--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Battery Fuel Gauge Driver for Samsung S2MU005 PMIC.
+ *
+ * Copyright (C) 2015 Samsung Electronics
+ * Copyright (C) 2023 Yassine Oudjana <y.oudjana@protonmail.com>
+ * Copyright (C) 2025 Kaustabh Chakraborty <kauschluss@disroot.org>
+ */
+
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/mod_devicetable.h>
+#include <linux/mutex.h>
+#include <linux/power_supply.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+#include <linux/units.h>
+
+#define S2MU005_FG_REG_STATUS 0x00
+#define S2MU005_FG_REG_IRQ 0x02
+#define S2MU005_FG_REG_RVBAT 0x04
+#define S2MU005_FG_REG_RCURCC 0x06
+#define S2MU005_FG_REG_RSOC 0x08
+#define S2MU005_FG_REG_MONOUT 0x0a
+#define S2MU005_FG_REG_MONOUTSEL 0x0c
+#define S2MU005_FG_REG_RBATCAP 0x0e
+#define S2MU005_FG_REG_RZADJ 0x12
+#define S2MU005_FG_REG_RBATZ0 0x16
+#define S2MU005_FG_REG_RBATZ1 0x18
+#define S2MU005_FG_REG_IRQLVL 0x1a
+#define S2MU005_FG_REG_START 0x1e
+
+#define S2MU005_FG_MONOUTSEL_AVGCURRENT 0x26
+#define S2MU005_FG_MONOUTSEL_AVGVOLTAGE 0x27
+
+struct s2mu005_fg {
+ struct device *dev;
+ struct regmap *regmap;
+ struct power_supply *psy;
+ struct mutex monout_mutex;
+};
+
+static const struct regmap_config s2mu005_fg_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 16,
+ .val_format_endian = REGMAP_ENDIAN_LITTLE,
+};
+
+static irqreturn_t s2mu005_handle_irq(int irq, void *data)
+{
+ struct s2mu005_fg *priv = data;
+
+ msleep(100);
+ power_supply_changed(priv->psy);
+
+ return IRQ_HANDLED;
+}
+
+static int s2mu005_fg_get_voltage_now(struct s2mu005_fg *priv, int *value)
+{
+ struct regmap *regmap = priv->regmap;
+ u32 val;
+ int ret;
+
+ ret = regmap_read(regmap, S2MU005_FG_REG_RVBAT, &val);
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to read voltage register (%d)\n", ret);
+ return ret;
+ }
+
+ *value = (val * MICRO) >> 13;
+
+ return 0;
+}
+
+static int s2mu005_fg_get_voltage_avg(struct s2mu005_fg *priv, int *value)
+{
+ struct regmap *regmap = priv->regmap;
+ u32 val;
+ int ret;
+
+ mutex_lock(&priv->monout_mutex);
+
+ ret = regmap_write(regmap, S2MU005_FG_REG_MONOUTSEL,
+ S2MU005_FG_MONOUTSEL_AVGVOLTAGE);
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to enable average voltage monitoring (%d)\n",
+ ret);
+ goto unlock;
+ }
+
+ ret = regmap_read(regmap, S2MU005_FG_REG_MONOUT, &val);
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to read current register (%d)\n", ret);
+ goto unlock;
+ }
+
+ *value = (val * MICRO) >> 12;
+
+unlock:
+ mutex_unlock(&priv->monout_mutex);
+
+ return ret;
+}
+static int s2mu005_fg_get_current_now(struct s2mu005_fg *priv, int *value)
+{
+ struct regmap *regmap = priv->regmap;
+ u32 val;
+ int ret;
+
+ ret = regmap_read(regmap, S2MU005_FG_REG_RCURCC, &val);
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to read current register (%d)\n", ret);
+ return ret;
+ }
+
+ *value = -((s16)val * MICRO) >> 12;
+
+ return 0;
+}
+
+static int s2mu005_fg_get_current_avg(struct s2mu005_fg *priv, int *value)
+{
+ struct regmap *regmap = priv->regmap;
+ u32 val;
+ int ret;
+
+ mutex_lock(&priv->monout_mutex);
+
+ ret = regmap_write(regmap, S2MU005_FG_REG_MONOUTSEL,
+ S2MU005_FG_MONOUTSEL_AVGCURRENT);
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to enable average current monitoring (%d)\n",
+ ret);
+ goto unlock;
+ }
+
+ ret = regmap_read(regmap, S2MU005_FG_REG_MONOUT, &val);
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to read current register (%d)\n", ret);
+ goto unlock;
+ }
+
+ *value = -((s16)val * MICRO) >> 12;
+
+unlock:
+ mutex_unlock(&priv->monout_mutex);
+
+ return ret;
+}
+
+static int s2mu005_fg_get_capacity(struct s2mu005_fg *priv, int *value)
+{
+ struct regmap *regmap = priv->regmap;
+ u32 val;
+ int ret;
+
+ ret = regmap_read(regmap, S2MU005_FG_REG_RSOC, &val);
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to read capacity register (%d)\n", ret);
+ return ret;
+ }
+
+ *value = (val * CENTI) >> 14;
+
+ return 0;
+}
+
+static int s2mu005_fg_get_status(struct s2mu005_fg *priv, int *value)
+{
+ int current_now, current_avg, capacity;
+ int ret;
+
+ ret = s2mu005_fg_get_current_now(priv, ¤t_now);
+ if (ret < 0)
+ return ret;
+
+ ret = s2mu005_fg_get_current_avg(priv, ¤t_avg);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * Verify both current values reported to reduce inaccuracies due to
+ * internal hysteresis.
+ */
+ if (current_now < 0 && current_avg < 0) {
+ *value = POWER_SUPPLY_STATUS_DISCHARGING;
+ } else if (current_now == 0) {
+ *value = POWER_SUPPLY_STATUS_NOT_CHARGING;
+ } else {
+ *value = POWER_SUPPLY_STATUS_CHARGING;
+
+ ret = s2mu005_fg_get_capacity(priv, &capacity);
+ if (!ret && capacity > 98)
+ *value = POWER_SUPPLY_STATUS_FULL;
+ return ret;
+ }
+
+ return 0;
+}
+
+static const enum power_supply_property s2mu005_fg_properties[] = {
+ POWER_SUPPLY_PROP_VOLTAGE_NOW,
+ POWER_SUPPLY_PROP_VOLTAGE_AVG,
+ POWER_SUPPLY_PROP_CURRENT_NOW,
+ POWER_SUPPLY_PROP_CURRENT_AVG,
+ POWER_SUPPLY_PROP_CAPACITY,
+ POWER_SUPPLY_PROP_STATUS,
+};
+
+static int s2mu005_fg_get_property(struct power_supply *psy,
+ enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ struct s2mu005_fg *priv = power_supply_get_drvdata(psy);
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+ return s2mu005_fg_get_voltage_now(priv, &val->intval);
+ case POWER_SUPPLY_PROP_VOLTAGE_AVG:
+ return s2mu005_fg_get_voltage_avg(priv, &val->intval);
+ case POWER_SUPPLY_PROP_CURRENT_NOW:
+ return s2mu005_fg_get_current_now(priv, &val->intval);
+ case POWER_SUPPLY_PROP_CURRENT_AVG:
+ return s2mu005_fg_get_current_avg(priv, &val->intval);
+ case POWER_SUPPLY_PROP_CAPACITY:
+ return s2mu005_fg_get_capacity(priv, &val->intval);
+ case POWER_SUPPLY_PROP_STATUS:
+ return s2mu005_fg_get_status(priv, &val->intval);
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct power_supply_desc s2mu005_fg_desc = {
+ .name = "s2mu005-fuel-gauge",
+ .type = POWER_SUPPLY_TYPE_BATTERY,
+ .properties = s2mu005_fg_properties,
+ .num_properties = ARRAY_SIZE(s2mu005_fg_properties),
+ .get_property = s2mu005_fg_get_property,
+};
+
+static int s2mu005_fg_i2c_probe(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ struct s2mu005_fg *priv;
+ struct power_supply_config psy_cfg = {};
+ const struct power_supply_desc *psy_desc;
+ int ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ dev_set_drvdata(dev, priv);
+ priv->dev = dev;
+
+ priv->regmap = devm_regmap_init_i2c(client, &s2mu005_fg_regmap_config);
+ if (IS_ERR(priv->regmap))
+ return dev_err_probe(dev, PTR_ERR(priv->regmap),
+ "failed to initialize regmap\n");
+
+ ret = devm_mutex_init(dev, &priv->monout_mutex);
+ if (ret)
+ dev_err_probe(dev, ret, "failed to initialize MONOUT mutex\n");
+
+ psy_desc = device_get_match_data(dev);
+
+ psy_cfg.drv_data = priv;
+ psy_cfg.fwnode = dev_fwnode(dev);
+ priv->psy = devm_power_supply_register(priv->dev, psy_desc, &psy_cfg);
+ if (IS_ERR(priv->psy))
+ return dev_err_probe(dev, PTR_ERR(priv->psy),
+ "failed to register power supply subsystem\n");
+
+ ret = devm_request_threaded_irq(priv->dev, client->irq, NULL,
+ s2mu005_handle_irq, IRQF_ONESHOT,
+ psy_desc->name, priv);
+ if (ret)
+ dev_err_probe(dev, ret, "failed to request IRQ\n");
+
+ return 0;
+}
+
+static const struct of_device_id s2mu005_fg_of_match_table[] = {
+ {
+ .compatible = "samsung,s2mu005-fuel-gauge",
+ .data = &s2mu005_fg_desc,
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(of, s2mu005_fg_of_match_table);
+
+static struct i2c_driver s2mu005_fg_i2c_driver = {
+ .probe = s2mu005_fg_i2c_probe,
+ .driver = {
+ .name = "s2mu005-fuel-gauge",
+ .of_match_table = s2mu005_fg_of_match_table,
+ },
+};
+module_i2c_driver(s2mu005_fg_i2c_driver);
+
+MODULE_DESCRIPTION("Samsung S2MU005 PMIC Battery Fuel Gauge Driver");
+MODULE_AUTHOR("Yassine Oudjana <y.oudjana@protonmail.com>");
+MODULE_AUTHOR("Kaustabh Chakraborty <kauschluss@disroot.org>");
+MODULE_LICENSE("GPL");
projects / thirdparty / kernel / linux.git / commitdiff
