/*
* Battery measurement code for Zipit Z2
*
* Copyright (C) 2009 Peter Edwards <sweetlilmre@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/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/i2c.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/gpio.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <asm/irq.h>
#include <asm/mach/irq.h>
#include <linux/z2_battery.h>
#define Z2_DEFAULT_NAME "Z2"
struct z2_charger {
struct z2_battery_info *info;
int bat_status;
struct i2c_client *client;
struct power_supply batt_ps;
struct mutex work_lock;
struct work_struct bat_work;
};
static unsigned long z2_read_bat(struct z2_charger *charger)
{
int data;
data = i2c_smbus_read_byte_data(charger->client,
charger->info->batt_I2C_reg);
if (data < 0)
return 0;
return data * charger->info->batt_mult / charger->info->batt_div;
}
static int z2_batt_get_property(struct power_supply *batt_ps,
enum power_supply_property psp,
union power_supply_propval *val)
{
struct z2_charger *charger = container_of(batt_ps, struct z2_charger,
batt_ps);
struct z2_battery_info *info = charger->info;
switch (psp) {
case POWER_SUPPLY_PROP_STATUS:
val->intval = charger->bat_status;
break;
case POWER_SUPPLY_PROP_TECHNOLOGY:
val->intval = info->batt_tech;
break;
case POWER_SUPPLY_PROP_VOLTAGE_NOW:
if (info->batt_I2C_reg >= 0)
val->intval = z2_read_bat(charger);
else
return -EINVAL;
break;
case POWER_SUPPLY_PROP_VOLTAGE_MAX:
if (info->max_voltage >= 0)
val->intval = info->max_voltage;
else
return -EINVAL;
break;
case POWER_SUPPLY_PROP_VOLTAGE_MIN:
if (info->min_voltage >= 0)
val->intval = info->min_voltage;
else
return -EINVAL;
break;
case POWER_SUPPLY_PROP_PRESENT:
val->intval = 1;
break;
default:
return -EINVAL;
}
return 0;
}
static void z2_batt_ext_power_changed(struct power_supply *batt_ps)
{
struct z2_charger *charger = container_of(batt_ps, struct z2_charger,
batt_ps);
schedule_work(&charger->bat_work);
}
static void z2_batt_update(struct z2_charger *charger)
{
int old_status = charger->bat_status;
struct z2_battery_info *info;
info = charger->info;
mutex_lock(&charger->work_lock);
charger->bat_status = (info->charge_gpio >= 0) ?
(gpio_get_value(info->charge_gpio) ?
POWER_SUPPLY_STATUS_CHARGING :
POWER_SUPPLY_STATUS_DISCHARGING) :
POWER_SUPPLY_STATUS_UNKNOWN;
if (old_status != charger->bat_status) {
pr_debug("%s: %i -> %i\n", charger->batt_ps.name, old_status,
charger->bat_status);
power_supply_changed(&charger->batt_ps);
}
mutex_unlock(&charger->work_lock);
}
static void z2_batt_work(struct work_struct *work)
{
struct z2_charger *charger;
charger = container_of(work, struct z2_charger, bat_work);
z2_batt_update(charger);
}
static irqreturn_t z2_charge_switch_irq(int irq, void *devid)
{
struct z2_charger *charger = devid;
schedule_work(&charger->bat_work);
return IRQ_HANDLED;
}
static int z2_batt_ps_init(struct z2_charger *charger, int props)
{
int i = 0;
enum power_supply_property *prop;
struct z2_battery_info *info = charger->info;
if (info->batt_tech >= 0)
props++; /* POWER_SUPPLY_PROP_TECHNOLOGY */
if (info->batt_I2C_reg >= 0)
props++; /* POWER_SUPPLY_PROP_VOLTAGE_NOW */
if (info->max_voltage >= 0)
props++; /* POWER_SUPPLY_PROP_VOLTAGE_MAX */
if (info->min_voltage >= 0)
props++; /* POWER_SUPPLY_PROP_VOLTAGE_MIN */
prop = kzalloc(props * sizeof(*prop), GFP_KERNEL);
if (!prop)
return -ENOMEM;
prop[i++] = POWER_SUPPLY_PROP_PRESENT;
if (info->charge_gpio >= 0)
prop[i++] = POWER_SUPPLY_PROP_STATUS;
if (info->batt_tech >= 0)
prop[i++] = POWER_SUPPLY_PROP_TECHNOLOGY;
if (info->batt_I2C_reg >= 0)
prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_NOW;
if (info->max_voltage >= 0)
prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MAX;
if (info->min_voltage >= 0)
prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MIN;
if (!info->batt_name) {
dev_info(&charger->client->dev,
"Please consider setting proper battery "
"name in platform definition file, falling "
"back to name \" Z2_DEFAULT_NAME \"\n");
charger->batt_ps.name = Z2_DEFAULT_NAME;
} else
charger->batt_ps.name = info->batt_name;
charger->batt_ps.properties = prop;
charger->batt_ps.num_properties = props;
charger->batt_ps.type = POWER_SUPPLY_TYPE_BATTERY;
charger->batt_ps.get_property = z2_batt_get_property;
charger->batt_ps.external_power_changed = z2_batt_ext_power_changed;
charger->batt_ps.use_for_apm = 1;
return 0;
}
static int __devinit z2_batt_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
int ret = 0;
int props = 1; /* POWER_SUPPLY_PROP_PRESENT */
struct z2_charger *charger;
struct z2_battery_info *info = client->dev.platform_data;
if (info == NULL) {
dev_err(&client->dev,
"Please set platform device platform_data"
" to a valid z2_battery_info pointer!\n");
return -EINVAL;
}
charger = kzalloc(sizeof(*charger), GFP_KERNEL);
if (charger == NULL)
return -ENOMEM;
charger->bat_status = POWER_SUPPLY_STATUS_UNKNOWN;
charger->info = info;
charger->client = client;
i2c_set_clientdata(client, charger);
mutex_init(&charger->work_lock);
if (info->charge_gpio >= 0 && gpio_is_valid(info->charge_gpio)) {
ret = gpio_request(info->charge_gpio, "BATT CHRG");
if (ret)
goto err;
ret = gpio_direction_input(info->charge_gpio);
if (ret)
goto err2;
set_irq_type(gpio_to_irq(info->charge_gpio),
IRQ_TYPE_EDGE_BOTH);
ret = request_irq(gpio_to_irq(info->charge_gpio),
z2_charge_switch_irq, IRQF_DISABLED,
"AC Detect", charger);
if (ret)
goto err3;
}
ret = z2_batt_ps_init(charger, props);
if (ret)
goto err3;
INIT_WORK(&charger->bat_work, z2_batt_work);
ret = power_supply_register(&client->dev, &charger->batt_ps);
if (ret)
goto err4;
schedule_work(&charger->bat_work);
return 0;
err4:
kfree(charger->batt_ps.properties);
err3:
if (info->charge_gpio >= 0 && gpio_is_valid(info->charge_gpio))
free_irq(gpio_to_irq(info->charge_gpio), charger);
err2:
if (info->charge_gpio >= 0 && gpio_is_valid(info->charge_gpio))
gpio_free(info->charge_gpio);
err:
kfree(charger);
return ret;
}
static int __devexit z2_batt_remove(struct i2c_client *client)
{
struct z2_charger *charger = i2c_get_clientdata(client);
struct z2_battery_info *info = charger->info;
flush_scheduled_work();
power_supply_unregister(&charger->batt_ps);
kfree(charger->batt_ps.properties);
if (info->charge_gpio >= 0 && gpio_is_valid(info->charge_gpio)) {
free_irq(gpio_to_irq(info->charge_gpio), charger);
gpio_free(info->charge_gpio);
}
kfree(charger);
return 0;
}
#ifdef CONFIG_PM
static int z2_batt_suspend(struct i2c_client *client, pm_message_t state)
{
flush_scheduled_work();
return 0;
}
static int z2_batt_resume(struct i2c_client *client)
{
struct z2_charger *charger = i2c_get_clientdata(client);
schedule_work(&charger->bat_work);
return 0;
}
#else
#define z2_batt_suspend NULL
#define z2_batt_resume NULL
#endif
static const struct i2c_device_id z2_batt_id[] = {
{ "aer915", 0 },
{ }
};
static struct i2c_driver z2_batt_driver = {
.driver = {
.name = "z2-battery",
.owner = THIS_MODULE,
},
.probe = z2_batt_probe,
.remove = z2_batt_remove,
.suspend = z2_batt_suspend,
.resume = z2_batt_resume,
.id_table = z2_batt_id,
};
static int __init z2_batt_init(void)
{
return i2c_add_driver(&z2_batt_driver);
}
static void __exit z2_batt_exit(void)
{
i2c_del_driver(&z2_batt_driver);
}
module_init(z2_batt_init);
module_exit(z2_batt_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Peter Edwards <sweetlilmre@gmail.com>");
MODULE_DESCRIPTION("Zipit Z2 battery driver");
