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) 2005-2008 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 <linux/leds.h>
22 #include <linux/scatterlist.h>
23 #include <linux/log2.h>
25 #include <linux/mmc/card.h>
26 #include <linux/mmc/host.h>
27 #include <linux/mmc/mmc.h>
28 #include <linux/mmc/sd.h>
39 static struct workqueue_struct *workqueue;
42 * Enabling software CRCs on the data blocks can be a significant (30%)
43 * performance cost, and for other reasons may not always be desired.
44 * So we allow it it to be disabled.
47 module_param(use_spi_crc, bool, 0);
50 * Internal function. Schedule delayed work in the MMC work queue.
52 static int mmc_schedule_delayed_work(struct delayed_work *work,
55 return queue_delayed_work(workqueue, work, delay);
59 * Internal function. Flush all scheduled work from the MMC work queue.
61 static void mmc_flush_scheduled_work(void)
63 flush_workqueue(workqueue);
67 * mmc_request_done - finish processing an MMC request
68 * @host: MMC host which completed request
69 * @mrq: MMC request which request
71 * MMC drivers should call this function when they have completed
72 * their processing of a request.
74 void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
76 struct mmc_command *cmd = mrq->cmd;
79 if (err && cmd->retries && mmc_host_is_spi(host)) {
80 if (cmd->resp[0] & R1_SPI_ILLEGAL_COMMAND)
84 if (err && cmd->retries) {
85 pr_debug("%s: req failed (CMD%u): %d, retrying...\n",
86 mmc_hostname(host), cmd->opcode, err);
90 host->ops->request(host, mrq);
92 led_trigger_event(host->led, LED_OFF);
94 pr_debug("%s: req done (CMD%u): %d: %08x %08x %08x %08x\n",
95 mmc_hostname(host), cmd->opcode, err,
96 cmd->resp[0], cmd->resp[1],
97 cmd->resp[2], cmd->resp[3]);
100 pr_debug("%s: %d bytes transferred: %d\n",
102 mrq->data->bytes_xfered, mrq->data->error);
106 pr_debug("%s: (CMD%u): %d: %08x %08x %08x %08x\n",
107 mmc_hostname(host), mrq->stop->opcode,
109 mrq->stop->resp[0], mrq->stop->resp[1],
110 mrq->stop->resp[2], mrq->stop->resp[3]);
118 EXPORT_SYMBOL(mmc_request_done);
121 mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
123 #ifdef CONFIG_MMC_DEBUG
125 struct scatterlist *sg;
128 pr_debug("%s: starting CMD%u arg %08x flags %08x\n",
129 mmc_hostname(host), mrq->cmd->opcode,
130 mrq->cmd->arg, mrq->cmd->flags);
133 pr_debug("%s: blksz %d blocks %d flags %08x "
134 "tsac %d ms nsac %d\n",
135 mmc_hostname(host), mrq->data->blksz,
136 mrq->data->blocks, mrq->data->flags,
137 mrq->data->timeout_ns / 1000000,
138 mrq->data->timeout_clks);
142 pr_debug("%s: CMD%u arg %08x flags %08x\n",
143 mmc_hostname(host), mrq->stop->opcode,
144 mrq->stop->arg, mrq->stop->flags);
147 WARN_ON(!host->claimed);
149 led_trigger_event(host->led, LED_FULL);
154 BUG_ON(mrq->data->blksz > host->max_blk_size);
155 BUG_ON(mrq->data->blocks > host->max_blk_count);
156 BUG_ON(mrq->data->blocks * mrq->data->blksz >
159 #ifdef CONFIG_MMC_DEBUG
161 for_each_sg(mrq->data->sg, sg, mrq->data->sg_len, i)
163 BUG_ON(sz != mrq->data->blocks * mrq->data->blksz);
166 mrq->cmd->data = mrq->data;
167 mrq->data->error = 0;
168 mrq->data->mrq = mrq;
170 mrq->data->stop = mrq->stop;
171 mrq->stop->error = 0;
172 mrq->stop->mrq = mrq;
175 host->ops->request(host, mrq);
178 static void mmc_wait_done(struct mmc_request *mrq)
180 complete(mrq->done_data);
184 * mmc_wait_for_req - start a request and wait for completion
185 * @host: MMC host to start command
186 * @mrq: MMC request to start
188 * Start a new MMC custom command request for a host, and wait
189 * for the command to complete. Does not attempt to parse the
192 void mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq)
194 DECLARE_COMPLETION_ONSTACK(complete);
196 mrq->done_data = &complete;
197 mrq->done = mmc_wait_done;
199 mmc_start_request(host, mrq);
201 wait_for_completion(&complete);
204 EXPORT_SYMBOL(mmc_wait_for_req);
207 * mmc_wait_for_cmd - start a command and wait for completion
208 * @host: MMC host to start command
209 * @cmd: MMC command to start
210 * @retries: maximum number of retries
212 * Start a new MMC command for a host, and wait for the command
213 * to complete. Return any error that occurred while the command
214 * was executing. Do not attempt to parse the response.
216 int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries)
218 struct mmc_request mrq;
220 WARN_ON(!host->claimed);
222 memset(&mrq, 0, sizeof(struct mmc_request));
224 memset(cmd->resp, 0, sizeof(cmd->resp));
225 cmd->retries = retries;
230 mmc_wait_for_req(host, &mrq);
235 EXPORT_SYMBOL(mmc_wait_for_cmd);
238 * mmc_set_data_timeout - set the timeout for a data command
239 * @data: data phase for command
240 * @card: the MMC card associated with the data transfer
242 * Computes the data timeout parameters according to the
243 * correct algorithm given the card type.
245 void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card)
250 * SDIO cards only define an upper 1 s limit on access.
252 if (mmc_card_sdio(card)) {
253 data->timeout_ns = 1000000000;
254 data->timeout_clks = 0;
259 * SD cards use a 100 multiplier rather than 10
261 mult = mmc_card_sd(card) ? 100 : 10;
264 * Scale up the multiplier (and therefore the timeout) by
265 * the r2w factor for writes.
267 if (data->flags & MMC_DATA_WRITE)
268 mult <<= card->csd.r2w_factor;
270 data->timeout_ns = card->csd.tacc_ns * mult;
271 data->timeout_clks = card->csd.tacc_clks * mult;
274 * SD cards also have an upper limit on the timeout.
276 if (mmc_card_sd(card)) {
277 unsigned int timeout_us, limit_us;
279 timeout_us = data->timeout_ns / 1000;
280 timeout_us += data->timeout_clks * 1000 /
281 (card->host->ios.clock / 1000);
283 if (data->flags & MMC_DATA_WRITE)
285 * The limit is really 250 ms, but that is
286 * insufficient for some crappy cards.
293 * SDHC cards always use these fixed values.
295 if (timeout_us > limit_us || mmc_card_blockaddr(card)) {
296 data->timeout_ns = limit_us * 1000;
297 data->timeout_clks = 0;
301 * Some cards need very high timeouts if driven in SPI mode.
302 * The worst observed timeout was 900ms after writing a
303 * continuous stream of data until the internal logic
306 if (mmc_host_is_spi(card->host)) {
307 if (data->flags & MMC_DATA_WRITE) {
308 if (data->timeout_ns < 1000000000)
309 data->timeout_ns = 1000000000; /* 1s */
311 if (data->timeout_ns < 100000000)
312 data->timeout_ns = 100000000; /* 100ms */
316 EXPORT_SYMBOL(mmc_set_data_timeout);
319 * mmc_align_data_size - pads a transfer size to a more optimal value
320 * @card: the MMC card associated with the data transfer
321 * @sz: original transfer size
323 * Pads the original data size with a number of extra bytes in
324 * order to avoid controller bugs and/or performance hits
325 * (e.g. some controllers revert to PIO for certain sizes).
327 * Returns the improved size, which might be unmodified.
329 * Note that this function is only relevant when issuing a
330 * single scatter gather entry.
332 unsigned int mmc_align_data_size(struct mmc_card *card, unsigned int sz)
335 * FIXME: We don't have a system for the controller to tell
336 * the core about its problems yet, so for now we just 32-bit
339 sz = ((sz + 3) / 4) * 4;
343 EXPORT_SYMBOL(mmc_align_data_size);
346 * __mmc_claim_host - exclusively claim a host
347 * @host: mmc host to claim
348 * @abort: whether or not the operation should be aborted
350 * Claim a host for a set of operations. If @abort is non null and
351 * dereference a non-zero value then this will return prematurely with
352 * that non-zero value without acquiring the lock. Returns zero
353 * with the lock held otherwise.
355 int __mmc_claim_host(struct mmc_host *host, atomic_t *abort)
357 DECLARE_WAITQUEUE(wait, current);
363 add_wait_queue(&host->wq, &wait);
364 spin_lock_irqsave(&host->lock, flags);
366 set_current_state(TASK_UNINTERRUPTIBLE);
367 stop = abort ? atomic_read(abort) : 0;
368 if (stop || !host->claimed)
370 spin_unlock_irqrestore(&host->lock, flags);
372 spin_lock_irqsave(&host->lock, flags);
374 set_current_state(TASK_RUNNING);
379 spin_unlock_irqrestore(&host->lock, flags);
380 remove_wait_queue(&host->wq, &wait);
384 EXPORT_SYMBOL(__mmc_claim_host);
387 * mmc_release_host - release a host
388 * @host: mmc host to release
390 * Release a MMC host, allowing others to claim the host
391 * for their operations.
393 void mmc_release_host(struct mmc_host *host)
397 WARN_ON(!host->claimed);
399 spin_lock_irqsave(&host->lock, flags);
401 spin_unlock_irqrestore(&host->lock, flags);
406 EXPORT_SYMBOL(mmc_release_host);
409 * Internal function that does the actual ios call to the host driver,
410 * optionally printing some debug output.
412 static inline void mmc_set_ios(struct mmc_host *host)
414 struct mmc_ios *ios = &host->ios;
416 pr_debug("%s: clock %uHz busmode %u powermode %u cs %u Vdd %u "
417 "width %u timing %u\n",
418 mmc_hostname(host), ios->clock, ios->bus_mode,
419 ios->power_mode, ios->chip_select, ios->vdd,
420 ios->bus_width, ios->timing);
422 host->ops->set_ios(host, ios);
426 * Control chip select pin on a host.
428 void mmc_set_chip_select(struct mmc_host *host, int mode)
430 host->ios.chip_select = mode;
435 * Sets the host clock to the highest possible frequency that
438 void mmc_set_clock(struct mmc_host *host, unsigned int hz)
440 WARN_ON(hz < host->f_min);
442 if (hz > host->f_max)
445 host->ios.clock = hz;
450 * Change the bus mode (open drain/push-pull) of a host.
452 void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode)
454 host->ios.bus_mode = mode;
459 * Change data bus width of a host.
461 void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
463 host->ios.bus_width = width;
468 * mmc_vdd_to_ocrbitnum - Convert a voltage to the OCR bit number
470 * @low_bits: prefer low bits in boundary cases
472 * This function returns the OCR bit number according to the provided @vdd
473 * value. If conversion is not possible a negative errno value returned.
475 * Depending on the @low_bits flag the function prefers low or high OCR bits
476 * on boundary voltages. For example,
477 * with @low_bits = true, 3300 mV translates to ilog2(MMC_VDD_32_33);
478 * with @low_bits = false, 3300 mV translates to ilog2(MMC_VDD_33_34);
480 * Any value in the [1951:1999] range translates to the ilog2(MMC_VDD_20_21).
482 static int mmc_vdd_to_ocrbitnum(int vdd, bool low_bits)
484 const int max_bit = ilog2(MMC_VDD_35_36);
487 if (vdd < 1650 || vdd > 3600)
490 if (vdd >= 1650 && vdd <= 1950)
491 return ilog2(MMC_VDD_165_195);
496 /* Base 2000 mV, step 100 mV, bit's base 8. */
497 bit = (vdd - 2000) / 100 + 8;
504 * mmc_vddrange_to_ocrmask - Convert a voltage range to the OCR mask
505 * @vdd_min: minimum voltage value (mV)
506 * @vdd_max: maximum voltage value (mV)
508 * This function returns the OCR mask bits according to the provided @vdd_min
509 * and @vdd_max values. If conversion is not possible the function returns 0.
511 * Notes wrt boundary cases:
512 * This function sets the OCR bits for all boundary voltages, for example
513 * [3300:3400] range is translated to MMC_VDD_32_33 | MMC_VDD_33_34 |
514 * MMC_VDD_34_35 mask.
516 u32 mmc_vddrange_to_ocrmask(int vdd_min, int vdd_max)
520 if (vdd_max < vdd_min)
523 /* Prefer high bits for the boundary vdd_max values. */
524 vdd_max = mmc_vdd_to_ocrbitnum(vdd_max, false);
528 /* Prefer low bits for the boundary vdd_min values. */
529 vdd_min = mmc_vdd_to_ocrbitnum(vdd_min, true);
533 /* Fill the mask, from max bit to min bit. */
534 while (vdd_max >= vdd_min)
535 mask |= 1 << vdd_max--;
539 EXPORT_SYMBOL(mmc_vddrange_to_ocrmask);
542 * Mask off any voltages we don't support and select
545 u32 mmc_select_voltage(struct mmc_host *host, u32 ocr)
549 ocr &= host->ocr_avail;
560 pr_warning("%s: host doesn't support card's voltages\n",
569 * Select timing parameters for host.
571 void mmc_set_timing(struct mmc_host *host, unsigned int timing)
573 host->ios.timing = timing;
578 * Apply power to the MMC stack. This is a two-stage process.
579 * First, we enable power to the card without the clock running.
580 * We then wait a bit for the power to stabilise. Finally,
581 * enable the bus drivers and clock to the card.
583 * We must _NOT_ enable the clock prior to power stablising.
585 * If a host does all the power sequencing itself, ignore the
586 * initial MMC_POWER_UP stage.
588 static void mmc_power_up(struct mmc_host *host)
590 int bit = fls(host->ocr_avail) - 1;
593 if (mmc_host_is_spi(host)) {
594 host->ios.chip_select = MMC_CS_HIGH;
595 host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
597 host->ios.chip_select = MMC_CS_DONTCARE;
598 host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
600 host->ios.power_mode = MMC_POWER_UP;
601 host->ios.bus_width = MMC_BUS_WIDTH_1;
602 host->ios.timing = MMC_TIMING_LEGACY;
606 * This delay should be sufficient to allow the power supply
607 * to reach the minimum voltage.
611 host->ios.clock = host->f_min;
612 host->ios.power_mode = MMC_POWER_ON;
616 * This delay must be at least 74 clock sizes, or 1 ms, or the
617 * time required to reach a stable voltage.
622 static void mmc_power_off(struct mmc_host *host)
626 if (!mmc_host_is_spi(host)) {
627 host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
628 host->ios.chip_select = MMC_CS_DONTCARE;
630 host->ios.power_mode = MMC_POWER_OFF;
631 host->ios.bus_width = MMC_BUS_WIDTH_1;
632 host->ios.timing = MMC_TIMING_LEGACY;
637 * Cleanup when the last reference to the bus operator is dropped.
639 static void __mmc_release_bus(struct mmc_host *host)
642 BUG_ON(host->bus_refs);
643 BUG_ON(!host->bus_dead);
645 host->bus_ops = NULL;
649 * Increase reference count of bus operator
651 static inline void mmc_bus_get(struct mmc_host *host)
655 spin_lock_irqsave(&host->lock, flags);
657 spin_unlock_irqrestore(&host->lock, flags);
661 * Decrease reference count of bus operator and free it if
662 * it is the last reference.
664 static inline void mmc_bus_put(struct mmc_host *host)
668 spin_lock_irqsave(&host->lock, flags);
670 if ((host->bus_refs == 0) && host->bus_ops)
671 __mmc_release_bus(host);
672 spin_unlock_irqrestore(&host->lock, flags);
676 * Assign a mmc bus handler to a host. Only one bus handler may control a
677 * host at any given time.
679 void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops)
686 WARN_ON(!host->claimed);
688 spin_lock_irqsave(&host->lock, flags);
690 BUG_ON(host->bus_ops);
691 BUG_ON(host->bus_refs);
697 spin_unlock_irqrestore(&host->lock, flags);
701 * Remove the current bus handler from a host. Assumes that there are
702 * no interesting cards left, so the bus is powered down.
704 void mmc_detach_bus(struct mmc_host *host)
710 WARN_ON(!host->claimed);
711 WARN_ON(!host->bus_ops);
713 spin_lock_irqsave(&host->lock, flags);
717 spin_unlock_irqrestore(&host->lock, flags);
725 * mmc_detect_change - process change of state on a MMC socket
726 * @host: host which changed state.
727 * @delay: optional delay to wait before detection (jiffies)
729 * MMC drivers should call this when they detect a card has been
730 * inserted or removed. The MMC layer will confirm that any
731 * present card is still functional, and initialize any newly
734 void mmc_detect_change(struct mmc_host *host, unsigned long delay)
736 #ifdef CONFIG_MMC_DEBUG
738 spin_lock_irqsave(&host->lock, flags);
739 WARN_ON(host->removed);
740 spin_unlock_irqrestore(&host->lock, flags);
743 mmc_schedule_delayed_work(&host->detect, delay);
746 EXPORT_SYMBOL(mmc_detect_change);
749 void mmc_rescan(struct work_struct *work)
751 struct mmc_host *host =
752 container_of(work, struct mmc_host, detect.work);
758 if (host->bus_ops == NULL) {
760 * Only we can add a new handler, so it's safe to
761 * release the lock here.
765 if (host->ops->get_cd && host->ops->get_cd(host) == 0)
768 mmc_claim_host(host);
773 mmc_send_if_cond(host, host->ocr_avail);
776 * First we search for SDIO...
778 err = mmc_send_io_op_cond(host, 0, &ocr);
780 if (mmc_attach_sdio(host, ocr))
786 * ...then normal SD...
788 err = mmc_send_app_op_cond(host, 0, &ocr);
790 if (mmc_attach_sd(host, ocr))
796 * ...and finally MMC.
798 err = mmc_send_op_cond(host, 0, &ocr);
800 if (mmc_attach_mmc(host, ocr))
805 mmc_release_host(host);
808 if (host->bus_ops->detect && !host->bus_dead)
809 host->bus_ops->detect(host);
814 if (host->caps & MMC_CAP_NEEDS_POLL)
815 mmc_schedule_delayed_work(&host->detect, HZ);
818 void mmc_start_host(struct mmc_host *host)
821 mmc_detect_change(host, 0);
824 void mmc_stop_host(struct mmc_host *host)
826 #ifdef CONFIG_MMC_DEBUG
828 spin_lock_irqsave(&host->lock, flags);
830 spin_unlock_irqrestore(&host->lock, flags);
833 cancel_delayed_work(&host->detect);
834 mmc_flush_scheduled_work();
837 if (host->bus_ops && !host->bus_dead) {
838 if (host->bus_ops->remove)
839 host->bus_ops->remove(host);
841 mmc_claim_host(host);
842 mmc_detach_bus(host);
843 mmc_release_host(host);
855 * mmc_suspend_host - suspend a host
857 * @state: suspend mode (PM_SUSPEND_xxx)
859 int mmc_suspend_host(struct mmc_host *host, pm_message_t state)
861 cancel_delayed_work(&host->detect);
862 mmc_flush_scheduled_work();
865 if (host->bus_ops && !host->bus_dead) {
866 if (host->bus_ops->suspend)
867 host->bus_ops->suspend(host);
868 if (!host->bus_ops->resume) {
869 if (host->bus_ops->remove)
870 host->bus_ops->remove(host);
872 mmc_claim_host(host);
873 mmc_detach_bus(host);
874 mmc_release_host(host);
884 EXPORT_SYMBOL(mmc_suspend_host);
887 * mmc_resume_host - resume a previously suspended host
890 int mmc_resume_host(struct mmc_host *host)
893 if (host->bus_ops && !host->bus_dead) {
895 mmc_select_voltage(host, host->ocr);
896 BUG_ON(!host->bus_ops->resume);
897 host->bus_ops->resume(host);
902 * We add a slight delay here so that resume can progress
905 mmc_detect_change(host, 1);
910 EXPORT_SYMBOL(mmc_resume_host);
914 static int __init mmc_init(void)
918 workqueue = create_singlethread_workqueue("kmmcd");
922 ret = mmc_register_bus();
924 goto destroy_workqueue;
926 ret = mmc_register_host_class();
930 ret = sdio_register_bus();
932 goto unregister_host_class;
936 unregister_host_class:
937 mmc_unregister_host_class();
939 mmc_unregister_bus();
941 destroy_workqueue(workqueue);
946 static void __exit mmc_exit(void)
948 sdio_unregister_bus();
949 mmc_unregister_host_class();
950 mmc_unregister_bus();
951 destroy_workqueue(workqueue);
954 subsys_initcall(mmc_init);
955 module_exit(mmc_exit);
957 MODULE_LICENSE("GPL");