[mirror_ubuntu-artful-kernel.git] / drivers / power / bq20z75.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>
#include <linux/interrupt.h>
#include <linux/gpio.h>

#include <linux/power/bq20z75.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_REMAINING_CAPACITY_CHARGE,
	REG_FULL_CHARGE_CAPACITY,
	REG_FULL_CHARGE_CAPACITY_CHARGE,
	REG_DESIGN_CAPACITY,
	REG_DESIGN_CAPACITY_CHARGE,
	REG_DESIGN_VOLTAGE,
};

/* Battery Mode defines */
#define BATTERY_MODE_OFFSET		0x03
#define BATTERY_MODE_MASK		0x8000
enum bq20z75_battery_mode {
	BATTERY_MODE_AMPS,
	BATTERY_MODE_WATTS
};

/* 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_REMAINING_CAPACITY_CHARGE] =
		BQ20Z75_DATA(POWER_SUPPLY_PROP_CHARGE_NOW, 0x0F, 0, 65535),
	[REG_FULL_CHARGE_CAPACITY] =
		BQ20Z75_DATA(POWER_SUPPLY_PROP_ENERGY_FULL, 0x10, 0, 65535),
	[REG_FULL_CHARGE_CAPACITY_CHARGE] =
		BQ20Z75_DATA(POWER_SUPPLY_PROP_CHARGE_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_CAPACITY_CHARGE] =
		BQ20Z75_DATA(POWER_SUPPLY_PROP_CHARGE_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,
	POWER_SUPPLY_PROP_CHARGE_NOW,
	POWER_SUPPLY_PROP_CHARGE_FULL,
	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
};

struct bq20z75_info {
	struct i2c_client		*client;
	struct power_supply		power_supply;
	struct bq20z75_platform_data	*pdata;
	bool				is_present;
	bool				gpio_detect;
	bool				enable_detection;
	int				irq;
};

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;
	struct bq20z75_info *bq20z75_device = i2c_get_clientdata(client);

	if (psp == POWER_SUPPLY_PROP_PRESENT &&
		bq20z75_device->gpio_detect) {
		ret = gpio_get_value(
			bq20z75_device->pdata->battery_detect);
		if (ret == bq20z75_device->pdata->battery_detect_present)
			val->intval = 1;
		else
			val->intval = 0;
		return 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) {
		if (psp == POWER_SUPPLY_PROP_PRESENT)
			val->intval = 0; /* battery removed */
		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:
	case POWER_SUPPLY_PROP_CHARGE_NOW:
	case POWER_SUPPLY_PROP_CHARGE_FULL:
	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
		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 enum bq20z75_battery_mode
bq20z75_set_battery_mode(struct i2c_client *client,
	enum bq20z75_battery_mode mode)
{
	int ret, original_val;

	original_val = bq20z75_read_word_data(client, BATTERY_MODE_OFFSET);
	if (original_val < 0)
		return original_val;

	if ((original_val & BATTERY_MODE_MASK) == mode)
		return mode;

	if (mode == BATTERY_MODE_AMPS)
		ret = original_val & ~BATTERY_MODE_MASK;
	else
		ret = original_val | BATTERY_MODE_MASK;

	ret = bq20z75_write_word_data(client, BATTERY_MODE_OFFSET, ret);
	if (ret < 0)
		return ret;

	return original_val & BATTERY_MODE_MASK;
}

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;
	enum bq20z75_battery_mode mode = BATTERY_MODE_WATTS;

	if (power_supply_is_amp_property(psp))
		mode = BATTERY_MODE_AMPS;

	mode = bq20z75_set_battery_mode(client, mode);
	if (mode < 0)
		return mode;

	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;

	ret = bq20z75_set_battery_mode(client, mode);
	if (ret < 0)
		return 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_index(struct i2c_client *client,
	enum power_supply_property psp)
{
	int count;
	for (count = 0; count < ARRAY_SIZE(bq20z75_data); count++)
		if (psp == bq20z75_data[count].psp)
			return count;

	dev_warn(&client->dev,
		"%s: Invalid Property - %d\n", __func__, psp);

	return -EINVAL;
}

static int bq20z75_get_property(struct power_supply *psy,
	enum power_supply_property psp,
	union power_supply_propval *val)
{
	int ret = 0;
	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);
		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_CHARGE_NOW:
	case POWER_SUPPLY_PROP_CHARGE_FULL:
	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
	case POWER_SUPPLY_PROP_CAPACITY:
		ret = bq20z75_get_property_index(client, psp);
		if (ret < 0)
			break;

		ret = bq20z75_get_battery_capacity(client, ret, psp, val);
		break;

	case POWER_SUPPLY_PROP_SERIAL_NUMBER:
		ret = bq20z75_get_battery_serial_number(client, val);
		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:
		ret = bq20z75_get_property_index(client, psp);
		if (ret < 0)
			break;

		ret = bq20z75_get_battery_property(client, ret, psp, val);
		break;

	default:
		dev_err(&client->dev,
			"%s: INVALID property\n", __func__);
		return -EINVAL;
	}

	if (!bq20z75_device->enable_detection)
		goto done;

	if (!bq20z75_device->gpio_detect &&
		bq20z75_device->is_present != (ret >= 0)) {
		bq20z75_device->is_present = (ret >= 0);
		power_supply_changed(&bq20z75_device->power_supply);
	}

done:
	if (!ret) {
		/* 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 ret;
}

static irqreturn_t bq20z75_irq(int irq, void *devid)
{
	struct power_supply *battery = devid;

	power_supply_changed(battery);

	return IRQ_HANDLED;
}

static int __devinit bq20z75_probe(struct i2c_client *client,
	const struct i2c_device_id *id)
{
	struct bq20z75_info *bq20z75_device;
	struct bq20z75_platform_data *pdata = client->dev.platform_data;
	int rc;
	int irq;

	bq20z75_device = kzalloc(sizeof(struct bq20z75_info), GFP_KERNEL);
	if (!bq20z75_device)
		return -ENOMEM;

	bq20z75_device->client = client;
	bq20z75_device->enable_detection = false;
	bq20z75_device->gpio_detect = false;
	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;

	if (pdata) {
		bq20z75_device->gpio_detect =
			gpio_is_valid(pdata->battery_detect);
		bq20z75_device->pdata = pdata;
	}

	i2c_set_clientdata(client, bq20z75_device);

	if (!bq20z75_device->gpio_detect)
		goto skip_gpio;

	rc = gpio_request(pdata->battery_detect, dev_name(&client->dev));
	if (rc) {
		dev_warn(&client->dev, "Failed to request gpio: %d\n", rc);
		bq20z75_device->gpio_detect = false;
		goto skip_gpio;
	}

	rc = gpio_direction_input(pdata->battery_detect);
	if (rc) {
		dev_warn(&client->dev, "Failed to get gpio as input: %d\n", rc);
		gpio_free(pdata->battery_detect);
		bq20z75_device->gpio_detect = false;
		goto skip_gpio;
	}

	irq = gpio_to_irq(pdata->battery_detect);
	if (irq <= 0) {
		dev_warn(&client->dev, "Failed to get gpio as irq: %d\n", irq);
		gpio_free(pdata->battery_detect);
		bq20z75_device->gpio_detect = false;
		goto skip_gpio;
	}

	rc = request_irq(irq, bq20z75_irq,
		IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
		dev_name(&client->dev), &bq20z75_device->power_supply);
	if (rc) {
		dev_warn(&client->dev, "Failed to request irq: %d\n", rc);
		gpio_free(pdata->battery_detect);
		bq20z75_device->gpio_detect = false;
		goto skip_gpio;
	}

	bq20z75_device->irq = irq;

skip_gpio:

	rc = power_supply_register(&client->dev, &bq20z75_device->power_supply);
	if (rc) {
		dev_err(&client->dev,
			"%s: Failed to register power supply\n", __func__);
		goto exit_psupply;
	}

	dev_info(&client->dev,
		"%s: battery gas gauge device registered\n", client->name);

	return 0;

exit_psupply:
	if (bq20z75_device->irq)
		free_irq(bq20z75_device->irq, &bq20z75_device->power_supply);
	if (bq20z75_device->gpio_detect)
		gpio_free(pdata->battery_detect);

	kfree(bq20z75_device);

	return rc;
}

static int __devexit bq20z75_remove(struct i2c_client *client)
{
	struct bq20z75_info *bq20z75_device = i2c_get_clientdata(client);

	if (bq20z75_device->irq)
		free_irq(bq20z75_device->irq, &bq20z75_device->power_supply);
	if (bq20z75_device->gpio_detect)
		gpio_free(bq20z75_device->pdata->battery_detect);

	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		= __devexit_p(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");
Commit	Line	Data
a7640bfa RK	1	/*
	2	* Gas Gauge driver for TI's BQ20Z75
	3	*
	4	* Copyright (c) 2010, NVIDIA Corporation.
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful, but WITHOUT
	12	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	13	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	14	* more details.
	15	*
	16	* You should have received a copy of the GNU General Public License along
	17	* with this program; if not, write to the Free Software Foundation, Inc.,
	18	* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
	19	*/
	20
	21	#include <linux/init.h>
	22	#include <linux/module.h>
	23	#include <linux/kernel.h>
	24	#include <linux/err.h>
	25	#include <linux/power_supply.h>
	26	#include <linux/i2c.h>
	27	#include <linux/slab.h>
bb879101 RK	28	#include <linux/interrupt.h>
	29	#include <linux/gpio.h>
	30
	31	#include <linux/power/bq20z75.h>
a7640bfa RK	32
	33	enum {
	34	REG_MANUFACTURER_DATA,
	35	REG_TEMPERATURE,
	36	REG_VOLTAGE,
	37	REG_CURRENT,
	38	REG_CAPACITY,
	39	REG_TIME_TO_EMPTY,
	40	REG_TIME_TO_FULL,
	41	REG_STATUS,
	42	REG_CYCLE_COUNT,
d3ab61ec RK	43	REG_SERIAL_NUMBER,
d3ab61ec RK	44	REG_REMAINING_CAPACITY,
51d07566	45	REG_REMAINING_CAPACITY_CHARGE,
d3ab61ec	46	REG_FULL_CHARGE_CAPACITY,
51d07566	47	REG_FULL_CHARGE_CAPACITY_CHARGE,
d3ab61ec	48	REG_DESIGN_CAPACITY,
51d07566	49	REG_DESIGN_CAPACITY_CHARGE,
d3ab61ec	50	REG_DESIGN_VOLTAGE,
a7640bfa RK	51	};
a7640bfa RK	52
51d07566 RK	53	/* Battery Mode defines */
	54	#define BATTERY_MODE_OFFSET 0x03
	55	#define BATTERY_MODE_MASK 0x8000
	56	enum bq20z75_battery_mode {
	57	BATTERY_MODE_AMPS,
	58	BATTERY_MODE_WATTS
	59	};
	60
a7640bfa RK	61	/* manufacturer access defines */
	62	#define MANUFACTURER_ACCESS_STATUS 0x0006
	63	#define MANUFACTURER_ACCESS_SLEEP 0x0011
	64
	65	/* battery status value bits */
d3ab61ec	66	#define BATTERY_DISCHARGING 0x40
a7640bfa RK	67	#define BATTERY_FULL_CHARGED 0x20
	68	#define BATTERY_FULL_DISCHARGED 0x10
	69
	70	#define BQ20Z75_DATA(_psp, _addr, _min_value, _max_value) { \
	71	.psp = _psp, \
	72	.addr = _addr, \
	73	.min_value = _min_value, \
	74	.max_value = _max_value, \
	75	}
	76
	77	static const struct bq20z75_device_data {
	78	enum power_supply_property psp;
	79	u8 addr;
	80	int min_value;
	81	int max_value;
	82	} bq20z75_data[] = {
	83	[REG_MANUFACTURER_DATA] =
	84	BQ20Z75_DATA(POWER_SUPPLY_PROP_PRESENT, 0x00, 0, 65535),
	85	[REG_TEMPERATURE] =
	86	BQ20Z75_DATA(POWER_SUPPLY_PROP_TEMP, 0x08, 0, 65535),
	87	[REG_VOLTAGE] =
	88	BQ20Z75_DATA(POWER_SUPPLY_PROP_VOLTAGE_NOW, 0x09, 0, 20000),
	89	[REG_CURRENT] =
	90	BQ20Z75_DATA(POWER_SUPPLY_PROP_CURRENT_NOW, 0x0A, -32768,
	91	32767),
	92	[REG_CAPACITY] =
	93	BQ20Z75_DATA(POWER_SUPPLY_PROP_CAPACITY, 0x0E, 0, 100),
d3ab61ec RK	94	[REG_REMAINING_CAPACITY] =
d3ab61ec RK	95	BQ20Z75_DATA(POWER_SUPPLY_PROP_ENERGY_NOW, 0x0F, 0, 65535),
51d07566 RK	96	[REG_REMAINING_CAPACITY_CHARGE] =
51d07566 RK	97	BQ20Z75_DATA(POWER_SUPPLY_PROP_CHARGE_NOW, 0x0F, 0, 65535),
d3ab61ec RK	98	[REG_FULL_CHARGE_CAPACITY] =
d3ab61ec RK	99	BQ20Z75_DATA(POWER_SUPPLY_PROP_ENERGY_FULL, 0x10, 0, 65535),
51d07566 RK	100	[REG_FULL_CHARGE_CAPACITY_CHARGE] =
51d07566 RK	101	BQ20Z75_DATA(POWER_SUPPLY_PROP_CHARGE_FULL, 0x10, 0, 65535),
a7640bfa RK	102	[REG_TIME_TO_EMPTY] =
	103	BQ20Z75_DATA(POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG, 0x12, 0,
	104	65535),
	105	[REG_TIME_TO_FULL] =
	106	BQ20Z75_DATA(POWER_SUPPLY_PROP_TIME_TO_FULL_AVG, 0x13, 0,
	107	65535),
	108	[REG_STATUS] =
	109	BQ20Z75_DATA(POWER_SUPPLY_PROP_STATUS, 0x16, 0, 65535),
	110	[REG_CYCLE_COUNT] =
	111	BQ20Z75_DATA(POWER_SUPPLY_PROP_CYCLE_COUNT, 0x17, 0, 65535),
d3ab61ec RK	112	[REG_DESIGN_CAPACITY] =
	113	BQ20Z75_DATA(POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN, 0x18, 0,
	114	65535),
51d07566 RK	115	[REG_DESIGN_CAPACITY_CHARGE] =
	116	BQ20Z75_DATA(POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN, 0x18, 0,
	117	65535),
d3ab61ec RK	118	[REG_DESIGN_VOLTAGE] =
	119	BQ20Z75_DATA(POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN, 0x19, 0,
	120	65535),
a7640bfa RK	121	[REG_SERIAL_NUMBER] =
	122	BQ20Z75_DATA(POWER_SUPPLY_PROP_SERIAL_NUMBER, 0x1C, 0, 65535),
	123	};
	124
	125	static enum power_supply_property bq20z75_properties[] = {
	126	POWER_SUPPLY_PROP_STATUS,
	127	POWER_SUPPLY_PROP_HEALTH,
	128	POWER_SUPPLY_PROP_PRESENT,
	129	POWER_SUPPLY_PROP_TECHNOLOGY,
	130	POWER_SUPPLY_PROP_CYCLE_COUNT,
	131	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	132	POWER_SUPPLY_PROP_CURRENT_NOW,
	133	POWER_SUPPLY_PROP_CAPACITY,
	134	POWER_SUPPLY_PROP_TEMP,
	135	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
	136	POWER_SUPPLY_PROP_TIME_TO_FULL_AVG,
	137	POWER_SUPPLY_PROP_SERIAL_NUMBER,
d3ab61ec RK	138	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
	139	POWER_SUPPLY_PROP_ENERGY_NOW,
	140	POWER_SUPPLY_PROP_ENERGY_FULL,
	141	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
51d07566 RK	142	POWER_SUPPLY_PROP_CHARGE_NOW,
	143	POWER_SUPPLY_PROP_CHARGE_FULL,
	144	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
a7640bfa RK	145	};
	146
	147	struct bq20z75_info {
bb879101 RK	148	struct i2c_client *client;
	149	struct power_supply power_supply;
	150	struct bq20z75_platform_data *pdata;
	151	bool is_present;
	152	bool gpio_detect;
	153	bool enable_detection;
	154	int irq;
a7640bfa RK	155	};
a7640bfa RK	156
d3ab61ec RK	157	static int bq20z75_read_word_data(struct i2c_client *client, u8 address)
	158	{
	159	s32 ret;
	160
	161	ret = i2c_smbus_read_word_data(client, address);
	162	if (ret < 0) {
	163	dev_err(&client->dev,
	164	"%s: i2c read at address 0x%x failed\n",
	165	__func__, address);
	166	return ret;
	167	}
	168	return le16_to_cpu(ret);
	169	}
	170
	171	static int bq20z75_write_word_data(struct i2c_client *client, u8 address,
	172	u16 value)
	173	{
	174	s32 ret;
	175
	176	ret = i2c_smbus_write_word_data(client, address, le16_to_cpu(value));
	177	if (ret < 0) {
	178	dev_err(&client->dev,
	179	"%s: i2c write to address 0x%x failed\n",
	180	__func__, address);
	181	return ret;
	182	}
	183	return 0;
	184	}
	185
a7640bfa RK	186	static int bq20z75_get_battery_presence_and_health(
	187	struct i2c_client *client, enum power_supply_property psp,
	188	union power_supply_propval *val)
	189	{
	190	s32 ret;
bb879101 RK	191	struct bq20z75_info *bq20z75_device = i2c_get_clientdata(client);
	192
	193	if (psp == POWER_SUPPLY_PROP_PRESENT &&
	194	bq20z75_device->gpio_detect) {
	195	ret = gpio_get_value(
	196	bq20z75_device->pdata->battery_detect);
	197	if (ret == bq20z75_device->pdata->battery_detect_present)
	198	val->intval = 1;
	199	else
	200	val->intval = 0;
	201	return ret;
	202	}
a7640bfa RK	203
	204	/* Write to ManufacturerAccess with
	205	* ManufacturerAccess command and then
	206	* read the status */
d3ab61ec	207	ret = bq20z75_write_word_data(client,
a7640bfa RK	208	bq20z75_data[REG_MANUFACTURER_DATA].addr,
a7640bfa RK	209	MANUFACTURER_ACCESS_STATUS);
d3ab61ec RK	210	if (ret < 0)
d3ab61ec RK	211	return ret;
a7640bfa	212
d3ab61ec RK	213
d3ab61ec RK	214	ret = bq20z75_read_word_data(client,
a7640bfa	215	bq20z75_data[REG_MANUFACTURER_DATA].addr);
bb879101 RK	216	if (ret < 0) {
	217	if (psp == POWER_SUPPLY_PROP_PRESENT)
	218	val->intval = 0; /* battery removed */
d3ab61ec	219	return ret;
bb879101	220	}
a7640bfa RK	221
	222	if (ret < bq20z75_data[REG_MANUFACTURER_DATA].min_value \|\|
	223	ret > bq20z75_data[REG_MANUFACTURER_DATA].max_value) {
	224	val->intval = 0;
	225	return 0;
	226	}
	227
	228	/* Mask the upper nibble of 2nd byte and
	229	* lower byte of response then
	230	* shift the result by 8 to get status*/
	231	ret &= 0x0F00;
	232	ret >>= 8;
	233	if (psp == POWER_SUPPLY_PROP_PRESENT) {
	234	if (ret == 0x0F)
	235	/* battery removed */
	236	val->intval = 0;
	237	else
	238	val->intval = 1;
	239	} else if (psp == POWER_SUPPLY_PROP_HEALTH) {
	240	if (ret == 0x09)
	241	val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
	242	else if (ret == 0x0B)
	243	val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
	244	else if (ret == 0x0C)
	245	val->intval = POWER_SUPPLY_HEALTH_DEAD;
	246	else
	247	val->intval = POWER_SUPPLY_HEALTH_GOOD;
	248	}
	249
	250	return 0;
	251	}
	252
	253	static int bq20z75_get_battery_property(struct i2c_client *client,
	254	int reg_offset, enum power_supply_property psp,
	255	union power_supply_propval *val)
	256	{
	257	s32 ret;
	258
d3ab61ec	259	ret = bq20z75_read_word_data(client,
a7640bfa	260	bq20z75_data[reg_offset].addr);
d3ab61ec RK	261	if (ret < 0)
	262	return ret;
	263
	264	/* returned values are 16 bit */
	265	if (bq20z75_data[reg_offset].min_value < 0)
	266	ret = (s16)ret;
a7640bfa RK	267
	268	if (ret >= bq20z75_data[reg_offset].min_value &&
	269	ret <= bq20z75_data[reg_offset].max_value) {
	270	val->intval = ret;
	271	if (psp == POWER_SUPPLY_PROP_STATUS) {
d3ab61ec	272	if (ret & BATTERY_FULL_CHARGED)
a7640bfa RK	273	val->intval = POWER_SUPPLY_STATUS_FULL;
	274	else if (ret & BATTERY_FULL_DISCHARGED)
	275	val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
d3ab61ec	276	else if (ret & BATTERY_DISCHARGING)
a7640bfa	277	val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
d3ab61ec RK	278	else
d3ab61ec RK	279	val->intval = POWER_SUPPLY_STATUS_CHARGING;
a7640bfa	280	}
a7640bfa RK	281	} else {
	282	if (psp == POWER_SUPPLY_PROP_STATUS)
	283	val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
	284	else
	285	val->intval = 0;
	286	}
	287
	288	return 0;
	289	}
	290
d3ab61ec RK	291	static void bq20z75_unit_adjustment(struct i2c_client *client,
	292	enum power_supply_property psp, union power_supply_propval *val)
	293	{
	294	#define BASE_UNIT_CONVERSION 1000
	295	#define BATTERY_MODE_CAP_MULT_WATT (10 * BASE_UNIT_CONVERSION)
	296	#define TIME_UNIT_CONVERSION 600
	297	#define TEMP_KELVIN_TO_CELCIUS 2731
	298	switch (psp) {
	299	case POWER_SUPPLY_PROP_ENERGY_NOW:
	300	case POWER_SUPPLY_PROP_ENERGY_FULL:
	301	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
	302	val->intval *= BATTERY_MODE_CAP_MULT_WATT;
	303	break;
	304
	305	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
	306	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
	307	case POWER_SUPPLY_PROP_CURRENT_NOW:
51d07566 RK	308	case POWER_SUPPLY_PROP_CHARGE_NOW:
	309	case POWER_SUPPLY_PROP_CHARGE_FULL:
	310	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
d3ab61ec RK	311	val->intval *= BASE_UNIT_CONVERSION;
	312	break;
	313
	314	case POWER_SUPPLY_PROP_TEMP:
	315	/* bq20z75 provides battery tempreture in 0.1°K
	316	* so convert it to 0.1°C */
	317	val->intval -= TEMP_KELVIN_TO_CELCIUS;
	318	val->intval *= 10;
	319	break;
	320
	321	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
	322	case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
	323	val->intval *= TIME_UNIT_CONVERSION;
	324	break;
	325
	326	default:
	327	dev_dbg(&client->dev,
	328	"%s: no need for unit conversion %d\n", __func__, psp);
	329	}
	330	}
	331
51d07566 RK	332	static enum bq20z75_battery_mode
	333	bq20z75_set_battery_mode(struct i2c_client *client,
	334	enum bq20z75_battery_mode mode)
	335	{
	336	int ret, original_val;
	337
	338	original_val = bq20z75_read_word_data(client, BATTERY_MODE_OFFSET);
	339	if (original_val < 0)
	340	return original_val;
	341
	342	if ((original_val & BATTERY_MODE_MASK) == mode)
	343	return mode;
	344
	345	if (mode == BATTERY_MODE_AMPS)
	346	ret = original_val & ~BATTERY_MODE_MASK;
	347	else
	348	ret = original_val \| BATTERY_MODE_MASK;
	349
	350	ret = bq20z75_write_word_data(client, BATTERY_MODE_OFFSET, ret);
	351	if (ret < 0)
	352	return ret;
	353
	354	return original_val & BATTERY_MODE_MASK;
	355	}
	356
a7640bfa	357	static int bq20z75_get_battery_capacity(struct i2c_client *client,
d3ab61ec	358	int reg_offset, enum power_supply_property psp,
a7640bfa RK	359	union power_supply_propval *val)
	360	{
	361	s32 ret;
51d07566 RK	362	enum bq20z75_battery_mode mode = BATTERY_MODE_WATTS;
	363
	364	if (power_supply_is_amp_property(psp))
	365	mode = BATTERY_MODE_AMPS;
	366
	367	mode = bq20z75_set_battery_mode(client, mode);
	368	if (mode < 0)
	369	return mode;
a7640bfa	370
d3ab61ec RK	371	ret = bq20z75_read_word_data(client, bq20z75_data[reg_offset].addr);
	372	if (ret < 0)
	373	return ret;
a7640bfa	374
d3ab61ec RK	375	if (psp == POWER_SUPPLY_PROP_CAPACITY) {
	376	/* bq20z75 spec says that this can be >100 %
	377	* even if max value is 100 % */
	378	val->intval = min(ret, 100);
	379	} else
	380	val->intval = ret;
	381
51d07566 RK	382	ret = bq20z75_set_battery_mode(client, mode);
	383	if (ret < 0)
	384	return ret;
	385
d3ab61ec RK	386	return 0;
	387	}
	388
	389	static char bq20z75_serial[5];
	390	static int bq20z75_get_battery_serial_number(struct i2c_client *client,
	391	union power_supply_propval *val)
	392	{
	393	int ret;
	394
	395	ret = bq20z75_read_word_data(client,
	396	bq20z75_data[REG_SERIAL_NUMBER].addr);
	397	if (ret < 0)
	398	return ret;
	399
	400	ret = sprintf(bq20z75_serial, "%04x", ret);
	401	val->strval = bq20z75_serial;
a7640bfa RK	402
	403	return 0;
	404	}
	405
51d07566 RK	406	static int bq20z75_get_property_index(struct i2c_client *client,
	407	enum power_supply_property psp)
	408	{
	409	int count;
	410	for (count = 0; count < ARRAY_SIZE(bq20z75_data); count++)
	411	if (psp == bq20z75_data[count].psp)
	412	return count;
	413
	414	dev_warn(&client->dev,
	415	"%s: Invalid Property - %d\n", __func__, psp);
	416
	417	return -EINVAL;
	418	}
	419
a7640bfa RK	420	static int bq20z75_get_property(struct power_supply *psy,
	421	enum power_supply_property psp,
	422	union power_supply_propval *val)
	423	{
bb879101	424	int ret = 0;
a7640bfa RK	425	struct bq20z75_info *bq20z75_device = container_of(psy,
	426	struct bq20z75_info, power_supply);
	427	struct i2c_client *client = bq20z75_device->client;
	428
	429	switch (psp) {
	430	case POWER_SUPPLY_PROP_PRESENT:
	431	case POWER_SUPPLY_PROP_HEALTH:
	432	ret = bq20z75_get_battery_presence_and_health(client, psp, val);
a7640bfa RK	433	break;
	434
	435	case POWER_SUPPLY_PROP_TECHNOLOGY:
	436	val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
	437	break;
	438
d3ab61ec RK	439	case POWER_SUPPLY_PROP_ENERGY_NOW:
	440	case POWER_SUPPLY_PROP_ENERGY_FULL:
	441	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
51d07566 RK	442	case POWER_SUPPLY_PROP_CHARGE_NOW:
	443	case POWER_SUPPLY_PROP_CHARGE_FULL:
	444	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
a7640bfa	445	case POWER_SUPPLY_PROP_CAPACITY:
bb879101 RK	446	ret = bq20z75_get_property_index(client, psp);
	447	if (ret < 0)
	448	break;
d3ab61ec	449
bb879101	450	ret = bq20z75_get_battery_capacity(client, ret, psp, val);
d3ab61ec RK	451	break;
	452
	453	case POWER_SUPPLY_PROP_SERIAL_NUMBER:
	454	ret = bq20z75_get_battery_serial_number(client, val);
a7640bfa RK	455	break;
	456
	457	case POWER_SUPPLY_PROP_STATUS:
	458	case POWER_SUPPLY_PROP_CYCLE_COUNT:
	459	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
	460	case POWER_SUPPLY_PROP_CURRENT_NOW:
	461	case POWER_SUPPLY_PROP_TEMP:
	462	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
	463	case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
d3ab61ec	464	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
bb879101 RK	465	ret = bq20z75_get_property_index(client, psp);
	466	if (ret < 0)
	467	break;
d3ab61ec	468
bb879101	469	ret = bq20z75_get_battery_property(client, ret, psp, val);
a7640bfa RK	470	break;
	471
	472	default:
	473	dev_err(&client->dev,
	474	"%s: INVALID property\n", __func__);
	475	return -EINVAL;
	476	}
	477
bb879101 RK	478	if (!bq20z75_device->enable_detection)
	479	goto done;
	480
	481	if (!bq20z75_device->gpio_detect &&
	482	bq20z75_device->is_present != (ret >= 0)) {
	483	bq20z75_device->is_present = (ret >= 0);
	484	power_supply_changed(&bq20z75_device->power_supply);
	485	}
	486
	487	done:
	488	if (!ret) {
	489	/* Convert units to match requirements for power supply class */
	490	bq20z75_unit_adjustment(client, psp, val);
	491	}
d3ab61ec	492
a7640bfa RK	493	dev_dbg(&client->dev,
	494	"%s: property = %d, value = %d\n", __func__, psp, val->intval);
	495
bb879101	496	return ret;
a7640bfa RK	497	}
a7640bfa RK	498
bb879101 RK	499	static irqreturn_t bq20z75_irq(int irq, void *devid)
	500	{
	501	struct power_supply *battery = devid;
	502
	503	power_supply_changed(battery);
	504
	505	return IRQ_HANDLED;
	506	}
	507
	508	static int __devinit bq20z75_probe(struct i2c_client *client,
a7640bfa RK	509	const struct i2c_device_id *id)
	510	{
	511	struct bq20z75_info *bq20z75_device;
bb879101	512	struct bq20z75_platform_data *pdata = client->dev.platform_data;
a7640bfa	513	int rc;
bb879101	514	int irq;
a7640bfa RK	515
	516	bq20z75_device = kzalloc(sizeof(struct bq20z75_info), GFP_KERNEL);
	517	if (!bq20z75_device)
	518	return -ENOMEM;
	519
	520	bq20z75_device->client = client;
bb879101 RK	521	bq20z75_device->enable_detection = false;
bb879101 RK	522	bq20z75_device->gpio_detect = false;
a7640bfa RK	523	bq20z75_device->power_supply.name = "battery";
	524	bq20z75_device->power_supply.type = POWER_SUPPLY_TYPE_BATTERY;
	525	bq20z75_device->power_supply.properties = bq20z75_properties;
	526	bq20z75_device->power_supply.num_properties =
	527	ARRAY_SIZE(bq20z75_properties);
	528	bq20z75_device->power_supply.get_property = bq20z75_get_property;
	529
bb879101 RK	530	if (pdata) {
	531	bq20z75_device->gpio_detect =
	532	gpio_is_valid(pdata->battery_detect);
	533	bq20z75_device->pdata = pdata;
	534	}
	535
a7640bfa RK	536	i2c_set_clientdata(client, bq20z75_device);
a7640bfa RK	537
bb879101 RK	538	if (!bq20z75_device->gpio_detect)
	539	goto skip_gpio;
	540
	541	rc = gpio_request(pdata->battery_detect, dev_name(&client->dev));
	542	if (rc) {
	543	dev_warn(&client->dev, "Failed to request gpio: %d\n", rc);
	544	bq20z75_device->gpio_detect = false;
	545	goto skip_gpio;
	546	}
	547
	548	rc = gpio_direction_input(pdata->battery_detect);
	549	if (rc) {
	550	dev_warn(&client->dev, "Failed to get gpio as input: %d\n", rc);
	551	gpio_free(pdata->battery_detect);
	552	bq20z75_device->gpio_detect = false;
	553	goto skip_gpio;
	554	}
	555
	556	irq = gpio_to_irq(pdata->battery_detect);
	557	if (irq <= 0) {
	558	dev_warn(&client->dev, "Failed to get gpio as irq: %d\n", irq);
	559	gpio_free(pdata->battery_detect);
	560	bq20z75_device->gpio_detect = false;
	561	goto skip_gpio;
	562	}
	563
	564	rc = request_irq(irq, bq20z75_irq,
	565	IRQF_TRIGGER_RISING \| IRQF_TRIGGER_FALLING,
	566	dev_name(&client->dev), &bq20z75_device->power_supply);
	567	if (rc) {
	568	dev_warn(&client->dev, "Failed to request irq: %d\n", rc);
	569	gpio_free(pdata->battery_detect);
	570	bq20z75_device->gpio_detect = false;
	571	goto skip_gpio;
	572	}
	573
	574	bq20z75_device->irq = irq;
	575
	576	skip_gpio:
	577
a7640bfa RK	578	rc = power_supply_register(&client->dev, &bq20z75_device->power_supply);
	579	if (rc) {
	580	dev_err(&client->dev,
	581	"%s: Failed to register power supply\n", __func__);
bb879101	582	goto exit_psupply;
a7640bfa RK	583	}
	584
	585	dev_info(&client->dev,
	586	"%s: battery gas gauge device registered\n", client->name);
	587
	588	return 0;
bb879101 RK	589
	590	exit_psupply:
	591	if (bq20z75_device->irq)
	592	free_irq(bq20z75_device->irq, &bq20z75_device->power_supply);
	593	if (bq20z75_device->gpio_detect)
	594	gpio_free(pdata->battery_detect);
	595
	596	kfree(bq20z75_device);
	597
	598	return rc;
a7640bfa RK	599	}
a7640bfa RK	600
bb879101	601	static int __devexit bq20z75_remove(struct i2c_client *client)
a7640bfa RK	602	{
	603	struct bq20z75_info *bq20z75_device = i2c_get_clientdata(client);
	604
bb879101 RK	605	if (bq20z75_device->irq)
	606	free_irq(bq20z75_device->irq, &bq20z75_device->power_supply);
	607	if (bq20z75_device->gpio_detect)
	608	gpio_free(bq20z75_device->pdata->battery_detect);
	609
a7640bfa RK	610	power_supply_unregister(&bq20z75_device->power_supply);
	611	kfree(bq20z75_device);
	612	bq20z75_device = NULL;
	613
	614	return 0;
	615	}
	616
	617	#if defined CONFIG_PM
	618	static int bq20z75_suspend(struct i2c_client *client,
	619	pm_message_t state)
	620	{
	621	s32 ret;
	622
	623	/* write to manufacturer access with sleep command */
d3ab61ec	624	ret = bq20z75_write_word_data(client,
a7640bfa RK	625	bq20z75_data[REG_MANUFACTURER_DATA].addr,
a7640bfa RK	626	MANUFACTURER_ACCESS_SLEEP);
d3ab61ec RK	627	if (ret < 0)
d3ab61ec RK	628	return ret;
a7640bfa RK	629
	630	return 0;
	631	}
	632	#else
	633	#define bq20z75_suspend NULL
	634	#endif
	635	/* any smbus transaction will wake up bq20z75 */
	636	#define bq20z75_resume NULL
	637
	638	static const struct i2c_device_id bq20z75_id[] = {
	639	{ "bq20z75", 0 },
	640	{}
	641	};
	642
	643	static struct i2c_driver bq20z75_battery_driver = {
	644	.probe = bq20z75_probe,
bb879101	645	.remove = __devexit_p(bq20z75_remove),
a7640bfa RK	646	.suspend = bq20z75_suspend,
	647	.resume = bq20z75_resume,
	648	.id_table = bq20z75_id,
	649	.driver = {
	650	.name = "bq20z75-battery",
	651	},
	652	};
	653
	654	static int __init bq20z75_battery_init(void)
	655	{
	656	return i2c_add_driver(&bq20z75_battery_driver);
	657	}
	658	module_init(bq20z75_battery_init);
	659
	660	static void __exit bq20z75_battery_exit(void)
	661	{
	662	i2c_del_driver(&bq20z75_battery_driver);
	663	}
	664	module_exit(bq20z75_battery_exit);
	665
	666	MODULE_DESCRIPTION("BQ20z75 battery monitor driver");
	667	MODULE_LICENSE("GPL");