text: /****************************************************************************
   * drivers/analog/dac7554.c
   *
   *   Copyright (C) 2010, 2016, 2018 Gregory Nutt. All rights reserved.
   *   Copyright (C) 2018 Daniel P. Carvalho. All rights reserved.
   *   Copyright (C) 2019 Augusto Fraga Giachero. All rights reserved.
   *   Author:  Augusto Fraga Giachero <afg@augustofg.net>
   *
   * This file is a part of NuttX:
   *
   *   Copyright (C) 2019 Gregory Nutt. All rights reserved.
   *
   * 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 <stdio.h>
  #include <sys/types.h>
  #include <stdint.h>
  #include <stdbool.h>
  #include <errno.h>
  #include <debug.h>
  
  #include <nuttx/kmalloc.h>
  #include <nuttx/arch.h>
  #include <nuttx/analog/dac.h>
  #include <nuttx/spi/spi.h>
  
  /****************************************************************************
   * Preprocessor definitions
   ****************************************************************************/
  
  #if !defined(CONFIG_SPI)
  #  error SPI Support Required.
  #endif
  
  #if defined(CONFIG_DAC7554)
  
  #ifndef CONFIG_DAC7554_SPI_FREQUENCY
  #  define CONFIG_DAC7554_SPI_FREQUENCY 1000000
  #endif
  
  #define DAC7554_SPI_MODE (SPIDEV_MODE2) /* SPI Mode 2: CPOL=1,CPHA=0 */
  
  /****************************************************************************
   * Private Types
   ****************************************************************************/
  
  struct dac7554_dev_s
  {
    FAR struct spi_dev_s *spi;  /* SPI interface */
    int spidev;                 /* SPI Chip Select number */
  };
  
  /****************************************************************************
   * Private Function Prototypes
   ****************************************************************************/
  
  /* I2C Helpers */
  
  /* DAC methods */
  
  static void dac7554_reset(FAR struct dac_dev_s *dev);
  static int  dac7554_setup(FAR struct dac_dev_s *dev);
  static void dac7554_shutdown(FAR struct dac_dev_s *dev);
  static void dac7554_txint(FAR struct dac_dev_s *dev, bool enable);
  static int  dac7554_send(FAR struct dac_dev_s *dev,
                FAR struct dac_msg_s *msg);
  static int  dac7554_ioctl(FAR struct dac_dev_s *dev, int cmd,
                unsigned long arg);
  
  /****************************************************************************
   * Private Data
   ****************************************************************************/
  
  static const struct dac_ops_s g_dacops =
  {
    .ao_reset    = dac7554_reset,
    .ao_setup    = dac7554_setup,
    .ao_shutdown = dac7554_shutdown,
    .ao_txint    = dac7554_txint,
    .ao_send     = dac7554_send,
    .ao_ioctl    = dac7554_ioctl,
  };
  
  /****************************************************************************
   * Private Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Name: dac7554_configspi
   *
   * Description:
   *   Configure the SPI interface
   *
   ****************************************************************************/
  
  static inline void dac7554_configspi(FAR struct spi_dev_s *spi)
  {
    SPI_SETMODE(spi, DAC7554_SPI_MODE);
    SPI_SETBITS(spi, 8);
    SPI_HWFEATURES(spi, 0);
    SPI_SETFREQUENCY(spi, CONFIG_DAC7554_SPI_FREQUENCY);
  }
  
  /****************************************************************************
   * Name: dac7554_reset
   *
   * Description:
   *   Reset the DAC device. Called early to initialize the hardware. This
   *   is called, before ao_setup() and on error conditions.
   *
   ****************************************************************************/
  
  static void dac7554_reset(FAR struct dac_dev_s *dev)
  {
  }
  
  /****************************************************************************
   * Name: dac7554_setup
   *
   * Description:
   *   Configure the DAC. This method is called the first time that the DAC
   *   device is opened.  This will occur when the port is first opened.
   *   This setup includes configuring and attaching DAC interrupts. Interrupts
   *   are all disabled upon return.
   *
   ****************************************************************************/
  
  static int  dac7554_setup(FAR struct dac_dev_s *dev)
  {
    return OK;
  }
  
  /****************************************************************************
   * Name: dac7554_shutdown
   *
   * Description:
   *   Disable the DAC. This method is called when the DAC device is closed.
   *   This method reverses the operation the setup method.
   *
   ****************************************************************************/
  
  static void dac7554_shutdown(FAR struct dac_dev_s *dev)
  {
  }
  
  /****************************************************************************
   * Name: dac7554_txint
   *
   * Description:
   *   Call to enable or disable TX interrupts
   *
   ****************************************************************************/
  
  static void dac7554_txint(FAR struct dac_dev_s *dev, bool enable)
  {
  }
  
  /****************************************************************************
   * Name: dac7554_send
   ****************************************************************************/
  
  static int dac7554_send(FAR struct dac_dev_s *dev, FAR struct dac_msg_s *msg)
  {
    FAR struct dac7554_dev_s *priv = (FAR struct dac7554_dev_s *)dev->ad_priv;
    uint16_t data;
  
    /* Sanity check */
  
    DEBUGASSERT(priv->spi != NULL);
  
    /* Set up message to send */
  
    ainfo("value: %08x\n", msg->am_data);
  
    SPI_LOCK(priv->spi, true);
  
    dac7554_configspi(priv->spi);
  
    data = ((msg->am_data >> 16) & 0x0fff) | ((msg->am_channel & 0x03) << 12) |
      (1 << 15);
  
    SPI_SELECT(priv->spi, priv->spidev, true);
  
    SPI_SEND(priv->spi, (data >> 8));
    SPI_SEND(priv->spi, (data & 0xff));
  
    SPI_SELECT(priv->spi, priv->spidev, false);
  
    SPI_LOCK(priv->spi, false);
  
    dac_txdone(dev);
    return 0;
  }
  
  /****************************************************************************
   * Name: dac7554_ioctl
   ****************************************************************************/
  
  static int dac7554_ioctl(FAR struct dac_dev_s *dev, int cmd,
                           unsigned long arg)
  {
    return -ENOTTY;
  }
  
  /****************************************************************************
   * Public Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Name: dac7554_initialize
   *
   * Description:
   *   Initialize DAC
   *
   * Input Parameters:
   *   Port number (for hardware that has multiple DAC interfaces)
   *
   * Returned Value:
   *   Valid DAC7554 device structure reference on success; a NULL on failure
   *
   ****************************************************************************/
  
  FAR struct dac_dev_s *dac7554_initialize(FAR struct spi_dev_s *spi,
                                           int spidev)
  {
    FAR struct dac7554_dev_s *priv;
    FAR struct dac_dev_s *g_dacdev;
  
    /* Sanity check */
  
    DEBUGASSERT(spi != NULL);
  
    /* Initialize the DAC7554 device structure */
  
    priv =
      (FAR struct dac7554_dev_s *)kmm_malloc(sizeof(struct dac7554_dev_s));
    priv->spi = spi;
    priv->spidev = spidev;
  
    g_dacdev = (FAR struct dac_dev_s *)kmm_malloc(sizeof(struct dac_dev_s));
    g_dacdev->ad_ops = &g_dacops;
    g_dacdev->ad_priv = priv;
  
    return g_dacdev;
  }
  
  #endif /* CONFIG_DAC7554 */
  