From: Yuanjiang Yu <yuanjiang...@unisoc.com>
Add low voltage alarm support to make sure the battery capacity
more accurate in lower voltage stage.
Signed-off-by: Yuanjiang Yu <yuanjiang...@unisoc.com>
Signed-off-by: Baolin Wang <baolin.w...@linaro.org>
---
drivers/power/supply/sc27xx_fuel_gauge.c | 171 +++++++++++++++++++++++++++++-
1 file changed, 170 insertions(+), 1 deletion(-)
diff --git a/drivers/power/supply/sc27xx_fuel_gauge.c
b/drivers/power/supply/sc27xx_fuel_gauge.c
index 66f4db2..962d0f8 100644
--- a/drivers/power/supply/sc27xx_fuel_gauge.c
+++ b/drivers/power/supply/sc27xx_fuel_gauge.c
@@ -31,8 +31,11 @@
#define SC27XX_FGU_OCV 0x24
#define SC27XX_FGU_POCV 0x28
#define SC27XX_FGU_CURRENT 0x2c
+#define SC27XX_FGU_LOW_OVERLOAD 0x34
#define SC27XX_FGU_CLBCNT_SETH 0x50
#define SC27XX_FGU_CLBCNT_SETL 0x54
+#define SC27XX_FGU_CLBCNT_DELTH 0x58
+#define SC27XX_FGU_CLBCNT_DELTL 0x5c
#define SC27XX_FGU_CLBCNT_VALH 0x68
#define SC27XX_FGU_CLBCNT_VALL 0x6c
#define SC27XX_FGU_CLBCNT_QMAXL 0x74
@@ -40,6 +43,11 @@
#define SC27XX_WRITE_SELCLB_EN BIT(0)
#define SC27XX_FGU_CLBCNT_MASK GENMASK(15, 0)
#define SC27XX_FGU_CLBCNT_SHIFT 16
+#define SC27XX_FGU_LOW_OVERLOAD_MASK GENMASK(12, 0)
+
+#define SC27XX_FGU_INT_MASK GENMASK(9, 0)
+#define SC27XX_FGU_LOW_OVERLOAD_INT BIT(0)
+#define SC27XX_FGU_CLBCNT_DELTA_INT BIT(2)
#define SC27XX_FGU_CUR_BASIC_ADC 8192
#define SC27XX_FGU_SAMPLE_HZ 2
@@ -56,8 +64,10 @@
* @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
+ * @alarm_cap: the alarm capacity
* @init_clbcnt: the initial coulomb counter
* @max_volt: the maximum constant input voltage in millivolt
+ * @min_volt: the minimum drained battery voltage in microvolt
* @table_len: the capacity table length
* @cur_1000ma_adc: ADC value corresponding to 1000 mA
* @vol_1000mv_adc: ADC value corresponding to 1000 mV
@@ -75,14 +85,18 @@ struct sc27xx_fgu_data {
int internal_resist;
int total_cap;
int init_cap;
+ int alarm_cap;
int init_clbcnt;
int max_volt;
+ int min_volt;
int table_len;
int cur_1000ma_adc;
int vol_1000mv_adc;
struct power_supply_battery_ocv_table *cap_table;
};
+static int sc27xx_fgu_cap_to_clbcnt(struct sc27xx_fgu_data *data, int
capacity);
+
static const char * const sc27xx_charger_supply_name[] = {
"sc2731_charger",
"sc2720_charger",
@@ -100,6 +114,11 @@ static int sc27xx_fgu_adc_to_voltage(struct
sc27xx_fgu_data *data, int adc)
return DIV_ROUND_CLOSEST(adc * 1000, data->vol_1000mv_adc);
}
+static int sc27xx_fgu_voltage_to_adc(struct sc27xx_fgu_data *data, int vol)
+{
+ return DIV_ROUND_CLOSEST(vol * data->vol_1000mv_adc, 1000);
+}
+
/*
* When system boots on, we can not read battery capacity from coulomb
* registers, since now the coulomb registers are invalid. So we should
@@ -428,6 +447,92 @@ static void sc27xx_fgu_external_power_changed(struct
power_supply *psy)
.external_power_changed = sc27xx_fgu_external_power_changed,
};
+static void sc27xx_fgu_adjust_cap(struct sc27xx_fgu_data *data, int cap)
+{
+ data->init_cap = cap;
+ data->init_clbcnt = sc27xx_fgu_cap_to_clbcnt(data, data->init_cap);
+}
+
+static irqreturn_t sc27xx_fgu_interrupt(int irq, void *dev_id)
+{
+ struct sc27xx_fgu_data *data = dev_id;
+ int ret, cap, ocv, adc;
+ u32 status;
+
+ mutex_lock(&data->lock);
+
+ ret = regmap_read(data->regmap, data->base + SC27XX_FGU_INT_STS,
+ &status);
+ if (ret)
+ goto out;
+
+ ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_INT_CLR,
+ status, status);
+ if (ret)
+ goto out;
+
+ /*
+ * When low overload voltage interrupt happens, we should calibrate the
+ * battery capacity in lower voltage stage.
+ */
+ if (!(status & SC27XX_FGU_LOW_OVERLOAD_INT))
+ goto out;
+
+ ret = sc27xx_fgu_get_capacity(data, &cap);
+ if (ret)
+ goto out;
+
+ ret = sc27xx_fgu_get_vbat_ocv(data, &ocv);
+ if (ret)
+ goto out;
+
+ /*
+ * If current OCV value is less than the minimum OCV value in OCV table,
+ * which means now battery capacity is 0%, and we should adjust the
+ * inititial capacity to 0.
+ */
+ if (ocv <= data->cap_table[data->table_len - 1].ocv) {
+ sc27xx_fgu_adjust_cap(data, 0);
+ } else if (ocv <= data->min_volt) {
+ /*
+ * If current OCV value is less than the low alarm voltage, but
+ * current capacity is larger than the alarm capacity, we should
+ * adjust the inititial capacity to alarm capacity.
+ */
+ if (cap > data->alarm_cap) {
+ sc27xx_fgu_adjust_cap(data, data->alarm_cap);
+ } else if (cap <= 0) {
+ int cur_cap;
+
+ /*
+ * If current capacity is equal with 0 or less than 0
+ * (some error occurs), we should adjust inititial
+ * capacity to the capacity corresponding to current OCV
+ * value.
+ */
+ cur_cap = power_supply_ocv2cap_simple(data->cap_table,
+ data->table_len,
+ ocv);
+ sc27xx_fgu_adjust_cap(data, cur_cap);
+ }
+
+ /*
+ * After adjusting the battery capacity, we should set the
+ * lowest alarm voltage instead.
+ */
+ data->min_volt = data->cap_table[data->table_len - 1].ocv;
+ adc = sc27xx_fgu_voltage_to_adc(data, data->min_volt / 1000);
+ regmap_update_bits(data->regmap, data->base +
SC27XX_FGU_LOW_OVERLOAD,
+ SC27XX_FGU_LOW_OVERLOAD_MASK, adc);
+ }
+
+out:
+ mutex_unlock(&data->lock);
+
+ power_supply_changed(data->battery);
+ return IRQ_HANDLED;
+}
+
static irqreturn_t sc27xx_fgu_bat_detection(int irq, void *dev_id)
{
struct sc27xx_fgu_data *data = dev_id;
@@ -509,7 +614,7 @@ 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;
+ int ret, delta_clbcnt, alarm_adc;
ret = power_supply_get_battery_info(data->battery, &info);
if (ret) {
@@ -520,6 +625,7 @@ static int sc27xx_fgu_hw_init(struct sc27xx_fgu_data *data)
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;
+ data->min_volt = info.voltage_min_design_uv;
/*
* For SC27XX fuel gauge device, we only use one ocv-capacity
@@ -537,6 +643,10 @@ static int sc27xx_fgu_hw_init(struct sc27xx_fgu_data *data)
return -ENOMEM;
}
+ data->alarm_cap = power_supply_ocv2cap_simple(data->cap_table,
+ data->table_len,
+ data->min_volt);
+
power_supply_put_battery_info(data->battery, &info);
ret = sc27xx_fgu_calibration(data);
@@ -559,6 +669,50 @@ static int sc27xx_fgu_hw_init(struct sc27xx_fgu_data *data)
goto disable_fgu;
}
+ ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_INT_CLR,
+ SC27XX_FGU_INT_MASK, SC27XX_FGU_INT_MASK);
+ if (ret) {
+ dev_err(data->dev, "failed to clear interrupt status\n");
+ goto disable_clk;
+ }
+
+ /*
+ * Set the voltage low overload threshold, which means when the battery
+ * voltage is lower than this threshold, the controller will generate
+ * one interrupt to notify.
+ */
+ alarm_adc = sc27xx_fgu_voltage_to_adc(data, data->min_volt / 1000);
+ ret = regmap_update_bits(data->regmap, data->base +
SC27XX_FGU_LOW_OVERLOAD,
+ SC27XX_FGU_LOW_OVERLOAD_MASK, alarm_adc);
+ if (ret) {
+ dev_err(data->dev, "failed to set fgu low overload\n");
+ goto disable_clk;
+ }
+
+ /*
+ * Set the coulomb counter delta threshold, that means when the coulomb
+ * counter change is multiples of the delta threshold, the controller
+ * will generate one interrupt to notify the users to update the battery
+ * capacity. Now we set the delta threshold as a counter value of 1%
+ * capacity.
+ */
+ delta_clbcnt = sc27xx_fgu_cap_to_clbcnt(data, 1);
+
+ ret = regmap_update_bits(data->regmap, data->base +
SC27XX_FGU_CLBCNT_DELTL,
+ SC27XX_FGU_CLBCNT_MASK, delta_clbcnt);
+ if (ret) {
+ dev_err(data->dev, "failed to set low delta coulomb counter\n");
+ goto disable_clk;
+ }
+
+ ret = regmap_update_bits(data->regmap, data->base +
SC27XX_FGU_CLBCNT_DELTH,
+ SC27XX_FGU_CLBCNT_MASK,
+ delta_clbcnt >> SC27XX_FGU_CLBCNT_SHIFT);
+ if (ret) {
+ dev_err(data->dev, "failed to set high delta coulomb
counter\n");
+ goto disable_clk;
+ }
+
/*
* Get the boot battery capacity when system powers on, which is used to
* initialize the coulomb counter. After that, we can read the coulomb
@@ -658,6 +812,21 @@ static int sc27xx_fgu_probe(struct platform_device *pdev)
return ret;
}
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "no irq resource specified\n");
+ return irq;
+ }
+
+ ret = devm_request_threaded_irq(data->dev, irq, NULL,
+ sc27xx_fgu_interrupt,
+ IRQF_NO_SUSPEND | IRQF_ONESHOT,
+ pdev->name, data);
+ if (ret) {
+ dev_err(data->dev, "failed to request fgu IRQ\n");
+ return ret;
+ }
+
irq = gpiod_to_irq(data->gpiod);
if (irq < 0) {
dev_err(&pdev->dev, "failed to translate GPIO to IRQ\n");
--
1.7.9.5
