path: root/drivers/acpi/battery.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  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>
 */

#define pr_fmt(fmt) "ACPI: battery: " fmt

#include <linux/async.h>
#include <linux/delay.h>
#include <linux/dmi.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/suspend.h>
#include <linux/types.h>

#include <asm/unaligned.h>

#include <linux/acpi.h>
#include <linux/power_supply.h>

#include <acpi/battery.h>

#define ACPI_BATTERY_VALUE_UNKNOWN 0xFFFFFFFF
#define ACPI_BATTERY_CAPACITY_VALID(capacity) \
	((capacity) != 0 && (capacity) != ACPI_BATTERY_VALUE_UNKNOWN)

#define ACPI_BATTERY_DEVICE_NAME	"Battery"

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

#define ACPI_BATTERY_STATE_DISCHARGING	0x1
#define ACPI_BATTERY_STATE_CHARGING	0x2
#define ACPI_BATTERY_STATE_CRITICAL	0x4

MODULE_AUTHOR("Paul Diefenbaugh");
MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");
MODULE_DESCRIPTION("ACPI Battery Driver");
MODULE_LICENSE("GPL");

static async_cookie_t async_cookie;
static bool battery_driver_registered;
static int battery_bix_broken_package;
static int battery_notification_delay_ms;
static int battery_ac_is_broken;
static unsigned int cache_time = 1000;
module_param(cache_time, uint, 0644);
MODULE_PARM_DESC(cache_time, "cache time in milliseconds");

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

	/* Microsoft Surface Go 3 */
	{"MSHW0146", 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,
	/* for batteries reporting current capacity with design capacity
	 * on a full charge, but showing degradation in full charge cap.
	 */
	ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE,
};

struct acpi_battery {
	struct mutex lock;
	struct mutex sysfs_lock;
	struct power_supply *bat;
	struct power_supply_desc bat_desc;
	struct acpi_device *device;
	struct notifier_block pm_nb;
	struct list_head list;
	unsigned long update_time;
	int revision;
	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) power_supply_get_drvdata(x)

static 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->t