nuttx/drivers/power/battery_monitor.c

/****************************************************************************
 * drivers/power/battery_monitor.c
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.  The
 * ASF licenses this file to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the
 * License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
 * License for the specific language governing permissions and limitations
 * under the License.
 *
 ****************************************************************************/

/* Upper-half, character driver for battery manager & monitor ICs. */

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <stdbool.h>
#include <errno.h>
#include <debug.h>

#include <nuttx/semaphore.h>
#include <nuttx/fs/fs.h>
#include <nuttx/power/battery_monitor.h>
#include <nuttx/power/battery_ioctl.h>

/* This driver requires:
 *
 * CONFIG_BATTERY_MONITOR - Upper half battery driver support
 */

#if defined(CONFIG_BATTERY_MONITOR)

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/

/****************************************************************************
 * Private
 ****************************************************************************/

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

/* Character driver methods */

static int     bat_monitor_open(FAR struct file *filep);
static int     bat_monitor_close(FAR struct file *filep);
static ssize_t bat_monitor_read(FAR struct file *filep, FAR char *buffer,
                 size_t buflen);
static ssize_t bat_monitor_write(FAR struct file *filep,
                 FAR const char *buffer, size_t buflen);
static int     bat_monitor_ioctl(FAR struct file *filep, int cmd,
                 unsigned long arg);

/****************************************************************************
 * Private Data
 ****************************************************************************/

static const struct file_operations g_batteryops =
{
  bat_monitor_open,
  bat_monitor_close,
  bat_monitor_read,
  bat_monitor_write,
  NULL,
  bat_monitor_ioctl,
  NULL
};

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

/****************************************************************************
 * Name: bat_monitor_open
 *
 * Description:
 *   This function is called whenever the battery device is opened.
 *
 ****************************************************************************/

static int bat_monitor_open(FAR struct file *filep)
{
  return OK;
}

/****************************************************************************
 * Name: bat_monitor_close
 *
 * Description:
 *   This routine is called when the battery device is closed.
 *
 ****************************************************************************/

static int bat_monitor_close(FAR struct file *filep)
{
  return OK;
}

/****************************************************************************
 * Name: bat_monitor_read
 ****************************************************************************/

static ssize_t bat_monitor_read(FAR struct file *filep, FAR char *buffer,
                                size_t buflen)
{
  /* Return nothing read */

  return 0;
}

/****************************************************************************
 * Name: bat_monitor_write
 ****************************************************************************/

static ssize_t bat_monitor_write(FAR struct file *filep,
                                 FAR const char *buffer, size_t buflen)
{
  /* Return nothing written */

  return 0;
}

/****************************************************************************
 * Name: bat_monitor_ioctl
 ****************************************************************************/

static int bat_monitor_ioctl(FAR struct file *filep, int cmd,
                             unsigned long arg)
{
  FAR struct inode *inode = filep->f_inode;
  FAR struct battery_monitor_dev_s *dev  = inode->i_private;
  int ret;

  /* Enforce mutually exclusive access to the battery driver */

  ret = nxsem_wait(&dev->batsem);
  if (ret < 0)
    {
      return ret; /* Probably -EINTR */
    }

  /* Process the IOCTL command */

  ret = -EINVAL;  /* Assume a bad argument */
  switch (cmd)
    {
      case BATIOC_STATE:
        {
          FAR int *ptr = (FAR int *)((uintptr_t)arg);
          if (ptr)
            {
              ret = dev->ops->state(dev, ptr);
            }
        }
        break;

      case BATIOC_HEALTH:
        {
          FAR int *ptr = (FAR int *)((uintptr_t)arg);
          if (ptr)
            {
              ret = dev->ops->health(dev, ptr);
            }
        }
        break;

      case BATIOC_ONLINE:
        {
          FAR bool *ptr = (FAR bool *)((uintptr_t)arg);
          if (ptr)
            {
              ret = dev->ops->online(dev, ptr);
            }
        }
        break;

      case BATIOC_VOLTAGE:
        {
          FAR int *voltsp = (FAR int *)((uintptr_t)arg);
          if (voltsp)
            {
              ret = dev->ops->voltage(dev, voltsp);
            }
        }
        break;

      case BATIOC_CURRENT:
        {
          FAR struct battery_monitor_current_s *current =
              (FAR struct battery_monitor_current_s *)((uintptr_t)arg);
          if (current)
            {
              ret = dev->ops->current(dev, current);
            }
        }
        break;

      case BATIOC_OPERATE:
        {
          FAR int *ptr = (FAR int *)((uintptr_t)arg);
          if (ptr)
            {
              ret = dev->ops->operate(dev, (uintptr_t)arg);
            }
        }
        break;

      case BATIOC_CELLVOLTAGE:
        {
          FAR struct battery_monitor_voltage_s *ptr =
              (FAR struct battery_monitor_voltage_s *)((uintptr_t)arg);
          if (ptr)
            {
              ret = dev->ops->cell_voltage(dev, ptr);
            }
        }
        break;

      case BATIOC_BALANCE:
        {
          FAR struct battery_monitor_balance_s *ptr =
              (FAR struct battery_monitor_balance_s *)((uintptr_t)arg);
          if (ptr)
            {
              ret = dev->ops->balance(dev, ptr);
            }
        }
        break;

      case BATIOC_SHUTDOWN:
        {
          /* Options are not currently used by shutdown */

          ret = dev->ops->shutdown(dev, (uintptr_t)arg);
        }
        break;

      case BATIOC_SETLIMITS:
        {
          FAR struct battery_monitor_limits_s *ptr =
              (FAR struct battery_monitor_limits_s *)((uintptr_t)arg);
          if (ptr)
            {
              ret = dev->ops->setlimits(dev, ptr);
            }
        }
        break;

      case BATIOC_CHGDSG:
        {
          FAR struct battery_monitor_switches_s *ptr =
              (FAR struct battery_monitor_switches_s *)((uintptr_t)arg);
          if (ptr)
            {
              ret = dev->ops->chgdsg(dev, ptr);
            }
        }
        break;

      case BATIOC_CLEARFAULTS:
        {
          /* Options are not currently used by clear faults operation */

          ret = dev->ops->clearfaults(dev, (uintptr_t)arg);
        }
        break;

      case BATIOC_TEMPERATURE:
        {
          FAR struct battery_monitor_temperature_s *ptr =
              (FAR struct battery_monitor_temperature_s *)((uintptr_t)arg);
          if (ptr)
            {
              ret = dev->ops->temperature(dev, ptr);
            }
        }
        break;

      case BATIOC_COULOMBS:
        {
          FAR int *coulombp = (FAR int *)((uintptr_t)arg);
          if (coulombp)
            {
              ret = dev->ops->coulombs(dev, coulombp);
            }
        }
        break;

      default:
        _err("ERROR: Unrecognized cmd: %d\n", cmd);
        ret = -ENOTTY;
        break;
    }

  nxsem_post(&dev->batsem);
  return ret;
}

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

/****************************************************************************
 * Name: battery_monitor_register
 *
 * Description:
 *   Register a lower half battery driver with the common, upper-half
 *   battery driver.
 *
 * Input Parameters:
 *   devpath - The location in the pseudo-filesystem to create the driver.
 *     Recommended standard is "/dev/bat0", "/dev/bat1", etc.
 *   dev - An instance of the battery state structure .
 *
 * Returned Value:
 *    Zero on success or a negated errno value on failure.
 *
 ****************************************************************************/

int battery_monitor_register(FAR const char *devpath,
                             FAR struct battery_monitor_dev_s *dev)
{
  int ret;

  /* Initialize the semaphore */

  nxsem_init(&dev->batsem, 0, 1);

  /* Register the character driver */

  ret = register_driver(devpath, &g_batteryops, 0555, dev);
  if (ret < 0)
    {
      _err("ERROR: Failed to register driver: %d\n", ret);
    }

  return ret;
}
#endif /* CONFIG_BATTERY_MONITOR */