nuttx/configs/u-blox-c027/src/lpc17_ubxmdm.c

/****************************************************************************
 * config/u-blox-c027/src/lpc17_ubxmdm.c
 *
 *   Copyright (C) 2016 Vladimir Komendantskiy. All rights reserved.
 *   Author: Vladimir Komendantskiy <vladimir@moixaenergy.com>
 *
 * 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 <sys/types.h>
#include <stdbool.h>
#include <string.h>
#include <poll.h>
#include <errno.h>
#include <unistd.h>

#include <nuttx/fs/fs.h>
#include <nuttx/irq.h>
#include <nuttx/kmalloc.h>
#include <nuttx/modem/u-blox.h>

#include <arch/board/board.h>
#include "lpc17_gpio.h"
#include "u-blox-c027.h"

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/
/* Debug ********************************************************************/
/* Non-standard debug that may be enabled just for testing the modem driver */

#ifdef CONFIG_MODEM_U_BLOX_DEBUG
#  define m_err     _err
#  define m_info    _info
#else
#  define m_err(x...)
#  define m_info(x...)
#endif

#define UBXMDM_REGISTER_COUNT                           \
  (sizeof(lpc17_ubxmdm_name_pins) /                     \
   sizeof(struct lpc17_name_pin))

/****************************************************************************
 * Private Types
 ****************************************************************************/

/* Core interface pin connections.  These do not include UART or USB pins. */

struct lpc17_ubxmdm_pins
{
  lpc17_pinset_t ldo_enable;
  lpc17_pinset_t power_on_n;
  lpc17_pinset_t reset_n;
  lpc17_pinset_t shifter_en_n;
  lpc17_pinset_t usb_detect;
};

/* This structure type provides the private representation of the "lower-half"
 * driver state.  This type must be coercible to type 'ubxmdm_lower'.
 */

struct lpc17_ubxmdm_lower
{
  FAR const struct ubxmdm_ops* ops;  /* Lower half operations */

  /* Private, architecture-specific information. */

  FAR const struct lpc17_ubxmdm_pins* pins;
  bool usb_used;
};

/* Pair type for associating a register name to a pin. */

struct lpc17_name_pin
{
  const char name[3];
  const lpc17_pinset_t pin;
};

/****************************************************************************
 * Private Function Prototypes
 ****************************************************************************/

/* "Lower half" driver methods **********************************************/

static int lpc17_poweron  (FAR struct ubxmdm_lower* lower);
static int lpc17_poweroff (FAR struct ubxmdm_lower* lower);
static int lpc17_reset    (FAR struct ubxmdm_lower* lower);
static int lpc17_getstatus(FAR struct ubxmdm_lower* lower,
                           FAR struct ubxmdm_status* status);
static int lpc17_ioctl    (FAR struct ubxmdm_lower* lower,
                           int cmd,
                           unsigned long arg);

/* "Lower half" driver state */

static struct lpc17_ubxmdm_lower lpc17_ubxmdm_lower;

/****************************************************************************
 * Private Data
 ****************************************************************************/
/* "Lower half" driver methods */

static const struct lpc17_ubxmdm_pins lpc17_ubxmdm_pins =
{
  .ldo_enable   = C027_MDMLDOEN,
  .power_on_n   = C027_MDMPWR,
  .reset_n      = C027_MDMRST,
  .shifter_en_n = C027_MDMLVLOE,
  .usb_detect   = C027_MDMUSBDET,
};

static const struct ubxmdm_ops lpc17_ubxmdm_ops =
{
  .poweron      = lpc17_poweron,
  .poweroff     = lpc17_poweroff,
  .reset        = lpc17_reset,
  .getstatus    = lpc17_getstatus,
  .ioctl        = lpc17_ioctl,
};

static const struct lpc17_name_pin lpc17_ubxmdm_name_pins[] =
{
  {{'T','X','D'}, GPIO_UART1_TXD},
  {{'R','X','D'}, GPIO_UART1_RXD},
  {{'C','T','S'}, GPIO_UART1_CTS},
  {{'R','T','S'}, GPIO_UART1_RTS},
  {{'D','C','D'}, GPIO_UART1_DCD},
  {{'D','S','R'}, GPIO_UART1_DSR},
  {{'D','T','R'}, GPIO_UART1_DTR},
  {{'R','I',' '}, GPIO_UART1_RI },
  {{'I','O','1'}, C027_MDMGPIO1 },
  {{'R','S','T'}, C027_MDMRST   },
  {{'P','W','R'}, C027_MDMPWR   },
  {{'D','E','T'}, C027_MDMUSBDET},
  {{'L','D','O'}, C027_MDMLDOEN },
  {{'L','V','L'}, C027_MDMLVLOE },
};

/****************************************************************************
 * Private Functions
 ****************************************************************************/

static int lpc17_poweron(FAR struct ubxmdm_lower* lower)
{
  FAR struct lpc17_ubxmdm_lower* priv =
    (FAR struct lpc17_ubxmdm_lower*) lower;
  lpc17_pinset_t usb_detect_val;

  lpc17_configgpio(priv->pins->reset_n      | GPIO_VALUE_ONE);  /* Modem not in reset */
  lpc17_configgpio(priv->pins->power_on_n   | GPIO_VALUE_ZERO); /* Switch closed to GND */
  usleep(10 * 1000);  /* Min. time for power_on_n being low is 5 ms */

  if (priv->usb_used)
    {
      usb_detect_val = GPIO_VALUE_ONE;  /* USB sense on */
    }
  else
    {
      usb_detect_val = GPIO_VALUE_ZERO; /* USB sense off */
    }

  lpc17_configgpio(priv->pins->usb_detect   | usb_detect_val);

  lpc17_configgpio(priv->pins->ldo_enable   | GPIO_VALUE_ONE);  /* LDO enabled */
  usleep(1 * 1000);  /* Delay to obtain correct voltage on shifters */

  lpc17_configgpio(priv->pins->shifter_en_n | GPIO_VALUE_ZERO); /* UART shifter enabled */
/* lpc17_configgpio(priv->pins->power_on_n  | GPIO_VALUE_ONE);   * Stop current through switch */

  return OK;
}

static int lpc17_poweroff(FAR struct ubxmdm_lower* lower)
{
  FAR struct lpc17_ubxmdm_lower* priv =
    (FAR struct lpc17_ubxmdm_lower*) lower;

  lpc17_configgpio(priv->pins->ldo_enable   | GPIO_VALUE_ZERO); /* LDO disabled */
  lpc17_configgpio(priv->pins->reset_n      | GPIO_VALUE_ONE);  /* Modem not in reset */
  lpc17_configgpio(priv->pins->power_on_n   | GPIO_VALUE_ONE);  /* Switch open */
  lpc17_configgpio(priv->pins->shifter_en_n | GPIO_VALUE_ONE);  /* UART shifter disabled */
  lpc17_configgpio(priv->pins->usb_detect   | GPIO_VALUE_ZERO); /* USB sense off */

  return OK;
}

static int lpc17_reset(FAR struct ubxmdm_lower* lower)
{
  FAR struct lpc17_ubxmdm_lower* priv =
    (FAR struct lpc17_ubxmdm_lower*) lower;

  lpc17_configgpio(priv->pins->reset_n | GPIO_VALUE_ZERO); /* Modem in reset */
  usleep(75 * 1000);  /* The minimum reset_n low time is 50 ms */
  lpc17_configgpio(priv->pins->reset_n | GPIO_VALUE_ONE);  /* Modem not in reset */

  return OK;
}

static int lpc17_getstatus(FAR struct ubxmdm_lower* lower,
                           FAR struct ubxmdm_status* status)
{
  FAR struct lpc17_ubxmdm_lower* priv =
    (FAR struct lpc17_ubxmdm_lower*) lower;
  int i;

  status->on =
    lpc17_gpioread(priv->pins->ldo_enable) &&
    lpc17_gpioread(priv->pins->reset_n) &&
    !lpc17_gpioread(priv->pins->shifter_en_n);

  DEBUGASSERT(status->register_values_size >= UBXMDM_REGISTER_COUNT);
  status->register_values_size = UBXMDM_REGISTER_COUNT;

  for (i = 0; i < UBXMDM_REGISTER_COUNT; i++)
    {
      strncpy(status->register_values[i].name,
              lpc17_ubxmdm_name_pins[i].name,
              3);
      status->register_values[i].val =
        lpc17_gpioread(lpc17_ubxmdm_name_pins[i].pin);
    }

  return OK;
}

static int lpc17_ioctl(FAR struct ubxmdm_lower* lower,
                       int cmd,
                       unsigned long arg)
{
  /* No platform-specific IOCTL at the moment. */

  return -ENOSYS;
}

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: lpc17_ubxmdm_init
 *
 * Description:
 *   Initialize the modem.  The modem is initialized and
 *   registered at '/dev/ubxmdm'.
 *
 * Input Parameters:
 *   usb_used - enables the USB sense pin if 'true'
 *
 * Returned Values:
 *   None
 *
 ****************************************************************************/

void lpc17_ubxmdm_init(bool usb_used)
{
  FAR struct lpc17_ubxmdm_lower* priv = &lpc17_ubxmdm_lower;

  DEBUGASSERT(priv->ops == NULL && priv->pins == NULL);

  /* Initialize the driver state structure.  Here we assume: (1) the state
   * structure lies in .bss and was zeroed at reset time.  (2) This function
   * is only called once so it is never necessary to re-zero the structure.
   */

  priv->ops      = &lpc17_ubxmdm_ops;
  priv->pins     = &lpc17_ubxmdm_pins;
  priv->usb_used = usb_used;

  lpc17_poweroff((FAR struct ubxmdm_lower*) priv);

  (void) ubxmdm_register("/dev/ubxmdm", (FAR struct ubxmdm_lower*) priv);
}