/*
* Copyright © 2007 Anton Vorontsov <cbou@mail.ru>
* Copyright © 2007 Eugeny Boger <eugenyboger@dgap.mipt.ru>
*
* Author: Eugeny Boger <eugenyboger@dgap.mipt.ru>
*
* Use consistent with the GNU GPL is permitted,
* provided that this copyright notice is
* preserved in its entirety in all copies and derived works.
*/
#include <linux/module.h>
#include <linux/power_supply.h>
#include <linux/apm-emulation.h>
#define PSY_PROP(psy, prop, val) psy->get_property(psy, \
POWER_SUPPLY_PROP_##prop, val)
#define _MPSY_PROP(prop, val) main_battery->get_property(main_battery, \
prop, val)
#define MPSY_PROP(prop, val) _MPSY_PROP(POWER_SUPPLY_PROP_##prop, val)
static struct power_supply *main_battery;
static void find_main_battery(void)
{
struct device *dev;
struct power_supply *bat, *batm;
union power_supply_propval full;
int max_charge = 0;
main_battery = NULL;
batm = NULL;
list_for_each_entry(dev, &power_supply_class->devices, node) {
bat = dev_get_drvdata(dev);
/* If none of battery devices cantains 'use_for_apm' flag,
choice one with maximum design charge */
if (!PSY_PROP(bat, CHARGE_FULL_DESIGN, &full)) {
if (full.intval > max_charge) {
batm = bat;
max_charge = full.intval;
}
}
if (bat->use_for_apm)
main_battery = bat;
}
if (!main_battery)
main_battery = batm;
}
static int calculate_time(int status)
{
union power_supply_propval charge_full, charge_empty;
union power_supply_propval charge, I;
if (MPSY_PROP(CHARGE_FULL, &charge_full)) {
/* if battery can't report this property, use design value */
if (MPSY_PROP(CHARGE_FULL_DESIGN, &charge_full))
return -1;
}
if (MPSY_PROP(CHARGE_EMPTY, &charge_empty)) {
/* if battery can't report this property, use design value */
if (MPSY_PROP(CHARGE_EMPTY_DESIGN, &charge_empty))
charge_empty.intval = 0;
}
if (MPSY_PROP(CHARGE_AVG, &charge)) {
/* if battery can't report average value, use momentary */
if (MPSY_PROP(CHARGE_NOW, &charge))
return -1;
}
if (MPSY_PROP(CURRENT_AVG, &I)) {
/* if battery can't report average value, use momentary */
if (MPSY_PROP(CURRENT_NOW, &I))
return -1;
}
if (status == POWER_SUPPLY_STATUS_CHARGING)
return ((charge.intval - charge_full.intval) * 60L) /
I.intval;
else
return -((charge.intval - charge_empty.intval) * 60L) /
I.intval;
}
static int calculate_capacity(int using_charge)
{
enum power_supply_property full_prop, empty_prop;
enum power_supply_property full_design_prop, empty_design_prop;
enum power_supply_property now_prop, avg_prop;
union power_supply_propval empty, full, cur;
int ret;
if (using_charge) {
full_prop = POWER_SUPPLY_PROP_CHARGE_FULL;
empty_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
full_design_prop = POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN;
empty_design_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN;
now_prop = POWER_SUPPLY_PROP_CHARGE_NOW;
avg_prop = POWER_SUPPLY_PROP_CHARGE_AVG;
} else {
full_prop = POWER_SUPPLY_PROP_ENERGY_FULL;
empty_prop = POWER_SUPPLY_PROP_ENERGY_EMPTY;
full_design_prop = POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN;
empty_design_prop = POWER_SUPPLY_PROP_ENERGY_EMPTY_DESIGN;
now_prop = POWER_SUPPLY_PROP_ENERGY_NOW;
avg_prop = POWER_SUPPLY_PROP_ENERGY_AVG;
}
if (_MPSY_PROP(full_prop, &full)) {
/* if battery can't report this property, use design value */
if (_MPSY_PROP(full_design_prop, &full))
return -1;
}
if (_MPSY_PROP(avg_prop, &cur)) {
/* if battery can't report average value, use momentary */
if (_MPSY_PROP(now_prop, &cur))
return -1;
}
if (_MPSY_PROP(empty_prop, &empty)) {
/* if battery can't report this property, use design value */
if (_MPSY_PROP(empty_design_prop, &empty))
empty.intval = 0;
}
if (full.intval - empty.intval)
ret = ((cur.intval - empty.intval) * 100L) /
(full.intval - empty.intval);
else
return -1;
if (ret > 100)
return 100;
else if (ret < 0)
return 0;
return ret;
}
static void apm_battery_apm_get_power_status(struct apm_power_info *info)
{
union power_supply_propval status;
union power_supply_propval capacity, time_to_full, time_to_empty;
down(&power_supply_class->sem);
find_main_battery();
if (!main_battery) {
up(&power_supply_class->sem);
return;
}
/* status */
if (MPSY_PROP(STATUS, &status))
status.intval = POWER_SUPPLY_STATUS_UNKNOWN;
/* ac line status */
if ((status.intval == POWER_SUPPLY_STATUS_CHARGING) ||
(status.intval == POWER_SUPPLY_STATUS_NOT_CHARGING) ||
(status.intval == POWER_SUPPLY_STATUS_FULL))
info->ac_line_status = APM_AC_ONLINE;
else
info->ac_line_status = APM_AC_OFFLINE;
/* battery life (i.e. capacity, in percents) */
if (MPSY_PROP(CAPACITY, &capacity) == 0) {
info->battery_life = capacity.intval;
} else {
/* try calculate using energy */
info->battery_life = calculate_capacity(0);
/* if failed try calculate using charge instead */
if (info->battery_life == -1)
info->battery_life = calculate_capacity(1);
}
/* charging status */
if (status.intval == POWER_SUPPLY_STATUS_CHARGING) {
info->battery_status = APM_BATTERY_STATUS_CHARGING;
} else {
if (info->battery_life > 50)
info->battery_status = APM_BATTERY_STATUS_HIGH;
else if (info->battery_life > 5)
info->battery_status = APM_BATTERY_STATUS_LOW;
else
info->battery_status = APM_BATTERY_STATUS_CRITICAL;
}
info->battery_flag = info->battery_status;
/* time */
info->units = APM_UNITS_MINS;
if (status.intval == POWER_SUPPLY_STATUS_CHARGING) {
if (!MPSY_PROP(TIME_TO_FULL_AVG, &time_to_full) ||
!MPSY_PROP(TIME_TO_FULL_NOW, &time_to_full))
info->time = time_to_full.intval / 60;
else
info->time = calculate_time(status.intval);
} else {
if (!MPSY_PROP(TIME_TO_EMPTY_AVG, &time_to_empty) ||
!MPSY_PROP(TIME_TO_EMPTY_NOW, &time_to_empty))
info->time = time_to_empty.intval / 60;
else
info->time = calculate_time(status.intval);
}
up(&power_supply_class->sem);
}
static int __init apm_battery_init(void)
{
printk(KERN_INFO "APM Battery Driver\n");
apm_get_power_status = apm_battery_apm_get_power_status;
return 0;
}
static void __exit apm_battery_exit(void)
{
apm_get_power_status = NULL;
}
module_init(apm_battery_init);
module_exit(apm_battery_exit);
MODULE_AUTHOR("Eugeny Boger <eugenyboger@dgap.mipt.ru>");
MODULE_DESCRIPTION("APM emulation driver for battery monitoring class");
MODULE_LICENSE("GPL");
