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rt-thread/bsp/lm3s9b9x/drivers/sdcard.c

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Re-normalizing the repo
2013-01-08 22:40:58 +08:00
/*-----------------------------------------------------------------------*/
/* MMC/SDC (in SPI mode) control module (C)ChaN, 2007 */
/*-----------------------------------------------------------------------*/
/* Only rcvr_spi(), xmit_spi(), disk_timerproc() and some macros */
/* are platform dependent. */
/*-----------------------------------------------------------------------*/
/*
* This file was modified from a sample available from the FatFs
* web site. It was modified to work with a Luminary Micro
* EK-LM3S6965 evaluation board.
*
* Note that the SSI port is shared with the osram display. The code
* in this file does not attempt to share the SSI port with the osram,
* it assumes the osram is not being used.
*/
#include <rtthread.h>
#include <inc/hw_types.h>
#include <inc/hw_memmap.h>
#include <driverlib/ssi.h>
#include <driverlib/gpio.h>
#include <driverlib/sysctl.h>
/* Status of Disk Functions */
typedef rt_uint8_t DSTATUS;
/* Results of Disk Functions */
typedef enum {
RES_OK = 0, /* 0: Successful */
RES_ERROR, /* 1: R/W Error */
RES_WRPRT, /* 2: Write Protected */
RES_NOTRDY, /* 3: Not Ready */
RES_PARERR /* 4: Invalid Parameter */
} DRESULT;
/* Disk Status Bits (DSTATUS) */
#define STA_NOINIT 0x01 /* Drive not initialized */
#define STA_NODISK 0x02 /* No medium in the drive */
#define STA_PROTECT 0x04 /* Write protected */
/* Definitions for MMC/SDC command */
#define CMD0 (0x40+0) /* GO_IDLE_STATE */
#define CMD1 (0x40+1) /* SEND_OP_COND */
#define CMD8 (0x40+8) /* SEND_IF_COND */
#define CMD9 (0x40+9) /* SEND_CSD */
#define CMD10 (0x40+10) /* SEND_CID */
#define CMD12 (0x40+12) /* STOP_TRANSMISSION */
#define CMD16 (0x40+16) /* SET_BLOCKLEN */
#define CMD17 (0x40+17) /* READ_SINGLE_BLOCK */
#define CMD18 (0x40+18) /* READ_MULTIPLE_BLOCK */
#define CMD23 (0x40+23) /* SET_BLOCK_COUNT */
#define CMD24 (0x40+24) /* WRITE_BLOCK */
#define CMD25 (0x40+25) /* WRITE_MULTIPLE_BLOCK */
#define CMD41 (0x40+41) /* SEND_OP_COND (ACMD) */
#define CMD55 (0x40+55) /* APP_CMD */
#define CMD58 (0x40+58) /* READ_OCR */
/* Command code for disk_ioctrl() */
/* Generic command */
#define CTRL_SYNC 0 /* Mandatory for write functions */
#define GET_SECTOR_COUNT 1 /* Mandatory for only f_mkfs() */
#define GET_SECTOR_SIZE 2 /* Mandatory for multiple sector size cfg */
#define GET_BLOCK_SIZE 3 /* Mandatory for only f_mkfs() */
#define CTRL_POWER 4
#define CTRL_LOCK 5
#define CTRL_EJECT 6
/* MMC/SDC command */
#define MMC_GET_TYPE 10
#define MMC_GET_CSD 11
#define MMC_GET_CID 12
#define MMC_GET_OCR 13
#define MMC_GET_SDSTAT 14
/* ATA/CF command */
#define ATA_GET_REV 20
#define ATA_GET_MODEL 21
#define ATA_GET_SN 22
/* Peripheral definitions for EK-LM3S6965 board */
// SSI port
#define SDC_SSI_BASE SSI0_BASE
#define SDC_SSI_SYSCTL_PERIPH SYSCTL_PERIPH_SSI0
// GPIO for SSI pins
#define SDC_GPIO_PORT_BASE GPIO_PORTA_BASE
#define SDC_GPIO_SYSCTL_PERIPH SYSCTL_PERIPH_GPIOA
#define SDC_SSI_CLK GPIO_PIN_2
#define SDC_SSI_TX GPIO_PIN_5
#define SDC_SSI_RX GPIO_PIN_4
#define SDC_SSI_FSS GPIO_PIN_3
#define SDC_SSI_PINS (SDC_SSI_TX | SDC_SSI_RX | SDC_SSI_CLK)
// GPIO for card chip select
#define SDC_CS_GPIO_PORT_BASE GPIO_PORTG_BASE
#define SDC_CS_GPIO_SYSCTL_PERIPH SYSCTL_PERIPH_GPIOG
#define SDC_CS GPIO_PIN_0
// asserts the CS pin to the card
static
void SELECT (void)
{
GPIOPinWrite(SDC_CS_GPIO_PORT_BASE, SDC_CS, 0);
}
// de-asserts the CS pin to the card
static
void DESELECT (void)
{
GPIOPinWrite(SDC_CS_GPIO_PORT_BASE, SDC_CS, SDC_CS);
}
/*--------------------------------------------------------------------------
Module Private Functions
---------------------------------------------------------------------------*/
static volatile
DSTATUS Stat = STA_NOINIT; /* Disk status */
static volatile
rt_uint8_t Timer1, Timer2; /* 100Hz decrement timer */
static
rt_uint8_t CardType; /* b0:MMC, b1:SDC, b2:Block addressing */
static
rt_uint8_t PowerFlag = 0; /* indicates if "power" is on */
/*-----------------------------------------------------------------------*/
/* Transmit a byte to MMC via SPI (Platform dependent) */
/*-----------------------------------------------------------------------*/
static
void xmit_spi (rt_uint8_t dat)
{
rt_uint32_t rcvdat;
SSIDataPut(SDC_SSI_BASE, dat); /* Write the data to the tx fifo */
SSIDataGet(SDC_SSI_BASE, &rcvdat); /* flush data read during the write */
}
/*-----------------------------------------------------------------------*/
/* Receive a byte from MMC via SPI (Platform dependent) */
/*-----------------------------------------------------------------------*/
static
rt_uint8_t rcvr_spi (void)
{
rt_uint32_t rcvdat;
SSIDataPut(SDC_SSI_BASE, 0xFF); /* write dummy data */
SSIDataGet(SDC_SSI_BASE, &rcvdat); /* read data frm rx fifo */
return (rt_uint8_t)rcvdat;
}
static
void rcvr_spi_m (rt_uint8_t *dst)
{
*dst = rcvr_spi();
}
/*-----------------------------------------------------------------------*/
/* Wait for card ready */
/*-----------------------------------------------------------------------*/
static
rt_uint8_t wait_ready (void)
{
rt_uint8_t res;
Timer2 = 50; /* Wait for ready in timeout of 500ms */
rcvr_spi();
do
res = rcvr_spi();
while ((res != 0xFF) && Timer2);
return res;
}
/*-----------------------------------------------------------------------*/
/* Send 80 or so clock transitions with CS and DI held high. This is */
/* required after card power up to get it into SPI mode */
/*-----------------------------------------------------------------------*/
static
void send_initial_clock_train(void)
{
unsigned int i;
rt_uint32_t dat;
/* Ensure CS is held high. */
DESELECT();
/* Switch the SSI TX line to a GPIO and drive it high too. */
GPIOPinTypeGPIOOutput(SDC_GPIO_PORT_BASE, SDC_SSI_TX);
GPIOPinWrite(SDC_GPIO_PORT_BASE, SDC_SSI_TX, SDC_SSI_TX);
/* Send 10 bytes over the SSI. This causes the clock to wiggle the */
/* required number of times. */
for(i = 0 ; i < 10 ; i++)
{
/* Write DUMMY data. SSIDataPut() waits until there is room in the */
/* FIFO. */
SSIDataPut(SDC_SSI_BASE, 0xFF);
/* Flush data read during data write. */
SSIDataGet(SDC_SSI_BASE, &dat);
}
/* Revert to hardware control of the SSI TX line. */
GPIOPinTypeSSI(SDC_GPIO_PORT_BASE, SDC_SSI_TX);
}
/*-----------------------------------------------------------------------*/
/* Power Control (Platform dependent) */
/*-----------------------------------------------------------------------*/
/* When the target system does not support socket power control, there */
/* is nothing to do in these functions and chk_power always returns 1. */
static
void power_on (void)
{
/*
* This doesn't really turn the power on, but initializes the
* SSI port and pins needed to talk to the card.
*/
/* Enable the peripherals used to drive the SDC on SSI, and the CS */
SysCtlPeripheralEnable(SDC_SSI_SYSCTL_PERIPH);
SysCtlPeripheralEnable(SDC_GPIO_SYSCTL_PERIPH);
SysCtlPeripheralEnable(SDC_CS_GPIO_SYSCTL_PERIPH);
/* Configure the appropriate pins to be SSI instead of GPIO */
GPIOPinTypeSSI(SDC_GPIO_PORT_BASE, SDC_SSI_PINS);
GPIOPinTypeGPIOOutput(SDC_CS_GPIO_PORT_BASE, SDC_CS);
GPIOPadConfigSet(SDC_GPIO_PORT_BASE, SDC_SSI_PINS, GPIO_STRENGTH_4MA,
GPIO_PIN_TYPE_STD_WPU);
GPIOPadConfigSet(SDC_CS_GPIO_PORT_BASE, SDC_CS, GPIO_STRENGTH_4MA,
GPIO_PIN_TYPE_STD_WPU);
/* Deassert the SSI0 chip select */
GPIOPinWrite(SDC_CS_GPIO_PORT_BASE, SDC_CS, SDC_CS);
/* Configure the SSI0 port */
SSIConfigSetExpClk(SDC_SSI_BASE, SysCtlClockGet(), SSI_FRF_MOTO_MODE_0,
SSI_MODE_MASTER, 400000, 8);
SSIEnable(SDC_SSI_BASE);
/* Set DI and CS high and apply more than 74 pulses to SCLK for the card */
/* to be able to accept a native command. */
send_initial_clock_train();
PowerFlag = 1;
}
// set the SSI speed to the max setting
static
void set_max_speed(void)
{
unsigned long i;
/* Disable the SSI */
SSIDisable(SDC_SSI_BASE);
/* Set the maximum speed as half the system clock, with a max of 12.5 MHz. */
i = SysCtlClockGet() / 2;
if(i > 12500000)
{
i = 12500000;
}
/* Configure the SSI0 port */
SSIConfigSetExpClk(SDC_SSI_BASE, SysCtlClockGet(), SSI_FRF_MOTO_MODE_0,
SSI_MODE_MASTER, i, 8);
/* Enable the SSI */
SSIEnable(SDC_SSI_BASE);
}
static
void power_off (void)
{
PowerFlag = 0;
}
static
int chk_power(void) /* Socket power state: 0=off, 1=on */
{
return PowerFlag;
}
/*-----------------------------------------------------------------------*/
/* Receive a data packet from MMC */
/*-----------------------------------------------------------------------*/
static
rt_bool_t rcvr_datablock (
rt_uint8_t *buff, /* Data buffer to store received data */
unsigned int btr /* Byte count (must be even number) */
)
{
rt_uint8_t token;
Timer1 = 10;
do { /* Wait for data packet in timeout of 100ms */
token = rcvr_spi();
} while ((token == 0xFF) && Timer1);
if(token != 0xFE) return RT_FALSE; /* If not valid data token, retutn with error */
do { /* Receive the data block into buffer */
rcvr_spi_m(buff++);
rcvr_spi_m(buff++);
} while (btr -= 2);
rcvr_spi(); /* Discard CRC */
rcvr_spi();
return RT_TRUE; /* Return with success */
}
/*-----------------------------------------------------------------------*/
/* Send a data packet to MMC */
/*-----------------------------------------------------------------------*/
#if _READONLY == 0
static
rt_bool_t xmit_datablock (
const rt_uint8_t *buff, /* 512 byte data block to be transmitted */
rt_uint8_t token /* Data/Stop token */
)
{
rt_uint8_t resp, wc;
if (wait_ready() != 0xFF) return RT_FALSE;
xmit_spi(token); /* Xmit data token */
if (token != 0xFD) { /* Is data token */
wc = 0;
do { /* Xmit the 512 byte data block to MMC */
xmit_spi(*buff++);
xmit_spi(*buff++);
} while (--wc);
xmit_spi(0xFF); /* CRC (Dummy) */
xmit_spi(0xFF);
resp = rcvr_spi(); /* Reveive data response */
if ((resp & 0x1F) != 0x05) /* If not accepted, return with error */
return RT_FALSE;
}
return RT_TRUE;
}
#endif /* _READONLY */
/*-----------------------------------------------------------------------*/
/* Send a command packet to MMC */
/*-----------------------------------------------------------------------*/
static
rt_uint8_t send_cmd (
rt_uint8_t cmd, /* Command byte */
rt_uint32_t arg /* Argument */
)
{
rt_uint8_t n, res;
if (wait_ready() != 0xFF) return 0xFF;
/* Send command packet */
xmit_spi(cmd); /* Command */
xmit_spi((rt_uint8_t)(arg >> 24)); /* Argument[31..24] */
xmit_spi((rt_uint8_t)(arg >> 16)); /* Argument[23..16] */
xmit_spi((rt_uint8_t)(arg >> 8)); /* Argument[15..8] */
xmit_spi((rt_uint8_t)arg); /* Argument[7..0] */
n = 0;
if (cmd == CMD0) n = 0x95; /* CRC for CMD0(0) */
if (cmd == CMD8) n = 0x87; /* CRC for CMD8(0x1AA) */
xmit_spi(n);
/* Receive command response */
if (cmd == CMD12) rcvr_spi(); /* Skip a stuff byte when stop reading */
n = 10; /* Wait for a valid response in timeout of 10 attempts */
do
res = rcvr_spi();
while ((res & 0x80) && --n);
return res; /* Return with the response value */
}
/*--------------------------------------------------------------------------
Public Functions
---------------------------------------------------------------------------*/
/*-----------------------------------------------------------------------*/
/* Initialize Disk Drive */
/*-----------------------------------------------------------------------*/
static
DSTATUS sdcard_initialize (
rt_uint8_t drv /* Physical drive nmuber (0) */
)
{
rt_uint8_t n, ty, ocr[4];
if (drv) return STA_NOINIT; /* Supports only single drive */
if (Stat & STA_NODISK) return Stat; /* No card in the socket */
power_on(); /* Force socket power on */
send_initial_clock_train();
SELECT(); /* CS = L */
ty = 0;
if (send_cmd(CMD0, 0) == 1) { /* Enter Idle state */
Timer1 = 100; /* Initialization timeout of 1000 msec */
if (send_cmd(CMD8, 0x1AA) == 1) { /* SDC Ver2+ */
for (n = 0; n < 4; n++) ocr[n] = rcvr_spi();
if (ocr[2] == 0x01 && ocr[3] == 0xAA) { /* The card can work at vdd range of 2.7-3.6V */
do {
if (send_cmd(CMD55, 0) <= 1 && send_cmd(CMD41, 1UL << 30) == 0) break; /* ACMD41 with HCS bit */
} while (Timer1);
if (Timer1 && send_cmd(CMD58, 0) == 0) { /* Check CCS bit */
for (n = 0; n < 4; n++) ocr[n] = rcvr_spi();
ty = (ocr[0] & 0x40) ? 6 : 2;
}
}
} else { /* SDC Ver1 or MMC */
ty = (send_cmd(CMD55, 0) <= 1 && send_cmd(CMD41, 0) <= 1) ? 2 : 1; /* SDC : MMC */
do {
if (ty == 2) {
if (send_cmd(CMD55, 0) <= 1 && send_cmd(CMD41, 0) == 0) break; /* ACMD41 */
} else {
if (send_cmd(CMD1, 0) == 0) break; /* CMD1 */
}
} while (Timer1);
if (!Timer1 || send_cmd(CMD16, 512) != 0) /* Select R/W block length */
ty = 0;
}
}
CardType = ty;
DESELECT(); /* CS = H */
rcvr_spi(); /* Idle (Release DO) */
if (ty) { /* Initialization succeded */
Stat &= ~STA_NOINIT; /* Clear STA_NOINIT */
set_max_speed();
} else { /* Initialization failed */
power_off();
}
return Stat;
}
/*-----------------------------------------------------------------------*/
/* Read Sector(s) */
/*-----------------------------------------------------------------------*/
static
DRESULT sdcard_read (
rt_uint8_t drv, /* Physical drive nmuber (0) */
rt_uint8_t *buff, /* Pointer to the data buffer to store read data */
rt_uint32_t sector, /* Start sector number (LBA) */
rt_uint8_t count /* Sector count (1..255) */
)
{
if (drv || !count) return RES_PARERR;
if (Stat & STA_NOINIT) return RES_NOTRDY;
if (!(CardType & 4)) sector *= 512; /* Convert to byte address if needed */
SELECT(); /* CS = L */
if (count == 1) { /* Single block read */
if ((send_cmd(CMD17, sector) == 0) /* READ_SINGLE_BLOCK */
&& rcvr_datablock(buff, 512))
count = 0;
}
else { /* Multiple block read */
if (send_cmd(CMD18, sector) == 0) { /* READ_MULTIPLE_BLOCK */
do {
if (!rcvr_datablock(buff, 512)) break;
buff += 512;
} while (--count);
send_cmd(CMD12, 0); /* STOP_TRANSMISSION */
}
}
DESELECT(); /* CS = H */
rcvr_spi(); /* Idle (Release DO) */
return count ? RES_ERROR : RES_OK;
}
/*-----------------------------------------------------------------------*/
/* Write Sector(s) */
/*-----------------------------------------------------------------------*/
#if _READONLY == 0
static
DRESULT sdcard_write (
rt_uint8_t drv, /* Physical drive nmuber (0) */
const rt_uint8_t *buff, /* Pointer to the data to be written */
rt_uint32_t sector, /* Start sector number (LBA) */
rt_uint8_t count /* Sector count (1..255) */
)
{
if (drv || !count) return RES_PARERR;
if (Stat & STA_NOINIT) return RES_NOTRDY;
if (Stat & STA_PROTECT) return RES_WRPRT;
if (!(CardType & 4)) sector *= 512; /* Convert to byte address if needed */
SELECT(); /* CS = L */
if (count == 1) { /* Single block write */
if ((send_cmd(CMD24, sector) == 0) /* WRITE_BLOCK */
&& xmit_datablock(buff, 0xFE))
count = 0;
}
else { /* Multiple block write */
if (CardType & 2) {
send_cmd(CMD55, 0); send_cmd(CMD23, count); /* ACMD23 */
}
if (send_cmd(CMD25, sector) == 0) { /* WRITE_MULTIPLE_BLOCK */
do {
if (!xmit_datablock(buff, 0xFC)) break;
buff += 512;
} while (--count);
if (!xmit_datablock(0, 0xFD)) /* STOP_TRAN token */
count = 1;
}
}
DESELECT(); /* CS = H */
rcvr_spi(); /* Idle (Release DO) */
return count ? RES_ERROR : RES_OK;
}
#endif /* _READONLY */
/*-----------------------------------------------------------------------*/
/* Miscellaneous Functions */
/*-----------------------------------------------------------------------*/
static
DRESULT sdcard_ioctl (
rt_uint8_t drv, /* Physical drive nmuber (0) */
rt_uint8_t ctrl, /* Control code */
void *buff /* Buffer to send/receive control data */
)
{
DRESULT res;
rt_uint8_t n, csd[16], *ptr = buff;
rt_uint16_t csize;
if (drv) return RES_PARERR;
res = RES_ERROR;
if (ctrl == CTRL_POWER) {
switch (*ptr) {
case 0: /* Sub control code == 0 (POWER_OFF) */
if (chk_power())
power_off(); /* Power off */
res = RES_OK;
break;
case 1: /* Sub control code == 1 (POWER_ON) */
power_on(); /* Power on */
res = RES_OK;
break;
case 2: /* Sub control code == 2 (POWER_GET) */
*(ptr+1) = (rt_uint8_t)chk_power();
res = RES_OK;
break;
default :
res = RES_PARERR;
}
}
else {
if (Stat & STA_NOINIT) return RES_NOTRDY;
SELECT(); /* CS = L */
switch (ctrl) {
case GET_SECTOR_COUNT : /* Get number of sectors on the disk (rt_uint32_t) */
if ((send_cmd(CMD9, 0) == 0) && rcvr_datablock(csd, 16)) {
if ((csd[0] >> 6) == 1) { /* SDC ver 2.00 */
csize = csd[9] + ((rt_uint16_t)csd[8] << 8) + 1;
*(rt_uint32_t*)buff = (rt_uint32_t)csize << 10;
} else { /* MMC or SDC ver 1.XX */
n = (csd[5] & 15) + ((csd[10] & 128) >> 7) + ((csd[9] & 3) << 1) + 2;
csize = (csd[8] >> 6) + ((rt_uint16_t)csd[7] << 2) + ((rt_uint16_t)(csd[6] & 3) << 10) + 1;
*(rt_uint32_t*)buff = (rt_uint32_t)csize << (n - 9);
}
res = RES_OK;
}
break;
case GET_SECTOR_SIZE : /* Get sectors on the disk (rt_uint16_t) */
*(rt_uint16_t*)buff = 512;
res = RES_OK;
break;
case CTRL_SYNC : /* Make sure that data has been written */
if (wait_ready() == 0xFF)
res = RES_OK;
break;
case MMC_GET_CSD : /* Receive CSD as a data block (16 bytes) */
if (send_cmd(CMD9, 0) == 0 /* READ_CSD */
&& rcvr_datablock(ptr, 16))
res = RES_OK;
break;
case MMC_GET_CID : /* Receive CID as a data block (16 bytes) */
if (send_cmd(CMD10, 0) == 0 /* READ_CID */
&& rcvr_datablock(ptr, 16))
res = RES_OK;
break;
case MMC_GET_OCR : /* Receive OCR as an R3 resp (4 bytes) */
if (send_cmd(CMD58, 0) == 0) { /* READ_OCR */
for (n = 0; n < 4; n++)
*ptr++ = rcvr_spi();
res = RES_OK;
}
// case MMC_GET_TYPE : /* Get card type flags (1 byte) */
// *ptr = CardType;
// res = RES_OK;
// break;
default:
res = RES_PARERR;
}
DESELECT(); /* CS = H */
rcvr_spi(); /* Idle (Release DO) */
}
return res;
}
/*
* RT-Thread SD Card Driver
* 20090705 Yi.Qiu
*/
#include <rtthread.h>
#include <dfs_fs.h>
struct rt_device sdcard_device;
struct dfs_partition part;
/* RT-Thread Device Driver Interface */
static rt_err_t rt_sdcard_init(rt_device_t dev)
{
return RT_EOK;
}
static rt_err_t rt_sdcard_open(rt_device_t dev, rt_uint16_t oflag)
{
return RT_EOK;
}
static rt_err_t rt_sdcard_close(rt_device_t dev)
{
return RT_EOK;
}
static rt_size_t rt_sdcard_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
{
DRESULT status;
status = sdcard_read(0, buffer, part.offset + pos, size);
if (status != RES_OK)
{
rt_kprintf("sd card read failed\n");
return 0;
}
return size;
}
static rt_size_t rt_sdcard_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
{
DRESULT status;
status = sdcard_write(0, buffer, part.offset + pos, size);
if (status != RES_OK)
{
rt_kprintf("sd card write failed\n");
return 0;
}
return size;
}
static rt_err_t rt_sdcard_control(rt_device_t dev, rt_uint8_t cmd, void *args)
{
return RT_EOK;
}
void rt_hw_sdcard_init(void)
{
if (sdcard_initialize(0) == RES_OK)
{
DRESULT status;
rt_uint8_t *sector;
/* get the first sector to read partition table */
sector = (rt_uint8_t*) rt_malloc (512);
if (sector == RT_NULL)
{
rt_kprintf("allocate partition sector buffer failed\n");
return;
}
status = sdcard_read(0, sector, 0, 1);
if (status == RES_OK)
{
/* get the first partition */
if (dfs_filesystem_get_partition(&part, sector, 0) != 0)
{
/* there is no partition */
part.offset = 0;
part.size = 0;
}
}
else
{
/* there is no partition table */
part.offset = 0;
part.size = 0;
}
/* release sector buffer */
rt_free(sector);
/* register sdcard device */
sdcard_device.type = RT_Device_Class_Block;
sdcard_device.init = rt_sdcard_init;
sdcard_device.open = rt_sdcard_open;
sdcard_device.close = rt_sdcard_close;
sdcard_device.read = rt_sdcard_read;
sdcard_device.write = rt_sdcard_write;
sdcard_device.control = rt_sdcard_control;
/* no private */
sdcard_device.user_data = RT_NULL;
rt_device_register(&sdcard_device, "sd0",
RT_DEVICE_FLAG_RDWR | RT_DEVICE_FLAG_REMOVABLE | RT_DEVICE_FLAG_STANDALONE);
return;
}
rt_kprintf("sdcard init failed\n");
}