drivers/power/supply/rx51_battery.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Nokia RX-51 battery driver
  *
  * Copyright (C) 2012  Pali Rohár <pali@kernel.org>
  */

 #include <linux/module.h>
 #include <linux/param.h>
 #include <linux/platform_device.h>
 #include <linux/power_supply.h>
 #include <linux/slab.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@kernel.org>");
 MODULE_DESCRIPTION("Nokia RX-51 battery driver");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* Nokia RX-51 battery driver
	*
	* Copyright (C) 2012 Pali Rohár <pali@kernel.org>
	*/

	#include <linux/module.h>
	#include <linux/param.h>
	#include <linux/platform_device.h>
	#include <linux/power_supply.h>
	#include <linux/slab.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@kernel.org>");
	MODULE_DESCRIPTION("Nokia RX-51 battery driver");
	MODULE_LICENSE("GPL");