[linux-2.6-block.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>
 *
 * 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 <asm/unaligned.h>

#define DRIVER_VERSION			"1.0.0"

#define BQ27x00_REG_TEMP		0x06
#define BQ27x00_REG_VOLT		0x08
#define BQ27x00_REG_RSOC		0x0B /* Relative State-of-Charge */
#define BQ27x00_REG_AI			0x14
#define BQ27x00_REG_FLAGS		0x0A

/* 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);

struct bq27x00_device_info;
struct bq27x00_access_methods {
	int (*read)(u8 reg, int *rt_value, int b_single,
		struct bq27x00_device_info *di);
};

struct bq27x00_device_info {
	struct device 		*dev;
	int			id;
	struct bq27x00_access_methods	*bus;
	struct power_supply	bat;

	struct i2c_client	*client;
};

static enum power_supply_property bq27x00_battery_props[] = {
	POWER_SUPPLY_PROP_PRESENT,
	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	POWER_SUPPLY_PROP_CURRENT_NOW,
	POWER_SUPPLY_PROP_CAPACITY,
	POWER_SUPPLY_PROP_TEMP,
};

/*
 * Common code for BQ27x00 devices
 */

static int bq27x00_read(u8 reg, int *rt_value, int b_single,
			struct bq27x00_device_info *di)
{
	return di->bus->read(reg, rt_value, b_single, di);
}

/*
 * Return the battery temperature in tenths of degree Celsius
 * Or < 0 if something fails.
 */
static int bq27x00_battery_temperature(struct bq27x00_device_info *di)
{
	int ret;
	int temp = 0;

	ret = bq27x00_read(BQ27x00_REG_TEMP, &temp, 0, di);
	if (ret) {
		dev_err(di->dev, "error reading temperature\n");
		return ret;
	}

	return ((temp >> 2) - 273) * 10;
}

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

	ret = bq27x00_read(BQ27x00_REG_VOLT, &volt, 0, di);
	if (ret) {
		dev_err(di->dev, "error reading voltage\n");
		return ret;
	}

	return volt;
}

/*
 * 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)
{
	int ret;
	int curr = 0;
	int flags = 0;

	ret = bq27x00_read(BQ27x00_REG_AI, &curr, 0, di);
	if (ret) {
		dev_err(di->dev, "error reading current\n");
		return 0;
	}
	ret = bq27x00_read(BQ27x00_REG_FLAGS, &flags, 0, di);
	if (ret < 0) {
		dev_err(di->dev, "error reading flags\n");
		return 0;
	}
	if ((flags & (1 << 7)) != 0) {
		dev_dbg(di->dev, "negative current!\n");
		return -curr;
	}
	return curr;
}

/*
 * Return the battery Relative State-of-Charge
 * Or < 0 if something fails.
 */
static int bq27x00_battery_rsoc(struct bq27x00_device_info *di)
{
	int ret;
	int rsoc = 0;

	ret = bq27x00_read(BQ27x00_REG_RSOC, &rsoc, 1, di);
	if (ret) {
		dev_err(di->dev, "error reading relative State-of-Charge\n");
		return ret;
	}

	return rsoc;
}

#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)
{
	struct bq27x00_device_info *di = to_bq27x00_device_info(psy);

	switch (psp) {
	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
	case POWER_SUPPLY_PROP_PRESENT:
		val->intval = bq27x00_battery_voltage(di);
		if (psp == POWER_SUPPLY_PROP_PRESENT)
			val->intval = val->intval <= 0 ? 0 : 1;
		break;
	case POWER_SUPPLY_PROP_CURRENT_NOW:
		val->intval = bq27x00_battery_current(di);
		break;
	case POWER_SUPPLY_PROP_CAPACITY:
		val->intval = bq27x00_battery_rsoc(di);
		break;
	case POWER_SUPPLY_PROP_TEMP:
		val->intval = bq27x00_battery_temperature(di);
		break;
	default:
		return -EINVAL;
	}

	return 0;
}

static void bq27x00_powersupply_init(struct bq27x00_device_info *di)
{
	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;
}

/*
 * BQ27200 specific code
 */

static int bq27200_read(u8 reg, int *rt_value, int b_single,
			struct bq27x00_device_info *di)
{
	struct i2c_client *client = di->client;
	struct i2c_msg msg[1];
	unsigned char data[2];
	int err;

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

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

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

	if (err >= 0) {
		if (!b_single)
			msg->len = 2;
		else
			msg->len = 1;

		msg->flags = I2C_M_RD;
		err = i2c_transfer(client->adapter, msg, 1);
		if (err >= 0) {
			if (!b_single)
				*rt_value = get_unaligned_le16(data);
			else
				*rt_value = data[0];

			return 0;
		}
	}
	return err;
}

static int bq27200_battery_probe(struct i2c_client *client,
				 const struct i2c_device_id *id)
{
	char *name;
	struct bq27x00_device_info *di;
	struct bq27x00_access_methods *bus;
	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, "bq27200-%d", 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;

	bus = kzalloc(sizeof(*bus), GFP_KERNEL);
	if (!bus) {
		dev_err(&client->dev, "failed to allocate access method "
					"data\n");
		retval = -ENOMEM;
		goto batt_failed_3;
	}

	i2c_set_clientdata(client, di);
	di->dev = &client->dev;
	di->bat.name = name;
	bus->read = &bq27200_read;
	di->bus = bus;
	di->client = client;

	bq27x00_powersupply_init(di);

	retval = power_supply_register(&client->dev, &di->bat);
	if (retval) {
		dev_err(&client->dev, "failed to register battery\n");
		goto batt_failed_4;
	}

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

	return 0;

batt_failed_4:
	kfree(bus);
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 bq27200_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;
}

/*
 * Module stuff
 */

static const struct i2c_device_id bq27200_id[] = {
	{ "bq27200", 0 },
	{},
};

static struct i2c_driver bq27200_battery_driver = {
	.driver = {
		.name = "bq27200-battery",
	},
	.probe = bq27200_battery_probe,
	.remove = bq27200_battery_remove,
	.id_table = bq27200_id,
};

static int __init bq27x00_battery_init(void)
{
	int ret;

	ret = i2c_add_driver(&bq27200_battery_driver);
	if (ret)
		printk(KERN_ERR "Unable to register BQ27200 driver\n");

	return ret;
}
module_init(bq27x00_battery_init);

static void __exit bq27x00_battery_exit(void)
{
	i2c_del_driver(&bq27200_battery_driver);
}
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>
	6	*
	7	* Based on a previous work by Copyright (C) 2008 Texas Instruments, Inc.
	8	*
	9	* This package is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License version 2 as
	11	* published by the Free Software Foundation.
	12	*
	13	* THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
	14	* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
	15	* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
	16	*
	17	*/
	18	#include <linux/module.h>
	19	#include <linux/param.h>
	20	#include <linux/jiffies.h>
	21	#include <linux/workqueue.h>
	22	#include <linux/delay.h>
	23	#include <linux/platform_device.h>
	24	#include <linux/power_supply.h>
	25	#include <linux/idr.h>
b996ad0e	26	#include <linux/i2c.h>
8aef7e8f	27	#include <asm/unaligned.h>
b996ad0e RG	28
	29	#define DRIVER_VERSION "1.0.0"
	30
	31	#define BQ27x00_REG_TEMP 0x06
	32	#define BQ27x00_REG_VOLT 0x08
	33	#define BQ27x00_REG_RSOC 0x0B /* Relative State-of-Charge */
	34	#define BQ27x00_REG_AI 0x14
	35	#define BQ27x00_REG_FLAGS 0x0A
b996ad0e RG	36
	37	/* If the system has several batteries we need a different name for each
	38	* of them...
	39	*/
	40	static DEFINE_IDR(battery_id);
	41	static DEFINE_MUTEX(battery_mutex);
	42
	43	struct bq27x00_device_info;
	44	struct bq27x00_access_methods {
	45	int (read)(u8 reg, int rt_value, int b_single,
	46	struct bq27x00_device_info *di);
	47	};
	48
	49	struct bq27x00_device_info {
	50	struct device *dev;
	51	int id;
b996ad0e RG	52	struct bq27x00_access_methods *bus;
	53	struct power_supply bat;
	54
	55	struct i2c_client *client;
	56	};
	57
	58	static enum power_supply_property bq27x00_battery_props[] = {
	59	POWER_SUPPLY_PROP_PRESENT,
	60	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	61	POWER_SUPPLY_PROP_CURRENT_NOW,
	62	POWER_SUPPLY_PROP_CAPACITY,
	63	POWER_SUPPLY_PROP_TEMP,
	64	};
	65
	66	/*
	67	* Common code for BQ27x00 devices
	68	*/
	69
	70	static int bq27x00_read(u8 reg, int *rt_value, int b_single,
	71	struct bq27x00_device_info *di)
	72	{
97f70c23	73	return di->bus->read(reg, rt_value, b_single, di);
b996ad0e RG	74	}
	75
	76	/*
b4de3608	77	* Return the battery temperature in tenths of degree Celsius
b996ad0e RG	78	* Or < 0 if something fails.
	79	*/
	80	static int bq27x00_battery_temperature(struct bq27x00_device_info *di)
	81	{
	82	int ret;
	83	int temp = 0;
	84
	85	ret = bq27x00_read(BQ27x00_REG_TEMP, &temp, 0, di);
	86	if (ret) {
	87	dev_err(di->dev, "error reading temperature\n");
	88	return ret;
	89	}
	90
b4de3608	91	return ((temp >> 2) - 273) * 10;
b996ad0e RG	92	}
	93
	94	/*
	95	* Return the battery Voltage in milivolts
	96	* Or < 0 if something fails.
	97	*/
	98	static int bq27x00_battery_voltage(struct bq27x00_device_info *di)
	99	{
	100	int ret;
	101	int volt = 0;
	102
	103	ret = bq27x00_read(BQ27x00_REG_VOLT, &volt, 0, di);
	104	if (ret) {
	105	dev_err(di->dev, "error reading voltage\n");
	106	return ret;
	107	}
	108
	109	return volt;
	110	}
	111
	112	/*
	113	* Return the battery average current
	114	* Note that current can be negative signed as well
	115	* Or 0 if something fails.
	116	*/
	117	static int bq27x00_battery_current(struct bq27x00_device_info *di)
	118	{
	119	int ret;
	120	int curr = 0;
	121	int flags = 0;
	122
	123	ret = bq27x00_read(BQ27x00_REG_AI, &curr, 0, di);
	124	if (ret) {
	125	dev_err(di->dev, "error reading current\n");
	126	return 0;
	127	}
	128	ret = bq27x00_read(BQ27x00_REG_FLAGS, &flags, 0, di);
	129	if (ret < 0) {
	130	dev_err(di->dev, "error reading flags\n");
	131	return 0;
	132	}
	133	if ((flags & (1 << 7)) != 0) {
	134	dev_dbg(di->dev, "negative current!\n");
	135	return -curr;
	136	}
	137	return curr;
	138	}
	139
	140	/*
	141	* Return the battery Relative State-of-Charge
	142	* Or < 0 if something fails.
	143	*/
	144	static int bq27x00_battery_rsoc(struct bq27x00_device_info *di)
	145	{
	146	int ret;
	147	int rsoc = 0;
	148
	149	ret = bq27x00_read(BQ27x00_REG_RSOC, &rsoc, 1, di);
	150	if (ret) {
	151	dev_err(di->dev, "error reading relative State-of-Charge\n");
	152	return ret;
	153	}
	154
97f70c23	155	return rsoc;
b996ad0e RG	156	}
	157
	158	#define to_bq27x00_device_info(x) container_of((x), \
	159	struct bq27x00_device_info, bat);
	160
	161	static int bq27x00_battery_get_property(struct power_supply *psy,
	162	enum power_supply_property psp,
	163	union power_supply_propval *val)
	164	{
	165	struct bq27x00_device_info *di = to_bq27x00_device_info(psy);
	166
	167	switch (psp) {
	168	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
	169	case POWER_SUPPLY_PROP_PRESENT:
	170	val->intval = bq27x00_battery_voltage(di);
	171	if (psp == POWER_SUPPLY_PROP_PRESENT)
	172	val->intval = val->intval <= 0 ? 0 : 1;
	173	break;
	174	case POWER_SUPPLY_PROP_CURRENT_NOW:
	175	val->intval = bq27x00_battery_current(di);
	176	break;
	177	case POWER_SUPPLY_PROP_CAPACITY:
	178	val->intval = bq27x00_battery_rsoc(di);
	179	break;
	180	case POWER_SUPPLY_PROP_TEMP:
	181	val->intval = bq27x00_battery_temperature(di);
	182	break;
	183	default:
	184	return -EINVAL;
	185	}
	186
	187	return 0;
	188	}
	189
	190	static void bq27x00_powersupply_init(struct bq27x00_device_info *di)
	191	{
	192	di->bat.type = POWER_SUPPLY_TYPE_BATTERY;
	193	di->bat.properties = bq27x00_battery_props;
	194	di->bat.num_properties = ARRAY_SIZE(bq27x00_battery_props);
	195	di->bat.get_property = bq27x00_battery_get_property;
	196	di->bat.external_power_changed = NULL;
	197	}
	198
	199	/*
	200	* BQ27200 specific code
	201	*/
	202
	203	static int bq27200_read(u8 reg, int *rt_value, int b_single,
	204	struct bq27x00_device_info *di)
	205	{
	206	struct i2c_client *client = di->client;
	207	struct i2c_msg msg[1];
	208	unsigned char data[2];
	209	int err;
	210
	211	if (!client->adapter)
	212	return -ENODEV;
	213
	214	msg->addr = client->addr;
	215	msg->flags = 0;
	216	msg->len = 1;
	217	msg->buf = data;
	218
	219	data[0] = reg;
220	err = i2c_transfer(client->adapter, msg, 1);
221
222	if (err >= 0) {
223	if (!b_single)
224	msg->len = 2;
225	else
226	msg->len = 1;
227
228	msg->flags = I2C_M_RD;
229	err = i2c_transfer(client->adapter, msg, 1);
230	if (err >= 0) {
231	if (!b_single)
97f70c23	232	*rt_value = get_unaligned_le16(data);
b996ad0e RG	233	else
	234	*rt_value = data[0];
	235
	236	return 0;
	237	}
	238	}
	239	return err;
	240	}
	241
	242	static int bq27200_battery_probe(struct i2c_client *client,
	243	const struct i2c_device_id *id)
	244	{
	245	char *name;
	246	struct bq27x00_device_info *di;
	247	struct bq27x00_access_methods *bus;
	248	int num;
	249	int retval = 0;
	250
	251	/* Get new ID for the new battery device */
	252	retval = idr_pre_get(&battery_id, GFP_KERNEL);
	253	if (retval == 0)
	254	return -ENOMEM;
	255	mutex_lock(&battery_mutex);
	256	retval = idr_get_new(&battery_id, client, &num);
	257	mutex_unlock(&battery_mutex);
	258	if (retval < 0)
	259	return retval;
	260
	261	name = kasprintf(GFP_KERNEL, "bq27200-%d", num);
	262	if (!name) {
	263	dev_err(&client->dev, "failed to allocate device name\n");
	264	retval = -ENOMEM;
	265	goto batt_failed_1;
	266	}
	267
	268	di = kzalloc(sizeof(*di), GFP_KERNEL);
	269	if (!di) {
	270	dev_err(&client->dev, "failed to allocate device info data\n");
	271	retval = -ENOMEM;
	272	goto batt_failed_2;
	273	}
	274	di->id = num;
	275
	276	bus = kzalloc(sizeof(*bus), GFP_KERNEL);
	277	if (!bus) {
	278	dev_err(&client->dev, "failed to allocate access method "
	279	"data\n");
	280	retval = -ENOMEM;
	281	goto batt_failed_3;
	282	}
	283
	284	i2c_set_clientdata(client, di);
	285	di->dev = &client->dev;
	286	di->bat.name = name;
	287	bus->read = &bq27200_read;
	288	di->bus = bus;
	289	di->client = client;
	290
	291	bq27x00_powersupply_init(di);
	292
	293	retval = power_supply_register(&client->dev, &di->bat);
	294	if (retval) {
	295	dev_err(&client->dev, "failed to register battery\n");
	296	goto batt_failed_4;
297	}
298
299	dev_info(&client->dev, "support ver. %s enabled\n", DRIVER_VERSION);
300
301	return 0;
302
303	batt_failed_4:
304	kfree(bus);
305	batt_failed_3:
306	kfree(di);
307	batt_failed_2:
308	kfree(name);
309	batt_failed_1:
310	mutex_lock(&battery_mutex);
311	idr_remove(&battery_id, num);
312	mutex_unlock(&battery_mutex);
313
314	return retval;
315	}
316
317	static int bq27200_battery_remove(struct i2c_client *client)
318	{
319	struct bq27x00_device_info *di = i2c_get_clientdata(client);
320
321	power_supply_unregister(&di->bat);
322
323	kfree(di->bat.name);
324
325	mutex_lock(&battery_mutex);
326	idr_remove(&battery_id, di->id);
327	mutex_unlock(&battery_mutex);
328
329	kfree(di);
330
331	return 0;
332	}
333
334	/*
335	* Module stuff
336	*/
337
338	static const struct i2c_device_id bq27200_id[] = {
339	{ "bq27200", 0 },
340	{},
341	};
342
343	static struct i2c_driver bq27200_battery_driver = {
344	.driver = {
345	.name = "bq27200-battery",
346	},
347	.probe = bq27200_battery_probe,
348	.remove = bq27200_battery_remove,
349	.id_table = bq27200_id,
350	};
351
352	static int __init bq27x00_battery_init(void)
353	{
354	int ret;
355
356	ret = i2c_add_driver(&bq27200_battery_driver);
357	if (ret)
358	printk(KERN_ERR "Unable to register BQ27200 driver\n");
359
360	return ret;
361	}
362	module_init(bq27x00_battery_init);
363
364	static void __exit bq27x00_battery_exit(void)
365	{
366	i2c_del_driver(&bq27200_battery_driver);
367	}
368	module_exit(bq27x00_battery_exit);
369
370	MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
371	MODULE_DESCRIPTION("BQ27x00 battery monitor driver");
372	MODULE_LICENSE("GPL");