/*

   *  sbs.c - ACPI Smart Battery System Driver ($Revision: 2.0 $)

   *

   *  Copyright (c) 2007 Alexey Starikovskiy <astarikovskiy@suse.de>
   *  Copyright (c) 2005-2007 Vladimir Lebedev <vladimir.p.lebedev@intel.com>

   *  Copyright (c) 2005 Rich Townsend <rhdt@bartol.udel.edu>
   *
   * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   *
   *  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/init.h>

  #include <linux/slab.h>

  #include <linux/module.h>
  #include <linux/moduleparam.h>
  #include <linux/kernel.h>

  #ifdef CONFIG_ACPI_PROCFS_POWER

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

  #endif

  #include <linux/acpi.h>

  #include <linux/timer.h>

  #include <linux/jiffies.h>

  #include <linux/delay.h>

  #include <linux/power_supply.h>

  #include "sbshc.h"

  #define PREFIX "ACPI: "

  #define ACPI_SBS_CLASS			"sbs"
  #define ACPI_AC_CLASS			"ac_adapter"
  #define ACPI_BATTERY_CLASS		"battery"

  #define ACPI_SBS_DEVICE_NAME		"Smart Battery System"
  #define ACPI_SBS_FILE_INFO		"info"
  #define ACPI_SBS_FILE_STATE		"state"
  #define ACPI_SBS_FILE_ALARM		"alarm"
  #define ACPI_BATTERY_DIR_NAME		"BAT%i"
  #define ACPI_AC_DIR_NAME		"AC0"

  #define ACPI_SBS_NOTIFY_STATUS		0x80
  #define ACPI_SBS_NOTIFY_INFO		0x81

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

  MODULE_DESCRIPTION("Smart Battery System ACPI interface 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");

  
  extern struct proc_dir_entry *acpi_lock_ac_dir(void);
  extern struct proc_dir_entry *acpi_lock_battery_dir(void);
  extern void acpi_unlock_ac_dir(struct proc_dir_entry *acpi_ac_dir);
  extern void acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir);

  #define MAX_SBS_BAT			4

  #define ACPI_SBS_BLOCK_MAX		32

  static const struct acpi_device_id sbs_device_ids[] = {

  	{"ACPI0002", 0},

  	{"", 0},
  };
  MODULE_DEVICE_TABLE(acpi, sbs_device_ids);

  struct acpi_battery {

  	struct power_supply bat;

  	struct acpi_sbs *sbs;

  #ifdef CONFIG_ACPI_PROCFS_POWER

  	struct proc_dir_entry *proc_entry;

  #endif

  	unsigned long update_time;
  	char name[8];

  	char manufacturer_name[ACPI_SBS_BLOCK_MAX];
  	char device_name[ACPI_SBS_BLOCK_MAX];
  	char device_chemistry[ACPI_SBS_BLOCK_MAX];

  	u16 alarm_capacity;

  	u16 full_charge_capacity;
  	u16 design_capacity;
  	u16 design_voltage;
  	u16 serial_number;

  	u16 cycle_count;
  	u16 temp_now;

  	u16 voltage_now;

  	s16 rate_now;
  	s16 rate_avg;

  	u16 capacity_now;

  	u16 state_of_charge;

  	u16 state;

  	u16 mode;

  	u16 spec;

  	u8 id;

  	u8 present:1;

  	u8 have_sysfs_alarm:1;

  };

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

  struct acpi_sbs {

  	struct power_supply charger;

  	struct acpi_device *device;

  	struct acpi_smb_hc *hc;

  	struct mutex lock;

  #ifdef CONFIG_ACPI_PROCFS_POWER

  	struct proc_dir_entry *charger_entry;

  #endif

  	struct acpi_battery battery[MAX_SBS_BAT];

  	u8 batteries_supported:4;

  	u8 manager_present:1;
  	u8 charger_present:1;

  };

  #define to_acpi_sbs(x) container_of(x, struct acpi_sbs, charger)

  static int acpi_sbs_remove(struct acpi_device *device, int type);
  static int acpi_battery_get_state(struct acpi_battery *battery);

  static inline int battery_scale(int log)

  {

  	int scale = 1;
  	while (log--)
  		scale *= 10;
  	return scale;

  }

  static inline int acpi_battery_vscale(struct acpi_battery *battery)

  {

  	return battery_scale((battery->spec & 0x0f00) >> 8);

  }

  static inline int acpi_battery_ipscale(struct acpi_battery *battery)

  {

  	return battery_scale((battery->spec & 0xf000) >> 12);

  }

  static inline int acpi_battery_mode(struct acpi_battery *battery)

  {

  	return (battery->mode & 0x8000);

  }

  static inline int acpi_battery_scale(struct acpi_battery *battery)

  {

  	return (acpi_battery_mode(battery) ? 10 : 1) *
  	    acpi_battery_ipscale(battery);

  }

  static int sbs_get_ac_property(struct power_supply *psy,
  			       enum power_supply_property psp,
  			       union power_supply_propval *val)
  {
  	struct acpi_sbs *sbs = to_acpi_sbs(psy);
  	switch (psp) {
  	case POWER_SUPPLY_PROP_ONLINE:
  		val->intval = sbs->charger_present;
  		break;
  	default:
  		return -EINVAL;
  	}
  	return 0;
  }
  
  static int acpi_battery_technology(struct acpi_battery *battery)
  {
  	if (!strcasecmp("NiCd", battery->device_chemistry))
  		return POWER_SUPPLY_TECHNOLOGY_NiCd;
  	if (!strcasecmp("NiMH", battery->device_chemistry))
  		return POWER_SUPPLY_TECHNOLOGY_NiMH;
  	if (!strcasecmp("LION", battery->device_chemistry))
  		return POWER_SUPPLY_TECHNOLOGY_LION;
  	if (!strcasecmp("LiP", battery->device_chemistry))
  		return POWER_SUPPLY_TECHNOLOGY_LIPO;
  	return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
  }
  
  static int acpi_sbs_battery_get_property(struct power_supply *psy,
  					 enum power_supply_property psp,
  					 union power_supply_propval *val)
  {
  	struct acpi_battery *battery = to_acpi_battery(psy);
  
  	if ((!battery->present) && psp != POWER_SUPPLY_PROP_PRESENT)
  		return -ENODEV;

  
  	acpi_battery_get_state(battery);

  	switch (psp) {
  	case POWER_SUPPLY_PROP_STATUS:

  		if (battery->rate_now < 0)

  			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;

  		else if (battery->rate_now > 0)

  			val->intval = POWER_SUPPLY_STATUS_CHARGING;
  		else
  			val->intval = POWER_SUPPLY_STATUS_FULL;
  		break;
  	case POWER_SUPPLY_PROP_PRESENT:
  		val->intval = battery->present;
  		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:
  		val->intval = battery->design_voltage *
  			acpi_battery_vscale(battery) * 1000;
  		break;
  	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
  		val->intval = battery->voltage_now *
  				acpi_battery_vscale(battery) * 1000;
  		break;
  	case POWER_SUPPLY_PROP_CURRENT_NOW:

  	case POWER_SUPPLY_PROP_POWER_NOW:
  		val->intval = abs(battery->rate_now) *

  				acpi_battery_ipscale(battery) * 1000;

  		val->intval *= (acpi_battery_mode(battery)) ?
  				(battery->voltage_now *
  				acpi_battery_vscale(battery) / 1000) : 1;

  		break;
  	case POWER_SUPPLY_PROP_CURRENT_AVG:

  	case POWER_SUPPLY_PROP_POWER_AVG:
  		val->intval = abs(battery->rate_avg) *

  				acpi_battery_ipscale(battery) * 1000;

  		val->intval *= (acpi_battery_mode(battery)) ?
  				(battery->voltage_now *
  				acpi_battery_vscale(battery) / 1000) : 1;

  		break;
  	case POWER_SUPPLY_PROP_CAPACITY:
  		val->intval = battery->state_of_charge;
  		break;
  	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
  	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
  		val->intval = battery->design_capacity *
  			acpi_battery_scale(battery) * 1000;
  		break;
  	case POWER_SUPPLY_PROP_CHARGE_FULL:
  	case POWER_SUPPLY_PROP_ENERGY_FULL:
  		val->intval = battery->full_charge_capacity *
  			acpi_battery_scale(battery) * 1000;
  		break;
  	case POWER_SUPPLY_PROP_CHARGE_NOW:
  	case POWER_SUPPLY_PROP_ENERGY_NOW:
  		val->intval = battery->capacity_now *
  				acpi_battery_scale(battery) * 1000;
  		break;
  	case POWER_SUPPLY_PROP_TEMP:
  		val->intval = battery->temp_now - 2730;	// dK -> dC
  		break;
  	case POWER_SUPPLY_PROP_MODEL_NAME:
  		val->strval = battery->device_name;
  		break;
  	case POWER_SUPPLY_PROP_MANUFACTURER:
  		val->strval = battery->manufacturer_name;
  		break;
  	default:
  		return -EINVAL;
  	}
  	return 0;
  }
  
  static enum power_supply_property sbs_ac_props[] = {
  	POWER_SUPPLY_PROP_ONLINE,
  };
  
  static enum power_supply_property sbs_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_CURRENT_AVG,
  	POWER_SUPPLY_PROP_CAPACITY,
  	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
  	POWER_SUPPLY_PROP_CHARGE_FULL,
  	POWER_SUPPLY_PROP_CHARGE_NOW,
  	POWER_SUPPLY_PROP_TEMP,
  	POWER_SUPPLY_PROP_MODEL_NAME,
  	POWER_SUPPLY_PROP_MANUFACTURER,
  };
  
  static enum power_supply_property sbs_energy_battery_props[] = {
  	POWER_SUPPLY_PROP_STATUS,
  	POWER_SUPPLY_PROP_PRESENT,
  	POWER_SUPPLY_PROP_TECHNOLOGY,
  	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
  	POWER_SUPPLY_PROP_VOLTAGE_NOW,
  	POWER_SUPPLY_PROP_CURRENT_NOW,
  	POWER_SUPPLY_PROP_CURRENT_AVG,

  	POWER_SUPPLY_PROP_POWER_NOW,
  	POWER_SUPPLY_PROP_POWER_AVG,

  	POWER_SUPPLY_PROP_CAPACITY,
  	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
  	POWER_SUPPLY_PROP_ENERGY_FULL,
  	POWER_SUPPLY_PROP_ENERGY_NOW,
  	POWER_SUPPLY_PROP_TEMP,
  	POWER_SUPPLY_PROP_MODEL_NAME,
  	POWER_SUPPLY_PROP_MANUFACTURER,
  };

  /* --------------------------------------------------------------------------
                              Smart Battery System Management
     -------------------------------------------------------------------------- */

  struct acpi_battery_reader {
  	u8 command;		/* command for battery */
  	u8 mode;		/* word or block? */
  	size_t offset;		/* offset inside struct acpi_sbs_battery */
  };

  static struct acpi_battery_reader info_readers[] = {
  	{0x01, SMBUS_READ_WORD, offsetof(struct acpi_battery, alarm_capacity)},
  	{0x03, SMBUS_READ_WORD, offsetof(struct acpi_battery, mode)},
  	{0x10, SMBUS_READ_WORD, offsetof(struct acpi_battery, full_charge_capacity)},
  	{0x17, SMBUS_READ_WORD, offsetof(struct acpi_battery, cycle_count)},
  	{0x18, SMBUS_READ_WORD, offsetof(struct acpi_battery, design_capacity)},
  	{0x19, SMBUS_READ_WORD, offsetof(struct acpi_battery, design_voltage)},
  	{0x1a, SMBUS_READ_WORD, offsetof(struct acpi_battery, spec)},
  	{0x1c, SMBUS_READ_WORD, offsetof(struct acpi_battery, serial_number)},
  	{0x20, SMBUS_READ_BLOCK, offsetof(struct acpi_battery, manufacturer_name)},
  	{0x21, SMBUS_READ_BLOCK, offsetof(struct acpi_battery, device_name)},
  	{0x22, SMBUS_READ_BLOCK, offsetof(struct acpi_battery, device_chemistry)},
  };

  static struct acpi_battery_reader state_readers[] = {
  	{0x08, SMBUS_READ_WORD, offsetof(struct acpi_battery, temp_now)},
  	{0x09, SMBUS_READ_WORD, offsetof(struct acpi_battery, voltage_now)},

  	{0x0a, SMBUS_READ_WORD, offsetof(struct acpi_battery, rate_now)},
  	{0x0b, SMBUS_READ_WORD, offsetof(struct acpi_battery, rate_avg)},

  	{0x0f, SMBUS_READ_WORD, offsetof(struct acpi_battery, capacity_now)},
  	{0x0e, SMBUS_READ_WORD, offsetof(struct acpi_battery, state_of_charge)},
  	{0x16, SMBUS_READ_WORD, offsetof(struct acpi_battery, state)},
  };

  static int acpi_manager_get_info(struct acpi_sbs *sbs)

  {

  	int result = 0;

  	u16 battery_system_info;

  	result = acpi_smbus_read(sbs->hc, SMBUS_READ_WORD, ACPI_SBS_MANAGER,

  				 0x04, (u8 *)&battery_system_info);

  	if (!result)
  		sbs->batteries_supported = battery_system_info & 0x000f;

  	return result;

  }
  
  static int acpi_battery_get_info(struct acpi_battery *battery)
  {

  	int i, result = 0;

  	for (i = 0; i < ARRAY_SIZE(info_readers); ++i) {

  		result = acpi_smbus_read(battery->sbs->hc,
  					 info_readers[i].mode,
  					 ACPI_SBS_BATTERY,
  					 info_readers[i].command,
  					 (u8 *) battery +
  						info_readers[i].offset);

  		if (result)
  			break;

  	}

  	return result;

  }

  static int acpi_battery_get_state(struct acpi_battery *battery)
  {

  	int i, result = 0;

  	if (battery->update_time &&
  	    time_before(jiffies, battery->update_time +

  				msecs_to_jiffies(cache_time)))
  		return 0;
  	for (i = 0; i < ARRAY_SIZE(state_readers); ++i) {
  		result = acpi_smbus_read(battery->sbs->hc,
  					 state_readers[i].mode,
  					 ACPI_SBS_BATTERY,
  					 state_readers[i].command,
  				         (u8 *)battery +
  						state_readers[i].offset);
  		if (result)

  			goto end;

  	}

        end:

  	battery->update_time = jiffies;

  	return result;

  }

  static int acpi_battery_get_alarm(struct acpi_battery *battery)

  {

  	return acpi_smbus_read(battery->sbs->hc, SMBUS_READ_WORD,
  				 ACPI_SBS_BATTERY, 0x01,

  				 (u8 *)&battery->alarm_capacity);

  }

  static int acpi_battery_set_alarm(struct acpi_battery *battery)

  {

  	struct acpi_sbs *sbs = battery->sbs;

  	u16 value, sel = 1 << (battery->id + 12);
  
  	int ret;

  	if (sbs->manager_present) {

  		ret = acpi_smbus_read(sbs->hc, SMBUS_READ_WORD, ACPI_SBS_MANAGER,

  				0x01, (u8 *)&value);

  		if (ret)
  			goto end;
  		if ((value & 0xf000) != sel) {
  			value &= 0x0fff;
  			value |= sel;
  		ret = acpi_smbus_write(sbs->hc, SMBUS_WRITE_WORD,
  					 ACPI_SBS_MANAGER,
  					 0x01, (u8 *)&value, 2);
  		if (ret)
  			goto end;
  		}

  	}

  	ret = acpi_smbus_write(sbs->hc, SMBUS_WRITE_WORD, ACPI_SBS_BATTERY,
  				0x01, (u8 *)&battery->alarm_capacity, 2);
        end:
  	return ret;

  }
  
  static int acpi_ac_get_present(struct acpi_sbs *sbs)
  {

  	int result;
  	u16 status;

  	result = acpi_smbus_read(sbs->hc, SMBUS_READ_WORD, ACPI_SBS_CHARGER,
  				 0x13, (u8 *) & status);
  	if (!result)
  		sbs->charger_present = (status >> 15) & 0x1;

  	return result;

  }

  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));
  	acpi_battery_get_alarm(battery);
  	return sprintf(buf, "%d
  ", battery->alarm_capacity *
  				acpi_battery_scale(battery) * 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_capacity = x /
  			(1000 * acpi_battery_scale(battery));
  	if (battery->present)
  		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,
  };

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

  #ifdef CONFIG_ACPI_PROCFS_POWER

  /* Generic Routines */

  static int

  acpi_sbs_add_fs(struct proc_dir_entry **dir,

  		struct proc_dir_entry *parent_dir,
  		char *dir_name,

  		const struct file_operations *info_fops,
  		const struct file_operations *state_fops,
  		const struct file_operations *alarm_fops, void *data)

  {

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

  	if (!*dir) {
  		*dir = proc_mkdir(dir_name, parent_dir);
  		if (!*dir) {

  			return -ENODEV;

  		}

  	}
  
  	/* 'info' [R] */

  	if (info_fops)
  		proc_create_data(ACPI_SBS_FILE_INFO, S_IRUGO, *dir,
  				 info_fops, data);

  
  	/* 'state' [R] */

  	if (state_fops)
  		proc_create_data(ACPI_SBS_FILE_STATE, S_IRUGO, *dir,
  				 state_fops, data);

  
  	/* 'alarm' [R/W] */

  	if (alarm_fops)
  		proc_create_data(ACPI_SBS_FILE_ALARM, S_IRUGO, *dir,
  				 alarm_fops, data);

  	return 0;

  }
  
  static void

  acpi_sbs_remove_fs(struct proc_dir_entry **dir,

  			   struct proc_dir_entry *parent_dir)
  {

  	if (*dir) {
  		remove_proc_entry(ACPI_SBS_FILE_INFO, *dir);
  		remove_proc_entry(ACPI_SBS_FILE_STATE, *dir);
  		remove_proc_entry(ACPI_SBS_FILE_ALARM, *dir);
  		remove_proc_entry((*dir)->name, parent_dir);
  		*dir = NULL;
  	}

  }
  
  /* Smart Battery Interface */

  static struct proc_dir_entry *acpi_battery_dir = NULL;

  static inline char *acpi_battery_units(struct acpi_battery *battery)
  {

  	return acpi_battery_mode(battery) ? " mW" : " mA";

  }

  static int acpi_battery_read_info(struct seq_file *seq, void *offset)
  {

  	struct acpi_battery *battery = seq->private;

  	struct acpi_sbs *sbs = battery->sbs;

  	int result = 0;

  	mutex_lock(&sbs->lock);

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

  		goto end;

  	seq_printf(seq, "design capacity:         %i%sh
  ",

  		   battery->design_capacity * acpi_battery_scale(battery),
  		   acpi_battery_units(battery));

  	seq_printf(seq, "last full capacity:      %i%sh
  ",

  		   battery->full_charge_capacity * acpi_battery_scale(battery),
  		   acpi_battery_units(battery));

  	seq_printf(seq, "battery technology:      rechargeable
  ");

  	seq_printf(seq, "design voltage:          %i mV
  ",

  		   battery->design_voltage * acpi_battery_vscale(battery));

  	seq_printf(seq, "design capacity warning: unknown
  ");
  	seq_printf(seq, "design capacity low:     unknown
  ");

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

  	seq_printf(seq, "capacity granularity 1:  unknown
  ");
  	seq_printf(seq, "capacity granularity 2:  unknown
  ");

  	seq_printf(seq, "model number:            %s
  ", battery->device_name);

  	seq_printf(seq, "serial number:           %i
  ",

  		   battery->serial_number);

  	seq_printf(seq, "battery type:            %s
  ",

  		   battery->device_chemistry);

  	seq_printf(seq, "OEM info:                %s
  ",

  		   battery->manufacturer_name);

        end:

  	mutex_unlock(&sbs->lock);

  	return result;

  }
  
  static int acpi_battery_info_open_fs(struct inode *inode, struct file *file)
  {
  	return single_open(file, acpi_battery_read_info, PDE(inode)->data);
  }
  
  static int acpi_battery_read_state(struct seq_file *seq, void *offset)
  {

  	struct acpi_battery *battery = seq->private;
  	struct acpi_sbs *sbs = battery->sbs;

  	int rate;

  	mutex_lock(&sbs->lock);
  	seq_printf(seq, "present:                 %s
  ",
  		   (battery->present) ? "yes" : "no");
  	if (!battery->present)

  		goto end;

  	acpi_battery_get_state(battery);
  	seq_printf(seq, "capacity state:          %s
  ",
  		   (battery->state & 0x0010) ? "critical" : "ok");
  	seq_printf(seq, "charging state:          %s
  ",

  		   (battery->rate_now < 0) ? "discharging" :
  		   ((battery->rate_now > 0) ? "charging" : "charged"));
  	rate = abs(battery->rate_now) * acpi_battery_ipscale(battery);

  	rate *= (acpi_battery_mode(battery))?(battery->voltage_now *
  			acpi_battery_vscale(battery)/1000):1;
  	seq_printf(seq, "present rate:            %d%s
  ", rate,
  		   acpi_battery_units(battery));
  	seq_printf(seq, "remaining capacity:      %i%sh
  ",

  		   battery->capacity_now * acpi_battery_scale(battery),
  		   acpi_battery_units(battery));

  	seq_printf(seq, "present voltage:         %i mV
  ",

  		   battery->voltage_now * acpi_battery_vscale(battery));

  
        end:

  	mutex_unlock(&sbs->lock);

  	return 0;

  }
  
  static int acpi_battery_state_open_fs(struct inode *inode, struct file *file)
  {
  	return single_open(file, acpi_battery_read_state, PDE(inode)->data);
  }
  
  static int acpi_battery_read_alarm(struct seq_file *seq, void *offset)
  {

  	struct acpi_battery *battery = seq->private;

  	struct acpi_sbs *sbs = battery->sbs;

  	int result = 0;

  	mutex_lock(&sbs->lock);

  	if (!battery->present) {

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

  	acpi_battery_get_alarm(battery);

  	seq_printf(seq, "alarm:                   ");

  	if (battery->alarm_capacity)

  		seq_printf(seq, "%i%sh
  ",

  			   battery->alarm_capacity *
  			   acpi_battery_scale(battery),
  			   acpi_battery_units(battery));
  	else

  		seq_printf(seq, "disabled
  ");

        end:

  	mutex_unlock(&sbs->lock);

  	return result;

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

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

  	struct acpi_sbs *sbs = battery->sbs;

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

  	int result = 0;
  	mutex_lock(&sbs->lock);

  	if (!battery->present) {

  		result = -ENODEV;
  		goto end;
  	}

  	if (count > sizeof(alarm_string) - 1) {
  		result = -EINVAL;
  		goto end;
  	}

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

  	alarm_string[count] = 0;

  	battery->alarm_capacity = simple_strtoul(alarm_string, NULL, 0) /
  					acpi_battery_scale(battery);

  	acpi_battery_set_alarm(battery);

        end:

  	mutex_unlock(&sbs->lock);
  	if (result)

  		return result;

  	return count;

  }
  
  static int acpi_battery_alarm_open_fs(struct inode *inode, struct file *file)
  {
  	return single_open(file, acpi_battery_read_alarm, PDE(inode)->data);
  }

  static const struct file_operations acpi_battery_info_fops = {

  	.open = acpi_battery_info_open_fs,
  	.read = seq_read,
  	.llseek = seq_lseek,
  	.release = single_release,
  	.owner = THIS_MODULE,
  };

  static const struct file_operations acpi_battery_state_fops = {

  	.open = acpi_battery_state_open_fs,
  	.read = seq_read,
  	.llseek = seq_lseek,
  	.release = single_release,
  	.owner = THIS_MODULE,
  };

  static const struct file_operations acpi_battery_alarm_fops = {

  	.open = acpi_battery_alarm_open_fs,
  	.read = seq_read,
  	.write = acpi_battery_write_alarm,
  	.llseek = seq_lseek,
  	.release = single_release,
  	.owner = THIS_MODULE,
  };
  
  /* Legacy AC Adapter Interface */
  
  static struct proc_dir_entry *acpi_ac_dir = NULL;
  
  static int acpi_ac_read_state(struct seq_file *seq, void *offset)
  {

  	struct acpi_sbs *sbs = seq->private;

  	mutex_lock(&sbs->lock);

  
  	seq_printf(seq, "state:                   %s
  ",

  		   sbs->charger_present ? "on-line" : "off-line");

  	mutex_unlock(&sbs->lock);

  	return 0;

  }
  
  static int acpi_ac_state_open_fs(struct inode *inode, struct file *file)
  {
  	return single_open(file, acpi_ac_read_state, PDE(inode)->data);
  }

  static const struct file_operations acpi_ac_state_fops = {

  	.open = acpi_ac_state_open_fs,
  	.read = seq_read,
  	.llseek = seq_lseek,
  	.release = single_release,
  	.owner = THIS_MODULE,
  };

  #endif

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

  static int acpi_battery_read(struct acpi_battery *battery)

  {

  	int result = 0, saved_present = battery->present;
  	u16 state;

  	if (battery->sbs->manager_present) {
  		result = acpi_smbus_read(battery->sbs->hc, SMBUS_READ_WORD,
  				ACPI_SBS_MANAGER, 0x01, (u8 *)&state);
  		if (!result)
  			battery->present = state & (1 << battery->id);
  		state &= 0x0fff;
  		state |= 1 << (battery->id + 12);
  		acpi_smbus_write(battery->sbs->hc, SMBUS_WRITE_WORD,
  				  ACPI_SBS_MANAGER, 0x01, (u8 *)&state, 2);
  	} else if (battery->id == 0)
  		battery->present = 1;
  	if (result || !battery->present)
  		return result;

  	if (saved_present != battery->present) {
  		battery->update_time = 0;
  		result = acpi_battery_get_info(battery);
  		if (result)
  			return result;
  	}
  	result = acpi_battery_get_state(battery);
  	return result;
  }

  /* Smart Battery */

  static int acpi_battery_add(struct acpi_sbs *sbs, int id)
  {

  	struct acpi_battery *battery = &sbs->battery[id];

  	int result;

  	battery->id = id;
  	battery->sbs = sbs;

  	result = acpi_battery_read(battery);
  	if (result)
  		return result;

  	sprintf(battery->name, ACPI_BATTERY_DIR_NAME, id);

  #ifdef CONFIG_ACPI_PROCFS_POWER

  	acpi_sbs_add_fs(&battery->proc_entry, acpi_battery_dir,
  			battery->name, &acpi_battery_info_fops,
  			&acpi_battery_state_fops, &acpi_battery_alarm_fops,
  			battery);

  #endif

  	battery->bat.name = battery->name;
  	battery->bat.type = POWER_SUPPLY_TYPE_BATTERY;
  	if (!acpi_battery_mode(battery)) {
  		battery->bat.properties = sbs_charge_battery_props;
  		battery->bat.num_properties =
  		    ARRAY_SIZE(sbs_charge_battery_props);
  	} else {
  		battery->bat.properties = sbs_energy_battery_props;
  		battery->bat.num_properties =
  		    ARRAY_SIZE(sbs_energy_battery_props);
  	}
  	battery->bat.get_property = acpi_sbs_battery_get_property;
  	result = power_supply_register(&sbs->device->dev, &battery->bat);

  	if (result)
  		goto end;
  	result = device_create_file(battery->bat.dev, &alarm_attr);
  	if (result)
  		goto end;
  	battery->have_sysfs_alarm = 1;
        end:

  	printk(KERN_INFO PREFIX "%s [%s]: Battery Slot [%s] (battery %s)
  ",

  	       ACPI_SBS_DEVICE_NAME, acpi_device_bid(sbs->device),

  	       battery->name, battery->present ? "present" : "absent");

  	return result;

  }
  
  static void acpi_battery_remove(struct acpi_sbs *sbs, int id)
  {

  	struct acpi_battery *battery = &sbs->battery[id];

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

  	}

  #ifdef CONFIG_ACPI_PROCFS_POWER

  	if (battery->proc_entry)
  		acpi_sbs_remove_fs(&battery->proc_entry, acpi_battery_dir);

  #endif

  }

  static int acpi_charger_add(struct acpi_sbs *sbs)

  {
  	int result;

  	result = acpi_ac_get_present(sbs);

  	if (result)

  		goto end;

  #ifdef CONFIG_ACPI_PROCFS_POWER

  	result = acpi_sbs_add_fs(&sbs->charger_entry, acpi_ac_dir,
  				 ACPI_AC_DIR_NAME, NULL,
  				 &acpi_ac_state_fops, NULL, sbs);
  	if (result)

  		goto end;

  #endif

  	sbs->charger.name = "sbs-charger";
  	sbs->charger.type = POWER_SUPPLY_TYPE_MAINS;
  	sbs->charger.properties = sbs_ac_props;
  	sbs->charger.num_properties = ARRAY_SIZE(sbs_ac_props);
  	sbs->charger.get_property = sbs_get_ac_property;
  	power_supply_register(&sbs->device->dev, &sbs->charger);

  	printk(KERN_INFO PREFIX "%s [%s]: AC Adapter [%s] (%s)
  ",
  	       ACPI_SBS_DEVICE_NAME, acpi_device_bid(sbs->device),

  	       ACPI_AC_DIR_NAME, sbs->charger_present ? "on-line" : "off-line");

        end:

  	return result;

  }

  static void acpi_charger_remove(struct acpi_sbs *sbs)

  {

  	if (sbs->charger.dev)
  		power_supply_unregister(&sbs->charger);

  #ifdef CONFIG_ACPI_PROCFS_POWER

  	if (sbs->charger_entry)
  		acpi_sbs_remove_fs(&sbs->charger_entry, acpi_ac_dir);

  #endif

  }

  static void acpi_sbs_callback(void *context)

  {

  	int id;
  	struct acpi_sbs *sbs = context;
  	struct acpi_battery *bat;
  	u8 saved_charger_state = sbs->charger_present;
  	u8 saved_battery_state;
  	acpi_ac_get_present(sbs);
  	if (sbs->charger_present != saved_charger_state) {

  #ifdef CONFIG_ACPI_PROC_EVENT

  		acpi_bus_generate_proc_event4(ACPI_AC_CLASS, ACPI_AC_DIR_NAME,
  					      ACPI_SBS_NOTIFY_STATUS,
  					      sbs->charger_present);

  #endif
  		kobject_uevent(&sbs->charger.dev->kobj, KOBJ_CHANGE);

  	}

  	if (sbs->manager_present) {
  		for (id = 0; id < MAX_SBS_BAT; ++id) {
  			if (!(sbs->batteries_supported & (1 << id)))
  				continue;
  			bat = &sbs->battery[id];
  			saved_battery_state = bat->present;
  			acpi_battery_read(bat);
  			if (saved_battery_state == bat->present)
  				continue;

  #ifdef CONFIG_ACPI_PROC_EVENT

  			acpi_bus_generate_proc_event4(ACPI_BATTERY_CLASS,
  						      bat->name,
  						      ACPI_SBS_NOTIFY_STATUS,
  						      bat->present);

  #endif
  			kobject_uevent(&bat->bat.dev->kobj, KOBJ_CHANGE);

  		}

  	}

  }

  static int acpi_sbs_add(struct acpi_device *device)
  {

  	struct acpi_sbs *sbs;
  	int result = 0;

  	int id;

  	sbs = kzalloc(sizeof(struct acpi_sbs), GFP_KERNEL);

  	if (!sbs) {

  		result = -ENOMEM;
  		goto end;

  	}

  	mutex_init(&sbs->lock);

  	sbs->hc = acpi_driver_data(device->parent);

  	sbs->device = device;

  	strcpy(acpi_device_name(device), ACPI_SBS_DEVICE_NAME);
  	strcpy(acpi_device_class(device), ACPI_SBS_CLASS);

  	device->driver_data = sbs;

  	result = acpi_charger_add(sbs);

  	if (result)
  		goto end;

  	result = acpi_manager_get_info(sbs);
  	if (!result) {
  		sbs->manager_present = 1;
  		for (id = 0; id < MAX_SBS_BAT; ++id)
  			if ((sbs->batteries_supported & (1 << id)))
  				acpi_battery_add(sbs, id);
  	} else
  		acpi_battery_add(sbs, 0);
  	acpi_smbus_register_callback(sbs->hc, acpi_sbs_callback, sbs);

        end:

  	if (result)
  		acpi_sbs_remove(device, 0);

  	return result;

  }

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

  {

  	struct acpi_sbs *sbs;

  	int id;

  	if (!device)

  		return -EINVAL;

  	sbs = acpi_driver_data(device);

  	if (!sbs)

  		return -EINVAL;

  	mutex_lock(&sbs->lock);
  	acpi_smbus_unregister_callback(sbs->hc);
  	for (id = 0; id < MAX_SBS_BAT; ++id)

  		acpi_battery_remove(sbs, id);

  	acpi_charger_remove(sbs);
  	mutex_unlock(&sbs->lock);
  	mutex_destroy(&sbs->lock);

  	kfree(sbs);

  	return 0;

  }

  static void acpi_sbs_rmdirs(void)
  {

  #ifdef CONFIG_ACPI_PROCFS_POWER

  	if (acpi_ac_dir) {
  		acpi_unlock_ac_dir(acpi_ac_dir);
  		acpi_ac_dir = NULL;
  	}
  	if (acpi_battery_dir) {
  		acpi_unlock_battery_dir(acpi_battery_dir);
  		acpi_battery_dir = NULL;
  	}

  #endif

  }
  
  static int acpi_sbs_resume(struct acpi_device *device)
  {
  	struct acpi_sbs *sbs;

  	if (!device)
  		return -EINVAL;

  	sbs = device->driver_data;

  	acpi_sbs_callback(sbs);

  	return 0;
  }

  static struct acpi_driver acpi_sbs_driver = {
  	.name = "sbs",
  	.class = ACPI_SBS_CLASS,
  	.ids = sbs_device_ids,
  	.ops = {
  		.add = acpi_sbs_add,
  		.remove = acpi_sbs_remove,
  		.resume = acpi_sbs_resume,
  		},
  };

  static int __init acpi_sbs_init(void)
  {
  	int result = 0;

  	if (acpi_disabled)
  		return -ENODEV;

  #ifdef CONFIG_ACPI_PROCFS_POWER

  	acpi_ac_dir = acpi_lock_ac_dir();

  	if (!acpi_ac_dir)

  		return -ENODEV;

  	acpi_battery_dir = acpi_lock_battery_dir();
  	if (!acpi_battery_dir) {

  		acpi_sbs_rmdirs();

  		return -ENODEV;

  	}

  #endif

  	result = acpi_bus_register_driver(&acpi_sbs_driver);
  	if (result < 0) {

  		acpi_sbs_rmdirs();

  		return -ENODEV;

  	}

  	return 0;

  }
  
  static void __exit acpi_sbs_exit(void)
  {

  	acpi_bus_unregister_driver(&acpi_sbs_driver);

  	acpi_sbs_rmdirs();

  	return;

  }
  
  module_init(acpi_sbs_init);
  module_exit(acpi_sbs_exit);