SYMBOL(mmc_suspend_host);
635 * mmc_resume_host - resume a previously suspended host
638 int mmc_resume_host(struct mmc_host *host)
641 if (host->bus_ops && !host->bus_dead) {
643 BUG_ON(!host->bus_ops->resume);
644 host->bus_ops->resume(host);
649 * We add a slight delay here so that resume can progress
652 mmc_detect_change(host, 1);
657 EXPORT_SYMBOL(mmc_resume_host);
661 static int __init mmc_init(void)
665 workqueue = create_singlethread_workqueue("kmmcd");
669 ret = mmc_register_bus();
671 ret = mmc_register_host_class();
673 mmc_unregister_bus();
678 static void __exit mmc_exit(void)
680 mmc_unregister_host_class();
681 mmc_unregister_bus();
682 destroy_workqueue(workqueue);
685 module_init(mmc_init);
686 module_exit(mmc_exit);
688 MODULE_LICENSE("GPL");