[linux-2.6-block.git] / drivers / power / rx51_battery.c

/*
 * Nokia RX-51 battery driver
 *
 * Copyright (C) 2012  Pali Rohár <pali.rohar@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include <linux/module.h>
#include <linux/param.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/slab.h>
#include <linux/i2c/twl4030-madc.h>
#include <linux/iio/consumer.h>
#include <linux/of.h>

struct rx51_device_info {
	struct device *dev;
	struct power_supply *bat;
	struct power_supply_desc bat_desc;
	struct iio_channel *channel_temp;
	struct iio_channel *channel_bsi;
	struct iio_channel *channel_vbat;
};

/*
 * Read ADCIN channel value, code copied from maemo kernel
 */
static int rx51_battery_read_adc(struct iio_channel *channel)
{
	int val, err;
	err = iio_read_channel_average_raw(channel, &val);
	if (err < 0)
		return err;
	return val;
}

/*
 * Read ADCIN channel 12 (voltage) and convert RAW value to micro voltage
 * This conversion formula was extracted from maemo program bsi-read
 */
static int rx51_battery_read_voltage(struct rx51_device_info *di)
{
	int voltage = rx51_battery_read_adc(di->channel_vbat);

	if (voltage < 0) {
		dev_err(di->dev, "Could not read ADC: %d\n", voltage);
		return voltage;
	}

	return 1000 * (10000 * voltage / 1705);
}

/*
 * Temperature look-up tables
 * TEMP = (1/(t1 + 1/298) - 273.15)
 * Where t1 = (1/B) * ln((RAW_ADC_U * 2.5)/(R * I * 255))
 * Formula is based on experimental data, RX-51 CAL data, maemo program bme
 * and formula from da9052 driver with values R = 100, B = 3380, I = 0.00671
 */

/*
 * Table1 (temperature for first 25 RAW values)
 * Usage: TEMP = rx51_temp_table1[RAW]
 *   RAW is between 1 and 24
 *   TEMP is between 201 C and 55 C
 */
static u8 rx51_temp_table1[] = {
	255, 201, 159, 138, 124, 114, 106,  99,  94,  89,  85,  82,  78,  75,
	 73,  70,  68,  66,  64,  62,  61,  59,  57,  56,  55
};

/*
 * Table2 (lowest RAW value for temperature)
 * Usage: RAW = rx51_temp_table2[TEMP-rx51_temp_table2_first]
 *   TEMP is between 53 C and -32 C
 *   RAW is between 25 and 993
 */
#define rx51_temp_table2_first 53
static u16 rx51_temp_table2[] = {
	 25,  26,  27,  28,  29,  30,  31,  32,  33,  34,  35,  36,  37,  39,
	 40,  41,  43,  44,  46,  48,  49,  51,  53,  55,  57,  59,  61,  64,
	 66,  69,  71,  74,  77,  80,  83,  86,  90,  94,  97, 101, 106, 110,
	115, 119, 125, 130, 136, 141, 148, 154, 161, 168, 176, 184, 202, 211,
	221, 231, 242, 254, 266, 279, 293, 308, 323, 340, 357, 375, 395, 415,
	437, 460, 485, 511, 539, 568, 600, 633, 669, 706, 747, 790, 836, 885,
	937, 993, 1024
};

/*
 * Read ADCIN channel 0 (battery temp) and convert value to tenths of Celsius
 * Use Temperature look-up tables for conversation
 */
static int rx51_battery_read_temperature(struct rx51_device_info *di)
{
	int min = 0;
	int max = ARRAY_SIZE(rx51_temp_table2) - 1;
	int raw = rx51_battery_read_adc(di->channel_temp);

	if (raw < 0)
		dev_err(di->dev, "Could not read ADC: %d\n", raw);

	/* Zero and negative values are undefined */
	if (raw <= 0)
		return INT_MAX;

	/* ADC channels are 10 bit, higher value are undefined */
	if (raw >= (1 << 10))
		return INT_MIN;

	/* First check for temperature in first direct table */
	if (raw < ARRAY_SIZE(rx51_temp_table1))
		return rx51_temp_table1[raw] * 10;

	/* Binary search RAW value in second inverse table */
	while (max - min > 1) {
		int mid = (max + min) / 2;
		if (rx51_temp_table2[mid] <= raw)
			min = mid;
		else if (rx51_temp_table2[mid] > raw)
			max = mid;
		if (rx51_temp_table2[mid] == raw)
			break;
	}

	return (rx51_temp_table2_first - min) * 10;
}

/*
 * Read ADCIN channel 4 (BSI) and convert RAW value to micro Ah
 * This conversion formula was extracted from maemo program bsi-read
 */
static int rx51_battery_read_capacity(struct rx51_device_info *di)
{
	int capacity = rx51_battery_read_adc(di->channel_bsi);

	if (capacity < 0) {
		dev_err(di->dev, "Could not read ADC: %d\n", capacity);
		return capacity;
	}

	return 1280 * (1200 * capacity)/(1024 - capacity);
}

/*
 * Return power_supply property
 */
static int rx51_battery_get_property(struct power_supply *psy,
					enum power_supply_property psp,
					union power_supply_propval *val)
{
	struct rx51_device_info *di = power_supply_get_drvdata(psy);

	switch (psp) {
	case POWER_SUPPLY_PROP_TECHNOLOGY:
		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
		break;
	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
		val->intval = 4200000;
		break;
	case POWER_SUPPLY_PROP_PRESENT:
		val->intval = rx51_battery_read_voltage(di) ? 1 : 0;
		break;
	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
		val->intval = rx51_battery_read_voltage(di);
		break;
	case POWER_SUPPLY_PROP_TEMP:
		val->intval = rx51_battery_read_temperature(di);
		break;
	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
		val->intval = rx51_battery_read_capacity(di);
		break;
	default:
		return -EINVAL;
	}

	if (val->intval == INT_MAX || val->intval == INT_MIN)
		return -EINVAL;

	return 0;
}

static enum power_supply_property rx51_battery_props[] = {
	POWER_SUPPLY_PROP_TECHNOLOGY,
	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
	POWER_SUPPLY_PROP_PRESENT,
	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	POWER_SUPPLY_PROP_TEMP,
	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
};

static int rx51_battery_probe(struct platform_device *pdev)
{
	struct power_supply_config psy_cfg = {};
	struct rx51_device_info *di;
	int ret;

	di = devm_kzalloc(&pdev->dev, sizeof(*di), GFP_KERNEL);
	if (!di)
		return -ENOMEM;

	platform_set_drvdata(pdev, di);

	di->dev = &pdev->dev;
	di->bat_desc.name = "rx51-battery";
	di->bat_desc.type = POWER_SUPPLY_TYPE_BATTERY;
	di->bat_desc.properties = rx51_battery_props;
	di->bat_desc.num_properties = ARRAY_SIZE(rx51_battery_props);
	di->bat_desc.get_property = rx51_battery_get_property;

	psy_cfg.drv_data = di;

	di->channel_temp = iio_channel_get(di->dev, "temp");
	if (IS_ERR(di->channel_temp)) {
		ret = PTR_ERR(di->channel_temp);
		goto error;
	}

	di->channel_bsi  = iio_channel_get(di->dev, "bsi");
	if (IS_ERR(di->channel_bsi)) {
		ret = PTR_ERR(di->channel_bsi);
		goto error_channel_temp;
	}

	di->channel_vbat = iio_channel_get(di->dev, "vbat");
	if (IS_ERR(di->channel_vbat)) {
		ret = PTR_ERR(di->channel_vbat);
		goto error_channel_bsi;
	}

	di->bat = power_supply_register(di->dev, &di->bat_desc, &psy_cfg);
	if (IS_ERR(di->bat)) {
		ret = PTR_ERR(di->bat);
		goto error_channel_vbat;
	}

	return 0;

error_channel_vbat:
	iio_channel_release(di->channel_vbat);
error_channel_bsi:
	iio_channel_release(di->channel_bsi);
error_channel_temp:
	iio_channel_release(di->channel_temp);
error:

	return ret;
}

static int rx51_battery_remove(struct platform_device *pdev)
{
	struct rx51_device_info *di = platform_get_drvdata(pdev);

	power_supply_unregister(di->bat);

	iio_channel_release(di->channel_vbat);
	iio_channel_release(di->channel_bsi);
	iio_channel_release(di->channel_temp);

	return 0;
}

#ifdef CONFIG_OF
static const struct of_device_id n900_battery_of_match[] = {
	{.compatible = "nokia,n900-battery", },
	{ },
};
MODULE_DEVICE_TABLE(of, n900_battery_of_match);
#endif

static struct platform_driver rx51_battery_driver = {
	.probe = rx51_battery_probe,
	.remove = rx51_battery_remove,
	.driver = {
		.name = "rx51-battery",
		.of_match_table = of_match_ptr(n900_battery_of_match),
	},
};
module_platform_driver(rx51_battery_driver);

MODULE_ALIAS("platform:rx51-battery");
MODULE_AUTHOR("Pali Rohár <pali.rohar@gmail.com>");
MODULE_DESCRIPTION("Nokia RX-51 battery driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
04930baf PR	1	/*
	2	* Nokia RX-51 battery driver
	3	*
	4	* Copyright (C) 2012 Pali Rohár <pali.rohar@gmail.com>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License along
	17	* with this program; if not, write to the Free Software Foundation, Inc.,
	18	* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
	19	*/
	20
	21	#include <linux/module.h>
	22	#include <linux/param.h>
	23	#include <linux/platform_device.h>
	24	#include <linux/power_supply.h>
	25	#include <linux/slab.h>
	26	#include <linux/i2c/twl4030-madc.h>
57da5e86 SR	27	#include <linux/iio/consumer.h>
57da5e86 SR	28	#include <linux/of.h>
8e2747f0	29
04930baf PR	30	struct rx51_device_info {
04930baf PR	31	struct device *dev;
297d716f KK	32	struct power_supply *bat;
297d716f KK	33	struct power_supply_desc bat_desc;
57da5e86 SR	34	struct iio_channel *channel_temp;
	35	struct iio_channel *channel_bsi;
	36	struct iio_channel *channel_vbat;
04930baf PR	37	};
	38
	39	/*
	40	* Read ADCIN channel value, code copied from maemo kernel
	41	*/
57da5e86	42	static int rx51_battery_read_adc(struct iio_channel *channel)
04930baf	43	{
57da5e86 SR	44	int val, err;
	45	err = iio_read_channel_average_raw(channel, &val);
	46	if (err < 0)
	47	return err;
	48	return val;
04930baf PR	49	}
	50
	51	/*
	52	* Read ADCIN channel 12 (voltage) and convert RAW value to micro voltage
	53	* This conversion formula was extracted from maemo program bsi-read
	54	*/
	55	static int rx51_battery_read_voltage(struct rx51_device_info *di)
	56	{
57da5e86	57	int voltage = rx51_battery_read_adc(di->channel_vbat);
04930baf	58
57da5e86 SR	59	if (voltage < 0) {
57da5e86 SR	60	dev_err(di->dev, "Could not read ADC: %d\n", voltage);
04930baf	61	return voltage;
57da5e86	62	}
04930baf PR	63
	64	return 1000 * (10000 * voltage / 1705);
	65	}
	66
	67	/*
	68	* Temperature look-up tables
	69	* TEMP = (1/(t1 + 1/298) - 273.15)
	70	* Where t1 = (1/B) * ln((RAW_ADC_U * 2.5)/(R * I * 255))
	71	* Formula is based on experimental data, RX-51 CAL data, maemo program bme
	72	* and formula from da9052 driver with values R = 100, B = 3380, I = 0.00671
	73	*/
	74
	75	/*
	76	* Table1 (temperature for first 25 RAW values)
	77	* Usage: TEMP = rx51_temp_table1[RAW]
	78	* RAW is between 1 and 24
	79	* TEMP is between 201 C and 55 C
	80	*/
	81	static u8 rx51_temp_table1[] = {
	82	255, 201, 159, 138, 124, 114, 106, 99, 94, 89, 85, 82, 78, 75,
	83	73, 70, 68, 66, 64, 62, 61, 59, 57, 56, 55
	84	};
	85
	86	/*
	87	* Table2 (lowest RAW value for temperature)
	88	* Usage: RAW = rx51_temp_table2[TEMP-rx51_temp_table2_first]
	89	* TEMP is between 53 C and -32 C
	90	* RAW is between 25 and 993
	91	*/
	92	#define rx51_temp_table2_first 53
	93	static u16 rx51_temp_table2[] = {
	94	25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 39,
	95	40, 41, 43, 44, 46, 48, 49, 51, 53, 55, 57, 59, 61, 64,
	96	66, 69, 71, 74, 77, 80, 83, 86, 90, 94, 97, 101, 106, 110,
	97	115, 119, 125, 130, 136, 141, 148, 154, 161, 168, 176, 184, 202, 211,
	98	221, 231, 242, 254, 266, 279, 293, 308, 323, 340, 357, 375, 395, 415,
	99	437, 460, 485, 511, 539, 568, 600, 633, 669, 706, 747, 790, 836, 885,
	100	937, 993, 1024
	101	};
	102
	103	/*
	104	* Read ADCIN channel 0 (battery temp) and convert value to tenths of Celsius
	105	* Use Temperature look-up tables for conversation
	106	*/
	107	static int rx51_battery_read_temperature(struct rx51_device_info *di)
	108	{
	109	int min = 0;
	110	int max = ARRAY_SIZE(rx51_temp_table2) - 1;
57da5e86 SR	111	int raw = rx51_battery_read_adc(di->channel_temp);
	112
	113	if (raw < 0)
	114	dev_err(di->dev, "Could not read ADC: %d\n", raw);
04930baf PR	115
	116	/* Zero and negative values are undefined */
	117	if (raw <= 0)
	118	return INT_MAX;
	119
	120	/* ADC channels are 10 bit, higher value are undefined */
	121	if (raw >= (1 << 10))
	122	return INT_MIN;
	123
	124	/* First check for temperature in first direct table */
	125	if (raw < ARRAY_SIZE(rx51_temp_table1))
59584857	126	return rx51_temp_table1[raw] * 10;
04930baf PR	127
	128	/* Binary search RAW value in second inverse table */
	129	while (max - min > 1) {
	130	int mid = (max + min) / 2;
	131	if (rx51_temp_table2[mid] <= raw)
	132	min = mid;
	133	else if (rx51_temp_table2[mid] > raw)
	134	max = mid;
	135	if (rx51_temp_table2[mid] == raw)
	136	break;
	137	}
	138
59584857	139	return (rx51_temp_table2_first - min) * 10;
04930baf PR	140	}
	141
	142	/*
	143	* Read ADCIN channel 4 (BSI) and convert RAW value to micro Ah
	144	* This conversion formula was extracted from maemo program bsi-read
	145	*/
	146	static int rx51_battery_read_capacity(struct rx51_device_info *di)
	147	{
57da5e86	148	int capacity = rx51_battery_read_adc(di->channel_bsi);
04930baf	149
57da5e86 SR	150	if (capacity < 0) {
57da5e86 SR	151	dev_err(di->dev, "Could not read ADC: %d\n", capacity);
04930baf	152	return capacity;
57da5e86	153	}
04930baf PR	154
	155	return 1280 * (1200 * capacity)/(1024 - capacity);
	156	}
	157
	158	/*
	159	* Return power_supply property
	160	*/
	161	static int rx51_battery_get_property(struct power_supply *psy,
	162	enum power_supply_property psp,
	163	union power_supply_propval *val)
	164	{
297d716f	165	struct rx51_device_info *di = power_supply_get_drvdata(psy);
04930baf PR	166
	167	switch (psp) {
	168	case POWER_SUPPLY_PROP_TECHNOLOGY:
	169	val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
	170	break;
	171	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
	172	val->intval = 4200000;
	173	break;
	174	case POWER_SUPPLY_PROP_PRESENT:
	175	val->intval = rx51_battery_read_voltage(di) ? 1 : 0;
	176	break;
	177	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
	178	val->intval = rx51_battery_read_voltage(di);
	179	break;
	180	case POWER_SUPPLY_PROP_TEMP:
	181	val->intval = rx51_battery_read_temperature(di);
	182	break;
	183	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
	184	val->intval = rx51_battery_read_capacity(di);
	185	break;
	186	default:
	187	return -EINVAL;
	188	}
	189
	190	if (val->intval == INT_MAX \|\| val->intval == INT_MIN)
	191	return -EINVAL;
	192
	193	return 0;
	194	}
	195
	196	static enum power_supply_property rx51_battery_props[] = {
	197	POWER_SUPPLY_PROP_TECHNOLOGY,
	198	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
	199	POWER_SUPPLY_PROP_PRESENT,
	200	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	201	POWER_SUPPLY_PROP_TEMP,
	202	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
	203	};
	204
6d2cea4f	205	static int rx51_battery_probe(struct platform_device *pdev)
04930baf	206	{
297d716f	207	struct power_supply_config psy_cfg = {};
04930baf PR	208	struct rx51_device_info *di;
	209	int ret;
	210
b852ac51	211	di = devm_kzalloc(&pdev->dev, sizeof(*di), GFP_KERNEL);
04930baf PR	212	if (!di)
	213	return -ENOMEM;
	214
	215	platform_set_drvdata(pdev, di);
	216
57da5e86	217	di->dev = &pdev->dev;
b5e57863	218	di->bat_desc.name = "rx51-battery";
297d716f KK	219	di->bat_desc.type = POWER_SUPPLY_TYPE_BATTERY;
	220	di->bat_desc.properties = rx51_battery_props;
	221	di->bat_desc.num_properties = ARRAY_SIZE(rx51_battery_props);
	222	di->bat_desc.get_property = rx51_battery_get_property;
	223
	224	psy_cfg.drv_data = di;
04930baf	225
57da5e86 SR	226	di->channel_temp = iio_channel_get(di->dev, "temp");
	227	if (IS_ERR(di->channel_temp)) {
	228	ret = PTR_ERR(di->channel_temp);
	229	goto error;
	230	}
	231
	232	di->channel_bsi = iio_channel_get(di->dev, "bsi");
	233	if (IS_ERR(di->channel_bsi)) {
	234	ret = PTR_ERR(di->channel_bsi);
	235	goto error_channel_temp;
	236	}
	237
	238	di->channel_vbat = iio_channel_get(di->dev, "vbat");
	239	if (IS_ERR(di->channel_vbat)) {
	240	ret = PTR_ERR(di->channel_vbat);
	241	goto error_channel_bsi;
	242	}
	243
297d716f KK	244	di->bat = power_supply_register(di->dev, &di->bat_desc, &psy_cfg);
	245	if (IS_ERR(di->bat)) {
	246	ret = PTR_ERR(di->bat);
57da5e86	247	goto error_channel_vbat;
297d716f	248	}
04930baf PR	249
04930baf PR	250	return 0;
57da5e86 SR	251
	252	error_channel_vbat:
	253	iio_channel_release(di->channel_vbat);
	254	error_channel_bsi:
	255	iio_channel_release(di->channel_bsi);
	256	error_channel_temp:
	257	iio_channel_release(di->channel_temp);
	258	error:
	259
	260	return ret;
04930baf PR	261	}
04930baf PR	262
6d2cea4f	263	static int rx51_battery_remove(struct platform_device *pdev)
04930baf PR	264	{
	265	struct rx51_device_info *di = platform_get_drvdata(pdev);
	266
297d716f	267	power_supply_unregister(di->bat);
04930baf	268
57da5e86 SR	269	iio_channel_release(di->channel_vbat);
	270	iio_channel_release(di->channel_bsi);
	271	iio_channel_release(di->channel_temp);
	272
04930baf PR	273	return 0;
	274	}
	275
57da5e86 SR	276	#ifdef CONFIG_OF
	277	static const struct of_device_id n900_battery_of_match[] = {
	278	{.compatible = "nokia,n900-battery", },
	279	{ },
	280	};
	281	MODULE_DEVICE_TABLE(of, n900_battery_of_match);
	282	#endif
	283
04930baf PR	284	static struct platform_driver rx51_battery_driver = {
04930baf PR	285	.probe = rx51_battery_probe,
6d2cea4f	286	.remove = rx51_battery_remove,
04930baf PR	287	.driver = {
04930baf PR	288	.name = "rx51-battery",
57da5e86	289	.of_match_table = of_match_ptr(n900_battery_of_match),
04930baf PR	290	},
	291	};
	292	module_platform_driver(rx51_battery_driver);
	293
	294	MODULE_ALIAS("platform:rx51-battery");
	295	MODULE_AUTHOR("Pali Rohár <pali.rohar@gmail.com>");
	296	MODULE_DESCRIPTION("Nokia RX-51 battery driver");
	297	MODULE_LICENSE("GPL");