| Message ID | 20240615203352.164234-3-dima.fedrau@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | power: supply: add support for MAX1720x standalone fuel | expand |
On 2024-06-15 22:33:50+0000, Dimitri Fedrau wrote: > The MAX17201 monitor a single cell pack. The MAX17205 monitor and balance "monitors" / "monitors and balances". > a 2S or 3S pack or monitor a multiple-series cell pack. Both device use "devices" > I2C interface. "a" I2C. > > Signed-off-by: Dimitri Fedrau <dima.fedrau@gmail.com> > --- > drivers/power/supply/Kconfig | 12 + > drivers/power/supply/Makefile | 1 + > drivers/power/supply/max1720x_battery.c | 324 ++++++++++++++++++++++++ > 3 files changed, 337 insertions(+) > create mode 100644 drivers/power/supply/max1720x_battery.c > > diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig > index 3e31375491d5..e620ae1a9c8b 100644 > --- a/drivers/power/supply/Kconfig > +++ b/drivers/power/supply/Kconfig > @@ -402,6 +402,18 @@ config BATTERY_MAX17042 > > Driver can be build as a module (max17042_battery). > > +config BATTERY_MAX1720X > +tristate "Maxim MAX17201/MAX17205 Fuel Gauge" Indentation? > + depends on I2C > + select REGMAP_I2C > + help > + MAX1720x is a family of fuel-gauge systems for lithium-ion (Li+) > + batteries in handheld and portable equipment. MAX17201 are > + configured to operate with a single lithium cell, the MAX17205 > + can operate with multiple cells. > + > + Say Y to include support for the MAX17201/MAX17205 Fuel Gauges. > + > config BATTERY_MAX1721X > tristate "MAX17211/MAX17215 standalone gas-gauge" > depends on W1 > diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile > index 58b567278034..6f02d0248826 100644 > --- a/drivers/power/supply/Makefile > +++ b/drivers/power/supply/Makefile > @@ -52,6 +52,7 @@ obj-$(CONFIG_CHARGER_DA9150) += da9150-charger.o > obj-$(CONFIG_BATTERY_DA9150) += da9150-fg.o > obj-$(CONFIG_BATTERY_MAX17040) += max17040_battery.o > obj-$(CONFIG_BATTERY_MAX17042) += max17042_battery.o > +obj-$(CONFIG_BATTERY_MAX1720X) += max1720x_battery.o > obj-$(CONFIG_BATTERY_MAX1721X) += max1721x_battery.o > obj-$(CONFIG_BATTERY_RT5033) += rt5033_battery.o > obj-$(CONFIG_CHARGER_RT5033) += rt5033_charger.o > diff --git a/drivers/power/supply/max1720x_battery.c b/drivers/power/supply/max1720x_battery.c > new file mode 100644 > index 000000000000..68d317d01c9d > --- /dev/null > +++ b/drivers/power/supply/max1720x_battery.c > @@ -0,0 +1,324 @@ > +// 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/power_supply.h> > +#include <linux/regmap.h> > + > +/* Nonvilatile registers */ Nonvolatile > +#define MAX1720_NRSENSE 0xCF /* RSense in 10^-5 Ohm */ > + > +/* 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_DESIGN_CAP 0x18 /* Design capacity */ > +#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_BATT 0xDA /* Battery voltage */ > +#define MAX172XX_ATAVCAP 0xDF > + > +static const char *max1720x_manufacturer = "Maxim Integrated"; static const char *const max1720x_manufacturer = "Maxim Integrated"; > +static const char *max17201_model = "MAX17201"; > +static const char *max17205_model = "MAX17205"; > + > +struct max1720x_device_info { > + struct power_supply *bat; > + struct power_supply_desc bat_desc; No need for bat or bat_desc in the info struct. > + struct i2c_client *ancillary; > + struct regmap *regmap; > + 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_ATAVCAP), /* volatile data */ > +}; Are MAX172XX_DEV_NAME and MAX172XX_DESIGN_CAP really volatile? > + > +static const struct regmap_range max1720x_volatile_deny[] = { > + /* volatile data 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_volatile_regs = { > + .yes_ranges = max1720x_volatile_allow, > + .n_yes_ranges = ARRAY_SIZE(max1720x_volatile_allow), > + .no_ranges = max1720x_volatile_deny, > + .n_no_ranges = ARRAY_SIZE(max1720x_volatile_deny), > +}; > + > +static const struct regmap_config max1720x_regmap_cfg = { > + .reg_bits = 8, > + .val_bits = 16, > + .val_format_endian = REGMAP_ENDIAN_LITTLE, > + .rd_table = &max1720x_volatile_regs, > + .volatile_table = &max1720x_volatile_regs, > +}; > + > +static enum power_supply_property max1720x_battery_props[] = { const. > + 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); No need for braces around (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 = 0; No need to initialize. > + 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, ®_val); > + if (ret < 0) > + return ret; > + > + val->intval = !(FIELD_GET(MAX172XX_STATUS_BAT_ABSENT, reg_val)); No need for the braces around FIELD_GET(). > + break; > + case POWER_SUPPLY_PROP_CAPACITY: > + ret = regmap_read(info->regmap, MAX172XX_REPSOC, ®_val); In case POWER_SUPPLY_PROP_PRESENT there is an early return if ret < 0. Why are the other ones different? > + val->intval = max172xx_percent_to_ps(reg_val); > + break; > + case POWER_SUPPLY_PROP_VOLTAGE_NOW: > + ret = regmap_read(info->regmap, MAX172XX_BATT, ®_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, ®_val); > + val->intval = max172xx_capacity_to_ps(reg_val); > + break; > + case POWER_SUPPLY_PROP_CHARGE_AVG: > + ret = regmap_read(info->regmap, MAX172XX_REPCAP, ®_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, ®_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, ®_val); > + val->intval = max172xx_time_to_ps(reg_val); > + break; > + case POWER_SUPPLY_PROP_TEMP: > + ret = regmap_read(info->regmap, MAX172XX_TEMP, ®_val); > + val->intval = max172xx_temperature_to_ps(reg_val); > + break; > + case POWER_SUPPLY_PROP_CURRENT_NOW: > + ret = regmap_read(info->regmap, MAX172XX_CURRENT, ®_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, ®_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, ®_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_probe_sense_resistor(struct max1720x_device_info *info) > +{ > + struct device *dev = &info->ancillary->dev; > + int ret; > + > + ret = i2c_smbus_read_word_data(info->ancillary, MAX1720_NRSENSE); > + if (ret < 0) > + return ret; Is this really backed by an smbus? AFAIK if it isn't then it's better to manually implement multi-byte readings instead of relying on the smbus emulation. > + > + info->rsense = ret; > + if (!info->rsense) { > + dev_warn(dev, "RSense not calibrated, set 10 mOhms!\n"); > + info->rsense = 1000; /* in regs in 10^-5 */ > + } > + > + return 0; > +} > + > +static int max1720x_probe(struct i2c_client *client) > +{ > + struct power_supply_config psy_cfg = {}; > + struct device *dev = &client->dev; > + struct max1720x_device_info *info; > + int ret; > + > + info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL); > + if (!info) > + return -ENOMEM; > + > + i2c_set_clientdata(client, info); > + info->bat_desc.name = "max1720x"; > + info->bat_desc.no_thermal = true; > + info->bat_desc.type = POWER_SUPPLY_TYPE_BATTERY; > + info->bat_desc.properties = max1720x_battery_props; > + info->bat_desc.num_properties = ARRAY_SIZE(max1720x_battery_props); > + info->bat_desc.get_property = max1720x_battery_get_property; > + psy_cfg.drv_data = 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"); > + > + info->ancillary = i2c_new_ancillary_device(client, "nvmem", 0xb); > + if (IS_ERR(info->ancillary)) > + return dev_err_probe(dev, PTR_ERR(info->ancillary), > + "Failed to initialize ancillary i2c device\n"); The ancillary is only used during probing. So it doesn't need to be kept around. You can pass it directly to max1720x_probe_sense_resistor(), drop it from info clean it up after usage in _probe() and get rid of max1720x_remove(). Also drop *both* calls to i2c_set_clientdata(). > + > + i2c_set_clientdata(info->ancillary, info); > + ret = max1720x_probe_sense_resistor(info); > + if (ret) { > + i2c_unregister_device(info->ancillary); > + return dev_err_probe(dev, PTR_ERR(info->bat), > + "Failed to read sense resistor value\n"); > + } > + > + info->bat = devm_power_supply_register(dev, &info->bat_desc, &psy_cfg); > + if (IS_ERR(info->bat)) { > + i2c_unregister_device(info->ancillary); > + return dev_err_probe(dev, PTR_ERR(info->bat), > + "Failed to register power supply\n"); > + } > + > + return 0; > +} > + > +static void max1720x_remove(struct i2c_client *client) > +{ > + struct max1720x_device_info *info = i2c_get_clientdata(client); > + > + i2c_unregister_device(info->ancillary); > +} > + > +static const struct of_device_id max1720x_of_match[] = { > + { .compatible = "maxim,max1720x" }, > + {}, No comma after sentinel value. > +}; > +MODULE_DEVICE_TABLE(of, max1720x_of_match); > + > +static struct i2c_driver max1720x_i2c_driver = { > + .driver = { > + .name = "max1720x", > + .of_match_table = max1720x_of_match, > + }, Alignment. > + .probe = max1720x_probe, > + .remove = max1720x_remove, > +}; > +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"); > -- > 2.39.2 >
diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig index 3e31375491d5..e620ae1a9c8b 100644 --- a/drivers/power/supply/Kconfig +++ b/drivers/power/supply/Kconfig @@ -402,6 +402,18 @@ config BATTERY_MAX17042 Driver can be build as a module (max17042_battery). +config BATTERY_MAX1720X +tristate "Maxim MAX17201/MAX17205 Fuel Gauge" + depends on I2C + select REGMAP_I2C + help + MAX1720x is a family of fuel-gauge systems for lithium-ion (Li+) + batteries in handheld and portable equipment. MAX17201 are + configured to operate with a single lithium cell, the MAX17205 + can operate with multiple cells. + + Say Y to include support for the MAX17201/MAX17205 Fuel Gauges. + config BATTERY_MAX1721X tristate "MAX17211/MAX17215 standalone gas-gauge" depends on W1 diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile index 58b567278034..6f02d0248826 100644 --- a/drivers/power/supply/Makefile +++ b/drivers/power/supply/Makefile @@ -52,6 +52,7 @@ obj-$(CONFIG_CHARGER_DA9150) += da9150-charger.o obj-$(CONFIG_BATTERY_DA9150) += da9150-fg.o obj-$(CONFIG_BATTERY_MAX17040) += max17040_battery.o obj-$(CONFIG_BATTERY_MAX17042) += max17042_battery.o +obj-$(CONFIG_BATTERY_MAX1720X) += max1720x_battery.o obj-$(CONFIG_BATTERY_MAX1721X) += max1721x_battery.o obj-$(CONFIG_BATTERY_RT5033) += rt5033_battery.o obj-$(CONFIG_CHARGER_RT5033) += rt5033_charger.o diff --git a/drivers/power/supply/max1720x_battery.c b/drivers/power/supply/max1720x_battery.c new file mode 100644 index 000000000000..68d317d01c9d --- /dev/null +++ b/drivers/power/supply/max1720x_battery.c @@ -0,0 +1,324 @@ +// 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/power_supply.h> +#include <linux/regmap.h> + +/* Nonvilatile registers */ +#define MAX1720_NRSENSE 0xCF /* RSense in 10^-5 Ohm */ + +/* 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_DESIGN_CAP 0x18 /* Design capacity */ +#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_BATT 0xDA /* Battery voltage */ +#define MAX172XX_ATAVCAP 0xDF + +static const char *max1720x_manufacturer = "Maxim Integrated"; +static const char *max17201_model = "MAX17201"; +static const char *max17205_model = "MAX17205"; + +struct max1720x_device_info { + struct power_supply *bat; + struct power_supply_desc bat_desc; + struct i2c_client *ancillary; + struct regmap *regmap; + 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_ATAVCAP), /* volatile data */ +}; + +static const struct regmap_range max1720x_volatile_deny[] = { + /* volatile data 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_volatile_regs = { + .yes_ranges = max1720x_volatile_allow, + .n_yes_ranges = ARRAY_SIZE(max1720x_volatile_allow), + .no_ranges = max1720x_volatile_deny, + .n_no_ranges = ARRAY_SIZE(max1720x_volatile_deny), +}; + +static const struct regmap_config max1720x_regmap_cfg = { + .reg_bits = 8, + .val_bits = 16, + .val_format_endian = REGMAP_ENDIAN_LITTLE, + .rd_table = &max1720x_volatile_regs, + .volatile_table = &max1720x_volatile_regs, +}; + +static 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 = 0; + 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, ®_val); + if (ret < 0) + return ret; + + val->intval = !(FIELD_GET(MAX172XX_STATUS_BAT_ABSENT, reg_val)); + break; + case POWER_SUPPLY_PROP_CAPACITY: + ret = regmap_read(info->regmap, MAX172XX_REPSOC, ®_val); + val->intval = max172xx_percent_to_ps(reg_val); + break; + case POWER_SUPPLY_PROP_VOLTAGE_NOW: + ret = regmap_read(info->regmap, MAX172XX_BATT, ®_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, ®_val); + val->intval = max172xx_capacity_to_ps(reg_val); + break; + case POWER_SUPPLY_PROP_CHARGE_AVG: + ret = regmap_read(info->regmap, MAX172XX_REPCAP, ®_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, ®_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, ®_val); + val->intval = max172xx_time_to_ps(reg_val); + break; + case POWER_SUPPLY_PROP_TEMP: + ret = regmap_read(info->regmap, MAX172XX_TEMP, ®_val); + val->intval = max172xx_temperature_to_ps(reg_val); + break; + case POWER_SUPPLY_PROP_CURRENT_NOW: + ret = regmap_read(info->regmap, MAX172XX_CURRENT, ®_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, ®_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, ®_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_probe_sense_resistor(struct max1720x_device_info *info) +{ + struct device *dev = &info->ancillary->dev; + int ret; + + ret = i2c_smbus_read_word_data(info->ancillary, MAX1720_NRSENSE); + if (ret < 0) + return ret; + + info->rsense = ret; + if (!info->rsense) { + dev_warn(dev, "RSense not calibrated, set 10 mOhms!\n"); + info->rsense = 1000; /* in regs in 10^-5 */ + } + + return 0; +} + +static int max1720x_probe(struct i2c_client *client) +{ + struct power_supply_config psy_cfg = {}; + struct device *dev = &client->dev; + struct max1720x_device_info *info; + int ret; + + info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL); + if (!info) + return -ENOMEM; + + i2c_set_clientdata(client, info); + info->bat_desc.name = "max1720x"; + info->bat_desc.no_thermal = true; + info->bat_desc.type = POWER_SUPPLY_TYPE_BATTERY; + info->bat_desc.properties = max1720x_battery_props; + info->bat_desc.num_properties = ARRAY_SIZE(max1720x_battery_props); + info->bat_desc.get_property = max1720x_battery_get_property; + psy_cfg.drv_data = 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"); + + info->ancillary = i2c_new_ancillary_device(client, "nvmem", 0xb); + if (IS_ERR(info->ancillary)) + return dev_err_probe(dev, PTR_ERR(info->ancillary), + "Failed to initialize ancillary i2c device\n"); + + i2c_set_clientdata(info->ancillary, info); + ret = max1720x_probe_sense_resistor(info); + if (ret) { + i2c_unregister_device(info->ancillary); + return dev_err_probe(dev, PTR_ERR(info->bat), + "Failed to read sense resistor value\n"); + } + + info->bat = devm_power_supply_register(dev, &info->bat_desc, &psy_cfg); + if (IS_ERR(info->bat)) { + i2c_unregister_device(info->ancillary); + return dev_err_probe(dev, PTR_ERR(info->bat), + "Failed to register power supply\n"); + } + + return 0; +} + +static void max1720x_remove(struct i2c_client *client) +{ + struct max1720x_device_info *info = i2c_get_clientdata(client); + + i2c_unregister_device(info->ancillary); +} + +static const struct of_device_id max1720x_of_match[] = { + { .compatible = "maxim,max1720x" }, + {}, +}; +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, + .remove = max1720x_remove, +}; +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");
The MAX17201 monitor a single cell pack. The MAX17205 monitor and balance a 2S or 3S pack or monitor a multiple-series cell pack. Both device use I2C interface. Signed-off-by: Dimitri Fedrau <dima.fedrau@gmail.com> --- drivers/power/supply/Kconfig | 12 + drivers/power/supply/Makefile | 1 + drivers/power/supply/max1720x_battery.c | 324 ++++++++++++++++++++++++ 3 files changed, 337 insertions(+) create mode 100644 drivers/power/supply/max1720x_battery.c