linux/drivers/mmc/core/mmc_ops.c
Chaotian Jing 3bbb0deea6 mmc: core: fix __mmc_switch timeout caused by preempt
there is a time window between __mmc_send_status() and time_afer(),
on some eMMC chip, the timeout_ms is only 10ms, if this thread was
scheduled out during this period, then, even card has already changes
to transfer state by the result of CMD13, this part of code also treat
it to timeout error.
So, need calculate timeout first, then call __mmc_send_status(), if
already timeout and card still in programing state, then treat it to
the real timeout error.

Signed-off-by: Chaotian Jing <chaotian.jing@mediatek.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-12-22 11:32:18 +01:00

804 lines
18 KiB
C

/*
* linux/drivers/mmc/core/mmc_ops.h
*
* Copyright 2006-2007 Pierre Ossman
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*/
#include <linux/slab.h>
#include <linux/export.h>
#include <linux/types.h>
#include <linux/scatterlist.h>
#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
#include <linux/mmc/mmc.h>
#include "core.h"
#include "host.h"
#include "mmc_ops.h"
#define MMC_OPS_TIMEOUT_MS (10 * 60 * 1000) /* 10 minute timeout */
static const u8 tuning_blk_pattern_4bit[] = {
0xff, 0x0f, 0xff, 0x00, 0xff, 0xcc, 0xc3, 0xcc,
0xc3, 0x3c, 0xcc, 0xff, 0xfe, 0xff, 0xfe, 0xef,
0xff, 0xdf, 0xff, 0xdd, 0xff, 0xfb, 0xff, 0xfb,
0xbf, 0xff, 0x7f, 0xff, 0x77, 0xf7, 0xbd, 0xef,
0xff, 0xf0, 0xff, 0xf0, 0x0f, 0xfc, 0xcc, 0x3c,
0xcc, 0x33, 0xcc, 0xcf, 0xff, 0xef, 0xff, 0xee,
0xff, 0xfd, 0xff, 0xfd, 0xdf, 0xff, 0xbf, 0xff,
0xbb, 0xff, 0xf7, 0xff, 0xf7, 0x7f, 0x7b, 0xde,
};
static const u8 tuning_blk_pattern_8bit[] = {
0xff, 0xff, 0x00, 0xff, 0xff, 0xff, 0x00, 0x00,
0xff, 0xff, 0xcc, 0xcc, 0xcc, 0x33, 0xcc, 0xcc,
0xcc, 0x33, 0x33, 0xcc, 0xcc, 0xcc, 0xff, 0xff,
0xff, 0xee, 0xff, 0xff, 0xff, 0xee, 0xee, 0xff,
0xff, 0xff, 0xdd, 0xff, 0xff, 0xff, 0xdd, 0xdd,
0xff, 0xff, 0xff, 0xbb, 0xff, 0xff, 0xff, 0xbb,
0xbb, 0xff, 0xff, 0xff, 0x77, 0xff, 0xff, 0xff,
0x77, 0x77, 0xff, 0x77, 0xbb, 0xdd, 0xee, 0xff,
0xff, 0xff, 0xff, 0x00, 0xff, 0xff, 0xff, 0x00,
0x00, 0xff, 0xff, 0xcc, 0xcc, 0xcc, 0x33, 0xcc,
0xcc, 0xcc, 0x33, 0x33, 0xcc, 0xcc, 0xcc, 0xff,
0xff, 0xff, 0xee, 0xff, 0xff, 0xff, 0xee, 0xee,
0xff, 0xff, 0xff, 0xdd, 0xff, 0xff, 0xff, 0xdd,
0xdd, 0xff, 0xff, 0xff, 0xbb, 0xff, 0xff, 0xff,
0xbb, 0xbb, 0xff, 0xff, 0xff, 0x77, 0xff, 0xff,
0xff, 0x77, 0x77, 0xff, 0x77, 0xbb, 0xdd, 0xee,
};
static inline int __mmc_send_status(struct mmc_card *card, u32 *status,
bool ignore_crc)
{
int err;
struct mmc_command cmd = {0};
BUG_ON(!card);
BUG_ON(!card->host);
cmd.opcode = MMC_SEND_STATUS;
if (!mmc_host_is_spi(card->host))
cmd.arg = card->rca << 16;
cmd.flags = MMC_RSP_SPI_R2 | MMC_RSP_R1 | MMC_CMD_AC;
if (ignore_crc)
cmd.flags &= ~MMC_RSP_CRC;
err = mmc_wait_for_cmd(card->host, &cmd, MMC_CMD_RETRIES);
if (err)
return err;
/* NOTE: callers are required to understand the difference
* between "native" and SPI format status words!
*/
if (status)
*status = cmd.resp[0];
return 0;
}
int mmc_send_status(struct mmc_card *card, u32 *status)
{
return __mmc_send_status(card, status, false);
}
static int _mmc_select_card(struct mmc_host *host, struct mmc_card *card)
{
int err;
struct mmc_command cmd = {0};
BUG_ON(!host);
cmd.opcode = MMC_SELECT_CARD;
if (card) {
cmd.arg = card->rca << 16;
cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
} else {
cmd.arg = 0;
cmd.flags = MMC_RSP_NONE | MMC_CMD_AC;
}
err = mmc_wait_for_cmd(host, &cmd, MMC_CMD_RETRIES);
if (err)
return err;
return 0;
}
int mmc_select_card(struct mmc_card *card)
{
BUG_ON(!card);
return _mmc_select_card(card->host, card);
}
int mmc_deselect_cards(struct mmc_host *host)
{
return _mmc_select_card(host, NULL);
}
/*
* Write the value specified in the device tree or board code into the optional
* 16 bit Driver Stage Register. This can be used to tune raise/fall times and
* drive strength of the DAT and CMD outputs. The actual meaning of a given
* value is hardware dependant.
* The presence of the DSR register can be determined from the CSD register,
* bit 76.
*/
int mmc_set_dsr(struct mmc_host *host)
{
struct mmc_command cmd = {0};
cmd.opcode = MMC_SET_DSR;
cmd.arg = (host->dsr << 16) | 0xffff;
cmd.flags = MMC_RSP_NONE | MMC_CMD_AC;
return mmc_wait_for_cmd(host, &cmd, MMC_CMD_RETRIES);
}
int mmc_go_idle(struct mmc_host *host)
{
int err;
struct mmc_command cmd = {0};
/*
* Non-SPI hosts need to prevent chipselect going active during
* GO_IDLE; that would put chips into SPI mode. Remind them of
* that in case of hardware that won't pull up DAT3/nCS otherwise.
*
* SPI hosts ignore ios.chip_select; it's managed according to
* rules that must accommodate non-MMC slaves which this layer
* won't even know about.
*/
if (!mmc_host_is_spi(host)) {
mmc_set_chip_select(host, MMC_CS_HIGH);
mmc_delay(1);
}
cmd.opcode = MMC_GO_IDLE_STATE;
cmd.arg = 0;
cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_NONE | MMC_CMD_BC;
err = mmc_wait_for_cmd(host, &cmd, 0);
mmc_delay(1);
if (!mmc_host_is_spi(host)) {
mmc_set_chip_select(host, MMC_CS_DONTCARE);
mmc_delay(1);
}
host->use_spi_crc = 0;
return err;
}
int mmc_send_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr)
{
struct mmc_command cmd = {0};
int i, err = 0;
BUG_ON(!host);
cmd.opcode = MMC_SEND_OP_COND;
cmd.arg = mmc_host_is_spi(host) ? 0 : ocr;
cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R3 | MMC_CMD_BCR;
for (i = 100; i; i--) {
err = mmc_wait_for_cmd(host, &cmd, 0);
if (err)
break;
/* if we're just probing, do a single pass */
if (ocr == 0)
break;
/* otherwise wait until reset completes */
if (mmc_host_is_spi(host)) {
if (!(cmd.resp[0] & R1_SPI_IDLE))
break;
} else {
if (cmd.resp[0] & MMC_CARD_BUSY)
break;
}
err = -ETIMEDOUT;
mmc_delay(10);
}
if (rocr && !mmc_host_is_spi(host))
*rocr = cmd.resp[0];
return err;
}
int mmc_all_send_cid(struct mmc_host *host, u32 *cid)
{
int err;
struct mmc_command cmd = {0};
BUG_ON(!host);
BUG_ON(!cid);
cmd.opcode = MMC_ALL_SEND_CID;
cmd.arg = 0;
cmd.flags = MMC_RSP_R2 | MMC_CMD_BCR;
err = mmc_wait_for_cmd(host, &cmd, MMC_CMD_RETRIES);
if (err)
return err;
memcpy(cid, cmd.resp, sizeof(u32) * 4);
return 0;
}
int mmc_set_relative_addr(struct mmc_card *card)
{
int err;
struct mmc_command cmd = {0};
BUG_ON(!card);
BUG_ON(!card->host);
cmd.opcode = MMC_SET_RELATIVE_ADDR;
cmd.arg = card->rca << 16;
cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
err = mmc_wait_for_cmd(card->host, &cmd, MMC_CMD_RETRIES);
if (err)
return err;
return 0;
}
static int
mmc_send_cxd_native(struct mmc_host *host, u32 arg, u32 *cxd, int opcode)
{
int err;
struct mmc_command cmd = {0};
BUG_ON(!host);
BUG_ON(!cxd);
cmd.opcode = opcode;
cmd.arg = arg;
cmd.flags = MMC_RSP_R2 | MMC_CMD_AC;
err = mmc_wait_for_cmd(host, &cmd, MMC_CMD_RETRIES);
if (err)
return err;
memcpy(cxd, cmd.resp, sizeof(u32) * 4);
return 0;
}
/*
* NOTE: void *buf, caller for the buf is required to use DMA-capable
* buffer or on-stack buffer (with some overhead in callee).
*/
static int
mmc_send_cxd_data(struct mmc_card *card, struct mmc_host *host,
u32 opcode, void *buf, unsigned len)
{
struct mmc_request mrq = {NULL};
struct mmc_command cmd = {0};
struct mmc_data data = {0};
struct scatterlist sg;
mrq.cmd = &cmd;
mrq.data = &data;
cmd.opcode = opcode;
cmd.arg = 0;
/* NOTE HACK: the MMC_RSP_SPI_R1 is always correct here, but we
* rely on callers to never use this with "native" calls for reading
* CSD or CID. Native versions of those commands use the R2 type,
* not R1 plus a data block.
*/
cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
data.blksz = len;
data.blocks = 1;
data.flags = MMC_DATA_READ;
data.sg = &sg;
data.sg_len = 1;
sg_init_one(&sg, buf, len);
if (opcode == MMC_SEND_CSD || opcode == MMC_SEND_CID) {
/*
* The spec states that CSR and CID accesses have a timeout
* of 64 clock cycles.
*/
data.timeout_ns = 0;
data.timeout_clks = 64;
} else
mmc_set_data_timeout(&data, card);
mmc_wait_for_req(host, &mrq);
if (cmd.error)
return cmd.error;
if (data.error)
return data.error;
return 0;
}
int mmc_send_csd(struct mmc_card *card, u32 *csd)
{
int ret, i;
u32 *csd_tmp;
if (!mmc_host_is_spi(card->host))
return mmc_send_cxd_native(card->host, card->rca << 16,
csd, MMC_SEND_CSD);
csd_tmp = kzalloc(16, GFP_KERNEL);
if (!csd_tmp)
return -ENOMEM;
ret = mmc_send_cxd_data(card, card->host, MMC_SEND_CSD, csd_tmp, 16);
if (ret)
goto err;
for (i = 0;i < 4;i++)
csd[i] = be32_to_cpu(csd_tmp[i]);
err:
kfree(csd_tmp);
return ret;
}
int mmc_send_cid(struct mmc_host *host, u32 *cid)
{
int ret, i;
u32 *cid_tmp;
if (!mmc_host_is_spi(host)) {
if (!host->card)
return -EINVAL;
return mmc_send_cxd_native(host, host->card->rca << 16,
cid, MMC_SEND_CID);
}
cid_tmp = kzalloc(16, GFP_KERNEL);
if (!cid_tmp)
return -ENOMEM;
ret = mmc_send_cxd_data(NULL, host, MMC_SEND_CID, cid_tmp, 16);
if (ret)
goto err;
for (i = 0;i < 4;i++)
cid[i] = be32_to_cpu(cid_tmp[i]);
err:
kfree(cid_tmp);
return ret;
}
int mmc_get_ext_csd(struct mmc_card *card, u8 **new_ext_csd)
{
int err;
u8 *ext_csd;
if (!card || !new_ext_csd)
return -EINVAL;
if (!mmc_can_ext_csd(card))
return -EOPNOTSUPP;
/*
* As the ext_csd is so large and mostly unused, we don't store the
* raw block in mmc_card.
*/
ext_csd = kzalloc(512, GFP_KERNEL);
if (!ext_csd)
return -ENOMEM;
err = mmc_send_cxd_data(card, card->host, MMC_SEND_EXT_CSD, ext_csd,
512);
if (err)
kfree(ext_csd);
else
*new_ext_csd = ext_csd;
return err;
}
EXPORT_SYMBOL_GPL(mmc_get_ext_csd);
int mmc_spi_read_ocr(struct mmc_host *host, int highcap, u32 *ocrp)
{
struct mmc_command cmd = {0};
int err;
cmd.opcode = MMC_SPI_READ_OCR;
cmd.arg = highcap ? (1 << 30) : 0;
cmd.flags = MMC_RSP_SPI_R3;
err = mmc_wait_for_cmd(host, &cmd, 0);
*ocrp = cmd.resp[1];
return err;
}
int mmc_spi_set_crc(struct mmc_host *host, int use_crc)
{
struct mmc_command cmd = {0};
int err;
cmd.opcode = MMC_SPI_CRC_ON_OFF;
cmd.flags = MMC_RSP_SPI_R1;
cmd.arg = use_crc;
err = mmc_wait_for_cmd(host, &cmd, 0);
if (!err)
host->use_spi_crc = use_crc;
return err;
}
int mmc_switch_status_error(struct mmc_host *host, u32 status)
{
if (mmc_host_is_spi(host)) {
if (status & R1_SPI_ILLEGAL_COMMAND)
return -EBADMSG;
} else {
if (status & 0xFDFFA000)
pr_warn("%s: unexpected status %#x after switch\n",
mmc_hostname(host), status);
if (status & R1_SWITCH_ERROR)
return -EBADMSG;
}
return 0;
}
/**
* __mmc_switch - modify EXT_CSD register
* @card: the MMC card associated with the data transfer
* @set: cmd set values
* @index: EXT_CSD register index
* @value: value to program into EXT_CSD register
* @timeout_ms: timeout (ms) for operation performed by register write,
* timeout of zero implies maximum possible timeout
* @use_busy_signal: use the busy signal as response type
* @send_status: send status cmd to poll for busy
* @ignore_crc: ignore CRC errors when sending status cmd to poll for busy
*
* Modifies the EXT_CSD register for selected card.
*/
int __mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value,
unsigned int timeout_ms, bool use_busy_signal, bool send_status,
bool ignore_crc)
{
struct mmc_host *host = card->host;
int err;
struct mmc_command cmd = {0};
unsigned long timeout;
u32 status = 0;
bool use_r1b_resp = use_busy_signal;
bool expired = false;
mmc_retune_hold(host);
/*
* If the cmd timeout and the max_busy_timeout of the host are both
* specified, let's validate them. A failure means we need to prevent
* the host from doing hw busy detection, which is done by converting
* to a R1 response instead of a R1B.
*/
if (timeout_ms && host->max_busy_timeout &&
(timeout_ms > host->max_busy_timeout))
use_r1b_resp = false;
cmd.opcode = MMC_SWITCH;
cmd.arg = (MMC_SWITCH_MODE_WRITE_BYTE << 24) |
(index << 16) |
(value << 8) |
set;
cmd.flags = MMC_CMD_AC;
if (use_r1b_resp) {
cmd.flags |= MMC_RSP_SPI_R1B | MMC_RSP_R1B;
/*
* A busy_timeout of zero means the host can decide to use
* whatever value it finds suitable.
*/
cmd.busy_timeout = timeout_ms;
} else {
cmd.flags |= MMC_RSP_SPI_R1 | MMC_RSP_R1;
}
if (index == EXT_CSD_SANITIZE_START)
cmd.sanitize_busy = true;
err = mmc_wait_for_cmd(host, &cmd, MMC_CMD_RETRIES);
if (err)
goto out;
/* No need to check card status in case of unblocking command */
if (!use_busy_signal)
goto out;
/*
* CRC errors shall only be ignored in cases were CMD13 is used to poll
* to detect busy completion.
*/
if ((host->caps & MMC_CAP_WAIT_WHILE_BUSY) && use_r1b_resp)
ignore_crc = false;
/* We have an unspecified cmd timeout, use the fallback value. */
if (!timeout_ms)
timeout_ms = MMC_OPS_TIMEOUT_MS;
/* Must check status to be sure of no errors. */
timeout = jiffies + msecs_to_jiffies(timeout_ms);
do {
if (send_status) {
/*
* Due to the possibility of being preempted after
* sending the status command, check the expiration
* time first.
*/
expired = time_after(jiffies, timeout);
err = __mmc_send_status(card, &status, ignore_crc);
if (err)
goto out;
}
if ((host->caps & MMC_CAP_WAIT_WHILE_BUSY) && use_r1b_resp)
break;
if (mmc_host_is_spi(host))
break;
/*
* We are not allowed to issue a status command and the host
* does'nt support MMC_CAP_WAIT_WHILE_BUSY, then we can only
* rely on waiting for the stated timeout to be sufficient.
*/
if (!send_status) {
mmc_delay(timeout_ms);
goto out;
}
/* Timeout if the device never leaves the program state. */
if (expired && R1_CURRENT_STATE(status) == R1_STATE_PRG) {
pr_err("%s: Card stuck in programming state! %s\n",
mmc_hostname(host), __func__);
err = -ETIMEDOUT;
goto out;
}
} while (R1_CURRENT_STATE(status) == R1_STATE_PRG);
err = mmc_switch_status_error(host, status);
out:
mmc_retune_release(host);
return err;
}
int mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value,
unsigned int timeout_ms)
{
return __mmc_switch(card, set, index, value, timeout_ms, true, true,
false);
}
EXPORT_SYMBOL_GPL(mmc_switch);
int mmc_send_tuning(struct mmc_host *host, u32 opcode, int *cmd_error)
{
struct mmc_request mrq = {NULL};
struct mmc_command cmd = {0};
struct mmc_data data = {0};
struct scatterlist sg;
struct mmc_ios *ios = &host->ios;
const u8 *tuning_block_pattern;
int size, err = 0;
u8 *data_buf;
if (ios->bus_width == MMC_BUS_WIDTH_8) {
tuning_block_pattern = tuning_blk_pattern_8bit;
size = sizeof(tuning_blk_pattern_8bit);
} else if (ios->bus_width == MMC_BUS_WIDTH_4) {
tuning_block_pattern = tuning_blk_pattern_4bit;
size = sizeof(tuning_blk_pattern_4bit);
} else
return -EINVAL;
data_buf = kzalloc(size, GFP_KERNEL);
if (!data_buf)
return -ENOMEM;
mrq.cmd = &cmd;
mrq.data = &data;
cmd.opcode = opcode;
cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
data.blksz = size;
data.blocks = 1;
data.flags = MMC_DATA_READ;
/*
* According to the tuning specs, Tuning process
* is normally shorter 40 executions of CMD19,
* and timeout value should be shorter than 150 ms
*/
data.timeout_ns = 150 * NSEC_PER_MSEC;
data.sg = &sg;
data.sg_len = 1;
sg_init_one(&sg, data_buf, size);
mmc_wait_for_req(host, &mrq);
if (cmd_error)
*cmd_error = cmd.error;
if (cmd.error) {
err = cmd.error;
goto out;
}
if (data.error) {
err = data.error;
goto out;
}
if (memcmp(data_buf, tuning_block_pattern, size))
err = -EIO;
out:
kfree(data_buf);
return err;
}
EXPORT_SYMBOL_GPL(mmc_send_tuning);
static int
mmc_send_bus_test(struct mmc_card *card, struct mmc_host *host, u8 opcode,
u8 len)
{
struct mmc_request mrq = {NULL};
struct mmc_command cmd = {0};
struct mmc_data data = {0};
struct scatterlist sg;
u8 *data_buf;
u8 *test_buf;
int i, err;
static u8 testdata_8bit[8] = { 0x55, 0xaa, 0, 0, 0, 0, 0, 0 };
static u8 testdata_4bit[4] = { 0x5a, 0, 0, 0 };
/* dma onto stack is unsafe/nonportable, but callers to this
* routine normally provide temporary on-stack buffers ...
*/
data_buf = kmalloc(len, GFP_KERNEL);
if (!data_buf)
return -ENOMEM;
if (len == 8)
test_buf = testdata_8bit;
else if (len == 4)
test_buf = testdata_4bit;
else {
pr_err("%s: Invalid bus_width %d\n",
mmc_hostname(host), len);
kfree(data_buf);
return -EINVAL;
}
if (opcode == MMC_BUS_TEST_W)
memcpy(data_buf, test_buf, len);
mrq.cmd = &cmd;
mrq.data = &data;
cmd.opcode = opcode;
cmd.arg = 0;
/* NOTE HACK: the MMC_RSP_SPI_R1 is always correct here, but we
* rely on callers to never use this with "native" calls for reading
* CSD or CID. Native versions of those commands use the R2 type,
* not R1 plus a data block.
*/
cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
data.blksz = len;
data.blocks = 1;
if (opcode == MMC_BUS_TEST_R)
data.flags = MMC_DATA_READ;
else
data.flags = MMC_DATA_WRITE;
data.sg = &sg;
data.sg_len = 1;
mmc_set_data_timeout(&data, card);
sg_init_one(&sg, data_buf, len);
mmc_wait_for_req(host, &mrq);
err = 0;
if (opcode == MMC_BUS_TEST_R) {
for (i = 0; i < len / 4; i++)
if ((test_buf[i] ^ data_buf[i]) != 0xff) {
err = -EIO;
break;
}
}
kfree(data_buf);
if (cmd.error)
return cmd.error;
if (data.error)
return data.error;
return err;
}
int mmc_bus_test(struct mmc_card *card, u8 bus_width)
{
int err, width;
if (bus_width == MMC_BUS_WIDTH_8)
width = 8;
else if (bus_width == MMC_BUS_WIDTH_4)
width = 4;
else if (bus_width == MMC_BUS_WIDTH_1)
return 0; /* no need for test */
else
return -EINVAL;
/*
* Ignore errors from BUS_TEST_W. BUS_TEST_R will fail if there
* is a problem. This improves chances that the test will work.
*/
mmc_send_bus_test(card, card->host, MMC_BUS_TEST_W, width);
err = mmc_send_bus_test(card, card->host, MMC_BUS_TEST_R, width);
return err;
}
int mmc_send_hpi_cmd(struct mmc_card *card, u32 *status)
{
struct mmc_command cmd = {0};
unsigned int opcode;
int err;
if (!card->ext_csd.hpi) {
pr_warn("%s: Card didn't support HPI command\n",
mmc_hostname(card->host));
return -EINVAL;
}
opcode = card->ext_csd.hpi_cmd;
if (opcode == MMC_STOP_TRANSMISSION)
cmd.flags = MMC_RSP_R1B | MMC_CMD_AC;
else if (opcode == MMC_SEND_STATUS)
cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
cmd.opcode = opcode;
cmd.arg = card->rca << 16 | 1;
err = mmc_wait_for_cmd(card->host, &cmd, 0);
if (err) {
pr_warn("%s: error %d interrupting operation. "
"HPI command response %#x\n", mmc_hostname(card->host),
err, cmd.resp[0]);
return err;
}
if (status)
*status = cmd.resp[0];
return 0;
}
int mmc_can_ext_csd(struct mmc_card *card)
{
return (card && card->csd.mmca_vsn > CSD_SPEC_VER_3);
}