text: /************************************************************************************
   * configs/freedom-kl25z/src/kl_adxl345.c
   *
   *   Copyright (C) 2014 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 <stdbool.h>
  #include <stdio.h>
  #include <debug.h>
  #include <errno.h>
  
  #include <nuttx/spi/spi.h>
  #include <nuttx/sensors/adxl345.h>
  
  #include <nuttx/irq.h>
  
  #include "freedom-kl25z.h"
  #include "kl_gpio.h"
  
  /****************************************************************************
   * Pre-processor Definitions
   ****************************************************************************/
  /* Configuration ************************************************************/
  
  #ifdef CONFIG_SENSORS_ADXL345
  #ifndef CONFIG_KL_SPI0
  #  error "ADXL345 support requires CONFIG_KL_SPI0"
  #endif
  
  #ifndef CONFIG_ADXL345_SPI
  #  error "Only the ADXL345 SPI interface is supported"
  #endif
  
  #ifdef CONFIG_ADXL345_I2C
  #  error "Only the ADXL345 SPI interface is supported"
  #endif
  
  #ifndef CONFIG_ADXL345_FREQUENCY
  #  define CONFIG_ADXL345_FREQUENCY 500000
  #endif
  
  #ifndef CONFIG_ADXL345_SPIDEV
  #  define CONFIG_ADXL345_SPIDEV 0
  #endif
  
  #if CONFIG_ADXL345_SPIDEV != 0
  #  error "CONFIG_ADXL345_SPIDEV must be zero"
  #endif
  
  #ifndef CONFIG_ADXL345_DEVMINOR
  #  define CONFIG_ADXL345_DEVMINOR 0
  #endif
  
  /****************************************************************************
   * Private Types
   ****************************************************************************/
  
  struct kl_adxl345config_s
  {
    /* Configuration structure as seen by the ADXL345 driver */
  
    struct adxl345_config_s config;
  
    /* Additional private definitions only known to this driver */
  
    ADXL345_HANDLE handle;      /* The ADXL345 driver handle */
    adxl345_handler_t handler;  /* The ADXL345 interrupt handler */
    FAR void *arg;              /* Argument to pass to the interrupt handler */
  };
  
  /****************************************************************************
   * Static Function Prototypes
   ****************************************************************************/
  
  /* IRQ/GPIO access callbacks.  These operations all hidden behind callbacks
   * to isolate the ADXL345 driver from differences in GPIO interrupt handling
   * by varying boards and MCUs.
   *
   *   attach  - Attach the ADXL345 interrupt handler to the GPIO interrupt
   *   enable  - Enable or disable the GPIO interrupt
   *   clear   - Acknowledge/clear any pending GPIO interrupt
   */
  
  static int  adxl345_attach(FAR struct adxl345_config_s *state,
                             adxl345_handler_t handler, FAR void *arg);
  static void adxl345_enable(FAR struct adxl345_config_s *state, bool enable);
  static void adxl345_clear(FAR struct adxl345_config_s *state);
  
  /****************************************************************************
   * Private Data
   ****************************************************************************/
  
  /* A reference to a structure of this type must be passed to the ADXL345
   * driver.  This structure provides information about the configuration
   * of the ADXL345 and provides some board-specific hooks.
   *
   * Memory for this structure is provided by the caller.  It is not copied
   * by the driver and is presumed to persist while the driver is active. The
   * memory must be writable because, under certain circumstances, the driver
   * may modify frequency or X plate resistance values.
   */
  
  static struct kl_adxl345config_s g_adxl345config =
  {
    .config =
    {
  #ifdef CONFIG_ADXL345_I2C
      .address   = ADXL345_ADDR1,
  #endif
      .frequency = CONFIG_ADXL345_FREQUENCY,
  
      .attach    = adxl345_attach,
      .enable    = adxl345_enable,
      .clear     = adxl345_clear,
    },
  };
  
  /****************************************************************************
   * Private Functions
   ****************************************************************************/
  /* This is the ADXL345 Interupt handler */
  
  int adxl345_interrupt(int irq, FAR void *context)
  {
    /* Verify that we have a handler attached */
  
    if (g_adxl345config.handler)
      {
        /* Yes.. forward with interrupt along with its argument */
  
        g_adxl345config.handler(&g_adxl345config.config, g_adxl345config.arg);
      }
  
    return OK;
  }
  
  /* IRQ/GPIO access callbacks.  These operations all hidden behind
   * callbacks to isolate the ADXL345 driver from differences in GPIO
   * interrupt handling by varying boards and MCUs.
   *
   *   attach  - Attach the ADXL345 interrupt handler to the GPIO interrupt
   *   enable  - Enable or disable the GPIO interrupt
   *   clear   - Acknowledge/clear any pending GPIO interrupt
   */
  
  static int adxl345_attach(FAR struct adxl345_config_s *state,
                             adxl345_handler_t handler, FAR void *arg)
  {
    FAR struct kl_adxl345config_s *priv = (FAR struct kl_adxl345config_s *)state;
  
    sninfo("Saving handler %p\n", handler);
    DEBUGASSERT(priv);
  
    /* Just save the handler and its argument.  We will use it when interrupts
     * are enabled
     */
  
    priv->handler = handler;
    priv->arg = arg;
    return OK;
  }
  
  static void adxl345_enable(FAR struct adxl345_config_s *state, bool enable)
  {
    FAR struct kl_adxl345config_s *priv = (FAR struct kl_adxl345config_s *)state;
    irqstate_t flags;
  
    /* Attach and enable, or detach and disable.  Enabling and disabling GPIO
     * interrupts is a multi-step process so the safest thing is to keep
     * interrupts disabled during the reconfiguration.
     */
  
    flags = enter_critical_section();
    if (enable)
      {
        /* Configure the interrupt using the SAVED handler */
  
        kl_configgpio(GPIO_ADXL345_INT1);
        (void)kl_gpioirqattach(GPIO_ADXL345_INT1, adxl345_interrupt);
        kl_gpioirqenable(GPIO_ADXL345_INT1); 
      }
    else
      {
        /* Configure the interrupt with a NULL handler to disable it */
  
        (void)kl_gpioirqattach(GPIO_ADXL345_INT1, NULL);
        kl_gpioirqdisable(GPIO_ADXL345_INT1); 
      }
  
    leave_critical_section(flags);
  }
  
  static void adxl345_clear(FAR struct adxl345_config_s *state)
  {
    /* Does nothing */
  }
  
  /****************************************************************************
   * Public Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Name: adxl345_archinitialize
   *
   * Description:
   *   Each board that supports an adxl345 device must provide this function.
   *   This function is called by application-specific, setup logic to
   *   configure the accelerometer device.  This function will register the
   *   driver as /dev/accelN where N is the minor device number.
   *
   * Input Parameters:
   *   minor   - The input device minor number
   *
   * Returned Value:
   *   Zero is returned on success.  Otherwise, a negated errno value is
   *   returned to indicate the nature of the failure.
   *
   ****************************************************************************/
  
  int adxl345_archinitialize(int minor)
  {
    FAR struct spi_dev_s *dev;
    int ret;
  
    sninfo("minor %d\n", minor);
    DEBUGASSERT(minor == 0);
  
    /* Check if we are already initialized */
  
    if (!g_adxl345config.handle)
      {
        sninfo("Initializing\n");
  
        /* Configure the ADXL345 interrupt pin as an input */
  
        (void)kl_configgpio(GPIO_ADXL345_INT1);
  
        /* Get an instance of the I2C interface */
  
        dev = kl_spibus_initialize(CONFIG_ADXL345_SPIDEV);
        if (!dev)
          {
            snerr("ERROR: Failed to initialize SPI bus %d\n", CONFIG_ADXL345_SPIDEV);
            return -ENODEV;
          }
  
        /* Instantiate the ADXL345 driver */
  
        g_adxl345config.handle =
          adxl345_instantiate(dev, (FAR struct adxl345_config_s *)&g_adxl345config);
        if (!g_adxl345config.handle)
          {
            snerr("ERROR: Failed to instantiate the ADXL345 driver\n");
            return -ENODEV;
          }
  
        /* Initialize and register the ADXL345 driver */
  
        ret = adxl345_register(g_adxl345config.handle, CONFIG_ADXL345_DEVMINOR);
        if (ret < 0)
          {
            snerr("ERROR: Failed to register ADXL345 driver: %d\n", ret);
            return ret;
          }
      }
  
    return OK;
  }
  
  #endif /* CONFIG_SENSORS_ADXL345 */
  