drivers/power/supply/max1720x_battery.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * Fuel gauge driver for Maxim 17201/17205
  *
  * based on max1721x_battery.c
  *
  * Copyright (C) 2024 Liebherr-Electronics and Drives GmbH
  */

 #include <linux/bitfield.h>
 #include <linux/i2c.h>
 #include <linux/module.h>
 #include <linux/nvmem-provider.h>
 #include <linux/power_supply.h>
 #include <linux/regmap.h>

 #include <linux/unaligned.h>

 /* Nonvolatile registers */
 #define MAX1720X_NXTABLE0		0x80
 #define MAX1720X_NRSENSE		0xCF	/* RSense in 10^-5 Ohm */
 #define MAX1720X_NDEVICE_NAME4		0xDF

 /* ModelGauge m5 */
 #define MAX172XX_STATUS			0x00	/* Status */
 #define MAX172XX_STATUS_BAT_ABSENT	BIT(3)	/* Battery absent */
 #define MAX172XX_REPCAP			0x05	/* Average capacity */
 #define MAX172XX_REPSOC			0x06	/* Percentage of charge */
 #define MAX172XX_TEMP			0x08	/* Temperature */
 #define MAX172XX_CURRENT		0x0A	/* Actual current */
 #define MAX172XX_AVG_CURRENT		0x0B	/* Average current */
 #define MAX172XX_TTE			0x11	/* Time to empty */
 #define MAX172XX_AVG_TA			0x16	/* Average temperature */
 #define MAX172XX_CYCLES			0x17
 #define MAX172XX_DESIGN_CAP		0x18	/* Design capacity */
 #define MAX172XX_AVG_VCELL		0x19
 #define MAX172XX_TTF			0x20	/* Time to full */
 #define MAX172XX_DEV_NAME		0x21	/* Device name */
 #define MAX172XX_DEV_NAME_TYPE_MASK	GENMASK(3, 0)
 #define MAX172XX_DEV_NAME_TYPE_MAX17201	BIT(0)
 #define MAX172XX_DEV_NAME_TYPE_MAX17205	(BIT(0) | BIT(2))
 #define MAX172XX_QR_TABLE10		0x22
 #define MAX172XX_BATT			0xDA	/* Battery voltage */
 #define MAX172XX_ATAVCAP		0xDF

 static const char *const max1720x_manufacturer = "Maxim Integrated";
 static const char *const max17201_model = "MAX17201";
 static const char *const max17205_model = "MAX17205";

 struct max1720x_device_info {
 	struct regmap *regmap;
 	struct regmap *regmap_nv;
 	struct i2c_client *ancillary;
 	int rsense;
 };

 /*
  * Model Gauge M5 Algorithm output register
  * Volatile data (must not be cached)
  */
 static const struct regmap_range max1720x_volatile_allow[] = {
 	regmap_reg_range(MAX172XX_STATUS, MAX172XX_CYCLES),
 	regmap_reg_range(MAX172XX_AVG_VCELL, MAX172XX_TTF),
 	regmap_reg_range(MAX172XX_QR_TABLE10, MAX172XX_ATAVCAP),
 };

 static const struct regmap_range max1720x_readable_allow[] = {
 	regmap_reg_range(MAX172XX_STATUS, MAX172XX_ATAVCAP),
 };

 static const struct regmap_range max1720x_readable_deny[] = {
 	/* unused registers */
 	regmap_reg_range(0x24, 0x26),
 	regmap_reg_range(0x30, 0x31),
 	regmap_reg_range(0x33, 0x34),
 	regmap_reg_range(0x37, 0x37),
 	regmap_reg_range(0x3B, 0x3C),
 	regmap_reg_range(0x40, 0x41),
 	regmap_reg_range(0x43, 0x44),
 	regmap_reg_range(0x47, 0x49),
 	regmap_reg_range(0x4B, 0x4C),
 	regmap_reg_range(0x4E, 0xAF),
 	regmap_reg_range(0xB1, 0xB3),
 	regmap_reg_range(0xB5, 0xB7),
 	regmap_reg_range(0xBF, 0xD0),
 	regmap_reg_range(0xDB, 0xDB),
 	regmap_reg_range(0xE0, 0xFF),
 };

 static const struct regmap_access_table max1720x_readable_regs = {
 	.yes_ranges	= max1720x_readable_allow,
 	.n_yes_ranges	= ARRAY_SIZE(max1720x_readable_allow),
 	.no_ranges	= max1720x_readable_deny,
 	.n_no_ranges	= ARRAY_SIZE(max1720x_readable_deny),
 };

 static const struct regmap_access_table max1720x_volatile_regs = {
 	.yes_ranges	= max1720x_volatile_allow,
 	.n_yes_ranges	= ARRAY_SIZE(max1720x_volatile_allow),
 	.no_ranges	= max1720x_readable_deny,
 	.n_no_ranges	= ARRAY_SIZE(max1720x_readable_deny),
 };

 static const struct regmap_config max1720x_regmap_cfg = {
 	.reg_bits = 8,
 	.val_bits = 16,
 	.max_register = MAX172XX_ATAVCAP,
 	.val_format_endian = REGMAP_ENDIAN_LITTLE,
 	.rd_table = &max1720x_readable_regs,
 	.volatile_table = &max1720x_volatile_regs,
 	.cache_type = REGCACHE_RBTREE,
 };

 static const struct regmap_range max1720x_nvmem_allow[] = {
 	regmap_reg_range(MAX1720X_NXTABLE0, MAX1720X_NDEVICE_NAME4),
 };

 static const struct regmap_range max1720x_nvmem_deny[] = {
 	regmap_reg_range(0x00, 0x7F),
 	regmap_reg_range(0xE0, 0xFF),
 };

 static const struct regmap_access_table max1720x_nvmem_regs = {
 	.yes_ranges	= max1720x_nvmem_allow,
 	.n_yes_ranges	= ARRAY_SIZE(max1720x_nvmem_allow),
 	.no_ranges	= max1720x_nvmem_deny,
 	.n_no_ranges	= ARRAY_SIZE(max1720x_nvmem_deny),
 };

 static const struct regmap_config max1720x_nvmem_regmap_cfg = {
 	.reg_bits = 8,
 	.val_bits = 16,
 	.max_register = MAX1720X_NDEVICE_NAME4,
 	.val_format_endian = REGMAP_ENDIAN_LITTLE,
 	.rd_table = &max1720x_nvmem_regs,
 };

 static const struct nvmem_cell_info max1720x_nvmem_cells[] = {
 	{ .name = "nXTable0",  .offset = 0,  .bytes = 2, },
 	{ .name = "nXTable1",  .offset = 2,  .bytes = 2, },
 	{ .name = "nXTable2",  .offset = 4,  .bytes = 2, },
 	{ .name = "nXTable3",  .offset = 6,  .bytes = 2, },
 	{ .name = "nXTable4",  .offset = 8,  .bytes = 2, },
 	{ .name = "nXTable5",  .offset = 10, .bytes = 2, },
 	{ .name = "nXTable6",  .offset = 12, .bytes = 2, },
 	{ .name = "nXTable7",  .offset = 14, .bytes = 2, },
 	{ .name = "nXTable8",  .offset = 16, .bytes = 2, },
 	{ .name = "nXTable9",  .offset = 18, .bytes = 2, },
 	{ .name = "nXTable10", .offset = 20, .bytes = 2, },
 	{ .name = "nXTable11", .offset = 22, .bytes = 2, },
 	{ .name = "nUser18C",  .offset = 24, .bytes = 2, },
 	{ .name = "nUser18D",  .offset = 26, .bytes = 2, },
 	{ .name = "nODSCTh",   .offset = 28, .bytes = 2, },
 	{ .name = "nODSCCfg",  .offset = 30, .bytes = 2, },

 	{ .name = "nOCVTable0",  .offset = 32, .bytes = 2, },
 	{ .name = "nOCVTable1",  .offset = 34, .bytes = 2, },
 	{ .name = "nOCVTable2",  .offset = 36, .bytes = 2, },
 	{ .name = "nOCVTable3",  .offset = 38, .bytes = 2, },
 	{ .name = "nOCVTable4",  .offset = 40, .bytes = 2, },
 	{ .name = "nOCVTable5",  .offset = 42, .bytes = 2, },
 	{ .name = "nOCVTable6",  .offset = 44, .bytes = 2, },
 	{ .name = "nOCVTable7",  .offset = 46, .bytes = 2, },
 	{ .name = "nOCVTable8",  .offset = 48, .bytes = 2, },
 	{ .name = "nOCVTable9",  .offset = 50, .bytes = 2, },
 	{ .name = "nOCVTable10", .offset = 52, .bytes = 2, },
 	{ .name = "nOCVTable11", .offset = 54, .bytes = 2, },
 	{ .name = "nIChgTerm",   .offset = 56, .bytes = 2, },
 	{ .name = "nFilterCfg",  .offset = 58, .bytes = 2, },
 	{ .name = "nVEmpty",     .offset = 60, .bytes = 2, },
 	{ .name = "nLearnCfg",   .offset = 62, .bytes = 2, },

 	{ .name = "nQRTable00",  .offset = 64, .bytes = 2, },
 	{ .name = "nQRTable10",  .offset = 66, .bytes = 2, },
 	{ .name = "nQRTable20",  .offset = 68, .bytes = 2, },
 	{ .name = "nQRTable30",  .offset = 70, .bytes = 2, },
 	{ .name = "nCycles",     .offset = 72, .bytes = 2, },
 	{ .name = "nFullCapNom", .offset = 74, .bytes = 2, },
 	{ .name = "nRComp0",     .offset = 76, .bytes = 2, },
 	{ .name = "nTempCo",     .offset = 78, .bytes = 2, },
 	{ .name = "nIAvgEmpty",  .offset = 80, .bytes = 2, },
 	{ .name = "nFullCapRep", .offset = 82, .bytes = 2, },
 	{ .name = "nVoltTemp",   .offset = 84, .bytes = 2, },
 	{ .name = "nMaxMinCurr", .offset = 86, .bytes = 2, },
 	{ .name = "nMaxMinVolt", .offset = 88, .bytes = 2, },
 	{ .name = "nMaxMinTemp", .offset = 90, .bytes = 2, },
 	{ .name = "nSOC",        .offset = 92, .bytes = 2, },
 	{ .name = "nTimerH",     .offset = 94, .bytes = 2, },

 	{ .name = "nConfig",    .offset = 96,  .bytes = 2, },
 	{ .name = "nRippleCfg", .offset = 98,  .bytes = 2, },
 	{ .name = "nMiscCfg",   .offset = 100, .bytes = 2, },
 	{ .name = "nDesignCap", .offset = 102, .bytes = 2, },
 	{ .name = "nHibCfg",    .offset = 104, .bytes = 2, },
 	{ .name = "nPackCfg",   .offset = 106, .bytes = 2, },
 	{ .name = "nRelaxCfg",  .offset = 108, .bytes = 2, },
 	{ .name = "nConvgCfg",  .offset = 110, .bytes = 2, },
 	{ .name = "nNVCfg0",    .offset = 112, .bytes = 2, },
 	{ .name = "nNVCfg1",    .offset = 114, .bytes = 2, },
 	{ .name = "nNVCfg2",    .offset = 116, .bytes = 2, },
 	{ .name = "nSBSCfg",    .offset = 118, .bytes = 2, },
 	{ .name = "nROMID0",    .offset = 120, .bytes = 2, },
 	{ .name = "nROMID1",    .offset = 122, .bytes = 2, },
 	{ .name = "nROMID2",    .offset = 124, .bytes = 2, },
 	{ .name = "nROMID3",    .offset = 126, .bytes = 2, },

 	{ .name = "nVAlrtTh",      .offset = 128, .bytes = 2, },
 	{ .name = "nTAlrtTh",      .offset = 130, .bytes = 2, },
 	{ .name = "nSAlrtTh",      .offset = 132, .bytes = 2, },
 	{ .name = "nIAlrtTh",      .offset = 134, .bytes = 2, },
 	{ .name = "nUser1C4",      .offset = 136, .bytes = 2, },
 	{ .name = "nUser1C5",      .offset = 138, .bytes = 2, },
 	{ .name = "nFullSOCThr",   .offset = 140, .bytes = 2, },
 	{ .name = "nTTFCfg",       .offset = 142, .bytes = 2, },
 	{ .name = "nCGain",        .offset = 144, .bytes = 2, },
 	{ .name = "nTCurve",       .offset = 146, .bytes = 2, },
 	{ .name = "nTGain",        .offset = 148, .bytes = 2, },
 	{ .name = "nTOff",         .offset = 150, .bytes = 2, },
 	{ .name = "nManfctrName0", .offset = 152, .bytes = 2, },
 	{ .name = "nManfctrName1", .offset = 154, .bytes = 2, },
 	{ .name = "nManfctrName2", .offset = 156, .bytes = 2, },
 	{ .name = "nRSense",       .offset = 158, .bytes = 2, },

 	{ .name = "nUser1D0",       .offset = 160, .bytes = 2, },
 	{ .name = "nUser1D1",       .offset = 162, .bytes = 2, },
 	{ .name = "nAgeFcCfg",      .offset = 164, .bytes = 2, },
 	{ .name = "nDesignVoltage", .offset = 166, .bytes = 2, },
 	{ .name = "nUser1D4",       .offset = 168, .bytes = 2, },
 	{ .name = "nRFastVShdn",    .offset = 170, .bytes = 2, },
 	{ .name = "nManfctrDate",   .offset = 172, .bytes = 2, },
 	{ .name = "nFirstUsed",     .offset = 174, .bytes = 2, },
 	{ .name = "nSerialNumber0", .offset = 176, .bytes = 2, },
 	{ .name = "nSerialNumber1", .offset = 178, .bytes = 2, },
 	{ .name = "nSerialNumber2", .offset = 180, .bytes = 2, },
 	{ .name = "nDeviceName0",   .offset = 182, .bytes = 2, },
 	{ .name = "nDeviceName1",   .offset = 184, .bytes = 2, },
 	{ .name = "nDeviceName2",   .offset = 186, .bytes = 2, },
 	{ .name = "nDeviceName3",   .offset = 188, .bytes = 2, },
 	{ .name = "nDeviceName4",   .offset = 190, .bytes = 2, },
 };

 static const enum power_supply_property max1720x_battery_props[] = {
 	POWER_SUPPLY_PROP_PRESENT,
 	POWER_SUPPLY_PROP_CAPACITY,
 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 	POWER_SUPPLY_PROP_CHARGE_AVG,
 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
 	POWER_SUPPLY_PROP_TIME_TO_FULL_AVG,
 	POWER_SUPPLY_PROP_TEMP,
 	POWER_SUPPLY_PROP_CURRENT_NOW,
 	POWER_SUPPLY_PROP_CURRENT_AVG,
 	POWER_SUPPLY_PROP_MODEL_NAME,
 	POWER_SUPPLY_PROP_MANUFACTURER,
 };

 /* Convert regs value to power_supply units */

 static int max172xx_time_to_ps(unsigned int reg)
 {
 	return reg * 5625 / 1000;	/* in sec. */
 }

 static int max172xx_percent_to_ps(unsigned int reg)
 {
 	return reg / 256;	/* in percent from 0 to 100 */
 }

 static int max172xx_voltage_to_ps(unsigned int reg)
 {
 	return reg * 1250;	/* in uV */
 }

 static int max172xx_capacity_to_ps(unsigned int reg)
 {
 	return reg * 500;	/* in uAh */
 }

 /*
  * Current and temperature is signed values, so unsigned regs
  * value must be converted to signed type
  */

 static int max172xx_temperature_to_ps(unsigned int reg)
 {
 	int val = (int16_t)reg;

 	return val * 10 / 256; /* in tenths of deg. C */
 }

 /*
  * Calculating current registers resolution:
  *
  * RSense stored in 10^-5 Ohm, so mesaurment voltage must be
  * in 10^-11 Volts for get current in uA.
  * 16 bit current reg fullscale +/-51.2mV is 102400 uV.
  * So: 102400 / 65535 * 10^5 = 156252
  */
 static int max172xx_current_to_voltage(unsigned int reg)
 {
 	int val = (int16_t)reg;

 	return val * 156252;
 }

 static int max1720x_battery_get_property(struct power_supply *psy,
 					 enum power_supply_property psp,
 					 union power_supply_propval *val)
 {
 	struct max1720x_device_info *info = power_supply_get_drvdata(psy);
 	unsigned int reg_val;
 	int ret = 0;

 	switch (psp) {
 	case POWER_SUPPLY_PROP_PRESENT:
 		/*
 		 * POWER_SUPPLY_PROP_PRESENT will always readable via
 		 * sysfs interface. Value return 0 if battery not
 		 * present or unaccesable via I2c.
 		 */
 		ret = regmap_read(info->regmap, MAX172XX_STATUS, &reg_val);
 		if (ret < 0) {
 			val->intval = 0;
 			return 0;
 		}

 		val->intval = !FIELD_GET(MAX172XX_STATUS_BAT_ABSENT, reg_val);
 		break;
 	case POWER_SUPPLY_PROP_CAPACITY:
 		ret = regmap_read(info->regmap, MAX172XX_REPSOC, &reg_val);
 		val->intval = max172xx_percent_to_ps(reg_val);
 		break;
 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 		ret = regmap_read(info->regmap, MAX172XX_BATT, &reg_val);
 		val->intval = max172xx_voltage_to_ps(reg_val);
 		break;
 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 		ret = regmap_read(info->regmap, MAX172XX_DESIGN_CAP, &reg_val);
 		val->intval = max172xx_capacity_to_ps(reg_val);
 		break;
 	case POWER_SUPPLY_PROP_CHARGE_AVG:
 		ret = regmap_read(info->regmap, MAX172XX_REPCAP, &reg_val);
 		val->intval = max172xx_capacity_to_ps(reg_val);
 		break;
 	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
 		ret = regmap_read(info->regmap, MAX172XX_TTE, &reg_val);
 		val->intval = max172xx_time_to_ps(reg_val);
 		break;
 	case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
 		ret = regmap_read(info->regmap, MAX172XX_TTF, &reg_val);
 		val->intval = max172xx_time_to_ps(reg_val);
 		break;
 	case POWER_SUPPLY_PROP_TEMP:
 		ret = regmap_read(info->regmap, MAX172XX_TEMP, &reg_val);
 		val->intval = max172xx_temperature_to_ps(reg_val);
 		break;
 	case POWER_SUPPLY_PROP_CURRENT_NOW:
 		ret = regmap_read(info->regmap, MAX172XX_CURRENT, &reg_val);
 		val->intval = max172xx_current_to_voltage(reg_val) / info->rsense;
 		break;
 	case POWER_SUPPLY_PROP_CURRENT_AVG:
 		ret = regmap_read(info->regmap, MAX172XX_AVG_CURRENT, &reg_val);
 		val->intval = max172xx_current_to_voltage(reg_val) / info->rsense;
 		break;
 	case POWER_SUPPLY_PROP_MODEL_NAME:
 		ret = regmap_read(info->regmap, MAX172XX_DEV_NAME, &reg_val);
 		reg_val = FIELD_GET(MAX172XX_DEV_NAME_TYPE_MASK, reg_val);
 		if (reg_val == MAX172XX_DEV_NAME_TYPE_MAX17201)
 			val->strval = max17201_model;
 		else if (reg_val == MAX172XX_DEV_NAME_TYPE_MAX17205)
 			val->strval = max17205_model;
 		else
 			return -ENODEV;
 		break;
 	case POWER_SUPPLY_PROP_MANUFACTURER:
 		val->strval = max1720x_manufacturer;
 		break;
 	default:
 		return -EINVAL;
 	}

 	return ret;
 }

 static
 int max1720x_nvmem_reg_read(void *priv, unsigned int off, void *val, size_t len)
 {
 	struct max1720x_device_info *info = priv;
 	unsigned int reg = MAX1720X_NXTABLE0 + (off / 2);

 	return regmap_bulk_read(info->regmap_nv, reg, val, len / 2);
 }

 static void max1720x_unregister_ancillary(void *data)
 {
 	struct max1720x_device_info *info = data;

 	i2c_unregister_device(info->ancillary);
 }

 static int max1720x_probe_nvmem(struct i2c_client *client,
 				struct max1720x_device_info *info)
 {
 	struct device *dev = &client->dev;
 	struct nvmem_config nvmem_config = {
 		.dev = dev,
 		.name = "max1720x_nvmem",
 		.cells = max1720x_nvmem_cells,
 		.ncells = ARRAY_SIZE(max1720x_nvmem_cells),
 		.read_only = true,
 		.root_only = true,
 		.reg_read = max1720x_nvmem_reg_read,
 		.size = ARRAY_SIZE(max1720x_nvmem_cells) * 2,
 		.word_size = 2,
 		.stride = 2,
 		.priv = info,
 	};
 	struct nvmem_device *nvmem;
 	unsigned int val;
 	int ret;

 	info->ancillary = i2c_new_ancillary_device(client, "nvmem", 0xb);
 	if (IS_ERR(info->ancillary)) {
 		dev_err(dev, "Failed to initialize ancillary i2c device\n");
 		return PTR_ERR(info->ancillary);
 	}

 	ret = devm_add_action_or_reset(dev, max1720x_unregister_ancillary, info);
 	if (ret) {
 		dev_err(dev, "Failed to add unregister callback\n");
 		return ret;
 	}

 	info->regmap_nv = devm_regmap_init_i2c(info->ancillary,
 					       &max1720x_nvmem_regmap_cfg);
 	if (IS_ERR(info->regmap_nv)) {
 		dev_err(dev, "regmap initialization of nvmem failed\n");
 		return PTR_ERR(info->regmap_nv);
 	}

 	ret = regmap_read(info->regmap_nv, MAX1720X_NRSENSE, &val);
 	if (ret < 0) {
 		dev_err(dev, "Failed to read sense resistor value\n");
 		return ret;
 	}

 	info->rsense = val;
 	if (!info->rsense) {
 		dev_warn(dev, "RSense not calibrated, set 10 mOhms!\n");
 		info->rsense = 1000; /* in regs in 10^-5 */
 	}

 	nvmem = devm_nvmem_register(dev, &nvmem_config);
 	if (IS_ERR(nvmem)) {
 		dev_err(dev, "Could not register nvmem!");
 		return PTR_ERR(nvmem);
 	}

 	return 0;
 }

 static const struct power_supply_desc max1720x_bat_desc = {
 	.name = "max1720x",
 	.no_thermal = true,
 	.type = POWER_SUPPLY_TYPE_BATTERY,
 	.properties = max1720x_battery_props,
 	.num_properties = ARRAY_SIZE(max1720x_battery_props),
 	.get_property = max1720x_battery_get_property,
 };

 static int max1720x_probe(struct i2c_client *client)
 {
 	struct power_supply_config psy_cfg = {};
 	struct device *dev = &client->dev;
 	struct max1720x_device_info *info;
 	struct power_supply *bat;
 	int ret;

 	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
 	if (!info)
 		return -ENOMEM;

 	psy_cfg.drv_data = info;
 	psy_cfg.fwnode = dev_fwnode(dev);
 	i2c_set_clientdata(client, info);
 	info->regmap = devm_regmap_init_i2c(client, &max1720x_regmap_cfg);
 	if (IS_ERR(info->regmap))
 		return dev_err_probe(dev, PTR_ERR(info->regmap),
 				     "regmap initialization failed\n");

 	ret = max1720x_probe_nvmem(client, info);
 	if (ret)
 		return dev_err_probe(dev, ret, "Failed to probe nvmem\n");

 	bat = devm_power_supply_register(dev, &max1720x_bat_desc, &psy_cfg);
 	if (IS_ERR(bat))
 		return dev_err_probe(dev, PTR_ERR(bat),
 				     "Failed to register power supply\n");

 	return 0;
 }

 static const struct of_device_id max1720x_of_match[] = {
 	{ .compatible = "maxim,max17201" },
 	{}
 };
 MODULE_DEVICE_TABLE(of, max1720x_of_match);

 static struct i2c_driver max1720x_i2c_driver = {
 	.driver = {
 		.name = "max1720x",
 		.of_match_table = max1720x_of_match,
 	},
 	.probe = max1720x_probe,
 };
 module_i2c_driver(max1720x_i2c_driver);

 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Dimitri Fedrau <dima.fedrau@gmail.com>");
 MODULE_DESCRIPTION("Maxim MAX17201/MAX17205 Fuel Gauge IC driver");
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* Fuel gauge driver for Maxim 17201/17205
	*
	* based on max1721x_battery.c
	*
	* Copyright (C) 2024 Liebherr-Electronics and Drives GmbH
	*/

	#include <linux/bitfield.h>
	#include <linux/i2c.h>
	#include <linux/module.h>
	#include <linux/nvmem-provider.h>
	#include <linux/power_supply.h>
	#include <linux/regmap.h>

	#include <linux/unaligned.h>

	/* Nonvolatile registers */
	#define MAX1720X_NXTABLE0 0x80
	#define MAX1720X_NRSENSE 0xCF /* RSense in 10^-5 Ohm */
	#define MAX1720X_NDEVICE_NAME4 0xDF

	/* ModelGauge m5 */
	#define MAX172XX_STATUS 0x00 /* Status */
	#define MAX172XX_STATUS_BAT_ABSENT BIT(3) /* Battery absent */
	#define MAX172XX_REPCAP 0x05 /* Average capacity */
	#define MAX172XX_REPSOC 0x06 /* Percentage of charge */
	#define MAX172XX_TEMP 0x08 /* Temperature */
	#define MAX172XX_CURRENT 0x0A /* Actual current */
	#define MAX172XX_AVG_CURRENT 0x0B /* Average current */
	#define MAX172XX_TTE 0x11 /* Time to empty */
	#define MAX172XX_AVG_TA 0x16 /* Average temperature */
	#define MAX172XX_CYCLES 0x17
	#define MAX172XX_DESIGN_CAP 0x18 /* Design capacity */
	#define MAX172XX_AVG_VCELL 0x19
	#define MAX172XX_TTF 0x20 /* Time to full */
	#define MAX172XX_DEV_NAME 0x21 /* Device name */
	#define MAX172XX_DEV_NAME_TYPE_MASK GENMASK(3, 0)
	#define MAX172XX_DEV_NAME_TYPE_MAX17201 BIT(0)
	#define MAX172XX_DEV_NAME_TYPE_MAX17205 (BIT(0) \| BIT(2))
	#define MAX172XX_QR_TABLE10 0x22
	#define MAX172XX_BATT 0xDA /* Battery voltage */
	#define MAX172XX_ATAVCAP 0xDF

	static const char *const max1720x_manufacturer = "Maxim Integrated";
	static const char *const max17201_model = "MAX17201";
	static const char *const max17205_model = "MAX17205";

	struct max1720x_device_info {
	struct regmap *regmap;
	struct regmap *regmap_nv;
	struct i2c_client *ancillary;
	int rsense;
	};

	/*
	* Model Gauge M5 Algorithm output register
	* Volatile data (must not be cached)
	*/
	static const struct regmap_range max1720x_volatile_allow[] = {
	regmap_reg_range(MAX172XX_STATUS, MAX172XX_CYCLES),
	regmap_reg_range(MAX172XX_AVG_VCELL, MAX172XX_TTF),
	regmap_reg_range(MAX172XX_QR_TABLE10, MAX172XX_ATAVCAP),
	};

	static const struct regmap_range max1720x_readable_allow[] = {
	regmap_reg_range(MAX172XX_STATUS, MAX172XX_ATAVCAP),
	};

	static const struct regmap_range max1720x_readable_deny[] = {
	/* unused registers */
	regmap_reg_range(0x24, 0x26),
	regmap_reg_range(0x30, 0x31),
	regmap_reg_range(0x33, 0x34),
	regmap_reg_range(0x37, 0x37),
	regmap_reg_range(0x3B, 0x3C),
	regmap_reg_range(0x40, 0x41),
	regmap_reg_range(0x43, 0x44),
	regmap_reg_range(0x47, 0x49),
	regmap_reg_range(0x4B, 0x4C),
	regmap_reg_range(0x4E, 0xAF),
	regmap_reg_range(0xB1, 0xB3),
	regmap_reg_range(0xB5, 0xB7),
	regmap_reg_range(0xBF, 0xD0),
	regmap_reg_range(0xDB, 0xDB),
	regmap_reg_range(0xE0, 0xFF),
	};

	static const struct regmap_access_table max1720x_readable_regs = {
	.yes_ranges = max1720x_readable_allow,
	.n_yes_ranges = ARRAY_SIZE(max1720x_readable_allow),
	.no_ranges = max1720x_readable_deny,
	.n_no_ranges = ARRAY_SIZE(max1720x_readable_deny),
	};

	static const struct regmap_access_table max1720x_volatile_regs = {
	.yes_ranges = max1720x_volatile_allow,
	.n_yes_ranges = ARRAY_SIZE(max1720x_volatile_allow),
	.no_ranges = max1720x_readable_deny,
	.n_no_ranges = ARRAY_SIZE(max1720x_readable_deny),
	};

	static const struct regmap_config max1720x_regmap_cfg = {
	.reg_bits = 8,
	.val_bits = 16,
	.max_register = MAX172XX_ATAVCAP,
	.val_format_endian = REGMAP_ENDIAN_LITTLE,
	.rd_table = &max1720x_readable_regs,
	.volatile_table = &max1720x_volatile_regs,
	.cache_type = REGCACHE_RBTREE,
	};

	static const struct regmap_range max1720x_nvmem_allow[] = {
	regmap_reg_range(MAX1720X_NXTABLE0, MAX1720X_NDEVICE_NAME4),
	};

	static const struct regmap_range max1720x_nvmem_deny[] = {
	regmap_reg_range(0x00, 0x7F),
	regmap_reg_range(0xE0, 0xFF),
	};

	static const struct regmap_access_table max1720x_nvmem_regs = {
	.yes_ranges = max1720x_nvmem_allow,
	.n_yes_ranges = ARRAY_SIZE(max1720x_nvmem_allow),
	.no_ranges = max1720x_nvmem_deny,
	.n_no_ranges = ARRAY_SIZE(max1720x_nvmem_deny),
	};

	static const struct regmap_config max1720x_nvmem_regmap_cfg = {
	.reg_bits = 8,
	.val_bits = 16,
	.max_register = MAX1720X_NDEVICE_NAME4,
	.val_format_endian = REGMAP_ENDIAN_LITTLE,
	.rd_table = &max1720x_nvmem_regs,
	};

	static const struct nvmem_cell_info max1720x_nvmem_cells[] = {
	{ .name = "nXTable0", .offset = 0, .bytes = 2, },
	{ .name = "nXTable1", .offset = 2, .bytes = 2, },
	{ .name = "nXTable2", .offset = 4, .bytes = 2, },
	{ .name = "nXTable3", .offset = 6, .bytes = 2, },
	{ .name = "nXTable4", .offset = 8, .bytes = 2, },
	{ .name = "nXTable5", .offset = 10, .bytes = 2, },
	{ .name = "nXTable6", .offset = 12, .bytes = 2, },
	{ .name = "nXTable7", .offset = 14, .bytes = 2, },
	{ .name = "nXTable8", .offset = 16, .bytes = 2, },
	{ .name = "nXTable9", .offset = 18, .bytes = 2, },
	{ .name = "nXTable10", .offset = 20, .bytes = 2, },
	{ .name = "nXTable11", .offset = 22, .bytes = 2, },
	{ .name = "nUser18C", .offset = 24, .bytes = 2, },
	{ .name = "nUser18D", .offset = 26, .bytes = 2, },
	{ .name = "nODSCTh", .offset = 28, .bytes = 2, },
	{ .name = "nODSCCfg", .offset = 30, .bytes = 2, },

	{ .name = "nOCVTable0", .offset = 32, .bytes = 2, },
	{ .name = "nOCVTable1", .offset = 34, .bytes = 2, },
	{ .name = "nOCVTable2", .offset = 36, .bytes = 2, },
	{ .name = "nOCVTable3", .offset = 38, .bytes = 2, },
	{ .name = "nOCVTable4", .offset = 40, .bytes = 2, },
	{ .name = "nOCVTable5", .offset = 42, .bytes = 2, },
	{ .name = "nOCVTable6", .offset = 44, .bytes = 2, },
	{ .name = "nOCVTable7", .offset = 46, .bytes = 2, },
	{ .name = "nOCVTable8", .offset = 48, .bytes = 2, },
	{ .name = "nOCVTable9", .offset = 50, .bytes = 2, },
	{ .name = "nOCVTable10", .offset = 52, .bytes = 2, },
	{ .name = "nOCVTable11", .offset = 54, .bytes = 2, },
	{ .name = "nIChgTerm", .offset = 56, .bytes = 2, },
	{ .name = "nFilterCfg", .offset = 58, .bytes = 2, },
	{ .name = "nVEmpty", .offset = 60, .bytes = 2, },
	{ .name = "nLearnCfg", .offset = 62, .bytes = 2, },

	{ .name = "nQRTable00", .offset = 64, .bytes = 2, },
	{ .name = "nQRTable10", .offset = 66, .bytes = 2, },
	{ .name = "nQRTable20", .offset = 68, .bytes = 2, },
	{ .name = "nQRTable30", .offset = 70, .bytes = 2, },
	{ .name = "nCycles", .offset = 72, .bytes = 2, },
	{ .name = "nFullCapNom", .offset = 74, .bytes = 2, },
	{ .name = "nRComp0", .offset = 76, .bytes = 2, },
	{ .name = "nTempCo", .offset = 78, .bytes = 2, },
	{ .name = "nIAvgEmpty", .offset = 80, .bytes = 2, },
	{ .name = "nFullCapRep", .offset = 82, .bytes = 2, },
	{ .name = "nVoltTemp", .offset = 84, .bytes = 2, },
	{ .name = "nMaxMinCurr", .offset = 86, .bytes = 2, },
	{ .name = "nMaxMinVolt", .offset = 88, .bytes = 2, },
	{ .name = "nMaxMinTemp", .offset = 90, .bytes = 2, },
	{ .name = "nSOC", .offset = 92, .bytes = 2, },
	{ .name = "nTimerH", .offset = 94, .bytes = 2, },

	{ .name = "nConfig", .offset = 96, .bytes = 2, },
	{ .name = "nRippleCfg", .offset = 98, .bytes = 2, },
	{ .name = "nMiscCfg", .offset = 100, .bytes = 2, },
	{ .name = "nDesignCap", .offset = 102, .bytes = 2, },
	{ .name = "nHibCfg", .offset = 104, .bytes = 2, },
	{ .name = "nPackCfg", .offset = 106, .bytes = 2, },
	{ .name = "nRelaxCfg", .offset = 108, .bytes = 2, },
	{ .name = "nConvgCfg", .offset = 110, .bytes = 2, },
	{ .name = "nNVCfg0", .offset = 112, .bytes = 2, },
	{ .name = "nNVCfg1", .offset = 114, .bytes = 2, },
	{ .name = "nNVCfg2", .offset = 116, .bytes = 2, },
	{ .name = "nSBSCfg", .offset = 118, .bytes = 2, },
	{ .name = "nROMID0", .offset = 120, .bytes = 2, },
	{ .name = "nROMID1", .offset = 122, .bytes = 2, },
	{ .name = "nROMID2", .offset = 124, .bytes = 2, },
	{ .name = "nROMID3", .offset = 126, .bytes = 2, },

	{ .name = "nVAlrtTh", .offset = 128, .bytes = 2, },
	{ .name = "nTAlrtTh", .offset = 130, .bytes = 2, },
	{ .name = "nSAlrtTh", .offset = 132, .bytes = 2, },
	{ .name = "nIAlrtTh", .offset = 134, .bytes = 2, },
	{ .name = "nUser1C4", .offset = 136, .bytes = 2, },
	{ .name = "nUser1C5", .offset = 138, .bytes = 2, },
	{ .name = "nFullSOCThr", .offset = 140, .bytes = 2, },
	{ .name = "nTTFCfg", .offset = 142, .bytes = 2, },
	{ .name = "nCGain", .offset = 144, .bytes = 2, },
	{ .name = "nTCurve", .offset = 146, .bytes = 2, },
	{ .name = "nTGain", .offset = 148, .bytes = 2, },
	{ .name = "nTOff", .offset = 150, .bytes = 2, },
	{ .name = "nManfctrName0", .offset = 152, .bytes = 2, },
	{ .name = "nManfctrName1", .offset = 154, .bytes = 2, },
	{ .name = "nManfctrName2", .offset = 156, .bytes = 2, },
	{ .name = "nRSense", .offset = 158, .bytes = 2, },

	{ .name = "nUser1D0", .offset = 160, .bytes = 2, },
	{ .name = "nUser1D1", .offset = 162, .bytes = 2, },
	{ .name = "nAgeFcCfg", .offset = 164, .bytes = 2, },
	{ .name = "nDesignVoltage", .offset = 166, .bytes = 2, },
	{ .name = "nUser1D4", .offset = 168, .bytes = 2, },
	{ .name = "nRFastVShdn", .offset = 170, .bytes = 2, },
	{ .name = "nManfctrDate", .offset = 172, .bytes = 2, },
	{ .name = "nFirstUsed", .offset = 174, .bytes = 2, },
	{ .name = "nSerialNumber0", .offset = 176, .bytes = 2, },
	{ .name = "nSerialNumber1", .offset = 178, .bytes = 2, },
	{ .name = "nSerialNumber2", .offset = 180, .bytes = 2, },
	{ .name = "nDeviceName0", .offset = 182, .bytes = 2, },
	{ .name = "nDeviceName1", .offset = 184, .bytes = 2, },
	{ .name = "nDeviceName2", .offset = 186, .bytes = 2, },
	{ .name = "nDeviceName3", .offset = 188, .bytes = 2, },
	{ .name = "nDeviceName4", .offset = 190, .bytes = 2, },
	};

	static const enum power_supply_property max1720x_battery_props[] = {
	POWER_SUPPLY_PROP_PRESENT,
	POWER_SUPPLY_PROP_CAPACITY,
	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
	POWER_SUPPLY_PROP_CHARGE_AVG,
	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
	POWER_SUPPLY_PROP_TIME_TO_FULL_AVG,
	POWER_SUPPLY_PROP_TEMP,
	POWER_SUPPLY_PROP_CURRENT_NOW,
	POWER_SUPPLY_PROP_CURRENT_AVG,
	POWER_SUPPLY_PROP_MODEL_NAME,
	POWER_SUPPLY_PROP_MANUFACTURER,
	};

	/* Convert regs value to power_supply units */

	static int max172xx_time_to_ps(unsigned int reg)
	{
	return reg * 5625 / 1000; /* in sec. */
	}

	static int max172xx_percent_to_ps(unsigned int reg)
	{
	return reg / 256; /* in percent from 0 to 100 */
	}

	static int max172xx_voltage_to_ps(unsigned int reg)
	{
	return reg * 1250; /* in uV */
	}

	static int max172xx_capacity_to_ps(unsigned int reg)
	{
	return reg * 500; /* in uAh */
	}

	/*
	* Current and temperature is signed values, so unsigned regs
	* value must be converted to signed type
	*/

	static int max172xx_temperature_to_ps(unsigned int reg)
	{
	int val = (int16_t)reg;

	return val * 10 / 256; /* in tenths of deg. C */
	}

	/*
	* Calculating current registers resolution:
	*
	* RSense stored in 10^-5 Ohm, so mesaurment voltage must be
	* in 10^-11 Volts for get current in uA.
	* 16 bit current reg fullscale +/-51.2mV is 102400 uV.
	* So: 102400 / 65535 * 10^5 = 156252
	*/
	static int max172xx_current_to_voltage(unsigned int reg)
	{
	int val = (int16_t)reg;

	return val * 156252;
	}

	static int max1720x_battery_get_property(struct power_supply *psy,
	enum power_supply_property psp,
	union power_supply_propval *val)
	{
	struct max1720x_device_info *info = power_supply_get_drvdata(psy);
	unsigned int reg_val;
	int ret = 0;

	switch (psp) {
	case POWER_SUPPLY_PROP_PRESENT:
	/*
	* POWER_SUPPLY_PROP_PRESENT will always readable via
	* sysfs interface. Value return 0 if battery not
	* present or unaccesable via I2c.
	*/
	ret = regmap_read(info->regmap, MAX172XX_STATUS, &reg_val);
	if (ret < 0) {
	val->intval = 0;
	return 0;
	}

	val->intval = !FIELD_GET(MAX172XX_STATUS_BAT_ABSENT, reg_val);
	break;
	case POWER_SUPPLY_PROP_CAPACITY:
	ret = regmap_read(info->regmap, MAX172XX_REPSOC, &reg_val);
	val->intval = max172xx_percent_to_ps(reg_val);
	break;
	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
	ret = regmap_read(info->regmap, MAX172XX_BATT, &reg_val);
	val->intval = max172xx_voltage_to_ps(reg_val);
	break;
	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
	ret = regmap_read(info->regmap, MAX172XX_DESIGN_CAP, &reg_val);
	val->intval = max172xx_capacity_to_ps(reg_val);
	break;
	case POWER_SUPPLY_PROP_CHARGE_AVG:
	ret = regmap_read(info->regmap, MAX172XX_REPCAP, &reg_val);
	val->intval = max172xx_capacity_to_ps(reg_val);
	break;
	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
	ret = regmap_read(info->regmap, MAX172XX_TTE, &reg_val);
	val->intval = max172xx_time_to_ps(reg_val);
	break;
	case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
	ret = regmap_read(info->regmap, MAX172XX_TTF, &reg_val);
	val->intval = max172xx_time_to_ps(reg_val);
	break;
	case POWER_SUPPLY_PROP_TEMP:
	ret = regmap_read(info->regmap, MAX172XX_TEMP, &reg_val);
	val->intval = max172xx_temperature_to_ps(reg_val);
	break;
	case POWER_SUPPLY_PROP_CURRENT_NOW:
	ret = regmap_read(info->regmap, MAX172XX_CURRENT, &reg_val);
	val->intval = max172xx_current_to_voltage(reg_val) / info->rsense;
	break;
	case POWER_SUPPLY_PROP_CURRENT_AVG:
	ret = regmap_read(info->regmap, MAX172XX_AVG_CURRENT, &reg_val);
	val->intval = max172xx_current_to_voltage(reg_val) / info->rsense;
	break;
	case POWER_SUPPLY_PROP_MODEL_NAME:
	ret = regmap_read(info->regmap, MAX172XX_DEV_NAME, &reg_val);
	reg_val = FIELD_GET(MAX172XX_DEV_NAME_TYPE_MASK, reg_val);
	if (reg_val == MAX172XX_DEV_NAME_TYPE_MAX17201)
	val->strval = max17201_model;
	else if (reg_val == MAX172XX_DEV_NAME_TYPE_MAX17205)
	val->strval = max17205_model;
	else
	return -ENODEV;
	break;
	case POWER_SUPPLY_PROP_MANUFACTURER:
	val->strval = max1720x_manufacturer;
	break;
	default:
	return -EINVAL;
	}

	return ret;
	}

	static
	int max1720x_nvmem_reg_read(void priv, unsigned int off, void val, size_t len)
	{
	struct max1720x_device_info *info = priv;
	unsigned int reg = MAX1720X_NXTABLE0 + (off / 2);

	return regmap_bulk_read(info->regmap_nv, reg, val, len / 2);
	}

	static void max1720x_unregister_ancillary(void *data)
	{
	struct max1720x_device_info *info = data;

	i2c_unregister_device(info->ancillary);
	}

	static int max1720x_probe_nvmem(struct i2c_client *client,
	struct max1720x_device_info *info)
	{
	struct device *dev = &client->dev;
	struct nvmem_config nvmem_config = {
	.dev = dev,
	.name = "max1720x_nvmem",
	.cells = max1720x_nvmem_cells,
	.ncells = ARRAY_SIZE(max1720x_nvmem_cells),
	.read_only = true,
	.root_only = true,
	.reg_read = max1720x_nvmem_reg_read,
	.size = ARRAY_SIZE(max1720x_nvmem_cells) * 2,
	.word_size = 2,
	.stride = 2,
	.priv = info,
	};
	struct nvmem_device *nvmem;
	unsigned int val;
	int ret;

	info->ancillary = i2c_new_ancillary_device(client, "nvmem", 0xb);
	if (IS_ERR(info->ancillary)) {
	dev_err(dev, "Failed to initialize ancillary i2c device\n");
	return PTR_ERR(info->ancillary);
	}

	ret = devm_add_action_or_reset(dev, max1720x_unregister_ancillary, info);
	if (ret) {
	dev_err(dev, "Failed to add unregister callback\n");
	return ret;
	}

	info->regmap_nv = devm_regmap_init_i2c(info->ancillary,
	&max1720x_nvmem_regmap_cfg);
	if (IS_ERR(info->regmap_nv)) {
	dev_err(dev, "regmap initialization of nvmem failed\n");
	return PTR_ERR(info->regmap_nv);
	}

	ret = regmap_read(info->regmap_nv, MAX1720X_NRSENSE, &val);
	if (ret < 0) {
	dev_err(dev, "Failed to read sense resistor value\n");
	return ret;
	}

	info->rsense = val;
	if (!info->rsense) {
	dev_warn(dev, "RSense not calibrated, set 10 mOhms!\n");
	info->rsense = 1000; /* in regs in 10^-5 */
	}

	nvmem = devm_nvmem_register(dev, &nvmem_config);
	if (IS_ERR(nvmem)) {
	dev_err(dev, "Could not register nvmem!");
	return PTR_ERR(nvmem);
	}

	return 0;
	}

	static const struct power_supply_desc max1720x_bat_desc = {
	.name = "max1720x",
	.no_thermal = true,
	.type = POWER_SUPPLY_TYPE_BATTERY,
	.properties = max1720x_battery_props,
	.num_properties = ARRAY_SIZE(max1720x_battery_props),
	.get_property = max1720x_battery_get_property,
	};

	static int max1720x_probe(struct i2c_client *client)
	{
	struct power_supply_config psy_cfg = {};
	struct device *dev = &client->dev;
	struct max1720x_device_info *info;
	struct power_supply *bat;
	int ret;

	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
	if (!info)
	return -ENOMEM;

	psy_cfg.drv_data = info;
	psy_cfg.fwnode = dev_fwnode(dev);
	i2c_set_clientdata(client, info);
	info->regmap = devm_regmap_init_i2c(client, &max1720x_regmap_cfg);
	if (IS_ERR(info->regmap))
	return dev_err_probe(dev, PTR_ERR(info->regmap),
	"regmap initialization failed\n");

	ret = max1720x_probe_nvmem(client, info);
	if (ret)
	return dev_err_probe(dev, ret, "Failed to probe nvmem\n");

	bat = devm_power_supply_register(dev, &max1720x_bat_desc, &psy_cfg);
	if (IS_ERR(bat))
	return dev_err_probe(dev, PTR_ERR(bat),
	"Failed to register power supply\n");

	return 0;
	}

	static const struct of_device_id max1720x_of_match[] = {
	{ .compatible = "maxim,max17201" },
	{}
	};
	MODULE_DEVICE_TABLE(of, max1720x_of_match);

	static struct i2c_driver max1720x_i2c_driver = {
	.driver = {
	.name = "max1720x",
	.of_match_table = max1720x_of_match,
	},
	.probe = max1720x_probe,
	};
	module_i2c_driver(max1720x_i2c_driver);

	MODULE_LICENSE("GPL");
	MODULE_AUTHOR("Dimitri Fedrau <dima.fedrau@gmail.com>");
	MODULE_DESCRIPTION("Maxim MAX17201/MAX17205 Fuel Gauge IC driver");