path: root/drivers/acpi/battery.c

/*
 *  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>
#include <asm/unaligned.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,
	/* On Lenovo Thinkpad models from 2010 and 2011, the power unit
	   switches between mWh and mAh depending on whether the system
	   is running on battery or not.  When mAh is the unit, most
	   reported values are incorrect and need to be adjusted by
	   10000/design_voltage.  Verified on x201, t410, t410s, and x220.
	   Pre-2010 and 2012 models appear to always report in mWh and
	   are thus unaffected (tested with t42, t61, t500, x200, x300,
	   and x230).  Also, in mid-2012 Lenovo issued a BIOS update for
	   the 2011 models that fixes the issue (tested on x220 with a
	   post-1.29 BIOS), but as of Nov. 2012, no such update is
	   available for the 2010 models.  */
	ACPI_BATTERY_QUIRK_THINKPAD_MAH,
};

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)

static inline int acpi_battery_present(struct acpi_battery *battery)
{
	return battery->device->status.battery_present;
}

static int acpi_battery_technology(struct acpi