/*

   *  battery.c - ACPI Battery Driver (Revision: 2.0)

   *

   *  Copyright (C) 2007 Alexey Starikovskiy <astarikovskiy@suse.de>
   *  Copyright (C) 2004-2007 Vladimir Lebedev <vladimir.p.lebedev@intel.com>

   *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   *
   * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   *
   *  This program is free software; you can redistribute it and/or modify
   *  it under the terms of the GNU General Public License as published by
   *  the Free Software Foundation; either version 2 of the License, or (at
   *  your option) any later version.
   *
   *  This program is distributed in the hope that it will be useful, but
   *  WITHOUT ANY WARRANTY; without even the implied warranty of
   *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   *  General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License along
   *  with this program; if not, write to the Free Software Foundation, Inc.,
   *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
   *
   * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   */
  
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/types.h>

  #include <linux/jiffies.h>

  #include <linux/async.h>

  #include <linux/dmi.h>

  #include <linux/slab.h>

  #include <linux/suspend.h>

  #ifdef CONFIG_ACPI_PROCFS_POWER

  #include <linux/proc_fs.h>
  #include <linux/seq_file.h>
  #include <asm/uaccess.h>

  #endif

  
  #include <acpi/acpi_bus.h>
  #include <acpi/acpi_drivers.h>

  #include <linux/power_supply.h>

  #define PREFIX "ACPI: "

  #define ACPI_BATTERY_VALUE_UNKNOWN 0xFFFFFFFF

  #define ACPI_BATTERY_CLASS		"battery"

  #define ACPI_BATTERY_DEVICE_NAME	"Battery"

  #define ACPI_BATTERY_NOTIFY_STATUS	0x80
  #define ACPI_BATTERY_NOTIFY_INFO	0x81

  #define ACPI_BATTERY_NOTIFY_THRESHOLD   0x82

  /* Battery power unit: 0 means mW, 1 means mA */
  #define ACPI_BATTERY_POWER_UNIT_MA	1

  #define _COMPONENT		ACPI_BATTERY_COMPONENT

  ACPI_MODULE_NAME("battery");

  MODULE_AUTHOR("Paul Diefenbaugh");

  MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");

  MODULE_DESCRIPTION("ACPI Battery Driver");

  MODULE_LICENSE("GPL");

  static unsigned int cache_time = 1000;
  module_param(cache_time, uint, 0644);
  MODULE_PARM_DESC(cache_time, "cache time in milliseconds");

  #ifdef CONFIG_ACPI_PROCFS_POWER

  extern struct proc_dir_entry *acpi_lock_battery_dir(void);
  extern void *acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir);

  enum acpi_battery_files {
  	info_tag = 0,
  	state_tag,
  	alarm_tag,
  	ACPI_BATTERY_NUMFILES,
  };
  
  #endif

  static const struct acpi_device_id battery_device_ids[] = {
  	{"PNP0C0A", 0},
  	{"", 0},
  };

  MODULE_DEVICE_TABLE(acpi, battery_device_ids);

  enum {
  	ACPI_BATTERY_ALARM_PRESENT,

  	ACPI_BATTERY_XINFO_PRESENT,

  	ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY,

  };

  struct acpi_battery {

  	struct mutex lock;

  	struct mutex sysfs_lock;

  	struct power_supply bat;

  	struct acpi_device *device;

  	struct notifier_block pm_nb;

  	unsigned long update_time;

  	int rate_now;

  	int capacity_now;
  	int voltage_now;

  	int design_capacity;

  	int full_charge_capacity;

  	int technology;
  	int design_voltage;
  	int design_capacity_warning;
  	int design_capacity_low;

  	int cycle_count;
  	int measurement_accuracy;
  	int max_sampling_time;
  	int min_sampling_time;
  	int max_averaging_interval;
  	int min_averaging_interval;

  	int capacity_granularity_1;
  	int capacity_granularity_2;

  	int alarm;

  	char model_number[32];
  	char serial_number[32];
  	char type[32];
  	char oem_info[32];

  	int state;
  	int power_unit;

  	unsigned long flags;

  };

  #define to_acpi_battery(x) container_of(x, struct acpi_battery, bat)

  inline int acpi_battery_present(struct acpi_battery *battery)

  {

  	return battery->device->status.battery_present;
  }

  static int acpi_battery_technology(struct acpi_battery *battery)
  {
  	if (!strcasecmp("NiCd", battery->type))
  		return POWER_SUPPLY_TECHNOLOGY_NiCd;
  	if (!strcasecmp("NiMH", battery->type))
  		return POWER_SUPPLY_TECHNOLOGY_NiMH;
  	if (!strcasecmp("LION", battery->type))
  		return POWER_SUPPLY_TECHNOLOGY_LION;

  	if (!strncasecmp("LI-ION", battery->type, 6))

  		return POWER_SUPPLY_TECHNOLOGY_LION;

  	if (!strcasecmp("LiP", battery->type))
  		return POWER_SUPPLY_TECHNOLOGY_LIPO;
  	return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
  }

  static int acpi_battery_get_state(struct acpi_battery *battery);

  static int acpi_battery_is_charged(struct acpi_battery *battery)
  {
  	/* either charging or discharging */
  	if (battery->state != 0)
  		return 0;
  
  	/* battery not reporting charge */
  	if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
  	    battery->capacity_now == 0)
  		return 0;
  
  	/* good batteries update full_charge as the batteries degrade */
  	if (battery->full_charge_capacity == battery->capacity_now)
  		return 1;
  
  	/* fallback to using design values for broken batteries */
  	if (battery->design_capacity == battery->capacity_now)
  		return 1;
  
  	/* we don't do any sort of metric based on percentages */
  	return 0;
  }

  static int acpi_battery_get_property(struct power_supply *psy,
  				     enum power_supply_property psp,
  				     union power_supply_propval *val)
  {

  	int ret = 0;

  	struct acpi_battery *battery = to_acpi_battery(psy);

  	if (acpi_battery_present(battery)) {
  		/* run battery update only if it is present */
  		acpi_battery_get_state(battery);
  	} else if (psp != POWER_SUPPLY_PROP_PRESENT)

  		return -ENODEV;
  	switch (psp) {
  	case POWER_SUPPLY_PROP_STATUS:
  		if (battery->state & 0x01)
  			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
  		else if (battery->state & 0x02)
  			val->intval = POWER_SUPPLY_STATUS_CHARGING;

  		else if (acpi_battery_is_charged(battery))

  			val->intval = POWER_SUPPLY_STATUS_FULL;

  		else
  			val->intval = POWER_SUPPLY_STATUS_UNKNOWN;

  		break;
  	case POWER_SUPPLY_PROP_PRESENT:
  		val->intval = acpi_battery_present(battery);
  		break;
  	case POWER_SUPPLY_PROP_TECHNOLOGY:
  		val->intval = acpi_battery_technology(battery);
  		break;

  	case POWER_SUPPLY_PROP_CYCLE_COUNT:
  		val->intval = battery->cycle_count;
  		break;

  	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:

  		if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
  			ret = -ENODEV;
  		else
  			val->intval = battery->design_voltage * 1000;

  		break;
  	case POWER_SUPPLY_PROP_VOLTAGE_NOW:

  		if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
  			ret = -ENODEV;
  		else
  			val->intval = battery->voltage_now * 1000;

  		break;
  	case POWER_SUPPLY_PROP_CURRENT_NOW:

  	case POWER_SUPPLY_PROP_POWER_NOW:

  		if (battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN)
  			ret = -ENODEV;
  		else
  			val->intval = battery->rate_now * 1000;

  		break;
  	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
  	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:

  		if (battery->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
  			ret = -ENODEV;
  		else
  			val->intval = battery->design_capacity * 1000;

  		break;
  	case POWER_SUPPLY_PROP_CHARGE_FULL:
  	case POWER_SUPPLY_PROP_ENERGY_FULL:

  		if (battery->full_charge_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
  			ret = -ENODEV;
  		else
  			val->intval = battery->full_charge_capacity * 1000;

  		break;
  	case POWER_SUPPLY_PROP_CHARGE_NOW:
  	case POWER_SUPPLY_PROP_ENERGY_NOW:

  		if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
  			ret = -ENODEV;
  		else
  			val->intval = battery->capacity_now * 1000;

  		break;
  	case POWER_SUPPLY_PROP_MODEL_NAME:
  		val->strval = battery->model_number;
  		break;
  	case POWER_SUPPLY_PROP_MANUFACTURER:
  		val->strval = battery->oem_info;
  		break;

  	case POWER_SUPPLY_PROP_SERIAL_NUMBER:
  		val->strval = battery->serial_number;
  		break;

  	default:

  		ret = -EINVAL;

  	}

  	return ret;

  }
  
  static enum power_supply_property charge_battery_props[] = {
  	POWER_SUPPLY_PROP_STATUS,
  	POWER_SUPPLY_PROP_PRESENT,
  	POWER_SUPPLY_PROP_TECHNOLOGY,

  	POWER_SUPPLY_PROP_CYCLE_COUNT,

  	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
  	POWER_SUPPLY_PROP_VOLTAGE_NOW,
  	POWER_SUPPLY_PROP_CURRENT_NOW,
  	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
  	POWER_SUPPLY_PROP_CHARGE_FULL,
  	POWER_SUPPLY_PROP_CHARGE_NOW,
  	POWER_SUPPLY_PROP_MODEL_NAME,
  	POWER_SUPPLY_PROP_MANUFACTURER,

  	POWER_SUPPLY_PROP_SERIAL_NUMBER,

  };
  
  static enum power_supply_property energy_battery_props[] = {
  	POWER_SUPPLY_PROP_STATUS,
  	POWER_SUPPLY_PROP_PRESENT,
  	POWER_SUPPLY_PROP_TECHNOLOGY,

  	POWER_SUPPLY_PROP_CYCLE_COUNT,

  	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
  	POWER_SUPPLY_PROP_VOLTAGE_NOW,

  	POWER_SUPPLY_PROP_POWER_NOW,

  	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
  	POWER_SUPPLY_PROP_ENERGY_FULL,
  	POWER_SUPPLY_PROP_ENERGY_NOW,
  	POWER_SUPPLY_PROP_MODEL_NAME,
  	POWER_SUPPLY_PROP_MANUFACTURER,

  	POWER_SUPPLY_PROP_SERIAL_NUMBER,

  };

  #ifdef CONFIG_ACPI_PROCFS_POWER

  inline char *acpi_battery_units(struct acpi_battery *battery)

  {

  	return (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA) ?
  		"mA" : "mW";

  }

  #endif

  /* --------------------------------------------------------------------------
                                 Battery Management
     -------------------------------------------------------------------------- */

  struct acpi_offsets {
  	size_t offset;		/* offset inside struct acpi_sbs_battery */
  	u8 mode;		/* int or string? */
  };

  static struct acpi_offsets state_offsets[] = {
  	{offsetof(struct acpi_battery, state), 0},

  	{offsetof(struct acpi_battery, rate_now), 0},

  	{offsetof(struct acpi_battery, capacity_now), 0},
  	{offsetof(struct acpi_battery, voltage_now), 0},

  };

  static struct acpi_offsets info_offsets[] = {
  	{offsetof(struct acpi_battery, power_unit), 0},
  	{offsetof(struct acpi_battery, design_capacity), 0},

  	{offsetof(struct acpi_battery, full_charge_capacity), 0},

  	{offsetof(struct acpi_battery, technology), 0},
  	{offsetof(struct acpi_battery, design_voltage), 0},
  	{offsetof(struct acpi_battery, design_capacity_warning), 0},
  	{offsetof(struct acpi_battery, design_capacity_low), 0},
  	{offsetof(struct acpi_battery, capacity_granularity_1), 0},
  	{offsetof(struct acpi_battery, capacity_granularity_2), 0},
  	{offsetof(struct acpi_battery, model_number), 1},
  	{offsetof(struct acpi_battery, serial_number), 1},
  	{offsetof(struct acpi_battery, type), 1},
  	{offsetof(struct acpi_battery, oem_info), 1},
  };

  static struct acpi_offsets extended_info_offsets[] = {
  	{offsetof(struct acpi_battery, power_unit), 0},
  	{offsetof(struct acpi_battery, design_capacity), 0},
  	{offsetof(struct acpi_battery, full_charge_capacity), 0},
  	{offsetof(struct acpi_battery, technology), 0},
  	{offsetof(struct acpi_battery, design_voltage), 0},
  	{offsetof(struct acpi_battery, design_capacity_warning), 0},
  	{offsetof(struct acpi_battery, design_capacity_low), 0},
  	{offsetof(struct acpi_battery, cycle_count), 0},
  	{offsetof(struct acpi_battery, measurement_accuracy), 0},
  	{offsetof(struct acpi_battery, max_sampling_time), 0},
  	{offsetof(struct acpi_battery, min_sampling_time), 0},
  	{offsetof(struct acpi_battery, max_averaging_interval), 0},
  	{offsetof(struct acpi_battery, min_averaging_interval), 0},
  	{offsetof(struct acpi_battery, capacity_granularity_1), 0},
  	{offsetof(struct acpi_battery, capacity_granularity_2), 0},
  	{offsetof(struct acpi_battery, model_number), 1},
  	{offsetof(struct acpi_battery, serial_number), 1},
  	{offsetof(struct acpi_battery, type), 1},
  	{offsetof(struct acpi_battery, oem_info), 1},
  };

  static int extract_package(struct acpi_battery *battery,
  			   union acpi_object *package,
  			   struct acpi_offsets *offsets, int num)
  {

  	int i;

  	union acpi_object *element;
  	if (package->type != ACPI_TYPE_PACKAGE)
  		return -EFAULT;
  	for (i = 0; i < num; ++i) {
  		if (package->package.count <= i)
  			return -EFAULT;
  		element = &package->package.elements[i];
  		if (offsets[i].mode) {

  			u8 *ptr = (u8 *)battery + offsets[i].offset;
  			if (element->type == ACPI_TYPE_STRING ||
  			    element->type == ACPI_TYPE_BUFFER)
  				strncpy(ptr, element->string.pointer, 32);
  			else if (element->type == ACPI_TYPE_INTEGER) {
  				strncpy(ptr, (u8 *)&element->integer.value,

  					sizeof(u64));
  				ptr[sizeof(u64)] = 0;

  			} else
  				*ptr = 0; /* don't have value */

  		} else {

  			int *x = (int *)((u8 *)battery + offsets[i].offset);
  			*x = (element->type == ACPI_TYPE_INTEGER) ?
  				element->integer.value : -1;

  		}

  	}

  	return 0;
  }
  
  static int acpi_battery_get_status(struct acpi_battery *battery)
  {

  	if (acpi_bus_get_status(battery->device)) {

  		ACPI_EXCEPTION((AE_INFO, AE_ERROR, "Evaluating _STA"));
  		return -ENODEV;
  	}

  	return 0;

  }
  
  static int acpi_battery_get_info(struct acpi_battery *battery)

  {

  	int result = -EFAULT;

  	acpi_status status = 0;

  	char *name = test_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags)?
  			"_BIX" : "_BIF";

  	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };

  	if (!acpi_battery_present(battery))
  		return 0;

  	mutex_lock(&battery->lock);

  	status = acpi_evaluate_object(battery->device->handle, name,
  						NULL, &buffer);

  	mutex_unlock(&battery->lock);

  	if (ACPI_FAILURE(status)) {

  		ACPI_EXCEPTION((AE_INFO, status, "Evaluating %s", name));

  		return -ENODEV;

  	}

  	if (test_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags))
  		result = extract_package(battery, buffer.pointer,
  				extended_info_offsets,
  				ARRAY_SIZE(extended_info_offsets));
  	else
  		result = extract_package(battery, buffer.pointer,
  				info_offsets, ARRAY_SIZE(info_offsets));

  	kfree(buffer.pointer);

  	if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
  		battery->full_charge_capacity = battery->design_capacity;

  	return result;

  }

  static int acpi_battery_get_state(struct acpi_battery *battery)

  {

  	int result = 0;
  	acpi_status status = 0;
  	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };

  	if (!acpi_battery_present(battery))
  		return 0;

  	if (battery->update_time &&
  	    time_before(jiffies, battery->update_time +
  			msecs_to_jiffies(cache_time)))
  		return 0;

  	mutex_lock(&battery->lock);

  	status = acpi_evaluate_object(battery->device->handle, "_BST",

  				      NULL, &buffer);
  	mutex_unlock(&battery->lock);

  	if (ACPI_FAILURE(status)) {

  		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BST"));

  		return -ENODEV;

  	}

  	result = extract_package(battery, buffer.pointer,
  				 state_offsets, ARRAY_SIZE(state_offsets));

  	battery->update_time = jiffies;

  	kfree(buffer.pointer);

  	/* For buggy DSDTs that report negative 16-bit values for either
  	 * charging or discharging current and/or report 0 as 65536
  	 * due to bad math.
  	 */
  	if (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA &&
  		battery->rate_now != ACPI_BATTERY_VALUE_UNKNOWN &&
  		(s16)(battery->rate_now) < 0) {

  		battery->rate_now = abs((s16)battery->rate_now);

  		printk_once(KERN_WARNING FW_BUG "battery: (dis)charge rate"
  			" invalid.
  ");
  	}

  	if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags)
  	    && battery->capacity_now >= 0 && battery->capacity_now <= 100)
  		battery->capacity_now = (battery->capacity_now *
  				battery->full_charge_capacity) / 100;

  	return result;
  }

  static int acpi_battery_set_alarm(struct acpi_battery *battery)

  {

  	acpi_status status = 0;

  	union acpi_object arg0 = { .type = ACPI_TYPE_INTEGER };

  	struct acpi_object_list arg_list = { 1, &arg0 };

  	if (!acpi_battery_present(battery) ||

  	    !test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags))

  		return -ENODEV;

  	arg0.integer.value = battery->alarm;

  	mutex_lock(&battery->lock);

  	status = acpi_evaluate_object(battery->device->handle, "_BTP",
  				 &arg_list, NULL);

  	mutex_unlock(&battery->lock);

  	if (ACPI_FAILURE(status))

  		return -ENODEV;

  	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Alarm set to %d
  ", battery->alarm));

  	return 0;

  }

  static int acpi_battery_init_alarm(struct acpi_battery *battery)

  {

  	acpi_status status = AE_OK;
  	acpi_handle handle = NULL;

  	/* See if alarms are supported, and if so, set default */

  	status = acpi_get_handle(battery->device->handle, "_BTP", &handle);
  	if (ACPI_FAILURE(status)) {

  		clear_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags);

  		return 0;

  	}

  	set_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags);

  	if (!battery->alarm)
  		battery->alarm = battery->design_capacity_warning;

  	return acpi_battery_set_alarm(battery);

  }

  static ssize_t acpi_battery_alarm_show(struct device *dev,
  					struct device_attribute *attr,
  					char *buf)
  {
  	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
  	return sprintf(buf, "%d
  ", battery->alarm * 1000);
  }
  
  static ssize_t acpi_battery_alarm_store(struct device *dev,
  					struct device_attribute *attr,
  					const char *buf, size_t count)
  {
  	unsigned long x;
  	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
  	if (sscanf(buf, "%ld
  ", &x) == 1)
  		battery->alarm = x/1000;
  	if (acpi_battery_present(battery))
  		acpi_battery_set_alarm(battery);
  	return count;
  }
  
  static struct device_attribute alarm_attr = {

  	.attr = {.name = "alarm", .mode = 0644},

  	.show = acpi_battery_alarm_show,
  	.store = acpi_battery_alarm_store,
  };
  
  static int sysfs_add_battery(struct acpi_battery *battery)
  {
  	int result;

  	if (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA) {

  		battery->bat.properties = charge_battery_props;
  		battery->bat.num_properties =
  			ARRAY_SIZE(charge_battery_props);
  	} else {
  		battery->bat.properties = energy_battery_props;
  		battery->bat.num_properties =
  			ARRAY_SIZE(energy_battery_props);
  	}
  
  	battery->bat.name = acpi_device_bid(battery->device);
  	battery->bat.type = POWER_SUPPLY_TYPE_BATTERY;
  	battery->bat.get_property = acpi_battery_get_property;
  
  	result = power_supply_register(&battery->device->dev, &battery->bat);
  	if (result)
  		return result;
  	return device_create_file(battery->bat.dev, &alarm_attr);
  }
  
  static void sysfs_remove_battery(struct acpi_battery *battery)
  {

  	mutex_lock(&battery->sysfs_lock);

  	if (!battery->bat.dev) {

  		mutex_unlock(&battery->sysfs_lock);

  		return;

  	}

  	device_remove_file(battery->bat.dev, &alarm_attr);
  	power_supply_unregister(&battery->bat);

  	battery->bat.dev = NULL;

  	mutex_unlock(&battery->sysfs_lock);

  }

  /*
   * According to the ACPI spec, some kinds of primary batteries can
   * report percentage battery remaining capacity directly to OS.
   * In this case, it reports the Last Full Charged Capacity == 100
   * and BatteryPresentRate == 0xFFFFFFFF.
   *
   * Now we found some battery reports percentage remaining capacity
   * even if it's rechargeable.
   * https://bugzilla.kernel.org/show_bug.cgi?id=15979
   *
   * Handle this correctly so that they won't break userspace.
   */

  static void acpi_battery_quirks(struct acpi_battery *battery)

  {
  	if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
  		return ;
  
          if (battery->full_charge_capacity == 100 &&
              battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN &&
              battery->capacity_now >=0 && battery->capacity_now <= 100) {
  		set_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags);
  		battery->full_charge_capacity = battery->design_capacity;
  		battery->capacity_now = (battery->capacity_now *
  				battery->full_charge_capacity) / 100;
  	}
  }

  static int acpi_battery_update(struct acpi_battery *battery)

  {

  	int result, old_present = acpi_battery_present(battery);

  	result = acpi_battery_get_status(battery);

  	if (result)

  		return result;

  	if (!acpi_battery_present(battery)) {
  		sysfs_remove_battery(battery);

  		battery->update_time = 0;

  		return 0;

  	}

  	if (!battery->update_time ||
  	    old_present != acpi_battery_present(battery)) {

  		result = acpi_battery_get_info(battery);
  		if (result)
  			return result;
  		acpi_battery_init_alarm(battery);
  	}

  	if (!battery->bat.dev) {
  		result = sysfs_add_battery(battery);
  		if (result)
  			return result;
  	}

  	result = acpi_battery_get_state(battery);

  	acpi_battery_quirks(battery);

  	return result;

  }

  static void acpi_battery_refresh(struct acpi_battery *battery)
  {
  	if (!battery->bat.dev)
  		return;
  
  	acpi_battery_get_info(battery);
  	/* The battery may have changed its reporting units. */
  	sysfs_remove_battery(battery);
  	sysfs_add_battery(battery);
  }

  /* --------------------------------------------------------------------------
                                FS Interface (/proc)
     -------------------------------------------------------------------------- */

  #ifdef CONFIG_ACPI_PROCFS_POWER

  static struct proc_dir_entry *acpi_battery_dir;

  static int acpi_battery_print_info(struct seq_file *seq, int result)

  {

  	struct acpi_battery *battery = seq->private;

  	if (result)

  		goto end;

  	seq_printf(seq, "present:                 %s
  ",
  		   acpi_battery_present(battery)?"yes":"no");
  	if (!acpi_battery_present(battery))

  		goto end;

  	if (battery->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)

  		seq_printf(seq, "design capacity:         unknown
  ");
  	else
  		seq_printf(seq, "design capacity:         %d %sh
  ",

  			   battery->design_capacity,
  			   acpi_battery_units(battery));

  	if (battery->full_charge_capacity == ACPI_BATTERY_VALUE_UNKNOWN)

  		seq_printf(seq, "last full capacity:      unknown
  ");
  	else
  		seq_printf(seq, "last full capacity:      %d %sh
  ",

  			   battery->full_charge_capacity,

  			   acpi_battery_units(battery));
  
  	seq_printf(seq, "battery technology:      %srechargeable
  ",
  		   (!battery->technology)?"non-":"");

  	if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)

  		seq_printf(seq, "design voltage:          unknown
  ");
  	else
  		seq_printf(seq, "design voltage:          %d mV
  ",

  			   battery->design_voltage);

  	seq_printf(seq, "design capacity warning: %d %sh
  ",

  		   battery->design_capacity_warning,
  		   acpi_battery_units(battery));

  	seq_printf(seq, "design capacity low:     %d %sh
  ",

  		   battery->design_capacity_low,
  		   acpi_battery_units(battery));

  	seq_printf(seq, "cycle count:		  %i
  ", battery->cycle_count);

  	seq_printf(seq, "capacity granularity 1:  %d %sh
  ",

  		   battery->capacity_granularity_1,
  		   acpi_battery_units(battery));

  	seq_printf(seq, "capacity granularity 2:  %d %sh
  ",

  		   battery->capacity_granularity_2,
  		   acpi_battery_units(battery));

  	seq_printf(seq, "model number:            %s
  ", battery->model_number);
  	seq_printf(seq, "serial number:           %s
  ", battery->serial_number);
  	seq_printf(seq, "battery type:            %s
  ", battery->type);
  	seq_printf(seq, "OEM info:                %s
  ", battery->oem_info);

        end:

  	if (result)
  		seq_printf(seq, "ERROR: Unable to read battery info
  ");

  	return result;
  }

  static int acpi_battery_print_state(struct seq_file *seq, int result)

  {

  	struct acpi_battery *battery = seq->private;

  	if (result)

  		goto end;

  	seq_printf(seq, "present:                 %s
  ",
  		   acpi_battery_present(battery)?"yes":"no");
  	if (!acpi_battery_present(battery))

  		goto end;

  	seq_printf(seq, "capacity state:          %s
  ",
  			(battery->state & 0x04)?"critical":"ok");
  	if ((battery->state & 0x01) && (battery->state & 0x02))

  		seq_printf(seq,
  			   "charging state:          charging/discharging
  ");

  	else if (battery->state & 0x01)

  		seq_printf(seq, "charging state:          discharging
  ");

  	else if (battery->state & 0x02)

  		seq_printf(seq, "charging state:          charging
  ");

  	else

  		seq_printf(seq, "charging state:          charged
  ");

  	if (battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN)

  		seq_printf(seq, "present rate:            unknown
  ");
  	else
  		seq_printf(seq, "present rate:            %d %s
  ",

  			   battery->rate_now, acpi_battery_units(battery));

  	if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)

  		seq_printf(seq, "remaining capacity:      unknown
  ");
  	else
  		seq_printf(seq, "remaining capacity:      %d %sh
  ",

  			   battery->capacity_now, acpi_battery_units(battery));
  	if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)

  		seq_printf(seq, "present voltage:         unknown
  ");
  	else
  		seq_printf(seq, "present voltage:         %d mV
  ",

  			   battery->voltage_now);

        end:

  	if (result)

  		seq_printf(seq, "ERROR: Unable to read battery state
  ");

  
  	return result;
  }

  static int acpi_battery_print_alarm(struct seq_file *seq, int result)

  {

  	struct acpi_battery *battery = seq->private;

  	if (result)

  		goto end;

  	if (!acpi_battery_present(battery)) {

  		seq_printf(seq, "present:                 no
  ");
  		goto end;
  	}

  	seq_printf(seq, "alarm:                   ");
  	if (!battery->alarm)
  		seq_printf(seq, "unsupported
  ");
  	else

  		seq_printf(seq, "%u %sh
  ", battery->alarm,
  				acpi_battery_units(battery));

        end:

  	if (result)
  		seq_printf(seq, "ERROR: Unable to read battery alarm
  ");

  	return result;
  }

  static ssize_t acpi_battery_write_alarm(struct file *file,
  					const char __user * buffer,
  					size_t count, loff_t * ppos)

  {

  	int result = 0;
  	char alarm_string[12] = { '\0' };

  	struct seq_file *m = file->private_data;
  	struct acpi_battery *battery = m->private;

  	if (!battery || (count > sizeof(alarm_string) - 1))

  		return -EINVAL;

  	if (!acpi_battery_present(battery)) {
  		result = -ENODEV;
  		goto end;
  	}

  	if (copy_from_user(alarm_string, buffer, count)) {
  		result = -EFAULT;
  		goto end;
  	}

  	alarm_string[count] = '\0';

  	battery->alarm = simple_strtol(alarm_string, NULL, 0);

  	result = acpi_battery_set_alarm(battery);

        end:

  	if (!result)

  		return count;

  	return result;
  }
  
  typedef int(*print_func)(struct seq_file *seq, int result);

  
  static print_func acpi_print_funcs[ACPI_BATTERY_NUMFILES] = {
  	acpi_battery_print_info,
  	acpi_battery_print_state,
  	acpi_battery_print_alarm,

  };

  static int acpi_battery_read(int fid, struct seq_file *seq)
  {
  	struct acpi_battery *battery = seq->private;

  	int result = acpi_battery_update(battery);

  	return acpi_print_funcs[fid](seq, result);

  }

  #define DECLARE_FILE_FUNCTIONS(_name) \
  static int acpi_battery_read_##_name(struct seq_file *seq, void *offset) \
  { \
  	return acpi_battery_read(_name##_tag, seq); \
  } \
  static int acpi_battery_##_name##_open_fs(struct inode *inode, struct file *file) \
  { \
  	return single_open(file, acpi_battery_read_##_name, PDE(inode)->data); \

  }

  DECLARE_FILE_FUNCTIONS(info);
  DECLARE_FILE_FUNCTIONS(state);
  DECLARE_FILE_FUNCTIONS(alarm);
  
  #undef DECLARE_FILE_FUNCTIONS
  
  #define FILE_DESCRIPTION_RO(_name) \
  	{ \
  	.name = __stringify(_name), \
  	.mode = S_IRUGO, \
  	.ops = { \
  		.open = acpi_battery_##_name##_open_fs, \
  		.read = seq_read, \
  		.llseek = seq_lseek, \
  		.release = single_release, \
  		.owner = THIS_MODULE, \
  		}, \
  	}

  #define FILE_DESCRIPTION_RW(_name) \
  	{ \
  	.name = __stringify(_name), \
  	.mode = S_IFREG | S_IRUGO | S_IWUSR, \
  	.ops = { \
  		.open = acpi_battery_##_name##_open_fs, \
  		.read = seq_read, \
  		.llseek = seq_lseek, \
  		.write = acpi_battery_write_##_name, \
  		.release = single_release, \
  		.owner = THIS_MODULE, \
  		}, \
  	}

  static const struct battery_file {

  	struct file_operations ops;

  	umode_t mode;

  	const char *name;

  } acpi_battery_file[] = {

  	FILE_DESCRIPTION_RO(info),
  	FILE_DESCRIPTION_RO(state),
  	FILE_DESCRIPTION_RW(alarm),

  };

  #undef FILE_DESCRIPTION_RO
  #undef FILE_DESCRIPTION_RW

  static int acpi_battery_add_fs(struct acpi_device *device)

  {

  	struct proc_dir_entry *entry = NULL;

  	int i;

  	printk(KERN_WARNING PREFIX "Deprecated procfs I/F for battery is loaded,"
  			" please retry with CONFIG_ACPI_PROCFS_POWER cleared
  ");

  	if (!acpi_device_dir(device)) {
  		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),

  						     acpi_battery_dir);

  		if (!acpi_device_dir(device))

  			return -ENODEV;

  	}

  	for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i) {

  		entry = proc_create_data(acpi_battery_file[i].name,
  					 acpi_battery_file[i].mode,
  					 acpi_device_dir(device),
  					 &acpi_battery_file[i].ops,
  					 acpi_driver_data(device));

  		if (!entry)
  			return -ENODEV;

  	}

  	return 0;

  }

  static void acpi_battery_remove_fs(struct acpi_device *device)

  {

  	int i;

  	if (!acpi_device_dir(device))
  		return;
  	for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i)
  		remove_proc_entry(acpi_battery_file[i].name,

  				  acpi_device_dir(device));

  	remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
  	acpi_device_dir(device) = NULL;

  }

  #endif

  /* --------------------------------------------------------------------------
                                   Driver Interface
     -------------------------------------------------------------------------- */

  static void acpi_battery_notify(struct acpi_device *device, u32 event)

  {

  	struct acpi_battery *battery = acpi_driver_data(device);

  	struct device *old;

  	if (!battery)

  		return;

  	old = battery->bat.dev;

  	if (event == ACPI_BATTERY_NOTIFY_INFO)
  		acpi_battery_refresh(battery);

  	acpi_battery_update(battery);
  	acpi_bus_generate_proc_event(device, event,
  				     acpi_battery_present(battery));
  	acpi_bus_generate_netlink_event(device->pnp.device_class,

  					dev_name(&device->dev), event,

  					acpi_battery_present(battery));

  	/* acpi_battery_update could remove power_supply object */

  	if (old && battery->bat.dev)

  		power_supply_changed(&battery->bat);

  }

  static int battery_notify(struct notifier_block *nb,
  			       unsigned long mode, void *_unused)
  {
  	struct acpi_battery *battery = container_of(nb, struct acpi_battery,
  						    pm_nb);
  	switch (mode) {

  	case PM_POST_HIBERNATION:

  	case PM_POST_SUSPEND:

  		if (battery->bat.dev) {
  			sysfs_remove_battery(battery);
  			sysfs_add_battery(battery);
  		}

  		break;
  	}
  
  	return 0;
  }

  static int acpi_battery_add(struct acpi_device *device)

  {

  	int result = 0;

  	struct acpi_battery *battery = NULL;

  	acpi_handle handle;

  	if (!device)

  		return -EINVAL;

  	battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);

  	if (!battery)

  		return -ENOMEM;

  	battery->device = device;

  	strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
  	strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);

  	device->driver_data = battery;

  	mutex_init(&battery->lock);

  	mutex_init(&battery->sysfs_lock);

  	if (ACPI_SUCCESS(acpi_get_handle(battery->device->handle,
  			"_BIX", &handle)))
  		set_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags);

  	result = acpi_battery_update(battery);
  	if (result)
  		goto fail;

  #ifdef CONFIG_ACPI_PROCFS_POWER

  	result = acpi_battery_add_fs(device);

  #endif

  	if (result) {

  #ifdef CONFIG_ACPI_PROCFS_POWER

  		acpi_battery_remove_fs(device);

  #endif

  		goto fail;

  	}

  	printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)
  ",
  		ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
  		device->status.battery_present ? "present" : "absent");

  	battery->pm_nb.notifier_call = battery_notify;
  	register_pm_notifier(&battery->pm_nb);

  	return result;

  
  fail:
  	sysfs_remove_battery(battery);
  	mutex_destroy(&battery->lock);

  	mutex_destroy(&battery->sysfs_lock);

  	kfree(battery);
  	return result;

  }

  static int acpi_battery_remove(struct acpi_device *device, int type)

  {

  	struct acpi_battery *battery = NULL;

  	if (!device || !acpi_driver_data(device))

  		return -EINVAL;

  	battery = acpi_driver_data(device);

  	unregister_pm_notifier(&battery->pm_nb);

  #ifdef CONFIG_ACPI_PROCFS_POWER

  	acpi_battery_remove_fs(device);

  #endif

  	sysfs_remove_battery(battery);

  	mutex_destroy(&battery->lock);

  	mutex_destroy(&battery->sysfs_lock);

  	kfree(battery);

  	return 0;

  }

  /* this is needed to learn about changes made in suspended state */

  static int acpi_battery_resume(struct acpi_device *device)

  {
  	struct acpi_battery *battery;

  	if (!device)
  		return -EINVAL;

  	battery = acpi_driver_data(device);
  	battery->update_time = 0;

  	acpi_battery_update(battery);

  	return 0;

  }

  static struct acpi_driver acpi_battery_driver = {
  	.name = "battery",
  	.class = ACPI_BATTERY_CLASS,
  	.ids = battery_device_ids,

  	.flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS,

  	.ops = {
  		.add = acpi_battery_add,
  		.resume = acpi_battery_resume,
  		.remove = acpi_battery_remove,

  		.notify = acpi_battery_notify,

  		},
  };

  static void __init acpi_battery_init_async(void *unused, async_cookie_t cookie)

  {

  	if (acpi_disabled)

  		return;

  #ifdef CONFIG_ACPI_PROCFS_POWER

  	acpi_battery_dir = acpi_lock_battery_dir();

  	if (!acpi_battery_dir)

  		return;

  #endif

  	if (acpi_bus_register_driver(&acpi_battery_driver) < 0) {

  #ifdef CONFIG_ACPI_PROCFS_POWER

  		acpi_unlock_battery_dir(acpi_battery_dir);

  #endif

  		return;

  	}

  	return;
  }
  
  static int __init acpi_battery_init(void)
  {
  	async_schedule(acpi_battery_init_async, NULL);

  	return 0;

  }

  static void __exit acpi_battery_exit(void)

  {

  	acpi_bus_unregister_driver(&acpi_battery_driver);

  #ifdef CONFIG_ACPI_PROCFS_POWER

  	acpi_unlock_battery_dir(acpi_battery_dir);

  #endif

  }

  module_init(acpi_battery_init);
  module_exit(acpi_battery_exit);