Diff: SDBlockDevice.h

Revision:

0:6c7012898e59

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SDBlockDevice.h	Mon Jul 23 12:22:39 2018 +0000
@@ -0,0 +1,236 @@
+/* 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 SDCard is not supported */
+#ifdef DEVICE_SPI
+
+#include "BlockDevice.h"
+#include "mbed.h"
+#include "platform/PlatformMutex.h"
+
+/** Access an SD Card using SPI
+ *
+ * @code
+ * #include "mbed.h"
+ * #include "SDBlockDevice.h"
+ *
+ * SDBlockDevice sd(p5, p6, p7, p12); // mosi, miso, sclk, cs
+ * uint8_t block[512] = "Hello World!\n";
+ *
+ * int main() {
+ *     sd.init();
+ *     sd.write(block, 0, 512);
+ *     sd.read(block, 0, 512);
+ *     printf("%s", block);
+ *     sd.deinit();
+ * }
+ */
+class SDBlockDevice : public BlockDevice {
+public:
+    /** Lifetime of an SD card
+     */
+    SDBlockDevice(PinName mosi, PinName miso, PinName sclk, PinName cs, uint64_t hz=1000000, bool crc_on=0);
+    virtual ~SDBlockDevice();
+
+    /** Initialize a block device
+     *
+     *  @return         0 on success or a negative error code on failure
+     */
+    virtual int init();
+
+    /** Deinitialize a block device
+     *
+     *  @return         0 on success or a negative error code on failure
+     */
+    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         0 on success, negative error code on failure
+     */
+    virtual int read(void *buffer, bd_addr_t addr, bd_size_t size);
+
+    /** Program blocks to a block device
+     *
+     *  The blocks must have been erased prior to being programmed
+     *
+     *  @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         0 on success, negative error code on failure
+     */
+    virtual int program(const void *buffer, bd_addr_t addr, 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         0 on success, negative error code on failure
+     */
+    virtual int trim(bd_addr_t addr, bd_size_t size);
+
+    /** Get the size of a readable block
+     *
+     *  @return         Size of a readable block in bytes
+     */
+    virtual bd_size_t get_read_size() const;
+
+    /** Get the size of a programable block
+     *
+     *  @return         Size of a programable block in bytes
+     *  @note Must be a multiple of the read size
+     */
+    virtual bd_size_t get_program_size() const;
+
+    /** Get the total size of the underlying device
+     *
+     *  @return         Size of the underlying device in bytes
+     */
+    virtual bd_size_t size() const;
+
+    /** Enable or disable debugging
+     *
+     *  @param          State of debugging
+     */
+    virtual void debug(bool dbg);
+
+    /** Set the transfer frequency
+     *
+     *  @param         Transfer frequency
+     *  @note Max frequency supported is 25MHZ
+     */
+    virtual int frequency(uint64_t freq);
+
+
+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 SDCard into the SPI Mode idle state
+     *
+     *  The card is transitioned from SDCard 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();
+
+    bd_size_t _sectors;
+    bd_size_t _sd_sectors();
+
+    bool _is_valid_trim(bd_addr_t addr, bd_size_t size);
+
+    /* SPI functions */
+    Timer _spi_timer;               /**< Timer Class object used for busy wait */
+    uint32_t _init_sck;             /**< Intial SPI frequency */
+    uint32_t _transfer_sck;         /**< SPI frequency during data transfer/after initialization */
+    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 */
+    DigitalOut _cs;
+    void _select();
+    void _deselect();
+
+    virtual void lock() {
+        _mutex.lock();
+    }
+
+    virtual void unlock() {
+        _mutex.unlock();
+    }
+
+    PlatformMutex _mutex;
+    bd_size_t _block_size;
+    bd_size_t _erase_size;
+    bool _is_initialized;
+    bool _dbg;
+    bool _crc_on;
+
+    MbedCRC<POLY_7BIT_SD, 7> _crc7;
+    MbedCRC<POLY_16BIT_CCITT, 16> _crc16;
+};
+
+#endif  /* DEVICE_SPI */
+
+#endif  /* MBED_SD_BLOCK_DEVICE_H */