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>
24 #include <linux/regulator/consumer.h>
25 #include <linux/pm_runtime.h>
26 #include <linux/pm_wakeup.h>
27 #include <linux/suspend.h>
28 #include <linux/fault-inject.h>
29 #include <linux/random.h>
30 #include <linux/slab.h>
33 #include <linux/mmc/card.h>
34 #include <linux/mmc/host.h>
35 #include <linux/mmc/mmc.h>
36 #include <linux/mmc/sd.h>
37 #include <linux/mmc/slot-gpio.h>
49 /* If the device is not responding */
50 #define MMC_CORE_TIMEOUT_MS (10 * 60 * 1000) /* 10 minute timeout */
53 * Background operations can take a long time, depending on the housekeeping
54 * operations the card has to perform.
56 #define MMC_BKOPS_MAX_TIMEOUT (4 * 60 * 1000) /* max time to wait in ms */
58 static struct workqueue_struct *workqueue;
59 static const unsigned freqs[] = { 400000, 300000, 200000, 100000 };
62 * Enabling software CRCs on the data blocks can be a significant (30%)
63 * performance cost, and for other reasons may not always be desired.
64 * So we allow it it to be disabled.
67 module_param(use_spi_crc, bool, 0);
70 * Internal function. Schedule delayed work in the MMC work queue.
72 static int mmc_schedule_delayed_work(struct delayed_work *work,
75 return queue_delayed_work(workqueue, work, delay);
79 * Internal function. Flush all scheduled work from the MMC work queue.
81 static void mmc_flush_scheduled_work(void)
83 flush_workqueue(workqueue);
86 #ifdef CONFIG_FAIL_MMC_REQUEST
89 * Internal function. Inject random data errors.
90 * If mmc_data is NULL no errors are injected.
92 static void mmc_should_fail_request(struct mmc_host *host,
93 struct mmc_request *mrq)
95 struct mmc_command *cmd = mrq->cmd;
96 struct mmc_data *data = mrq->data;
97 static const int data_errors[] = {
106 if (cmd->error || data->error ||
107 !should_fail(&host->fail_mmc_request, data->blksz * data->blocks))
110 data->error = data_errors[prandom_u32() % ARRAY_SIZE(data_errors)];
111 data->bytes_xfered = (prandom_u32() % (data->bytes_xfered >> 9)) << 9;
114 #else /* CONFIG_FAIL_MMC_REQUEST */
116 static inline void mmc_should_fail_request(struct mmc_host *host,
117 struct mmc_request *mrq)
121 #endif /* CONFIG_FAIL_MMC_REQUEST */
124 * mmc_request_done - finish processing an MMC request
125 * @host: MMC host which completed request
126 * @mrq: MMC request which request
128 * MMC drivers should call this function when they have completed
129 * their processing of a request.
131 void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
133 struct mmc_command *cmd = mrq->cmd;
134 int err = cmd->error;
136 /* Flag re-tuning needed on CRC errors */
137 if (err == -EILSEQ || (mrq->sbc && mrq->sbc->error == -EILSEQ) ||
138 (mrq->data && mrq->data->error == -EILSEQ) ||
139 (mrq->stop && mrq->stop->error == -EILSEQ))
140 mmc_retune_needed(host);
142 if (err && cmd->retries && mmc_host_is_spi(host)) {
143 if (cmd->resp[0] & R1_SPI_ILLEGAL_COMMAND)
147 if (err && cmd->retries && !mmc_card_removed(host->card)) {
149 * Request starter must handle retries - see
150 * mmc_wait_for_req_done().
155 mmc_should_fail_request(host, mrq);
157 led_trigger_event(host->led, LED_OFF);
160 pr_debug("%s: req done <CMD%u>: %d: %08x %08x %08x %08x\n",
161 mmc_hostname(host), mrq->sbc->opcode,
163 mrq->sbc->resp[0], mrq->sbc->resp[1],
164 mrq->sbc->resp[2], mrq->sbc->resp[3]);
167 pr_debug("%s: req done (CMD%u): %d: %08x %08x %08x %08x\n",
168 mmc_hostname(host), cmd->opcode, err,
169 cmd->resp[0], cmd->resp[1],
170 cmd->resp[2], cmd->resp[3]);
173 pr_debug("%s: %d bytes transferred: %d\n",
175 mrq->data->bytes_xfered, mrq->data->error);
179 pr_debug("%s: (CMD%u): %d: %08x %08x %08x %08x\n",
180 mmc_hostname(host), mrq->stop->opcode,
182 mrq->stop->resp[0], mrq->stop->resp[1],
183 mrq->stop->resp[2], mrq->stop->resp[3]);
189 mmc_host_clk_release(host);
193 EXPORT_SYMBOL(mmc_request_done);
195 static void __mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
199 /* Assumes host controller has been runtime resumed by mmc_claim_host */
200 err = mmc_retune(host);
202 mrq->cmd->error = err;
203 mmc_request_done(host, mrq);
207 host->ops->request(host, mrq);
210 static int mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
212 #ifdef CONFIG_MMC_DEBUG
214 struct scatterlist *sg;
216 mmc_retune_hold(host);
218 if (mmc_card_removed(host->card))
222 pr_debug("<%s: starting CMD%u arg %08x flags %08x>\n",
223 mmc_hostname(host), mrq->sbc->opcode,
224 mrq->sbc->arg, mrq->sbc->flags);
227 pr_debug("%s: starting CMD%u arg %08x flags %08x\n",
228 mmc_hostname(host), mrq->cmd->opcode,
229 mrq->cmd->arg, mrq->cmd->flags);
232 pr_debug("%s: blksz %d blocks %d flags %08x "
233 "tsac %d ms nsac %d\n",
234 mmc_hostname(host), mrq->data->blksz,
235 mrq->data->blocks, mrq->data->flags,
236 mrq->data->timeout_ns / 1000000,
237 mrq->data->timeout_clks);
241 pr_debug("%s: CMD%u arg %08x flags %08x\n",
242 mmc_hostname(host), mrq->stop->opcode,
243 mrq->stop->arg, mrq->stop->flags);
246 WARN_ON(!host->claimed);
255 BUG_ON(mrq->data->blksz > host->max_blk_size);
256 BUG_ON(mrq->data->blocks > host->max_blk_count);
257 BUG_ON(mrq->data->blocks * mrq->data->blksz >
260 #ifdef CONFIG_MMC_DEBUG
262 for_each_sg(mrq->data->sg, sg, mrq->data->sg_len, i)
264 BUG_ON(sz != mrq->data->blocks * mrq->data->blksz);
267 mrq->cmd->data = mrq->data;
268 mrq->data->error = 0;
269 mrq->data->mrq = mrq;
271 mrq->data->stop = mrq->stop;
272 mrq->stop->error = 0;
273 mrq->stop->mrq = mrq;
276 mmc_host_clk_hold(host);
277 led_trigger_event(host->led, LED_FULL);
278 __mmc_start_request(host, mrq);
284 * mmc_start_bkops - start BKOPS for supported cards
285 * @card: MMC card to start BKOPS
286 * @form_exception: A flag to indicate if this function was
287 * called due to an exception raised by the card
289 * Start background operations whenever requested.
290 * When the urgent BKOPS bit is set in a R1 command response
291 * then background operations should be started immediately.
293 void mmc_start_bkops(struct mmc_card *card, bool from_exception)
297 bool use_busy_signal;
301 if (!card->ext_csd.man_bkops_en || mmc_card_doing_bkops(card))
304 err = mmc_read_bkops_status(card);
306 pr_err("%s: Failed to read bkops status: %d\n",
307 mmc_hostname(card->host), err);
311 if (!card->ext_csd.raw_bkops_status)
314 if (card->ext_csd.raw_bkops_status < EXT_CSD_BKOPS_LEVEL_2 &&
318 mmc_claim_host(card->host);
319 if (card->ext_csd.raw_bkops_status >= EXT_CSD_BKOPS_LEVEL_2) {
320 timeout = MMC_BKOPS_MAX_TIMEOUT;
321 use_busy_signal = true;
324 use_busy_signal = false;
327 mmc_retune_hold(card->host);
329 err = __mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
330 EXT_CSD_BKOPS_START, 1, timeout,
331 use_busy_signal, true, false);
333 pr_warn("%s: Error %d starting bkops\n",
334 mmc_hostname(card->host), err);
335 mmc_retune_release(card->host);
340 * For urgent bkops status (LEVEL_2 and more)
341 * bkops executed synchronously, otherwise
342 * the operation is in progress
344 if (!use_busy_signal)
345 mmc_card_set_doing_bkops(card);
347 mmc_retune_release(card->host);
349 mmc_release_host(card->host);
351 EXPORT_SYMBOL(mmc_start_bkops);
354 * mmc_wait_data_done() - done callback for data request
355 * @mrq: done data request
357 * Wakes up mmc context, passed as a callback to host controller driver
359 static void mmc_wait_data_done(struct mmc_request *mrq)
361 mrq->host->context_info.is_done_rcv = true;
362 wake_up_interruptible(&mrq->host->context_info.wait);
365 static void mmc_wait_done(struct mmc_request *mrq)
367 complete(&mrq->completion);
371 *__mmc_start_data_req() - starts data request
372 * @host: MMC host to start the request
373 * @mrq: data request to start
375 * Sets the done callback to be called when request is completed by the card.
376 * Starts data mmc request execution
378 static int __mmc_start_data_req(struct mmc_host *host, struct mmc_request *mrq)
382 mrq->done = mmc_wait_data_done;
385 err = mmc_start_request(host, mrq);
387 mrq->cmd->error = err;
388 mmc_wait_data_done(mrq);
394 static int __mmc_start_req(struct mmc_host *host, struct mmc_request *mrq)
398 init_completion(&mrq->completion);
399 mrq->done = mmc_wait_done;
401 err = mmc_start_request(host, mrq);
403 mrq->cmd->error = err;
404 complete(&mrq->completion);
411 * mmc_wait_for_data_req_done() - wait for request completed
412 * @host: MMC host to prepare the command.
413 * @mrq: MMC request to wait for
415 * Blocks MMC context till host controller will ack end of data request
416 * execution or new request notification arrives from the block layer.
417 * Handles command retries.
419 * Returns enum mmc_blk_status after checking errors.
421 static int mmc_wait_for_data_req_done(struct mmc_host *host,
422 struct mmc_request *mrq,
423 struct mmc_async_req *next_req)
425 struct mmc_command *cmd;
426 struct mmc_context_info *context_info = &host->context_info;
431 wait_event_interruptible(context_info->wait,
432 (context_info->is_done_rcv ||
433 context_info->is_new_req));
434 spin_lock_irqsave(&context_info->lock, flags);
435 context_info->is_waiting_last_req = false;
436 spin_unlock_irqrestore(&context_info->lock, flags);
437 if (context_info->is_done_rcv) {
438 context_info->is_done_rcv = false;
439 context_info->is_new_req = false;
442 if (!cmd->error || !cmd->retries ||
443 mmc_card_removed(host->card)) {
444 err = host->areq->err_check(host->card,
446 break; /* return err */
448 mmc_retune_recheck(host);
449 pr_info("%s: req failed (CMD%u): %d, retrying...\n",
451 cmd->opcode, cmd->error);
454 __mmc_start_request(host, mrq);
455 continue; /* wait for done/new event again */
457 } else if (context_info->is_new_req) {
458 context_info->is_new_req = false;
460 return MMC_BLK_NEW_REQUEST;
463 mmc_retune_release(host);
467 static void mmc_wait_for_req_done(struct mmc_host *host,
468 struct mmc_request *mrq)
470 struct mmc_command *cmd;
473 wait_for_completion(&mrq->completion);
478 * If host has timed out waiting for the sanitize
479 * to complete, card might be still in programming state
480 * so let's try to bring the card out of programming
483 if (cmd->sanitize_busy && cmd->error == -ETIMEDOUT) {
484 if (!mmc_interrupt_hpi(host->card)) {
485 pr_warn("%s: %s: Interrupted sanitize\n",
486 mmc_hostname(host), __func__);
490 pr_err("%s: %s: Failed to interrupt sanitize\n",
491 mmc_hostname(host), __func__);
494 if (!cmd->error || !cmd->retries ||
495 mmc_card_removed(host->card))
498 mmc_retune_recheck(host);
500 pr_debug("%s: req failed (CMD%u): %d, retrying...\n",
501 mmc_hostname(host), cmd->opcode, cmd->error);
504 __mmc_start_request(host, mrq);
507 mmc_retune_release(host);
511 * mmc_pre_req - Prepare for a new request
512 * @host: MMC host to prepare command
513 * @mrq: MMC request to prepare for
514 * @is_first_req: true if there is no previous started request
515 * that may run in parellel to this call, otherwise false
517 * mmc_pre_req() is called in prior to mmc_start_req() to let
518 * host prepare for the new request. Preparation of a request may be
519 * performed while another request is running on the host.
521 static void mmc_pre_req(struct mmc_host *host, struct mmc_request *mrq,
524 if (host->ops->pre_req) {
525 mmc_host_clk_hold(host);
526 host->ops->pre_req(host, mrq, is_first_req);
527 mmc_host_clk_release(host);
532 * mmc_post_req - Post process a completed request
533 * @host: MMC host to post process command
534 * @mrq: MMC request to post process for
535 * @err: Error, if non zero, clean up any resources made in pre_req
537 * Let the host post process a completed request. Post processing of
538 * a request may be performed while another reuqest is running.
540 static void mmc_post_req(struct mmc_host *host, struct mmc_request *mrq,
543 if (host->ops->post_req) {
544 mmc_host_clk_hold(host);
545 host->ops->post_req(host, mrq, err);
546 mmc_host_clk_release(host);
551 * mmc_start_req - start a non-blocking request
552 * @host: MMC host to start command
553 * @areq: async request to start
554 * @error: out parameter returns 0 for success, otherwise non zero
556 * Start a new MMC custom command request for a host.
557 * If there is on ongoing async request wait for completion
558 * of that request and start the new one and return.
559 * Does not wait for the new request to complete.
561 * Returns the completed request, NULL in case of none completed.
562 * Wait for the an ongoing request (previoulsy started) to complete and
563 * return the completed request. If there is no ongoing request, NULL
564 * is returned without waiting. NULL is not an error condition.
566 struct mmc_async_req *mmc_start_req(struct mmc_host *host,
567 struct mmc_async_req *areq, int *error)
571 struct mmc_async_req *data = host->areq;
573 /* Prepare a new request */
575 mmc_pre_req(host, areq->mrq, !host->areq);
578 err = mmc_wait_for_data_req_done(host, host->areq->mrq, areq);
579 if (err == MMC_BLK_NEW_REQUEST) {
583 * The previous request was not completed,
589 * Check BKOPS urgency for each R1 response
591 if (host->card && mmc_card_mmc(host->card) &&
592 ((mmc_resp_type(host->areq->mrq->cmd) == MMC_RSP_R1) ||
593 (mmc_resp_type(host->areq->mrq->cmd) == MMC_RSP_R1B)) &&
594 (host->areq->mrq->cmd->resp[0] & R1_EXCEPTION_EVENT)) {
596 /* Cancel the prepared request */
598 mmc_post_req(host, areq->mrq, -EINVAL);
600 mmc_start_bkops(host->card, true);
602 /* prepare the request again */
604 mmc_pre_req(host, areq->mrq, !host->areq);
609 start_err = __mmc_start_data_req(host, areq->mrq);
612 mmc_post_req(host, host->areq->mrq, 0);
614 /* Cancel a prepared request if it was not started. */
615 if ((err || start_err) && areq)
616 mmc_post_req(host, areq->mrq, -EINVAL);
627 EXPORT_SYMBOL(mmc_start_req);
630 * mmc_wait_for_req - start a request and wait for completion
631 * @host: MMC host to start command
632 * @mrq: MMC request to start
634 * Start a new MMC custom command request for a host, and wait
635 * for the command to complete. Does not attempt to parse the
638 void mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq)
640 __mmc_start_req(host, mrq);
641 mmc_wait_for_req_done(host, mrq);
643 EXPORT_SYMBOL(mmc_wait_for_req);
646 * mmc_interrupt_hpi - Issue for High priority Interrupt
647 * @card: the MMC card associated with the HPI transfer
649 * Issued High Priority Interrupt, and check for card status
650 * until out-of prg-state.
652 int mmc_interrupt_hpi(struct mmc_card *card)
656 unsigned long prg_wait;
660 if (!card->ext_csd.hpi_en) {
661 pr_info("%s: HPI enable bit unset\n", mmc_hostname(card->host));
665 mmc_claim_host(card->host);
666 err = mmc_send_status(card, &status);
668 pr_err("%s: Get card status fail\n", mmc_hostname(card->host));
672 switch (R1_CURRENT_STATE(status)) {
678 * In idle and transfer states, HPI is not needed and the caller
679 * can issue the next intended command immediately
685 /* In all other states, it's illegal to issue HPI */
686 pr_debug("%s: HPI cannot be sent. Card state=%d\n",
687 mmc_hostname(card->host), R1_CURRENT_STATE(status));
692 err = mmc_send_hpi_cmd(card, &status);
696 prg_wait = jiffies + msecs_to_jiffies(card->ext_csd.out_of_int_time);
698 err = mmc_send_status(card, &status);
700 if (!err && R1_CURRENT_STATE(status) == R1_STATE_TRAN)
702 if (time_after(jiffies, prg_wait))
707 mmc_release_host(card->host);
710 EXPORT_SYMBOL(mmc_interrupt_hpi);
713 * mmc_wait_for_cmd - start a command and wait for completion
714 * @host: MMC host to start command
715 * @cmd: MMC command to start
716 * @retries: maximum number of retries
718 * Start a new MMC command for a host, and wait for the command
719 * to complete. Return any error that occurred while the command
720 * was executing. Do not attempt to parse the response.
722 int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries)
724 struct mmc_request mrq = {NULL};
726 WARN_ON(!host->claimed);
728 memset(cmd->resp, 0, sizeof(cmd->resp));
729 cmd->retries = retries;
734 mmc_wait_for_req(host, &mrq);
739 EXPORT_SYMBOL(mmc_wait_for_cmd);
742 * mmc_stop_bkops - stop ongoing BKOPS
743 * @card: MMC card to check BKOPS
745 * Send HPI command to stop ongoing background operations to
746 * allow rapid servicing of foreground operations, e.g. read/
747 * writes. Wait until the card comes out of the programming state
748 * to avoid errors in servicing read/write requests.
750 int mmc_stop_bkops(struct mmc_card *card)
755 err = mmc_interrupt_hpi(card);
758 * If err is EINVAL, we can't issue an HPI.
759 * It should complete the BKOPS.
761 if (!err || (err == -EINVAL)) {
762 mmc_card_clr_doing_bkops(card);
763 mmc_retune_release(card->host);
769 EXPORT_SYMBOL(mmc_stop_bkops);
771 int mmc_read_bkops_status(struct mmc_card *card)
776 mmc_claim_host(card->host);
777 err = mmc_get_ext_csd(card, &ext_csd);
778 mmc_release_host(card->host);
782 card->ext_csd.raw_bkops_status = ext_csd[EXT_CSD_BKOPS_STATUS];
783 card->ext_csd.raw_exception_status = ext_csd[EXT_CSD_EXP_EVENTS_STATUS];
787 EXPORT_SYMBOL(mmc_read_bkops_status);
790 * mmc_set_data_timeout - set the timeout for a data command
791 * @data: data phase for command
792 * @card: the MMC card associated with the data transfer
794 * Computes the data timeout parameters according to the
795 * correct algorithm given the card type.
797 void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card)
802 * SDIO cards only define an upper 1 s limit on access.
804 if (mmc_card_sdio(card)) {
805 data->timeout_ns = 1000000000;
806 data->timeout_clks = 0;
811 * SD cards use a 100 multiplier rather than 10
813 mult = mmc_card_sd(card) ? 100 : 10;
816 * Scale up the multiplier (and therefore the timeout) by
817 * the r2w factor for writes.
819 if (data->flags & MMC_DATA_WRITE)
820 mult <<= card->csd.r2w_factor;
822 data->timeout_ns = card->csd.tacc_ns * mult;
823 data->timeout_clks = card->csd.tacc_clks * mult;
826 * SD cards also have an upper limit on the timeout.
828 if (mmc_card_sd(card)) {
829 unsigned int timeout_us, limit_us;
831 timeout_us = data->timeout_ns / 1000;
832 if (mmc_host_clk_rate(card->host))
833 timeout_us += data->timeout_clks * 1000 /
834 (mmc_host_clk_rate(card->host) / 1000);
836 if (data->flags & MMC_DATA_WRITE)
838 * The MMC spec "It is strongly recommended
839 * for hosts to implement more than 500ms
840 * timeout value even if the card indicates
841 * the 250ms maximum busy length." Even the
842 * previous value of 300ms is known to be
843 * insufficient for some cards.
850 * SDHC cards always use these fixed values.
852 if (timeout_us > limit_us || mmc_card_blockaddr(card)) {
853 data->timeout_ns = limit_us * 1000;
854 data->timeout_clks = 0;
857 /* assign limit value if invalid */
859 data->timeout_ns = limit_us * 1000;
863 * Some cards require longer data read timeout than indicated in CSD.
864 * Address this by setting the read timeout to a "reasonably high"
865 * value. For the cards tested, 300ms has proven enough. If necessary,
866 * this value can be increased if other problematic cards require this.
868 if (mmc_card_long_read_time(card) && data->flags & MMC_DATA_READ) {
869 data->timeout_ns = 300000000;
870 data->timeout_clks = 0;
874 * Some cards need very high timeouts if driven in SPI mode.
875 * The worst observed timeout was 900ms after writing a
876 * continuous stream of data until the internal logic
879 if (mmc_host_is_spi(card->host)) {
880 if (data->flags & MMC_DATA_WRITE) {
881 if (data->timeout_ns < 1000000000)
882 data->timeout_ns = 1000000000; /* 1s */
884 if (data->timeout_ns < 100000000)
885 data->timeout_ns = 100000000; /* 100ms */
889 EXPORT_SYMBOL(mmc_set_data_timeout);
892 * mmc_align_data_size - pads a transfer size to a more optimal value
893 * @card: the MMC card associated with the data transfer
894 * @sz: original transfer size
896 * Pads the original data size with a number of extra bytes in
897 * order to avoid controller bugs and/or performance hits
898 * (e.g. some controllers revert to PIO for certain sizes).
900 * Returns the improved size, which might be unmodified.
902 * Note that this function is only relevant when issuing a
903 * single scatter gather entry.
905 unsigned int mmc_align_data_size(struct mmc_card *card, unsigned int sz)
908 * FIXME: We don't have a system for the controller to tell
909 * the core about its problems yet, so for now we just 32-bit
912 sz = ((sz + 3) / 4) * 4;
916 EXPORT_SYMBOL(mmc_align_data_size);
919 * __mmc_claim_host - exclusively claim a host
920 * @host: mmc host to claim
921 * @abort: whether or not the operation should be aborted
923 * Claim a host for a set of operations. If @abort is non null and
924 * dereference a non-zero value then this will return prematurely with
925 * that non-zero value without acquiring the lock. Returns zero
926 * with the lock held otherwise.
928 int __mmc_claim_host(struct mmc_host *host, atomic_t *abort)
930 DECLARE_WAITQUEUE(wait, current);
937 add_wait_queue(&host->wq, &wait);
938 spin_lock_irqsave(&host->lock, flags);
940 set_current_state(TASK_UNINTERRUPTIBLE);
941 stop = abort ? atomic_read(abort) : 0;
942 if (stop || !host->claimed || host->claimer == current)
944 spin_unlock_irqrestore(&host->lock, flags);
946 spin_lock_irqsave(&host->lock, flags);
948 set_current_state(TASK_RUNNING);
951 host->claimer = current;
952 host->claim_cnt += 1;
953 if (host->claim_cnt == 1)
957 spin_unlock_irqrestore(&host->lock, flags);
958 remove_wait_queue(&host->wq, &wait);
961 pm_runtime_get_sync(mmc_dev(host));
965 EXPORT_SYMBOL(__mmc_claim_host);
968 * mmc_release_host - release a host
969 * @host: mmc host to release
971 * Release a MMC host, allowing others to claim the host
972 * for their operations.
974 void mmc_release_host(struct mmc_host *host)
978 WARN_ON(!host->claimed);
980 spin_lock_irqsave(&host->lock, flags);
981 if (--host->claim_cnt) {
982 /* Release for nested claim */
983 spin_unlock_irqrestore(&host->lock, flags);
986 host->claimer = NULL;
987 spin_unlock_irqrestore(&host->lock, flags);
989 pm_runtime_mark_last_busy(mmc_dev(host));
990 pm_runtime_put_autosuspend(mmc_dev(host));
993 EXPORT_SYMBOL(mmc_release_host);
996 * This is a helper function, which fetches a runtime pm reference for the
997 * card device and also claims the host.
999 void mmc_get_card(struct mmc_card *card)
1001 pm_runtime_get_sync(&card->dev);
1002 mmc_claim_host(card->host);
1004 EXPORT_SYMBOL(mmc_get_card);
1007 * This is a helper function, which releases the host and drops the runtime
1008 * pm reference for the card device.
1010 void mmc_put_card(struct mmc_card *card)
1012 mmc_release_host(card->host);
1013 pm_runtime_mark_last_busy(&card->dev);
1014 pm_runtime_put_autosuspend(&card->dev);
1016 EXPORT_SYMBOL(mmc_put_card);
1019 * Internal function that does the actual ios call to the host driver,
1020 * optionally printing some debug output.
1022 static inline void mmc_set_ios(struct mmc_host *host)
1024 struct mmc_ios *ios = &host->ios;
1026 pr_debug("%s: clock %uHz busmode %u powermode %u cs %u Vdd %u "
1027 "width %u timing %u\n",
1028 mmc_hostname(host), ios->clock, ios->bus_mode,
1029 ios->power_mode, ios->chip_select, ios->vdd,
1030 ios->bus_width, ios->timing);
1033 mmc_set_ungated(host);
1034 host->ops->set_ios(host, ios);
1038 * Control chip select pin on a host.
1040 void mmc_set_chip_select(struct mmc_host *host, int mode)
1042 mmc_host_clk_hold(host);
1043 host->ios.chip_select = mode;
1045 mmc_host_clk_release(host);
1049 * Sets the host clock to the highest possible frequency that
1052 static void __mmc_set_clock(struct mmc_host *host, unsigned int hz)
1054 WARN_ON(hz && hz < host->f_min);
1056 if (hz > host->f_max)
1059 host->ios.clock = hz;
1063 void mmc_set_clock(struct mmc_host *host, unsigned int hz)
1065 mmc_host_clk_hold(host);
1066 __mmc_set_clock(host, hz);
1067 mmc_host_clk_release(host);
1070 #ifdef CONFIG_MMC_CLKGATE
1072 * This gates the clock by setting it to 0 Hz.
1074 void mmc_gate_clock(struct mmc_host *host)
1076 unsigned long flags;
1078 spin_lock_irqsave(&host->clk_lock, flags);
1079 host->clk_old = host->ios.clock;
1080 host->ios.clock = 0;
1081 host->clk_gated = true;
1082 spin_unlock_irqrestore(&host->clk_lock, flags);
1087 * This restores the clock from gating by using the cached
1090 void mmc_ungate_clock(struct mmc_host *host)
1093 * We should previously have gated the clock, so the clock shall
1094 * be 0 here! The clock may however be 0 during initialization,
1095 * when some request operations are performed before setting
1096 * the frequency. When ungate is requested in that situation
1097 * we just ignore the call.
1099 if (host->clk_old) {
1100 BUG_ON(host->ios.clock);
1101 /* This call will also set host->clk_gated to false */
1102 __mmc_set_clock(host, host->clk_old);
1106 void mmc_set_ungated(struct mmc_host *host)
1108 unsigned long flags;
1111 * We've been given a new frequency while the clock is gated,
1112 * so make sure we regard this as ungating it.
1114 spin_lock_irqsave(&host->clk_lock, flags);
1115 host->clk_gated = false;
1116 spin_unlock_irqrestore(&host->clk_lock, flags);
1120 void mmc_set_ungated(struct mmc_host *host)
1125 int mmc_execute_tuning(struct mmc_card *card)
1127 struct mmc_host *host = card->host;
1131 if (!host->ops->execute_tuning)
1134 if (mmc_card_mmc(card))
1135 opcode = MMC_SEND_TUNING_BLOCK_HS200;
1137 opcode = MMC_SEND_TUNING_BLOCK;
1139 mmc_host_clk_hold(host);
1140 err = host->ops->execute_tuning(host, opcode);
1141 mmc_host_clk_release(host);
1144 pr_err("%s: tuning execution failed\n", mmc_hostname(host));
1146 mmc_retune_enable(host);
1152 * Change the bus mode (open drain/push-pull) of a host.
1154 void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode)
1156 mmc_host_clk_hold(host);
1157 host->ios.bus_mode = mode;
1159 mmc_host_clk_release(host);
1163 * Change data bus width of a host.
1165 void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
1167 mmc_host_clk_hold(host);
1168 host->ios.bus_width = width;
1170 mmc_host_clk_release(host);
1174 * Set initial state after a power cycle or a hw_reset.
1176 void mmc_set_initial_state(struct mmc_host *host)
1178 mmc_retune_disable(host);
1180 if (mmc_host_is_spi(host))
1181 host->ios.chip_select = MMC_CS_HIGH;
1183 host->ios.chip_select = MMC_CS_DONTCARE;
1184 host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
1185 host->ios.bus_width = MMC_BUS_WIDTH_1;
1186 host->ios.timing = MMC_TIMING_LEGACY;
1192 * mmc_vdd_to_ocrbitnum - Convert a voltage to the OCR bit number
1193 * @vdd: voltage (mV)
1194 * @low_bits: prefer low bits in boundary cases
1196 * This function returns the OCR bit number according to the provided @vdd
1197 * value. If conversion is not possible a negative errno value returned.
1199 * Depending on the @low_bits flag the function prefers low or high OCR bits
1200 * on boundary voltages. For example,
1201 * with @low_bits = true, 3300 mV translates to ilog2(MMC_VDD_32_33);
1202 * with @low_bits = false, 3300 mV translates to ilog2(MMC_VDD_33_34);
1204 * Any value in the [1951:1999] range translates to the ilog2(MMC_VDD_20_21).
1206 static int mmc_vdd_to_ocrbitnum(int vdd, bool low_bits)
1208 const int max_bit = ilog2(MMC_VDD_35_36);
1211 if (vdd < 1650 || vdd > 3600)
1214 if (vdd >= 1650 && vdd <= 1950)
1215 return ilog2(MMC_VDD_165_195);
1220 /* Base 2000 mV, step 100 mV, bit's base 8. */
1221 bit = (vdd - 2000) / 100 + 8;
1228 * mmc_vddrange_to_ocrmask - Convert a voltage range to the OCR mask
1229 * @vdd_min: minimum voltage value (mV)
1230 * @vdd_max: maximum voltage value (mV)
1232 * This function returns the OCR mask bits according to the provided @vdd_min
1233 * and @vdd_max values. If conversion is not possible the function returns 0.
1235 * Notes wrt boundary cases:
1236 * This function sets the OCR bits for all boundary voltages, for example
1237 * [3300:3400] range is translated to MMC_VDD_32_33 | MMC_VDD_33_34 |
1238 * MMC_VDD_34_35 mask.
1240 u32 mmc_vddrange_to_ocrmask(int vdd_min, int vdd_max)
1244 if (vdd_max < vdd_min)
1247 /* Prefer high bits for the boundary vdd_max values. */
1248 vdd_max = mmc_vdd_to_ocrbitnum(vdd_max, false);
1252 /* Prefer low bits for the boundary vdd_min values. */
1253 vdd_min = mmc_vdd_to_ocrbitnum(vdd_min, true);
1257 /* Fill the mask, from max bit to min bit. */
1258 while (vdd_max >= vdd_min)
1259 mask |= 1 << vdd_max--;
1263 EXPORT_SYMBOL(mmc_vddrange_to_ocrmask);
1268 * mmc_of_parse_voltage - return mask of supported voltages
1269 * @np: The device node need to be parsed.
1270 * @mask: mask of voltages available for MMC/SD/SDIO
1272 * 1. Return zero on success.
1273 * 2. Return negative errno: voltage-range is invalid.
1275 int mmc_of_parse_voltage(struct device_node *np, u32 *mask)
1277 const u32 *voltage_ranges;
1280 voltage_ranges = of_get_property(np, "voltage-ranges", &num_ranges);
1281 num_ranges = num_ranges / sizeof(*voltage_ranges) / 2;
1282 if (!voltage_ranges || !num_ranges) {
1283 pr_info("%s: voltage-ranges unspecified\n", np->full_name);
1287 for (i = 0; i < num_ranges; i++) {
1288 const int j = i * 2;
1291 ocr_mask = mmc_vddrange_to_ocrmask(
1292 be32_to_cpu(voltage_ranges[j]),
1293 be32_to_cpu(voltage_ranges[j + 1]));
1295 pr_err("%s: voltage-range #%d is invalid\n",
1304 EXPORT_SYMBOL(mmc_of_parse_voltage);
1306 #endif /* CONFIG_OF */
1308 static int mmc_of_get_func_num(struct device_node *node)
1313 ret = of_property_read_u32(node, "reg", ®);
1320 struct device_node *mmc_of_find_child_device(struct mmc_host *host,
1323 struct device_node *node;
1325 if (!host->parent || !host->parent->of_node)
1328 for_each_child_of_node(host->parent->of_node, node) {
1329 if (mmc_of_get_func_num(node) == func_num)
1336 #ifdef CONFIG_REGULATOR
1339 * mmc_regulator_get_ocrmask - return mask of supported voltages
1340 * @supply: regulator to use
1342 * This returns either a negative errno, or a mask of voltages that
1343 * can be provided to MMC/SD/SDIO devices using the specified voltage
1344 * regulator. This would normally be called before registering the
1347 int mmc_regulator_get_ocrmask(struct regulator *supply)
1355 count = regulator_count_voltages(supply);
1359 for (i = 0; i < count; i++) {
1360 vdd_uV = regulator_list_voltage(supply, i);
1364 vdd_mV = vdd_uV / 1000;
1365 result |= mmc_vddrange_to_ocrmask(vdd_mV, vdd_mV);
1369 vdd_uV = regulator_get_voltage(supply);
1373 vdd_mV = vdd_uV / 1000;
1374 result = mmc_vddrange_to_ocrmask(vdd_mV, vdd_mV);
1379 EXPORT_SYMBOL_GPL(mmc_regulator_get_ocrmask);
1382 * mmc_regulator_set_ocr - set regulator to match host->ios voltage
1383 * @mmc: the host to regulate
1384 * @supply: regulator to use
1385 * @vdd_bit: zero for power off, else a bit number (host->ios.vdd)
1387 * Returns zero on success, else negative errno.
1389 * MMC host drivers may use this to enable or disable a regulator using
1390 * a particular supply voltage. This would normally be called from the
1393 int mmc_regulator_set_ocr(struct mmc_host *mmc,
1394 struct regulator *supply,
1395 unsigned short vdd_bit)
1404 * REVISIT mmc_vddrange_to_ocrmask() may have set some
1405 * bits this regulator doesn't quite support ... don't
1406 * be too picky, most cards and regulators are OK with
1407 * a 0.1V range goof (it's a small error percentage).
1409 tmp = vdd_bit - ilog2(MMC_VDD_165_195);
1411 min_uV = 1650 * 1000;
1412 max_uV = 1950 * 1000;
1414 min_uV = 1900 * 1000 + tmp * 100 * 1000;
1415 max_uV = min_uV + 100 * 1000;
1418 result = regulator_set_voltage(supply, min_uV, max_uV);
1419 if (result == 0 && !mmc->regulator_enabled) {
1420 result = regulator_enable(supply);
1422 mmc->regulator_enabled = true;
1424 } else if (mmc->regulator_enabled) {
1425 result = regulator_disable(supply);
1427 mmc->regulator_enabled = false;
1431 dev_err(mmc_dev(mmc),
1432 "could not set regulator OCR (%d)\n", result);
1435 EXPORT_SYMBOL_GPL(mmc_regulator_set_ocr);
1437 #endif /* CONFIG_REGULATOR */
1439 int mmc_regulator_get_supply(struct mmc_host *mmc)
1441 struct device *dev = mmc_dev(mmc);
1444 mmc->supply.vmmc = devm_regulator_get_optional(dev, "vmmc");
1445 mmc->supply.vqmmc = devm_regulator_get_optional(dev, "vqmmc");
1447 if (IS_ERR(mmc->supply.vmmc)) {
1448 if (PTR_ERR(mmc->supply.vmmc) == -EPROBE_DEFER)
1449 return -EPROBE_DEFER;
1450 dev_info(dev, "No vmmc regulator found\n");
1452 ret = mmc_regulator_get_ocrmask(mmc->supply.vmmc);
1454 mmc->ocr_avail = ret;
1456 dev_warn(dev, "Failed getting OCR mask: %d\n", ret);
1459 if (IS_ERR(mmc->supply.vqmmc)) {
1460 if (PTR_ERR(mmc->supply.vqmmc) == -EPROBE_DEFER)
1461 return -EPROBE_DEFER;
1462 dev_info(dev, "No vqmmc regulator found\n");
1467 EXPORT_SYMBOL_GPL(mmc_regulator_get_supply);
1470 * Mask off any voltages we don't support and select
1471 * the lowest voltage
1473 u32 mmc_select_voltage(struct mmc_host *host, u32 ocr)
1478 * Sanity check the voltages that the card claims to
1482 dev_warn(mmc_dev(host),
1483 "card claims to support voltages below defined range\n");
1487 ocr &= host->ocr_avail;
1489 dev_warn(mmc_dev(host), "no support for card's volts\n");
1493 if (host->caps2 & MMC_CAP2_FULL_PWR_CYCLE) {
1496 mmc_power_cycle(host, ocr);
1500 if (bit != host->ios.vdd)
1501 dev_warn(mmc_dev(host), "exceeding card's volts\n");
1507 int __mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage)
1510 int old_signal_voltage = host->ios.signal_voltage;
1512 host->ios.signal_voltage = signal_voltage;
1513 if (host->ops->start_signal_voltage_switch) {
1514 mmc_host_clk_hold(host);
1515 err = host->ops->start_signal_voltage_switch(host, &host->ios);
1516 mmc_host_clk_release(host);
1520 host->ios.signal_voltage = old_signal_voltage;
1526 int mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage, u32 ocr)
1528 struct mmc_command cmd = {0};
1535 * Send CMD11 only if the request is to switch the card to
1538 if (signal_voltage == MMC_SIGNAL_VOLTAGE_330)
1539 return __mmc_set_signal_voltage(host, signal_voltage);
1542 * If we cannot switch voltages, return failure so the caller
1543 * can continue without UHS mode
1545 if (!host->ops->start_signal_voltage_switch)
1547 if (!host->ops->card_busy)
1548 pr_warn("%s: cannot verify signal voltage switch\n",
1549 mmc_hostname(host));
1551 mmc_host_clk_hold(host);
1553 cmd.opcode = SD_SWITCH_VOLTAGE;
1555 cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
1557 err = mmc_wait_for_cmd(host, &cmd, 0);
1561 if (!mmc_host_is_spi(host) && (cmd.resp[0] & R1_ERROR)) {
1566 * The card should drive cmd and dat[0:3] low immediately
1567 * after the response of cmd11, but wait 1 ms to be sure
1570 if (host->ops->card_busy && !host->ops->card_busy(host)) {
1575 * During a signal voltage level switch, the clock must be gated
1576 * for 5 ms according to the SD spec
1578 clock = host->ios.clock;
1579 host->ios.clock = 0;
1582 if (__mmc_set_signal_voltage(host, signal_voltage)) {
1584 * Voltages may not have been switched, but we've already
1585 * sent CMD11, so a power cycle is required anyway
1591 /* Keep clock gated for at least 5 ms */
1593 host->ios.clock = clock;
1596 /* Wait for at least 1 ms according to spec */
1600 * Failure to switch is indicated by the card holding
1603 if (host->ops->card_busy && host->ops->card_busy(host))
1608 pr_debug("%s: Signal voltage switch failed, "
1609 "power cycling card\n", mmc_hostname(host));
1610 mmc_power_cycle(host, ocr);
1614 mmc_host_clk_release(host);
1620 * Select timing parameters for host.
1622 void mmc_set_timing(struct mmc_host *host, unsigned int timing)
1624 mmc_host_clk_hold(host);
1625 host->ios.timing = timing;
1627 mmc_host_clk_release(host);
1631 * Select appropriate driver type for host.
1633 void mmc_set_driver_type(struct mmc_host *host, unsigned int drv_type)
1635 mmc_host_clk_hold(host);
1636 host->ios.drv_type = drv_type;
1638 mmc_host_clk_release(host);
1642 * Apply power to the MMC stack. This is a two-stage process.
1643 * First, we enable power to the card without the clock running.
1644 * We then wait a bit for the power to stabilise. Finally,
1645 * enable the bus drivers and clock to the card.
1647 * We must _NOT_ enable the clock prior to power stablising.
1649 * If a host does all the power sequencing itself, ignore the
1650 * initial MMC_POWER_UP stage.
1652 void mmc_power_up(struct mmc_host *host, u32 ocr)
1654 if (host->ios.power_mode == MMC_POWER_ON)
1657 mmc_host_clk_hold(host);
1659 mmc_pwrseq_pre_power_on(host);
1661 host->ios.vdd = fls(ocr) - 1;
1662 host->ios.power_mode = MMC_POWER_UP;
1663 /* Set initial state and call mmc_set_ios */
1664 mmc_set_initial_state(host);
1666 /* Try to set signal voltage to 3.3V but fall back to 1.8v or 1.2v */
1667 if (__mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330) == 0)
1668 dev_dbg(mmc_dev(host), "Initial signal voltage of 3.3v\n");
1669 else if (__mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180) == 0)
1670 dev_dbg(mmc_dev(host), "Initial signal voltage of 1.8v\n");
1671 else if (__mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120) == 0)
1672 dev_dbg(mmc_dev(host), "Initial signal voltage of 1.2v\n");
1675 * This delay should be sufficient to allow the power supply
1676 * to reach the minimum voltage.
1680 mmc_pwrseq_post_power_on(host);
1682 host->ios.clock = host->f_init;
1684 host->ios.power_mode = MMC_POWER_ON;
1688 * This delay must be at least 74 clock sizes, or 1 ms, or the
1689 * time required to reach a stable voltage.
1693 mmc_host_clk_release(host);
1696 void mmc_power_off(struct mmc_host *host)
1698 if (host->ios.power_mode == MMC_POWER_OFF)
1701 mmc_host_clk_hold(host);
1703 mmc_pwrseq_power_off(host);
1705 host->ios.clock = 0;
1708 host->ios.power_mode = MMC_POWER_OFF;
1709 /* Set initial state and call mmc_set_ios */
1710 mmc_set_initial_state(host);
1713 * Some configurations, such as the 802.11 SDIO card in the OLPC
1714 * XO-1.5, require a short delay after poweroff before the card
1715 * can be successfully turned on again.
1719 mmc_host_clk_release(host);
1722 void mmc_power_cycle(struct mmc_host *host, u32 ocr)
1724 mmc_power_off(host);
1725 /* Wait at least 1 ms according to SD spec */
1727 mmc_power_up(host, ocr);
1731 * Cleanup when the last reference to the bus operator is dropped.
1733 static void __mmc_release_bus(struct mmc_host *host)
1736 BUG_ON(host->bus_refs);
1737 BUG_ON(!host->bus_dead);
1739 host->bus_ops = NULL;
1743 * Increase reference count of bus operator
1745 static inline void mmc_bus_get(struct mmc_host *host)
1747 unsigned long flags;
1749 spin_lock_irqsave(&host->lock, flags);
1751 spin_unlock_irqrestore(&host->lock, flags);
1755 * Decrease reference count of bus operator and free it if
1756 * it is the last reference.
1758 static inline void mmc_bus_put(struct mmc_host *host)
1760 unsigned long flags;
1762 spin_lock_irqsave(&host->lock, flags);
1764 if ((host->bus_refs == 0) && host->bus_ops)
1765 __mmc_release_bus(host);
1766 spin_unlock_irqrestore(&host->lock, flags);
1770 * Assign a mmc bus handler to a host. Only one bus handler may control a
1771 * host at any given time.
1773 void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops)
1775 unsigned long flags;
1780 WARN_ON(!host->claimed);
1782 spin_lock_irqsave(&host->lock, flags);
1784 BUG_ON(host->bus_ops);
1785 BUG_ON(host->bus_refs);
1787 host->bus_ops = ops;
1791 spin_unlock_irqrestore(&host->lock, flags);
1795 * Remove the current bus handler from a host.
1797 void mmc_detach_bus(struct mmc_host *host)
1799 unsigned long flags;
1803 WARN_ON(!host->claimed);
1804 WARN_ON(!host->bus_ops);
1806 spin_lock_irqsave(&host->lock, flags);
1810 spin_unlock_irqrestore(&host->lock, flags);
1815 static void _mmc_detect_change(struct mmc_host *host, unsigned long delay,
1818 #ifdef CONFIG_MMC_DEBUG
1819 unsigned long flags;
1820 spin_lock_irqsave(&host->lock, flags);
1821 WARN_ON(host->removed);
1822 spin_unlock_irqrestore(&host->lock, flags);
1826 * If the device is configured as wakeup, we prevent a new sleep for
1827 * 5 s to give provision for user space to consume the event.
1829 if (cd_irq && !(host->caps & MMC_CAP_NEEDS_POLL) &&
1830 device_can_wakeup(mmc_dev(host)))
1831 pm_wakeup_event(mmc_dev(host), 5000);
1833 host->detect_change = 1;
1834 mmc_schedule_delayed_work(&host->detect, delay);
1838 * mmc_detect_change - process change of state on a MMC socket
1839 * @host: host which changed state.
1840 * @delay: optional delay to wait before detection (jiffies)
1842 * MMC drivers should call this when they detect a card has been
1843 * inserted or removed. The MMC layer will confirm that any
1844 * present card is still functional, and initialize any newly
1847 void mmc_detect_change(struct mmc_host *host, unsigned long delay)
1849 _mmc_detect_change(host, delay, true);
1851 EXPORT_SYMBOL(mmc_detect_change);
1853 void mmc_init_erase(struct mmc_card *card)
1857 if (is_power_of_2(card->erase_size))
1858 card->erase_shift = ffs(card->erase_size) - 1;
1860 card->erase_shift = 0;
1863 * It is possible to erase an arbitrarily large area of an SD or MMC
1864 * card. That is not desirable because it can take a long time
1865 * (minutes) potentially delaying more important I/O, and also the
1866 * timeout calculations become increasingly hugely over-estimated.
1867 * Consequently, 'pref_erase' is defined as a guide to limit erases
1868 * to that size and alignment.
1870 * For SD cards that define Allocation Unit size, limit erases to one
1871 * Allocation Unit at a time. For MMC cards that define High Capacity
1872 * Erase Size, whether it is switched on or not, limit to that size.
1873 * Otherwise just have a stab at a good value. For modern cards it
1874 * will end up being 4MiB. Note that if the value is too small, it
1875 * can end up taking longer to erase.
1877 if (mmc_card_sd(card) && card->ssr.au) {
1878 card->pref_erase = card->ssr.au;
1879 card->erase_shift = ffs(card->ssr.au) - 1;
1880 } else if (card->ext_csd.hc_erase_size) {
1881 card->pref_erase = card->ext_csd.hc_erase_size;
1882 } else if (card->erase_size) {
1883 sz = (card->csd.capacity << (card->csd.read_blkbits - 9)) >> 11;
1885 card->pref_erase = 512 * 1024 / 512;
1887 card->pref_erase = 1024 * 1024 / 512;
1889 card->pref_erase = 2 * 1024 * 1024 / 512;
1891 card->pref_erase = 4 * 1024 * 1024 / 512;
1892 if (card->pref_erase < card->erase_size)
1893 card->pref_erase = card->erase_size;
1895 sz = card->pref_erase % card->erase_size;
1897 card->pref_erase += card->erase_size - sz;
1900 card->pref_erase = 0;
1903 static unsigned int mmc_mmc_erase_timeout(struct mmc_card *card,
1904 unsigned int arg, unsigned int qty)
1906 unsigned int erase_timeout;
1908 if (arg == MMC_DISCARD_ARG ||
1909 (arg == MMC_TRIM_ARG && card->ext_csd.rev >= 6)) {
1910 erase_timeout = card->ext_csd.trim_timeout;
1911 } else if (card->ext_csd.erase_group_def & 1) {
1912 /* High Capacity Erase Group Size uses HC timeouts */
1913 if (arg == MMC_TRIM_ARG)
1914 erase_timeout = card->ext_csd.trim_timeout;
1916 erase_timeout = card->ext_csd.hc_erase_timeout;
1918 /* CSD Erase Group Size uses write timeout */
1919 unsigned int mult = (10 << card->csd.r2w_factor);
1920 unsigned int timeout_clks = card->csd.tacc_clks * mult;
1921 unsigned int timeout_us;
1923 /* Avoid overflow: e.g. tacc_ns=80000000 mult=1280 */
1924 if (card->csd.tacc_ns < 1000000)
1925 timeout_us = (card->csd.tacc_ns * mult) / 1000;
1927 timeout_us = (card->csd.tacc_ns / 1000) * mult;
1930 * ios.clock is only a target. The real clock rate might be
1931 * less but not that much less, so fudge it by multiplying by 2.
1934 timeout_us += (timeout_clks * 1000) /
1935 (mmc_host_clk_rate(card->host) / 1000);
1937 erase_timeout = timeout_us / 1000;
1940 * Theoretically, the calculation could underflow so round up
1941 * to 1ms in that case.
1947 /* Multiplier for secure operations */
1948 if (arg & MMC_SECURE_ARGS) {
1949 if (arg == MMC_SECURE_ERASE_ARG)
1950 erase_timeout *= card->ext_csd.sec_erase_mult;
1952 erase_timeout *= card->ext_csd.sec_trim_mult;
1955 erase_timeout *= qty;
1958 * Ensure at least a 1 second timeout for SPI as per
1959 * 'mmc_set_data_timeout()'
1961 if (mmc_host_is_spi(card->host) && erase_timeout < 1000)
1962 erase_timeout = 1000;
1964 return erase_timeout;
1967 static unsigned int mmc_sd_erase_timeout(struct mmc_card *card,
1971 unsigned int erase_timeout;
1973 if (card->ssr.erase_timeout) {
1974 /* Erase timeout specified in SD Status Register (SSR) */
1975 erase_timeout = card->ssr.erase_timeout * qty +
1976 card->ssr.erase_offset;
1979 * Erase timeout not specified in SD Status Register (SSR) so
1980 * use 250ms per write block.
1982 erase_timeout = 250 * qty;
1985 /* Must not be less than 1 second */
1986 if (erase_timeout < 1000)
1987 erase_timeout = 1000;
1989 return erase_timeout;
1992 static unsigned int mmc_erase_timeout(struct mmc_card *card,
1996 if (mmc_card_sd(card))
1997 return mmc_sd_erase_timeout(card, arg, qty);
1999 return mmc_mmc_erase_timeout(card, arg, qty);
2002 static int mmc_do_erase(struct mmc_card *card, unsigned int from,
2003 unsigned int to, unsigned int arg)
2005 struct mmc_command cmd = {0};
2006 unsigned int qty = 0;
2007 unsigned long timeout;
2010 mmc_retune_hold(card->host);
2013 * qty is used to calculate the erase timeout which depends on how many
2014 * erase groups (or allocation units in SD terminology) are affected.
2015 * We count erasing part of an erase group as one erase group.
2016 * For SD, the allocation units are always a power of 2. For MMC, the
2017 * erase group size is almost certainly also power of 2, but it does not
2018 * seem to insist on that in the JEDEC standard, so we fall back to
2019 * division in that case. SD may not specify an allocation unit size,
2020 * in which case the timeout is based on the number of write blocks.
2022 * Note that the timeout for secure trim 2 will only be correct if the
2023 * number of erase groups specified is the same as the total of all
2024 * preceding secure trim 1 commands. Since the power may have been
2025 * lost since the secure trim 1 commands occurred, it is generally
2026 * impossible to calculate the secure trim 2 timeout correctly.
2028 if (card->erase_shift)
2029 qty += ((to >> card->erase_shift) -
2030 (from >> card->erase_shift)) + 1;
2031 else if (mmc_card_sd(card))
2032 qty += to - from + 1;
2034 qty += ((to / card->erase_size) -
2035 (from / card->erase_size)) + 1;
2037 if (!mmc_card_blockaddr(card)) {
2042 if (mmc_card_sd(card))
2043 cmd.opcode = SD_ERASE_WR_BLK_START;
2045 cmd.opcode = MMC_ERASE_GROUP_START;
2047 cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
2048 err = mmc_wait_for_cmd(card->host, &cmd, 0);
2050 pr_err("mmc_erase: group start error %d, "
2051 "status %#x\n", err, cmd.resp[0]);
2056 memset(&cmd, 0, sizeof(struct mmc_command));
2057 if (mmc_card_sd(card))
2058 cmd.opcode = SD_ERASE_WR_BLK_END;
2060 cmd.opcode = MMC_ERASE_GROUP_END;
2062 cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
2063 err = mmc_wait_for_cmd(card->host, &cmd, 0);
2065 pr_err("mmc_erase: group end error %d, status %#x\n",
2071 memset(&cmd, 0, sizeof(struct mmc_command));
2072 cmd.opcode = MMC_ERASE;
2074 cmd.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
2075 cmd.busy_timeout = mmc_erase_timeout(card, arg, qty);
2076 err = mmc_wait_for_cmd(card->host, &cmd, 0);
2078 pr_err("mmc_erase: erase error %d, status %#x\n",
2084 if (mmc_host_is_spi(card->host))
2087 timeout = jiffies + msecs_to_jiffies(MMC_CORE_TIMEOUT_MS);
2089 memset(&cmd, 0, sizeof(struct mmc_command));
2090 cmd.opcode = MMC_SEND_STATUS;
2091 cmd.arg = card->rca << 16;
2092 cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
2093 /* Do not retry else we can't see errors */
2094 err = mmc_wait_for_cmd(card->host, &cmd, 0);
2095 if (err || (cmd.resp[0] & 0xFDF92000)) {
2096 pr_err("error %d requesting status %#x\n",
2102 /* Timeout if the device never becomes ready for data and
2103 * never leaves the program state.
2105 if (time_after(jiffies, timeout)) {
2106 pr_err("%s: Card stuck in programming state! %s\n",
2107 mmc_hostname(card->host), __func__);
2112 } while (!(cmd.resp[0] & R1_READY_FOR_DATA) ||
2113 (R1_CURRENT_STATE(cmd.resp[0]) == R1_STATE_PRG));
2115 mmc_retune_release(card->host);
2120 * mmc_erase - erase sectors.
2121 * @card: card to erase
2122 * @from: first sector to erase
2123 * @nr: number of sectors to erase
2124 * @arg: erase command argument (SD supports only %MMC_ERASE_ARG)
2126 * Caller must claim host before calling this function.
2128 int mmc_erase(struct mmc_card *card, unsigned int from, unsigned int nr,
2131 unsigned int rem, to = from + nr;
2133 if (!(card->host->caps & MMC_CAP_ERASE) ||
2134 !(card->csd.cmdclass & CCC_ERASE))
2137 if (!card->erase_size)
2140 if (mmc_card_sd(card) && arg != MMC_ERASE_ARG)
2143 if ((arg & MMC_SECURE_ARGS) &&
2144 !(card->ext_csd.sec_feature_support & EXT_CSD_SEC_ER_EN))
2147 if ((arg & MMC_TRIM_ARGS) &&
2148 !(card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN))
2151 if (arg == MMC_SECURE_ERASE_ARG) {
2152 if (from % card->erase_size || nr % card->erase_size)
2156 if (arg == MMC_ERASE_ARG) {
2157 rem = from % card->erase_size;
2159 rem = card->erase_size - rem;
2166 rem = nr % card->erase_size;
2179 /* 'from' and 'to' are inclusive */
2182 return mmc_do_erase(card, from, to, arg);
2184 EXPORT_SYMBOL(mmc_erase);
2186 int mmc_can_erase(struct mmc_card *card)
2188 if ((card->host->caps & MMC_CAP_ERASE) &&
2189 (card->csd.cmdclass & CCC_ERASE) && card->erase_size)
2193 EXPORT_SYMBOL(mmc_can_erase);
2195 int mmc_can_trim(struct mmc_card *card)
2197 if (card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN)
2201 EXPORT_SYMBOL(mmc_can_trim);
2203 int mmc_can_discard(struct mmc_card *card)
2206 * As there's no way to detect the discard support bit at v4.5
2207 * use the s/w feature support filed.
2209 if (card->ext_csd.feature_support & MMC_DISCARD_FEATURE)
2213 EXPORT_SYMBOL(mmc_can_discard);
2215 int mmc_can_sanitize(struct mmc_card *card)
2217 if (!mmc_can_trim(card) && !mmc_can_erase(card))
2219 if (card->ext_csd.sec_feature_support & EXT_CSD_SEC_SANITIZE)
2223 EXPORT_SYMBOL(mmc_can_sanitize);
2225 int mmc_can_secure_erase_trim(struct mmc_card *card)
2227 if ((card->ext_csd.sec_feature_support & EXT_CSD_SEC_ER_EN) &&
2228 !(card->quirks & MMC_QUIRK_SEC_ERASE_TRIM_BROKEN))
2232 EXPORT_SYMBOL(mmc_can_secure_erase_trim);
2234 int mmc_erase_group_aligned(struct mmc_card *card, unsigned int from,
2237 if (!card->erase_size)
2239 if (from % card->erase_size || nr % card->erase_size)
2243 EXPORT_SYMBOL(mmc_erase_group_aligned);
2245 static unsigned int mmc_do_calc_max_discard(struct mmc_card *card,
2248 struct mmc_host *host = card->host;
2249 unsigned int max_discard, x, y, qty = 0, max_qty, timeout;
2250 unsigned int last_timeout = 0;
2252 if (card->erase_shift)
2253 max_qty = UINT_MAX >> card->erase_shift;
2254 else if (mmc_card_sd(card))
2257 max_qty = UINT_MAX / card->erase_size;
2259 /* Find the largest qty with an OK timeout */
2262 for (x = 1; x && x <= max_qty && max_qty - x >= qty; x <<= 1) {
2263 timeout = mmc_erase_timeout(card, arg, qty + x);
2264 if (timeout > host->max_busy_timeout)
2266 if (timeout < last_timeout)
2268 last_timeout = timeout;
2280 /* Convert qty to sectors */
2281 if (card->erase_shift)
2282 max_discard = --qty << card->erase_shift;
2283 else if (mmc_card_sd(card))
2286 max_discard = --qty * card->erase_size;
2291 unsigned int mmc_calc_max_discard(struct mmc_card *card)
2293 struct mmc_host *host = card->host;
2294 unsigned int max_discard, max_trim;
2296 if (!host->max_busy_timeout)
2300 * Without erase_group_def set, MMC erase timeout depends on clock
2301 * frequence which can change. In that case, the best choice is
2302 * just the preferred erase size.
2304 if (mmc_card_mmc(card) && !(card->ext_csd.erase_group_def & 1))
2305 return card->pref_erase;
2307 max_discard = mmc_do_calc_max_discard(card, MMC_ERASE_ARG);
2308 if (mmc_can_trim(card)) {
2309 max_trim = mmc_do_calc_max_discard(card, MMC_TRIM_ARG);
2310 if (max_trim < max_discard)
2311 max_discard = max_trim;
2312 } else if (max_discard < card->erase_size) {
2315 pr_debug("%s: calculated max. discard sectors %u for timeout %u ms\n",
2316 mmc_hostname(host), max_discard, host->max_busy_timeout);
2319 EXPORT_SYMBOL(mmc_calc_max_discard);
2321 int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen)
2323 struct mmc_command cmd = {0};
2325 if (mmc_card_blockaddr(card) || mmc_card_ddr52(card))
2328 cmd.opcode = MMC_SET_BLOCKLEN;
2330 cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
2331 return mmc_wait_for_cmd(card->host, &cmd, 5);
2333 EXPORT_SYMBOL(mmc_set_blocklen);
2335 int mmc_set_blockcount(struct mmc_card *card, unsigned int blockcount,
2338 struct mmc_command cmd = {0};
2340 cmd.opcode = MMC_SET_BLOCK_COUNT;
2341 cmd.arg = blockcount & 0x0000FFFF;
2344 cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
2345 return mmc_wait_for_cmd(card->host, &cmd, 5);
2347 EXPORT_SYMBOL(mmc_set_blockcount);
2349 static void mmc_hw_reset_for_init(struct mmc_host *host)
2351 if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
2353 mmc_host_clk_hold(host);
2354 host->ops->hw_reset(host);
2355 mmc_host_clk_release(host);
2358 int mmc_hw_reset(struct mmc_host *host)
2366 if (!host->bus_ops || host->bus_dead || !host->bus_ops->reset) {
2371 ret = host->bus_ops->reset(host);
2374 pr_warn("%s: tried to reset card\n", mmc_hostname(host));
2378 EXPORT_SYMBOL(mmc_hw_reset);
2380 static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
2382 host->f_init = freq;
2384 #ifdef CONFIG_MMC_DEBUG
2385 pr_info("%s: %s: trying to init card at %u Hz\n",
2386 mmc_hostname(host), __func__, host->f_init);
2388 mmc_power_up(host, host->ocr_avail);
2391 * Some eMMCs (with VCCQ always on) may not be reset after power up, so
2392 * do a hardware reset if possible.
2394 mmc_hw_reset_for_init(host);
2397 * sdio_reset sends CMD52 to reset card. Since we do not know
2398 * if the card is being re-initialized, just send it. CMD52
2399 * should be ignored by SD/eMMC cards.
2404 mmc_send_if_cond(host, host->ocr_avail);
2406 /* Order's important: probe SDIO, then SD, then MMC */
2407 if (!mmc_attach_sdio(host))
2409 if (!mmc_attach_sd(host))
2411 if (!mmc_attach_mmc(host))
2414 mmc_power_off(host);
2418 int _mmc_detect_card_removed(struct mmc_host *host)
2422 if (host->caps & MMC_CAP_NONREMOVABLE)
2425 if (!host->card || mmc_card_removed(host->card))
2428 ret = host->bus_ops->alive(host);
2431 * Card detect status and alive check may be out of sync if card is
2432 * removed slowly, when card detect switch changes while card/slot
2433 * pads are still contacted in hardware (refer to "SD Card Mechanical
2434 * Addendum, Appendix C: Card Detection Switch"). So reschedule a
2435 * detect work 200ms later for this case.
2437 if (!ret && host->ops->get_cd && !host->ops->get_cd(host)) {
2438 mmc_detect_change(host, msecs_to_jiffies(200));
2439 pr_debug("%s: card removed too slowly\n", mmc_hostname(host));
2443 mmc_card_set_removed(host->card);
2444 pr_debug("%s: card remove detected\n", mmc_hostname(host));
2450 int mmc_detect_card_removed(struct mmc_host *host)
2452 struct mmc_card *card = host->card;
2455 WARN_ON(!host->claimed);
2460 ret = mmc_card_removed(card);
2462 * The card will be considered unchanged unless we have been asked to
2463 * detect a change or host requires polling to provide card detection.
2465 if (!host->detect_change && !(host->caps & MMC_CAP_NEEDS_POLL))
2468 host->detect_change = 0;
2470 ret = _mmc_detect_card_removed(host);
2471 if (ret && (host->caps & MMC_CAP_NEEDS_POLL)) {
2473 * Schedule a detect work as soon as possible to let a
2474 * rescan handle the card removal.
2476 cancel_delayed_work(&host->detect);
2477 _mmc_detect_change(host, 0, false);
2483 EXPORT_SYMBOL(mmc_detect_card_removed);
2485 void mmc_rescan(struct work_struct *work)
2487 struct mmc_host *host =
2488 container_of(work, struct mmc_host, detect.work);
2491 if (host->trigger_card_event && host->ops->card_event) {
2492 host->ops->card_event(host);
2493 host->trigger_card_event = false;
2496 if (host->rescan_disable)
2499 /* If there is a non-removable card registered, only scan once */
2500 if ((host->caps & MMC_CAP_NONREMOVABLE) && host->rescan_entered)
2502 host->rescan_entered = 1;
2507 * if there is a _removable_ card registered, check whether it is
2510 if (host->bus_ops && !host->bus_dead
2511 && !(host->caps & MMC_CAP_NONREMOVABLE))
2512 host->bus_ops->detect(host);
2514 host->detect_change = 0;
2517 * Let mmc_bus_put() free the bus/bus_ops if we've found that
2518 * the card is no longer present.
2523 /* if there still is a card present, stop here */
2524 if (host->bus_ops != NULL) {
2530 * Only we can add a new handler, so it's safe to
2531 * release the lock here.
2535 if (!(host->caps & MMC_CAP_NONREMOVABLE) && host->ops->get_cd &&
2536 host->ops->get_cd(host) == 0) {
2537 mmc_claim_host(host);
2538 mmc_power_off(host);
2539 mmc_release_host(host);
2543 mmc_claim_host(host);
2544 for (i = 0; i < ARRAY_SIZE(freqs); i++) {
2545 if (!mmc_rescan_try_freq(host, max(freqs[i], host->f_min)))
2547 if (freqs[i] <= host->f_min)
2550 mmc_release_host(host);
2553 if (host->caps & MMC_CAP_NEEDS_POLL)
2554 mmc_schedule_delayed_work(&host->detect, HZ);
2557 void mmc_start_host(struct mmc_host *host)
2559 host->f_init = max(freqs[0], host->f_min);
2560 host->rescan_disable = 0;
2561 host->ios.power_mode = MMC_POWER_UNDEFINED;
2562 if (host->caps2 & MMC_CAP2_NO_PRESCAN_POWERUP)
2563 mmc_power_off(host);
2565 mmc_power_up(host, host->ocr_avail);
2566 mmc_gpiod_request_cd_irq(host);
2567 _mmc_detect_change(host, 0, false);
2570 void mmc_stop_host(struct mmc_host *host)
2572 #ifdef CONFIG_MMC_DEBUG
2573 unsigned long flags;
2574 spin_lock_irqsave(&host->lock, flags);
2576 spin_unlock_irqrestore(&host->lock, flags);
2578 if (host->slot.cd_irq >= 0)
2579 disable_irq(host->slot.cd_irq);
2581 host->rescan_disable = 1;
2582 cancel_delayed_work_sync(&host->detect);
2583 mmc_flush_scheduled_work();
2585 /* clear pm flags now and let card drivers set them as needed */
2589 if (host->bus_ops && !host->bus_dead) {
2590 /* Calling bus_ops->remove() with a claimed host can deadlock */
2591 host->bus_ops->remove(host);
2592 mmc_claim_host(host);
2593 mmc_detach_bus(host);
2594 mmc_power_off(host);
2595 mmc_release_host(host);
2603 mmc_power_off(host);
2606 int mmc_power_save_host(struct mmc_host *host)
2610 #ifdef CONFIG_MMC_DEBUG
2611 pr_info("%s: %s: powering down\n", mmc_hostname(host), __func__);
2616 if (!host->bus_ops || host->bus_dead) {
2621 if (host->bus_ops->power_save)
2622 ret = host->bus_ops->power_save(host);
2626 mmc_power_off(host);
2630 EXPORT_SYMBOL(mmc_power_save_host);
2632 int mmc_power_restore_host(struct mmc_host *host)
2636 #ifdef CONFIG_MMC_DEBUG
2637 pr_info("%s: %s: powering up\n", mmc_hostname(host), __func__);
2642 if (!host->bus_ops || host->bus_dead) {
2647 mmc_power_up(host, host->card->ocr);
2648 ret = host->bus_ops->power_restore(host);
2654 EXPORT_SYMBOL(mmc_power_restore_host);
2657 * Flush the cache to the non-volatile storage.
2659 int mmc_flush_cache(struct mmc_card *card)
2663 if (mmc_card_mmc(card) &&
2664 (card->ext_csd.cache_size > 0) &&
2665 (card->ext_csd.cache_ctrl & 1)) {
2666 err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
2667 EXT_CSD_FLUSH_CACHE, 1, 0);
2669 pr_err("%s: cache flush error %d\n",
2670 mmc_hostname(card->host), err);
2675 EXPORT_SYMBOL(mmc_flush_cache);
2679 /* Do the card removal on suspend if card is assumed removeable
2680 * Do that in pm notifier while userspace isn't yet frozen, so we will be able
2683 int mmc_pm_notify(struct notifier_block *notify_block,
2684 unsigned long mode, void *unused)
2686 struct mmc_host *host = container_of(
2687 notify_block, struct mmc_host, pm_notify);
2688 unsigned long flags;
2692 case PM_HIBERNATION_PREPARE:
2693 case PM_SUSPEND_PREPARE:
2694 case PM_RESTORE_PREPARE:
2695 spin_lock_irqsave(&host->lock, flags);
2696 host->rescan_disable = 1;
2697 spin_unlock_irqrestore(&host->lock, flags);
2698 cancel_delayed_work_sync(&host->detect);
2703 /* Validate prerequisites for suspend */
2704 if (host->bus_ops->pre_suspend)
2705 err = host->bus_ops->pre_suspend(host);
2709 /* Calling bus_ops->remove() with a claimed host can deadlock */
2710 host->bus_ops->remove(host);
2711 mmc_claim_host(host);
2712 mmc_detach_bus(host);
2713 mmc_power_off(host);
2714 mmc_release_host(host);
2718 case PM_POST_SUSPEND:
2719 case PM_POST_HIBERNATION:
2720 case PM_POST_RESTORE:
2722 spin_lock_irqsave(&host->lock, flags);
2723 host->rescan_disable = 0;
2724 spin_unlock_irqrestore(&host->lock, flags);
2725 _mmc_detect_change(host, 0, false);
2734 * mmc_init_context_info() - init synchronization context
2737 * Init struct context_info needed to implement asynchronous
2738 * request mechanism, used by mmc core, host driver and mmc requests
2741 void mmc_init_context_info(struct mmc_host *host)
2743 spin_lock_init(&host->context_info.lock);
2744 host->context_info.is_new_req = false;
2745 host->context_info.is_done_rcv = false;
2746 host->context_info.is_waiting_last_req = false;
2747 init_waitqueue_head(&host->context_info.wait);
2750 static int __init mmc_init(void)
2754 workqueue = alloc_ordered_workqueue("kmmcd", 0);
2758 ret = mmc_register_bus();
2760 goto destroy_workqueue;
2762 ret = mmc_register_host_class();
2764 goto unregister_bus;
2766 ret = sdio_register_bus();
2768 goto unregister_host_class;
2772 unregister_host_class:
2773 mmc_unregister_host_class();
2775 mmc_unregister_bus();
2777 destroy_workqueue(workqueue);
2782 static void __exit mmc_exit(void)
2784 sdio_unregister_bus();
2785 mmc_unregister_host_class();
2786 mmc_unregister_bus();
2787 destroy_workqueue(workqueue);
2790 subsys_initcall(mmc_init);
2791 module_exit(mmc_exit);
2793 MODULE_LICENSE("GPL");