[deliverable/linux.git] / drivers / power / bq27x00_battery.c

/*
 * BQ27x00 battery driver
 *
 * Copyright (C) 2008 Rodolfo Giometti <giometti@linux.it>
 * Copyright (C) 2008 Eurotech S.p.A. <info@eurotech.it>
 * Copyright (C) 2010-2011 Lars-Peter Clausen <lars@metafoo.de>
 *
 * Based on a previous work by Copyright (C) 2008 Texas Instruments, Inc.
 *
 * This package 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.
 *
 * THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 */
#include <linux/module.h>
#include <linux/param.h>
#include <linux/jiffies.h>
#include <linux/workqueue.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/idr.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <asm/unaligned.h>

#include <linux/power/bq27x00_battery.h>

#define DRIVER_VERSION			"1.1.0"

#define BQ27x00_REG_TEMP		0x06
#define BQ27x00_REG_VOLT		0x08
#define BQ27x00_REG_AI			0x14
#define BQ27x00_REG_FLAGS		0x0A
#define BQ27x00_REG_TTE			0x16
#define BQ27x00_REG_TTF			0x18
#define BQ27x00_REG_TTECP		0x26

#define BQ27000_REG_RSOC		0x0B /* Relative State-of-Charge */
#define BQ27000_FLAG_CHGS		BIT(7)

#define BQ27500_REG_SOC			0x2c
#define BQ27500_FLAG_DSC		BIT(0)
#define BQ27500_FLAG_FC			BIT(9)

#define BQ27000_RS			20 /* Resistor sense */

struct bq27x00_device_info;
struct bq27x00_access_methods {
	int (*read)(struct bq27x00_device_info *di, u8 reg, bool single);
};

enum bq27x00_chip { BQ27000, BQ27500 };

struct bq27x00_reg_cache {
	int temperature;
	int time_to_empty;
	int time_to_empty_avg;
	int time_to_full;
	int capacity;
	int flags;

	int current_now;
};

struct bq27x00_device_info {
	struct device 		*dev;
	int			id;
	enum bq27x00_chip	chip;

	struct bq27x00_reg_cache cache;
	unsigned long last_update;

	struct power_supply	bat;

	struct bq27x00_access_methods bus;
};

static enum power_supply_property bq27x00_battery_props[] = {
	POWER_SUPPLY_PROP_STATUS,
	POWER_SUPPLY_PROP_PRESENT,
	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	POWER_SUPPLY_PROP_CURRENT_NOW,
	POWER_SUPPLY_PROP_CAPACITY,
	POWER_SUPPLY_PROP_TEMP,
	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
	POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
	POWER_SUPPLY_PROP_TECHNOLOGY,
};

/*
 * Common code for BQ27x00 devices
 */

static inline int bq27x00_read(struct bq27x00_device_info *di, u8 reg,
		bool single)
{
	return di->bus.read(di, reg, single);
}

/*
 * Return the battery Relative State-of-Charge
 * Or < 0 if something fails.
 */
static int bq27x00_battery_read_rsoc(struct bq27x00_device_info *di)
{
	int rsoc;

	if (di->chip == BQ27500)
		rsoc = bq27x00_read(di, BQ27500_REG_SOC, false);
	else
		rsoc = bq27x00_read(di, BQ27000_REG_RSOC, true);

	if (rsoc < 0)
		dev_err(di->dev, "error reading relative State-of-Charge\n");

	return rsoc;
}

/*
 * Read a time register.
 * Return < 0 if something fails.
 */
static int bq27x00_battery_read_time(struct bq27x00_device_info *di, u8 reg)
{
	int tval;

	tval = bq27x00_read(di, reg, false);
	if (tval < 0) {
		dev_err(di->dev, "error reading register %02x: %d\n", reg, tval);
		return tval;
	}

	if (tval == 65535)
		return -ENODATA;

	return tval * 60;
}

static void bq27x00_update(struct bq27x00_device_info *di)
{
	struct bq27x00_reg_cache cache = {0, };
	bool is_bq27500 = di->chip == BQ27500;

	cache.flags = bq27x00_read(di, BQ27x00_REG_FLAGS, is_bq27500);
	if (cache.flags >= 0) {
		cache.capacity = bq27x00_battery_read_rsoc(di);
		cache.temperature = bq27x00_read(di, BQ27x00_REG_TEMP, false);
		cache.time_to_empty = bq27x00_battery_read_time(di, BQ27x00_REG_TTE);
		cache.time_to_empty_avg = bq27x00_battery_read_time(di, BQ27x00_REG_TTECP);
		cache.time_to_full = bq27x00_battery_read_time(di, BQ27x00_REG_TTF);

		if (!is_bq27500)
			cache.current_now = bq27x00_read(di, BQ27x00_REG_AI, false);
	}

	/* Ignore current_now which is a snapshot of the current battery state
	 * and is likely to be different even between two consecutive reads */
	if (memcmp(&di->cache, &cache, sizeof(cache) - sizeof(int)) != 0) {
		di->cache = cache;
		power_supply_changed(&di->bat);
	}

	di->last_update = jiffies;
}

/*
 * Return the battery temperature in tenths of degree Celsius
 * Or < 0 if something fails.
 */
static int bq27x00_battery_temperature(struct bq27x00_device_info *di,
	union power_supply_propval *val)
{
	if (di->cache.temperature < 0)
		return di->cache.temperature;

	if (di->chip == BQ27500)
		val->intval = di->cache.temperature - 2731;
	else
		val->intval = ((di->cache.temperature * 5) - 5463) / 2;

	return 0;
}

/*
 * Return the battery average current
 * Note that current can be negative signed as well
 * Or 0 if something fails.
 */
static int bq27x00_battery_current(struct bq27x00_device_info *di,
	union power_supply_propval *val)
{
	int curr;

	if (di->chip == BQ27500)
	    curr = bq27x00_read(di, BQ27x00_REG_AI, false);
	else
	    curr = di->cache.current_now;

	if (curr < 0)
		return curr;

	if (di->chip == BQ27500) {
		/* bq27500 returns signed value */
		val->intval = (int)((s16)curr) * 1000;
	} else {
		if (di->cache.flags & BQ27000_FLAG_CHGS) {
			dev_dbg(di->dev, "negative current!\n");
			curr = -curr;
		}

		val->intval = curr * 3570 / BQ27000_RS;
	}

	return 0;
}

static int bq27x00_battery_status(struct bq27x00_device_info *di,
	union power_supply_propval *val)
{
	int status;

	if (di->chip == BQ27500) {
		if (di->cache.flags & BQ27500_FLAG_FC)
			status = POWER_SUPPLY_STATUS_FULL;
		else if (di->cache.flags & BQ27500_FLAG_DSC)
			status = POWER_SUPPLY_STATUS_DISCHARGING;
		else
			status = POWER_SUPPLY_STATUS_CHARGING;
	} else {
		if (di->cache.flags & BQ27000_FLAG_CHGS)
			status = POWER_SUPPLY_STATUS_CHARGING;
		else
			status = POWER_SUPPLY_STATUS_DISCHARGING;
	}

	val->intval = status;

	return 0;
}

/*
 * Return the battery Voltage in milivolts
 * Or < 0 if something fails.
 */
static int bq27x00_battery_voltage(struct bq27x00_device_info *di,
	union power_supply_propval *val)
{
	int volt;

	volt = bq27x00_read(di, BQ27x00_REG_VOLT, false);
	if (volt < 0)
		return volt;

	val->intval = volt * 1000;

	return 0;
}

static int bq27x00_simple_value(int value,
	union power_supply_propval *val)
{
	if (value < 0)
		return value;

	val->intval = value;

	return 0;
}

#define to_bq27x00_device_info(x) container_of((x), \
				struct bq27x00_device_info, bat);

static int bq27x00_battery_get_property(struct power_supply *psy,
					enum power_supply_property psp,
					union power_supply_propval *val)
{
	int ret = 0;
	struct bq27x00_device_info *di = to_bq27x00_device_info(psy);

	if (time_is_before_jiffies(di->last_update + 5 * HZ))
		bq27x00_update(di);

	if (psp != POWER_SUPPLY_PROP_PRESENT && di->cache.flags < 0)
		return -ENODEV;

	switch (psp) {
	case POWER_SUPPLY_PROP_STATUS:
		ret = bq27x00_battery_status(di, val);
		break;
	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
		ret = bq27x00_battery_voltage(di, val);
		break;
	case POWER_SUPPLY_PROP_PRESENT:
		val->intval = di->cache.flags < 0 ? 0 : 1;
		break;
	case POWER_SUPPLY_PROP_CURRENT_NOW:
		ret = bq27x00_battery_current(di, val);
		break;
	case POWER_SUPPLY_PROP_CAPACITY:
		ret = bq27x00_simple_value(di->cache.capacity, val);
		break;
	case POWER_SUPPLY_PROP_TEMP:
		ret = bq27x00_battery_temperature(di, val);
		break;
	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
		ret = bq27x00_simple_value(di->cache.time_to_empty, val);
		break;
	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
		ret = bq27x00_simple_value(di->cache.time_to_empty_avg, val);
		break;
	case POWER_SUPPLY_PROP_TIME_TO_FULL_NOW:
		ret = bq27x00_simple_value(di->cache.time_to_full, val);
		break;
	case POWER_SUPPLY_PROP_TECHNOLOGY:
		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
		break;
	default:
		return -EINVAL;
	}

	return ret;
}

static int bq27x00_powersupply_init(struct bq27x00_device_info *di)
{
	int ret;

	di->bat.type = POWER_SUPPLY_TYPE_BATTERY;
	di->bat.properties = bq27x00_battery_props;
	di->bat.num_properties = ARRAY_SIZE(bq27x00_battery_props);
	di->bat.get_property = bq27x00_battery_get_property;
	di->bat.external_power_changed = NULL;

	ret = power_supply_register(di->dev, &di->bat);
	if (ret) {
		dev_err(di->dev, "failed to register battery: %d\n", ret);
		return ret;
	}

	dev_info(di->dev, "support ver. %s enabled\n", DRIVER_VERSION);

	bq27x00_update(di);

	return 0;
}


/* i2c specific code */
#ifdef CONFIG_BATTERY_BQ27X00_I2C

/* If the system has several batteries we need a different name for each
 * of them...
 */
static DEFINE_IDR(battery_id);
static DEFINE_MUTEX(battery_mutex);

static int bq27x00_read_i2c(struct bq27x00_device_info *di, u8 reg, bool single)
{
	struct i2c_client *client = to_i2c_client(di->dev);
	struct i2c_msg msg[1];
	unsigned char data[2];
	int ret;

	if (!client->adapter)
		return -ENODEV;

	msg->addr = client->addr;
	msg->flags = 0;
	msg->len = 1;
	msg->buf = data;

	data[0] = reg;
	ret = i2c_transfer(client->adapter, msg, 1);

	if (ret >= 0) {
		if (!single)
			msg->len = 2;
		else
			msg->len = 1;

		msg->flags = I2C_M_RD;
		ret = i2c_transfer(client->adapter, msg, 1);
		if (ret >= 0) {
			if (!single)
				ret = get_unaligned_le16(data);
			else
				ret = data[0];
		}
	}
	return ret;
}

static int bq27x00_battery_probe(struct i2c_client *client,
				 const struct i2c_device_id *id)
{
	char *name;
	struct bq27x00_device_info *di;
	int num;
	int retval = 0;

	/* Get new ID for the new battery device */
	retval = idr_pre_get(&battery_id, GFP_KERNEL);
	if (retval == 0)
		return -ENOMEM;
	mutex_lock(&battery_mutex);
	retval = idr_get_new(&battery_id, client, &num);
	mutex_unlock(&battery_mutex);
	if (retval < 0)
		return retval;

	name = kasprintf(GFP_KERNEL, "%s-%d", id->name, num);
	if (!name) {
		dev_err(&client->dev, "failed to allocate device name\n");
		retval = -ENOMEM;
		goto batt_failed_1;
	}

	di = kzalloc(sizeof(*di), GFP_KERNEL);
	if (!di) {
		dev_err(&client->dev, "failed to allocate device info data\n");
		retval = -ENOMEM;
		goto batt_failed_2;
	}

	di->id = num;
	di->dev = &client->dev;
	di->chip = id->driver_data;
	di->bat.name = name;
	di->bus.read = &bq27x00_read_i2c;

	if (bq27x00_powersupply_init(di))
		goto batt_failed_3;

	i2c_set_clientdata(client, di);

	return 0;

batt_failed_3:
	kfree(di);
batt_failed_2:
	kfree(name);
batt_failed_1:
	mutex_lock(&battery_mutex);
	idr_remove(&battery_id, num);
	mutex_unlock(&battery_mutex);

	return retval;
}

static int bq27x00_battery_remove(struct i2c_client *client)
{
	struct bq27x00_device_info *di = i2c_get_clientdata(client);

	power_supply_unregister(&di->bat);

	kfree(di->bat.name);

	mutex_lock(&battery_mutex);
	idr_remove(&battery_id, di->id);
	mutex_unlock(&battery_mutex);

	kfree(di);

	return 0;
}

static const struct i2c_device_id bq27x00_id[] = {
	{ "bq27200", BQ27000 },	/* bq27200 is same as bq27000, but with i2c */
	{ "bq27500", BQ27500 },
	{},
};

static struct i2c_driver bq27x00_battery_driver = {
	.driver = {
		.name = "bq27x00-battery",
	},
	.probe = bq27x00_battery_probe,
	.remove = bq27x00_battery_remove,
	.id_table = bq27x00_id,
};

static inline int bq27x00_battery_i2c_init(void)
{
	int ret = i2c_add_driver(&bq27x00_battery_driver);
	if (ret)
		printk(KERN_ERR "Unable to register BQ27x00 i2c driver\n");

	return ret;
}

static inline void bq27x00_battery_i2c_exit(void)
{
	i2c_del_driver(&bq27x00_battery_driver);
}

#else

static inline int bq27x00_battery_i2c_init(void) { return 0; }
static inline void bq27x00_battery_i2c_exit(void) {};

#endif

/* platform specific code */
#ifdef CONFIG_BATTERY_BQ27X00_PLATFORM

static int bq27000_read_platform(struct bq27x00_device_info *di, u8 reg,
			bool single)
{
	struct device *dev = di->dev;
	struct bq27000_platform_data *pdata = dev->platform_data;
	unsigned int timeout = 3;
	int upper, lower;
	int temp;

	if (!single) {
		/* Make sure the value has not changed in between reading the
		 * lower and the upper part */
		upper = pdata->read(dev, reg + 1);
		do {
			temp = upper;
			if (upper < 0)
				return upper;

			lower = pdata->read(dev, reg);
			if (lower < 0)
				return lower;

			upper = pdata->read(dev, reg + 1);
		} while (temp != upper && --timeout);

		if (timeout == 0)
			return -EIO;

		return (upper << 8) | lower;
	}

	return pdata->read(dev, reg);
}

static int __devinit bq27000_battery_probe(struct platform_device *pdev)
{
	struct bq27x00_device_info *di;
	struct bq27000_platform_data *pdata = pdev->dev.platform_data;
	int ret;

	if (!pdata) {
		dev_err(&pdev->dev, "no platform_data supplied\n");
		return -EINVAL;
	}

	if (!pdata->read) {
		dev_err(&pdev->dev, "no hdq read callback supplied\n");
		return -EINVAL;
	}

	di = kzalloc(sizeof(*di), GFP_KERNEL);
	if (!di) {
		dev_err(&pdev->dev, "failed to allocate device info data\n");
		return -ENOMEM;
	}

	platform_set_drvdata(pdev, di);

	di->dev = &pdev->dev;
	di->chip = BQ27000;

	di->bat.name = pdata->name ?: dev_name(&pdev->dev);
	di->bus.read = &bq27000_read_platform;

	ret = bq27x00_powersupply_init(di);
	if (ret)
		goto err_free;

	return 0;

err_free:
	platform_set_drvdata(pdev, NULL);
	kfree(di);

	return ret;
}

static int __devexit bq27000_battery_remove(struct platform_device *pdev)
{
	struct bq27x00_device_info *di = platform_get_drvdata(pdev);

	power_supply_unregister(&di->bat);
	platform_set_drvdata(pdev, NULL);
	kfree(di);

	return 0;
}

static struct platform_driver bq27000_battery_driver = {
	.probe	= bq27000_battery_probe,
	.remove = __devexit_p(bq27000_battery_remove),
	.driver = {
		.name = "bq27000-battery",
		.owner = THIS_MODULE,
	},
};

static inline int bq27x00_battery_platform_init(void)
{
	int ret = platform_driver_register(&bq27000_battery_driver);
	if (ret)
		printk(KERN_ERR "Unable to register BQ27000 platform driver\n");

	return ret;
}

static inline void bq27x00_battery_platform_exit(void)
{
	platform_driver_unregister(&bq27000_battery_driver);
}

#else

static inline int bq27x00_battery_platform_init(void) { return 0; }
static inline void bq27x00_battery_platform_exit(void) {};

#endif

/*
 * Module stuff
 */

static int __init bq27x00_battery_init(void)
{
	int ret;

	ret = bq27x00_battery_i2c_init();
	if (ret)
		return ret;

	ret = bq27x00_battery_platform_init();
	if (ret)
		bq27x00_battery_i2c_exit();

	return ret;
}
module_init(bq27x00_battery_init);

static void __exit bq27x00_battery_exit(void)
{
	bq27x00_battery_platform_exit();
	bq27x00_battery_i2c_exit();
}
module_exit(bq27x00_battery_exit);

MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
MODULE_DESCRIPTION("BQ27x00 battery monitor driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
b996ad0e RG	1	/*
	2	* BQ27x00 battery driver
	3	*
	4	* Copyright (C) 2008 Rodolfo Giometti <giometti@linux.it>
	5	* Copyright (C) 2008 Eurotech S.p.A. <info@eurotech.it>
7fb7ba58	6	* Copyright (C) 2010-2011 Lars-Peter Clausen <lars@metafoo.de>
b996ad0e RG	7	*
	8	* Based on a previous work by Copyright (C) 2008 Texas Instruments, Inc.
	9	*
	10	* This package is free software; you can redistribute it and/or modify
	11	* it under the terms of the GNU General Public License version 2 as
	12	* published by the Free Software Foundation.
	13	*
	14	* THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
	15	* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
	16	* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
	17	*
	18	*/
	19	#include <linux/module.h>
	20	#include <linux/param.h>
	21	#include <linux/jiffies.h>
	22	#include <linux/workqueue.h>
	23	#include <linux/delay.h>
	24	#include <linux/platform_device.h>
	25	#include <linux/power_supply.h>
	26	#include <linux/idr.h>
b996ad0e	27	#include <linux/i2c.h>
5a0e3ad6	28	#include <linux/slab.h>
8aef7e8f	29	#include <asm/unaligned.h>
b996ad0e	30
7fb7ba58 LPC	31	#include <linux/power/bq27x00_battery.h>
7fb7ba58 LPC	32
e20908d9	33	#define DRIVER_VERSION "1.1.0"
b996ad0e RG	34
	35	#define BQ27x00_REG_TEMP 0x06
	36	#define BQ27x00_REG_VOLT 0x08
b996ad0e RG	37	#define BQ27x00_REG_AI 0x14
b996ad0e RG	38	#define BQ27x00_REG_FLAGS 0x0A
4e924a81 GI	39	#define BQ27x00_REG_TTE 0x16
	40	#define BQ27x00_REG_TTF 0x18
	41	#define BQ27x00_REG_TTECP 0x26
b996ad0e	42
e20908d9	43	#define BQ27000_REG_RSOC 0x0B /* Relative State-of-Charge */
4e924a81	44	#define BQ27000_FLAG_CHGS BIT(7)
e20908d9 GI	45
e20908d9 GI	46	#define BQ27500_REG_SOC 0x2c
4e924a81 GI	47	#define BQ27500_FLAG_DSC BIT(0)
4e924a81 GI	48	#define BQ27500_FLAG_FC BIT(9)
e20908d9	49
a2e5118c PR	50	#define BQ27000_RS 20 /* Resistor sense */
a2e5118c PR	51
b996ad0e RG	52	struct bq27x00_device_info;
b996ad0e RG	53	struct bq27x00_access_methods {
297a533b	54	int (read)(struct bq27x00_device_info di, u8 reg, bool single);
b996ad0e RG	55	};
b996ad0e RG	56
e20908d9 GI	57	enum bq27x00_chip { BQ27000, BQ27500 };
e20908d9 GI	58
297a533b LPC	59	struct bq27x00_reg_cache {
	60	int temperature;
	61	int time_to_empty;
	62	int time_to_empty_avg;
	63	int time_to_full;
	64	int capacity;
	65	int flags;
	66
	67	int current_now;
	68	};
	69
b996ad0e RG	70	struct bq27x00_device_info {
	71	struct device *dev;
	72	int id;
e20908d9	73	enum bq27x00_chip chip;
b996ad0e	74
297a533b LPC	75	struct bq27x00_reg_cache cache;
	76	unsigned long last_update;
	77
a40402ef LPC	78	struct power_supply bat;
	79
	80	struct bq27x00_access_methods bus;
b996ad0e RG	81	};
	82
	83	static enum power_supply_property bq27x00_battery_props[] = {
4e924a81	84	POWER_SUPPLY_PROP_STATUS,
b996ad0e RG	85	POWER_SUPPLY_PROP_PRESENT,
	86	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	87	POWER_SUPPLY_PROP_CURRENT_NOW,
	88	POWER_SUPPLY_PROP_CAPACITY,
	89	POWER_SUPPLY_PROP_TEMP,
4e924a81 GI	90	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
	91	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
	92	POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
5661f334	93	POWER_SUPPLY_PROP_TECHNOLOGY,
b996ad0e RG	94	};
	95
	96	/*
	97	* Common code for BQ27x00 devices
	98	*/
	99
a40402ef	100	static inline int bq27x00_read(struct bq27x00_device_info *di, u8 reg,
297a533b	101	bool single)
b996ad0e	102	{
297a533b	103	return di->bus.read(di, reg, single);
b996ad0e RG	104	}
	105
	106	/*
297a533b	107	* Return the battery Relative State-of-Charge
b996ad0e RG	108	* Or < 0 if something fails.
b996ad0e RG	109	*/
297a533b	110	static int bq27x00_battery_read_rsoc(struct bq27x00_device_info *di)
b996ad0e	111	{
297a533b	112	int rsoc;
b996ad0e	113
e20908d9	114	if (di->chip == BQ27500)
297a533b	115	rsoc = bq27x00_read(di, BQ27500_REG_SOC, false);
e20908d9	116	else
297a533b LPC	117	rsoc = bq27x00_read(di, BQ27000_REG_RSOC, true);
	118
	119	if (rsoc < 0)
	120	dev_err(di->dev, "error reading relative State-of-Charge\n");
	121
	122	return rsoc;
b996ad0e RG	123	}
	124
	125	/*
297a533b LPC	126	* Read a time register.
297a533b LPC	127	* Return < 0 if something fails.
b996ad0e	128	*/
297a533b	129	static int bq27x00_battery_read_time(struct bq27x00_device_info *di, u8 reg)
b996ad0e	130	{
297a533b	131	int tval;
b996ad0e	132
297a533b LPC	133	tval = bq27x00_read(di, reg, false);
	134	if (tval < 0) {
	135	dev_err(di->dev, "error reading register %02x: %d\n", reg, tval);
	136	return tval;
b996ad0e RG	137	}
b996ad0e RG	138
297a533b LPC	139	if (tval == 65535)
	140	return -ENODATA;
	141
	142	return tval * 60;
	143	}
	144
	145	static void bq27x00_update(struct bq27x00_device_info *di)
	146	{
	147	struct bq27x00_reg_cache cache = {0, };
	148	bool is_bq27500 = di->chip == BQ27500;
	149
	150	cache.flags = bq27x00_read(di, BQ27x00_REG_FLAGS, is_bq27500);
	151	if (cache.flags >= 0) {
	152	cache.capacity = bq27x00_battery_read_rsoc(di);
	153	cache.temperature = bq27x00_read(di, BQ27x00_REG_TEMP, false);
	154	cache.time_to_empty = bq27x00_battery_read_time(di, BQ27x00_REG_TTE);
	155	cache.time_to_empty_avg = bq27x00_battery_read_time(di, BQ27x00_REG_TTECP);
	156	cache.time_to_full = bq27x00_battery_read_time(di, BQ27x00_REG_TTF);
	157
	158	if (!is_bq27500)
	159	cache.current_now = bq27x00_read(di, BQ27x00_REG_AI, false);
	160	}
	161
	162	/* Ignore current_now which is a snapshot of the current battery state
	163	* and is likely to be different even between two consecutive reads */
	164	if (memcmp(&di->cache, &cache, sizeof(cache) - sizeof(int)) != 0) {
	165	di->cache = cache;
	166	power_supply_changed(&di->bat);
	167	}
	168
	169	di->last_update = jiffies;
	170	}
	171
	172	/*
	173	* Return the battery temperature in tenths of degree Celsius
	174	* Or < 0 if something fails.
	175	*/
	176	static int bq27x00_battery_temperature(struct bq27x00_device_info *di,
	177	union power_supply_propval *val)
	178	{
	179	if (di->cache.temperature < 0)
	180	return di->cache.temperature;
	181
	182	if (di->chip == BQ27500)
	183	val->intval = di->cache.temperature - 2731;
	184	else
	185	val->intval = ((di->cache.temperature * 5) - 5463) / 2;
	186
	187	return 0;
b996ad0e RG	188	}
	189
	190	/*
	191	* Return the battery average current
	192	* Note that current can be negative signed as well
	193	* Or 0 if something fails.
	194	*/
297a533b LPC	195	static int bq27x00_battery_current(struct bq27x00_device_info *di,
297a533b LPC	196	union power_supply_propval *val)
b996ad0e	197	{
297a533b	198	int curr;
b996ad0e	199
297a533b LPC	200	if (di->chip == BQ27500)
	201	curr = bq27x00_read(di, BQ27x00_REG_AI, false);
	202	else
	203	curr = di->cache.current_now;
	204
	205	if (curr < 0)
	206	return curr;
e20908d9 GI	207
	208	if (di->chip == BQ27500) {
	209	/* bq27500 returns signed value */
297a533b	210	val->intval = (int)((s16)curr) * 1000;
e20908d9	211	} else {
297a533b	212	if (di->cache.flags & BQ27000_FLAG_CHGS) {
e20908d9	213	dev_dbg(di->dev, "negative current!\n");
afbc74fd	214	curr = -curr;
e20908d9	215	}
b996ad0e	216
297a533b	217	val->intval = curr * 3570 / BQ27000_RS;
b996ad0e RG	218	}
b996ad0e RG	219
297a533b	220	return 0;
b996ad0e RG	221	}
b996ad0e RG	222
4e924a81	223	static int bq27x00_battery_status(struct bq27x00_device_info *di,
297a533b	224	union power_supply_propval *val)
4e924a81	225	{
4e924a81	226	int status;
4e924a81 GI	227
4e924a81 GI	228	if (di->chip == BQ27500) {
297a533b	229	if (di->cache.flags & BQ27500_FLAG_FC)
4e924a81	230	status = POWER_SUPPLY_STATUS_FULL;
297a533b	231	else if (di->cache.flags & BQ27500_FLAG_DSC)
4e924a81 GI	232	status = POWER_SUPPLY_STATUS_DISCHARGING;
	233	else
	234	status = POWER_SUPPLY_STATUS_CHARGING;
	235	} else {
297a533b	236	if (di->cache.flags & BQ27000_FLAG_CHGS)
4e924a81 GI	237	status = POWER_SUPPLY_STATUS_CHARGING;
	238	else
	239	status = POWER_SUPPLY_STATUS_DISCHARGING;
	240	}
	241
	242	val->intval = status;
297a533b	243
4e924a81 GI	244	return 0;
	245	}
	246
	247	/*
297a533b LPC	248	* Return the battery Voltage in milivolts
297a533b LPC	249	* Or < 0 if something fails.
4e924a81	250	*/
297a533b LPC	251	static int bq27x00_battery_voltage(struct bq27x00_device_info *di,
297a533b LPC	252	union power_supply_propval *val)
4e924a81	253	{
297a533b	254	int volt;
4e924a81	255
297a533b LPC	256	volt = bq27x00_read(di, BQ27x00_REG_VOLT, false);
	257	if (volt < 0)
	258	return volt;
4e924a81	259
297a533b LPC	260	val->intval = volt * 1000;
	261
	262	return 0;
	263	}
	264
	265	static int bq27x00_simple_value(int value,
	266	union power_supply_propval *val)
	267	{
	268	if (value < 0)
	269	return value;
	270
	271	val->intval = value;
4e924a81	272
4e924a81 GI	273	return 0;
	274	}
	275
b996ad0e RG	276	#define to_bq27x00_device_info(x) container_of((x), \
	277	struct bq27x00_device_info, bat);
	278
	279	static int bq27x00_battery_get_property(struct power_supply *psy,
	280	enum power_supply_property psp,
	281	union power_supply_propval *val)
	282	{
4e924a81	283	int ret = 0;
b996ad0e	284	struct bq27x00_device_info *di = to_bq27x00_device_info(psy);
3413b4ea	285
297a533b LPC	286	if (time_is_before_jiffies(di->last_update + 5 * HZ))
	287	bq27x00_update(di);
	288
	289	if (psp != POWER_SUPPLY_PROP_PRESENT && di->cache.flags < 0)
3413b4ea	290	return -ENODEV;
b996ad0e RG	291
b996ad0e RG	292	switch (psp) {
4e924a81 GI	293	case POWER_SUPPLY_PROP_STATUS:
	294	ret = bq27x00_battery_status(di, val);
	295	break;
b996ad0e	296	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
297a533b	297	ret = bq27x00_battery_voltage(di, val);
3413b4ea	298	break;
b996ad0e	299	case POWER_SUPPLY_PROP_PRESENT:
297a533b	300	val->intval = di->cache.flags < 0 ? 0 : 1;
b996ad0e RG	301	break;
b996ad0e RG	302	case POWER_SUPPLY_PROP_CURRENT_NOW:
297a533b	303	ret = bq27x00_battery_current(di, val);
b996ad0e RG	304	break;
b996ad0e RG	305	case POWER_SUPPLY_PROP_CAPACITY:
297a533b	306	ret = bq27x00_simple_value(di->cache.capacity, val);
b996ad0e RG	307	break;
b996ad0e RG	308	case POWER_SUPPLY_PROP_TEMP:
297a533b	309	ret = bq27x00_battery_temperature(di, val);
b996ad0e	310	break;
4e924a81	311	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
297a533b	312	ret = bq27x00_simple_value(di->cache.time_to_empty, val);
4e924a81 GI	313	break;
4e924a81 GI	314	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
297a533b	315	ret = bq27x00_simple_value(di->cache.time_to_empty_avg, val);
4e924a81 GI	316	break;
4e924a81 GI	317	case POWER_SUPPLY_PROP_TIME_TO_FULL_NOW:
297a533b	318	ret = bq27x00_simple_value(di->cache.time_to_full, val);
4e924a81	319	break;
5661f334 LPC	320	case POWER_SUPPLY_PROP_TECHNOLOGY:
	321	val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
	322	break;
b996ad0e RG	323	default:
	324	return -EINVAL;
	325	}
	326
4e924a81	327	return ret;
b996ad0e RG	328	}
b996ad0e RG	329
a40402ef	330	static int bq27x00_powersupply_init(struct bq27x00_device_info *di)
b996ad0e	331	{
a40402ef LPC	332	int ret;
a40402ef LPC	333
b996ad0e RG	334	di->bat.type = POWER_SUPPLY_TYPE_BATTERY;
	335	di->bat.properties = bq27x00_battery_props;
	336	di->bat.num_properties = ARRAY_SIZE(bq27x00_battery_props);
	337	di->bat.get_property = bq27x00_battery_get_property;
	338	di->bat.external_power_changed = NULL;
a40402ef LPC	339
	340	ret = power_supply_register(di->dev, &di->bat);
	341	if (ret) {
	342	dev_err(di->dev, "failed to register battery: %d\n", ret);
	343	return ret;
	344	}
	345
	346	dev_info(di->dev, "support ver. %s enabled\n", DRIVER_VERSION);
	347
297a533b LPC	348	bq27x00_update(di);
297a533b LPC	349
a40402ef	350	return 0;
b996ad0e RG	351	}
b996ad0e RG	352
7fb7ba58 LPC	353
	354	/* i2c specific code */
	355	#ifdef CONFIG_BATTERY_BQ27X00_I2C
	356
	357	/* If the system has several batteries we need a different name for each
	358	* of them...
b996ad0e	359	*/
7fb7ba58 LPC	360	static DEFINE_IDR(battery_id);
7fb7ba58 LPC	361	static DEFINE_MUTEX(battery_mutex);
b996ad0e	362
297a533b	363	static int bq27x00_read_i2c(struct bq27x00_device_info *di, u8 reg, bool single)
b996ad0e	364	{
a40402ef	365	struct i2c_client *client = to_i2c_client(di->dev);
b996ad0e RG	366	struct i2c_msg msg[1];
b996ad0e RG	367	unsigned char data[2];
297a533b	368	int ret;
b996ad0e RG	369
	370	if (!client->adapter)
	371	return -ENODEV;
	372
	373	msg->addr = client->addr;
	374	msg->flags = 0;
	375	msg->len = 1;
	376	msg->buf = data;
	377
	378	data[0] = reg;
297a533b	379	ret = i2c_transfer(client->adapter, msg, 1);
b996ad0e	380
297a533b	381	if (ret >= 0) {
a40402ef	382	if (!single)
b996ad0e RG	383	msg->len = 2;
	384	else
	385	msg->len = 1;
	386
	387	msg->flags = I2C_M_RD;
297a533b LPC	388	ret = i2c_transfer(client->adapter, msg, 1);
297a533b LPC	389	if (ret >= 0) {
a40402ef	390	if (!single)
297a533b	391	ret = get_unaligned_le16(data);
b996ad0e	392	else
297a533b	393	ret = data[0];
b996ad0e RG	394	}
b996ad0e RG	395	}
297a533b	396	return ret;
b996ad0e RG	397	}
b996ad0e RG	398
e20908d9	399	static int bq27x00_battery_probe(struct i2c_client *client,
b996ad0e RG	400	const struct i2c_device_id *id)
	401	{
	402	char *name;
	403	struct bq27x00_device_info *di;
b996ad0e RG	404	int num;
	405	int retval = 0;
	406
	407	/* Get new ID for the new battery device */
	408	retval = idr_pre_get(&battery_id, GFP_KERNEL);
	409	if (retval == 0)
	410	return -ENOMEM;
	411	mutex_lock(&battery_mutex);
	412	retval = idr_get_new(&battery_id, client, &num);
	413	mutex_unlock(&battery_mutex);
	414	if (retval < 0)
	415	return retval;
	416
e20908d9	417	name = kasprintf(GFP_KERNEL, "%s-%d", id->name, num);
b996ad0e RG	418	if (!name) {
	419	dev_err(&client->dev, "failed to allocate device name\n");
	420	retval = -ENOMEM;
	421	goto batt_failed_1;
	422	}
	423
	424	di = kzalloc(sizeof(*di), GFP_KERNEL);
	425	if (!di) {
	426	dev_err(&client->dev, "failed to allocate device info data\n");
	427	retval = -ENOMEM;
	428	goto batt_failed_2;
	429	}
a40402ef	430
b996ad0e	431	di->id = num;
a40402ef	432	di->dev = &client->dev;
e20908d9	433	di->chip = id->driver_data;
a40402ef LPC	434	di->bat.name = name;
a40402ef LPC	435	di->bus.read = &bq27x00_read_i2c;
b996ad0e	436
a40402ef	437	if (bq27x00_powersupply_init(di))
b996ad0e	438	goto batt_failed_3;
b996ad0e RG	439
b996ad0e RG	440	i2c_set_clientdata(client, di);
b996ad0e RG	441
	442	return 0;
	443
b996ad0e RG	444	batt_failed_3:
	445	kfree(di);
	446	batt_failed_2:
	447	kfree(name);
	448	batt_failed_1:
	449	mutex_lock(&battery_mutex);
	450	idr_remove(&battery_id, num);
	451	mutex_unlock(&battery_mutex);
	452
	453	return retval;
	454	}
	455
e20908d9	456	static int bq27x00_battery_remove(struct i2c_client *client)
b996ad0e RG	457	{
	458	struct bq27x00_device_info *di = i2c_get_clientdata(client);
	459
	460	power_supply_unregister(&di->bat);
	461
	462	kfree(di->bat.name);
	463
	464	mutex_lock(&battery_mutex);
	465	idr_remove(&battery_id, di->id);
	466	mutex_unlock(&battery_mutex);
	467
	468	kfree(di);
	469
	470	return 0;
	471	}
	472
e20908d9 GI	473	static const struct i2c_device_id bq27x00_id[] = {
	474	{ "bq27200", BQ27000 }, /* bq27200 is same as bq27000, but with i2c */
	475	{ "bq27500", BQ27500 },
b996ad0e RG	476	{},
	477	};
	478
e20908d9	479	static struct i2c_driver bq27x00_battery_driver = {
b996ad0e	480	.driver = {
e20908d9	481	.name = "bq27x00-battery",
b996ad0e	482	},
e20908d9 GI	483	.probe = bq27x00_battery_probe,
	484	.remove = bq27x00_battery_remove,
	485	.id_table = bq27x00_id,
b996ad0e RG	486	};
b996ad0e RG	487
7fb7ba58 LPC	488	static inline int bq27x00_battery_i2c_init(void)
	489	{
	490	int ret = i2c_add_driver(&bq27x00_battery_driver);
	491	if (ret)
	492	printk(KERN_ERR "Unable to register BQ27x00 i2c driver\n");
	493
	494	return ret;
	495	}
	496
	497	static inline void bq27x00_battery_i2c_exit(void)
	498	{
	499	i2c_del_driver(&bq27x00_battery_driver);
	500	}
	501
	502	#else
	503
	504	static inline int bq27x00_battery_i2c_init(void) { return 0; }
	505	static inline void bq27x00_battery_i2c_exit(void) {};
	506
	507	#endif
	508
	509	/* platform specific code */
	510	#ifdef CONFIG_BATTERY_BQ27X00_PLATFORM
	511
	512	static int bq27000_read_platform(struct bq27x00_device_info *di, u8 reg,
297a533b	513	bool single)
7fb7ba58 LPC	514	{
	515	struct device *dev = di->dev;
	516	struct bq27000_platform_data *pdata = dev->platform_data;
	517	unsigned int timeout = 3;
	518	int upper, lower;
	519	int temp;
	520
	521	if (!single) {
	522	/* Make sure the value has not changed in between reading the
	523	* lower and the upper part */
	524	upper = pdata->read(dev, reg + 1);
	525	do {
	526	temp = upper;
	527	if (upper < 0)
	528	return upper;
	529
	530	lower = pdata->read(dev, reg);
	531	if (lower < 0)
	532	return lower;
	533
	534	upper = pdata->read(dev, reg + 1);
	535	} while (temp != upper && --timeout);
	536
	537	if (timeout == 0)
	538	return -EIO;
	539
297a533b	540	return (upper << 8) \| lower;
7fb7ba58	541	}
297a533b LPC	542
297a533b LPC	543	return pdata->read(dev, reg);
7fb7ba58 LPC	544	}
	545
	546	static int __devinit bq27000_battery_probe(struct platform_device *pdev)
	547	{
	548	struct bq27x00_device_info *di;
	549	struct bq27000_platform_data *pdata = pdev->dev.platform_data;
	550	int ret;
	551
	552	if (!pdata) {
	553	dev_err(&pdev->dev, "no platform_data supplied\n");
	554	return -EINVAL;
	555	}
	556
	557	if (!pdata->read) {
	558	dev_err(&pdev->dev, "no hdq read callback supplied\n");
	559	return -EINVAL;
	560	}
	561
	562	di = kzalloc(sizeof(*di), GFP_KERNEL);
	563	if (!di) {
	564	dev_err(&pdev->dev, "failed to allocate device info data\n");
	565	return -ENOMEM;
	566	}
	567
	568	platform_set_drvdata(pdev, di);
	569
	570	di->dev = &pdev->dev;
	571	di->chip = BQ27000;
	572
	573	di->bat.name = pdata->name ?: dev_name(&pdev->dev);
	574	di->bus.read = &bq27000_read_platform;
	575
	576	ret = bq27x00_powersupply_init(di);
	577	if (ret)
	578	goto err_free;
	579
	580	return 0;
	581
	582	err_free:
	583	platform_set_drvdata(pdev, NULL);
	584	kfree(di);
	585
	586	return ret;
	587	}
	588
	589	static int __devexit bq27000_battery_remove(struct platform_device *pdev)
	590	{
	591	struct bq27x00_device_info *di = platform_get_drvdata(pdev);
	592
	593	power_supply_unregister(&di->bat);
	594	platform_set_drvdata(pdev, NULL);
	595	kfree(di);
	596
	597	return 0;
	598	}
	599
	600	static struct platform_driver bq27000_battery_driver = {
	601	.probe = bq27000_battery_probe,
	602	.remove = __devexit_p(bq27000_battery_remove),
	603	.driver = {
	604	.name = "bq27000-battery",
	605	.owner = THIS_MODULE,
	606	},
	607	};
608
609	static inline int bq27x00_battery_platform_init(void)
610	{
611	int ret = platform_driver_register(&bq27000_battery_driver);
612	if (ret)
613	printk(KERN_ERR "Unable to register BQ27000 platform driver\n");
614
615	return ret;
616	}
617
618	static inline void bq27x00_battery_platform_exit(void)
619	{
620	platform_driver_unregister(&bq27000_battery_driver);
621	}
622
623	#else
624
625	static inline int bq27x00_battery_platform_init(void) { return 0; }
626	static inline void bq27x00_battery_platform_exit(void) {};
627
628	#endif
629
630	/*
631	* Module stuff
632	*/
633
b996ad0e RG	634	static int __init bq27x00_battery_init(void)
	635	{
	636	int ret;
	637
7fb7ba58 LPC	638	ret = bq27x00_battery_i2c_init();
	639	if (ret)
	640	return ret;
	641
	642	ret = bq27x00_battery_platform_init();
b996ad0e	643	if (ret)
7fb7ba58	644	bq27x00_battery_i2c_exit();
b996ad0e RG	645
	646	return ret;
	647	}
	648	module_init(bq27x00_battery_init);
	649
	650	static void __exit bq27x00_battery_exit(void)
	651	{
7fb7ba58 LPC	652	bq27x00_battery_platform_exit();
7fb7ba58 LPC	653	bq27x00_battery_i2c_exit();
b996ad0e RG	654	}
	655	module_exit(bq27x00_battery_exit);
	656
	657	MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
	658	MODULE_DESCRIPTION("BQ27x00 battery monitor driver");
	659	MODULE_LICENSE("GPL");