text: /****************************************************************************
   * arch/arm/src/lpc17xx_40xx/lpc17_40_sdcard.c
   *
   *   Copyright (C) 2013-2014, 2016-2017 Gregory Nutt. All rights reserved.
   *   Author: Gregory Nutt <gnutt@nuttx.org>
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   * 3. Neither the name NuttX nor the names of its contributors may be
   *    used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
   * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
   * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
   * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
   * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
   * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
   * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
   * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGE.
   *
   ****************************************************************************/
  
  /****************************************************************************
   * Included Files
   ****************************************************************************/
  
  #include <nuttx/config.h>
  
  #include <stdint.h>
  #include <stdbool.h>
  #include <semaphore.h>
  #include <string.h>
  #include <assert.h>
  #include <debug.h>
  #include <errno.h>
  
  #include <nuttx/wdog.h>
  #include <nuttx/clock.h>
  #include <nuttx/arch.h>
  #include <nuttx/sdio.h>
  #include <nuttx/wqueue.h>
  #include <nuttx/semaphore.h>
  #include <nuttx/mmcsd.h>
  
  #include <nuttx/irq.h>
  #include <arch/board/board.h>
  
  #include "chip.h"
  #include "up_arch.h"
  
  #include "lpc17_40_gpdma.h"
  #include "lpc17_40_gpio.h"
  #include "lpc17_40_sdcard.h"
  
  #include "hardware/lpc17_40_syscon.h"
  #include "hardware/lpc17_40_pinconfig.h"
  
  #ifdef CONFIG_LPC17_40_SDCARD
  
  /****************************************************************************
   * Pre-processor Definitions
   ****************************************************************************/
  
  /* Configuration ************************************************************/
  /* Required system configuration options:
   *
   *   CONFIG_ARCH_DMA - Enable architecture-specific DMA subsystem
   *     initialization.  Required if CONFIG_LPC17_40_SDCARD_DMA is enabled.
   *   CONFIG_LPC17_40_GPDMA - Enable LPC17XX_40XX GPDMA support.  Required if
   *     CONFIG_LPC17_40_SDCARD_DMA is enabled
   *   CONFIG_SCHED_WORKQUEUE -- Callback support requires work queue support.
   *
   * Driver-specific configuration options:
   *
   *   CONFIG_SDIO_MUXBUS - Setting this configuration enables some locking
   *     APIs to manage concurrent accesses on the SD card bus.  This is not
   *     needed for the simple case of a single SD card, for example.
   *   CONFIG_LPC17_40_SDCARD_DMA - Enable SD card DMA.  This is a marginally optional.
   *     For most usages, SD accesses will cause data overruns if used without DMA.
   *     NOTE the above system DMA configuration options.
   *   CONFIG_LPC17_40_SDCARD_WIDTH_D1_ONLY - This may be selected to force the
   *     driver operate with only a single data line (the default is to use
   *     all 4 SD data lines).
   *   CONFIG_DEBUG_MEMCARD_* - Enables some very low-level debug output
   *     This also requires CONFIG_DEBUG_FS and CONFIG_DEBUG_INFO
   */
  
  #ifndef CONFIG_LPC17_40_SDCARD_DMA
  #  warning "Large Non-DMA transfer may result in RX overrun failures"
  #else
  #  ifndef CONFIG_LPC17_40_GPDMA
  #    error "CONFIG_LPC17_40_SDCARD_DMA support requires CONFIG_LPC17_40_GPDMA"
  #  endif
  #  ifndef CONFIG_SDIO_DMA
  #    error CONFIG_SDIO_DMA must be defined with CONFIG_LPC17_40_SDCARD_DMA
  #  endif
  #endif
  
  #ifndef CONFIG_SCHED_WORKQUEUE
  #  error "Callback support requires CONFIG_SCHED_WORKQUEUE"
  #endif
  
  /* Friendly CLKCR bit re-definitions ****************************************/
  
  /* Mode dependent settings.  These depend on clock devisor settings that must
   * be defined in the board-specific board.h header file: SDCARD_INIT_CLKDIV,
   * SDCARD_MMCXFR_CLKDIV, and SDCARD_SDXFR_CLKDIV.
   */
  
  #define LPC17_40_CLCKCR_INIT         (SDCARD_INIT_CLKDIV | SDCARD_CLOCK_WIDBUS_D1)
  #define SDCARD_CLOCK_MMCXFR       (SDCARD_MMCXFR_CLKDIV | SDCARD_CLOCK_WIDBUS_D1)
  #define SDCARD_CLOCK_SDXFR        (SDCARD_SDXFR_CLKDIV | SDCARD_CLOCK_WIDBUS_D1)
  #define SDCARD_CLOCK_SDWIDEXFR    (SDCARD_SDXFR_CLKDIV | SDCARD_CLOCK_WIDBUS_D4)
  
  /* Timing */
  
  #define SDCARD_CMDTIMEOUT         (100000)
  #define SDCARD_LONGTIMEOUT        (0x7fffffff)
  
  /* Big DTIMER setting */
  
  #define SDCARD_DTIMER_DATATIMEOUT (0x000fffff)
  
  /* DMA channel/stream configuration register settings.  The following
   * must be selected.  The DMA driver will select the remaining fields.
   *
   * - 32-bit DMA
   * - Memory increment
   * - Direction (memory-to-peripheral, peripheral-to-memory)
   * - Memory burst size (F4 only)
   */
  
  /* DMA control register settings.  All CONTROL register fields need to be
   * specified except for the transfer size which is passed as a separate
   * parameter and for the terminal count interrupt enable bit which is
   * controlled by the driver.
   */
  
  #define SDCARD_RXDMA32_CONTROL    (DMACH_CONTROL_SBSIZE_8 | DMACH_CONTROL_DBSIZE_8 | \
                                     DMACH_CONTROL_SWIDTH_32BIT | DMACH_CONTROL_DWIDTH_32BIT | \
                                     DMACH_CONTROL_DI)
  #define SDCARD_TXDMA32_CONTROL    (DMACH_CONTROL_SBSIZE_8 | DMACH_CONTROL_DBSIZE_8 | \
                                     DMACH_CONTROL_SWIDTH_32BIT | DMACH_CONTROL_DWIDTH_32BIT | \
                                     DMACH_CONTROL_SI)
  
  /* DMA configuration register settings.  Only the SRCPER, DSTPER, and
   * XFRTTYPE fields of the CONFIG register need be specified.
   */
  
  #define SDCARD_RXDMA32_CONFIG     (DMACH_CONFIG_SRCPER_SDCARD | DMACH_CONFIG_XFRTYPE_P2M_SC)
  #define SDCARD_TXDMA32_CONFIG     (DMACH_CONFIG_DSTPER_SDCARD | DMACH_CONFIG_XFRTYPE_M2P_DC)
  
  /* FIFO sizes */
  
  #define SDCARD_HALFFIFO_WORDS     (8)
  #define SDCARD_HALFFIFO_BYTES     (8*4)
  
  /* Data transfer interrupt mask bits */
  
  #define SDCARD_RECV_MASK     (SDCARD_MASK0_DCRCFAILIE | SDCARD_MASK0_DTIMEOUTIE | \
                                SDCARD_MASK0_DATAENDIE | SDCARD_MASK0_RXOVERRIE | \
                                SDCARD_MASK0_RXFIFOHFIE | SDCARD_MASK0_STBITERRIE)
  #define SDCARD_SEND_MASK     (SDCARD_MASK0_DCRCFAILIE | SDCARD_MASK0_DTIMEOUTIE | \
                                SDCARD_MASK0_DATAENDIE | SDCARD_MASK0_TXUNDERRIE | \
                                SDCARD_MASK0_TXFIFOHEIE | SDCARD_MASK0_STBITERRIE)
  #define SDCARD_DMARECV_MASK  (SDCARD_MASK0_DCRCFAILIE | SDCARD_MASK0_DTIMEOUTIE | \
                                SDCARD_MASK0_DATAENDIE | SDCARD_MASK0_RXOVERRIE | \
                                SDCARD_MASK0_STBITERRIE)
  #define SDCARD_DMASEND_MASK  (SDCARD_MASK0_DCRCFAILIE | SDCARD_MASK0_DTIMEOUTIE | \
                                SDCARD_MASK0_DATAENDIE | SDCARD_MASK0_TXUNDERRIE | \
                                SDCARD_MASK0_STBITERRIE)
  
  /* Event waiting interrupt mask bits */
  
  #define SDCARD_CMDDONE_STA   (SDCARD_STATUS_CMDSENT)
  #define SDCARD_RESPDONE_STA  (SDCARD_STATUS_CTIMEOUT | SDCARD_STATUS_CCRCFAIL | \
                                SDCARD_STATUS_CMDREND)
  #define SDCARD_XFRDONE_STA   (0)
  
  #define SDCARD_CMDDONE_MASK  (SDCARD_MASK0_CMDSENTIE)
  #define SDCARD_RESPDONE_MASK (SDCARD_MASK0_CCRCFAILIE | SDCARD_MASK0_CTIMEOUTIE | \
                                SDCARD_MASK0_CMDRENDIE)
  #define SDCARD_XFRDONE_MASK  (0)
  
  #define SDCARD_CMDDONE_ICR   (SDCARD_CLEAR_CMDSENTC)
  #define SDCARD_RESPDONE_ICR  (SDCARD_CLEAR_CTIMEOUTC | SDCARD_CLEAR_CCRCFAILC | \
                                SDCARD_CLEAR_CMDRENDC)
  #define SDCARD_XFRDONE_ICR   (SDCARD_CLEAR_DATAENDC | SDCARD_CLEAR_DCRCFAILC | \
                                SDCARD_CLEAR_DTIMEOUTC | SDCARD_CLEAR_RXOVERRC | \
                                SDCARD_CLEAR_TXUNDERRC | SDCARD_CLEAR_STBITERRC)
  
  #define SDCARD_WAITALL_ICR   (SDCARD_CMDDONE_ICR | SDCARD_RESPDONE_ICR | \
                                SDCARD_XFRDONE_ICR)
  
  /* Let's wait until we have both SD card transfer complete and DMA complete. */
  
  #define SDCARD_XFRDONE_FLAG  (1)
  #define SDCARD_DMADONE_FLAG  (2)
  #define SDCARD_ALLDONE       (3)
  
  /* Register logging support */
  
  #ifdef CONFIG_DEBUG_MEMCARD_INFO
  #  ifdef CONFIG_LPC17_40_SDCARD_DMA
  #    define SAMPLENDX_BEFORE_SETUP  0
  #    define SAMPLENDX_BEFORE_ENABLE 1
  #    define SAMPLENDX_AFTER_SETUP   2
  #    define SAMPLENDX_END_TRANSFER  3
  #    define SAMPLENDX_DMA_CALLBACK  4
  #    define DEBUG_NSAMPLES          5
  #  else
  #    define SAMPLENDX_BEFORE_SETUP  0
  #    define SAMPLENDX_AFTER_SETUP   1
  #    define SAMPLENDX_END_TRANSFER  2
  #    define DEBUG_NSAMPLES          3
  #  endif
  #endif
  
  /****************************************************************************
   * Private Types
   ****************************************************************************/
  
  /* This structure defines the state of the LPC17XX_40XX SD card interface */
  
  struct lpc17_40_dev_s
  {
    struct sdio_dev_s  dev;        /* Standard, base SD card interface */
  
    /* LPC17XX_40XX-specific extensions */
    /* Event support */
  
    sem_t              waitsem;    /* Implements event waiting */
    sdio_eventset_t    waitevents; /* Set of events to be waited for */
    uint32_t           waitmask;   /* Interrupt enables for event waiting */
    volatile sdio_eventset_t wkupevent; /* The event that caused the wakeup */
    WDOG_ID            waitwdog;   /* Watchdog that handles event timeouts */
  
    /* Callback support */
  
    sdio_statset_t     cdstatus;   /* Card status */
    sdio_eventset_t    cbevents;   /* Set of events to be cause callbacks */
    worker_t           callback;   /* Registered callback function */
    void              *cbarg;      /* Registered callback argument */
    struct work_s      cbwork;     /* Callback work queue structure */
  
    /* Interrupt mode data transfer support */
  
    uint32_t          *buffer;     /* Address of current R/W buffer */
    size_t             remaining;  /* Number of bytes remaining in the transfer */
    uint32_t           xfrmask;    /* Interrupt enables for data transfer */
  
    /* DMA data transfer support */
  
    bool               widebus;    /* Required for DMA support */
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
    volatile uint8_t   xfrflags;   /* Used to synchronize SD card and DMA completion events */
    bool               dmamode;    /* true: DMA mode transfer */
    DMA_HANDLE         dma;        /* Handle for DMA channel */
  #endif
  };
  
  /* Register logging support */
  
  #ifdef CONFIG_DEBUG_MEMCARD_INFO
  struct lpc17_40_sdcard_regs_s
  {
    uint8_t  pwr;
    uint16_t clkcr;
    uint16_t dctrl;
    uint32_t dtimer;
    uint32_t dlen;
    uint32_t dcount;
    uint32_t sta;
    uint32_t mask;
    uint32_t fifocnt;
  };
  
  struct lpc17_40_sampleregs_s
  {
    struct lpc17_40_sdcard_regs_s sdcard;
  #if defined(CONFIG_DEBUG_DMA) && defined(CONFIG_LPC17_40_SDCARD_DMA)
    struct lpc17_40_dmaregs_s  dma;
  #endif
  };
  #endif
  
  /****************************************************************************
   * Private Function Prototypes
   ****************************************************************************/
  
  /* Low-level helpers ********************************************************/
  
  static void lpc17_40_takesem(struct lpc17_40_dev_s *priv);
  #define     lpc17_40_givesem(priv) (nxsem_post(&priv->waitsem))
  static inline void lpc17_40_setclock(uint32_t clkcr);
  static void lpc17_40_configwaitints(struct lpc17_40_dev_s *priv, uint32_t waitmask,
                sdio_eventset_t waitevents, sdio_eventset_t wkupevents);
  static void lpc17_40_configxfrints(struct lpc17_40_dev_s *priv, uint32_t xfrmask);
  static void lpc17_40_setpwrctrl(uint32_t pwrctrl);
  static inline uint32_t lpc17_40_getpwrctrl(void);
  
  /* DMA Helpers **************************************************************/
  
  #ifdef CONFIG_DEBUG_MEMCARD_INFO
  static void lpc17_40_sampleinit(void);
  static void lpc17_40_sdcard_sample(struct lpc17_40_sdcard_regs_s *regs);
  static void lpc17_40_sample(struct lpc17_40_dev_s *priv, int index);
  static void lpc17_40_sdcard_dump(struct lpc17_40_sdcard_regs_s *regs, const char *msg);
  static void lpc17_40_dumpsample(struct lpc17_40_dev_s *priv,
                struct lpc17_40_sampleregs_s *regs, const char *msg);
  static void lpc17_40_dumpsamples(struct lpc17_40_dev_s *priv);
  #else
  #  define   lpc17_40_sampleinit()
  #  define   lpc17_40_sample(priv,index)
  #  define   lpc17_40_dumpsamples(priv)
  #endif
  
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
  static void lpc17_40_dmacallback(DMA_HANDLE handle, void *arg, int status);
  #endif
  
  /* Data Transfer Helpers ****************************************************/
  
  static uint8_t lpc17_40_log2(uint16_t value);
  static void lpc17_40_dataconfig(uint32_t timeout, uint32_t dlen, uint32_t dctrl);
  static void lpc17_40_datadisable(void);
  static void lpc17_40_sendfifo(struct lpc17_40_dev_s *priv);
  static void lpc17_40_recvfifo(struct lpc17_40_dev_s *priv);
  static void lpc17_40_eventtimeout(int argc, uint32_t arg);
  static void lpc17_40_endwait(struct lpc17_40_dev_s *priv, sdio_eventset_t wkupevent);
  static void lpc17_40_endtransfer(struct lpc17_40_dev_s *priv, sdio_eventset_t wkupevent);
  
  /* Interrupt Handling *******************************************************/
  
  static int  lpc17_40_interrupt(int irq, void *context, FAR void *arg);
  
  /* SD Card Interface Methods ************************************************/
  
  /* Mutual exclusion */
  
  #ifdef CONFIG_SDIO_MUXBUS
  static int lpc17_40_lock(FAR struct sdio_dev_s *dev, bool lock);
  #endif
  
  /* Initialization/setup */
  
  static void lpc17_40_reset(FAR struct sdio_dev_s *dev);
  static sdio_capset_t lpc17_40_capabilities(FAR struct sdio_dev_s *dev);
  static uint8_t lpc17_40_status(FAR struct sdio_dev_s *dev);
  static void lpc17_40_widebus(FAR struct sdio_dev_s *dev, bool enable);
  static void lpc17_40_clock(FAR struct sdio_dev_s *dev,
                enum sdio_clock_e rate);
  static int  lpc17_40_attach(FAR struct sdio_dev_s *dev);
  
  /* Command/Status/Data Transfer */
  
  static int  lpc17_40_sendcmd(FAR struct sdio_dev_s *dev, uint32_t cmd,
                uint32_t arg);
  static int  lpc17_40_recvsetup(FAR struct sdio_dev_s *dev, FAR uint8_t *buffer,
                size_t nbytes);
  static int  lpc17_40_sendsetup(FAR struct sdio_dev_s *dev,
                FAR const uint8_t *buffer, uint32_t nbytes);
  static int  lpc17_40_cancel(FAR struct sdio_dev_s *dev);
  
  static int  lpc17_40_waitresponse(FAR struct sdio_dev_s *dev, uint32_t cmd);
  static int  lpc17_40_recvshortcrc(FAR struct sdio_dev_s *dev, uint32_t cmd,
                uint32_t *rshort);
  static int  lpc17_40_recvlong(FAR struct sdio_dev_s *dev, uint32_t cmd,
                uint32_t rlong[4]);
  static int  lpc17_40_recvshort(FAR struct sdio_dev_s *dev, uint32_t cmd,
                uint32_t *rshort);
  static int  lpc17_40_recvnotimpl(FAR struct sdio_dev_s *dev, uint32_t cmd,
                uint32_t *rnotimpl);
  
  /* EVENT handler */
  
  static void lpc17_40_waitenable(FAR struct sdio_dev_s *dev,
                sdio_eventset_t eventset);
  static sdio_eventset_t
              lpc17_40_eventwait(FAR struct sdio_dev_s *dev, uint32_t timeout);
  static void lpc17_40_callbackenable(FAR struct sdio_dev_s *dev,
                sdio_eventset_t eventset);
  static int  lpc17_40_registercallback(FAR struct sdio_dev_s *dev,
                worker_t callback, void *arg);
  
  /* DMA */
  
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
  static int  lpc17_40_dmarecvsetup(FAR struct sdio_dev_s *dev,
                FAR uint8_t *buffer, size_t buflen);
  static int  lpc17_40_dmasendsetup(FAR struct sdio_dev_s *dev,
                FAR const uint8_t *buffer, size_t buflen);
  #endif
  
  /* Initialization/uninitialization/reset ************************************/
  
  static void lpc17_40_callback(void *arg);
  static void lpc17_40_default(void);
  
  /****************************************************************************
   * Private Data
   ****************************************************************************/
  
  struct lpc17_40_dev_s g_scard_dev =
  {
    .dev =
    {
  #ifdef CONFIG_SDIO_MUXBUS
      .lock             = lpc17_40_lock,
  #endif
      .reset            = lpc17_40_reset,
      .capabilities     = lpc17_40_capabilities,
      .status           = lpc17_40_status,
      .widebus          = lpc17_40_widebus,
      .clock            = lpc17_40_clock,
      .attach           = lpc17_40_attach,
      .sendcmd          = lpc17_40_sendcmd,
      .recvsetup        = lpc17_40_recvsetup,
      .sendsetup        = lpc17_40_sendsetup,
      .cancel           = lpc17_40_cancel,
      .waitresponse     = lpc17_40_waitresponse,
      .recvR1           = lpc17_40_recvshortcrc,
      .recvR2           = lpc17_40_recvlong,
      .recvR3           = lpc17_40_recvshort,
      .recvR4           = lpc17_40_recvnotimpl,
      .recvR5           = lpc17_40_recvnotimpl,
      .recvR6           = lpc17_40_recvshortcrc,
      .recvR7           = lpc17_40_recvshort,
      .waitenable       = lpc17_40_waitenable,
      .eventwait        = lpc17_40_eventwait,
      .callbackenable   = lpc17_40_callbackenable,
      .registercallback = lpc17_40_registercallback,
  #ifdef CONFIG_SDIO_DMA
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
      .dmarecvsetup     = lpc17_40_dmarecvsetup,
      .dmasendsetup     = lpc17_40_dmasendsetup,
  #else
      .dmarecvsetup     = lpc17_40_recvsetup,
      .dmasendsetup     = lpc17_40_sendsetup,
  #endif
  #endif
    },
  };
  
  /* Register logging support */
  
  #ifdef CONFIG_DEBUG_MEMCARD_INFO
  static struct lpc17_40_sampleregs_s g_sampleregs[DEBUG_NSAMPLES];
  #endif
  
  /****************************************************************************
   * Private Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Low-level Helpers
   ****************************************************************************/
  /****************************************************************************
   * Name: lpc17_40_takesem
   *
   * Description:
   *   Take the wait semaphore (handling false alarm wakeups due to the receipt
   *   of signals).
   *
   * Input Parameters:
   *   dev - Instance of the SD card device driver state structure.
   *
   * Returned Value:
   *   None
   *
   ****************************************************************************/
  
  static void lpc17_40_takesem(struct lpc17_40_dev_s *priv)
  {
    int ret;
  
    do
      {
        /* Take the semaphore (perhaps waiting) */
  
        ret = nxsem_wait(&priv->waitsem);
  
        /* The only case that an error should occur here is if the wait was
         * awakened by a signal.
         */
  
        DEBUGASSERT(ret == OK || ret == -EINTR);
      }
    while (ret == -EINTR);
  }
  
  /****************************************************************************
   * Name: lpc17_40_setclock
   *
   * Description:
   *   Modify oft-changed bits in the CLKCR register.  Only the following bit-
   *   fields are changed:
   *
   *   CLKDIV, PWRSAV, BYPASS, and WIDBUS
   *
   * Input Parameters:
   *   clkcr - A new CLKCR setting for the above mentions bits (other bits
   *           are ignored.
   *
   * Returned Value:
   *   None
   *
   ****************************************************************************/
  
  static inline void lpc17_40_setclock(uint32_t clkcr)
  {
    uint32_t regval = getreg32(LPC17_40_SDCARD_CLOCK);
  
    /* Clear CLKDIV, PWRSAV, BYPASS, and WIDBUS bits */
  
    regval &= ~(SDCARD_CLOCK_CLKDIV_MASK | SDCARD_CLOCK_PWRSAV |
                SDCARD_CLOCK_BYPASS | SDCARD_CLOCK_WIDBUS |
                SDCARD_CLOCK_CLKEN);
  
    /* Replace with user provided settings */
  
    clkcr  &=  (SDCARD_CLOCK_CLKDIV_MASK | SDCARD_CLOCK_PWRSAV |
                SDCARD_CLOCK_BYPASS | SDCARD_CLOCK_WIDBUS |
                SDCARD_CLOCK_CLKEN);
  
    regval |=  clkcr;
    putreg32(regval, LPC17_40_SDCARD_CLOCK);
  
    mcinfo("CLKCR: %08x PWR: %08x\n",
           getreg32(LPC17_40_SDCARD_CLOCK), getreg32(LPC17_40_SDCARD_PWR));
  }
  
  /****************************************************************************
   * Name: lpc17_40_configwaitints
   *
   * Description:
   *   Enable/disable SD card interrupts needed to suport the wait function
   *
   * Input Parameters:
   *   priv       - A reference to the SD card device state structure
   *   waitmask   - The set of bits in the SD card MASK register to set
   *   waitevents - Waited for events
   *   wkupevent  - Wake-up events
   *
   * Returned Value:
   *   None
   *
   ****************************************************************************/
  
  static void lpc17_40_configwaitints(struct lpc17_40_dev_s *priv, uint32_t waitmask,
                                   sdio_eventset_t waitevents,
                                   sdio_eventset_t wkupevent)
  {
    irqstate_t flags;
  
    /* Save all of the data and set the new interrupt mask in one, atomic
     * operation.
     */
  
    flags = enter_critical_section();
    priv->waitevents = waitevents;
    priv->wkupevent  = wkupevent;
    priv->waitmask   = waitmask;
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
    priv->xfrflags   = 0;
  #endif
    putreg32(priv->xfrmask | priv->waitmask, LPC17_40_SDCARD_MASK0);
    leave_critical_section(flags);
  }
  
  /****************************************************************************
   * Name: lpc17_40_configxfrints
   *
   * Description:
   *   Enable SD card interrupts needed to support the data transfer event
   *
   * Input Parameters:
   *   priv    - A reference to the SD card device state structure
   *   xfrmask - The set of bits in the SD card MASK register to set
   *
   * Returned Value:
   *   None
   *
   ****************************************************************************/
  
  static void lpc17_40_configxfrints(struct lpc17_40_dev_s *priv, uint32_t xfrmask)
  {
    irqstate_t flags;
    flags = enter_critical_section();
    priv->xfrmask = xfrmask;
    putreg32(priv->xfrmask | priv->waitmask, LPC17_40_SDCARD_MASK0);
    leave_critical_section(flags);
  }
  
  /****************************************************************************
   * Name: lpc17_40_setpwrctrl
   *
   * Description:
   *   Change the PWRCTRL field of the SD card POWER register to turn the SD card
   *   ON or OFF
   *
   * Input Parameters:
   *   clkcr - A new PWRCTRL setting
   *
   * Returned Value:
   *   None
   *
   ****************************************************************************/
  
  static void lpc17_40_setpwrctrl(uint32_t pwrctrl)
  {
    uint32_t regval;
  
    /* Set the new value of the PWRCTRL field of the PWR register.  Also, as a
     * side-effect, clear the OPENDRAIN and ROD bits as well.
     */
  
    regval  = getreg32(LPC17_40_SDCARD_PWR);
    regval &= ~(SDCARD_PWR_CTRL_MASK | SDCARD_PWR_OPENDRAIN | SDCARD_PWR_ROD);
    regval |= pwrctrl;
    putreg32(regval, LPC17_40_SDCARD_PWR);
  }
  
  /****************************************************************************
   * Name: lpc17_40_getpwrctrl
   *
   * Description:
   *   Return the current value of the  the PWRCTRL field of the SD card P
   *   register.  This function can be used to see if the SD card is powered ON
   *   or OFF
   *
   * Input Parameters:
   *   None
   *
   * Returned Value:
   *   The current value of the  the PWRCTRL field of the SD card PWR register.
   *
   ****************************************************************************/
  
  static inline uint32_t lpc17_40_getpwrctrl(void)
  {
    /* Extract and return the PWRCTRL field of the PWR register. */
  
    return getreg32(LPC17_40_SDCARD_PWR) & SDCARD_PWR_CTRL_MASK;
  }
  
  /****************************************************************************
   * DMA Helpers
   ****************************************************************************/
  
  /****************************************************************************
   * Name: lpc17_40_sampleinit
   *
   * Description:
   *   Setup prior to collecting DMA samples
   *
   ****************************************************************************/
  
  #ifdef CONFIG_DEBUG_MEMCARD_INFO
  static void lpc17_40_sampleinit(void)
  {
    memset(g_sampleregs, 0xff, DEBUG_NSAMPLES * sizeof(struct lpc17_40_sampleregs_s));
  }
  #endif
  
  /****************************************************************************
   * Name: lpc17_40_sdcard_sample
   *
   * Description:
   *   Sample SD card registers
   *
   ****************************************************************************/
  
  #ifdef CONFIG_DEBUG_MEMCARD_INFO
  static void lpc17_40_sdcard_sample(struct lpc17_40_sdcard_regs_s *regs)
  {
    regs->pwr     = (uint8_t)getreg32(LPC17_40_SDCARD_PWR);
    regs->clkcr   = (uint16_t)getreg32(LPC17_40_SDCARD_CLOCK);
    regs->dctrl   = (uint16_t)getreg32(LPC17_40_SDCARD_DCTRL);
    regs->dtimer  = getreg32(LPC17_40_SDCARD_DTIMER);
    regs->dlen    = getreg32(LPC17_40_SDCARD_DLEN);
    regs->dcount  = getreg32(LPC17_40_SDCARD_DCOUNT);
    regs->sta     = getreg32(LPC17_40_SDCARD_STATUS);
    regs->mask    = getreg32(LPC17_40_SDCARD_MASK0);
    regs->fifocnt = getreg32(LPC17_40_SDCARD_FIFOCNT);
  }
  #endif
  
  /****************************************************************************
   * Name: lpc17_40_sample
   *
   * Description:
   *   Sample SD card/DMA registers
   *
   ****************************************************************************/
  
  #ifdef CONFIG_DEBUG_MEMCARD_INFO
  static void lpc17_40_sample(struct lpc17_40_dev_s *priv, int index)
  {
    struct lpc17_40_sampleregs_s *regs = &g_sampleregs[index];
  #if defined(CONFIG_DEBUG_DMA) && defined(CONFIG_LPC17_40_SDCARD_DMA)
    if (priv->dmamode)
      {
        lpc17_40_dmasample(priv->dma, &regs->dma);
      }
  #endif
  
    lpc17_40_sdcard_sample(&regs->sdcard);
  }
  #endif
  
  /****************************************************************************
   * Name: lpc17_40_sdcard_dump
   *
   * Description:
   *   Dump one register sample
   *
   ****************************************************************************/
  
  #ifdef CONFIG_DEBUG_MEMCARD_INFO
  static void lpc17_40_sdcard_dump(struct lpc17_40_sdcard_regs_s *regs, const char *msg)
  {
    mcinfo("SD Card Registers: %s\n", msg);
    mcinfo("  POWER[%08x]: %08x\n", LPC17_40_SDCARD_PWR,     regs->pwr);
    mcinfo("  CLKCR[%08x]: %08x\n", LPC17_40_SDCARD_CLOCK,   regs->clkcr);
    mcinfo("  DCTRL[%08x]: %08x\n", LPC17_40_SDCARD_DCTRL,   regs->dctrl);
    mcinfo(" DTIMER[%08x]: %08x\n", LPC17_40_SDCARD_DTIMER,  regs->dtimer);
    mcinfo("   DLEN[%08x]: %08x\n", LPC17_40_SDCARD_DLEN,    regs->dlen);
    mcinfo(" DCOUNT[%08x]: %08x\n", LPC17_40_SDCARD_DCOUNT,  regs->dcount);
    mcinfo("    STA[%08x]: %08x\n", LPC17_40_SDCARD_STATUS,  regs->sta);
    mcinfo("   MASK[%08x]: %08x\n", LPC17_40_SDCARD_MASK0,   regs->mask);
    mcinfo("FIFOCNT[%08x]: %08x\n", LPC17_40_SDCARD_FIFOCNT, regs->fifocnt);
  }
  #endif
  
  /****************************************************************************
   * Name: lpc17_40_dumpsample
   *
   * Description:
   *   Dump one register sample
   *
   ****************************************************************************/
  
  #ifdef CONFIG_DEBUG_MEMCARD_INFO
  static void lpc17_40_dumpsample(struct lpc17_40_dev_s *priv,
                               struct lpc17_40_sampleregs_s *regs, const char *msg)
  {
  #if defined(CONFIG_DEBUG_DMA) && defined(CONFIG_LPC17_40_SDCARD_DMA)
    if (priv->dmamode)
      {
        lpc17_40_dmadump(priv->dma, &regs->dma, msg);
      }
  #endif
    lpc17_40_sdcard_dump(&regs->sdcard, msg);
  }
  #endif
  
  /****************************************************************************
   * Name: lpc17_40_dumpsamples
   *
   * Description:
   *   Dump all sampled register data
   *
   ****************************************************************************/
  
  #ifdef CONFIG_DEBUG_MEMCARD_INFO
  static void lpc17_40_dumpsamples(struct lpc17_40_dev_s *priv)
  {
    lpc17_40_dumpsample(priv, &g_sampleregs[SAMPLENDX_BEFORE_SETUP], "Before setup");
  #if defined(CONFIG_DEBUG_DMA) && defined(CONFIG_LPC17_40_SDCARD_DMA)
    if (priv->dmamode)
      {
        lpc17_40_dumpsample(priv, &g_sampleregs[SAMPLENDX_BEFORE_ENABLE], "Before DMA enable");
      }
  #endif
    lpc17_40_dumpsample(priv, &g_sampleregs[SAMPLENDX_AFTER_SETUP], "After setup");
    lpc17_40_dumpsample(priv, &g_sampleregs[SAMPLENDX_END_TRANSFER], "End of transfer");
  #if defined(CONFIG_DEBUG_DMA) && defined(CONFIG_LPC17_40_SDCARD_DMA)
    if (priv->dmamode)
      {
        lpc17_40_dumpsample(priv, &g_sampleregs[SAMPLENDX_DMA_CALLBACK], "DMA Callback");
      }
  #endif
  }
  #endif
  
  /****************************************************************************
   * Name: lpc17_40_dmacallback
   *
   * Description:
   *   Called when SD card DMA completes
   *
   ****************************************************************************/
  
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
  static void lpc17_40_dmacallback(DMA_HANDLE handle, void *arg, int status)
  {
    FAR struct lpc17_40_dev_s *priv = (FAR struct lpc17_40_dev_s *)arg;
    DEBUGASSERT(priv->dmamode);
    sdio_eventset_t result;
  
    /* In the normal case, SD card appears to handle the End-Of-Transfer interrupt
     * first with the End-Of-DMA event occurring significantly later.  On
     * transfer errors, however, the DMA error will occur before the End-of-
     * Transfer.
     */
  
    lpc17_40_sample((struct lpc17_40_dev_s *)arg, SAMPLENDX_DMA_CALLBACK);
  
    /* Get the result of the DMA transfer */
  
    if (status < 0)
      {
        dmaerr("ERROR: DMA error %d, remaining: %d\n", status, priv->remaining);
        result = SDIOWAIT_ERROR;
      }
    else
      {
        result = SDIOWAIT_TRANSFERDONE;
      }
  
    /* Then terminate the transfer if this completes all of the steps in the
     * transfer OR if a DMA error occurred.  In the non-error case, we should
     * already have the SD card transfer done interrupt.  If not, the transfer
     * will appropriately time out.
     */
  
    priv->xfrflags |= SDCARD_DMADONE_FLAG;
    if (priv->xfrflags == SDCARD_ALLDONE || result == SDIOWAIT_ERROR)
      {
        lpc17_40_endtransfer(priv, result);
      }
  }
  #endif
  
  /****************************************************************************
   * Data Transfer Helpers
   ****************************************************************************/
  
  /****************************************************************************
   * Name: lpc17_40_log2
   *
   * Description:
   *   Take (approximate) log base 2 of the provided number (Only works if the
   *   provided number is a power of 2).
   *
   ****************************************************************************/
  
  static uint8_t lpc17_40_log2(uint16_t value)
  {
    uint8_t log2 = 0;
  
    /* 0000 0000 0000 0001 -> return 0,
     * 0000 0000 0000 001x -> return 1,
     * 0000 0000 0000 01xx -> return 2,
     * 0000 0000 0000 1xxx -> return 3,
     * ...
     * 1xxx xxxx xxxx xxxx -> return 15,
     */
  
    DEBUGASSERT(value > 0);
    while (value != 1)
      {
        value >>= 1;
        log2++;
      }
  
    return log2;
  }
  
  /****************************************************************************
   * Name: lpc17_40_dataconfig
   *
   * Description:
   *   Configure the SD card data path for the next data transfer
   *
   ****************************************************************************/
  
  static void lpc17_40_dataconfig(uint32_t timeout, uint32_t dlen, uint32_t dctrl)
  {
    uint32_t regval = 0;
  
    /* Enable data path */
  
    putreg32(timeout, LPC17_40_SDCARD_DTIMER); /* Set DTIMER */
    putreg32(dlen,    LPC17_40_SDCARD_DLEN);   /* Set DLEN */
  
    /* Configure DCTRL DTDIR, DTMODE, and DBLOCKSIZE fields and set the DTEN
     * field
     */
  
    regval  =  getreg32(LPC17_40_SDCARD_DCTRL);
    regval &= ~(SDCARD_DCTRL_DTDIR | SDCARD_DCTRL_DTMODE |
                SDCARD_DCTRL_DBLOCKSIZE_MASK);
    dctrl  &=  (SDCARD_DCTRL_DTDIR | SDCARD_DCTRL_DTMODE |
                SDCARD_DCTRL_DBLOCKSIZE_MASK);
    regval |=  (dctrl | SDCARD_DCTRL_DTEN);
    putreg32(regval, LPC17_40_SDCARD_DCTRL);
  }
  
  /****************************************************************************
   * Name: lpc17_40_datadisable
   *
   * Description:
   *   Disable the SD card data path setup by lpc17_40_dataconfig() and
   *   disable DMA.
   *
   ****************************************************************************/
  
  static void lpc17_40_datadisable(void)
  {
    uint32_t regval;
  
    /* Disable the data path */
  
    putreg32(SDCARD_DTIMER_DATATIMEOUT, LPC17_40_SDCARD_DTIMER); /* Reset DTIMER */
    putreg32(0,                         LPC17_40_SDCARD_DLEN);   /* Reset DLEN */
  
    /* Reset DCTRL DTEN, DTDIR, DTMODE, DMAEN, and DBLOCKSIZE fields */
  
    regval  = getreg32(LPC17_40_SDCARD_DCTRL);
    regval &= ~(SDCARD_DCTRL_DTEN | SDCARD_DCTRL_DTDIR | SDCARD_DCTRL_DTMODE |
                SDCARD_DCTRL_DMAEN | SDCARD_DCTRL_DBLOCKSIZE_MASK);
    putreg32(regval, LPC17_40_SDCARD_DCTRL);
  }
  
  /****************************************************************************
   * Name: lpc17_40_sendfifo
   *
   * Description:
   *   Send SD card data in interrupt mode
   *
   * Input Parameters:
   *   priv - An instance of the SD card device interface
   *
   * Returned Value:
   *   None
   *
   ****************************************************************************/
  
  static void lpc17_40_sendfifo(struct lpc17_40_dev_s *priv)
  {
    union
    {
      uint32_t w;
      uint8_t  b[4];
    } data;
  
    /* Loop while there is more data to be sent and the RX FIFO is not full */
  
    while (priv->remaining > 0 &&
           (getreg32(LPC17_40_SDCARD_STATUS) & SDCARD_STATUS_TXFIFOF) == 0)
      {
        /* Is there a full word remaining in the user buffer? */
  
        if (priv->remaining >= sizeof(uint32_t))
          {
            /* Yes, transfer the word to the TX FIFO */
  
            data.w           = *priv->buffer++;
            priv->remaining -= sizeof(uint32_t);
          }
        else
          {
            /* No.. transfer just the bytes remaining in the user buffer,
             * padding with zero as necessary to extend to a full word.
             */
  
            uint8_t *ptr = (uint8_t *)priv->remaining;
            int i;
  
            data.w = 0;
            for (i = 0; i < priv->remaining; i++)
              {
                 data.b[i] = *ptr++;
              }
  
            /* Now the transfer is finished */
  
            priv->remaining = 0;
          }
  
        /* Put the word in the FIFO */
  
        putreg32(data.w, LPC17_40_SDCARD_FIFO);
      }
  }
  
  /****************************************************************************
   * Name: lpc17_40_recvfifo
   *
   * Description:
   *   Receive SD card data in interrupt mode
   *
   * Input Parameters:
   *   priv - An instance of the SD card device interface
   *
   * Returned Value:
   *   None
   *
   ****************************************************************************/
  
  static void lpc17_40_recvfifo(struct lpc17_40_dev_s *priv)
  {
    union
    {
      uint32_t w;
      uint8_t  b[4];
    } data;
  
    /* Loop while there is space to store the data and there is more
     * data available in the RX FIFO.
     */
  
    while (priv->remaining > 0 &&
           (getreg32(LPC17_40_SDCARD_STATUS) & SDCARD_STATUS_RXDAVL) != 0)
      {
        /* Read the next word from the RX FIFO */
  
        data.w = getreg32(LPC17_40_SDCARD_FIFO);
        if (priv->remaining >= sizeof(uint32_t))
          {
            /* Transfer the whole word to the user buffer */
  
            *priv->buffer++  = data.w;
            priv->remaining -= sizeof(uint32_t);
          }
        else
          {
            /* Transfer any trailing fractional word */
  
            uint8_t *ptr = (uint8_t *)priv->buffer;
            int i;
  
            for (i = 0; i < priv->remaining; i++)
              {
                 *ptr++ = data.b[i];
              }
  
            /* Now the transfer is finished */
  
            priv->remaining = 0;
          }
      }
  }
  
  /****************************************************************************
   * Name: lpc17_40_eventtimeout
   *
   * Description:
   *   The watchdog timeout setup when the event wait start has expired without
   *   any other waited-for event occurring.
   *
   * Input Parameters:
   *   argc   - The number of arguments (should be 1)
   *   arg    - The argument (state structure reference cast to uint32_t)
   *
   * Returned Value:
   *   None
   *
   * Assumptions:
   *   Always called from the interrupt level with interrupts disabled.
   *
   ****************************************************************************/
  
  static void lpc17_40_eventtimeout(int argc, uint32_t arg)
  {
    struct lpc17_40_dev_s *priv = (struct lpc17_40_dev_s *)arg;
  
    /* There is always race conditions with timer expirations. */
  
    DEBUGASSERT((priv->waitevents & SDIOWAIT_TIMEOUT) != 0 || priv->wkupevent != 0);
  
    /* Is a data transfer complete event expected? */
  
    if ((priv->waitevents & SDIOWAIT_TIMEOUT) != 0)
      {
        /* Yes.. wake up any waiting threads */
  
        lpc17_40_endwait(priv, SDIOWAIT_TIMEOUT);
        mcerr("ERROR: Timeout: remaining: %d\n", priv->remaining);
      }
  }
  
  /****************************************************************************
   * Name: lpc17_40_endwait
   *
   * Description:
   *   Wake up a waiting thread if the waited-for event has occurred.
   *
   * Input Parameters:
   *   priv      - An instance of the SD card device interface
   *   wkupevent - The event that caused the wait to end
   *
   * Returned Value:
   *   None
   *
   * Assumptions:
   *   Always called from the interrupt level with interrupts disabled.
   *
   ****************************************************************************/
  
  static void lpc17_40_endwait(struct lpc17_40_dev_s *priv, sdio_eventset_t wkupevent)
  {
    /* Cancel the watchdog timeout */
  
    (void)wd_cancel(priv->waitwdog);
  
    /* Disable event-related interrupts */
  
    lpc17_40_configwaitints(priv, 0, 0, wkupevent);
  
    /* Wake up the waiting thread */
  
    lpc17_40_givesem(priv);
  }
  
  /****************************************************************************
   * Name: lpc17_40_endtransfer
   *
   * Description:
   *   Terminate a transfer with the provided status.  This function is called
   *   only from the SD card interrupt handler when end-of-transfer conditions
   *   are detected.
   *
   * Input Parameters:
   *   priv   - An instance of the SD card device interface
   *   wkupevent - The event that caused the transfer to end
   *
   * Returned Value:
   *   None
   *
   * Assumptions:
   *   Always called from the interrupt level with interrupts disabled.
   *
   ****************************************************************************/
  
  static void lpc17_40_endtransfer(struct lpc17_40_dev_s *priv, sdio_eventset_t wkupevent)
  {
    /* Disable all transfer related interrupts */
  
    lpc17_40_configxfrints(priv, 0);
  
    /* Clearing pending interrupt status on all transfer related interrupts */
  
    putreg32(SDCARD_XFRDONE_ICR, LPC17_40_SDCARD_CLEAR);
  
    /* If this was a DMA transfer, make sure that DMA is stopped */
  
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
    if (priv->dmamode)
      {
        /* DMA debug instrumentation */
  
        lpc17_40_sample(priv, SAMPLENDX_END_TRANSFER);
  
        /* Make sure that the DMA is stopped (it will be stopped automatically
         * on normal transfers, but not necessarily when the transfer terminates
         * on an error condition).
         */
  
        lpc17_40_dmastop(priv->dma);
      }
  #endif
  
    /* Mark the transfer finished */
  
    priv->remaining = 0;
  
    /* Is a thread wait for these data transfer complete events? */
  
    if ((priv->waitevents & wkupevent) != 0)
      {
        /* Yes.. wake up any waiting threads */
  
        lpc17_40_endwait(priv, wkupevent);
      }
  }
  
  /****************************************************************************
   * Interrupt Handling
   ****************************************************************************/
  
  /****************************************************************************
   * Name: lpc17_40_interrupt
   *
   * Description:
   *   SD card interrupt handler
   *
   * Input Parameters:
   *   dev - An instance of the SD card device interface
   *
   * Returned Value:
   *   None
   *
   ****************************************************************************/
  
  static int lpc17_40_interrupt(int irq, void *context, FAR void *arg)
  {
    struct lpc17_40_dev_s *priv = &g_scard_dev;
    uint32_t enabled;
    uint32_t pending;
  
    /* Loop while there are pending interrupts.  Check the SD card status
     * register.  Mask out all bits that don't correspond to enabled
     * interrupts.  (This depends on the fact that bits are ordered
     * the same in both the STA and MASK register).  If there are non-zero
     * bits remaining, then we have work to do here.
     */
  
    while ((enabled = getreg32(LPC17_40_SDCARD_STATUS) & getreg32(LPC17_40_SDCARD_MASK0)) != 0)
      {
        /* Handle in progress, interrupt driven data transfers ****************/
  
        pending  = enabled & priv->xfrmask;
        if (pending != 0)
          {
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
            if (!priv->dmamode)
  #endif
              {
                /* Is the RX FIFO half full or more?  Is so then we must be
                 * processing a receive transaction.
                */
  
                if ((pending & SDCARD_STATUS_RXFIFOHF) != 0)
                  {
                    /* Receive data from the RX FIFO */
  
                    lpc17_40_recvfifo(priv);
                  }
  
                /* Otherwise, Is the transmit FIFO half empty or less?  If so we must
                 * be processing a send transaction.  NOTE:  We can't be processing
                 * both!
                 */
  
                else if ((pending & SDCARD_STATUS_TXFIFOHE) != 0)
                  {
                    /* Send data via the TX FIFO */
  
                    lpc17_40_sendfifo(priv);
                  }
              }
  
            /* Handle data end events */
  
            if ((pending & SDCARD_STATUS_DATAEND) != 0)
              {
                /* Handle any data remaining the RX FIFO.  If the RX FIFO is
                 * less than half full at the end of the transfer, then no
                 * half-full interrupt will be received.
                 */
  
                /* Was this transfer performed in DMA mode? */
  
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
                if (priv->dmamode)
                  {
                    /* Yes.. Terminate the transfers only if the DMA has also
                     * finished.
                     */
  
                    priv->xfrflags |= SDCARD_XFRDONE_FLAG;
                    if (priv->xfrflags == SDCARD_ALLDONE)
                      {
                        lpc17_40_endtransfer(priv, SDIOWAIT_TRANSFERDONE);
                      }
  
                    /* Otherwise, just disable futher transfer interrupts and
                     * wait for the DMA complete event.
                     */
  
                    else
                      {
                        lpc17_40_configxfrints(priv, 0);
                      }
                  }
                else
  #endif
                  {
                    /* Receive data from the RX FIFO */
  
                    lpc17_40_recvfifo(priv);
  
                    /* Then terminate the transfer */
  
                    lpc17_40_endtransfer(priv, SDIOWAIT_TRANSFERDONE);
                  }
              }
  
            /* Handle data block send/receive CRC failure */
  
            else if ((pending & SDCARD_STATUS_DCRCFAIL) != 0)
              {
                /* Terminate the transfer with an error */
  
                mcerr("ERROR: Data block CRC failure, remaining: %d\n", priv->remaining);
                lpc17_40_endtransfer(priv, SDIOWAIT_TRANSFERDONE | SDIOWAIT_ERROR);
              }
  
            /* Handle data timeout error */
  
            else if ((pending & SDCARD_STATUS_DTIMEOUT) != 0)
              {
                /* Terminate the transfer with an error */
  
                mcerr("ERROR: Data timeout, remaining: %d\n", priv->remaining);
                lpc17_40_endtransfer(priv, SDIOWAIT_TRANSFERDONE | SDIOWAIT_TIMEOUT);
              }
  
            /* Handle RX FIFO overrun error */
  
            else if ((pending & SDCARD_STATUS_RXOVERR) != 0)
              {
                /* Terminate the transfer with an error */
  
                mcerr("ERROR: RX FIFO overrun, remaining: %d\n", priv->remaining);
                lpc17_40_endtransfer(priv, SDIOWAIT_TRANSFERDONE | SDIOWAIT_ERROR);
              }
  
            /* Handle TX FIFO underrun error */
  
            else if ((pending & SDCARD_STATUS_TXUNDERR) != 0)
              {
                /* Terminate the transfer with an error */
  
                mcerr("ERROR: TX FIFO underrun, remaining: %d\n", priv->remaining);
                lpc17_40_endtransfer(priv, SDIOWAIT_TRANSFERDONE | SDIOWAIT_ERROR);
              }
  
            /* Handle start bit error */
  
            else if ((pending & SDCARD_STATUS_STBITERR) != 0)
              {
                /* Terminate the transfer with an error */
  
                mcerr("ERROR: Start bit, remaining: %d\n", priv->remaining);
                lpc17_40_endtransfer(priv, SDIOWAIT_TRANSFERDONE | SDIOWAIT_ERROR);
              }
          }
  
        /* Handle wait events *************************************************/
  
        pending  = enabled & priv->waitmask;
        if (pending != 0)
          {
            /* Is this a response completion event? */
  
            if ((pending & SDCARD_RESPDONE_STA) != 0)
              {
                /* Yes.. Is their a thread waiting for response done? */
  
                if ((priv->waitevents & SDIOWAIT_RESPONSEDONE) != 0)
                  {
                    /* Yes.. wake the thread up */
  
                    putreg32(SDCARD_RESPDONE_ICR | SDCARD_CMDDONE_ICR, LPC17_40_SDCARD_CLEAR);
                    lpc17_40_endwait(priv, SDIOWAIT_RESPONSEDONE);
                  }
              }
  
            /* Is this a command completion event? */
  
            if ((pending & SDCARD_CMDDONE_STA) != 0)
              {
                /* Yes.. Is their a thread waiting for command done? */
  
                if ((priv->waitevents & SDIOWAIT_RESPONSEDONE) != 0)
                  {
                    /* Yes.. wake the thread up */
  
                    putreg32(SDCARD_CMDDONE_ICR, LPC17_40_SDCARD_CLEAR);
                    lpc17_40_endwait(priv, SDIOWAIT_CMDDONE);
                  }
              }
          }
      }
  
    return OK;
  }
  
  /****************************************************************************
   * SD card Interface Methods
   ****************************************************************************/
  
  /****************************************************************************
   * Name: lpc17_40_lock
   *
   * Description:
   *   Locks the bus. Function calls low-level multiplexed bus routines to
   *   resolve bus requests and acknowledgment issues.
   *
   * Input Parameters:
   *   dev    - An instance of the SD card device interface
   *   lock   - TRUE to lock, FALSE to unlock.
   *
   * Returned Value:
   *   OK on success; a negated errno on failure
   *
   ****************************************************************************/
  
  #ifdef CONFIG_SDIO_MUXBUS
  static int lpc17_40_lock(FAR struct sdio_dev_s *dev, bool lock)
  {
    /* Single SD card instance so there is only one possibility.  The multiplex
     * bus is part of board support package.
     */
  
    lpc17_40_muxbus_sdio_lock(lock);
    return OK;
  }
  #endif
  
  /****************************************************************************
   * Name: lpc17_40_reset
   *
   * Description:
   *   Reset the SD card controller.  Undo all setup and initialization.
   *
   * Input Parameters:
   *   dev    - An instance of the SD card device interface
   *
   * Returned Value:
   *   None
   *
   ****************************************************************************/
  
  static void lpc17_40_reset(FAR struct sdio_dev_s *dev)
  {
    FAR struct lpc17_40_dev_s *priv = (FAR struct lpc17_40_dev_s *)dev;
    irqstate_t flags;
    uint32_t regval;
  
    /* Disable clocking */
  
    flags = enter_critical_section();
  
    /* Disable the SD Interface */
  
    regval = getreg32(LPC17_40_SDCARD_CLOCK);
    regval &= ~SDCARD_CLOCK_CLKEN;
    putreg32(regval, LPC17_40_SDCARD_CLOCK);
  
    lpc17_40_setpwrctrl(SDCARD_PWR_CTRL_OFF);
  
    /* Put SD card registers in their default, reset state */
  
    lpc17_40_default();
  
    /* Reset data */
  
    priv->waitevents = 0;      /* Set of events to be waited for */
    priv->waitmask   = 0;      /* Interrupt enables for event waiting */
    priv->wkupevent  = 0;      /* The event that caused the wakeup */
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
    priv->xfrflags   = 0;      /* Used to synchronize SD card and DMA completion events */
  #endif
  
    wd_cancel(priv->waitwdog); /* Cancel any timeouts */
  
    /* Interrupt mode data transfer support */
  
    priv->buffer     = 0;      /* Address of current R/W buffer */
    priv->remaining  = 0;      /* Number of bytes remaining in the transfer */
    priv->xfrmask    = 0;      /* Interrupt enables for data transfer */
  
    /* DMA data transfer support */
  
    priv->widebus    = false;  /* Required for DMA support */
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
    priv->dmamode    = false;  /* true: DMA mode transfer */
  #endif
  
    /* Configure and enable the SD card peripheral */
  
    lpc17_40_setclock(LPC17_40_CLCKCR_INIT | SDCARD_CLOCK_CLKEN);
    lpc17_40_setpwrctrl(SDCARD_PWR_CTRL_ON);
    leave_critical_section(flags);
  
    mcinfo("CLCKR: %08x POWER: %08x\n",
           getreg32(LPC17_40_SDCARD_CLOCK), getreg32(LPC17_40_SDCARD_PWR));
  }
  
  /****************************************************************************
   * Name: lpc17_40_capabilities
   *
   * Description:
   *   Get capabilities (and limitations) of the SDIO driver (optional)
   *
   * Input Parameters:
   *   dev   - Device-specific state data
   *
   * Returned Value:
   *   Returns a bitset of status values (see SDIO_CAPS_* defines)
   *
   ****************************************************************************/
  
  static sdio_capset_t lpc17_40_capabilities(FAR struct sdio_dev_s *dev)
  {
    sdio_capset_t caps = 0;
  
  #ifdef CONFIG_LPC17_40_SDCARD_WIDTH_D1_ONLY
    caps |= SDIO_CAPS_1BIT_ONLY;
  #endif
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
    caps |= SDIO_CAPS_DMASUPPORTED;
  #endif
  
    return caps;
  }
  
  /****************************************************************************
   * Name: lpc17_40_status
   *
   * Description:
   *   Get SD card status.
   *
   * Input Parameters:
   *   dev   - Device-specific state data
   *
   * Returned Value:
   *   Returns a bitset of status values (see lpc17_40_status_* defines)
   *
   ****************************************************************************/
  
  static sdio_statset_t lpc17_40_status(FAR struct sdio_dev_s *dev)
  {
    struct lpc17_40_dev_s *priv = (struct lpc17_40_dev_s *)dev;
    return priv->cdstatus;
  }
  
  /****************************************************************************
   * Name: lpc17_40_widebus
   *
   * Description:
   *   Called after change in Bus width has been selected (via ACMD6).  Most
   *   controllers will need to perform some special operations to work
   *   correctly in the new bus mode.
   *
   * Input Parameters:
   *   dev  - An instance of the SD card device interface
   *   wide - true: wide bus (4-bit) bus mode enabled
   *
   * Returned Value:
   *   None
   *
   ****************************************************************************/
  
  static void lpc17_40_widebus(FAR struct sdio_dev_s *dev, bool wide)
  {
    struct lpc17_40_dev_s *priv = (struct lpc17_40_dev_s *)dev;
    priv->widebus = wide;
  }
  
  /****************************************************************************
   * Name: lpc17_40_clock
   *
   * Description:
   *   Enable/disable SD card clocking
   *
   * Input Parameters:
   *   dev  - An instance of the SD card device interface
   *   rate - Specifies the clocking to use (see enum sdio_clock_e)
   *
   * Returned Value:
   *   None
   *
   ****************************************************************************/
  
  static void lpc17_40_clock(FAR struct sdio_dev_s *dev, enum sdio_clock_e rate)
  {
    uint32_t clkcr;
  
    switch (rate)
      {
        /* Disable clocking (with default ID mode divisor) */
  
        default:
        case CLOCK_SDIO_DISABLED:
          clkcr = LPC17_40_CLCKCR_INIT;
          return;
  
        /* Enable in initial ID mode clocking (<400KHz) */
  
        case CLOCK_IDMODE:
          clkcr = (LPC17_40_CLCKCR_INIT | SDCARD_CLOCK_CLKEN);
          break;
  
        /* Enable in MMC normal operation clocking */
  
        case CLOCK_MMC_TRANSFER:
          clkcr = (SDCARD_CLOCK_MMCXFR | SDCARD_CLOCK_CLKEN);
          lpc17_40_setpwrctrl(SDCARD_PWR_OPENDRAIN);
          break;
  
        /* SD normal operation clocking (wide 4-bit mode) */
  
        case CLOCK_SD_TRANSFER_4BIT:
  #ifndef CONFIG_LPC17_40_SDCARD_WIDTH_D1_ONLY
          clkcr = (SDCARD_CLOCK_SDWIDEXFR | SDCARD_CLOCK_CLKEN);
          break;
  #endif
  
        /* SD normal operation clocking (narrow 1-bit mode) */
  
        case CLOCK_SD_TRANSFER_1BIT:
          clkcr = (SDCARD_CLOCK_SDXFR | SDCARD_CLOCK_CLKEN);
          break;
      }
  
    /* Set the new clock frequency along with the clock enable/disable bit */
  
    lpc17_40_setclock(clkcr);
  }
  
  /****************************************************************************
   * Name: lpc17_40_attach
   *
   * Description:
   *   Attach and prepare interrupts
   *
   * Input Parameters:
   *   dev - An instance of the SD card device interface
   *
   * Returned Value:
   *   OK on success; A negated errno on failure.
   *
   ****************************************************************************/
  
  static int lpc17_40_attach(FAR struct sdio_dev_s *dev)
  {
    int ret;
  
    /* Attach the SD card interrupt handler */
  
    ret = irq_attach(LPC17_40_IRQ_MCI, lpc17_40_interrupt, NULL);
    if (ret == OK)
      {
  
        /* Disable all interrupts at the SD card controller and clear static
         * interrupt flags
         */
  
        putreg32(SDCARD_MASK0_RESET,       LPC17_40_SDCARD_MASK0);
        putreg32(SDCARD_CLEAR_STATICFLAGS, LPC17_40_SDCARD_CLEAR);
  
        /* Enable SD card interrupts at the NVIC.  They can now be enabled at
         * the SD card controller as needed.
         */
  
        up_enable_irq(LPC17_40_IRQ_MCI);
      }
  
    return ret;
  }
  
  /****************************************************************************
   * Name: lpc17_40_sendcmd
   *
   * Description:
   *   Send the SD card command
   *
   * Input Parameters:
   *   dev  - An instance of the SD card device interface
   *   cmd  - The command to send (32-bits, encoded)
   *   arg  - 32-bit argument required with some commands
   *
   * Returned Value:
   *   None
   *
   ****************************************************************************/
  
  static int lpc17_40_sendcmd(FAR struct sdio_dev_s *dev, uint32_t cmd, uint32_t arg)
  {
    uint32_t regval;
    uint32_t cmdidx;
  
    /* Set the SD card Argument value */
  
    putreg32(arg, LPC17_40_SDCARD_ARG);
  
    /* Clear CMDINDEX, WAITRESP, WAITINT, WAITPEND, and CPSMEN bits */
  
    regval = getreg32(LPC17_40_SDCARD_CMD);
    regval &= ~(SDCARD_CMD_INDEX_MASK | SDCARD_CMD_WAITRESP_MASK |
                SDCARD_CMD_WAITINT | SDCARD_CMD_WAITPEND |
                SDCARD_CMD_CPSMEN);
  
    /* Set WAITRESP bits */
  
    switch (cmd & MMCSD_RESPONSE_MASK)
      {
      case MMCSD_NO_RESPONSE:
        regval |= SDCARD_CMD_NORESPONSE;
        break;
  
      case MMCSD_R1_RESPONSE:
      case MMCSD_R1B_RESPONSE:
      case MMCSD_R3_RESPONSE:
      case MMCSD_R4_RESPONSE:
      case MMCSD_R5_RESPONSE:
      case MMCSD_R6_RESPONSE:
      case MMCSD_R7_RESPONSE:
        regval |= SDCARD_CMD_SHORTRESPONSE;
        break;
  
      case MMCSD_R2_RESPONSE:
        regval |= SDCARD_CMD_LONGRESPONSE;
        break;
      }
  
    /* Set CPSMEN and the command index */
  
    cmdidx  = (cmd & MMCSD_CMDIDX_MASK) >> MMCSD_CMDIDX_SHIFT;
    regval |= cmdidx | SDCARD_CMD_CPSMEN;
  
    mcinfo("cmd: %08x arg: %08x regval: %08x\n", cmd, arg, regval);
  
    /* Write the SD card CMD */
  
    putreg32(SDCARD_RESPDONE_ICR | SDCARD_CMDDONE_ICR, LPC17_40_SDCARD_CLEAR);
    putreg32(regval, LPC17_40_SDCARD_CMD);
    return OK;
  }
  
  /****************************************************************************
   * Name: lpc17_40_recvsetup
   *
   * Description:
   *   Setup hardware in preparation for data transfer from the card in non-DMA
   *   (interrupt driven mode).  This method will do whatever controller setup
   *   is necessary.  This would be called for SD memory just BEFORE sending
   *   CMD13 (SEND_STATUS), CMD17 (READ_SINGLE_BLOCK), CMD18
   *   (READ_MULTIPLE_BLOCKS), ACMD51 (SEND_SCR), etc.  Normally, SDCARD_WAITEVENT
   *   will be called to receive the indication that the transfer is complete.
   *
   * Input Parameters:
   *   dev    - An instance of the SD card device interface
   *   buffer - Address of the buffer in which to receive the data
   *   nbytes - The number of bytes in the transfer
   *
   * Returned Value:
   *   Number of bytes sent on success; a negated errno on failure
   *
   ****************************************************************************/
  
  static int lpc17_40_recvsetup(FAR struct sdio_dev_s *dev, FAR uint8_t *buffer,
                             size_t nbytes)
  {
    struct lpc17_40_dev_s *priv = (struct lpc17_40_dev_s *)dev;
    uint32_t dblocksize;
  
    DEBUGASSERT(priv != NULL && buffer != NULL && nbytes > 0);
    DEBUGASSERT(((uint32_t)buffer & 3) == 0);
  
    /* Reset the DPSM configuration */
  
    lpc17_40_datadisable();
    lpc17_40_sampleinit();
    lpc17_40_sample(priv, SAMPLENDX_BEFORE_SETUP);
  
    /* Save the destination buffer information for use by the interrupt handler */
  
    priv->buffer    = (uint32_t *)buffer;
    priv->remaining = nbytes;
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
    priv->dmamode   = false;
  #endif
  
    /* Then set up the SD card data path */
  
    dblocksize = lpc17_40_log2(nbytes) << SDCARD_DCTRL_DBLOCKSIZE_SHIFT;
    lpc17_40_dataconfig(SDCARD_DTIMER_DATATIMEOUT, nbytes,
                     dblocksize | SDCARD_DCTRL_DTDIR);
  
    /* And enable interrupts */
  
    lpc17_40_configxfrints(priv, SDCARD_RECV_MASK);
    lpc17_40_sample(priv, SAMPLENDX_AFTER_SETUP);
    return OK;
  }
  
  /****************************************************************************
   * Name: lpc17_40_sendsetup
   *
   * Description:
   *   Setup hardware in preparation for data transfer from the card.  This method
   *   will do whatever controller setup is necessary.  This would be called
   *   for SD memory just AFTER sending CMD24 (WRITE_BLOCK), CMD25
   *   (WRITE_MULTIPLE_BLOCK), ... and before SDCARD_SENDDATA is called.
   *
   * Input Parameters:
   *   dev    - An instance of the SD card device interface
   *   buffer - Address of the buffer containing the data to send
   *   nbytes - The number of bytes in the transfer
   *
   * Returned Value:
   *   Number of bytes sent on success; a negated errno on failure
   *
   ****************************************************************************/
  
  static int lpc17_40_sendsetup(FAR struct sdio_dev_s *dev, FAR const uint8_t *buffer,
                             size_t nbytes)
  {
    struct lpc17_40_dev_s *priv = (struct lpc17_40_dev_s *)dev;
    uint32_t dblocksize;
  
    DEBUGASSERT(priv != NULL && buffer != NULL && nbytes > 0);
    DEBUGASSERT(((uint32_t)buffer & 3) == 0);
  
    /* Reset the DPSM configuration */
  
    lpc17_40_datadisable();
    lpc17_40_sampleinit();
    lpc17_40_sample(priv, SAMPLENDX_BEFORE_SETUP);
  
    /* Save the source buffer information for use by the interrupt handler */
  
    priv->buffer    = (uint32_t *)buffer;
    priv->remaining = nbytes;
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
    priv->dmamode   = false;
  #endif
  
    /* Then set up the SD card data path */
  
    dblocksize = lpc17_40_log2(nbytes) << SDCARD_DCTRL_DBLOCKSIZE_SHIFT;
    lpc17_40_dataconfig(SDCARD_DTIMER_DATATIMEOUT, nbytes, dblocksize);
  
    /* Enable TX interrupts */
  
    lpc17_40_configxfrints(priv, SDCARD_SEND_MASK);
    lpc17_40_sample(priv, SAMPLENDX_AFTER_SETUP);
    return OK;
  }
  
  /****************************************************************************
   * Name: lpc17_40_cancel
   *
   * Description:
   *   Cancel the data transfer setup of SDCARD_RECVSETUP, SDCARD_SENDSETUP,
   *   SDCARD_DMARECVSETUP or SDCARD_DMASENDSETUP.  This must be called to cancel
   *   the data transfer setup if, for some reason, you cannot perform the
   *   transfer.
   *
   * Input Parameters:
   *   dev  - An instance of the SD card device interface
   *
   * Returned Value:
   *   OK is success; a negated errno on failure
   *
   ****************************************************************************/
  
  static int lpc17_40_cancel(FAR struct sdio_dev_s *dev)
  {
    struct lpc17_40_dev_s *priv = (struct lpc17_40_dev_s *)dev;
  
    /* Disable all transfer- and event- related interrupts */
  
    lpc17_40_configxfrints(priv, 0);
    lpc17_40_configwaitints(priv, 0, 0, 0);
  
    /* Clearing pending interrupt status on all transfer- and event- related
     * interrupts
     */
  
    putreg32(SDCARD_WAITALL_ICR, LPC17_40_SDCARD_CLEAR);
  
    /* Cancel any watchdog timeout */
  
    (void)wd_cancel(priv->waitwdog);
  
    /* If this was a DMA transfer, make sure that DMA is stopped */
  
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
    if (priv->dmamode)
      {
        /* Make sure that the DMA is stopped (it will be stopped automatically
         * on normal transfers, but not necessarily when the transfer terminates
         * on an error condition.
         */
  
        lpc17_40_dmastop(priv->dma);
      }
  #endif
  
    /* Mark no transfer in progress */
  
    priv->remaining = 0;
    return OK;
  }
  
  /****************************************************************************
   * Name: lpc17_40_waitresponse
   *
   * Description:
   *   Poll-wait for the response to the last command to be ready.
   *
   * Input Parameters:
   *   dev  - An instance of the SD card device interface
   *   cmd  - The command that was sent.  See 32-bit command definitions above.
   *
   * Returned Value:
   *   OK is success; a negated errno on failure
   *
   ****************************************************************************/
  
  static int lpc17_40_waitresponse(FAR struct sdio_dev_s *dev, uint32_t cmd)
  {
    int32_t timeout;
    uint32_t events;
  
    switch (cmd & MMCSD_RESPONSE_MASK)
      {
      case MMCSD_NO_RESPONSE:
        events  = SDCARD_CMDDONE_STA;
        timeout = SDCARD_CMDTIMEOUT;
        break;
  
      case MMCSD_R1_RESPONSE:
      case MMCSD_R1B_RESPONSE:
      case MMCSD_R2_RESPONSE:
      case MMCSD_R6_RESPONSE:
        events  = SDCARD_RESPDONE_STA;
        timeout = SDCARD_LONGTIMEOUT;
        break;
  
      case MMCSD_R4_RESPONSE:
      case MMCSD_R5_RESPONSE:
        return -ENOSYS;
  
      case MMCSD_R3_RESPONSE:
      case MMCSD_R7_RESPONSE:
        events  = SDCARD_RESPDONE_STA;
        timeout = SDCARD_CMDTIMEOUT;
        break;
  
      default:
        return -EINVAL;
      }
  
    /* Then wait for the response (or timeout) */
  
    while ((getreg32(LPC17_40_SDCARD_STATUS) & events) == 0)
      {
        if (--timeout <= 0)
          {
            mcerr("ERROR: Timeout cmd: %08x events: %08x STA: %08x\n",
                 cmd, events, getreg32(LPC17_40_SDCARD_STATUS));
  
            return -ETIMEDOUT;
          }
      }
  
    putreg32(SDCARD_CMDDONE_ICR, LPC17_40_SDCARD_CLEAR);
    return OK;
  }
  
  /****************************************************************************
   * Name: lpc17_40_recvRx
   *
   * Description:
   *   Receive response to SD card command.  Only the critical payload is
   *   returned -- that is 32 bits for 48 bit status and 128 bits for 136 bit
   *   status.  The driver implementation should verify the correctness of
   *   the remaining, non-returned bits (CRCs, CMD index, etc.).
   *
   * Input Parameters:
   *   dev    - An instance of the SD card device interface
   *   Rx - Buffer in which to receive the response
   *
   * Returned Value:
   *   Number of bytes sent on success; a negated errno on failure.  Here a
   *   failure means only a faiure to obtain the requested reponse (due to
   *   transport problem -- timeout, CRC, etc.).  The implementation only
   *   assures that the response is returned intacta and does not check errors
   *   within the response itself.
   *
   ****************************************************************************/
  
  static int lpc17_40_recvshortcrc(FAR struct sdio_dev_s *dev, uint32_t cmd, uint32_t *rshort)
  {
  #ifdef CONFIG_DEBUG_FEATURES
    uint32_t respcmd;
  #endif
    uint32_t regval;
    int ret = OK;
  
    /* R1  Command response (48-bit)
     *     47        0               Start bit
     *     46        0               Transmission bit (0=from card)
     *     45:40     bit5   - bit0   Command index (0-63)
     *     39:8      bit31  - bit0   32-bit card status
     *     7:1       bit6   - bit0   CRC7
     *     0         1               End bit
     *
     * R1b Identical to R1 with the additional busy signaling via the data
     *     line.
     *
     * R6  Published RCA Response (48-bit, SD card only)
     *     47        0               Start bit
     *     46        0               Transmission bit (0=from card)
     *     45:40     bit5   - bit0   Command index (0-63)
     *     39:8      bit31  - bit0   32-bit Argument Field, consisting of:
     *                               [31:16] New published RCA of card
     *                               [15:0]  Card status bits {23,22,19,12:0}
     *     7:1       bit6   - bit0   CRC7
     *     0         1               End bit
     */
  
  
  #ifdef CONFIG_DEBUG_FEATURES
    if (!rshort)
      {
        mcerr("ERROR: rshort=NULL\n");
        ret = -EINVAL;
      }
  
    /* Check that this is the correct response to this command */
  
    else if ((cmd & MMCSD_RESPONSE_MASK) != MMCSD_R1_RESPONSE &&
             (cmd & MMCSD_RESPONSE_MASK) != MMCSD_R1B_RESPONSE &&
             (cmd & MMCSD_RESPONSE_MASK) != MMCSD_R6_RESPONSE)
      {
        mcerr("ERROR: Wrong response CMD=%08x\n", cmd);
        ret = -EINVAL;
      }
    else
  #endif
      {
        /* Check if a timeout or CRC error occurred */
  
        regval = getreg32(LPC17_40_SDCARD_STATUS);
        if ((regval & SDCARD_STATUS_CTIMEOUT) != 0)
          {
            mcerr("ERROR: Command timeout: %08x\n", regval);
            ret = -ETIMEDOUT;
          }
        else if ((regval & SDCARD_STATUS_CCRCFAIL) != 0)
          {
            mcerr("ERROR: CRC failure: %08x\n", regval);
            ret = -EIO;
          }
  #ifdef CONFIG_DEBUG_FEATURES
        else
          {
            /* Check response received is of desired command */
  
            respcmd = getreg32(LPC17_40_SDCARD_RESPCMD);
            if ((uint8_t)(respcmd & SDCARD_RESPCMD_MASK) != (cmd & MMCSD_CMDIDX_MASK))
              {
                mcerr("ERROR: RESCMD=%02x CMD=%08x\n", respcmd, cmd);
                ret = -EINVAL;
              }
          }
  #endif
      }
  
    /* Clear all pending message completion events and return the R1/R6 response */
  
    putreg32(SDCARD_RESPDONE_ICR | SDCARD_CMDDONE_ICR, LPC17_40_SDCARD_CLEAR);
    *rshort = getreg32(LPC17_40_SDCARD_RESP0);
    return ret;
  }
  
  static int lpc17_40_recvlong(FAR struct sdio_dev_s *dev, uint32_t cmd, uint32_t rlong[4])
  {
    uint32_t regval;
    int ret = OK;
  
    /* R2  CID, CSD register (136-bit)
     *     135       0               Start bit
     *     134       0               Transmission bit (0=from card)
     *     133:128   bit5   - bit0   Reserved
     *     127:1     bit127 - bit1   127-bit CID or CSD register
     *                               (including internal CRC)
     *     0         1               End bit
     */
  
  #ifdef CONFIG_DEBUG_FEATURES
    /* Check that R1 is the correct response to this command */
  
    if ((cmd & MMCSD_RESPONSE_MASK) != MMCSD_R2_RESPONSE)
      {
        mcerr("ERROR: Wrong response CMD=%08x\n", cmd);
        ret = -EINVAL;
      }
    else
  #endif
      {
        /* Check if a timeout or CRC error occurred */
  
        regval = getreg32(LPC17_40_SDCARD_STATUS);
        if (regval & SDCARD_STATUS_CTIMEOUT)
          {
            mcerr("ERROR: Timeout STA: %08x\n", regval);
            ret = -ETIMEDOUT;
          }
        else if (regval & SDCARD_STATUS_CCRCFAIL)
          {
            mcerr("ERROR: CRC fail STA: %08x\n", regval);
            ret = -EIO;
          }
      }
  
    /* Return the long response */
  
    putreg32(SDCARD_RESPDONE_ICR | SDCARD_CMDDONE_ICR, LPC17_40_SDCARD_CLEAR);
    if (rlong)
      {
        rlong[0] = getreg32(LPC17_40_SDCARD_RESP0);
        rlong[1] = getreg32(LPC17_40_SDCARD_RESP1);
        rlong[2] = getreg32(LPC17_40_SDCARD_RESP2);
        rlong[3] = getreg32(LPC17_40_SDCARD_RESP3);
      }
  
    return ret;
  }
  
  static int lpc17_40_recvshort(FAR struct sdio_dev_s *dev, uint32_t cmd, uint32_t *rshort)
  {
    uint32_t regval;
    int ret = OK;
  
    /* R3  OCR (48-bit)
     *     47        0               Start bit
     *     46        0               Transmission bit (0=from card)
     *     45:40     bit5   - bit0   Reserved
     *     39:8      bit31  - bit0   32-bit OCR register
     *     7:1       bit6   - bit0   Reserved
     *     0         1               End bit
     */
  
    /* Check that this is the correct response to this command */
  
  #ifdef CONFIG_DEBUG_FEATURES
    if ((cmd & MMCSD_RESPONSE_MASK) != MMCSD_R3_RESPONSE &&
        (cmd & MMCSD_RESPONSE_MASK) != MMCSD_R7_RESPONSE)
      {
        mcerr("ERROR: Wrong response CMD=%08x\n", cmd);
        ret = -EINVAL;
      }
    else
  #endif
      {
        /* Check if a timeout occurred (Apparently a CRC error can terminate
         * a good response)
         */
  
        regval = getreg32(LPC17_40_SDCARD_STATUS);
        if (regval & SDCARD_STATUS_CTIMEOUT)
          {
            mcerr("ERROR: Timeout STA: %08x\n", regval);
            ret = -ETIMEDOUT;
          }
      }
  
    putreg32(SDCARD_RESPDONE_ICR | SDCARD_CMDDONE_ICR, LPC17_40_SDCARD_CLEAR);
    if (rshort)
      {
        *rshort = getreg32(LPC17_40_SDCARD_RESP0);
      }
    return ret;
  }
  
  /* MMC responses not supported */
  
  static int lpc17_40_recvnotimpl(FAR struct sdio_dev_s *dev, uint32_t cmd, uint32_t *rnotimpl)
  {
    putreg32(SDCARD_RESPDONE_ICR | SDCARD_CMDDONE_ICR, LPC17_40_SDCARD_CLEAR);
    return -ENOSYS;
  }
  
  /****************************************************************************
   * Name: lpc17_40_waitenable
   *
   * Description:
   *   Enable/disable of a set of SD card wait events.  This is part of the
   *   the SDCARD_WAITEVENT sequence.  The set of to-be-waited-for events is
   *   configured before calling lpc17_40_eventwait.  This is done in this way
   *   to help the driver to eliminate race conditions between the command
   *   setup and the subsequent events.
   *
   *   The enabled events persist until either (1) SDCARD_WAITENABLE is called
   *   again specifying a different set of wait events, or (2) SDCARD_EVENTWAIT
   *   returns.
   *
   * Input Parameters:
   *   dev      - An instance of the SD card device interface
   *   eventset - A bitset of events to enable or disable (see SDIOWAIT_*
   *              definitions). 0=disable; 1=enable.
   *
   * Returned Value:
   *   None
   *
   ****************************************************************************/
  
  static void lpc17_40_waitenable(FAR struct sdio_dev_s *dev,
                               sdio_eventset_t eventset)
  {
    struct lpc17_40_dev_s *priv = (struct lpc17_40_dev_s *)dev;
    uint32_t waitmask;
  
    DEBUGASSERT(priv != NULL);
  
    /* Disable event-related interrupts */
  
    lpc17_40_configwaitints(priv, 0, 0, 0);
  
    /* Select the interrupt mask that will give us the appropriate wakeup
     * interrupts.
     */
  
    waitmask = 0;
    if ((eventset & SDIOWAIT_CMDDONE) != 0)
      {
        waitmask |= SDCARD_CMDDONE_MASK;
      }
  
    if ((eventset & SDIOWAIT_RESPONSEDONE) != 0)
      {
        waitmask |= SDCARD_RESPDONE_MASK;
      }
  
    if ((eventset & SDIOWAIT_TRANSFERDONE) != 0)
      {
        waitmask |= SDCARD_XFRDONE_MASK;
      }
  
    /* Enable event-related interrupts */
  
    putreg32(SDCARD_WAITALL_ICR, LPC17_40_SDCARD_CLEAR);
    lpc17_40_configwaitints(priv, waitmask, eventset, 0);
  }
  
  /****************************************************************************
   * Name: lpc17_40_eventwait
   *
   * Description:
   *   Wait for one of the enabled events to occur (or a timeout).  Note that
   *   all events enabled by SDCARD_WAITEVENTS are disabled when lpc17_40_eventwait
   *   returns.  SDCARD_WAITEVENTS must be called again before lpc17_40_eventwait
   *   can be used again.
   *
   * Input Parameters:
   *   dev     - An instance of the SD card device interface
   *   timeout - Maximum time in milliseconds to wait.  Zero means immediate
   *             timeout with no wait.  The timeout value is ignored if
   *             SDIOWAIT_TIMEOUT is not included in the waited-for eventset.
   *
   * Returned Value:
   *   Event set containing the event(s) that ended the wait.  Should always
   *   be non-zero.  All events are disabled after the wait concludes.
   *
   ****************************************************************************/
  
  static sdio_eventset_t lpc17_40_eventwait(FAR struct sdio_dev_s *dev,
                                         uint32_t timeout)
  {
    struct lpc17_40_dev_s *priv = (struct lpc17_40_dev_s *)dev;
    sdio_eventset_t wkupevent = 0;
    irqstate_t flags;
    int ret;
  
    /* There is a race condition here... the event may have completed before
     * we get here.  In this case waitevents will be zero, but wkupevents will
     * be non-zero (and, hopefully, the semaphore count will also be non-zero.
     */
  
    flags = enter_critical_section();
    DEBUGASSERT(priv->waitevents != 0 || priv->wkupevent != 0);
  
    /* Check if the timeout event is specified in the event set */
  
    if ((priv->waitevents & SDIOWAIT_TIMEOUT) != 0)
      {
        int delay;
  
        /* Yes.. Handle a cornercase: The user request a timeout event but
         * with timeout == 0?
         */
  
        if (!timeout)
          {
            /* Then just tell the caller that we already timed out */
  
            wkupevent = SDIOWAIT_TIMEOUT;
            goto errout;
          }
  
        /* Start the watchdog timer */
  
        delay = MSEC2TICK(timeout);
        ret   = wd_start(priv->waitwdog, delay, (wdentry_t)lpc17_40_eventtimeout,
                         1, (uint32_t)priv);
        if (ret < 0)
          {
            mcerr("ERROR: wd_start failed: %d\n", ret);
          }
      }
  
    /* Loop until the event (or the timeout occurs). Race conditions are avoided
     * by calling lpc17_40_waitenable prior to triggering the logic that will cause
     * the wait to terminate.  Under certain race conditions, the waited-for
     * may have already occurred before this function was called!
     */
  
    for (; ; )
      {
        /* Wait for an event in event set to occur.  If this the event has already
         * occurred, then the semaphore will already have been incremented and
         * there will be no wait.
         */
  
        lpc17_40_takesem(priv);
        wkupevent = priv->wkupevent;
  
        /* Check if the event has occurred.  When the event has occurred, then
         * evenset will be set to 0 and wkupevent will be set to a nonzero value.
         */
  
        if (wkupevent != 0)
          {
            /* Yes... break out of the loop with wkupevent non-zero */
  
            break;
          }
      }
  
    /* Disable event-related interrupts */
  
    lpc17_40_configwaitints(priv, 0, 0, 0);
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
    priv->xfrflags   = 0;
  #endif
  
  errout:
    leave_critical_section(flags);
    lpc17_40_dumpsamples(priv);
    return wkupevent;
  }
  
  /****************************************************************************
   * Name: lpc17_40_callbackenable
   *
   * Description:
   *   Enable/disable of a set of SD card callback events.  This is part of the
   *   the SD card callback sequence.  The set of events is configured to enabled
   *   callbacks to the function provided in lpc17_40_registercallback.
   *
   *   Events are automatically disabled once the callback is performed and no
   *   further callback events will occur until they are again enabled by
   *   calling this methos.
   *
   * Input Parameters:
   *   dev      - An instance of the SD card device interface
   *   eventset - A bitset of events to enable or disable (see SDIOMEDIA_*
   *              definitions). 0=disable; 1=enable.
   *
   * Returned Value:
   *   None
   *
   ****************************************************************************/
  
  static void lpc17_40_callbackenable(FAR struct sdio_dev_s *dev,
                                   sdio_eventset_t eventset)
  {
    struct lpc17_40_dev_s *priv = (struct lpc17_40_dev_s *)dev;
  
    mcinfo("eventset: %02x\n", eventset);
    DEBUGASSERT(priv != NULL);
  
    priv->cbevents = eventset;
    lpc17_40_callback(priv);
  }
  
  /****************************************************************************
   * Name: lpc17_40_registercallback
   *
   * Description:
   *   Register a callback that that will be invoked on any media status
   *   change.  Callbacks should not be made from interrupt handlers, rather
   *   interrupt level events should be handled by calling back on the work
   *   thread.
   *
   *   When this method is called, all callbacks should be disabled until they
   *   are enabled via a call to SDCARD_CALLBACKENABLE
   *
   * Input Parameters:
   *   dev -      Device-specific state data
   *   callback - The funtion to call on the media change
   *   arg -      A caller provided value to return with the callback
   *
   * Returned Value:
   *   0 on success; negated errno on failure.
   *
   ****************************************************************************/
  
  static int lpc17_40_registercallback(FAR struct sdio_dev_s *dev,
                                    worker_t callback, void *arg)
  {
    struct lpc17_40_dev_s *priv = (struct lpc17_40_dev_s *)dev;
  
    /* Disable callbacks and register this callback and is argument */
  
    mcinfo("Register %p(%p)\n", callback, arg);
    DEBUGASSERT(priv != NULL);
  
    priv->cbevents = 0;
    priv->cbarg    = arg;
    priv->callback = callback;
    return OK;
  }
  
  /****************************************************************************
   * Name: lpc17_40_dmarecvsetup
   *
   * Description:
   *   Setup to perform a read DMA.  If the processor supports a data cache,
   *   then this method will also make sure that the contents of the DMA memory
   *   and the data cache are coherent.  For read transfers this may mean
   *   invalidating the data cache.
   *
   * Input Parameters:
   *   dev    - An instance of the SD card device interface
   *   buffer - The memory to DMA from
   *   buflen - The size of the DMA transfer in bytes
   *
   * Returned Value:
   *   OK on success; a negated errno on failure
   *
   ****************************************************************************/
  
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
  static int lpc17_40_dmarecvsetup(FAR struct sdio_dev_s *dev, FAR uint8_t *buffer,
                                size_t buflen)
  {
    struct lpc17_40_dev_s *priv = (struct lpc17_40_dev_s *)dev;
    uint32_t dblocksize;
    uint32_t regval;
    int ret = -EINVAL;
  
    DEBUGASSERT(priv != NULL && buffer != NULL && buflen > 0);
    DEBUGASSERT(((uint32_t)buffer & 3) == 0);
  
    /* Reset the DPSM configuration */
  
    lpc17_40_datadisable();
  
    /* Wide bus operation is required for DMA */
  
    if (priv->widebus)
      {
        lpc17_40_sampleinit();
        lpc17_40_sample(priv, SAMPLENDX_BEFORE_SETUP);
  
        /* Save the destination buffer information for use by the interrupt handler */
  
        priv->buffer    = (uint32_t *)buffer;
        priv->remaining = buflen;
        priv->dmamode   = true;
  
        /* Then set up the SD card data path */
  
        dblocksize = lpc17_40_log2(buflen) << SDCARD_DCTRL_DBLOCKSIZE_SHIFT;
        lpc17_40_dataconfig(SDCARD_DTIMER_DATATIMEOUT, buflen,
                         dblocksize | SDCARD_DCTRL_DTDIR);
  
        /* Configure the RX DMA */
  
        lpc17_40_configxfrints(priv, SDCARD_DMARECV_MASK);
  
        regval  = getreg32(LPC17_40_SDCARD_DCTRL);
        regval |= SDCARD_DCTRL_DMAEN;
        putreg32(regval, LPC17_40_SDCARD_DCTRL);
  
        ret = lpc17_40_dmasetup(priv->dma, SDCARD_RXDMA32_CONTROL,
                             SDCARD_RXDMA32_CONFIG, LPC17_40_SDCARD_FIFO,
                             (uint32_t)buffer, (buflen + 3) >> 2);
        if (ret == OK)
          {
            /* Start the DMA */
  
            lpc17_40_sample(priv, SAMPLENDX_BEFORE_ENABLE);
            lpc17_40_dmastart(priv->dma, lpc17_40_dmacallback, priv);
            lpc17_40_sample(priv, SAMPLENDX_AFTER_SETUP);
          }
      }
  
    return ret;
  }
  #endif
  
  /****************************************************************************
   * Name: lpc17_40_dmasendsetup
   *
   * Description:
   *   Setup to perform a write DMA.  If the processor supports a data cache,
   *   then this method will also make sure that the contents of the DMA memory
   *   and the data cache are coherent.  For write transfers, this may mean
   *   flushing the data cache.
   *
   * Input Parameters:
   *   dev    - An instance of the SD card device interface
   *   buffer - The memory to DMA into
   *   buflen - The size of the DMA transfer in bytes
   *
   * Returned Value:
   *   OK on success; a negated errno on failure
   *
   ****************************************************************************/
  
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
  static int lpc17_40_dmasendsetup(FAR struct sdio_dev_s *dev,
                                FAR const uint8_t *buffer, size_t buflen)
  {
    struct lpc17_40_dev_s *priv = (struct lpc17_40_dev_s *)dev;
    uint32_t dblocksize;
    uint32_t regval;
    int ret = -EINVAL;
  
    DEBUGASSERT(priv != NULL && buffer != NULL && buflen > 0);
    DEBUGASSERT(((uint32_t)buffer & 3) == 0);
  
    /* Reset the DPSM configuration */
  
    lpc17_40_datadisable();
  
    /* Wide bus operation is required for DMA */
  
    if (priv->widebus)
      {
        lpc17_40_sampleinit();
        lpc17_40_sample(priv, SAMPLENDX_BEFORE_SETUP);
  
        /* Save the source buffer information for use by the interrupt handler */
  
        priv->buffer    = (uint32_t *)buffer;
        priv->remaining = buflen;
        priv->dmamode   = true;
  
        /* Then set up the SD card data path */
  
        dblocksize = lpc17_40_log2(buflen) << SDCARD_DCTRL_DBLOCKSIZE_SHIFT;
        lpc17_40_dataconfig(SDCARD_DTIMER_DATATIMEOUT, buflen, dblocksize);
  
        /* Configure the TX DMA */
  
        ret = lpc17_40_dmasetup(priv->dma, SDCARD_TXDMA32_CONTROL,
                             SDCARD_TXDMA32_CONFIG, (uint32_t)buffer,
                             LPC17_40_SDCARD_FIFO, (buflen + 3) >> 2);
        if (ret == OK)
          {
            lpc17_40_sample(priv, SAMPLENDX_BEFORE_ENABLE);
  
            regval  = getreg32(LPC17_40_SDCARD_DCTRL);
            regval |= SDCARD_DCTRL_DMAEN;
            putreg32(regval, LPC17_40_SDCARD_DCTRL);
  
            /* Start the DMA */
  
            lpc17_40_dmastart(priv->dma, lpc17_40_dmacallback, priv);
            lpc17_40_sample(priv, SAMPLENDX_AFTER_SETUP);
  
            /* Enable TX interrupts */
  
            lpc17_40_configxfrints(priv, SDCARD_DMASEND_MASK);
          }
      }
  
    return ret;
  }
  #endif
  
  /****************************************************************************
   * Initialization/uninitialization/reset
   ****************************************************************************/
  /****************************************************************************
   * Name: lpc17_40_callback
   *
   * Description:
   *   Perform callback.
   *
   * Assumptions:
   *   This function does not execute in the context of an interrupt handler.
   *   It may be invoked on any user thread or scheduled on the work thread
   *   from an interrupt handler.
   *
   ****************************************************************************/
  
  static void lpc17_40_callback(void *arg)
  {
    struct lpc17_40_dev_s *priv = (struct lpc17_40_dev_s *)arg;
  
    /* Is a callback registered? */
  
    DEBUGASSERT(priv != NULL);
    mcinfo("Callback %p(%p) cbevents: %02x cdstatus: %02x\n",
           priv->callback, priv->cbarg, priv->cbevents, priv->cdstatus);
  
    if (priv->callback)
      {
        /* Yes.. Check for enabled callback events */
  
        if ((priv->cdstatus & SDIO_STATUS_PRESENT) != 0)
          {
            /* Media is present.  Is the media inserted event enabled? */
  
            if ((priv->cbevents & SDIOMEDIA_INSERTED) == 0)
              {
                /* No... return without performing the callback */
  
                return;
              }
          }
        else
          {
            /* Media is not present.  Is the media eject event enabled? */
  
            if ((priv->cbevents & SDIOMEDIA_EJECTED) == 0)
              {
                /* No... return without performing the callback */
  
                return;
              }
          }
  
        /* Perform the callback, disabling further callbacks.  Of course, the
         * the callback can (and probably should) re-enable callbacks.
         */
  
        priv->cbevents = 0;
  
        /* Callbacks cannot be performed in the context of an interrupt handler.
         * If we are in an interrupt handler, then queue the callback to be
         * performed later on the work thread.
         */
  
        if (up_interrupt_context())
          {
            /* Yes.. queue it */
  
             mcinfo("Queuing callback to %p(%p)\n", priv->callback, priv->cbarg);
            (void)work_queue(HPWORK, &priv->cbwork, (worker_t)priv->callback, priv->cbarg, 0);
          }
        else
          {
            /* No.. then just call the callback here */
  
            mcinfo("Callback to %p(%p)\n", priv->callback, priv->cbarg);
            priv->callback(priv->cbarg);
          }
      }
  }
  
  /****************************************************************************
   * Name: lpc17_40_default
   *
   * Description:
   *   Restore SD card registers to their default, reset values
   *
   ****************************************************************************/
  
  static void lpc17_40_default(void)
  {
    putreg32(SDCARD_PWR_RESET,    LPC17_40_SDCARD_PWR);
    putreg32(SDCARD_CLOCK_RESET,  LPC17_40_SDCARD_CLOCK);
    putreg32(SDCARD_ARG_RESET,    LPC17_40_SDCARD_ARG);
    putreg32(SDCARD_CMD_RESET,    LPC17_40_SDCARD_CMD);
    putreg32(SDCARD_DTIMER_RESET, LPC17_40_SDCARD_DTIMER);
    putreg32(SDCARD_DLEN_RESET,   LPC17_40_SDCARD_DLEN);
    putreg32(SDCARD_DCTRL_RESET,  LPC17_40_SDCARD_DCTRL);
    putreg32(SDCARD_CLEAR_RESET,  LPC17_40_SDCARD_CLEAR);
    putreg32(SDCARD_MASK0_RESET,  LPC17_40_SDCARD_MASK0);
  }
  
  /****************************************************************************
   * Public Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Name: sdio_initialize
   *
   * Description:
   *   Initialize SD card for operation.
   *
   * Input Parameters:
   *   slotno - Not used.
   *
   * Returned Value:
   *   A reference to an SD card interface structure.  NULL is returned on failures.
   *
   ****************************************************************************/
  
  FAR struct sdio_dev_s *sdio_initialize(int slotno)
  {
    uint32_t   regval;
  
    /* There is only one slot */
  
    struct lpc17_40_dev_s *priv = &g_scard_dev;
  
    /* Enable power on SD Interface */
  
    regval  = getreg32(LPC17_40_SYSCON_PCONP);
    regval |= SYSCON_PCONP_PCSDC;
    putreg32(regval, LPC17_40_SYSCON_PCONP);
  
    /* Initialize the SD card slot structure */
    /* Initialize semaphores */
  
    nxsem_init(&priv->waitsem, 0, 0);
  
    /* The waitsem semaphore is used for signaling and, hence, should not have
     * priority inheritance enabled.
     */
  
    nxsem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
  
    /* Create a watchdog timer */
  
    priv->waitwdog = wd_create();
    DEBUGASSERT(priv->waitwdog);
  
  #ifdef CONFIG_LPC17_40_SDCARD_DMA
    /* Configure the SDCARD DMA request */
  
    lpc17_40_dmaconfigure(DMA_REQ_SDCARD, DMA_DMASEL_SDCARD);
  
    /* Allocate a DMA channel for SDCARD DMA */
  
    priv->dma = lpc17_40_dmachannel();
    DEBUGASSERT(priv->dma);
  #endif
  
    /* Configure GPIOs for 4-bit, wide-bus operation.
     *
     * If bus is multiplexed then there is a custom bus configuration utility
     * in the scope of the board support package.
     */
  
  #ifndef CONFIG_SDIO_MUXBUS
    lpc17_40_configgpio(GPIO_SD_DAT0);
  #ifndef CONFIG_LPC17_40_SDCARD_WIDTH_D1_ONLY
    lpc17_40_configgpio(GPIO_SD_DAT1);
    lpc17_40_configgpio(GPIO_SD_DAT2);
    lpc17_40_configgpio(GPIO_SD_DAT3);
  #endif
    lpc17_40_configgpio(GPIO_SD_CLK);
    lpc17_40_configgpio(GPIO_SD_CMD);
  #endif
  
    /* Reset the card and assure that it is in the initial, unconfigured
     * state.
     */
  
    lpc17_40_reset(&priv->dev);
  
    return &g_scard_dev.dev;
  }
  
  /****************************************************************************
   * Name: sdio_mediachange
   *
   * Description:
   *   Called by board-specific logic -- possibly from an interrupt handler --
   *   in order to signal to the driver that a card has been inserted or
   *   removed from the slot.
   *
   * Input Parameters:
   *   dev        - An instance of the SD card driver device state structure.
   *   cardinslot - true is a card has been detected in the slot; false if a
   *                card has been removed from the slot.  Only transitions
   *                (inserted->removed or removed->inserted should be reported)
   *
   * Returned Value:
   *   None
   *
   ****************************************************************************/
  
  void sdio_mediachange(FAR struct sdio_dev_s *dev, bool cardinslot)
  {
    struct lpc17_40_dev_s *priv = (struct lpc17_40_dev_s *)dev;
    sdio_statset_t cdstatus;
    irqstate_t flags;
  
    /* Update card status */
  
    flags = enter_critical_section();
    cdstatus = priv->cdstatus;
    if (cardinslot)
      {
        priv->cdstatus |= SDIO_STATUS_PRESENT;
      }
    else
      {
        priv->cdstatus &= ~SDIO_STATUS_PRESENT;
      }
    mcinfo("cdstatus OLD: %02x NEW: %02x\n", cdstatus, priv->cdstatus);
  
    /* Perform any requested callback if the status has changed */
  
    if (cdstatus != priv->cdstatus)
      {
        lpc17_40_callback(priv);
      }
  
    leave_critical_section(flags);
  }
  
  /****************************************************************************
   * Name: sdio_wrprotect
   *
   * Description:
   *   Called by board-specific logic to report if the card in the slot is
   *   mechanically write protected.
   *
   * Input Parameters:
   *   dev       - An instance of the SD card driver device state structure.
   *   wrprotect - true is a card is writeprotected.
   *
   * Returned Value:
   *   None
   *
   ****************************************************************************/
  
  void sdio_wrprotect(FAR struct sdio_dev_s *dev, bool wrprotect)
  {
    struct lpc17_40_dev_s *priv = (struct lpc17_40_dev_s *)dev;
    irqstate_t flags;
  
    /* Update card status */
  
    flags = enter_critical_section();
    if (wrprotect)
      {
        priv->cdstatus |= SDIO_STATUS_WRPROTECTED;
      }
    else
      {
        priv->cdstatus &= ~SDIO_STATUS_WRPROTECTED;
      }
  
    mcinfo("cdstatus: %02x\n", priv->cdstatus);
    leave_critical_section(flags);
  }
  #endif /* CONFIG_LPC17_40_SDCARD */
  