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

/*
 * BQ27x00 battery driver
 *
 * Copyright (C) 2008 Rodolfo Giometti <[email protected]>
 * Copyright (C) 2008 Eurotech S.p.A. <[email protected]>
 *
 * 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;
	int			voltage_uV;
	int			current_uA;
	int			temp_C;
	int			charge_rsoc;
	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)
{
	int ret;

	ret = di->bus->read(reg, rt_value, b_single, di);
	*rt_value = be16_to_cpu(*rt_value);

	return ret;
}

/*
 * Return the battery temperature in Celsius degrees
 * 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;
}

/*
 * 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 >> 8;
}

#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_be16(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 <[email protected]>");
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 <[email protected]>
	5	* Copyright (C) 2008 Eurotech S.p.A. <[email protected]>
	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;
	52	int voltage_uV;
	53	int current_uA;
	54	int temp_C;
	55	int charge_rsoc;
	56	struct bq27x00_access_methods *bus;
	57	struct power_supply bat;
	58
	59	struct i2c_client *client;
	60	};
	61
	62	static enum power_supply_property bq27x00_battery_props[] = {
	63	POWER_SUPPLY_PROP_PRESENT,
	64	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	65	POWER_SUPPLY_PROP_CURRENT_NOW,
	66	POWER_SUPPLY_PROP_CAPACITY,
	67	POWER_SUPPLY_PROP_TEMP,
	68	};
	69
	70	/*
	71	* Common code for BQ27x00 devices
	72	*/
	73
	74	static int bq27x00_read(u8 reg, int *rt_value, int b_single,
	75	struct bq27x00_device_info *di)
	76	{
	77	int ret;
	78
	79	ret = di->bus->read(reg, rt_value, b_single, di);
	80	rt_value = be16_to_cpu(rt_value);
	81
	82	return ret;
	83	}
	84
	85	/*
b731d7b6	86	* Return the battery temperature in Celsius degrees
b996ad0e RG	87	* Or < 0 if something fails.
	88	*/
	89	static int bq27x00_battery_temperature(struct bq27x00_device_info *di)
	90	{
	91	int ret;
	92	int temp = 0;
	93
	94	ret = bq27x00_read(BQ27x00_REG_TEMP, &temp, 0, di);
	95	if (ret) {
	96	dev_err(di->dev, "error reading temperature\n");
	97	return ret;
	98	}
	99
	100	return (temp >> 2) - 273;
	101	}
	102
	103	/*
	104	* Return the battery Voltage in milivolts
	105	* Or < 0 if something fails.
	106	*/
	107	static int bq27x00_battery_voltage(struct bq27x00_device_info *di)
	108	{
	109	int ret;
	110	int volt = 0;
	111
	112	ret = bq27x00_read(BQ27x00_REG_VOLT, &volt, 0, di);
	113	if (ret) {
	114	dev_err(di->dev, "error reading voltage\n");
	115	return ret;
	116	}
	117
	118	return volt;
	119	}
	120
	121	/*
	122	* Return the battery average current
	123	* Note that current can be negative signed as well
	124	* Or 0 if something fails.
	125	*/
	126	static int bq27x00_battery_current(struct bq27x00_device_info *di)
	127	{
	128	int ret;
	129	int curr = 0;
	130	int flags = 0;
	131
	132	ret = bq27x00_read(BQ27x00_REG_AI, &curr, 0, di);
	133	if (ret) {
	134	dev_err(di->dev, "error reading current\n");
	135	return 0;
	136	}
	137	ret = bq27x00_read(BQ27x00_REG_FLAGS, &flags, 0, di);
	138	if (ret < 0) {
	139	dev_err(di->dev, "error reading flags\n");
	140	return 0;
	141	}
	142	if ((flags & (1 << 7)) != 0) {
	143	dev_dbg(di->dev, "negative current!\n");
	144	return -curr;
	145	}
	146	return curr;
	147	}
	148
	149	/*
	150	* Return the battery Relative State-of-Charge
151	* Or < 0 if something fails.
152	*/
153	static int bq27x00_battery_rsoc(struct bq27x00_device_info *di)
154	{
155	int ret;
156	int rsoc = 0;
157
158	ret = bq27x00_read(BQ27x00_REG_RSOC, &rsoc, 1, di);
159	if (ret) {
160	dev_err(di->dev, "error reading relative State-of-Charge\n");
161	return ret;
162	}
163
164	return rsoc >> 8;
165	}
166
167	#define to_bq27x00_device_info(x) container_of((x), \
168	struct bq27x00_device_info, bat);
169
170	static int bq27x00_battery_get_property(struct power_supply *psy,
171	enum power_supply_property psp,
172	union power_supply_propval *val)
173	{
174	struct bq27x00_device_info *di = to_bq27x00_device_info(psy);
175
176	switch (psp) {
177	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
178	case POWER_SUPPLY_PROP_PRESENT:
179	val->intval = bq27x00_battery_voltage(di);
180	if (psp == POWER_SUPPLY_PROP_PRESENT)
181	val->intval = val->intval <= 0 ? 0 : 1;
182	break;
183	case POWER_SUPPLY_PROP_CURRENT_NOW:
184	val->intval = bq27x00_battery_current(di);
185	break;
186	case POWER_SUPPLY_PROP_CAPACITY:
187	val->intval = bq27x00_battery_rsoc(di);
188	break;
189	case POWER_SUPPLY_PROP_TEMP:
190	val->intval = bq27x00_battery_temperature(di);
191	break;
192	default:
193	return -EINVAL;
194	}
195
196	return 0;
197	}
198
199	static void bq27x00_powersupply_init(struct bq27x00_device_info *di)
200	{
201	di->bat.type = POWER_SUPPLY_TYPE_BATTERY;
202	di->bat.properties = bq27x00_battery_props;
203	di->bat.num_properties = ARRAY_SIZE(bq27x00_battery_props);
204	di->bat.get_property = bq27x00_battery_get_property;
205	di->bat.external_power_changed = NULL;
206	}
207
208	/*
209	* BQ27200 specific code
210	*/
211
212	static int bq27200_read(u8 reg, int *rt_value, int b_single,
213	struct bq27x00_device_info *di)
214	{
215	struct i2c_client *client = di->client;
216	struct i2c_msg msg[1];
217	unsigned char data[2];
218	int err;
219
220	if (!client->adapter)
221	return -ENODEV;
222
223	msg->addr = client->addr;
224	msg->flags = 0;
225	msg->len = 1;
226	msg->buf = data;
227
228	data[0] = reg;
229	err = i2c_transfer(client->adapter, msg, 1);
230
231	if (err >= 0) {
232	if (!b_single)
233	msg->len = 2;
234	else
235	msg->len = 1;
236
237	msg->flags = I2C_M_RD;
238	err = i2c_transfer(client->adapter, msg, 1);
239	if (err >= 0) {
240	if (!b_single)
8aef7e8f	241	*rt_value = get_unaligned_be16(data);
b996ad0e RG	242	else
	243	*rt_value = data[0];
	244
	245	return 0;
	246	}
	247	}
	248	return err;
	249	}
	250
	251	static int bq27200_battery_probe(struct i2c_client *client,
	252	const struct i2c_device_id *id)
	253	{
	254	char *name;
	255	struct bq27x00_device_info *di;
	256	struct bq27x00_access_methods *bus;
	257	int num;
	258	int retval = 0;
	259
	260	/* Get new ID for the new battery device */
	261	retval = idr_pre_get(&battery_id, GFP_KERNEL);
	262	if (retval == 0)
	263	return -ENOMEM;
	264	mutex_lock(&battery_mutex);
	265	retval = idr_get_new(&battery_id, client, &num);
	266	mutex_unlock(&battery_mutex);
	267	if (retval < 0)
	268	return retval;
	269
	270	name = kasprintf(GFP_KERNEL, "bq27200-%d", num);
	271	if (!name) {
	272	dev_err(&client->dev, "failed to allocate device name\n");
	273	retval = -ENOMEM;
	274	goto batt_failed_1;
	275	}
	276
	277	di = kzalloc(sizeof(*di), GFP_KERNEL);
	278	if (!di) {
	279	dev_err(&client->dev, "failed to allocate device info data\n");
	280	retval = -ENOMEM;
	281	goto batt_failed_2;
	282	}
	283	di->id = num;
	284
	285	bus = kzalloc(sizeof(*bus), GFP_KERNEL);
	286	if (!bus) {
	287	dev_err(&client->dev, "failed to allocate access method "
	288	"data\n");
	289	retval = -ENOMEM;
	290	goto batt_failed_3;
	291	}
	292
	293	i2c_set_clientdata(client, di);
	294	di->dev = &client->dev;
	295	di->bat.name = name;
	296	bus->read = &bq27200_read;
	297	di->bus = bus;
	298	di->client = client;
	299
	300	bq27x00_powersupply_init(di);
	301
	302	retval = power_supply_register(&client->dev, &di->bat);
	303	if (retval) {
	304	dev_err(&client->dev, "failed to register battery\n");
	305	goto batt_failed_4;
306	}
307
308	dev_info(&client->dev, "support ver. %s enabled\n", DRIVER_VERSION);
309
310	return 0;
311
312	batt_failed_4:
313	kfree(bus);
314	batt_failed_3:
315	kfree(di);
316	batt_failed_2:
317	kfree(name);
318	batt_failed_1:
319	mutex_lock(&battery_mutex);
320	idr_remove(&battery_id, num);
321	mutex_unlock(&battery_mutex);
322
323	return retval;
324	}
325
326	static int bq27200_battery_remove(struct i2c_client *client)
327	{
328	struct bq27x00_device_info *di = i2c_get_clientdata(client);
329
330	power_supply_unregister(&di->bat);
331
332	kfree(di->bat.name);
333
334	mutex_lock(&battery_mutex);
335	idr_remove(&battery_id, di->id);
336	mutex_unlock(&battery_mutex);
337
338	kfree(di);
339
340	return 0;
341	}
342
343	/*
344	* Module stuff
345	*/
346
347	static const struct i2c_device_id bq27200_id[] = {
348	{ "bq27200", 0 },
349	{},
350	};
351
352	static struct i2c_driver bq27200_battery_driver = {
353	.driver = {
354	.name = "bq27200-battery",
355	},
356	.probe = bq27200_battery_probe,
357	.remove = bq27200_battery_remove,
358	.id_table = bq27200_id,
359	};
360
361	static int __init bq27x00_battery_init(void)
362	{
363	int ret;
364
365	ret = i2c_add_driver(&bq27200_battery_driver);
366	if (ret)
367	printk(KERN_ERR "Unable to register BQ27200 driver\n");
368
369	return ret;
370	}
371	module_init(bq27x00_battery_init);
372
373	static void __exit bq27x00_battery_exit(void)
374	{
375	i2c_del_driver(&bq27200_battery_driver);
376	}
377	module_exit(bq27x00_battery_exit);
378
379	MODULE_AUTHOR("Rodolfo Giometti <[email protected]>");
380	MODULE_DESCRIPTION("BQ27x00 battery monitor driver");
381	MODULE_LICENSE("GPL");