Mbed OS Reference | SDBlockDevice.h Source File

 /* mbed Microcontroller Library
  * Copyright (c) 2006-2013 ARM Limited
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 
 #ifndef MBED_SD_BLOCK_DEVICE_H
 #define MBED_SD_BLOCK_DEVICE_H
 
 /* If the target has no SPI support, then SD Card is not supported. */
 #if DEVICE_SPI
 
 #include "BlockDevice.h"
 #include "drivers/SPI.h"
 #include "drivers/Timer.h"
 #include "drivers/MbedCRC.h"
 #include "drivers/DigitalOut.h"
 #include "platform/platform.h"
 #include "platform/PlatformMutex.h"
 
 /** SDBlockDevice class
  *
  * Access an SD Card using SPI bus
  */
 class SDBlockDevice : public mbed::BlockDevice {
 public:
     /** Creates an SDBlockDevice on a SPI bus specified by pins
      *
      *  @param mosi     SPI master out, slave in pin
      *  @param miso     SPI master in, slave out pin
      *  @param sclk     SPI clock pin
      *  @param cs       SPI chip select pin
      *  @param hz       Clock speed of the SPI bus (defaults to 1MHz)
      *  @param crc_on   Enable cyclic redundancy check (defaults to disabled)
      */
     SDBlockDevice(PinName mosi, PinName miso, PinName sclk, PinName cs, uint64_t hz = 1000000, bool crc_on = 0);
     virtual ~SDBlockDevice();
 
     /** Initialize a block device
      *
      *  @return         BD_ERROR_OK(0) - success
      *                  BD_ERROR_DEVICE_ERROR - device driver transaction failed
      *                  SD_BLOCK_DEVICE_ERROR_NO_DEVICE - device (SD card) is missing or not connected
      *                  SD_BLOCK_DEVICE_ERROR_UNUSABLE - unusable card
      *                  SD_BLOCK_DEVICE_ERROR_CRC - crc error
      */
     virtual int init();
 
     /** Deinitialize a block device
      *
      *  @return         BD_ERROR_OK(0) - success
      */
     virtual int deinit();
 
     /** Read blocks from a block device
      *
      *  @param buffer   Buffer to write blocks to
      *  @param addr     Address of block to begin reading from
      *  @param size     Size to read in bytes, must be a multiple of read block size
      *  @return         BD_ERROR_OK(0) - success
      *                  SD_BLOCK_DEVICE_ERROR_NO_DEVICE - device (SD card) is missing or not connected
      *                  SD_BLOCK_DEVICE_ERROR_CRC - crc error
      *                  SD_BLOCK_DEVICE_ERROR_PARAMETER - invalid parameter
      *                  SD_BLOCK_DEVICE_ERROR_NO_RESPONSE - no response from device
      *                  SD_BLOCK_DEVICE_ERROR_UNSUPPORTED - unsupported command
      */
     virtual int read(void *buffer, mbed::bd_addr_t addr, mbed::bd_size_t size);
 
     /** Program blocks to a block device
      *
      *  @note The blocks must be erased prior to programming
      *
      *  @param buffer   Buffer of data to write to blocks
      *  @param addr     Address of block to begin writing to
      *  @param size     Size to write in bytes. Must be a multiple of program block size
      *  @return         BD_ERROR_OK(0) - success
      *                  SD_BLOCK_DEVICE_ERROR_NO_DEVICE - device (SD card) is missing or not connected
      *                  SD_BLOCK_DEVICE_ERROR_CRC - crc error
      *                  SD_BLOCK_DEVICE_ERROR_PARAMETER - invalid parameter
      *                  SD_BLOCK_DEVICE_ERROR_UNSUPPORTED - unsupported command
      *                  SD_BLOCK_DEVICE_ERROR_NO_INIT - device is not initialized
      *                  SD_BLOCK_DEVICE_ERROR_WRITE - SPI write error
      *                  SD_BLOCK_DEVICE_ERROR_ERASE - erase error
      */
     virtual int program(const void *buffer, mbed::bd_addr_t addr, mbed::bd_size_t size);
 
     /** Mark blocks as no longer in use
      *
      *  This function provides a hint to the underlying block device that a region of blocks
      *  is no longer in use and may be erased without side effects. Erase must still be called
      *  before programming, but trimming allows flash-translation-layers to schedule erases when
      *  the device is not busy.
      *
      *  @param addr     Address of block to mark as unused
      *  @param size     Size to mark as unused in bytes, must be a multiple of erase block size
      *  @return         BD_ERROR_OK(0) - success
      *                  SD_BLOCK_DEVICE_ERROR_NO_DEVICE - device (SD card) is missing or not connected
      *                  SD_BLOCK_DEVICE_ERROR_CRC - crc error
      *                  SD_BLOCK_DEVICE_ERROR_PARAMETER - invalid parameter
      *                  SD_BLOCK_DEVICE_ERROR_UNSUPPORTED - unsupported command
      *                  SD_BLOCK_DEVICE_ERROR_NO_INIT - device is not initialized
      *                  SD_BLOCK_DEVICE_ERROR_ERASE - erase error
      */
     virtual int trim(mbed::bd_addr_t addr, mbed::bd_size_t size);
 
     /** Get the size of a readable block
      *
      *  @return         Size of a readable block in bytes
      */
     virtual mbed::bd_size_t get_read_size() const;
 
     /** Get the size of a programmable block
      *
      *  @return         Size of a programmable block in bytes
      *  @note Must be a multiple of the read size
      */
     virtual mbed::bd_size_t get_program_size() const;
 
     /** Get the total size of the underlying device
      *
      *  @return         Size of the underlying device in bytes
      */
     virtual mbed::bd_size_t size() const;
 
     /** Enable or disable debugging
      *
      *  @param dbg        State of debugging
      */
     virtual void debug(bool dbg);
 
     /** Set the transfer frequency
      *
      *  @param freq     Transfer frequency
      *  @note Max frequency supported is 25MHZ
      */
     virtual int frequency(uint64_t freq);
 
     /** Get the BlockDevice class type.
      *
      *  @return         A string representation of the BlockDevice class type.
      */
     virtual const char *get_type() const;
 
 private:
     /* Commands : Listed below are commands supported
      * in SPI mode for SD card : Only Mandatory ones
      */
     enum cmdSupported {
         CMD_NOT_SUPPORTED = -1,             /**< Command not supported error */
         CMD0_GO_IDLE_STATE = 0,             /**< Resets the SD Memory Card */
         CMD1_SEND_OP_COND = 1,              /**< Sends host capacity support */
         CMD6_SWITCH_FUNC = 6,               /**< Check and Switches card function */
         CMD8_SEND_IF_COND = 8,              /**< Supply voltage info */
         CMD9_SEND_CSD = 9,                  /**< Provides Card Specific data */
         CMD10_SEND_CID = 10,                /**< Provides Card Identification */
         CMD12_STOP_TRANSMISSION = 12,       /**< Forces the card to stop transmission */
         CMD13_SEND_STATUS = 13,             /**< Card responds with status */
         CMD16_SET_BLOCKLEN = 16,            /**< Length for SC card is set */
         CMD17_READ_SINGLE_BLOCK = 17,       /**< Read single block of data */
         CMD18_READ_MULTIPLE_BLOCK = 18,     /**< Card transfers data blocks to host until interrupted
                                                  by a STOP_TRANSMISSION command */
         CMD24_WRITE_BLOCK = 24,             /**< Write single block of data */
         CMD25_WRITE_MULTIPLE_BLOCK = 25,    /**< Continuously writes blocks of data until
                                                  'Stop Tran' token is sent */
         CMD27_PROGRAM_CSD = 27,             /**< Programming bits of CSD */
         CMD32_ERASE_WR_BLK_START_ADDR = 32, /**< Sets the address of the first write
                                                  block to be erased. */
         CMD33_ERASE_WR_BLK_END_ADDR = 33,   /**< Sets the address of the last write
                                                  block of the continuous range to be erased.*/
         CMD38_ERASE = 38,                   /**< Erases all previously selected write blocks */
         CMD55_APP_CMD = 55,                 /**< Extend to Applications specific commands */
         CMD56_GEN_CMD = 56,                 /**< General Purpose Command */
         CMD58_READ_OCR = 58,                /**< Read OCR register of card */
         CMD59_CRC_ON_OFF = 59,              /**< Turns the CRC option on or off*/
         // App Commands
         ACMD6_SET_BUS_WIDTH = 6,
         ACMD13_SD_STATUS = 13,
         ACMD22_SEND_NUM_WR_BLOCKS = 22,
         ACMD23_SET_WR_BLK_ERASE_COUNT = 23,
         ACMD41_SD_SEND_OP_COND = 41,
         ACMD42_SET_CLR_CARD_DETECT = 42,
         ACMD51_SEND_SCR = 51,
     };
 
     uint8_t _card_type;
     int _cmd(SDBlockDevice::cmdSupported cmd, uint32_t arg, bool isAcmd = 0, uint32_t *resp = NULL);
     int _cmd8();
 
     /*  Move the SD Card into the SPI Mode idle state
      *
      *  The card is transitioned from SD Card mode to SPI mode by sending the
      *  CMD0 (GO_IDLE_STATE) command with CS asserted. See the notes in the
      *  "SPI Startup" section of the comments at the head of the
      *  implementation file for further details and specification references.
      *
      *  @return         Response form the card. R1_IDLE_STATE (0x1), the successful
      *                  response from CMD0. R1_XXX_XXX for more response
      */
     uint32_t _go_idle_state();
     int _initialise_card();
 
     mbed::bd_size_t _sectors;
     mbed::bd_size_t _sd_sectors();
 
     bool _is_valid_trim(mbed::bd_addr_t addr, mbed::bd_size_t size);
 
     /* SPI functions */
     mbed::Timer _spi_timer;               /**< Timer Class object used for busy wait */
     uint32_t _init_sck;             /**< Initial SPI frequency */
     uint32_t _transfer_sck;         /**< SPI frequency during data transfer/after initialization */
     mbed::SPI _spi;                       /**< SPI Class object */
 
     /* SPI initialization function */
     void _spi_init();
     uint8_t _cmd_spi(SDBlockDevice::cmdSupported cmd, uint32_t arg);
     void _spi_wait(uint8_t count);
 
     bool _wait_token(uint8_t token);        /**< Wait for token */
     bool _wait_ready(uint16_t ms = 300);    /**< 300ms default wait for card to be ready */
     int _read(uint8_t *buffer, uint32_t length);
     int _read_bytes(uint8_t *buffer, uint32_t length);
     uint8_t _write(const uint8_t *buffer, uint8_t token, uint32_t length);
     int _freq(void);
 
     /* Chip Select and SPI mode select */
     mbed::DigitalOut _cs;
     void _select();
     void _deselect();
 
     virtual void lock()
     {
         _mutex.lock();
     }
 
     virtual void unlock()
     {
         _mutex.unlock();
     }
 
     PlatformMutex _mutex;
     static const uint32_t _block_size;
     uint32_t _erase_size;
     bool _is_initialized;
     bool _dbg;
     uint32_t _init_ref_count;
 
 #if MBED_CONF_SD_CRC_ENABLED
     bool _crc_on;
     mbed::MbedCRC<POLY_7BIT_SD, 7> _crc7;
     mbed::MbedCRC<POLY_16BIT_CCITT, 16> _crc16;
 #endif
 };
 
 #endif  /* DEVICE_SPI */
 
 #endif  /* MBED_SD_BLOCK_DEVICE_H */
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