linux/drivers/mmc/core/mmc.c
Ohad Ben-Cohen 12ae637f08 mmc: propagate power save/restore ops return value
Allow power save/restore and their relevant mmc_bus_ops handlers
exit with a return value.

Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Tested-by: Luciano Coelho <luciano.coelho@nokia.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
2010-10-23 21:11:17 +08:00

803 lines
18 KiB
C

/*
* linux/drivers/mmc/core/mmc.c
*
* Copyright (C) 2003-2004 Russell King, All Rights Reserved.
* Copyright (C) 2005-2007 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/err.h>
#include <linux/slab.h>
#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
#include <linux/mmc/mmc.h>
#include "core.h"
#include "bus.h"
#include "mmc_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.
*/
static int mmc_decode_cid(struct mmc_card *card)
{
u32 *resp = card->raw_cid;
/*
* 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(KERN_ERR "%s: card has unknown MMCA version %d\n",
mmc_hostname(card->host), card->csd.mmca_vsn);
return -EINVAL;
}
return 0;
}
static void mmc_set_erase_size(struct mmc_card *card)
{
if (card->ext_csd.erase_group_def & 1)
card->erase_size = card->ext_csd.hc_erase_size;
else
card->erase_size = card->csd.erase_size;
mmc_init_erase(card);
}
/*
* 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, a, b;
u32 *resp = card->raw_csd;
/*
* We only understand CSD structure v1.1 and v1.2.
* v1.2 has extra information in bits 15, 11 and 10.
* We also support eMMC v4.4 & v4.41.
*/
csd->structure = UNSTUFF_BITS(resp, 126, 2);
if (csd->structure == 0) {
printk(KERN_ERR "%s: unrecognised CSD structure version %d\n",
mmc_hostname(card->host), csd->structure);
return -EINVAL;
}
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);
if (csd->write_blkbits >= 9) {
a = UNSTUFF_BITS(resp, 42, 5);
b = UNSTUFF_BITS(resp, 37, 5);
csd->erase_size = (a + 1) * (b + 1);
csd->erase_size <<= csd->write_blkbits - 9;
}
return 0;
}
/*
* Read and decode extended CSD.
*/
static int mmc_read_ext_csd(struct mmc_card *card)
{
int err;
u8 *ext_csd;
BUG_ON(!card);
if (card->csd.mmca_vsn < CSD_SPEC_VER_4)
return 0;
/*
* As the ext_csd is so large and mostly unused, we don't store the
* raw block in mmc_card.
*/
ext_csd = kmalloc(512, GFP_KERNEL);
if (!ext_csd) {
printk(KERN_ERR "%s: could not allocate a buffer to "
"receive the ext_csd.\n", mmc_hostname(card->host));
return -ENOMEM;
}
err = mmc_send_ext_csd(card, ext_csd);
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;
/*
* High capacity cards should have this "magic" size
* stored in their CSD.
*/
if (card->csd.capacity == (4096 * 512)) {
printk(KERN_ERR "%s: unable to read EXT_CSD "
"on a possible high capacity card. "
"Card will be ignored.\n",
mmc_hostname(card->host));
} else {
printk(KERN_WARNING "%s: unable to read "
"EXT_CSD, performance might "
"suffer.\n",
mmc_hostname(card->host));
err = 0;
}
goto out;
}
/* Version is coded in the CSD_STRUCTURE byte in the EXT_CSD register */
if (card->csd.structure == 3) {
int ext_csd_struct = ext_csd[EXT_CSD_STRUCTURE];
if (ext_csd_struct > 2) {
printk(KERN_ERR "%s: unrecognised EXT_CSD structure "
"version %d\n", mmc_hostname(card->host),
ext_csd_struct);
err = -EINVAL;
goto out;
}
}
card->ext_csd.rev = ext_csd[EXT_CSD_REV];
if (card->ext_csd.rev > 5) {
printk(KERN_ERR "%s: unrecognised EXT_CSD revision %d\n",
mmc_hostname(card->host), card->ext_csd.rev);
err = -EINVAL;
goto out;
}
if (card->ext_csd.rev >= 2) {
card->ext_csd.sectors =
ext_csd[EXT_CSD_SEC_CNT + 0] << 0 |
ext_csd[EXT_CSD_SEC_CNT + 1] << 8 |
ext_csd[EXT_CSD_SEC_CNT + 2] << 16 |
ext_csd[EXT_CSD_SEC_CNT + 3] << 24;
/* Cards with density > 2GiB are sector addressed */
if (card->ext_csd.sectors > (2u * 1024 * 1024 * 1024) / 512)
mmc_card_set_blockaddr(card);
}
switch (ext_csd[EXT_CSD_CARD_TYPE] & EXT_CSD_CARD_TYPE_MASK) {
case EXT_CSD_CARD_TYPE_DDR_52 | EXT_CSD_CARD_TYPE_52 |
EXT_CSD_CARD_TYPE_26:
card->ext_csd.hs_max_dtr = 52000000;
card->ext_csd.card_type = EXT_CSD_CARD_TYPE_DDR_52;
break;
case EXT_CSD_CARD_TYPE_DDR_1_2V | EXT_CSD_CARD_TYPE_52 |
EXT_CSD_CARD_TYPE_26:
card->ext_csd.hs_max_dtr = 52000000;
card->ext_csd.card_type = EXT_CSD_CARD_TYPE_DDR_1_2V;
break;
case EXT_CSD_CARD_TYPE_DDR_1_8V | EXT_CSD_CARD_TYPE_52 |
EXT_CSD_CARD_TYPE_26:
card->ext_csd.hs_max_dtr = 52000000;
card->ext_csd.card_type = EXT_CSD_CARD_TYPE_DDR_1_8V;
break;
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(KERN_WARNING "%s: card is mmc v4 but doesn't "
"support any high-speed modes.\n",
mmc_hostname(card->host));
}
if (card->ext_csd.rev >= 3) {
u8 sa_shift = ext_csd[EXT_CSD_S_A_TIMEOUT];
/* Sleep / awake timeout in 100ns units */
if (sa_shift > 0 && sa_shift <= 0x17)
card->ext_csd.sa_timeout =
1 << ext_csd[EXT_CSD_S_A_TIMEOUT];
card->ext_csd.erase_group_def =
ext_csd[EXT_CSD_ERASE_GROUP_DEF];
card->ext_csd.hc_erase_timeout = 300 *
ext_csd[EXT_CSD_ERASE_TIMEOUT_MULT];
card->ext_csd.hc_erase_size =
ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE] << 10;
}
if (card->ext_csd.rev >= 4) {
card->ext_csd.sec_trim_mult =
ext_csd[EXT_CSD_SEC_TRIM_MULT];
card->ext_csd.sec_erase_mult =
ext_csd[EXT_CSD_SEC_ERASE_MULT];
card->ext_csd.sec_feature_support =
ext_csd[EXT_CSD_SEC_FEATURE_SUPPORT];
card->ext_csd.trim_timeout = 300 *
ext_csd[EXT_CSD_TRIM_MULT];
}
if (ext_csd[EXT_CSD_ERASED_MEM_CONT])
card->erased_byte = 0xFF;
else
card->erased_byte = 0x0;
out:
kfree(ext_csd);
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(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 *mmc_std_attrs[] = {
&dev_attr_cid.attr,
&dev_attr_csd.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 mmc_std_attr_group = {
.attrs = mmc_std_attrs,
};
static const struct attribute_group *mmc_attr_groups[] = {
&mmc_std_attr_group,
NULL,
};
static struct device_type mmc_type = {
.groups = mmc_attr_groups,
};
/*
* 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_init_card(struct mmc_host *host, u32 ocr,
struct mmc_card *oldcard)
{
struct mmc_card *card;
int err, ddr = MMC_SDR_MODE;
u32 cid[4];
unsigned int max_dtr;
BUG_ON(!host);
WARN_ON(!host->claimed);
/*
* 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);
/* The extra bit indicates that we support high capacity */
err = mmc_send_op_cond(host, ocr | (1 << 30), NULL);
if (err)
goto err;
/*
* For SPI, enable CRC as appropriate.
*/
if (mmc_host_is_spi(host)) {
err = mmc_spi_set_crc(host, use_spi_crc);
if (err)
goto err;
}
/*
* Fetch CID from card.
*/
if (mmc_host_is_spi(host))
err = mmc_send_cid(host, cid);
else
err = mmc_all_send_cid(host, cid);
if (err)
goto err;
if (oldcard) {
if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0) {
err = -ENOENT;
goto err;
}
card = oldcard;
} else {
/*
* Allocate card structure.
*/
card = mmc_alloc_card(host, &mmc_type);
if (IS_ERR(card)) {
err = PTR_ERR(card);
goto err;
}
card->type = MMC_TYPE_MMC;
card->rca = 1;
memcpy(card->raw_cid, cid, sizeof(card->raw_cid));
}
/*
* For native busses: set card RCA and quit open drain mode.
*/
if (!mmc_host_is_spi(host)) {
err = mmc_set_relative_addr(card);
if (err)
goto free_card;
mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
}
if (!oldcard) {
/*
* Fetch CSD from card.
*/
err = mmc_send_csd(card, card->raw_csd);
if (err)
goto free_card;
err = mmc_decode_csd(card);
if (err)
goto free_card;
err = mmc_decode_cid(card);
if (err)
goto free_card;
}
/*
* Select card, as all following commands rely on that.
*/
if (!mmc_host_is_spi(host)) {
err = mmc_select_card(card);
if (err)
goto free_card;
}
if (!oldcard) {
/*
* Fetch and process extended CSD.
*/
err = mmc_read_ext_csd(card);
if (err)
goto free_card;
/* Erase size depends on CSD and Extended CSD */
mmc_set_erase_size(card);
}
/*
* Activate high speed (if supported)
*/
if ((card->ext_csd.hs_max_dtr != 0) &&
(host->caps & MMC_CAP_MMC_HIGHSPEED)) {
err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
EXT_CSD_HS_TIMING, 1);
if (err && err != -EBADMSG)
goto free_card;
if (err) {
printk(KERN_WARNING "%s: switch to highspeed failed\n",
mmc_hostname(card->host));
err = 0;
} else {
mmc_card_set_highspeed(card);
mmc_set_timing(card->host, MMC_TIMING_MMC_HS);
}
}
/*
* Compute bus speed.
*/
max_dtr = (unsigned int)-1;
if (mmc_card_highspeed(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;
}
mmc_set_clock(host, max_dtr);
/*
* Indicate DDR mode (if supported).
*/
if (mmc_card_highspeed(card)) {
if ((card->ext_csd.card_type & EXT_CSD_CARD_TYPE_DDR_1_8V)
&& (host->caps & (MMC_CAP_1_8V_DDR)))
ddr = MMC_1_8V_DDR_MODE;
else if ((card->ext_csd.card_type & EXT_CSD_CARD_TYPE_DDR_1_2V)
&& (host->caps & (MMC_CAP_1_2V_DDR)))
ddr = MMC_1_2V_DDR_MODE;
}
/*
* Activate wide bus and DDR (if supported).
*/
if ((card->csd.mmca_vsn >= CSD_SPEC_VER_4) &&
(host->caps & (MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA))) {
unsigned ext_csd_bit, bus_width;
if (host->caps & MMC_CAP_8_BIT_DATA) {
if (ddr)
ext_csd_bit = EXT_CSD_DDR_BUS_WIDTH_8;
else
ext_csd_bit = EXT_CSD_BUS_WIDTH_8;
bus_width = MMC_BUS_WIDTH_8;
} else {
if (ddr)
ext_csd_bit = EXT_CSD_DDR_BUS_WIDTH_4;
else
ext_csd_bit = EXT_CSD_BUS_WIDTH_4;
bus_width = MMC_BUS_WIDTH_4;
}
err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
EXT_CSD_BUS_WIDTH, ext_csd_bit);
if (err && err != -EBADMSG)
goto free_card;
if (err) {
printk(KERN_WARNING "%s: switch to bus width %d ddr %d "
"failed\n", mmc_hostname(card->host),
1 << bus_width, ddr);
err = 0;
} else {
mmc_card_set_ddr_mode(card);
mmc_set_bus_width_ddr(card->host, bus_width, ddr);
}
}
if (!oldcard)
host->card = card;
return 0;
free_card:
if (!oldcard)
mmc_remove_card(card);
err:
return err;
}
/*
* Host is being removed. Free up the current card.
*/
static void mmc_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_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_remove(host);
mmc_claim_host(host);
mmc_detach_bus(host);
mmc_release_host(host);
}
}
/*
* Suspend callback from host.
*/
static int mmc_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_resume(struct mmc_host *host)
{
int err;
BUG_ON(!host);
BUG_ON(!host->card);
mmc_claim_host(host);
err = mmc_init_card(host, host->ocr, host->card);
mmc_release_host(host);
return err;
}
static int mmc_power_restore(struct mmc_host *host)
{
int ret;
host->card->state &= ~MMC_STATE_HIGHSPEED;
mmc_claim_host(host);
ret = mmc_init_card(host, host->ocr, host->card);
mmc_release_host(host);
return ret;
}
static int mmc_sleep(struct mmc_host *host)
{
struct mmc_card *card = host->card;
int err = -ENOSYS;
if (card && card->ext_csd.rev >= 3) {
err = mmc_card_sleepawake(host, 1);
if (err < 0)
pr_debug("%s: Error %d while putting card into sleep",
mmc_hostname(host), err);
}
return err;
}
static int mmc_awake(struct mmc_host *host)
{
struct mmc_card *card = host->card;
int err = -ENOSYS;
if (card && card->ext_csd.rev >= 3) {
err = mmc_card_sleepawake(host, 0);
if (err < 0)
pr_debug("%s: Error %d while awaking sleeping card",
mmc_hostname(host), err);
}
return err;
}
static const struct mmc_bus_ops mmc_ops = {
.awake = mmc_awake,
.sleep = mmc_sleep,
.remove = mmc_remove,
.detect = mmc_detect,
.suspend = NULL,
.resume = NULL,
.power_restore = mmc_power_restore,
};
static const struct mmc_bus_ops mmc_ops_unsafe = {
.awake = mmc_awake,
.sleep = mmc_sleep,
.remove = mmc_remove,
.detect = mmc_detect,
.suspend = mmc_suspend,
.resume = mmc_resume,
.power_restore = mmc_power_restore,
};
static void mmc_attach_bus_ops(struct mmc_host *host)
{
const struct mmc_bus_ops *bus_ops;
if (!mmc_card_is_removable(host))
bus_ops = &mmc_ops_unsafe;
else
bus_ops = &mmc_ops;
mmc_attach_bus(host, bus_ops);
}
/*
* Starting point for MMC card init.
*/
int mmc_attach_mmc(struct mmc_host *host, u32 ocr)
{
int err;
BUG_ON(!host);
WARN_ON(!host->claimed);
mmc_attach_bus_ops(host);
/*
* We need to get OCR a different way for SPI.
*/
if (mmc_host_is_spi(host)) {
err = mmc_spi_read_ocr(host, 1, &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;
}
host->ocr = mmc_select_voltage(host, ocr);
/*
* Can we support the voltage of the card?
*/
if (!host->ocr) {
err = -EINVAL;
goto err;
}
/*
* Detect and init the card.
*/
err = mmc_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 MMC card\n",
mmc_hostname(host), err);
return err;
}