[PATCH v3 4/4] power: supply: Add Spreadtrum SC27XX fuel gauge unit driver
From: Baolin Wang
Date: Thu Sep 27 2018 - 03:28:10 EST
This patch adds the Spreadtrum SC27XX serial PMICs fuel gauge support,
which is used to calculate the battery capacity.
Original-by: Yuanjiang Yu <yuanjiang.yu@xxxxxxxxxx>
Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
Acked-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
---
Changes from v2:
- Use core helper functions to look up OCV capacity table.
- Use device_property_read_u32() instead of of_property_read_u32().
- Add acked tag from Linus.
Changes from v1:
- Use battery standard properties to get internal resistance and ocv table.
- Change devm_gpiod_get_optional() to devm_gpiod_get().
- Add power_supply_changed() when detecting battery present change.
- Return micro volts for sc27xx_fgu_get_vbat_ocv().
---
drivers/power/supply/Kconfig | 7 +
drivers/power/supply/Makefile | 1 +
drivers/power/supply/sc27xx_fuel_gauge.c | 661 ++++++++++++++++++++++++++++++
3 files changed, 669 insertions(+)
create mode 100644 drivers/power/supply/sc27xx_fuel_gauge.c
diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
index f27cf07..917f4b7 100644
--- a/drivers/power/supply/Kconfig
+++ b/drivers/power/supply/Kconfig
@@ -652,4 +652,11 @@ config CHARGER_SC2731
Say Y here to enable support for battery charging with SC2731
PMIC chips.
+config FUEL_GAUGE_SC27XX
+ tristate "Spreadtrum SC27XX fuel gauge driver"
+ depends on MFD_SC27XX_PMIC || COMPILE_TEST
+ help
+ Say Y here to enable support for fuel gauge with SC27XX
+ PMIC chips.
+
endif # POWER_SUPPLY
diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
index 767105b..b731c2a 100644
--- a/drivers/power/supply/Makefile
+++ b/drivers/power/supply/Makefile
@@ -86,3 +86,4 @@ obj-$(CONFIG_AXP288_FUEL_GAUGE) += axp288_fuel_gauge.o
obj-$(CONFIG_AXP288_CHARGER) += axp288_charger.o
obj-$(CONFIG_CHARGER_CROS_USBPD) += cros_usbpd-charger.o
obj-$(CONFIG_CHARGER_SC2731) += sc2731_charger.o
+obj-$(CONFIG_FUEL_GAUGE_SC27XX) += sc27xx_fuel_gauge.o
diff --git a/drivers/power/supply/sc27xx_fuel_gauge.c b/drivers/power/supply/sc27xx_fuel_gauge.c
new file mode 100644
index 0000000..1c0b856
--- /dev/null
+++ b/drivers/power/supply/sc27xx_fuel_gauge.c
@@ -0,0 +1,661 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Spreadtrum Communications Inc.
+
+#include <linux/gpio/consumer.h>
+#include <linux/iio/consumer.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/regmap.h>
+
+/* PMIC global control registers definition */
+#define SC27XX_MODULE_EN0 0xc08
+#define SC27XX_CLK_EN0 0xc18
+#define SC27XX_FGU_EN BIT(7)
+#define SC27XX_FGU_RTC_EN BIT(6)
+
+/* FGU registers definition */
+#define SC27XX_FGU_START 0x0
+#define SC27XX_FGU_CONFIG 0x4
+#define SC27XX_FGU_ADC_CONFIG 0x8
+#define SC27XX_FGU_STATUS 0xc
+#define SC27XX_FGU_INT_EN 0x10
+#define SC27XX_FGU_INT_CLR 0x14
+#define SC27XX_FGU_INT_STS 0x1c
+#define SC27XX_FGU_VOLTAGE 0x20
+#define SC27XX_FGU_OCV 0x24
+#define SC27XX_FGU_POCV 0x28
+#define SC27XX_FGU_CURRENT 0x2c
+#define SC27XX_FGU_CLBCNT_SETH 0x50
+#define SC27XX_FGU_CLBCNT_SETL 0x54
+#define SC27XX_FGU_CLBCNT_VALH 0x68
+#define SC27XX_FGU_CLBCNT_VALL 0x6c
+#define SC27XX_FGU_CLBCNT_QMAXL 0x74
+
+#define SC27XX_WRITE_SELCLB_EN BIT(0)
+#define SC27XX_FGU_CLBCNT_MASK GENMASK(15, 0)
+#define SC27XX_FGU_CLBCNT_SHIFT 16
+
+#define SC27XX_FGU_1000MV_ADC 686
+#define SC27XX_FGU_1000MA_ADC 1372
+#define SC27XX_FGU_CUR_BASIC_ADC 8192
+#define SC27XX_FGU_SAMPLE_HZ 2
+
+/*
+ * struct sc27xx_fgu_data: describe the FGU device
+ * @regmap: regmap for register access
+ * @dev: platform device
+ * @battery: battery power supply
+ * @base: the base offset for the controller
+ * @lock: protect the structure
+ * @gpiod: GPIO for battery detection
+ * @channel: IIO channel to get battery temperature
+ * @internal_resist: the battery internal resistance in mOhm
+ * @total_cap: the total capacity of the battery in mAh
+ * @init_cap: the initial capacity of the battery in mAh
+ * @init_clbcnt: the initial coulomb counter
+ * @max_volt: the maximum constant input voltage in millivolt
+ * @table_len: the capacity table length
+ * @cap_table: capacity table with corresponding ocv
+ */
+struct sc27xx_fgu_data {
+ struct regmap *regmap;
+ struct device *dev;
+ struct power_supply *battery;
+ u32 base;
+ struct mutex lock;
+ struct gpio_desc *gpiod;
+ struct iio_channel *channel;
+ bool bat_present;
+ int internal_resist;
+ int total_cap;
+ int init_cap;
+ int init_clbcnt;
+ int max_volt;
+ int table_len;
+ struct power_supply_battery_ocv_table *cap_table;
+};
+
+static const char * const sc27xx_charger_supply_name[] = {
+ "sc2731_charger",
+ "sc2720_charger",
+ "sc2721_charger",
+ "sc2723_charger",
+};
+
+static int sc27xx_fgu_adc_to_current(int adc)
+{
+ return (adc * 1000) / SC27XX_FGU_1000MA_ADC;
+}
+
+static int sc27xx_fgu_adc_to_voltage(int adc)
+{
+ return (adc * 1000) / SC27XX_FGU_1000MV_ADC;
+}
+
+/*
+ * When system boots on, we can not read battery capacity from coulomb
+ * registers, since now the coulomb registers are invalid. So we should
+ * calculate the battery open circuit voltage, and get current battery
+ * capacity according to the capacity table.
+ */
+static int sc27xx_fgu_get_boot_capacity(struct sc27xx_fgu_data *data, int *cap)
+{
+ int volt, cur, oci, ocv, ret;
+
+ /*
+ * After system booting on, the SC27XX_FGU_CLBCNT_QMAXL register saved
+ * the first sampled open circuit current.
+ */
+ ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_QMAXL,
+ &cur);
+ if (ret)
+ return ret;
+
+ cur <<= 1;
+ oci = sc27xx_fgu_adc_to_current(cur - SC27XX_FGU_CUR_BASIC_ADC);
+
+ /*
+ * Should get the OCV from SC27XX_FGU_POCV register at the system
+ * beginning. It is ADC values reading from registers which need to
+ * convert the corresponding voltage.
+ */
+ ret = regmap_read(data->regmap, data->base + SC27XX_FGU_POCV, &volt);
+ if (ret)
+ return ret;
+
+ volt = sc27xx_fgu_adc_to_voltage(volt);
+ ocv = volt - (oci * data->internal_resist) / 1000;
+
+ /*
+ * Parse the capacity table to look up the correct capacity percent
+ * according to current battery's corresponding OCV values.
+ */
+ *cap = power_supply_ocv2cap_simple(data->cap_table, data->table_len,
+ ocv);
+
+ return 0;
+}
+
+static int sc27xx_fgu_set_clbcnt(struct sc27xx_fgu_data *data, int clbcnt)
+{
+ int ret;
+
+ clbcnt *= SC27XX_FGU_SAMPLE_HZ;
+
+ ret = regmap_update_bits(data->regmap,
+ data->base + SC27XX_FGU_CLBCNT_SETL,
+ SC27XX_FGU_CLBCNT_MASK, clbcnt);
+ if (ret)
+ return ret;
+
+ ret = regmap_update_bits(data->regmap,
+ data->base + SC27XX_FGU_CLBCNT_SETH,
+ SC27XX_FGU_CLBCNT_MASK,
+ clbcnt >> SC27XX_FGU_CLBCNT_SHIFT);
+ if (ret)
+ return ret;
+
+ return regmap_update_bits(data->regmap, data->base + SC27XX_FGU_START,
+ SC27XX_WRITE_SELCLB_EN,
+ SC27XX_WRITE_SELCLB_EN);
+}
+
+static int sc27xx_fgu_get_clbcnt(struct sc27xx_fgu_data *data, int *clb_cnt)
+{
+ int ccl, cch, ret;
+
+ ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_VALL,
+ &ccl);
+ if (ret)
+ return ret;
+
+ ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_VALH,
+ &cch);
+ if (ret)
+ return ret;
+
+ *clb_cnt = ccl & SC27XX_FGU_CLBCNT_MASK;
+ *clb_cnt |= (cch & SC27XX_FGU_CLBCNT_MASK) << SC27XX_FGU_CLBCNT_SHIFT;
+ *clb_cnt /= SC27XX_FGU_SAMPLE_HZ;
+
+ return 0;
+}
+
+static int sc27xx_fgu_get_capacity(struct sc27xx_fgu_data *data, int *cap)
+{
+ int ret, cur_clbcnt, delta_clbcnt, delta_cap, temp;
+
+ /* Get current coulomb counters firstly */
+ ret = sc27xx_fgu_get_clbcnt(data, &cur_clbcnt);
+ if (ret)
+ return ret;
+
+ delta_clbcnt = cur_clbcnt - data->init_clbcnt;
+
+ /*
+ * Convert coulomb counter to delta capacity (mAh), and set multiplier
+ * as 100 to improve the precision.
+ */
+ temp = DIV_ROUND_CLOSEST(delta_clbcnt, 360);
+ temp = sc27xx_fgu_adc_to_current(temp);
+
+ /*
+ * Convert to capacity percent of the battery total capacity,
+ * and multiplier is 100 too.
+ */
+ delta_cap = DIV_ROUND_CLOSEST(temp * 100, data->total_cap);
+ *cap = delta_cap + data->init_cap;
+
+ return 0;
+}
+
+static int sc27xx_fgu_get_vbat_vol(struct sc27xx_fgu_data *data, int *val)
+{
+ int ret, vol;
+
+ ret = regmap_read(data->regmap, data->base + SC27XX_FGU_VOLTAGE, &vol);
+ if (ret)
+ return ret;
+
+ /*
+ * It is ADC values reading from registers which need to convert to
+ * corresponding voltage values.
+ */
+ *val = sc27xx_fgu_adc_to_voltage(vol);
+
+ return 0;
+}
+
+static int sc27xx_fgu_get_current(struct sc27xx_fgu_data *data, int *val)
+{
+ int ret, cur;
+
+ ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CURRENT, &cur);
+ if (ret)
+ return ret;
+
+ /*
+ * It is ADC values reading from registers which need to convert to
+ * corresponding current values.
+ */
+ *val = sc27xx_fgu_adc_to_current(cur - SC27XX_FGU_CUR_BASIC_ADC);
+
+ return 0;
+}
+
+static int sc27xx_fgu_get_vbat_ocv(struct sc27xx_fgu_data *data, int *val)
+{
+ int vol, cur, ret;
+
+ ret = sc27xx_fgu_get_vbat_vol(data, &vol);
+ if (ret)
+ return ret;
+
+ ret = sc27xx_fgu_get_current(data, &cur);
+ if (ret)
+ return ret;
+
+ /* Return the battery OCV in micro volts. */
+ *val = vol * 1000 - cur * data->internal_resist;
+
+ return 0;
+}
+
+static int sc27xx_fgu_get_temp(struct sc27xx_fgu_data *data, int *temp)
+{
+ return iio_read_channel_processed(data->channel, temp);
+}
+
+static int sc27xx_fgu_get_health(struct sc27xx_fgu_data *data, int *health)
+{
+ int ret, vol;
+
+ ret = sc27xx_fgu_get_vbat_vol(data, &vol);
+ if (ret)
+ return ret;
+
+ if (vol > data->max_volt)
+ *health = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
+ else
+ *health = POWER_SUPPLY_HEALTH_GOOD;
+
+ return 0;
+}
+
+static int sc27xx_fgu_get_status(struct sc27xx_fgu_data *data, int *status)
+{
+ union power_supply_propval val;
+ struct power_supply *psy;
+ int i, ret = -EINVAL;
+
+ for (i = 0; i < ARRAY_SIZE(sc27xx_charger_supply_name); i++) {
+ psy = power_supply_get_by_name(sc27xx_charger_supply_name[i]);
+ if (!psy)
+ continue;
+
+ ret = power_supply_get_property(psy, POWER_SUPPLY_PROP_STATUS,
+ &val);
+ power_supply_put(psy);
+ if (ret)
+ return ret;
+
+ *status = val.intval;
+ }
+
+ return ret;
+}
+
+static int sc27xx_fgu_get_property(struct power_supply *psy,
+ enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
+ int ret = 0;
+ int value;
+
+ mutex_lock(&data->lock);
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_STATUS:
+ ret = sc27xx_fgu_get_status(data, &value);
+ if (ret)
+ goto error;
+
+ val->intval = value;
+ break;
+
+ case POWER_SUPPLY_PROP_HEALTH:
+ ret = sc27xx_fgu_get_health(data, &value);
+ if (ret)
+ goto error;
+
+ val->intval = value;
+ break;
+
+ case POWER_SUPPLY_PROP_PRESENT:
+ val->intval = data->bat_present;
+ break;
+
+ case POWER_SUPPLY_PROP_TEMP:
+ ret = sc27xx_fgu_get_temp(data, &value);
+ if (ret)
+ goto error;
+
+ val->intval = value;
+ break;
+
+ case POWER_SUPPLY_PROP_TECHNOLOGY:
+ val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
+ break;
+
+ case POWER_SUPPLY_PROP_CAPACITY:
+ ret = sc27xx_fgu_get_capacity(data, &value);
+ if (ret)
+ goto error;
+
+ val->intval = value;
+ break;
+
+ case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+ ret = sc27xx_fgu_get_vbat_vol(data, &value);
+ if (ret)
+ goto error;
+
+ val->intval = value * 1000;
+ break;
+
+ case POWER_SUPPLY_PROP_VOLTAGE_OCV:
+ ret = sc27xx_fgu_get_vbat_ocv(data, &value);
+ if (ret)
+ goto error;
+
+ val->intval = value;
+ break;
+
+ case POWER_SUPPLY_PROP_CURRENT_NOW:
+ case POWER_SUPPLY_PROP_CURRENT_AVG:
+ ret = sc27xx_fgu_get_current(data, &value);
+ if (ret)
+ goto error;
+
+ val->intval = value * 1000;
+ break;
+
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+error:
+ mutex_unlock(&data->lock);
+ return ret;
+}
+
+static void sc27xx_fgu_external_power_changed(struct power_supply *psy)
+{
+ struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
+
+ power_supply_changed(data->battery);
+}
+
+static enum power_supply_property sc27xx_fgu_props[] = {
+ POWER_SUPPLY_PROP_STATUS,
+ POWER_SUPPLY_PROP_HEALTH,
+ POWER_SUPPLY_PROP_PRESENT,
+ POWER_SUPPLY_PROP_TEMP,
+ POWER_SUPPLY_PROP_TECHNOLOGY,
+ POWER_SUPPLY_PROP_CAPACITY,
+ POWER_SUPPLY_PROP_VOLTAGE_NOW,
+ POWER_SUPPLY_PROP_VOLTAGE_OCV,
+ POWER_SUPPLY_PROP_CURRENT_NOW,
+ POWER_SUPPLY_PROP_CURRENT_AVG,
+};
+
+static const struct power_supply_desc sc27xx_fgu_desc = {
+ .name = "sc27xx-fgu",
+ .type = POWER_SUPPLY_TYPE_BATTERY,
+ .properties = sc27xx_fgu_props,
+ .num_properties = ARRAY_SIZE(sc27xx_fgu_props),
+ .get_property = sc27xx_fgu_get_property,
+ .external_power_changed = sc27xx_fgu_external_power_changed,
+};
+
+static irqreturn_t sc27xx_fgu_bat_detection(int irq, void *dev_id)
+{
+ struct sc27xx_fgu_data *data = dev_id;
+ int state;
+
+ mutex_lock(&data->lock);
+
+ state = gpiod_get_value_cansleep(data->gpiod);
+ if (state < 0) {
+ dev_err(data->dev, "failed to get gpio state\n");
+ mutex_unlock(&data->lock);
+ return IRQ_RETVAL(state);
+ }
+
+ data->bat_present = !!state;
+
+ mutex_unlock(&data->lock);
+
+ power_supply_changed(data->battery);
+ return IRQ_HANDLED;
+}
+
+static void sc27xx_fgu_disable(void *_data)
+{
+ struct sc27xx_fgu_data *data = _data;
+
+ regmap_update_bits(data->regmap, SC27XX_CLK_EN0, SC27XX_FGU_RTC_EN, 0);
+ regmap_update_bits(data->regmap, SC27XX_MODULE_EN0, SC27XX_FGU_EN, 0);
+}
+
+static int sc27xx_fgu_cap_to_clbcnt(struct sc27xx_fgu_data *data, int capacity)
+{
+ /*
+ * Get current capacity (mAh) = battery total capacity (mAh) *
+ * current capacity percent (capacity / 100).
+ */
+ int cur_cap = DIV_ROUND_CLOSEST(data->total_cap * capacity, 100);
+
+ /*
+ * Convert current capacity (mAh) to coulomb counter according to the
+ * formula: 1 mAh =3.6 coulomb.
+ */
+ return DIV_ROUND_CLOSEST(cur_cap * 36, 10);
+}
+
+static int sc27xx_fgu_hw_init(struct sc27xx_fgu_data *data)
+{
+ struct power_supply_battery_info info = { };
+ struct power_supply_battery_ocv_table *table;
+ int ret, i;
+
+ ret = power_supply_get_battery_info(data->battery, &info);
+ if (ret) {
+ dev_err(data->dev, "failed to get battery information\n");
+ return ret;
+ }
+
+ data->total_cap = info.charge_full_design_uah / 1000;
+ data->max_volt = info.constant_charge_voltage_max_uv / 1000;
+ data->internal_resist = info.factory_internal_resistance_uohm / 1000;
+
+ /*
+ * For SC27XX fuel gauge device, we only use one ocv-capacity
+ * table in normal temperature 20 Celsius.
+ */
+ table = power_supply_find_ocv2cap_table(&info, 20, &data->table_len);
+ if (!table)
+ return -EINVAL;
+
+ data->cap_table = devm_kzalloc(data->dev,
+ data->table_len * sizeof(*table),
+ GFP_KERNEL);
+ if (!data->cap_table) {
+ power_supply_put_battery_info(data->battery, &info);
+ return -ENOMEM;
+ }
+
+ for (i = 0; i < data->table_len; i++) {
+ data->cap_table[i].ocv = table[i].ocv / 1000;
+ data->cap_table[i].capacity = table[i].capacity;
+ }
+
+ power_supply_put_battery_info(data->battery, &info);
+
+ /* Enable the FGU module */
+ ret = regmap_update_bits(data->regmap, SC27XX_MODULE_EN0,
+ SC27XX_FGU_EN, SC27XX_FGU_EN);
+ if (ret) {
+ dev_err(data->dev, "failed to enable fgu\n");
+ return ret;
+ }
+
+ /* Enable the FGU RTC clock to make it work */
+ ret = regmap_update_bits(data->regmap, SC27XX_CLK_EN0,
+ SC27XX_FGU_RTC_EN, SC27XX_FGU_RTC_EN);
+ if (ret) {
+ dev_err(data->dev, "failed to enable fgu RTC clock\n");
+ goto disable_fgu;
+ }
+
+ /*
+ * Get the boot battery capacity when system powers on, which is used to
+ * initialize the coulomb counter. After that, we can read the coulomb
+ * counter to measure the battery capacity.
+ */
+ ret = sc27xx_fgu_get_boot_capacity(data, &data->init_cap);
+ if (ret) {
+ dev_err(data->dev, "failed to get boot capacity\n");
+ goto disable_clk;
+ }
+
+ /*
+ * Convert battery capacity to the corresponding initial coulomb counter
+ * and set into coulomb counter registers.
+ */
+ data->init_clbcnt = sc27xx_fgu_cap_to_clbcnt(data, data->init_cap);
+ ret = sc27xx_fgu_set_clbcnt(data, data->init_clbcnt);
+ if (ret) {
+ dev_err(data->dev, "failed to initialize coulomb counter\n");
+ goto disable_clk;
+ }
+
+ return 0;
+
+disable_clk:
+ regmap_update_bits(data->regmap, SC27XX_CLK_EN0, SC27XX_FGU_RTC_EN, 0);
+disable_fgu:
+ regmap_update_bits(data->regmap, SC27XX_MODULE_EN0, SC27XX_FGU_EN, 0);
+
+ return ret;
+}
+
+static int sc27xx_fgu_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct power_supply_config fgu_cfg = { };
+ struct sc27xx_fgu_data *data;
+ int ret, irq;
+
+ data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+ if (!data->regmap) {
+ dev_err(&pdev->dev, "failed to get regmap\n");
+ return -ENODEV;
+ }
+
+ ret = device_property_read_u32(&pdev->dev, "reg", &data->base);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to get fgu address\n");
+ return ret;
+ }
+
+ data->channel = devm_iio_channel_get(&pdev->dev, "bat-temp");
+ if (IS_ERR(data->channel)) {
+ dev_err(&pdev->dev, "failed to get IIO channel\n");
+ return PTR_ERR(data->channel);
+ }
+
+ data->gpiod = devm_gpiod_get(&pdev->dev, "bat-detect", GPIOD_IN);
+ if (IS_ERR(data->gpiod)) {
+ dev_err(&pdev->dev, "failed to get battery detection GPIO\n");
+ return PTR_ERR(data->gpiod);
+ }
+
+ ret = gpiod_get_value_cansleep(data->gpiod);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to get gpio state\n");
+ return ret;
+ }
+
+ data->bat_present = !!ret;
+ mutex_init(&data->lock);
+ data->dev = &pdev->dev;
+
+ fgu_cfg.drv_data = data;
+ fgu_cfg.of_node = np;
+ data->battery = devm_power_supply_register(&pdev->dev, &sc27xx_fgu_desc,
+ &fgu_cfg);
+ if (IS_ERR(data->battery)) {
+ dev_err(&pdev->dev, "failed to register power supply\n");
+ return PTR_ERR(data->battery);
+ }
+
+ ret = sc27xx_fgu_hw_init(data);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to initialize fgu hardware\n");
+ return ret;
+ }
+
+ ret = devm_add_action(&pdev->dev, sc27xx_fgu_disable, data);
+ if (ret) {
+ sc27xx_fgu_disable(data);
+ dev_err(&pdev->dev, "failed to add fgu disable action\n");
+ return ret;
+ }
+
+ irq = gpiod_to_irq(data->gpiod);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "failed to translate GPIO to IRQ\n");
+ return irq;
+ }
+
+ ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
+ sc27xx_fgu_bat_detection,
+ IRQF_ONESHOT | IRQF_TRIGGER_RISING |
+ IRQF_TRIGGER_FALLING,
+ pdev->name, data);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to request IRQ\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id sc27xx_fgu_of_match[] = {
+ { .compatible = "sprd,sc2731-fgu", },
+ { }
+};
+
+static struct platform_driver sc27xx_fgu_driver = {
+ .probe = sc27xx_fgu_probe,
+ .driver = {
+ .name = "sc27xx-fgu",
+ .of_match_table = sc27xx_fgu_of_match,
+ }
+};
+
+module_platform_driver(sc27xx_fgu_driver);
+
+MODULE_DESCRIPTION("Spreadtrum SC27XX PMICs Fual Gauge Unit Driver");
+MODULE_LICENSE("GPL v2");
--
1.7.9.5