[deliverable/linux.git] / drivers / power / ds2782_battery.c

/*
 * I2C client/driver for the Maxim/Dallas DS2782 Stand-Alone Fuel Gauge IC
 *
 * Copyright (C) 2009 Bluewater Systems Ltd
 *
 * Author: Ryan Mallon
 *
 * DS2786 added by Yulia Vilensky <vilensky@compulab.co.il>
 *
 * UEvent sending added by Evgeny Romanov <romanov@neurosoft.ru>
 *
 * 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/types.h>
#include <linux/errno.h>
#include <linux/swab.h>
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/idr.h>
#include <linux/power_supply.h>
#include <linux/slab.h>
#include <linux/ds2782_battery.h>

#define DS2782_REG_RARC		0x06	/* Remaining active relative capacity */

#define DS278x_REG_VOLT_MSB	0x0c
#define DS278x_REG_TEMP_MSB	0x0a
#define DS278x_REG_CURRENT_MSB	0x0e

/* EEPROM Block */
#define DS2782_REG_RSNSP	0x69	/* Sense resistor value */

/* Current unit measurement in uA for a 1 milli-ohm sense resistor */
#define DS2782_CURRENT_UNITS	1563

#define DS2786_REG_RARC		0x02	/* Remaining active relative capacity */

#define DS2786_CURRENT_UNITS	25

#define DS278x_DELAY		1000

struct ds278x_info;

struct ds278x_battery_ops {
	int (*get_battery_current)(struct ds278x_info *info, int *current_uA);
	int (*get_battery_voltage)(struct ds278x_info *info, int *voltage_uV);
	int (*get_battery_capacity)(struct ds278x_info *info, int *capacity);
};

#define to_ds278x_info(x) container_of(x, struct ds278x_info, battery)

struct ds278x_info {
	struct i2c_client	*client;
	struct power_supply	battery;
	struct ds278x_battery_ops  *ops;
	struct delayed_work	bat_work;
	int			id;
	int                     rsns;
	int			capacity;
	int			status;		/* State Of Charge */
};

static DEFINE_IDR(battery_id);
static DEFINE_MUTEX(battery_lock);

static inline int ds278x_read_reg(struct ds278x_info *info, int reg, u8 *val)
{
	int ret;

	ret = i2c_smbus_read_byte_data(info->client, reg);
	if (ret < 0) {
		dev_err(&info->client->dev, "register read failed\n");
		return ret;
	}

	*val = ret;
	return 0;
}

static inline int ds278x_read_reg16(struct ds278x_info *info, int reg_msb,
				    s16 *val)
{
	int ret;

	ret = i2c_smbus_read_word_data(info->client, reg_msb);
	if (ret < 0) {
		dev_err(&info->client->dev, "register read failed\n");
		return ret;
	}

	*val = swab16(ret);
	return 0;
}

static int ds278x_get_temp(struct ds278x_info *info, int *temp)
{
	s16 raw;
	int err;

	/*
	 * Temperature is measured in units of 0.125 degrees celcius, the
	 * power_supply class measures temperature in tenths of degrees
	 * celsius. The temperature value is stored as a 10 bit number, plus
	 * sign in the upper bits of a 16 bit register.
	 */
	err = ds278x_read_reg16(info, DS278x_REG_TEMP_MSB, &raw);
	if (err)
		return err;
	*temp = ((raw / 32) * 125) / 100;
	return 0;
}

static int ds2782_get_current(struct ds278x_info *info, int *current_uA)
{
	int sense_res;
	int err;
	u8 sense_res_raw;
	s16 raw;

	/*
	 * The units of measurement for current are dependent on the value of
	 * the sense resistor.
	 */
	err = ds278x_read_reg(info, DS2782_REG_RSNSP, &sense_res_raw);
	if (err)
		return err;
	if (sense_res_raw == 0) {
		dev_err(&info->client->dev, "sense resistor value is 0\n");
		return -ENXIO;
	}
	sense_res = 1000 / sense_res_raw;

	dev_dbg(&info->client->dev, "sense resistor = %d milli-ohms\n",
		sense_res);
	err = ds278x_read_reg16(info, DS278x_REG_CURRENT_MSB, &raw);
	if (err)
		return err;
	*current_uA = raw * (DS2782_CURRENT_UNITS / sense_res);
	return 0;
}

static int ds2782_get_voltage(struct ds278x_info *info, int *voltage_uV)
{
	s16 raw;
	int err;

	/*
	 * Voltage is measured in units of 4.88mV. The voltage is stored as
	 * a 10-bit number plus sign, in the upper bits of a 16-bit register
	 */
	err = ds278x_read_reg16(info, DS278x_REG_VOLT_MSB, &raw);
	if (err)
		return err;
	*voltage_uV = (raw / 32) * 4800;
	return 0;
}

static int ds2782_get_capacity(struct ds278x_info *info, int *capacity)
{
	int err;
	u8 raw;

	err = ds278x_read_reg(info, DS2782_REG_RARC, &raw);
	if (err)
		return err;
	*capacity = raw;
	return 0;
}

static int ds2786_get_current(struct ds278x_info *info, int *current_uA)
{
	int err;
	s16 raw;

	err = ds278x_read_reg16(info, DS278x_REG_CURRENT_MSB, &raw);
	if (err)
		return err;
	*current_uA = (raw / 16) * (DS2786_CURRENT_UNITS / info->rsns);
	return 0;
}

static int ds2786_get_voltage(struct ds278x_info *info, int *voltage_uV)
{
	s16 raw;
	int err;

	/*
	 * Voltage is measured in units of 1.22mV. The voltage is stored as
	 * a 10-bit number plus sign, in the upper bits of a 16-bit register
	 */
	err = ds278x_read_reg16(info, DS278x_REG_VOLT_MSB, &raw);
	if (err)
		return err;
	*voltage_uV = (raw / 8) * 1220;
	return 0;
}

static int ds2786_get_capacity(struct ds278x_info *info, int *capacity)
{
	int err;
	u8 raw;

	err = ds278x_read_reg(info, DS2786_REG_RARC, &raw);
	if (err)
		return err;
	/* Relative capacity is displayed with resolution 0.5 % */
	*capacity = raw/2 ;
	return 0;
}

static int ds278x_get_status(struct ds278x_info *info, int *status)
{
	int err;
	int current_uA;
	int capacity;

	err = info->ops->get_battery_current(info, &current_uA);
	if (err)
		return err;

	err = info->ops->get_battery_capacity(info, &capacity);
	if (err)
		return err;

	info->capacity = capacity;

	if (capacity == 100)
		*status = POWER_SUPPLY_STATUS_FULL;
	else if (current_uA == 0)
		*status = POWER_SUPPLY_STATUS_NOT_CHARGING;
	else if (current_uA < 0)
		*status = POWER_SUPPLY_STATUS_DISCHARGING;
	else
		*status = POWER_SUPPLY_STATUS_CHARGING;

	return 0;
}

static int ds278x_battery_get_property(struct power_supply *psy,
				       enum power_supply_property prop,
				       union power_supply_propval *val)
{
	struct ds278x_info *info = to_ds278x_info(psy);
	int ret;

	switch (prop) {
	case POWER_SUPPLY_PROP_STATUS:
		ret = ds278x_get_status(info, &val->intval);
		break;

	case POWER_SUPPLY_PROP_CAPACITY:
		ret = info->ops->get_battery_capacity(info, &val->intval);
		break;

	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
		ret = info->ops->get_battery_voltage(info, &val->intval);
		break;

	case POWER_SUPPLY_PROP_CURRENT_NOW:
		ret = info->ops->get_battery_current(info, &val->intval);
		break;

	case POWER_SUPPLY_PROP_TEMP:
		ret = ds278x_get_temp(info, &val->intval);
		break;

	default:
		ret = -EINVAL;
	}

	return ret;
}

static void ds278x_bat_update(struct ds278x_info *info)
{
	int old_status = info->status;
	int old_capacity = info->capacity;

	ds278x_get_status(info, &info->status);

	if ((old_status != info->status) || (old_capacity != info->capacity))
		power_supply_changed(&info->battery);
}

static void ds278x_bat_work(struct work_struct *work)
{
	struct ds278x_info *info;

	info = container_of(work, struct ds278x_info, bat_work.work);
	ds278x_bat_update(info);

	schedule_delayed_work(&info->bat_work, DS278x_DELAY);
}

static enum power_supply_property ds278x_battery_props[] = {
	POWER_SUPPLY_PROP_STATUS,
	POWER_SUPPLY_PROP_CAPACITY,
	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	POWER_SUPPLY_PROP_CURRENT_NOW,
	POWER_SUPPLY_PROP_TEMP,
};

static void ds278x_power_supply_init(struct power_supply *battery)
{
	battery->type			= POWER_SUPPLY_TYPE_BATTERY;
	battery->properties		= ds278x_battery_props;
	battery->num_properties		= ARRAY_SIZE(ds278x_battery_props);
	battery->get_property		= ds278x_battery_get_property;
	battery->external_power_changed	= NULL;
}

static int ds278x_battery_remove(struct i2c_client *client)
{
	struct ds278x_info *info = i2c_get_clientdata(client);

	power_supply_unregister(&info->battery);
	kfree(info->battery.name);

	mutex_lock(&battery_lock);
	idr_remove(&battery_id, info->id);
	mutex_unlock(&battery_lock);

	cancel_delayed_work(&info->bat_work);

	kfree(info);
	return 0;
}

#ifdef CONFIG_PM

static int ds278x_suspend(struct i2c_client *client,
		pm_message_t state)
{
	struct ds278x_info *info = i2c_get_clientdata(client);

	cancel_delayed_work(&info->bat_work);
	return 0;
}

static int ds278x_resume(struct i2c_client *client)
{
	struct ds278x_info *info = i2c_get_clientdata(client);

	schedule_delayed_work(&info->bat_work, DS278x_DELAY);
	return 0;
}

#else

#define ds278x_suspend NULL
#define ds278x_resume NULL

#endif /* CONFIG_PM */


enum ds278x_num_id {
	DS2782 = 0,
	DS2786,
};

static struct ds278x_battery_ops ds278x_ops[] = {
	[DS2782] = {
		.get_battery_current  = ds2782_get_current,
		.get_battery_voltage  = ds2782_get_voltage,
		.get_battery_capacity = ds2782_get_capacity,
	},
	[DS2786] = {
		.get_battery_current  = ds2786_get_current,
		.get_battery_voltage  = ds2786_get_voltage,
		.get_battery_capacity = ds2786_get_capacity,
	}
};

static int ds278x_battery_probe(struct i2c_client *client,
				const struct i2c_device_id *id)
{
	struct ds278x_platform_data *pdata = client->dev.platform_data;
	struct ds278x_info *info;
	int ret;
	int num;

	/*
	 * ds2786 should have the sense resistor value set
	 * in the platform data
	 */
	if (id->driver_data == DS2786 && !pdata) {
		dev_err(&client->dev, "missing platform data for ds2786\n");
		return -EINVAL;
	}

	/* Get an ID for this battery */
	ret = idr_pre_get(&battery_id, GFP_KERNEL);
	if (ret == 0) {
		ret = -ENOMEM;
		goto fail_id;
	}

	mutex_lock(&battery_lock);
	ret = idr_get_new(&battery_id, client, &num);
	mutex_unlock(&battery_lock);
	if (ret < 0)
		goto fail_id;

	info = kzalloc(sizeof(*info), GFP_KERNEL);
	if (!info) {
		ret = -ENOMEM;
		goto fail_info;
	}

	info->battery.name = kasprintf(GFP_KERNEL, "%s-%d", client->name, num);
	if (!info->battery.name) {
		ret = -ENOMEM;
		goto fail_name;
	}

	if (id->driver_data == DS2786)
		info->rsns = pdata->rsns;

	i2c_set_clientdata(client, info);
	info->client = client;
	info->id = num;
	info->ops  = &ds278x_ops[id->driver_data];
	ds278x_power_supply_init(&info->battery);

	info->capacity = 100;
	info->status = POWER_SUPPLY_STATUS_FULL;

	INIT_DELAYED_WORK(&info->bat_work, ds278x_bat_work);

	ret = power_supply_register(&client->dev, &info->battery);
	if (ret) {
		dev_err(&client->dev, "failed to register battery\n");
		goto fail_register;
	} else {
		schedule_delayed_work(&info->bat_work, DS278x_DELAY);
	}

	return 0;

fail_register:
	kfree(info->battery.name);
fail_name:
	kfree(info);
fail_info:
	mutex_lock(&battery_lock);
	idr_remove(&battery_id, num);
	mutex_unlock(&battery_lock);
fail_id:
	return ret;
}

static const struct i2c_device_id ds278x_id[] = {
	{"ds2782", DS2782},
	{"ds2786", DS2786},
	{},
};
MODULE_DEVICE_TABLE(i2c, ds278x_id);

static struct i2c_driver ds278x_battery_driver = {
	.driver 	= {
		.name	= "ds2782-battery",
	},
	.probe		= ds278x_battery_probe,
	.remove		= ds278x_battery_remove,
	.suspend	= ds278x_suspend,
	.resume		= ds278x_resume,
	.id_table	= ds278x_id,
};
module_i2c_driver(ds278x_battery_driver);

MODULE_AUTHOR("Ryan Mallon");
MODULE_DESCRIPTION("Maxim/Dallas DS2782 Stand-Alone Fuel Gauage IC driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
bfdb46ce RM	1	/*
	2	* I2C client/driver for the Maxim/Dallas DS2782 Stand-Alone Fuel Gauge IC
	3	*
	4	* Copyright (C) 2009 Bluewater Systems Ltd
	5	*
1c5454ee	6	* Author: Ryan Mallon
bfdb46ce	7	*
9b9ade6b YV	8	* DS2786 added by Yulia Vilensky <vilensky@compulab.co.il>
9b9ade6b YV	9	*
7cee9aef ER	10	* UEvent sending added by Evgeny Romanov <romanov@neurosoft.ru>
7cee9aef ER	11	*
bfdb46ce RM	12	* This program is free software; you can redistribute it and/or modify
	13	* it under the terms of the GNU General Public License version 2 as
	14	* published by the Free Software Foundation.
	15	*
	16	*/
	17
	18	#include <linux/kernel.h>
	19	#include <linux/module.h>
	20	#include <linux/types.h>
	21	#include <linux/errno.h>
	22	#include <linux/swab.h>
	23	#include <linux/i2c.h>
7cee9aef	24	#include <linux/delay.h>
bfdb46ce RM	25	#include <linux/idr.h>
bfdb46ce RM	26	#include <linux/power_supply.h>
5a0e3ad6	27	#include <linux/slab.h>
9b9ade6b	28	#include <linux/ds2782_battery.h>
bfdb46ce RM	29
	30	#define DS2782_REG_RARC 0x06 /* Remaining active relative capacity */
	31
9b9ade6b YV	32	#define DS278x_REG_VOLT_MSB 0x0c
	33	#define DS278x_REG_TEMP_MSB 0x0a
	34	#define DS278x_REG_CURRENT_MSB 0x0e
bfdb46ce RM	35
	36	/* EEPROM Block */
	37	#define DS2782_REG_RSNSP 0x69 /* Sense resistor value */
	38
	39	/* Current unit measurement in uA for a 1 milli-ohm sense resistor */
	40	#define DS2782_CURRENT_UNITS 1563
	41
9b9ade6b YV	42	#define DS2786_REG_RARC 0x02 /* Remaining active relative capacity */
	43
	44	#define DS2786_CURRENT_UNITS 25
	45
7cee9aef ER	46	#define DS278x_DELAY 1000
7cee9aef ER	47
9b9ade6b YV	48	struct ds278x_info;
	49
	50	struct ds278x_battery_ops {
eb9650d6	51	int (get_battery_current)(struct ds278x_info info, int *current_uA);
353f867b RM	52	int (get_battery_voltage)(struct ds278x_info info, int *voltage_uV);
353f867b RM	53	int (get_battery_capacity)(struct ds278x_info info, int *capacity);
9b9ade6b YV	54	};
	55
	56	#define to_ds278x_info(x) container_of(x, struct ds278x_info, battery)
bfdb46ce	57
9b9ade6b	58	struct ds278x_info {
bfdb46ce RM	59	struct i2c_client *client;
bfdb46ce RM	60	struct power_supply battery;
9b9ade6b	61	struct ds278x_battery_ops *ops;
7cee9aef	62	struct delayed_work bat_work;
bfdb46ce	63	int id;
9b9ade6b	64	int rsns;
7cee9aef ER	65	int capacity;
7cee9aef ER	66	int status; /* State Of Charge */
bfdb46ce RM	67	};
	68
	69	static DEFINE_IDR(battery_id);
	70	static DEFINE_MUTEX(battery_lock);
	71
9b9ade6b	72	static inline int ds278x_read_reg(struct ds278x_info info, int reg, u8 val)
bfdb46ce RM	73	{
	74	int ret;
	75
	76	ret = i2c_smbus_read_byte_data(info->client, reg);
	77	if (ret < 0) {
	78	dev_err(&info->client->dev, "register read failed\n");
	79	return ret;
	80	}
	81
	82	*val = ret;
	83	return 0;
	84	}
	85
9b9ade6b	86	static inline int ds278x_read_reg16(struct ds278x_info *info, int reg_msb,
bfdb46ce RM	87	s16 *val)
	88	{
	89	int ret;
	90
8511748b	91	ret = i2c_smbus_read_word_data(info->client, reg_msb);
bfdb46ce RM	92	if (ret < 0) {
	93	dev_err(&info->client->dev, "register read failed\n");
	94	return ret;
	95	}
	96
8511748b	97	*val = swab16(ret);
bfdb46ce RM	98	return 0;
	99	}
	100
9b9ade6b	101	static int ds278x_get_temp(struct ds278x_info info, int temp)
bfdb46ce RM	102	{
	103	s16 raw;
	104	int err;
	105
	106	/*
	107	* Temperature is measured in units of 0.125 degrees celcius, the
	108	* power_supply class measures temperature in tenths of degrees
	109	* celsius. The temperature value is stored as a 10 bit number, plus
	110	* sign in the upper bits of a 16 bit register.
	111	*/
9b9ade6b	112	err = ds278x_read_reg16(info, DS278x_REG_TEMP_MSB, &raw);
bfdb46ce RM	113	if (err)
	114	return err;
	115	temp = ((raw / 32) 125) / 100;
	116	return 0;
	117	}
	118
9b9ade6b	119	static int ds2782_get_current(struct ds278x_info info, int current_uA)
bfdb46ce RM	120	{
	121	int sense_res;
	122	int err;
	123	u8 sense_res_raw;
	124	s16 raw;
	125
	126	/*
	127	* The units of measurement for current are dependent on the value of
	128	* the sense resistor.
	129	*/
9b9ade6b	130	err = ds278x_read_reg(info, DS2782_REG_RSNSP, &sense_res_raw);
bfdb46ce RM	131	if (err)
	132	return err;
	133	if (sense_res_raw == 0) {
	134	dev_err(&info->client->dev, "sense resistor value is 0\n");
	135	return -ENXIO;
	136	}
	137	sense_res = 1000 / sense_res_raw;
	138
	139	dev_dbg(&info->client->dev, "sense resistor = %d milli-ohms\n",
	140	sense_res);
9b9ade6b	141	err = ds278x_read_reg16(info, DS278x_REG_CURRENT_MSB, &raw);
bfdb46ce RM	142	if (err)
	143	return err;
	144	current_uA = raw (DS2782_CURRENT_UNITS / sense_res);
	145	return 0;
	146	}
	147
353f867b	148	static int ds2782_get_voltage(struct ds278x_info info, int voltage_uV)
bfdb46ce RM	149	{
	150	s16 raw;
	151	int err;
	152
	153	/*
	154	* Voltage is measured in units of 4.88mV. The voltage is stored as
	155	* a 10-bit number plus sign, in the upper bits of a 16-bit register
	156	*/
9b9ade6b	157	err = ds278x_read_reg16(info, DS278x_REG_VOLT_MSB, &raw);
bfdb46ce RM	158	if (err)
bfdb46ce RM	159	return err;
353f867b	160	voltage_uV = (raw / 32) 4800;
bfdb46ce RM	161	return 0;
	162	}
	163
9b9ade6b	164	static int ds2782_get_capacity(struct ds278x_info info, int capacity)
bfdb46ce RM	165	{
	166	int err;
	167	u8 raw;
	168
9b9ade6b	169	err = ds278x_read_reg(info, DS2782_REG_RARC, &raw);
bfdb46ce RM	170	if (err)
	171	return err;
	172	*capacity = raw;
2d31757c	173	return 0;
bfdb46ce RM	174	}
bfdb46ce RM	175
9b9ade6b YV	176	static int ds2786_get_current(struct ds278x_info info, int current_uA)
	177	{
	178	int err;
	179	s16 raw;
	180
	181	err = ds278x_read_reg16(info, DS278x_REG_CURRENT_MSB, &raw);
	182	if (err)
	183	return err;
	184	current_uA = (raw / 16) (DS2786_CURRENT_UNITS / info->rsns);
	185	return 0;
	186	}
	187
353f867b	188	static int ds2786_get_voltage(struct ds278x_info info, int voltage_uV)
9b9ade6b YV	189	{
	190	s16 raw;
	191	int err;
	192
	193	/*
	194	* Voltage is measured in units of 1.22mV. The voltage is stored as
	195	* a 10-bit number plus sign, in the upper bits of a 16-bit register
	196	*/
	197	err = ds278x_read_reg16(info, DS278x_REG_VOLT_MSB, &raw);
	198	if (err)
	199	return err;
353f867b	200	voltage_uV = (raw / 8) 1220;
9b9ade6b YV	201	return 0;
	202	}
	203
	204	static int ds2786_get_capacity(struct ds278x_info info, int capacity)
	205	{
	206	int err;
	207	u8 raw;
	208
	209	err = ds278x_read_reg(info, DS2786_REG_RARC, &raw);
	210	if (err)
	211	return err;
	212	/* Relative capacity is displayed with resolution 0.5 % */
	213	*capacity = raw/2 ;
	214	return 0;
	215	}
	216
	217	static int ds278x_get_status(struct ds278x_info info, int status)
bfdb46ce RM	218	{
	219	int err;
	220	int current_uA;
	221	int capacity;
	222
eb9650d6	223	err = info->ops->get_battery_current(info, &current_uA);
bfdb46ce RM	224	if (err)
	225	return err;
	226
eb9650d6	227	err = info->ops->get_battery_capacity(info, &capacity);
bfdb46ce RM	228	if (err)
	229	return err;
	230
7cee9aef ER	231	info->capacity = capacity;
7cee9aef ER	232
bfdb46ce RM	233	if (capacity == 100)
	234	*status = POWER_SUPPLY_STATUS_FULL;
	235	else if (current_uA == 0)
	236	*status = POWER_SUPPLY_STATUS_NOT_CHARGING;
	237	else if (current_uA < 0)
	238	*status = POWER_SUPPLY_STATUS_DISCHARGING;
	239	else
	240	*status = POWER_SUPPLY_STATUS_CHARGING;
	241
	242	return 0;
	243	}
	244
9b9ade6b	245	static int ds278x_battery_get_property(struct power_supply *psy,
bfdb46ce RM	246	enum power_supply_property prop,
	247	union power_supply_propval *val)
	248	{
9b9ade6b	249	struct ds278x_info *info = to_ds278x_info(psy);
bfdb46ce RM	250	int ret;
	251
	252	switch (prop) {
	253	case POWER_SUPPLY_PROP_STATUS:
9b9ade6b	254	ret = ds278x_get_status(info, &val->intval);
bfdb46ce RM	255	break;
	256
	257	case POWER_SUPPLY_PROP_CAPACITY:
eb9650d6	258	ret = info->ops->get_battery_capacity(info, &val->intval);
bfdb46ce RM	259	break;
	260
	261	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
eb9650d6	262	ret = info->ops->get_battery_voltage(info, &val->intval);
bfdb46ce RM	263	break;
	264
	265	case POWER_SUPPLY_PROP_CURRENT_NOW:
eb9650d6	266	ret = info->ops->get_battery_current(info, &val->intval);
bfdb46ce RM	267	break;
	268
	269	case POWER_SUPPLY_PROP_TEMP:
9b9ade6b	270	ret = ds278x_get_temp(info, &val->intval);
bfdb46ce RM	271	break;
	272
	273	default:
	274	ret = -EINVAL;
	275	}
	276
	277	return ret;
	278	}
	279
7cee9aef ER	280	static void ds278x_bat_update(struct ds278x_info *info)
	281	{
	282	int old_status = info->status;
	283	int old_capacity = info->capacity;
	284
	285	ds278x_get_status(info, &info->status);
	286
	287	if ((old_status != info->status) \|\| (old_capacity != info->capacity))
	288	power_supply_changed(&info->battery);
	289	}
	290
	291	static void ds278x_bat_work(struct work_struct *work)
	292	{
	293	struct ds278x_info *info;
	294
	295	info = container_of(work, struct ds278x_info, bat_work.work);
	296	ds278x_bat_update(info);
	297
	298	schedule_delayed_work(&info->bat_work, DS278x_DELAY);
	299	}
	300
9b9ade6b	301	static enum power_supply_property ds278x_battery_props[] = {
bfdb46ce RM	302	POWER_SUPPLY_PROP_STATUS,
	303	POWER_SUPPLY_PROP_CAPACITY,
	304	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	305	POWER_SUPPLY_PROP_CURRENT_NOW,
	306	POWER_SUPPLY_PROP_TEMP,
	307	};
	308
9b9ade6b	309	static void ds278x_power_supply_init(struct power_supply *battery)
bfdb46ce RM	310	{
bfdb46ce RM	311	battery->type = POWER_SUPPLY_TYPE_BATTERY;
9b9ade6b YV	312	battery->properties = ds278x_battery_props;
	313	battery->num_properties = ARRAY_SIZE(ds278x_battery_props);
	314	battery->get_property = ds278x_battery_get_property;
bfdb46ce RM	315	battery->external_power_changed = NULL;
	316	}
	317
9b9ade6b	318	static int ds278x_battery_remove(struct i2c_client *client)
bfdb46ce	319	{
9b9ade6b	320	struct ds278x_info *info = i2c_get_clientdata(client);
bfdb46ce RM	321
	322	power_supply_unregister(&info->battery);
	323	kfree(info->battery.name);
	324
	325	mutex_lock(&battery_lock);
	326	idr_remove(&battery_id, info->id);
	327	mutex_unlock(&battery_lock);
	328
7cee9aef ER	329	cancel_delayed_work(&info->bat_work);
7cee9aef ER	330
bfdb46ce RM	331	kfree(info);
	332	return 0;
	333	}
	334
7cee9aef ER	335	#ifdef CONFIG_PM
	336
	337	static int ds278x_suspend(struct i2c_client *client,
	338	pm_message_t state)
	339	{
	340	struct ds278x_info *info = i2c_get_clientdata(client);
	341
	342	cancel_delayed_work(&info->bat_work);
	343	return 0;
	344	}
	345
	346	static int ds278x_resume(struct i2c_client *client)
	347	{
	348	struct ds278x_info *info = i2c_get_clientdata(client);
	349
	350	schedule_delayed_work(&info->bat_work, DS278x_DELAY);
	351	return 0;
	352	}
	353
	354	#else
	355
	356	#define ds278x_suspend NULL
	357	#define ds278x_resume NULL
	358
	359	#endif /* CONFIG_PM */
	360
	361
ab6cc8f9 AV	362	enum ds278x_num_id {
	363	DS2782 = 0,
	364	DS2786,
	365	};
	366
9b9ade6b	367	static struct ds278x_battery_ops ds278x_ops[] = {
ab6cc8f9	368	[DS2782] = {
eb9650d6 PH	369	.get_battery_current = ds2782_get_current,
	370	.get_battery_voltage = ds2782_get_voltage,
	371	.get_battery_capacity = ds2782_get_capacity,
9b9ade6b	372	},
ab6cc8f9	373	[DS2786] = {
eb9650d6 PH	374	.get_battery_current = ds2786_get_current,
	375	.get_battery_voltage = ds2786_get_voltage,
	376	.get_battery_capacity = ds2786_get_capacity,
9b9ade6b YV	377	}
	378	};
	379
	380	static int ds278x_battery_probe(struct i2c_client *client,
bfdb46ce RM	381	const struct i2c_device_id *id)
bfdb46ce RM	382	{
9b9ade6b YV	383	struct ds278x_platform_data *pdata = client->dev.platform_data;
9b9ade6b YV	384	struct ds278x_info *info;
bfdb46ce RM	385	int ret;
	386	int num;
	387
9b9ade6b YV	388	/*
	389	* ds2786 should have the sense resistor value set
	390	* in the platform data
	391	*/
ab6cc8f9	392	if (id->driver_data == DS2786 && !pdata) {
9b9ade6b YV	393	dev_err(&client->dev, "missing platform data for ds2786\n");
	394	return -EINVAL;
	395	}
	396
bfdb46ce RM	397	/* Get an ID for this battery */
	398	ret = idr_pre_get(&battery_id, GFP_KERNEL);
	399	if (ret == 0) {
	400	ret = -ENOMEM;
	401	goto fail_id;
	402	}
	403
	404	mutex_lock(&battery_lock);
	405	ret = idr_get_new(&battery_id, client, &num);
	406	mutex_unlock(&battery_lock);
	407	if (ret < 0)
	408	goto fail_id;
	409
	410	info = kzalloc(sizeof(*info), GFP_KERNEL);
	411	if (!info) {
	412	ret = -ENOMEM;
	413	goto fail_info;
	414	}
	415
9b9ade6b	416	info->battery.name = kasprintf(GFP_KERNEL, "%s-%d", client->name, num);
bfdb46ce RM	417	if (!info->battery.name) {
	418	ret = -ENOMEM;
	419	goto fail_name;
	420	}
	421
ab6cc8f9	422	if (id->driver_data == DS2786)
9b9ade6b YV	423	info->rsns = pdata->rsns;
9b9ade6b YV	424
bfdb46ce RM	425	i2c_set_clientdata(client, info);
bfdb46ce RM	426	info->client = client;
9b9ade6b YV	427	info->id = num;
	428	info->ops = &ds278x_ops[id->driver_data];
	429	ds278x_power_supply_init(&info->battery);
bfdb46ce	430
7cee9aef ER	431	info->capacity = 100;
	432	info->status = POWER_SUPPLY_STATUS_FULL;
	433
	434	INIT_DELAYED_WORK(&info->bat_work, ds278x_bat_work);
	435
bfdb46ce RM	436	ret = power_supply_register(&client->dev, &info->battery);
	437	if (ret) {
	438	dev_err(&client->dev, "failed to register battery\n");
	439	goto fail_register;
7cee9aef ER	440	} else {
7cee9aef ER	441	schedule_delayed_work(&info->bat_work, DS278x_DELAY);
bfdb46ce RM	442	}
	443
	444	return 0;
	445
	446	fail_register:
	447	kfree(info->battery.name);
	448	fail_name:
bfdb46ce RM	449	kfree(info);
	450	fail_info:
	451	mutex_lock(&battery_lock);
	452	idr_remove(&battery_id, num);
	453	mutex_unlock(&battery_lock);
	454	fail_id:
	455	return ret;
	456	}
	457
9b9ade6b	458	static const struct i2c_device_id ds278x_id[] = {
ab6cc8f9 AV	459	{"ds2782", DS2782},
ab6cc8f9 AV	460	{"ds2786", DS2786},
bfdb46ce RM	461	{},
bfdb46ce RM	462	};
84ab16f5	463	MODULE_DEVICE_TABLE(i2c, ds278x_id);
bfdb46ce	464
9b9ade6b	465	static struct i2c_driver ds278x_battery_driver = {
bfdb46ce RM	466	.driver = {
	467	.name = "ds2782-battery",
	468	},
9b9ade6b YV	469	.probe = ds278x_battery_probe,
9b9ade6b YV	470	.remove = ds278x_battery_remove,
7cee9aef ER	471	.suspend = ds278x_suspend,
7cee9aef ER	472	.resume = ds278x_resume,
9b9ade6b	473	.id_table = ds278x_id,
bfdb46ce	474	};
5ff92e7a	475	module_i2c_driver(ds278x_battery_driver);
bfdb46ce	476
1c5454ee	477	MODULE_AUTHOR("Ryan Mallon");
bfdb46ce RM	478	MODULE_DESCRIPTION("Maxim/Dallas DS2782 Stand-Alone Fuel Gauage IC driver");
bfdb46ce RM	479	MODULE_LICENSE("GPL");