mmc_spi_logicpd_lh79520.c

嵌入式文件系统 ucfs.包含全部源代码

/*
**********************************************************************
*                          Micrium, Inc.
*                      949 Crestview Circle
*                     Weston,  FL 33327-1848
*
*                            uC/FS
*
*             (c) Copyright 2001 - 2003, Micrium, Inc.
*                      All rights reserved.
*
***********************************************************************

----------------------------------------------------------------------
File        : mmc_x_hw.c
Purpose     : Sample MMC hardware layer for LogicPD
---------------------------END-OF-HEADER------------------------------
*/

/*********************************************************************
*
*             #include Section
*
**********************************************************************
*/

#include "fs_api.h"
#include "fs_conf.h"

#if FS_USE_MMC_DRIVER

#include "mmc.h"
#include "mmc_x_hw.h"
#include "iolh79520.h"

/*********************************************************************
*
*             #define constants
*
**********************************************************************
*/

#define HW_USE_SPI 1

#define FS__MMC_DEFAULTSUPPLYVOLTAGE  3300 /* in mV, example means 3.3V */
#define SIO_FREQ                     12600 /* KHz, SysFreq/4            */

/*********************************************************************
*
*             #define Macros
*
**********************************************************************
*/
#define SPI_CLR_CS()          GPIOPADR &= ~(1 << 2)
#define SPI_SET_CS()          GPIOPADR |=  (1 << 2)

/*********************************************************************
*
*       Static data
*
**********************************************************************
*/
static volatile char _Dummy;

/*********************************************************************
*
*             Local functions
*
**********************************************************************
*/


static void _Init(void) {
  #ifdef HW_USE_SPI
  IOSSPMUX       |= 0x8;            // Set pins as SPI
  GPIOPADDR = (1 << 2)  /* PA2 output */
            | (1 << 1); /* PA1 output */
  PERIPHCLKCTRL2 &=  ~(1<<1);        // enable clock for SPI
  SSPCLKPRESCALE  =   1;             // prescaler /2 for SPI 
  SSCPSR          =   2;             // again prescaler /2 for SPI 
  SSPCR0          =  (1 << 8)       // Clock divisor
                    |(1  << 7)       // Clock phase   ... 1: SSPFRM = 0
                    |(1  << 6)       // Polarity
                    |(0  << 5)       // Frame format
                    |(0  << 4)       // Frame format
                    |(7  << 0);      // 8 bit data
  SSPCR1          =  (1  << 4)       // enable SPI
                    |(0  << 3)       // loopback mode
                    |(0  << 2)       // disable receive FIFO overrun interrupt
                    |(0  << 1)       // disable Transmit FIFO interrupt
                    |(0  << 1);      // disable Receive  FIFO interrupt
    _Dummy = SSPDR;
    _Dummy = SSPDR;
    _Dummy = SSPDR;
    _Dummy = SSPDR;
    _Dummy = SSPDR;
}

/*********************************************************************
*
*             FS_MMC_HW_X_BusyLedOff
*
*  Description:
*    FS low level function. Switches the busy LED off.
*
*  Parameters:
*    Unit      - Unit number
*
*  Return value:
*    void
*/
void FS_MMC_HW_X_BusyLedOff (FS_U8 Unit) {
  *((volatile unsigned char*)(0x55600000)) |= (1 << 0);
}

/*********************************************************************
*
*             FS_MMC_HW_X_BusyLedOn
*
*  Description:
*    FS low level function. Switches the busy LED off.
*
*  Parameters:
*    Unit      - Unit number
*
*  Return value:
*    void
*/

void FS_MMC_HW_X_BusyLedOn  (FS_U8 Unit) {
  *((volatile unsigned char*)(0x55600000)) &= ~(1 << 0);  
}

/*********************************************************************
*
*       FS_MMC_HW_X_EnableCS
*
*  Description:
*    FS low level function. Sets the card slot active using the
*    chip select (CS) line.
*
*  Parameters:
*    Unit      - Unit number
*
*  Return value:
*    void
*/

void FS_MMC_HW_X_EnableCS   (FS_U8 Unit) {
  SPI_CLR_CS();
}

/*********************************************************************
*
*       FS_MMC_HW_X_EnableCS
*
*  Description:
*    FS low level function. Sets the card slot inactive using the
*    chip select (CS) line.
*
*  Parameters:
*    Unit      - Unit number
*
*  Return value:
*    void
*/

void FS_MMC_HW_X_DisableCS(FS_U8 Unit) {
  SPI_SET_CS();
}

/*********************************************************************
*
*       FS_MMC_HW_X_IsWriteProtected
*
*  Description:
*    FS low level function. Returns the state of the physical write
*    protection of the SD cards.
*
*  Parameters:
*    Unit      - Unit number
*
*  Return value:
*    1                - the card is write protected
*    ==0              - the card is not write protected
*/

char FS_MMC_HW_X_IsWriteProtected(FS_U8 Unit) {
  /* If the card slot has no write switch detector, return 0 */
  return 0;
}

/*********************************************************************
*
*       FS_MMC_HW_X_SetMaxSpeed
*
*  Description:
*    FS low level function. Sets the SPI interface to a maximum frequency.
*    Make sure that you set the frequency lower or equal but never higher
*    than the given value. Recommended startup frequency is 100kHz - 400kHz.
*
*  Parameters:
*    Unit       - Unit number
*    MaxFreq    - SPI clock frequency in kHz
*
*  Return value:
*    max. frequency    - the maximum frequency set in kHz
*    ==0               - the frequency could not be set
*/

FS_U16 FS_MMC_HW_X_SetMaxSpeed(FS_U8 Unit, FS_U16 MaxFreq) {
  int Divider;
  _Init();
  SSPCR1  &= ~(1 << 4);      // Disable SPI
  Divider = SIO_FREQ / MaxFreq;
  if (Divider > 255) {
    Divider = 255;
  }
  SSPCR0  = (SSPCR0 & 0xff) | (Divider << 8);
  SSPCR1  |= (1 << 4);      // Enable SPI
  return SIO_FREQ / (Divider + 1);    /* We are not faster than this */
}

/*********************************************************************
*
*             FS_MMC_HW_X_SetVoltage
*
*  Description:
*    FS low level function. Be sure that your card slot si within the given
*    voltage range. Return 1 if your slot can support the required voltage,
*    and if not, return 0;
*
*  Parameters:
*    Unit      - Unit number
*    MaxFreq          - SPI clock frequency in kHz
*
*  Return value:
*    1                - the card slot supports the voltage range
*    ==0              - the card slot does not support the voltage range
*/

char FS_MMC_HW_X_SetVoltage(FS_U8 Unit, FS_U16 Vmin, FS_U16 Vmax) {
  char r;
  /* voltage range check */
  if((Vmin <= FS__MMC_DEFAULTSUPPLYVOLTAGE) && (Vmax >= FS__MMC_DEFAULTSUPPLYVOLTAGE)) {
    r = 1;
  } else {
    r = 0;
  }
  return r;
}

/*********************************************************************
*
*       FS_MMC_HW_X_IsPresent
*
*  Description:
*    Returns the state of the media. If you do not know the state, return
*    FS_MEDIA_STATEUNKNOWN and the higher layer will try to figure out if
*    a media is present.
*
*  Parameters:
*    Unit                 - Unit number
*
*  Return value:
*    FS_MEDIA_STATEUNKNOWN       - the state of the media is unkown
*    FS_MEDIA_ISNOTPRESENT       - no card is present
*    FS_MEDIA_ISPRESENT          - a card is present
*/

char FS_MMC_HW_X_IsPresent(FS_U8 Unit) {
  return FS_MEDIA_STATEUNKNOWN;
}

/*********************************************************************
*
*       FS_MMC_HW_X_Read
*
*  Description:
*    FS low level function. Reads a specified number of bytes from MMC
*    card to buffer.
*
*  Parameters:
*    Unit        - Unit number
*    pData       - Pointer to a data buffer
*    NumBytes    - Number of bytes
*
*  Return value:
*    void
*/

void FS_MMC_HW_X_Read (FS_U8 DevIndex, FS_U8 * pData, int NumBytes) {
#if 1
  SSPDR = 0xff;
  if (--NumBytes) {
    do {
      SSPDR = 0xff;
      while ((SSPSR & (1 << 2)) == 0);  /* Wait until we received a byte */
      *pData++ = SSPDR;
    } while (--NumBytes);
  } 
  while ((SSPSR & (1 << 2)) == 0);  /* Wait until we received a byte */
  *pData = SSPDR;
#else
  do {
    SSPDR = 0xff;
    while ((SSPSR & (1 << 2)) == 0);  /* Wait until we received a byte */
    *pData++ = SSPDR;
  } while (--NumBytes);
#endif
}

/*********************************************************************
*
*       FS_MMC_HW_X_Write
*
*  Description:
*    FS low level function. Writes a specified number of bytes from
*    data buffer to the MMC/SD card.
*
*  Parameters:
*    Unit        - Unit number
*    pData       - Pointer to a data buffer
*    NumBytes    - Number of bytes
*
*  Return value:
*    void
*/

void FS_MMC_HW_X_Write(FS_U8 Unit, const FS_U8 * pData, int NumBytes) {
  while ((SSPSR & (1 << 4)) != 0);  /* Busy ? */
  do {
    SSPDR = *pData++;
    while ((SSPSR & (1 << 2)) == 0);  /* Wait until we received a byte */
    _Dummy = SSPDR;
  } while (--NumBytes);
}

#endif /* FS_USE_MMC_DRIVER */