298 lines
7.0 KiB
C
298 lines
7.0 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* Battery driver for Acer Iconia Tab A500.
|
|
*
|
|
* Copyright 2020 GRATE-driver project.
|
|
*
|
|
* Based on downstream driver from Acer Inc.
|
|
* Based on NVIDIA Gas Gauge driver for SBS Compliant Batteries.
|
|
*
|
|
* Copyright (c) 2010, NVIDIA Corporation.
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/power_supply.h>
|
|
#include <linux/regmap.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/workqueue.h>
|
|
|
|
enum {
|
|
REG_CAPACITY,
|
|
REG_VOLTAGE,
|
|
REG_CURRENT,
|
|
REG_DESIGN_CAPACITY,
|
|
REG_TEMPERATURE,
|
|
};
|
|
|
|
#define EC_DATA(_reg, _psp) { \
|
|
.psp = POWER_SUPPLY_PROP_ ## _psp, \
|
|
.reg = _reg, \
|
|
}
|
|
|
|
static const struct battery_register {
|
|
enum power_supply_property psp;
|
|
unsigned int reg;
|
|
} ec_data[] = {
|
|
[REG_CAPACITY] = EC_DATA(0x00, CAPACITY),
|
|
[REG_VOLTAGE] = EC_DATA(0x01, VOLTAGE_NOW),
|
|
[REG_CURRENT] = EC_DATA(0x03, CURRENT_NOW),
|
|
[REG_DESIGN_CAPACITY] = EC_DATA(0x08, CHARGE_FULL_DESIGN),
|
|
[REG_TEMPERATURE] = EC_DATA(0x0a, TEMP),
|
|
};
|
|
|
|
static const enum power_supply_property a500_battery_properties[] = {
|
|
POWER_SUPPLY_PROP_CAPACITY,
|
|
POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
|
|
POWER_SUPPLY_PROP_CURRENT_NOW,
|
|
POWER_SUPPLY_PROP_PRESENT,
|
|
POWER_SUPPLY_PROP_STATUS,
|
|
POWER_SUPPLY_PROP_TECHNOLOGY,
|
|
POWER_SUPPLY_PROP_TEMP,
|
|
POWER_SUPPLY_PROP_VOLTAGE_NOW,
|
|
};
|
|
|
|
struct a500_battery {
|
|
struct delayed_work poll_work;
|
|
struct power_supply *psy;
|
|
struct regmap *regmap;
|
|
unsigned int capacity;
|
|
};
|
|
|
|
static bool a500_battery_update_capacity(struct a500_battery *bat)
|
|
{
|
|
unsigned int capacity;
|
|
int err;
|
|
|
|
err = regmap_read(bat->regmap, ec_data[REG_CAPACITY].reg, &capacity);
|
|
if (err)
|
|
return false;
|
|
|
|
/* capacity can be >100% even if max value is 100% */
|
|
capacity = min(capacity, 100u);
|
|
|
|
if (bat->capacity != capacity) {
|
|
bat->capacity = capacity;
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
static int a500_battery_get_status(struct a500_battery *bat)
|
|
{
|
|
if (bat->capacity < 100) {
|
|
if (power_supply_am_i_supplied(bat->psy))
|
|
return POWER_SUPPLY_STATUS_CHARGING;
|
|
else
|
|
return POWER_SUPPLY_STATUS_DISCHARGING;
|
|
}
|
|
|
|
return POWER_SUPPLY_STATUS_FULL;
|
|
}
|
|
|
|
static void a500_battery_unit_adjustment(struct device *dev,
|
|
enum power_supply_property psp,
|
|
union power_supply_propval *val)
|
|
{
|
|
const unsigned int base_unit_conversion = 1000;
|
|
const unsigned int temp_kelvin_to_celsius = 2731;
|
|
|
|
switch (psp) {
|
|
case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
|
|
case POWER_SUPPLY_PROP_CURRENT_NOW:
|
|
case POWER_SUPPLY_PROP_VOLTAGE_NOW:
|
|
val->intval *= base_unit_conversion;
|
|
break;
|
|
|
|
case POWER_SUPPLY_PROP_TEMP:
|
|
val->intval -= temp_kelvin_to_celsius;
|
|
break;
|
|
|
|
case POWER_SUPPLY_PROP_PRESENT:
|
|
val->intval = !!val->intval;
|
|
break;
|
|
|
|
default:
|
|
dev_dbg(dev,
|
|
"%s: no need for unit conversion %d\n", __func__, psp);
|
|
}
|
|
}
|
|
|
|
static int a500_battery_get_ec_data_index(struct device *dev,
|
|
enum power_supply_property psp)
|
|
{
|
|
unsigned int i;
|
|
|
|
/*
|
|
* DESIGN_CAPACITY register always returns a non-zero value if
|
|
* battery is connected and zero if disconnected, hence we'll use
|
|
* it for judging the battery presence.
|
|
*/
|
|
if (psp == POWER_SUPPLY_PROP_PRESENT)
|
|
psp = POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(ec_data); i++)
|
|
if (psp == ec_data[i].psp)
|
|
return i;
|
|
|
|
dev_dbg(dev, "%s: invalid property %u\n", __func__, psp);
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
static int a500_battery_get_property(struct power_supply *psy,
|
|
enum power_supply_property psp,
|
|
union power_supply_propval *val)
|
|
{
|
|
struct a500_battery *bat = power_supply_get_drvdata(psy);
|
|
struct device *dev = psy->dev.parent;
|
|
int ret = 0;
|
|
|
|
switch (psp) {
|
|
case POWER_SUPPLY_PROP_STATUS:
|
|
val->intval = a500_battery_get_status(bat);
|
|
break;
|
|
|
|
case POWER_SUPPLY_PROP_TECHNOLOGY:
|
|
val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
|
|
break;
|
|
|
|
case POWER_SUPPLY_PROP_CAPACITY:
|
|
a500_battery_update_capacity(bat);
|
|
val->intval = bat->capacity;
|
|
break;
|
|
|
|
case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
|
|
case POWER_SUPPLY_PROP_CURRENT_NOW:
|
|
case POWER_SUPPLY_PROP_VOLTAGE_NOW:
|
|
case POWER_SUPPLY_PROP_PRESENT:
|
|
case POWER_SUPPLY_PROP_TEMP:
|
|
ret = a500_battery_get_ec_data_index(dev, psp);
|
|
if (ret < 0)
|
|
break;
|
|
|
|
ret = regmap_read(bat->regmap, ec_data[ret].reg, &val->intval);
|
|
break;
|
|
|
|
default:
|
|
dev_err(dev, "%s: invalid property %u\n", __func__, psp);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!ret) {
|
|
/* convert units to match requirements of power supply class */
|
|
a500_battery_unit_adjustment(dev, psp, val);
|
|
}
|
|
|
|
dev_dbg(dev, "%s: property = %d, value = %x\n",
|
|
__func__, psp, val->intval);
|
|
|
|
/* return NODATA for properties if battery not presents */
|
|
if (ret)
|
|
return -ENODATA;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void a500_battery_poll_work(struct work_struct *work)
|
|
{
|
|
struct a500_battery *bat;
|
|
bool capacity_changed;
|
|
|
|
bat = container_of(work, struct a500_battery, poll_work.work);
|
|
capacity_changed = a500_battery_update_capacity(bat);
|
|
|
|
if (capacity_changed)
|
|
power_supply_changed(bat->psy);
|
|
|
|
/* continuously send uevent notification */
|
|
schedule_delayed_work(&bat->poll_work, 30 * HZ);
|
|
}
|
|
|
|
static const struct power_supply_desc a500_battery_desc = {
|
|
.name = "ec-battery",
|
|
.type = POWER_SUPPLY_TYPE_BATTERY,
|
|
.properties = a500_battery_properties,
|
|
.get_property = a500_battery_get_property,
|
|
.num_properties = ARRAY_SIZE(a500_battery_properties),
|
|
.external_power_changed = power_supply_changed,
|
|
};
|
|
|
|
static int a500_battery_probe(struct platform_device *pdev)
|
|
{
|
|
struct power_supply_config psy_cfg = {};
|
|
struct a500_battery *bat;
|
|
|
|
bat = devm_kzalloc(&pdev->dev, sizeof(*bat), GFP_KERNEL);
|
|
if (!bat)
|
|
return -ENOMEM;
|
|
|
|
platform_set_drvdata(pdev, bat);
|
|
|
|
psy_cfg.of_node = pdev->dev.parent->of_node;
|
|
psy_cfg.drv_data = bat;
|
|
|
|
bat->regmap = dev_get_regmap(pdev->dev.parent, "KB930");
|
|
if (!bat->regmap)
|
|
return -EINVAL;
|
|
|
|
bat->psy = devm_power_supply_register_no_ws(&pdev->dev,
|
|
&a500_battery_desc,
|
|
&psy_cfg);
|
|
if (IS_ERR(bat->psy))
|
|
return dev_err_probe(&pdev->dev, PTR_ERR(bat->psy),
|
|
"failed to register battery\n");
|
|
|
|
INIT_DELAYED_WORK(&bat->poll_work, a500_battery_poll_work);
|
|
schedule_delayed_work(&bat->poll_work, HZ);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int a500_battery_remove(struct platform_device *pdev)
|
|
{
|
|
struct a500_battery *bat = dev_get_drvdata(&pdev->dev);
|
|
|
|
cancel_delayed_work_sync(&bat->poll_work);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __maybe_unused a500_battery_suspend(struct device *dev)
|
|
{
|
|
struct a500_battery *bat = dev_get_drvdata(dev);
|
|
|
|
cancel_delayed_work_sync(&bat->poll_work);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __maybe_unused a500_battery_resume(struct device *dev)
|
|
{
|
|
struct a500_battery *bat = dev_get_drvdata(dev);
|
|
|
|
schedule_delayed_work(&bat->poll_work, HZ);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static SIMPLE_DEV_PM_OPS(a500_battery_pm_ops,
|
|
a500_battery_suspend, a500_battery_resume);
|
|
|
|
static struct platform_driver a500_battery_driver = {
|
|
.driver = {
|
|
.name = "acer-a500-iconia-battery",
|
|
.pm = &a500_battery_pm_ops,
|
|
},
|
|
.probe = a500_battery_probe,
|
|
.remove = a500_battery_remove,
|
|
};
|
|
module_platform_driver(a500_battery_driver);
|
|
|
|
MODULE_DESCRIPTION("Battery gauge driver for Acer Iconia Tab A500");
|
|
MODULE_AUTHOR("Dmitry Osipenko <digetx@gmail.com>");
|
|
MODULE_ALIAS("platform:acer-a500-iconia-battery");
|
|
MODULE_LICENSE("GPL");
|