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linux/drivers/mmc/core/sd.c
Adrian Hunter dfe86cba76 mmc: add erase, secure erase, trim and secure trim operations 
SD/MMC cards tend to support an erase operation.  In addition, eMMC v4.4
cards can support secure erase, trim and secure trim operations that are
all variants of the basic erase command.

SD/MMC device attributes "erase_size" and "preferred_erase_size" have been
added.

"erase_size" is the minimum size, in bytes, of an erase operation.  For
MMC, "erase_size" is the erase group size reported by the card.  Note that
"erase_size" does not apply to trim or secure trim operations where the
minimum size is always one 512 byte sector.  For SD, "erase_size" is 512
if the card is block-addressed, 0 otherwise.

SD/MMC cards can erase an arbitrarily large area up to and
including the whole card.  When erasing a large area it may
be desirable to do it in smaller chunks for three reasons:

    1. A single erase command will make all other I/O on the card
       wait.  This is not a problem if the whole card is being erased, but
       erasing one partition will make I/O for another partition on the
       same card wait for the duration of the erase - which could be a
       several minutes.

    2. To be able to inform the user of erase progress.

    3. The erase timeout becomes too large to be very useful.
       Because the erase timeout contains a margin which is multiplied by
       the size of the erase area, the value can end up being several
       minutes for large areas.

"erase_size" is not the most efficient unit to erase (especially for SD
where it is just one sector), hence "preferred_erase_size" provides a good
chunk size for erasing large areas.

For MMC, "preferred_erase_size" is the high-capacity erase size if a card
specifies one, otherwise it is based on the capacity of the card.

For SD, "preferred_erase_size" is the allocation unit size specified by
the card.

"preferred_erase_size" is in bytes.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Cc: Kyungmin Park <kmpark@infradead.org>
Cc: Madhusudhan Chikkature <madhu.cr@ti.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ben Gardiner <bengardiner@nanometrics.ca>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-12 08:43:30 -07:00

840 lines
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/*
* linux/drivers/mmc/core/sd.c
*
* Copyright (C) 2003-2004 Russell King, All Rights Reserved.
* SD support Copyright (C) 2004 Ian Molton, All Rights Reserved.
* Copyright (C) 2005-2007 Pierre Ossman, 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/err.h>
#include <linux/slab.h>
#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
#include <linux/mmc/mmc.h>
#include <linux/mmc/sd.h>
#include "core.h"
#include "bus.h"
#include "mmc_ops.h"
#include "sd_ops.h"
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,
};
#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.
*/
void mmc_decode_cid(struct mmc_card *card)
{
u32 *resp = card->raw_cid;
memset(&card->cid, 0, sizeof(struct mmc_cid));
/*
* 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 */
}
/*
* Given a 128-bit response, decode to our card CSD structure.
*/
static int mmc_decode_csd(struct mmc_card *card)
{
struct mmc_csd *csd = &card->csd;
unsigned int e, m, csd_struct;
u32 *resp = card->raw_csd;
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);
if (UNSTUFF_BITS(resp, 46, 1)) {
csd->erase_size = 1;
} else if (csd->write_blkbits >= 9) {
csd->erase_size = UNSTUFF_BITS(resp, 39, 7) + 1;
csd->erase_size <<= csd->write_blkbits - 9;
}
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;
csd->erase_size = 1;
break;
default:
printk(KERN_ERR "%s: unrecognised CSD structure version %d\n",
mmc_hostname(card->host), csd_struct);
return -EINVAL;
}
card->erase_size = csd->erase_size;
return 0;
}
/*
* Given a 64-bit response, decode to our card SCR structure.
*/
static int mmc_decode_scr(struct mmc_card *card)
{
struct sd_scr *scr = &card->scr;
unsigned int scr_struct;
u32 resp[4];
resp[3] = card->raw_scr[1];
resp[2] = card->raw_scr[0];
scr_struct = UNSTUFF_BITS(resp, 60, 4);
if (scr_struct != 0) {
printk(KERN_ERR "%s: unrecognised SCR structure version %d\n",
mmc_hostname(card->host), scr_struct);
return -EINVAL;
}
scr->sda_vsn = UNSTUFF_BITS(resp, 56, 4);
scr->bus_widths = UNSTUFF_BITS(resp, 48, 4);
if (UNSTUFF_BITS(resp, 55, 1))
card->erased_byte = 0xFF;
else
card->erased_byte = 0x0;
return 0;
}
/*
* Fetch and process SD Status register.
*/
static int mmc_read_ssr(struct mmc_card *card)
{
unsigned int au, es, et, eo;
int err, i;
u32 *ssr;
if (!(card->csd.cmdclass & CCC_APP_SPEC)) {
printk(KERN_WARNING "%s: card lacks mandatory SD Status "
"function.\n", mmc_hostname(card->host));
return 0;
}
ssr = kmalloc(64, GFP_KERNEL);
if (!ssr)
return -ENOMEM;
err = mmc_app_sd_status(card, ssr);
if (err) {
printk(KERN_WARNING "%s: problem reading SD Status "
"register.\n", mmc_hostname(card->host));
err = 0;
goto out;
}
for (i = 0; i < 16; i++)
ssr[i] = be32_to_cpu(ssr[i]);
/*
* UNSTUFF_BITS only works with four u32s so we have to offset the
* bitfield positions accordingly.
*/
au = UNSTUFF_BITS(ssr, 428 - 384, 4);
if (au > 0 || au <= 9) {
card->ssr.au = 1 << (au + 4);
es = UNSTUFF_BITS(ssr, 408 - 384, 16);
et = UNSTUFF_BITS(ssr, 402 - 384, 6);
eo = UNSTUFF_BITS(ssr, 400 - 384, 2);
if (es && et) {
card->ssr.erase_timeout = (et * 1000) / es;
card->ssr.erase_offset = eo * 1000;
}
} else {
printk(KERN_WARNING "%s: SD Status: Invalid Allocation Unit "
"size.\n", mmc_hostname(card->host));
}
out:
kfree(ssr);
return err;
}
/*
* Fetches and decodes switch information
*/
static int mmc_read_switch(struct mmc_card *card)
{
int err;
u8 *status;
if (card->scr.sda_vsn < SCR_SPEC_VER_1)
return 0;
if (!(card->csd.cmdclass & CCC_SWITCH)) {
printk(KERN_WARNING "%s: card lacks mandatory switch "
"function, performance might suffer.\n",
mmc_hostname(card->host));
return 0;
}
err = -EIO;
status = kmalloc(64, GFP_KERNEL);
if (!status) {
printk(KERN_ERR "%s: could not allocate a buffer for "
"switch capabilities.\n", mmc_hostname(card->host));
return -ENOMEM;
}
err = mmc_sd_switch(card, 0, 0, 1, status);
if (err) {
/* If the host or the card can't do the switch,
* fail more gracefully. */
if ((err != -EINVAL)
&& (err != -ENOSYS)
&& (err != -EFAULT))
goto out;
printk(KERN_WARNING "%s: problem reading switch "
"capabilities, performance might suffer.\n",
mmc_hostname(card->host));
err = 0;
goto out;
}
if (status[13] & 0x02)
card->sw_caps.hs_max_dtr = 50000000;
out:
kfree(status);
return err;
}
/*
* Test if the card supports high-speed mode and, if so, switch to it.
*/
int mmc_sd_switch_hs(struct mmc_card *card)
{
int err;
u8 *status;
if (card->scr.sda_vsn < SCR_SPEC_VER_1)
return 0;
if (!(card->csd.cmdclass & CCC_SWITCH))
return 0;
if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED))
return 0;
if (card->sw_caps.hs_max_dtr == 0)
return 0;
err = -EIO;
status = kmalloc(64, GFP_KERNEL);
if (!status) {
printk(KERN_ERR "%s: could not allocate a buffer for "
"switch capabilities.\n", mmc_hostname(card->host));
return -ENOMEM;
}
err = mmc_sd_switch(card, 1, 0, 1, status);
if (err)
goto out;
if ((status[16] & 0xF) != 1) {
printk(KERN_WARNING "%s: Problem switching card "
"into high-speed mode!\n",
mmc_hostname(card->host));
err = 0;
} else {
err = 1;
}
out:
kfree(status);
return err;
}
MMC_DEV_ATTR(cid, "%08x%08x%08x%08x\n", card->raw_cid[0], card->raw_cid[1],
card->raw_cid[2], card->raw_cid[3]);
MMC_DEV_ATTR(csd, "%08x%08x%08x%08x\n", card->raw_csd[0], card->raw_csd[1],
card->raw_csd[2], card->raw_csd[3]);
MMC_DEV_ATTR(scr, "%08x%08x\n", card->raw_scr[0], card->raw_scr[1]);
MMC_DEV_ATTR(date, "%02d/%04d\n", card->cid.month, card->cid.year);
MMC_DEV_ATTR(erase_size, "%u\n", card->erase_size << 9);
MMC_DEV_ATTR(preferred_erase_size, "%u\n", card->pref_erase << 9);
MMC_DEV_ATTR(fwrev, "0x%x\n", card->cid.fwrev);
MMC_DEV_ATTR(hwrev, "0x%x\n", card->cid.hwrev);
MMC_DEV_ATTR(manfid, "0x%06x\n", card->cid.manfid);
MMC_DEV_ATTR(name, "%s\n", card->cid.prod_name);
MMC_DEV_ATTR(oemid, "0x%04x\n", card->cid.oemid);
MMC_DEV_ATTR(serial, "0x%08x\n", card->cid.serial);
static struct attribute *sd_std_attrs[] = {
&dev_attr_cid.attr,
&dev_attr_csd.attr,
&dev_attr_scr.attr,
&dev_attr_date.attr,
&dev_attr_erase_size.attr,
&dev_attr_preferred_erase_size.attr,
&dev_attr_fwrev.attr,
&dev_attr_hwrev.attr,
&dev_attr_manfid.attr,
&dev_attr_name.attr,
&dev_attr_oemid.attr,
&dev_attr_serial.attr,
NULL,
};
static struct attribute_group sd_std_attr_group = {
.attrs = sd_std_attrs,
};
static const struct attribute_group *sd_attr_groups[] = {
&sd_std_attr_group,
NULL,
};
struct device_type sd_type = {
.groups = sd_attr_groups,
};
/*
* Fetch CID from card.
*/
int mmc_sd_get_cid(struct mmc_host *host, u32 ocr, u32 *cid)
{
int err;
/*
* 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.
*/
mmc_go_idle(host);
/*
* 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.
*/
err = mmc_send_if_cond(host, ocr);
if (!err)
ocr |= 1 << 30;
err = mmc_send_app_op_cond(host, ocr, NULL);
if (err)
return err;
if (mmc_host_is_spi(host))
err = mmc_send_cid(host, cid);
else
err = mmc_all_send_cid(host, cid);
return err;
}
int mmc_sd_get_csd(struct mmc_host *host, struct mmc_card *card)
{
int err;
/*
* Fetch CSD from card.
*/
err = mmc_send_csd(card, card->raw_csd);
if (err)
return err;
err = mmc_decode_csd(card);
if (err)
return err;
return 0;
}
int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card,
bool reinit)
{
int err;
if (!reinit) {
/*
* Fetch SCR from card.
*/
err = mmc_app_send_scr(card, card->raw_scr);
if (err)
return err;
err = mmc_decode_scr(card);
if (err)
return err;
/*
* Fetch and process SD Status register.
*/
err = mmc_read_ssr(card);
if (err)
return err;
/* Erase init depends on CSD and SSR */
mmc_init_erase(card);
/*
* Fetch switch information from card.
*/
err = mmc_read_switch(card);
if (err)
return err;
}
/*
* For SPI, enable CRC as appropriate.
* This CRC enable is located AFTER the reading of the
* card registers because some SDHC cards are not able
* to provide valid CRCs for non-512-byte blocks.
*/
if (mmc_host_is_spi(host)) {
err = mmc_spi_set_crc(host, use_spi_crc);
if (err)
return err;
}
/*
* Check if read-only switch is active.
*/
if (!reinit) {
int ro = -1;
if (host->ops->get_ro)
ro = host->ops->get_ro(host);
if (ro < 0) {
printk(KERN_WARNING "%s: host does not "
"support reading read-only "
"switch. assuming write-enable.\n",
mmc_hostname(host));
} else if (ro > 0) {
mmc_card_set_readonly(card);
}
}
return 0;
}
unsigned mmc_sd_get_max_clock(struct mmc_card *card)
{
unsigned max_dtr = (unsigned int)-1;
if (mmc_card_highspeed(card)) {
if (max_dtr > card->sw_caps.hs_max_dtr)
max_dtr = card->sw_caps.hs_max_dtr;
} else if (max_dtr > card->csd.max_dtr) {
max_dtr = card->csd.max_dtr;
}
return max_dtr;
}
void mmc_sd_go_highspeed(struct mmc_card *card)
{
mmc_card_set_highspeed(card);
mmc_set_timing(card->host, MMC_TIMING_SD_HS);
}
/*
* Handle the detection and initialisation of a card.
*
* In the case of a resume, "oldcard" will contain the card
* we're trying to reinitialise.
*/
static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
struct mmc_card *oldcard)
{
struct mmc_card *card;
int err;
u32 cid[4];
BUG_ON(!host);
WARN_ON(!host->claimed);
err = mmc_sd_get_cid(host, ocr, cid);
if (err)
return err;
if (oldcard) {
if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0)
return -ENOENT;
card = oldcard;
} else {
/*
* Allocate card structure.
*/
card = mmc_alloc_card(host, &sd_type);
if (IS_ERR(card))
return PTR_ERR(card);
card->type = MMC_TYPE_SD;
memcpy(card->raw_cid, cid, sizeof(card->raw_cid));
}
/*
* For native busses: get card RCA and quit open drain mode.
*/
if (!mmc_host_is_spi(host)) {
err = mmc_send_relative_addr(host, &card->rca);
if (err)
return err;
mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
}
if (!oldcard) {
err = mmc_sd_get_csd(host, card);
if (err)
return err;
mmc_decode_cid(card);
}
/*
* Select card, as all following commands rely on that.
*/
if (!mmc_host_is_spi(host)) {
err = mmc_select_card(card);
if (err)
return err;
}
err = mmc_sd_setup_card(host, card, oldcard != NULL);
if (err)
goto free_card;
/*
* Attempt to change to high-speed (if supported)
*/
err = mmc_sd_switch_hs(card);
if (err > 0)
mmc_sd_go_highspeed(card);
else if (err)
goto free_card;
/*
* Set bus speed.
*/
mmc_set_clock(host, mmc_sd_get_max_clock(card));
/*
* Switch to wider bus (if supported).
*/
if ((host->caps & MMC_CAP_4_BIT_DATA) &&
(card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) {
err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4);
if (err)
goto free_card;
mmc_set_bus_width(host, MMC_BUS_WIDTH_4);
}
host->card = card;
return 0;
free_card:
if (!oldcard)
mmc_remove_card(card);
return err;
}
/*
* Host is being removed. Free up the current card.
*/
static void mmc_sd_remove(struct mmc_host *host)
{
BUG_ON(!host);
BUG_ON(!host->card);
mmc_remove_card(host->card);
host->card = NULL;
}
/*
* Card detection callback from host.
*/
static void mmc_sd_detect(struct mmc_host *host)
{
int err;
BUG_ON(!host);
BUG_ON(!host->card);
mmc_claim_host(host);
/*
* Just check if our card has been removed.
*/
err = mmc_send_status(host->card, NULL);
mmc_release_host(host);
if (err) {
mmc_sd_remove(host);
mmc_claim_host(host);
mmc_detach_bus(host);
mmc_release_host(host);
}
}
/*
* Suspend callback from host.
*/
static int mmc_sd_suspend(struct mmc_host *host)
{
BUG_ON(!host);
BUG_ON(!host->card);
mmc_claim_host(host);
if (!mmc_host_is_spi(host))
mmc_deselect_cards(host);
host->card->state &= ~MMC_STATE_HIGHSPEED;
mmc_release_host(host);
return 0;
}
/*
* Resume callback from host.
*
* This function tries to determine if the same card is still present
* and, if so, restore all state to it.
*/
static int mmc_sd_resume(struct mmc_host *host)
{
int err;
BUG_ON(!host);
BUG_ON(!host->card);
mmc_claim_host(host);
err = mmc_sd_init_card(host, host->ocr, host->card);
mmc_release_host(host);
return err;
}
static void mmc_sd_power_restore(struct mmc_host *host)
{
host->card->state &= ~MMC_STATE_HIGHSPEED;
mmc_claim_host(host);
mmc_sd_init_card(host, host->ocr, host->card);
mmc_release_host(host);
}
static const struct mmc_bus_ops mmc_sd_ops = {
.remove = mmc_sd_remove,
.detect = mmc_sd_detect,
.suspend = NULL,
.resume = NULL,
.power_restore = mmc_sd_power_restore,
};
static const struct mmc_bus_ops mmc_sd_ops_unsafe = {
.remove = mmc_sd_remove,
.detect = mmc_sd_detect,
.suspend = mmc_sd_suspend,
.resume = mmc_sd_resume,
.power_restore = mmc_sd_power_restore,
};
static void mmc_sd_attach_bus_ops(struct mmc_host *host)
{
const struct mmc_bus_ops *bus_ops;
if (host->caps & MMC_CAP_NONREMOVABLE || !mmc_assume_removable)
bus_ops = &mmc_sd_ops_unsafe;
else
bus_ops = &mmc_sd_ops;
mmc_attach_bus(host, bus_ops);
}
/*
* Starting point for SD card init.
*/
int mmc_attach_sd(struct mmc_host *host, u32 ocr)
{
int err;
BUG_ON(!host);
WARN_ON(!host->claimed);
mmc_sd_attach_bus_ops(host);
/*
* We need to get OCR a different way for SPI.
*/
if (mmc_host_is_spi(host)) {
mmc_go_idle(host);
err = mmc_spi_read_ocr(host, 0, &ocr);
if (err)
goto err;
}
/*
* Sanity check the voltages that the card claims to
* support.
*/
if (ocr & 0x7F) {
printk(KERN_WARNING "%s: card claims to support voltages "
"below the defined range. These will be ignored.\n",
mmc_hostname(host));
ocr &= ~0x7F;
}
if (ocr & MMC_VDD_165_195) {
printk(KERN_WARNING "%s: SD card claims to support the "
"incompletely defined 'low voltage range'. This "
"will be ignored.\n", mmc_hostname(host));
ocr &= ~MMC_VDD_165_195;
}
host->ocr = mmc_select_voltage(host, ocr);
/*
* Can we support the voltage(s) of the card(s)?
*/
if (!host->ocr) {
err = -EINVAL;
goto err;
}
/*
* Detect and init the card.
*/
err = mmc_sd_init_card(host, host->ocr, NULL);
if (err)
goto err;
mmc_release_host(host);
err = mmc_add_card(host->card);
if (err)
goto remove_card;
return 0;
remove_card:
mmc_remove_card(host->card);
host->card = NULL;
mmc_claim_host(host);
err:
mmc_detach_bus(host);
mmc_release_host(host);
printk(KERN_ERR "%s: error %d whilst initialising SD card\n",
mmc_hostname(host), err);
return err;
}
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