linux/drivers/mmc/mmc.c
Philip Langdale fba68bd2da mmc: Add support for SDHC cards
Thanks to the generous donation of an SDHC card by John Gilmore, and
the surprisingly enlightened decision by the SD Card Association to
publish useful specs, I've been able to bash out support for SDHC. The
changes are not too profound:

i) Add a card flag indicating the card uses block level addressing and
check it in the block driver. As we never took advantage of byte-level
addressing, this simply involves skipping the block -> byte
translation when sending commands.

ii) The layout of the CSD is changed - a set of fields are discarded
to make space for a larger C_SIZE. We did not reference any of the
discarded fields except those related to the C_SIZE.

iii) Read and write timeouts are fixed values and not calculated from
CSD values.

iv) Before invoking SEND_APP_OP_COND, we must invoke the new
SEND_IF_COND to inform the card we support SDHC.

Signed-off-by: Philipl Langdale <philipl@overt.org>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
2007-02-04 20:54:07 +01:00

1706 lines
39 KiB
C

/*
* linux/drivers/mmc/mmc.c
*
* Copyright (C) 2003-2004 Russell King, All Rights Reserved.
* SD support Copyright (C) 2004 Ian Molton, All Rights Reserved.
* SD support Copyright (C) 2005 Pierre Ossman, All Rights Reserved.
* MMCv4 support Copyright (C) 2006 Philip Langdale, All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/completion.h>
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/pagemap.h>
#include <linux/err.h>
#include <asm/scatterlist.h>
#include <linux/scatterlist.h>
#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
#include <linux/mmc/protocol.h>
#include "mmc.h"
#define CMD_RETRIES 3
/*
* OCR Bit positions to 10s of Vdd mV.
*/
static const unsigned short mmc_ocr_bit_to_vdd[] = {
150, 155, 160, 165, 170, 180, 190, 200,
210, 220, 230, 240, 250, 260, 270, 280,
290, 300, 310, 320, 330, 340, 350, 360
};
static const unsigned int tran_exp[] = {
10000, 100000, 1000000, 10000000,
0, 0, 0, 0
};
static const unsigned char tran_mant[] = {
0, 10, 12, 13, 15, 20, 25, 30,
35, 40, 45, 50, 55, 60, 70, 80,
};
static const unsigned int tacc_exp[] = {
1, 10, 100, 1000, 10000, 100000, 1000000, 10000000,
};
static const unsigned int tacc_mant[] = {
0, 10, 12, 13, 15, 20, 25, 30,
35, 40, 45, 50, 55, 60, 70, 80,
};
/**
* mmc_request_done - finish processing an MMC request
* @host: MMC host which completed request
* @mrq: MMC request which request
*
* MMC drivers should call this function when they have completed
* their processing of a request.
*/
void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
{
struct mmc_command *cmd = mrq->cmd;
int err = cmd->error;
pr_debug("%s: req done (CMD%u): %d/%d/%d: %08x %08x %08x %08x\n",
mmc_hostname(host), cmd->opcode, err,
mrq->data ? mrq->data->error : 0,
mrq->stop ? mrq->stop->error : 0,
cmd->resp[0], cmd->resp[1], cmd->resp[2], cmd->resp[3]);
if (err && cmd->retries) {
cmd->retries--;
cmd->error = 0;
host->ops->request(host, mrq);
} else if (mrq->done) {
mrq->done(mrq);
}
}
EXPORT_SYMBOL(mmc_request_done);
/**
* mmc_start_request - start a command on a host
* @host: MMC host to start command on
* @mrq: MMC request to start
*
* Queue a command on the specified host. We expect the
* caller to be holding the host lock with interrupts disabled.
*/
void
mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
{
pr_debug("%s: starting CMD%u arg %08x flags %08x\n",
mmc_hostname(host), mrq->cmd->opcode,
mrq->cmd->arg, mrq->cmd->flags);
WARN_ON(!host->claimed);
mrq->cmd->error = 0;
mrq->cmd->mrq = mrq;
if (mrq->data) {
mrq->cmd->data = mrq->data;
mrq->data->error = 0;
mrq->data->mrq = mrq;
if (mrq->stop) {
mrq->data->stop = mrq->stop;
mrq->stop->error = 0;
mrq->stop->mrq = mrq;
}
}
host->ops->request(host, mrq);
}
EXPORT_SYMBOL(mmc_start_request);
static void mmc_wait_done(struct mmc_request *mrq)
{
complete(mrq->done_data);
}
int mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq)
{
DECLARE_COMPLETION_ONSTACK(complete);
mrq->done_data = &complete;
mrq->done = mmc_wait_done;
mmc_start_request(host, mrq);
wait_for_completion(&complete);
return 0;
}
EXPORT_SYMBOL(mmc_wait_for_req);
/**
* mmc_wait_for_cmd - start a command and wait for completion
* @host: MMC host to start command
* @cmd: MMC command to start
* @retries: maximum number of retries
*
* Start a new MMC command for a host, and wait for the command
* to complete. Return any error that occurred while the command
* was executing. Do not attempt to parse the response.
*/
int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries)
{
struct mmc_request mrq;
BUG_ON(!host->claimed);
memset(&mrq, 0, sizeof(struct mmc_request));
memset(cmd->resp, 0, sizeof(cmd->resp));
cmd->retries = retries;
mrq.cmd = cmd;
cmd->data = NULL;
mmc_wait_for_req(host, &mrq);
return cmd->error;
}
EXPORT_SYMBOL(mmc_wait_for_cmd);
/**
* mmc_wait_for_app_cmd - start an application command and wait for
completion
* @host: MMC host to start command
* @rca: RCA to send MMC_APP_CMD to
* @cmd: MMC command to start
* @retries: maximum number of retries
*
* Sends a MMC_APP_CMD, checks the card response, sends the command
* in the parameter and waits for it to complete. Return any error
* that occurred while the command was executing. Do not attempt to
* parse the response.
*/
int mmc_wait_for_app_cmd(struct mmc_host *host, unsigned int rca,
struct mmc_command *cmd, int retries)
{
struct mmc_request mrq;
struct mmc_command appcmd;
int i, err;
BUG_ON(!host->claimed);
BUG_ON(retries < 0);
err = MMC_ERR_INVALID;
/*
* We have to resend MMC_APP_CMD for each attempt so
* we cannot use the retries field in mmc_command.
*/
for (i = 0;i <= retries;i++) {
memset(&mrq, 0, sizeof(struct mmc_request));
appcmd.opcode = MMC_APP_CMD;
appcmd.arg = rca << 16;
appcmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
appcmd.retries = 0;
memset(appcmd.resp, 0, sizeof(appcmd.resp));
appcmd.data = NULL;
mrq.cmd = &appcmd;
appcmd.data = NULL;
mmc_wait_for_req(host, &mrq);
if (appcmd.error) {
err = appcmd.error;
continue;
}
/* Check that card supported application commands */
if (!(appcmd.resp[0] & R1_APP_CMD))
return MMC_ERR_FAILED;
memset(&mrq, 0, sizeof(struct mmc_request));
memset(cmd->resp, 0, sizeof(cmd->resp));
cmd->retries = 0;
mrq.cmd = cmd;
cmd->data = NULL;
mmc_wait_for_req(host, &mrq);
err = cmd->error;
if (cmd->error == MMC_ERR_NONE)
break;
}
return err;
}
EXPORT_SYMBOL(mmc_wait_for_app_cmd);
/**
* mmc_set_data_timeout - set the timeout for a data command
* @data: data phase for command
* @card: the MMC card associated with the data transfer
* @write: flag to differentiate reads from writes
*/
void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card,
int write)
{
unsigned int mult;
/*
* SD cards use a 100 multiplier rather than 10
*/
mult = mmc_card_sd(card) ? 100 : 10;
/*
* Scale up the multiplier (and therefore the timeout) by
* the r2w factor for writes.
*/
if (write)
mult <<= card->csd.r2w_factor;
data->timeout_ns = card->csd.tacc_ns * mult;
data->timeout_clks = card->csd.tacc_clks * mult;
/*
* SD cards also have an upper limit on the timeout.
*/
if (mmc_card_sd(card)) {
unsigned int timeout_us, limit_us;
timeout_us = data->timeout_ns / 1000;
timeout_us += data->timeout_clks * 1000 /
(card->host->ios.clock / 1000);
if (write)
limit_us = 250000;
else
limit_us = 100000;
/*
* SDHC cards always use these fixed values.
*/
if (timeout_us > limit_us || mmc_card_blockaddr(card)) {
data->timeout_ns = limit_us * 1000;
data->timeout_clks = 0;
}
}
}
EXPORT_SYMBOL(mmc_set_data_timeout);
static int mmc_select_card(struct mmc_host *host, struct mmc_card *card);
/**
* __mmc_claim_host - exclusively claim a host
* @host: mmc host to claim
* @card: mmc card to claim host for
*
* Claim a host for a set of operations. If a valid card
* is passed and this wasn't the last card selected, select
* the card before returning.
*
* Note: you should use mmc_card_claim_host or mmc_claim_host.
*/
int __mmc_claim_host(struct mmc_host *host, struct mmc_card *card)
{
DECLARE_WAITQUEUE(wait, current);
unsigned long flags;
int err = 0;
add_wait_queue(&host->wq, &wait);
spin_lock_irqsave(&host->lock, flags);
while (1) {
set_current_state(TASK_UNINTERRUPTIBLE);
if (!host->claimed)
break;
spin_unlock_irqrestore(&host->lock, flags);
schedule();
spin_lock_irqsave(&host->lock, flags);
}
set_current_state(TASK_RUNNING);
host->claimed = 1;
spin_unlock_irqrestore(&host->lock, flags);
remove_wait_queue(&host->wq, &wait);
if (card != (void *)-1) {
err = mmc_select_card(host, card);
if (err != MMC_ERR_NONE)
return err;
}
return err;
}
EXPORT_SYMBOL(__mmc_claim_host);
/**
* mmc_release_host - release a host
* @host: mmc host to release
*
* Release a MMC host, allowing others to claim the host
* for their operations.
*/
void mmc_release_host(struct mmc_host *host)
{
unsigned long flags;
BUG_ON(!host->claimed);
spin_lock_irqsave(&host->lock, flags);
host->claimed = 0;
spin_unlock_irqrestore(&host->lock, flags);
wake_up(&host->wq);
}
EXPORT_SYMBOL(mmc_release_host);
static inline void mmc_set_ios(struct mmc_host *host)
{
struct mmc_ios *ios = &host->ios;
pr_debug("%s: clock %uHz busmode %u powermode %u cs %u Vdd %u width %u\n",
mmc_hostname(host), ios->clock, ios->bus_mode,
ios->power_mode, ios->chip_select, ios->vdd,
ios->bus_width);
host->ops->set_ios(host, ios);
}
static int mmc_select_card(struct mmc_host *host, struct mmc_card *card)
{
int err;
struct mmc_command cmd;
BUG_ON(!host->claimed);
if (host->card_selected == card)
return MMC_ERR_NONE;
host->card_selected = card;
cmd.opcode = MMC_SELECT_CARD;
cmd.arg = card->rca << 16;
cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
if (err != MMC_ERR_NONE)
return err;
/*
* We can only change the bus width of SD cards when
* they are selected so we have to put the handling
* here.
*
* The card is in 1 bit mode by default so
* we only need to change if it supports the
* wider version.
*/
if (mmc_card_sd(card) &&
(card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) {
/*
* Default bus width is 1 bit.
*/
host->ios.bus_width = MMC_BUS_WIDTH_1;
if (host->caps & MMC_CAP_4_BIT_DATA) {
struct mmc_command cmd;
cmd.opcode = SD_APP_SET_BUS_WIDTH;
cmd.arg = SD_BUS_WIDTH_4;
cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
err = mmc_wait_for_app_cmd(host, card->rca, &cmd,
CMD_RETRIES);
if (err != MMC_ERR_NONE)
return err;
host->ios.bus_width = MMC_BUS_WIDTH_4;
}
}
mmc_set_ios(host);
return MMC_ERR_NONE;
}
/*
* Ensure that no card is selected.
*/
static void mmc_deselect_cards(struct mmc_host *host)
{
struct mmc_command cmd;
if (host->card_selected) {
host->card_selected = NULL;
cmd.opcode = MMC_SELECT_CARD;
cmd.arg = 0;
cmd.flags = MMC_RSP_NONE | MMC_CMD_AC;
mmc_wait_for_cmd(host, &cmd, 0);
}
}
static inline void mmc_delay(unsigned int ms)
{
if (ms < 1000 / HZ) {
cond_resched();
mdelay(ms);
} else {
msleep(ms);
}
}
/*
* Mask off any voltages we don't support and select
* the lowest voltage
*/
static u32 mmc_select_voltage(struct mmc_host *host, u32 ocr)
{
int bit;
ocr &= host->ocr_avail;
bit = ffs(ocr);
if (bit) {
bit -= 1;
ocr &= 3 << bit;
host->ios.vdd = bit;
mmc_set_ios(host);
} else {
ocr = 0;
}
return ocr;
}
#define UNSTUFF_BITS(resp,start,size) \
({ \
const int __size = size; \
const u32 __mask = (__size < 32 ? 1 << __size : 0) - 1; \
const int __off = 3 - ((start) / 32); \
const int __shft = (start) & 31; \
u32 __res; \
\
__res = resp[__off] >> __shft; \
if (__size + __shft > 32) \
__res |= resp[__off-1] << ((32 - __shft) % 32); \
__res & __mask; \
})
/*
* Given the decoded CSD structure, decode the raw CID to our CID structure.
*/
static void mmc_decode_cid(struct mmc_card *card)
{
u32 *resp = card->raw_cid;
memset(&card->cid, 0, sizeof(struct mmc_cid));
if (mmc_card_sd(card)) {
/*
* SD doesn't currently have a version field so we will
* have to assume we can parse this.
*/
card->cid.manfid = UNSTUFF_BITS(resp, 120, 8);
card->cid.oemid = UNSTUFF_BITS(resp, 104, 16);
card->cid.prod_name[0] = UNSTUFF_BITS(resp, 96, 8);
card->cid.prod_name[1] = UNSTUFF_BITS(resp, 88, 8);
card->cid.prod_name[2] = UNSTUFF_BITS(resp, 80, 8);
card->cid.prod_name[3] = UNSTUFF_BITS(resp, 72, 8);
card->cid.prod_name[4] = UNSTUFF_BITS(resp, 64, 8);
card->cid.hwrev = UNSTUFF_BITS(resp, 60, 4);
card->cid.fwrev = UNSTUFF_BITS(resp, 56, 4);
card->cid.serial = UNSTUFF_BITS(resp, 24, 32);
card->cid.year = UNSTUFF_BITS(resp, 12, 8);
card->cid.month = UNSTUFF_BITS(resp, 8, 4);
card->cid.year += 2000; /* SD cards year offset */
} else {
/*
* The selection of the format here is based upon published
* specs from sandisk and from what people have reported.
*/
switch (card->csd.mmca_vsn) {
case 0: /* MMC v1.0 - v1.2 */
case 1: /* MMC v1.4 */
card->cid.manfid = UNSTUFF_BITS(resp, 104, 24);
card->cid.prod_name[0] = UNSTUFF_BITS(resp, 96, 8);
card->cid.prod_name[1] = UNSTUFF_BITS(resp, 88, 8);
card->cid.prod_name[2] = UNSTUFF_BITS(resp, 80, 8);
card->cid.prod_name[3] = UNSTUFF_BITS(resp, 72, 8);
card->cid.prod_name[4] = UNSTUFF_BITS(resp, 64, 8);
card->cid.prod_name[5] = UNSTUFF_BITS(resp, 56, 8);
card->cid.prod_name[6] = UNSTUFF_BITS(resp, 48, 8);
card->cid.hwrev = UNSTUFF_BITS(resp, 44, 4);
card->cid.fwrev = UNSTUFF_BITS(resp, 40, 4);
card->cid.serial = UNSTUFF_BITS(resp, 16, 24);
card->cid.month = UNSTUFF_BITS(resp, 12, 4);
card->cid.year = UNSTUFF_BITS(resp, 8, 4) + 1997;
break;
case 2: /* MMC v2.0 - v2.2 */
case 3: /* MMC v3.1 - v3.3 */
case 4: /* MMC v4 */
card->cid.manfid = UNSTUFF_BITS(resp, 120, 8);
card->cid.oemid = UNSTUFF_BITS(resp, 104, 16);
card->cid.prod_name[0] = UNSTUFF_BITS(resp, 96, 8);
card->cid.prod_name[1] = UNSTUFF_BITS(resp, 88, 8);
card->cid.prod_name[2] = UNSTUFF_BITS(resp, 80, 8);
card->cid.prod_name[3] = UNSTUFF_BITS(resp, 72, 8);
card->cid.prod_name[4] = UNSTUFF_BITS(resp, 64, 8);
card->cid.prod_name[5] = UNSTUFF_BITS(resp, 56, 8);
card->cid.serial = UNSTUFF_BITS(resp, 16, 32);
card->cid.month = UNSTUFF_BITS(resp, 12, 4);
card->cid.year = UNSTUFF_BITS(resp, 8, 4) + 1997;
break;
default:
printk("%s: card has unknown MMCA version %d\n",
mmc_hostname(card->host), card->csd.mmca_vsn);
mmc_card_set_bad(card);
break;
}
}
}
/*
* Given a 128-bit response, decode to our card CSD structure.
*/
static void mmc_decode_csd(struct mmc_card *card)
{
struct mmc_csd *csd = &card->csd;
unsigned int e, m, csd_struct;
u32 *resp = card->raw_csd;
if (mmc_card_sd(card)) {
csd_struct = UNSTUFF_BITS(resp, 126, 2);
switch (csd_struct) {
case 0:
m = UNSTUFF_BITS(resp, 115, 4);
e = UNSTUFF_BITS(resp, 112, 3);
csd->tacc_ns = (tacc_exp[e] * tacc_mant[m] + 9) / 10;
csd->tacc_clks = UNSTUFF_BITS(resp, 104, 8) * 100;
m = UNSTUFF_BITS(resp, 99, 4);
e = UNSTUFF_BITS(resp, 96, 3);
csd->max_dtr = tran_exp[e] * tran_mant[m];
csd->cmdclass = UNSTUFF_BITS(resp, 84, 12);
e = UNSTUFF_BITS(resp, 47, 3);
m = UNSTUFF_BITS(resp, 62, 12);
csd->capacity = (1 + m) << (e + 2);
csd->read_blkbits = UNSTUFF_BITS(resp, 80, 4);
csd->read_partial = UNSTUFF_BITS(resp, 79, 1);
csd->write_misalign = UNSTUFF_BITS(resp, 78, 1);
csd->read_misalign = UNSTUFF_BITS(resp, 77, 1);
csd->r2w_factor = UNSTUFF_BITS(resp, 26, 3);
csd->write_blkbits = UNSTUFF_BITS(resp, 22, 4);
csd->write_partial = UNSTUFF_BITS(resp, 21, 1);
break;
case 1:
/*
* This is a block-addressed SDHC card. Most
* interesting fields are unused and have fixed
* values. To avoid getting tripped by buggy cards,
* we assume those fixed values ourselves.
*/
mmc_card_set_blockaddr(card);
csd->tacc_ns = 0; /* Unused */
csd->tacc_clks = 0; /* Unused */
m = UNSTUFF_BITS(resp, 99, 4);
e = UNSTUFF_BITS(resp, 96, 3);
csd->max_dtr = tran_exp[e] * tran_mant[m];
csd->cmdclass = UNSTUFF_BITS(resp, 84, 12);
m = UNSTUFF_BITS(resp, 48, 22);
csd->capacity = (1 + m) << 10;
csd->read_blkbits = 9;
csd->read_partial = 0;
csd->write_misalign = 0;
csd->read_misalign = 0;
csd->r2w_factor = 4; /* Unused */
csd->write_blkbits = 9;
csd->write_partial = 0;
break;
default:
printk("%s: unrecognised CSD structure version %d\n",
mmc_hostname(card->host), csd_struct);
mmc_card_set_bad(card);
return;
}
} else {
/*
* We only understand CSD structure v1.1 and v1.2.
* v1.2 has extra information in bits 15, 11 and 10.
*/
csd_struct = UNSTUFF_BITS(resp, 126, 2);
if (csd_struct != 1 && csd_struct != 2) {
printk("%s: unrecognised CSD structure version %d\n",
mmc_hostname(card->host), csd_struct);
mmc_card_set_bad(card);
return;
}
csd->mmca_vsn = UNSTUFF_BITS(resp, 122, 4);
m = UNSTUFF_BITS(resp, 115, 4);
e = UNSTUFF_BITS(resp, 112, 3);
csd->tacc_ns = (tacc_exp[e] * tacc_mant[m] + 9) / 10;
csd->tacc_clks = UNSTUFF_BITS(resp, 104, 8) * 100;
m = UNSTUFF_BITS(resp, 99, 4);
e = UNSTUFF_BITS(resp, 96, 3);
csd->max_dtr = tran_exp[e] * tran_mant[m];
csd->cmdclass = UNSTUFF_BITS(resp, 84, 12);
e = UNSTUFF_BITS(resp, 47, 3);
m = UNSTUFF_BITS(resp, 62, 12);
csd->capacity = (1 + m) << (e + 2);
csd->read_blkbits = UNSTUFF_BITS(resp, 80, 4);
csd->read_partial = UNSTUFF_BITS(resp, 79, 1);
csd->write_misalign = UNSTUFF_BITS(resp, 78, 1);
csd->read_misalign = UNSTUFF_BITS(resp, 77, 1);
csd->r2w_factor = UNSTUFF_BITS(resp, 26, 3);
csd->write_blkbits = UNSTUFF_BITS(resp, 22, 4);
csd->write_partial = UNSTUFF_BITS(resp, 21, 1);
}
}
/*
* Given a 64-bit response, decode to our card SCR structure.
*/
static void mmc_decode_scr(struct mmc_card *card)
{
struct sd_scr *scr = &card->scr;
unsigned int scr_struct;
u32 resp[4];
BUG_ON(!mmc_card_sd(card));
resp[3] = card->raw_scr[1];
resp[2] = card->raw_scr[0];
scr_struct = UNSTUFF_BITS(resp, 60, 4);
if (scr_struct != 0) {
printk("%s: unrecognised SCR structure version %d\n",
mmc_hostname(card->host), scr_struct);
mmc_card_set_bad(card);
return;
}
scr->sda_vsn = UNSTUFF_BITS(resp, 56, 4);
scr->bus_widths = UNSTUFF_BITS(resp, 48, 4);
}
/*
* Locate a MMC card on this MMC host given a raw CID.
*/
static struct mmc_card *mmc_find_card(struct mmc_host *host, u32 *raw_cid)
{
struct mmc_card *card;
list_for_each_entry(card, &host->cards, node) {
if (memcmp(card->raw_cid, raw_cid, sizeof(card->raw_cid)) == 0)
return card;
}
return NULL;
}
/*
* Allocate a new MMC card, and assign a unique RCA.
*/
static struct mmc_card *
mmc_alloc_card(struct mmc_host *host, u32 *raw_cid, unsigned int *frca)
{
struct mmc_card *card, *c;
unsigned int rca = *frca;
card = kmalloc(sizeof(struct mmc_card), GFP_KERNEL);
if (!card)
return ERR_PTR(-ENOMEM);
mmc_init_card(card, host);
memcpy(card->raw_cid, raw_cid, sizeof(card->raw_cid));
again:
list_for_each_entry(c, &host->cards, node)
if (c->rca == rca) {
rca++;
goto again;
}
card->rca = rca;
*frca = rca;
return card;
}
/*
* Tell attached cards to go to IDLE state
*/
static void mmc_idle_cards(struct mmc_host *host)
{
struct mmc_command cmd;
host->ios.chip_select = MMC_CS_HIGH;
mmc_set_ios(host);
mmc_delay(1);
cmd.opcode = MMC_GO_IDLE_STATE;
cmd.arg = 0;
cmd.flags = MMC_RSP_NONE | MMC_CMD_BC;
mmc_wait_for_cmd(host, &cmd, 0);
mmc_delay(1);
host->ios.chip_select = MMC_CS_DONTCARE;
mmc_set_ios(host);
mmc_delay(1);
}
/*
* Apply power to the MMC stack. This is a two-stage process.
* First, we enable power to the card without the clock running.
* We then wait a bit for the power to stabilise. Finally,
* enable the bus drivers and clock to the card.
*
* We must _NOT_ enable the clock prior to power stablising.
*
* If a host does all the power sequencing itself, ignore the
* initial MMC_POWER_UP stage.
*/
static void mmc_power_up(struct mmc_host *host)
{
int bit = fls(host->ocr_avail) - 1;
host->ios.vdd = bit;
host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
host->ios.chip_select = MMC_CS_DONTCARE;
host->ios.power_mode = MMC_POWER_UP;
host->ios.bus_width = MMC_BUS_WIDTH_1;
mmc_set_ios(host);
mmc_delay(1);
host->ios.clock = host->f_min;
host->ios.power_mode = MMC_POWER_ON;
mmc_set_ios(host);
mmc_delay(2);
}
static void mmc_power_off(struct mmc_host *host)
{
host->ios.clock = 0;
host->ios.vdd = 0;
host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
host->ios.chip_select = MMC_CS_DONTCARE;
host->ios.power_mode = MMC_POWER_OFF;
host->ios.bus_width = MMC_BUS_WIDTH_1;
mmc_set_ios(host);
}
static int mmc_send_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr)
{
struct mmc_command cmd;
int i, err = 0;
cmd.opcode = MMC_SEND_OP_COND;
cmd.arg = ocr;
cmd.flags = MMC_RSP_R3 | MMC_CMD_BCR;
for (i = 100; i; i--) {
err = mmc_wait_for_cmd(host, &cmd, 0);
if (err != MMC_ERR_NONE)
break;
if (cmd.resp[0] & MMC_CARD_BUSY || ocr == 0)
break;
err = MMC_ERR_TIMEOUT;
mmc_delay(10);
}
if (rocr)
*rocr = cmd.resp[0];
return err;
}
static int mmc_send_app_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr)
{
struct mmc_command cmd;
int i, err = 0;
cmd.opcode = SD_APP_OP_COND;
cmd.arg = ocr;
cmd.flags = MMC_RSP_R3 | MMC_CMD_BCR;
for (i = 100; i; i--) {
err = mmc_wait_for_app_cmd(host, 0, &cmd, CMD_RETRIES);
if (err != MMC_ERR_NONE)
break;
if (cmd.resp[0] & MMC_CARD_BUSY || ocr == 0)
break;
err = MMC_ERR_TIMEOUT;
mmc_delay(10);
}
if (rocr)
*rocr = cmd.resp[0];
return err;
}
static int mmc_send_if_cond(struct mmc_host *host, u32 ocr, int *rsd2)
{
struct mmc_command cmd;
int err, sd2;
static const u8 test_pattern = 0xAA;
/*
* To support SD 2.0 cards, we must always invoke SD_SEND_IF_COND
* before SD_APP_OP_COND. This command will harmlessly fail for
* SD 1.0 cards.
*/
cmd.opcode = SD_SEND_IF_COND;
cmd.arg = ((ocr & 0xFF8000) != 0) << 8 | test_pattern;
cmd.flags = MMC_RSP_R7 | MMC_CMD_BCR;
err = mmc_wait_for_cmd(host, &cmd, 0);
if (err == MMC_ERR_NONE) {
if ((cmd.resp[0] & 0xFF) == test_pattern) {
sd2 = 1;
} else {
sd2 = 0;
err = MMC_ERR_FAILED;
}
} else {
/*
* Treat errors as SD 1.0 card.
*/
sd2 = 0;
err = MMC_ERR_NONE;
}
if (rsd2)
*rsd2 = sd2;
return err;
}
/*
* Discover cards by requesting their CID. If this command
* times out, it is not an error; there are no further cards
* to be discovered. Add new cards to the list.
*
* Create a mmc_card entry for each discovered card, assigning
* it an RCA, and save the raw CID for decoding later.
*/
static void mmc_discover_cards(struct mmc_host *host)
{
struct mmc_card *card;
unsigned int first_rca = 1, err;
while (1) {
struct mmc_command cmd;
cmd.opcode = MMC_ALL_SEND_CID;
cmd.arg = 0;
cmd.flags = MMC_RSP_R2 | MMC_CMD_BCR;
err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
if (err == MMC_ERR_TIMEOUT) {
err = MMC_ERR_NONE;
break;
}
if (err != MMC_ERR_NONE) {
printk(KERN_ERR "%s: error requesting CID: %d\n",
mmc_hostname(host), err);
break;
}
card = mmc_find_card(host, cmd.resp);
if (!card) {
card = mmc_alloc_card(host, cmd.resp, &first_rca);
if (IS_ERR(card)) {
err = PTR_ERR(card);
break;
}
list_add(&card->node, &host->cards);
}
card->state &= ~MMC_STATE_DEAD;
if (host->mode == MMC_MODE_SD) {
mmc_card_set_sd(card);
cmd.opcode = SD_SEND_RELATIVE_ADDR;
cmd.arg = 0;
cmd.flags = MMC_RSP_R6 | MMC_CMD_BCR;
err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
if (err != MMC_ERR_NONE)
mmc_card_set_dead(card);
else {
card->rca = cmd.resp[0] >> 16;
if (!host->ops->get_ro) {
printk(KERN_WARNING "%s: host does not "
"support reading read-only "
"switch. assuming write-enable.\n",
mmc_hostname(host));
} else {
if (host->ops->get_ro(host))
mmc_card_set_readonly(card);
}
}
} else {
cmd.opcode = MMC_SET_RELATIVE_ADDR;
cmd.arg = card->rca << 16;
cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
if (err != MMC_ERR_NONE)
mmc_card_set_dead(card);
}
}
}
static void mmc_read_csds(struct mmc_host *host)
{
struct mmc_card *card;
list_for_each_entry(card, &host->cards, node) {
struct mmc_command cmd;
int err;
if (card->state & (MMC_STATE_DEAD|MMC_STATE_PRESENT))
continue;
cmd.opcode = MMC_SEND_CSD;
cmd.arg = card->rca << 16;
cmd.flags = MMC_RSP_R2 | MMC_CMD_AC;
err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
if (err != MMC_ERR_NONE) {
mmc_card_set_dead(card);
continue;
}
memcpy(card->raw_csd, cmd.resp, sizeof(card->raw_csd));
mmc_decode_csd(card);
mmc_decode_cid(card);
}
}
static void mmc_process_ext_csds(struct mmc_host *host)
{
int err;
struct mmc_card *card;
struct mmc_request mrq;
struct mmc_command cmd;
struct mmc_data data;
struct scatterlist sg;
/*
* As the ext_csd is so large and mostly unused, we don't store the
* raw block in mmc_card.
*/
u8 *ext_csd;
ext_csd = kmalloc(512, GFP_KERNEL);
if (!ext_csd) {
printk("%s: could not allocate a buffer to receive the ext_csd."
"mmc v4 cards will be treated as v3.\n",
mmc_hostname(host));
return;
}
list_for_each_entry(card, &host->cards, node) {
if (card->state & (MMC_STATE_DEAD|MMC_STATE_PRESENT))
continue;
if (mmc_card_sd(card))
continue;
if (card->csd.mmca_vsn < CSD_SPEC_VER_4)
continue;
err = mmc_select_card(host, card);
if (err != MMC_ERR_NONE) {
mmc_card_set_dead(card);
continue;
}
memset(&cmd, 0, sizeof(struct mmc_command));
cmd.opcode = MMC_SEND_EXT_CSD;
cmd.arg = 0;
cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
memset(&data, 0, sizeof(struct mmc_data));
mmc_set_data_timeout(&data, card, 0);
data.blksz = 512;
data.blocks = 1;
data.flags = MMC_DATA_READ;
data.sg = &sg;
data.sg_len = 1;
memset(&mrq, 0, sizeof(struct mmc_request));
mrq.cmd = &cmd;
mrq.data = &data;
sg_init_one(&sg, ext_csd, 512);
mmc_wait_for_req(host, &mrq);
if (cmd.error != MMC_ERR_NONE || data.error != MMC_ERR_NONE) {
mmc_card_set_dead(card);
continue;
}
switch (ext_csd[EXT_CSD_CARD_TYPE]) {
case EXT_CSD_CARD_TYPE_52 | EXT_CSD_CARD_TYPE_26:
card->ext_csd.hs_max_dtr = 52000000;
break;
case EXT_CSD_CARD_TYPE_26:
card->ext_csd.hs_max_dtr = 26000000;
break;
default:
/* MMC v4 spec says this cannot happen */
printk("%s: card is mmc v4 but doesn't support "
"any high-speed modes.\n",
mmc_hostname(card->host));
mmc_card_set_bad(card);
continue;
}
/* Activate highspeed support. */
cmd.opcode = MMC_SWITCH;
cmd.arg = (MMC_SWITCH_MODE_WRITE_BYTE << 24) |
(EXT_CSD_HS_TIMING << 16) |
(1 << 8) |
EXT_CSD_CMD_SET_NORMAL;
cmd.flags = MMC_RSP_R1B | MMC_CMD_AC;
err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
if (err != MMC_ERR_NONE) {
printk("%s: failed to switch card to mmc v4 "
"high-speed mode.\n",
mmc_hostname(card->host));
continue;
}
mmc_card_set_highspeed(card);
/* Check for host support for wide-bus modes. */
if (!(host->caps & MMC_CAP_4_BIT_DATA)) {
continue;
}
/* Activate 4-bit support. */
cmd.opcode = MMC_SWITCH;
cmd.arg = (MMC_SWITCH_MODE_WRITE_BYTE << 24) |
(EXT_CSD_BUS_WIDTH << 16) |
(EXT_CSD_BUS_WIDTH_4 << 8) |
EXT_CSD_CMD_SET_NORMAL;
cmd.flags = MMC_RSP_R1B | MMC_CMD_AC;
err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
if (err != MMC_ERR_NONE) {
printk("%s: failed to switch card to "
"mmc v4 4-bit bus mode.\n",
mmc_hostname(card->host));
continue;
}
host->ios.bus_width = MMC_BUS_WIDTH_4;
}
kfree(ext_csd);
mmc_deselect_cards(host);
}
static void mmc_read_scrs(struct mmc_host *host)
{
int err;
struct mmc_card *card;
struct mmc_request mrq;
struct mmc_command cmd;
struct mmc_data data;
struct scatterlist sg;
list_for_each_entry(card, &host->cards, node) {
if (card->state & (MMC_STATE_DEAD|MMC_STATE_PRESENT))
continue;
if (!mmc_card_sd(card))
continue;
err = mmc_select_card(host, card);
if (err != MMC_ERR_NONE) {
mmc_card_set_dead(card);
continue;
}
memset(&cmd, 0, sizeof(struct mmc_command));
cmd.opcode = MMC_APP_CMD;
cmd.arg = card->rca << 16;
cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
err = mmc_wait_for_cmd(host, &cmd, 0);
if ((err != MMC_ERR_NONE) || !(cmd.resp[0] & R1_APP_CMD)) {
mmc_card_set_dead(card);
continue;
}
memset(&cmd, 0, sizeof(struct mmc_command));
cmd.opcode = SD_APP_SEND_SCR;
cmd.arg = 0;
cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
memset(&data, 0, sizeof(struct mmc_data));
mmc_set_data_timeout(&data, card, 0);
data.blksz = 1 << 3;
data.blocks = 1;
data.flags = MMC_DATA_READ;
data.sg = &sg;
data.sg_len = 1;
memset(&mrq, 0, sizeof(struct mmc_request));
mrq.cmd = &cmd;
mrq.data = &data;
sg_init_one(&sg, (u8*)card->raw_scr, 8);
mmc_wait_for_req(host, &mrq);
if (cmd.error != MMC_ERR_NONE || data.error != MMC_ERR_NONE) {
mmc_card_set_dead(card);
continue;
}
card->raw_scr[0] = ntohl(card->raw_scr[0]);
card->raw_scr[1] = ntohl(card->raw_scr[1]);
mmc_decode_scr(card);
}
mmc_deselect_cards(host);
}
static void mmc_read_switch_caps(struct mmc_host *host)
{
int err;
struct mmc_card *card;
struct mmc_request mrq;
struct mmc_command cmd;
struct mmc_data data;
unsigned char *status;
struct scatterlist sg;
status = kmalloc(64, GFP_KERNEL);
if (!status) {
printk(KERN_WARNING "%s: Unable to allocate buffer for "
"reading switch capabilities.\n",
mmc_hostname(host));
return;
}
list_for_each_entry(card, &host->cards, node) {
if (card->state & (MMC_STATE_DEAD|MMC_STATE_PRESENT))
continue;
if (!mmc_card_sd(card))
continue;
if (card->scr.sda_vsn < SCR_SPEC_VER_1)
continue;
err = mmc_select_card(host, card);
if (err != MMC_ERR_NONE) {
mmc_card_set_dead(card);
continue;
}
memset(&cmd, 0, sizeof(struct mmc_command));
cmd.opcode = SD_SWITCH;
cmd.arg = 0x00FFFFF1;
cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
memset(&data, 0, sizeof(struct mmc_data));
mmc_set_data_timeout(&data, card, 0);
data.blksz = 64;
data.blocks = 1;
data.flags = MMC_DATA_READ;
data.sg = &sg;
data.sg_len = 1;
memset(&mrq, 0, sizeof(struct mmc_request));
mrq.cmd = &cmd;
mrq.data = &data;
sg_init_one(&sg, status, 64);
mmc_wait_for_req(host, &mrq);
if (cmd.error != MMC_ERR_NONE || data.error != MMC_ERR_NONE) {
mmc_card_set_dead(card);
continue;
}
if (status[13] & 0x02)
card->sw_caps.hs_max_dtr = 50000000;
memset(&cmd, 0, sizeof(struct mmc_command));
cmd.opcode = SD_SWITCH;
cmd.arg = 0x80FFFFF1;
cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
memset(&data, 0, sizeof(struct mmc_data));
mmc_set_data_timeout(&data, card, 0);
data.blksz = 64;
data.blocks = 1;
data.flags = MMC_DATA_READ;
data.sg = &sg;
data.sg_len = 1;
memset(&mrq, 0, sizeof(struct mmc_request));
mrq.cmd = &cmd;
mrq.data = &data;
sg_init_one(&sg, status, 64);
mmc_wait_for_req(host, &mrq);
if (cmd.error != MMC_ERR_NONE || data.error != MMC_ERR_NONE) {
mmc_card_set_dead(card);
continue;
}
if ((status[16] & 0xF) != 1) {
printk(KERN_WARNING "%s: Problem switching card "
"into high-speed mode!\n",
mmc_hostname(host));
continue;
}
mmc_card_set_highspeed(card);
}
kfree(status);
mmc_deselect_cards(host);
}
static unsigned int mmc_calculate_clock(struct mmc_host *host)
{
struct mmc_card *card;
unsigned int max_dtr = host->f_max;
list_for_each_entry(card, &host->cards, node)
if (!mmc_card_dead(card)) {
if (mmc_card_highspeed(card) && mmc_card_sd(card)) {
if (max_dtr > card->sw_caps.hs_max_dtr)
max_dtr = card->sw_caps.hs_max_dtr;
} else if (mmc_card_highspeed(card) && !mmc_card_sd(card)) {
if (max_dtr > card->ext_csd.hs_max_dtr)
max_dtr = card->ext_csd.hs_max_dtr;
} else if (max_dtr > card->csd.max_dtr) {
max_dtr = card->csd.max_dtr;
}
}
pr_debug("%s: selected %d.%03dMHz transfer rate\n",
mmc_hostname(host),
max_dtr / 1000000, (max_dtr / 1000) % 1000);
return max_dtr;
}
/*
* Check whether cards we already know about are still present.
* We do this by requesting status, and checking whether a card
* responds.
*
* A request for status does not cause a state change in data
* transfer mode.
*/
static void mmc_check_cards(struct mmc_host *host)
{
struct list_head *l, *n;
mmc_deselect_cards(host);
list_for_each_safe(l, n, &host->cards) {
struct mmc_card *card = mmc_list_to_card(l);
struct mmc_command cmd;
int err;
cmd.opcode = MMC_SEND_STATUS;
cmd.arg = card->rca << 16;
cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
if (err == MMC_ERR_NONE)
continue;
mmc_card_set_dead(card);
}
}
static void mmc_setup(struct mmc_host *host)
{
if (host->ios.power_mode != MMC_POWER_ON) {
int err;
u32 ocr;
host->mode = MMC_MODE_SD;
mmc_power_up(host);
mmc_idle_cards(host);
err = mmc_send_if_cond(host, host->ocr_avail, NULL);
if (err != MMC_ERR_NONE) {
return;
}
err = mmc_send_app_op_cond(host, 0, &ocr);
/*
* If we fail to detect any SD cards then try
* searching for MMC cards.
*/
if (err != MMC_ERR_NONE) {
host->mode = MMC_MODE_MMC;
err = mmc_send_op_cond(host, 0, &ocr);
if (err != MMC_ERR_NONE)
return;
}
host->ocr = mmc_select_voltage(host, ocr);
/*
* Since we're changing the OCR value, we seem to
* need to tell some cards to go back to the idle
* state. We wait 1ms to give cards time to
* respond.
*/
if (host->ocr)
mmc_idle_cards(host);
} else {
host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
host->ios.clock = host->f_min;
mmc_set_ios(host);
/*
* We should remember the OCR mask from the existing
* cards, and detect the new cards OCR mask, combine
* the two and re-select the VDD. However, if we do
* change VDD, we should do an idle, and then do a
* full re-initialisation. We would need to notify
* drivers so that they can re-setup the cards as
* well, while keeping their queues at bay.
*
* For the moment, we take the easy way out - if the
* new cards don't like our currently selected VDD,
* they drop off the bus.
*/
}
if (host->ocr == 0)
return;
/*
* Send the selected OCR multiple times... until the cards
* all get the idea that they should be ready for CMD2.
* (My SanDisk card seems to need this.)
*/
if (host->mode == MMC_MODE_SD) {
int err, sd2;
err = mmc_send_if_cond(host, host->ocr, &sd2);
if (err == MMC_ERR_NONE) {
/*
* If SD_SEND_IF_COND indicates an SD 2.0
* compliant card and we should set bit 30
* of the ocr to indicate that we can handle
* block-addressed SDHC cards.
*/
mmc_send_app_op_cond(host, host->ocr | (sd2 << 30), NULL);
}
} else {
mmc_send_op_cond(host, host->ocr, NULL);
}
mmc_discover_cards(host);
/*
* Ok, now switch to push-pull mode.
*/
host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
mmc_set_ios(host);
mmc_read_csds(host);
if (host->mode == MMC_MODE_SD) {
mmc_read_scrs(host);
mmc_read_switch_caps(host);
} else
mmc_process_ext_csds(host);
}
/**
* mmc_detect_change - process change of state on a MMC socket
* @host: host which changed state.
* @delay: optional delay to wait before detection (jiffies)
*
* All we know is that card(s) have been inserted or removed
* from the socket(s). We don't know which socket or cards.
*/
void mmc_detect_change(struct mmc_host *host, unsigned long delay)
{
mmc_schedule_delayed_work(&host->detect, delay);
}
EXPORT_SYMBOL(mmc_detect_change);
static void mmc_rescan(struct work_struct *work)
{
struct mmc_host *host =
container_of(work, struct mmc_host, detect.work);
struct list_head *l, *n;
unsigned char power_mode;
mmc_claim_host(host);
/*
* Check for removed cards and newly inserted ones. We check for
* removed cards first so we can intelligently re-select the VDD.
*/
power_mode = host->ios.power_mode;
if (power_mode == MMC_POWER_ON)
mmc_check_cards(host);
mmc_setup(host);
/*
* Some broken cards process CMD1 even in stand-by state. There is
* no reply, but an ILLEGAL_COMMAND error is cached and returned
* after next command. We poll for card status here to clear any
* possibly pending error.
*/
if (power_mode == MMC_POWER_ON)
mmc_check_cards(host);
if (!list_empty(&host->cards)) {
/*
* (Re-)calculate the fastest clock rate which the
* attached cards and the host support.
*/
host->ios.clock = mmc_calculate_clock(host);
mmc_set_ios(host);
}
mmc_release_host(host);
list_for_each_safe(l, n, &host->cards) {
struct mmc_card *card = mmc_list_to_card(l);
/*
* If this is a new and good card, register it.
*/
if (!mmc_card_present(card) && !mmc_card_dead(card)) {
if (mmc_register_card(card))
mmc_card_set_dead(card);
else
mmc_card_set_present(card);
}
/*
* If this card is dead, destroy it.
*/
if (mmc_card_dead(card)) {
list_del(&card->node);
mmc_remove_card(card);
}
}
/*
* If we discover that there are no cards on the
* bus, turn off the clock and power down.
*/
if (list_empty(&host->cards))
mmc_power_off(host);
}
/**
* mmc_alloc_host - initialise the per-host structure.
* @extra: sizeof private data structure
* @dev: pointer to host device model structure
*
* Initialise the per-host structure.
*/
struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
{
struct mmc_host *host;
host = mmc_alloc_host_sysfs(extra, dev);
if (host) {
spin_lock_init(&host->lock);
init_waitqueue_head(&host->wq);
INIT_LIST_HEAD(&host->cards);
INIT_DELAYED_WORK(&host->detect, mmc_rescan);
/*
* By default, hosts do not support SGIO or large requests.
* They have to set these according to their abilities.
*/
host->max_hw_segs = 1;
host->max_phys_segs = 1;
host->max_sectors = 1 << (PAGE_CACHE_SHIFT - 9);
host->max_seg_size = PAGE_CACHE_SIZE;
}
return host;
}
EXPORT_SYMBOL(mmc_alloc_host);
/**
* mmc_add_host - initialise host hardware
* @host: mmc host
*/
int mmc_add_host(struct mmc_host *host)
{
int ret;
ret = mmc_add_host_sysfs(host);
if (ret == 0) {
mmc_power_off(host);
mmc_detect_change(host, 0);
}
return ret;
}
EXPORT_SYMBOL(mmc_add_host);
/**
* mmc_remove_host - remove host hardware
* @host: mmc host
*
* Unregister and remove all cards associated with this host,
* and power down the MMC bus.
*/
void mmc_remove_host(struct mmc_host *host)
{
struct list_head *l, *n;
list_for_each_safe(l, n, &host->cards) {
struct mmc_card *card = mmc_list_to_card(l);
mmc_remove_card(card);
}
mmc_power_off(host);
mmc_remove_host_sysfs(host);
}
EXPORT_SYMBOL(mmc_remove_host);
/**
* mmc_free_host - free the host structure
* @host: mmc host
*
* Free the host once all references to it have been dropped.
*/
void mmc_free_host(struct mmc_host *host)
{
mmc_flush_scheduled_work();
mmc_free_host_sysfs(host);
}
EXPORT_SYMBOL(mmc_free_host);
#ifdef CONFIG_PM
/**
* mmc_suspend_host - suspend a host
* @host: mmc host
* @state: suspend mode (PM_SUSPEND_xxx)
*/
int mmc_suspend_host(struct mmc_host *host, pm_message_t state)
{
mmc_claim_host(host);
mmc_deselect_cards(host);
mmc_power_off(host);
mmc_release_host(host);
return 0;
}
EXPORT_SYMBOL(mmc_suspend_host);
/**
* mmc_resume_host - resume a previously suspended host
* @host: mmc host
*/
int mmc_resume_host(struct mmc_host *host)
{
mmc_rescan(&host->detect.work);
return 0;
}
EXPORT_SYMBOL(mmc_resume_host);
#endif
MODULE_LICENSE("GPL");