The max17040 fuel gauge is part of a family of 8 chips that have very similar mode of operations and registers.
This change adds: - compatible strings for all supported devices and handles the minor differences between them; - handling for devices reporting double capacity via maxim,double-soc; - handling for setting rcomp, a compensation value for more accurate reading, affected by battery chemistry and operating temps; - suppot for SOC alerts (capacity changes by +/- 1%), to prevent polling every second; - redo i2c read/writes via regmap The datasheets of the supported devices are linked [0] [1] [2] [3]. [0] https://datasheets.maximintegrated.com/en/ds/MAX17040-MAX17041.pdf [1] https://datasheets.maximintegrated.com/en/ds/MAX17043-MAX17044.pdf [2] https://datasheets.maximintegrated.com/en/ds/MAX17048-MAX17049.pdf [3] https://datasheets.maximintegrated.com/en/ds/MAX17058-MAX17059.pdf Signed-off-by: Iskren Chernev <iskren.cher...@gmail.com> --- v1: https://lkml.org/lkml/2020/6/8/683 changes in v2: - make max17040_family static - fix rcomp len check - implement maxim,skip-reset - reword Kconfig text drivers/power/supply/Kconfig | 11 +- drivers/power/supply/max17040_battery.c | 466 +++++++++++++++++------- 2 files changed, 338 insertions(+), 139 deletions(-) diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig index 44d3c8512fb8d..69e9eaa100d9f 100644 --- a/drivers/power/supply/Kconfig +++ b/drivers/power/supply/Kconfig @@ -368,9 +368,14 @@ config BATTERY_MAX17040 tristate "Maxim MAX17040 Fuel Gauge" depends on I2C help - MAX17040 is fuel-gauge systems for lithium-ion (Li+) batteries - in handheld and portable equipment. The MAX17040 is configured - to operate with a single lithium cell + Maxim models with ModelGauge are fuel-gauge systems for lithium-ion + (Li+) batteries in handheld and portable equipment, including + max17040, max17041, max17043, max17044, max17048, max17049, max17058, + max17059. It is also included in some batteries like max77836. + + Driver supports reporting SOC (State of Charge, i.e capacity), + voltage and configurable low-SOC wakeup interrupt. For certain models + a SOC change interrupt is also supported. config BATTERY_MAX17042 tristate "Maxim MAX17042/17047/17050/8997/8966 Fuel Gauge" diff --git a/drivers/power/supply/max17040_battery.c b/drivers/power/supply/max17040_battery.c index 48aa44665e2f1..1244982cacacb 100644 --- a/drivers/power/supply/max17040_battery.c +++ b/drivers/power/supply/max17040_battery.c @@ -15,193 +15,342 @@ #include <linux/delay.h> #include <linux/interrupt.h> #include <linux/power_supply.h> +#include <linux/of_device.h> #include <linux/max17040_battery.h> +#include <linux/regmap.h> #include <linux/slab.h> #define MAX17040_VCELL 0x02 #define MAX17040_SOC 0x04 #define MAX17040_MODE 0x06 #define MAX17040_VER 0x08 -#define MAX17040_RCOMP 0x0C +#define MAX17040_CONFIG 0x0C +#define MAX17040_STATUS 0x1A #define MAX17040_CMD 0xFE #define MAX17040_DELAY 1000 #define MAX17040_BATTERY_FULL 95 +#define MAX17040_RCOMP_DEFAULT 0x9700 -#define MAX17040_ATHD_MASK 0xFFC0 +#define MAX17040_ATHD_MASK 0x3f +#define MAX17040_ALSC_MASK 0x40 #define MAX17040_ATHD_DEFAULT_POWER_UP 4 +#define MAX17040_STATUS_HD_MASK 0x1000 +#define MAX17040_STATUS_SC_MASK 0x2000 +#define MAX17040_CFG_RCOMP_MASK 0xff00 + +enum chip_id { + ID_MAX17040, + ID_MAX17041, + ID_MAX17043, + ID_MAX17044, + ID_MAX17048, + ID_MAX17049, + ID_MAX17058, + ID_MAX17059, +}; + +/* values that differ by chip_id */ +struct chip_data { + u16 reset_val; + u16 vcell_shift; + u16 vcell_mul; + u16 vcell_div; + u8 rcomp_bytes; + u8 has_low_soc_alert; + u8 has_soc_alert; +}; + +static struct chip_data max17040_family[] = { + [ID_MAX17040] = { + .reset_val = 0x0054, + .vcell_shift = 4, + .vcell_mul = 1250, + .vcell_div = 1, + .rcomp_bytes = 2, + .has_low_soc_alert = 0, + .has_soc_alert = 0, + }, + [ID_MAX17041] = { + .reset_val = 0x0054, + .vcell_shift = 4, + .vcell_mul = 2500, + .vcell_div = 1, + .rcomp_bytes = 2, + .has_low_soc_alert = 0, + .has_soc_alert = 0, + }, + [ID_MAX17043] = { + .reset_val = 0x0054, + .vcell_shift = 4, + .vcell_mul = 1250, + .vcell_div = 1, + .rcomp_bytes = 1, + .has_low_soc_alert = 1, + .has_soc_alert = 0, + }, + [ID_MAX17044] = { + .reset_val = 0x0054, + .vcell_shift = 4, + .vcell_mul = 2500, + .vcell_div = 1, + .rcomp_bytes = 1, + .has_low_soc_alert = 1, + .has_soc_alert = 0, + }, + [ID_MAX17048] = { + .reset_val = 0x5400, + .vcell_shift = 0, + .vcell_mul = 625, + .vcell_div = 8, + .rcomp_bytes = 1, + .has_low_soc_alert = 1, + .has_soc_alert = 1, + }, + [ID_MAX17049] = { + .reset_val = 0x5400, + .vcell_shift = 0, + .vcell_mul = 625, + .vcell_div = 4, + .rcomp_bytes = 1, + .has_low_soc_alert = 1, + .has_soc_alert = 1, + }, + [ID_MAX17058] = { + .reset_val = 0x5400, + .vcell_shift = 0, + .vcell_mul = 625, + .vcell_div = 8, + .rcomp_bytes = 1, + .has_low_soc_alert = 1, + .has_soc_alert = 0, + }, + [ID_MAX17059] = { + .reset_val = 0x5400, + .vcell_shift = 0, + .vcell_mul = 625, + .vcell_div = 4, + .rcomp_bytes = 1, + .has_low_soc_alert = 1, + .has_soc_alert = 0, + }, +}; struct max17040_chip { struct i2c_client *client; + struct regmap *regmap; struct delayed_work work; struct power_supply *battery; struct max17040_platform_data *pdata; + struct chip_data data; - /* State Of Connect */ - int online; - /* battery voltage */ - int vcell; /* battery capacity */ int soc; /* State Of Charge */ int status; + /* Low alert threshold from 32% to 1% of the State of Charge */ u32 low_soc_alert; + /* some devices return twice the capacity */ + bool quirk_double_soc; + /* resetting causes some devices to show inaccurate reading */ + bool quirk_skip_reset; + /* higher 8 bits for 17043+, 16 bits for 17040,41 */ + u16 rcomp; }; -static int max17040_get_property(struct power_supply *psy, - enum power_supply_property psp, - union power_supply_propval *val) +static int max17040_reset(struct max17040_chip *chip) { - struct max17040_chip *chip = power_supply_get_drvdata(psy); - - switch (psp) { - case POWER_SUPPLY_PROP_STATUS: - val->intval = chip->status; - break; - case POWER_SUPPLY_PROP_ONLINE: - val->intval = chip->online; - break; - case POWER_SUPPLY_PROP_VOLTAGE_NOW: - val->intval = chip->vcell; - break; - case POWER_SUPPLY_PROP_CAPACITY: - val->intval = chip->soc; - break; - default: - return -EINVAL; - } - return 0; + return regmap_write(chip->regmap, MAX17040_CMD, chip->data.reset_val); } -static int max17040_write_reg(struct i2c_client *client, int reg, u16 value) +static int max17040_set_low_soc_alert(struct max17040_chip *chip, u32 level) { - int ret; - - ret = i2c_smbus_write_word_swapped(client, reg, value); - - if (ret < 0) - dev_err(&client->dev, "%s: err %d\n", __func__, ret); + level = 32 - level; + return regmap_update_bits(chip->regmap, MAX17040_CONFIG, + MAX17040_ATHD_MASK, level); +} - return ret; +static int max17040_set_soc_alert(struct max17040_chip *chip, bool enable) +{ + return regmap_update_bits(chip->regmap, MAX17040_CONFIG, + MAX17040_ALSC_MASK, enable ? MAX17040_ALSC_MASK : 0); } -static int max17040_read_reg(struct i2c_client *client, int reg) +/* Returns true if alert cause was SOC change, not low SOC */ +static bool max17040_handle_soc_alert(struct max17040_chip *chip) { - int ret; + bool ret = true; + u32 data; - ret = i2c_smbus_read_word_swapped(client, reg); + regmap_read(chip->regmap, MAX17040_STATUS, &data); - if (ret < 0) - dev_err(&client->dev, "%s: err %d\n", __func__, ret); + if (data & MAX17040_STATUS_HD_MASK) { + // this alert was caused by low soc + ret = false; + } + if (data & MAX17040_STATUS_SC_MASK) { + // soc change bit -- deassert to mark as handled + regmap_write(chip->regmap, MAX17040_STATUS, + data & ~MAX17040_STATUS_SC_MASK); + } return ret; } -static void max17040_reset(struct i2c_client *client) +static int max17040_set_rcomp(struct max17040_chip *chip, u16 rcomp) { - max17040_write_reg(client, MAX17040_CMD, 0x0054); + u16 mask = chip->data.rcomp_bytes == 2 ? + 0xffff : MAX17040_CFG_RCOMP_MASK; + + return regmap_update_bits(chip->regmap, MAX17040_CONFIG, mask, rcomp); } -static int max17040_set_low_soc_alert(struct i2c_client *client, u32 level) +static int max17040_raw_vcell_to_uvolts(struct max17040_chip *chip, u16 vcell) { - int ret; - u16 data; - - level = 32 - level; - data = max17040_read_reg(client, MAX17040_RCOMP); - /* clear the alrt bit and set LSb 5 bits */ - data &= MAX17040_ATHD_MASK; - data |= level; - ret = max17040_write_reg(client, MAX17040_RCOMP, data); + struct chip_data *d = &chip->data; - return ret; + return (vcell >> d->vcell_shift) * d->vcell_mul / d->vcell_div; } -static void max17040_get_vcell(struct i2c_client *client) +static int max17040_get_vcell(struct max17040_chip *chip) { - struct max17040_chip *chip = i2c_get_clientdata(client); - u16 vcell; + u32 vcell; - vcell = max17040_read_reg(client, MAX17040_VCELL); + regmap_read(chip->regmap, MAX17040_VCELL, &vcell); - chip->vcell = (vcell >> 4) * 1250; + return max17040_raw_vcell_to_uvolts(chip, vcell); } -static void max17040_get_soc(struct i2c_client *client) +static int max17040_raw_soc_to_percent(struct max17040_chip *chip, u16 soc) { - struct max17040_chip *chip = i2c_get_clientdata(client); - u16 soc; + int shift = 8; - soc = max17040_read_reg(client, MAX17040_SOC); + if (chip->quirk_double_soc) + shift += 1; - chip->soc = (soc >> 8); + return soc >> shift; } -static void max17040_get_version(struct i2c_client *client) +static int max17040_get_soc(struct max17040_chip *chip) { - u16 version; + u32 soc; - version = max17040_read_reg(client, MAX17040_VER); + regmap_read(chip->regmap, MAX17040_SOC, &soc); - dev_info(&client->dev, "MAX17040 Fuel-Gauge Ver 0x%x\n", version); + return max17040_raw_soc_to_percent(chip, soc); } -static void max17040_get_online(struct i2c_client *client) +static void max17040_get_version(struct max17040_chip *chip) { - struct max17040_chip *chip = i2c_get_clientdata(client); + u32 version; - if (chip->pdata && chip->pdata->battery_online) - chip->online = chip->pdata->battery_online(); - else - chip->online = 1; + regmap_read(chip->regmap, MAX17040_VER, &version); + + dev_dbg(&chip->client->dev, "MAX17040 Fuel-Gauge Ver 0x%x\n", version); } -static void max17040_get_status(struct i2c_client *client) +static int max17040_get_online(struct max17040_chip *chip) { - struct max17040_chip *chip = i2c_get_clientdata(client); + return chip->pdata && chip->pdata->battery_online ? + chip->pdata->battery_online() : 1; +} +static int max17040_get_status(struct max17040_chip *chip) +{ if (!chip->pdata || !chip->pdata->charger_online || !chip->pdata->charger_enable) { - chip->status = POWER_SUPPLY_STATUS_UNKNOWN; - return; + return POWER_SUPPLY_STATUS_UNKNOWN; } + if (max17040_get_soc(chip) > MAX17040_BATTERY_FULL) + return POWER_SUPPLY_STATUS_FULL; + if (chip->pdata->charger_online()) { if (chip->pdata->charger_enable()) - chip->status = POWER_SUPPLY_STATUS_CHARGING; + return POWER_SUPPLY_STATUS_CHARGING; else - chip->status = POWER_SUPPLY_STATUS_NOT_CHARGING; + return POWER_SUPPLY_STATUS_NOT_CHARGING; } else { - chip->status = POWER_SUPPLY_STATUS_DISCHARGING; + return POWER_SUPPLY_STATUS_DISCHARGING; } +} + +static int max17040_get_property(struct power_supply *psy, + enum power_supply_property psp, + union power_supply_propval *val) +{ + struct max17040_chip *chip = power_supply_get_drvdata(psy); - if (chip->soc > MAX17040_BATTERY_FULL) - chip->status = POWER_SUPPLY_STATUS_FULL; + switch (psp) { + case POWER_SUPPLY_PROP_STATUS: + val->intval = max17040_get_status(chip); + break; + case POWER_SUPPLY_PROP_ONLINE: + val->intval = max17040_get_online(chip); + break; + case POWER_SUPPLY_PROP_VOLTAGE_NOW: + val->intval = max17040_get_vcell(chip); + break; + case POWER_SUPPLY_PROP_CAPACITY: + val->intval = max17040_get_soc(chip); + break; + default: + return -EINVAL; + } + return 0; } + static int max17040_get_of_data(struct max17040_chip *chip) { struct device *dev = &chip->client->dev; + struct chip_data *data = &max17040_family[ + (enum chip_id) of_device_get_match_data(dev)]; + int rcomp_len; + u8 rcomp[2]; chip->low_soc_alert = MAX17040_ATHD_DEFAULT_POWER_UP; device_property_read_u32(dev, "maxim,alert-low-soc-level", &chip->low_soc_alert); - if (chip->low_soc_alert <= 0 || chip->low_soc_alert >= 33) + if (chip->low_soc_alert <= 0 || chip->low_soc_alert >= 33) { + dev_err(dev, "maxim,alert-low-soc-level out of bounds\n"); return -EINVAL; + } + + chip->quirk_double_soc = device_property_read_bool(dev, + "maxim,double-soc"); + chip->quirk_skip_reset = device_property_read_bool(dev, + "maxim,skip-reset"); + rcomp_len = device_property_count_u8(dev, "maxim,rcomp"); + chip->rcomp = MAX17040_RCOMP_DEFAULT; + if (rcomp_len == data->rcomp_bytes) { + device_property_read_u8_array(dev, "maxim,rcomp", + rcomp, rcomp_len); + chip->rcomp = rcomp_len == 2 ? + rcomp[0] << 8 | rcomp[1] : + rcomp[0] << 8; + } else if (rcomp_len > 0) { + dev_err(dev, "maxim,rcomp has incorrect length\n"); + return -EINVAL; + } return 0; } -static void max17040_check_changes(struct i2c_client *client) +static void max17040_check_changes(struct max17040_chip *chip) { - max17040_get_vcell(client); - max17040_get_soc(client); - max17040_get_online(client); - max17040_get_status(client); + chip->soc = max17040_get_soc(chip); + chip->status = max17040_get_status(chip); +} + +static void max17040_queue_work(struct max17040_chip *chip) +{ + queue_delayed_work(system_power_efficient_wq, &chip->work, + MAX17040_DELAY); } static void max17040_work(struct work_struct *work) @@ -214,35 +363,42 @@ static void max17040_work(struct work_struct *work) /* store SOC and status to check changes */ last_soc = chip->soc; last_status = chip->status; - max17040_check_changes(chip->client); + max17040_check_changes(chip); /* check changes and send uevent */ if (last_soc != chip->soc || last_status != chip->status) power_supply_changed(chip->battery); - queue_delayed_work(system_power_efficient_wq, &chip->work, - MAX17040_DELAY); + max17040_queue_work(chip); +} + +static void max17040_stop_work(void *data) +{ + struct max17040_chip *chip = data; + + cancel_delayed_work_sync(&chip->work); } static irqreturn_t max17040_thread_handler(int id, void *dev) { struct max17040_chip *chip = dev; - struct i2c_client *client = chip->client; - dev_warn(&client->dev, "IRQ: Alert battery low level"); + if (!(chip->data.has_soc_alert && max17040_handle_soc_alert(chip))) + dev_warn(&chip->client->dev, "IRQ: Alert battery low level\n"); + /* read registers */ - max17040_check_changes(chip->client); + max17040_check_changes(chip); /* send uevent */ power_supply_changed(chip->battery); - /* reset alert bit */ - max17040_set_low_soc_alert(client, chip->low_soc_alert); + /* reset low soc alert bit */ + max17040_set_low_soc_alert(chip, chip->low_soc_alert); return IRQ_HANDLED; } -static int max17040_enable_alert_irq(struct max17040_chip *chip) +static int max17040_setup_irq(struct max17040_chip *chip) { struct i2c_client *client = chip->client; unsigned int flags; @@ -256,6 +412,13 @@ static int max17040_enable_alert_irq(struct max17040_chip *chip) return ret; } +static const struct regmap_config max17040_regmap = { + .reg_bits = 8, + .reg_stride = 2, + .val_bits = 16, + .val_format_endian = REGMAP_ENDIAN_BIG, +}; + static enum power_supply_property max17040_battery_props[] = { POWER_SUPPLY_PROP_STATUS, POWER_SUPPLY_PROP_ONLINE, @@ -277,6 +440,8 @@ static int max17040_probe(struct i2c_client *client, struct i2c_adapter *adapter = client->adapter; struct power_supply_config psy_cfg = {}; struct max17040_chip *chip; + enum chip_id chip_id; + bool enable_irq = false; int ret; if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE)) @@ -287,38 +452,63 @@ static int max17040_probe(struct i2c_client *client, return -ENOMEM; chip->client = client; + chip->regmap = devm_regmap_init_i2c(client, &max17040_regmap); chip->pdata = client->dev.platform_data; - ret = max17040_get_of_data(chip); - if (ret) { - dev_err(&client->dev, - "failed: low SOC alert OF data out of bounds\n"); - return ret; + chip_id = (enum chip_id) id->driver_data; + if (client->dev.of_node) { + ret = max17040_get_of_data(chip); + if (ret) + return ret; + chip_id = (enum chip_id) of_device_get_match_data(&client->dev); } + chip->data = max17040_family[chip_id]; i2c_set_clientdata(client, chip); psy_cfg.drv_data = chip; - chip->battery = power_supply_register(&client->dev, - &max17040_battery_desc, &psy_cfg); + chip->battery = devm_power_supply_register(&client->dev, + &max17040_battery_desc, &psy_cfg); if (IS_ERR(chip->battery)) { dev_err(&client->dev, "failed: power supply register\n"); return PTR_ERR(chip->battery); } - max17040_reset(client); - max17040_get_version(client); + if (!chip->quirk_skip_reset) { + max17040_reset(chip); + } + max17040_get_version(chip); + max17040_set_rcomp(chip, chip->rcomp); /* check interrupt */ - if (client->irq && of_device_is_compatible(client->dev.of_node, - "maxim,max77836-battery")) { - ret = max17040_set_low_soc_alert(client, chip->low_soc_alert); + if (client->irq && chip->data.has_low_soc_alert) { + ret = max17040_set_low_soc_alert(chip, chip->low_soc_alert); if (ret) { dev_err(&client->dev, "Failed to set low SOC alert: err %d\n", ret); return ret; } + enable_irq = true; + } + + if (client->irq && chip->data.has_soc_alert) { + ret = max17040_set_soc_alert(chip, 1); + if (ret) { + dev_err(&client->dev, + "Failed to set SOC alert: err %d\n", ret); + return ret; + } + enable_irq = true; + } else { + /* soc alerts negate the need for polling */ + INIT_DEFERRABLE_WORK(&chip->work, max17040_work); + ret = devm_add_action(&client->dev, max17040_stop_work, chip); + if (ret) + return ret; + max17040_queue_work(chip); + } - ret = max17040_enable_alert_irq(chip); + if (enable_irq) { + ret = max17040_setup_irq(chip); if (ret) { client->irq = 0; dev_warn(&client->dev, @@ -326,19 +516,6 @@ static int max17040_probe(struct i2c_client *client, } } - INIT_DEFERRABLE_WORK(&chip->work, max17040_work); - queue_delayed_work(system_power_efficient_wq, &chip->work, - MAX17040_DELAY); - - return 0; -} - -static int max17040_remove(struct i2c_client *client) -{ - struct max17040_chip *chip = i2c_get_clientdata(client); - - power_supply_unregister(chip->battery); - cancel_delayed_work(&chip->work); return 0; } @@ -349,10 +526,13 @@ static int max17040_suspend(struct device *dev) struct i2c_client *client = to_i2c_client(dev); struct max17040_chip *chip = i2c_get_clientdata(client); - cancel_delayed_work(&chip->work); - if (client->irq && device_may_wakeup(dev)) enable_irq_wake(client->irq); + if (client->irq && chip->data.has_soc_alert) + // disable soc alert to prevent wakeup + max17040_set_soc_alert(chip, 0); + else + cancel_delayed_work(&chip->work); return 0; } @@ -362,11 +542,12 @@ static int max17040_resume(struct device *dev) struct i2c_client *client = to_i2c_client(dev); struct max17040_chip *chip = i2c_get_clientdata(client); - queue_delayed_work(system_power_efficient_wq, &chip->work, - MAX17040_DELAY); - if (client->irq && device_may_wakeup(dev)) disable_irq_wake(client->irq); + if (client->irq && chip->data.has_soc_alert) + max17040_set_soc_alert(chip, 1); + else + max17040_queue_work(chip); return 0; } @@ -381,16 +562,30 @@ static SIMPLE_DEV_PM_OPS(max17040_pm_ops, max17040_suspend, max17040_resume); #endif /* CONFIG_PM_SLEEP */ static const struct i2c_device_id max17040_id[] = { - { "max17040" }, - { "max77836-battery" }, - { } + { "max17040", ID_MAX17040 }, + { "max17041", ID_MAX17041 }, + { "max17043", ID_MAX17043 }, + { "max77836-battery", ID_MAX17043 }, + { "max17044", ID_MAX17044 }, + { "max17048", ID_MAX17048 }, + { "max17049", ID_MAX17049 }, + { "max17058", ID_MAX17058 }, + { "max17059", ID_MAX17059 }, + { /* sentinel */ } }; MODULE_DEVICE_TABLE(i2c, max17040_id); static const struct of_device_id max17040_of_match[] = { - { .compatible = "maxim,max17040" }, - { .compatible = "maxim,max77836-battery" }, - { }, + { .compatible = "maxim,max17040", .data = (void *) ID_MAX17040 }, + { .compatible = "maxim,max17041", .data = (void *) ID_MAX17041 }, + { .compatible = "maxim,max17043", .data = (void *) ID_MAX17043 }, + { .compatible = "maxim,max77836-battery", .data = (void *) ID_MAX17043 }, + { .compatible = "maxim,max17044", .data = (void *) ID_MAX17044 }, + { .compatible = "maxim,max17048", .data = (void *) ID_MAX17048 }, + { .compatible = "maxim,max17049", .data = (void *) ID_MAX17049 }, + { .compatible = "maxim,max17058", .data = (void *) ID_MAX17058 }, + { .compatible = "maxim,max17059", .data = (void *) ID_MAX17059 }, + { /* sentinel */ }, }; MODULE_DEVICE_TABLE(of, max17040_of_match); @@ -401,7 +596,6 @@ static struct i2c_driver max17040_i2c_driver = { .pm = MAX17040_PM_OPS, }, .probe = max17040_probe, - .remove = max17040_remove, .id_table = max17040_id, }; module_i2c_driver(max17040_i2c_driver); -- 2.27.0
