battery.c

linux 内核源代码

/*
 *  battery.c - ACPI Battery Driver (Revision: 2.0)
 *
 *  Copyright (C) 2007 Alexey Starikovskiy <[e-mail]>
 *  Copyright (C) 2004-2007 Vladimir Lebedev <[e-mail]>
 *  Copyright (C) 2001, 2002 Andy Grover <[e-mail]>
 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <[e-mail]>
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *  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>

#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>

#ifdef CONFIG_ACPI_SYSFS_POWER
#include <linux/power_supply.h>
#endif

#define ACPI_BATTERY_VALUE_UNKNOWN 0xFFFFFFFF

#define ACPI_BATTERY_COMPONENT		0x00040000
#define ACPI_BATTERY_CLASS		"battery"
#define ACPI_BATTERY_DEVICE_NAME	"Battery"
#define ACPI_BATTERY_NOTIFY_STATUS	0x80
#define ACPI_BATTERY_NOTIFY_INFO	0x81

#define _COMPONENT		ACPI_BATTERY_COMPONENT

ACPI_MODULE_NAME("battery");

MODULE_AUTHOR("Paul Diefenbaugh");
MODULE_AUTHOR("Alexey Starikovskiy <[e-mail]>");
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);


struct acpi_battery {
	struct mutex lock;
#ifdef CONFIG_ACPI_SYSFS_POWER
	struct power_supply bat;
#endif
	struct acpi_device *device;
	unsigned long update_time;
	int current_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 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;
	u8 alarm_present;
};

#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;
}

#ifdef CONFIG_ACPI_SYSFS_POWER
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_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 (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 (battery->state == 0)
			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_VOLTAGE_MIN_DESIGN:
		val->intval = battery->design_voltage * 1000;
		break;
	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
		val->intval = battery->voltage_now * 1000;
		break;
	case POWER_SUPPLY_PROP_CURRENT_NOW:
		val->intval = battery->current_now * 1000;
		break;
	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
		val->intval = battery->design_capacity * 1000;
		break;
	case POWER_SUPPLY_PROP_CHARGE_FULL:
	case POWER_SUPPLY_PROP_ENERGY_FULL:
		val->intval = battery->full_charge_capacity * 1000;
		break;
	case POWER_SUPPLY_PROP_CHARGE_NOW:
	case POWER_SUPPLY_PROP_ENERGY_NOW:
		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;
	default:
		return -EINVAL;
	}
	return 0;
}

static enum power_supply_property charge_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_CHARGE_FULL_DESIGN,
	POWER_SUPPLY_PROP_CHARGE_FULL,
	POWER_SUPPLY_PROP_CHARGE_NOW,
	POWER_SUPPLY_PROP_MODEL_NAME,
	POWER_SUPPLY_PROP_MANUFACTURER,
};

static enum power_supply_property 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_ENERGY_FULL_DESIGN,
	POWER_SUPPLY_PROP_ENERGY_FULL,
	POWER_SUPPLY_PROP_ENERGY_NOW,
	POWER_SUPPLY_PROP_MODEL_NAME,
	POWER_SUPPLY_PROP_MANUFACTURER,
};
#endif

#ifdef CONFIG_ACPI_PROCFS_POWER
inline char *acpi_battery_units(struct acpi_battery *battery)
{
	return (battery->power_unit)?"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, current_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 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(acpi_integer));
				ptr[sizeof(acpi_integer)] = 0;
			} else return -EFAULT;
		} else {
			if (element->type == ACPI_TYPE_INTEGER) {
				int *x = (int *)((u8 *)battery +
						offsets[i].offset);
				*x = element->integer.value;
			} else return -EFAULT;
		}
	}
	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;
	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, "_BIF",
				      NULL, &buffer);
	mutex_unlock(&battery->lock);

	if (ACPI_FAILURE(status)) {
		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BIF"));
		return -ENODEV;
	}

	result = extract_package(battery, buffer.pointer,
				 info_offsets, ARRAY_SIZE(info_offsets));
	kfree(buffer.pointer);
	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);
	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)|| !battery->alarm_present)
		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\n", 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)) {
		battery->alarm_present = 0;
		return 0;
	}
	battery->alarm_present = 1;
	if (!battery->alarm)
		battery->alarm = battery->design_capacity_warning;
	return acpi_battery_set_alarm(battery);
}

#ifdef CONFIG_ACPI_SYSFS_POWER
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\n", 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\n", &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, .owner = THIS_MODULE},
	.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) {
		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)