@@ -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"
@@ -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);
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.chernev@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(-)