Add a driver for the Mitsumi MM8013 fuel gauge. The driver is a vastly cleaned up and improved version of the one that shipped in some obscure Lenovo downstream kernel [1], with some register definitions borrowed from ChromeOS EC platform code [2]. [1] https://github.com/adazem009/kernel_lenovo_bengal/commit/b6b346427a871715709bd22aae449b9383f3b66b [2] https://chromium.googlesource.com/chromiumos/platform/ec/+/master/driver/battery/mm8013.h Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx> --- MAINTAINERS | 5 + drivers/power/supply/Kconfig | 9 ++ drivers/power/supply/Makefile | 1 + drivers/power/supply/mm8013.c | 283 ++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 298 insertions(+) diff --git a/MAINTAINERS b/MAINTAINERS index 52d3cee7d8d4..bb79cc167b06 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -14408,6 +14408,11 @@ W: https://linuxtv.org T: git git://linuxtv.org/media_tree.git F: drivers/media/radio/radio-miropcm20* +MITSUMI MM8013 FG DRIVER +M: Konrad Dybcio <konradybcio@xxxxxxxxxx> +F: Documentation/devicetree/bindings/power/supply/mitsumi,mm8013.yaml +F: drivers/power/supply/mm8013.c + MMP SUPPORT R: Lubomir Rintel <lkundrak@xxxxx> L: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx (moderated for non-subscribers) diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig index a61bb1283e19..b355847e001a 100644 --- a/drivers/power/supply/Kconfig +++ b/drivers/power/supply/Kconfig @@ -952,4 +952,13 @@ config CHARGER_QCOM_SMB2 adds support for the SMB2 switch mode battery charger found in PMI8998 and related PMICs. +config FUEL_GAUGE_MM8013 + tristate "Mitsumi MM8013 fuel gauge driver" + depends on I2C + help + Say Y here to enable the Mitsumi MM8013 fuel gauge driver. + It enables the monitoring of many battery parameters, including + the state of charge, temperature, cycle count, actual and design + capacity, etc. + endif # POWER_SUPPLY diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile index a8a9fa6de1e9..ba2c41f060be 100644 --- a/drivers/power/supply/Makefile +++ b/drivers/power/supply/Makefile @@ -111,3 +111,4 @@ obj-$(CONFIG_BATTERY_SURFACE) += surface_battery.o obj-$(CONFIG_CHARGER_SURFACE) += surface_charger.o obj-$(CONFIG_BATTERY_UG3105) += ug3105_battery.o obj-$(CONFIG_CHARGER_QCOM_SMB2) += qcom_pmi8998_charger.o +obj-$(CONFIG_FUEL_GAUGE_MM8013) += mm8013.o diff --git a/drivers/power/supply/mm8013.c b/drivers/power/supply/mm8013.c new file mode 100644 index 000000000000..ce20c6078116 --- /dev/null +++ b/drivers/power/supply/mm8013.c @@ -0,0 +1,283 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2016-2019 The Linux Foundation. All rights reserved. + * Copyright (c) 2023, Linaro Limited + */ +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/power_supply.h> + +#define REG_BATID 0x00 /* This one is very unclear */ + #define BATID_101 0x0101 /* 107kOhm */ + #define BATID_102 0x0102 /* 10kOhm */ +#define REG_TEMPERATURE 0x06 +#define REG_VOLTAGE 0x08 +#define REG_FLAGS 0x0a + #define MM8013_FLAG_OTC BIT(15) + #define MM8013_FLAG_OTD BIT(14) + #define MM8013_FLAG_BATHI BIT(13) + #define MM8013_FLAG_FC BIT(9) + #define MM8013_FLAG_CHG BIT(8) + #define MM8013_FLAG_DSG BIT(0) +#define REG_FULL_CHARGE_CAPACITY 0x0e +#define REG_AVERAGE_CURRENT 0x14 +#define REG_AVERAGE_TIME_TO_EMPTY 0x16 +#define REG_AVERAGE_TIME_TO_FULL 0x18 +#define REG_CYCLE_COUNT 0x2a +#define REG_STATE_OF_CHARGE 0x2c +#define REG_DESIGN_CAPACITY 0x3c +/* TODO: 0x62-0x68 seem to contain 'MM8013C' in a length-prefixed, non-terminated string */ + +#define DECIKELVIN_TO_DECIDEGC(t) (t - 2731) + +struct mm8013_chip { + struct i2c_client *client; +}; + +static int mm8013_write_reg(struct i2c_client *client, u8 reg, u16 value) +{ + int ret; + + ret = i2c_smbus_write_word_data(client, reg, value); + if (ret < 0) + dev_err(&client->dev, "%s: err %d\n", __func__, ret); + + usleep_range(4000, 5000); + return ret; +} + +static int mm8013_read_reg(struct i2c_client *client, u8 reg) +{ + int ret; + + ret = i2c_smbus_read_word_data(client, reg); + if (ret < 0) + dev_err(&client->dev, "%s: err %d\n", __func__, ret); + + usleep_range(4000, 5000); + return ret; +} + +static int mm8013_checkdevice(struct mm8013_chip *chip) +{ + int battery_id, ret; + + ret = mm8013_write_reg(chip->client, REG_BATID, 0x0008); + if (ret < 0) + return ret; + + ret = mm8013_read_reg(chip->client, REG_BATID); + if (ret < 0) + return ret; + + if (ret == BATID_102) + battery_id = 2; + else if (ret == BATID_101) + battery_id = 1; + else + return -EINVAL; + + dev_dbg(&chip->client->dev, "battery_id: %d\n", battery_id); + + return 0; +} + +static enum power_supply_property mm8013_battery_props[] = { + POWER_SUPPLY_PROP_CAPACITY, + POWER_SUPPLY_PROP_CHARGE_FULL, + POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN, + POWER_SUPPLY_PROP_CURRENT_NOW, + POWER_SUPPLY_PROP_CYCLE_COUNT, + POWER_SUPPLY_PROP_HEALTH, + POWER_SUPPLY_PROP_PRESENT, + POWER_SUPPLY_PROP_STATUS, + POWER_SUPPLY_PROP_TEMP, + POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG, + POWER_SUPPLY_PROP_TIME_TO_FULL_AVG, + POWER_SUPPLY_PROP_VOLTAGE_NOW, +}; + +static int mm8013_get_property(struct power_supply *psy, + enum power_supply_property psp, + union power_supply_propval *val) +{ + struct mm8013_chip *chip = psy->drv_data; + struct i2c_client *client = chip->client; + int ret = 0; + + switch (psp) { + case POWER_SUPPLY_PROP_CAPACITY: + ret = mm8013_read_reg(client, REG_STATE_OF_CHARGE); + if (ret < 0) + return ret; + + val->intval = ret; + break; + case POWER_SUPPLY_PROP_CHARGE_FULL: + ret = mm8013_read_reg(client, REG_FULL_CHARGE_CAPACITY); + if (ret < 0) + return ret; + + val->intval = ret; + break; + case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN: + ret = mm8013_read_reg(client, REG_DESIGN_CAPACITY); + if (ret < 0) + return ret; + + val->intval = ret; + break; + case POWER_SUPPLY_PROP_CURRENT_NOW: + ret = mm8013_read_reg(client, REG_AVERAGE_CURRENT); + if (ret < 0) + return ret; + + if (ret > S16_MAX) + val->intval -= (1 << 16); + else + val->intval = ret; + + val->intval *= -1000; + break; + case POWER_SUPPLY_PROP_CYCLE_COUNT: + ret = mm8013_read_reg(client, REG_CYCLE_COUNT); + if (ret < 0) + return ret; + + val->intval = ret; + break; + case POWER_SUPPLY_PROP_HEALTH: + ret = mm8013_read_reg(client, REG_FLAGS); + if (ret < 0) + return ret; + + if (ret & MM8013_FLAG_BATHI) + val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE; + else if (ret & (MM8013_FLAG_OTD | MM8013_FLAG_OTC)) + val->intval = POWER_SUPPLY_HEALTH_OVERHEAT; + else + val->intval = POWER_SUPPLY_HEALTH_GOOD; + break; + case POWER_SUPPLY_PROP_PRESENT: + val->intval = mm8013_read_reg(client, REG_TEMPERATURE) > 0; + break; + case POWER_SUPPLY_PROP_STATUS: + ret = mm8013_read_reg(client, REG_FLAGS); + if (ret < 0) + return ret; + + if (ret & MM8013_FLAG_DSG) + val->intval = POWER_SUPPLY_STATUS_DISCHARGING; + else if (ret & MM8013_FLAG_CHG) + val->intval = POWER_SUPPLY_STATUS_CHARGING; + else if (ret & MM8013_FLAG_FC) + val->intval = POWER_SUPPLY_STATUS_FULL; + else + val->intval = POWER_SUPPLY_STATUS_UNKNOWN; + break; + case POWER_SUPPLY_PROP_TEMP: + ret = mm8013_read_reg(client, REG_TEMPERATURE); + if (ret < 0) + return ret; + + val->intval = DECIKELVIN_TO_DECIDEGC(ret); + break; + case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG: + ret = mm8013_read_reg(client, REG_AVERAGE_TIME_TO_EMPTY); + if (ret < 0) + return ret; + + /* The estimation is not yet ready */ + if (ret == U16_MAX) + return -ENODATA; + + val->intval = ret; + break; + case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG: + ret = mm8013_read_reg(client, REG_AVERAGE_TIME_TO_FULL); + if (ret < 0) + return ret; + + /* The estimation is not yet ready */ + if (ret == U16_MAX) + return -ENODATA; + + val->intval = ret; + break; + case POWER_SUPPLY_PROP_VOLTAGE_NOW: + ret = mm8013_read_reg(client, REG_VOLTAGE); + if (ret < 0) + return ret; + + val->intval = ret; + break; + default: + return -EINVAL; + } + + return 0; +} + +static const struct power_supply_desc mm8013_desc = { + .name = "mm8013", + .type = POWER_SUPPLY_TYPE_BATTERY, + .properties = mm8013_battery_props, + .num_properties = ARRAY_SIZE(mm8013_battery_props), + .get_property = mm8013_get_property, +}; + +static int mm8013_probe(struct i2c_client *client) +{ + struct power_supply_config psy_cfg = {}; + struct device *dev = &client->dev; + struct power_supply *psy; + struct mm8013_chip *chip; + int ret = 0; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA)) + return dev_err_probe(dev, -EIO, + "I2C_FUNC_SMBUS_WORD_DATA not supported\n"); + + chip = devm_kzalloc(dev, sizeof(struct mm8013_chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; + + chip->client = client; + + ret = mm8013_checkdevice(chip); + if (ret) + return dev_err_probe(dev, -ENODEV, "MM8013 not found\n"); + + psy_cfg.drv_data = chip; + psy_cfg.of_node = dev->of_node; + + psy = devm_power_supply_register(dev, &mm8013_desc, &psy_cfg); + if (IS_ERR(psy)) + return PTR_ERR(psy); + + return 0; +} + +static const struct i2c_device_id mm8013_id_table[] = { + { "mm8013", 0 }, + {}, +}; +MODULE_DEVICE_TABLE(i2c, mm8013_id_table); + +static const struct of_device_id mm8013_match_table[] = { + { .compatible = "mitsumi,mm8013" }, + { }, +}; + +static struct i2c_driver mm8013_i2c_driver = { + .probe = mm8013_probe, + .id_table = mm8013_id_table, + .driver = { + .name = "mm8013", + .of_match_table = mm8013_match_table, + }, +}; +module_i2c_driver(mm8013_i2c_driver); + +MODULE_DESCRIPTION("MM8013 fuel gauge driver"); +MODULE_LICENSE("GPL"); -- 2.42.0
