linux/drivers/power/palmtx_battery.c

199 lines
4.6 KiB
C

/*
* linux/drivers/power/palmtx_battery.c
*
* Battery measurement code for Palm T|X Handheld computer
*
* based on tosa_battery.c
*
* Copyright (C) 2008 Marek Vasut <marek.vasut@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/power_supply.h>
#include <linux/wm97xx.h>
#include <linux/delay.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/gpio.h>
#include <asm/mach-types.h>
#include <asm/arch/palmtx.h>
static DEFINE_MUTEX(bat_lock);
static struct work_struct bat_work;
struct mutex work_lock;
int bat_status = POWER_SUPPLY_STATUS_DISCHARGING;
static unsigned long palmtx_read_bat(struct power_supply *bat_ps)
{
return wm97xx_read_aux_adc(bat_ps->dev->parent->driver_data,
WM97XX_AUX_ID3) * 1000 / 414;
}
static unsigned long palmtx_read_temp(struct power_supply *bat_ps)
{
return wm97xx_read_aux_adc(bat_ps->dev->parent->driver_data,
WM97XX_AUX_ID2);
}
static int palmtx_bat_get_property(struct power_supply *bat_ps,
enum power_supply_property psp,
union power_supply_propval *val)
{
switch (psp) {
case POWER_SUPPLY_PROP_STATUS:
val->intval = bat_status;
break;
case POWER_SUPPLY_PROP_TECHNOLOGY:
val->intval = POWER_SUPPLY_TECHNOLOGY_LIPO;
break;
case POWER_SUPPLY_PROP_VOLTAGE_NOW:
val->intval = palmtx_read_bat(bat_ps);
break;
case POWER_SUPPLY_PROP_VOLTAGE_MAX:
case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
val->intval = PALMTX_BAT_MAX_VOLTAGE;
break;
case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
val->intval = PALMTX_BAT_MIN_VOLTAGE;
break;
case POWER_SUPPLY_PROP_TEMP:
val->intval = palmtx_read_temp(bat_ps);
break;
case POWER_SUPPLY_PROP_PRESENT:
val->intval = 1;
break;
default:
return -EINVAL;
}
return 0;
}
static void palmtx_bat_external_power_changed(struct power_supply *bat_ps)
{
schedule_work(&bat_work);
}
static char *status_text[] = {
[POWER_SUPPLY_STATUS_UNKNOWN] = "Unknown",
[POWER_SUPPLY_STATUS_CHARGING] = "Charging",
[POWER_SUPPLY_STATUS_DISCHARGING] = "Discharging",
};
static void palmtx_bat_update(struct power_supply *bat_ps)
{
int old_status = bat_status;
mutex_lock(&work_lock);
bat_status = gpio_get_value(GPIO_NR_PALMTX_POWER_DETECT) ?
POWER_SUPPLY_STATUS_CHARGING :
POWER_SUPPLY_STATUS_DISCHARGING;
if (old_status != bat_status) {
pr_debug("%s %s -> %s\n", bat_ps->name,
status_text[old_status],
status_text[bat_status]);
power_supply_changed(bat_ps);
}
mutex_unlock(&work_lock);
}
static enum power_supply_property palmtx_bat_main_props[] = {
POWER_SUPPLY_PROP_STATUS,
POWER_SUPPLY_PROP_TECHNOLOGY,
POWER_SUPPLY_PROP_VOLTAGE_NOW,
POWER_SUPPLY_PROP_VOLTAGE_MAX,
POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
POWER_SUPPLY_PROP_TEMP,
POWER_SUPPLY_PROP_PRESENT,
};
struct power_supply bat_ps = {
.name = "main-battery",
.type = POWER_SUPPLY_TYPE_BATTERY,
.properties = palmtx_bat_main_props,
.num_properties = ARRAY_SIZE(palmtx_bat_main_props),
.get_property = palmtx_bat_get_property,
.external_power_changed = palmtx_bat_external_power_changed,
.use_for_apm = 1,
};
static void palmtx_bat_work(struct work_struct *work)
{
palmtx_bat_update(&bat_ps);
}
#ifdef CONFIG_PM
static int palmtx_bat_suspend(struct platform_device *dev, pm_message_t state)
{
flush_scheduled_work();
return 0;
}
static int palmtx_bat_resume(struct platform_device *dev)
{
schedule_work(&bat_work);
return 0;
}
#else
#define palmtx_bat_suspend NULL
#define palmtx_bat_resume NULL
#endif
static int __devinit palmtx_bat_probe(struct platform_device *dev)
{
int ret = 0;
if (!machine_is_palmtx())
return -ENODEV;
mutex_init(&work_lock);
INIT_WORK(&bat_work, palmtx_bat_work);
ret = power_supply_register(&dev->dev, &bat_ps);
if (!ret)
schedule_work(&bat_work);
return ret;
}
static int __devexit palmtx_bat_remove(struct platform_device *dev)
{
power_supply_unregister(&bat_ps);
return 0;
}
static struct platform_driver palmtx_bat_driver = {
.driver.name = "wm97xx-battery",
.driver.owner = THIS_MODULE,
.probe = palmtx_bat_probe,
.remove = __devexit_p(palmtx_bat_remove),
.suspend = palmtx_bat_suspend,
.resume = palmtx_bat_resume,
};
static int __init palmtx_bat_init(void)
{
return platform_driver_register(&palmtx_bat_driver);
}
static void __exit palmtx_bat_exit(void)
{
platform_driver_unregister(&palmtx_bat_driver);
}
module_init(palmtx_bat_init);
module_exit(palmtx_bat_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
MODULE_DESCRIPTION("Palm T|X battery driver");