linux/drivers/power/bq20z75.c
Rhyland Klein d3ab61ecba bq20z75: Add support for more power supply properties
This patch adds properties to support devicekit power. Also, create IO
wrapper functions and fix some issues found while testing, including
unit conversions to match the power_supply types.

Signed-off-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
2010-09-28 16:42:35 +04:00

494 lines
12 KiB
C

/*
* Gas Gauge driver for TI's BQ20Z75
*
* Copyright (c) 2010, NVIDIA Corporation.
*
* 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.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/power_supply.h>
#include <linux/i2c.h>
#include <linux/slab.h>
enum {
REG_MANUFACTURER_DATA,
REG_TEMPERATURE,
REG_VOLTAGE,
REG_CURRENT,
REG_CAPACITY,
REG_TIME_TO_EMPTY,
REG_TIME_TO_FULL,
REG_STATUS,
REG_CYCLE_COUNT,
REG_SERIAL_NUMBER,
REG_REMAINING_CAPACITY,
REG_FULL_CHARGE_CAPACITY,
REG_DESIGN_CAPACITY,
REG_DESIGN_VOLTAGE,
};
/* manufacturer access defines */
#define MANUFACTURER_ACCESS_STATUS 0x0006
#define MANUFACTURER_ACCESS_SLEEP 0x0011
/* battery status value bits */
#define BATTERY_DISCHARGING 0x40
#define BATTERY_FULL_CHARGED 0x20
#define BATTERY_FULL_DISCHARGED 0x10
#define BQ20Z75_DATA(_psp, _addr, _min_value, _max_value) { \
.psp = _psp, \
.addr = _addr, \
.min_value = _min_value, \
.max_value = _max_value, \
}
static const struct bq20z75_device_data {
enum power_supply_property psp;
u8 addr;
int min_value;
int max_value;
} bq20z75_data[] = {
[REG_MANUFACTURER_DATA] =
BQ20Z75_DATA(POWER_SUPPLY_PROP_PRESENT, 0x00, 0, 65535),
[REG_TEMPERATURE] =
BQ20Z75_DATA(POWER_SUPPLY_PROP_TEMP, 0x08, 0, 65535),
[REG_VOLTAGE] =
BQ20Z75_DATA(POWER_SUPPLY_PROP_VOLTAGE_NOW, 0x09, 0, 20000),
[REG_CURRENT] =
BQ20Z75_DATA(POWER_SUPPLY_PROP_CURRENT_NOW, 0x0A, -32768,
32767),
[REG_CAPACITY] =
BQ20Z75_DATA(POWER_SUPPLY_PROP_CAPACITY, 0x0E, 0, 100),
[REG_REMAINING_CAPACITY] =
BQ20Z75_DATA(POWER_SUPPLY_PROP_ENERGY_NOW, 0x0F, 0, 65535),
[REG_FULL_CHARGE_CAPACITY] =
BQ20Z75_DATA(POWER_SUPPLY_PROP_ENERGY_FULL, 0x10, 0, 65535),
[REG_TIME_TO_EMPTY] =
BQ20Z75_DATA(POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG, 0x12, 0,
65535),
[REG_TIME_TO_FULL] =
BQ20Z75_DATA(POWER_SUPPLY_PROP_TIME_TO_FULL_AVG, 0x13, 0,
65535),
[REG_STATUS] =
BQ20Z75_DATA(POWER_SUPPLY_PROP_STATUS, 0x16, 0, 65535),
[REG_CYCLE_COUNT] =
BQ20Z75_DATA(POWER_SUPPLY_PROP_CYCLE_COUNT, 0x17, 0, 65535),
[REG_DESIGN_CAPACITY] =
BQ20Z75_DATA(POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN, 0x18, 0,
65535),
[REG_DESIGN_VOLTAGE] =
BQ20Z75_DATA(POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN, 0x19, 0,
65535),
[REG_SERIAL_NUMBER] =
BQ20Z75_DATA(POWER_SUPPLY_PROP_SERIAL_NUMBER, 0x1C, 0, 65535),
};
static enum power_supply_property bq20z75_properties[] = {
POWER_SUPPLY_PROP_STATUS,
POWER_SUPPLY_PROP_HEALTH,
POWER_SUPPLY_PROP_PRESENT,
POWER_SUPPLY_PROP_TECHNOLOGY,
POWER_SUPPLY_PROP_CYCLE_COUNT,
POWER_SUPPLY_PROP_VOLTAGE_NOW,
POWER_SUPPLY_PROP_CURRENT_NOW,
POWER_SUPPLY_PROP_CAPACITY,
POWER_SUPPLY_PROP_TEMP,
POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
POWER_SUPPLY_PROP_TIME_TO_FULL_AVG,
POWER_SUPPLY_PROP_SERIAL_NUMBER,
POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
POWER_SUPPLY_PROP_ENERGY_NOW,
POWER_SUPPLY_PROP_ENERGY_FULL,
POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
};
struct bq20z75_info {
struct i2c_client *client;
struct power_supply power_supply;
};
static int bq20z75_read_word_data(struct i2c_client *client, u8 address)
{
s32 ret;
ret = i2c_smbus_read_word_data(client, address);
if (ret < 0) {
dev_err(&client->dev,
"%s: i2c read at address 0x%x failed\n",
__func__, address);
return ret;
}
return le16_to_cpu(ret);
}
static int bq20z75_write_word_data(struct i2c_client *client, u8 address,
u16 value)
{
s32 ret;
ret = i2c_smbus_write_word_data(client, address, le16_to_cpu(value));
if (ret < 0) {
dev_err(&client->dev,
"%s: i2c write to address 0x%x failed\n",
__func__, address);
return ret;
}
return 0;
}
static int bq20z75_get_battery_presence_and_health(
struct i2c_client *client, enum power_supply_property psp,
union power_supply_propval *val)
{
s32 ret;
/* Write to ManufacturerAccess with
* ManufacturerAccess command and then
* read the status */
ret = bq20z75_write_word_data(client,
bq20z75_data[REG_MANUFACTURER_DATA].addr,
MANUFACTURER_ACCESS_STATUS);
if (ret < 0)
return ret;
ret = bq20z75_read_word_data(client,
bq20z75_data[REG_MANUFACTURER_DATA].addr);
if (ret < 0)
return ret;
if (ret < bq20z75_data[REG_MANUFACTURER_DATA].min_value ||
ret > bq20z75_data[REG_MANUFACTURER_DATA].max_value) {
val->intval = 0;
return 0;
}
/* Mask the upper nibble of 2nd byte and
* lower byte of response then
* shift the result by 8 to get status*/
ret &= 0x0F00;
ret >>= 8;
if (psp == POWER_SUPPLY_PROP_PRESENT) {
if (ret == 0x0F)
/* battery removed */
val->intval = 0;
else
val->intval = 1;
} else if (psp == POWER_SUPPLY_PROP_HEALTH) {
if (ret == 0x09)
val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
else if (ret == 0x0B)
val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
else if (ret == 0x0C)
val->intval = POWER_SUPPLY_HEALTH_DEAD;
else
val->intval = POWER_SUPPLY_HEALTH_GOOD;
}
return 0;
}
static int bq20z75_get_battery_property(struct i2c_client *client,
int reg_offset, enum power_supply_property psp,
union power_supply_propval *val)
{
s32 ret;
ret = bq20z75_read_word_data(client,
bq20z75_data[reg_offset].addr);
if (ret < 0)
return ret;
/* returned values are 16 bit */
if (bq20z75_data[reg_offset].min_value < 0)
ret = (s16)ret;
if (ret >= bq20z75_data[reg_offset].min_value &&
ret <= bq20z75_data[reg_offset].max_value) {
val->intval = ret;
if (psp == POWER_SUPPLY_PROP_STATUS) {
if (ret & BATTERY_FULL_CHARGED)
val->intval = POWER_SUPPLY_STATUS_FULL;
else if (ret & BATTERY_FULL_DISCHARGED)
val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
else if (ret & BATTERY_DISCHARGING)
val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
else
val->intval = POWER_SUPPLY_STATUS_CHARGING;
}
} else {
if (psp == POWER_SUPPLY_PROP_STATUS)
val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
else
val->intval = 0;
}
return 0;
}
static void bq20z75_unit_adjustment(struct i2c_client *client,
enum power_supply_property psp, union power_supply_propval *val)
{
#define BASE_UNIT_CONVERSION 1000
#define BATTERY_MODE_CAP_MULT_WATT (10 * BASE_UNIT_CONVERSION)
#define TIME_UNIT_CONVERSION 600
#define TEMP_KELVIN_TO_CELCIUS 2731
switch (psp) {
case POWER_SUPPLY_PROP_ENERGY_NOW:
case POWER_SUPPLY_PROP_ENERGY_FULL:
case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
val->intval *= BATTERY_MODE_CAP_MULT_WATT;
break;
case POWER_SUPPLY_PROP_VOLTAGE_NOW:
case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
case POWER_SUPPLY_PROP_CURRENT_NOW:
val->intval *= BASE_UNIT_CONVERSION;
break;
case POWER_SUPPLY_PROP_TEMP:
/* bq20z75 provides battery tempreture in 0.1°K
* so convert it to 0.1°C */
val->intval -= TEMP_KELVIN_TO_CELCIUS;
val->intval *= 10;
break;
case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
val->intval *= TIME_UNIT_CONVERSION;
break;
default:
dev_dbg(&client->dev,
"%s: no need for unit conversion %d\n", __func__, psp);
}
}
static int bq20z75_get_battery_capacity(struct i2c_client *client,
int reg_offset, enum power_supply_property psp,
union power_supply_propval *val)
{
s32 ret;
ret = bq20z75_read_word_data(client, bq20z75_data[reg_offset].addr);
if (ret < 0)
return ret;
if (psp == POWER_SUPPLY_PROP_CAPACITY) {
/* bq20z75 spec says that this can be >100 %
* even if max value is 100 % */
val->intval = min(ret, 100);
} else
val->intval = ret;
return 0;
}
static char bq20z75_serial[5];
static int bq20z75_get_battery_serial_number(struct i2c_client *client,
union power_supply_propval *val)
{
int ret;
ret = bq20z75_read_word_data(client,
bq20z75_data[REG_SERIAL_NUMBER].addr);
if (ret < 0)
return ret;
ret = sprintf(bq20z75_serial, "%04x", ret);
val->strval = bq20z75_serial;
return 0;
}
static int bq20z75_get_property(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
{
int count;
int ret;
struct bq20z75_info *bq20z75_device = container_of(psy,
struct bq20z75_info, power_supply);
struct i2c_client *client = bq20z75_device->client;
switch (psp) {
case POWER_SUPPLY_PROP_PRESENT:
case POWER_SUPPLY_PROP_HEALTH:
ret = bq20z75_get_battery_presence_and_health(client, psp, val);
if (ret)
return ret;
break;
case POWER_SUPPLY_PROP_TECHNOLOGY:
val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
break;
case POWER_SUPPLY_PROP_ENERGY_NOW:
case POWER_SUPPLY_PROP_ENERGY_FULL:
case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
case POWER_SUPPLY_PROP_CAPACITY:
for (count = 0; count < ARRAY_SIZE(bq20z75_data); count++) {
if (psp == bq20z75_data[count].psp)
break;
}
ret = bq20z75_get_battery_capacity(client, count, psp, val);
if (ret)
return ret;
break;
case POWER_SUPPLY_PROP_SERIAL_NUMBER:
ret = bq20z75_get_battery_serial_number(client, val);
if (ret)
return ret;
break;
case POWER_SUPPLY_PROP_STATUS:
case POWER_SUPPLY_PROP_CYCLE_COUNT:
case POWER_SUPPLY_PROP_VOLTAGE_NOW:
case POWER_SUPPLY_PROP_CURRENT_NOW:
case POWER_SUPPLY_PROP_TEMP:
case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
for (count = 0; count < ARRAY_SIZE(bq20z75_data); count++) {
if (psp == bq20z75_data[count].psp)
break;
}
ret = bq20z75_get_battery_property(client, count, psp, val);
if (ret)
return ret;
break;
default:
dev_err(&client->dev,
"%s: INVALID property\n", __func__);
return -EINVAL;
}
/* Convert units to match requirements for power supply class */
bq20z75_unit_adjustment(client, psp, val);
dev_dbg(&client->dev,
"%s: property = %d, value = %d\n", __func__, psp, val->intval);
return 0;
}
static int bq20z75_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct bq20z75_info *bq20z75_device;
int rc;
bq20z75_device = kzalloc(sizeof(struct bq20z75_info), GFP_KERNEL);
if (!bq20z75_device)
return -ENOMEM;
bq20z75_device->client = client;
bq20z75_device->power_supply.name = "battery";
bq20z75_device->power_supply.type = POWER_SUPPLY_TYPE_BATTERY;
bq20z75_device->power_supply.properties = bq20z75_properties;
bq20z75_device->power_supply.num_properties =
ARRAY_SIZE(bq20z75_properties);
bq20z75_device->power_supply.get_property = bq20z75_get_property;
i2c_set_clientdata(client, bq20z75_device);
rc = power_supply_register(&client->dev, &bq20z75_device->power_supply);
if (rc) {
dev_err(&client->dev,
"%s: Failed to register power supply\n", __func__);
kfree(bq20z75_device);
return rc;
}
dev_info(&client->dev,
"%s: battery gas gauge device registered\n", client->name);
return 0;
}
static int bq20z75_remove(struct i2c_client *client)
{
struct bq20z75_info *bq20z75_device = i2c_get_clientdata(client);
power_supply_unregister(&bq20z75_device->power_supply);
kfree(bq20z75_device);
bq20z75_device = NULL;
return 0;
}
#if defined CONFIG_PM
static int bq20z75_suspend(struct i2c_client *client,
pm_message_t state)
{
s32 ret;
/* write to manufacturer access with sleep command */
ret = bq20z75_write_word_data(client,
bq20z75_data[REG_MANUFACTURER_DATA].addr,
MANUFACTURER_ACCESS_SLEEP);
if (ret < 0)
return ret;
return 0;
}
#else
#define bq20z75_suspend NULL
#endif
/* any smbus transaction will wake up bq20z75 */
#define bq20z75_resume NULL
static const struct i2c_device_id bq20z75_id[] = {
{ "bq20z75", 0 },
{}
};
static struct i2c_driver bq20z75_battery_driver = {
.probe = bq20z75_probe,
.remove = bq20z75_remove,
.suspend = bq20z75_suspend,
.resume = bq20z75_resume,
.id_table = bq20z75_id,
.driver = {
.name = "bq20z75-battery",
},
};
static int __init bq20z75_battery_init(void)
{
return i2c_add_driver(&bq20z75_battery_driver);
}
module_init(bq20z75_battery_init);
static void __exit bq20z75_battery_exit(void)
{
i2c_del_driver(&bq20z75_battery_driver);
}
module_exit(bq20z75_battery_exit);
MODULE_DESCRIPTION("BQ20z75 battery monitor driver");
MODULE_LICENSE("GPL");