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path: root/drivers/power/supply/sc27xx_fuel_gauge.c
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Diffstat (limited to 'drivers/power/supply/sc27xx_fuel_gauge.c')
-rw-r--r--drivers/power/supply/sc27xx_fuel_gauge.c49
1 files changed, 46 insertions, 3 deletions
diff --git a/drivers/power/supply/sc27xx_fuel_gauge.c b/drivers/power/supply/sc27xx_fuel_gauge.c
index bc8f5bda5762..469c83fdaa8e 100644
--- a/drivers/power/supply/sc27xx_fuel_gauge.c
+++ b/drivers/power/supply/sc27xx_fuel_gauge.c
@@ -62,6 +62,8 @@
#define SC27XX_FGU_CUR_BASIC_ADC 8192
#define SC27XX_FGU_SAMPLE_HZ 2
+/* micro Ohms */
+#define SC27XX_FGU_IDEAL_RESISTANCE 20000
/*
* struct sc27xx_fgu_data: describe the FGU device
@@ -81,9 +83,12 @@
* @max_volt: the maximum constant input voltage in millivolt
* @min_volt: the minimum drained battery voltage in microvolt
* @table_len: the capacity table length
+ * @resist_table_len: the resistance table length
* @cur_1000ma_adc: ADC value corresponding to 1000 mA
* @vol_1000mv_adc: ADC value corresponding to 1000 mV
+ * @calib_resist: the real resistance of coulomb counter chip in uOhm
* @cap_table: capacity table with corresponding ocv
+ * @resist_table: resistance percent table with corresponding temperature
*/
struct sc27xx_fgu_data {
struct regmap *regmap;
@@ -103,15 +108,19 @@ struct sc27xx_fgu_data {
int max_volt;
int min_volt;
int table_len;
+ int resist_table_len;
int cur_1000ma_adc;
int vol_1000mv_adc;
+ int calib_resist;
struct power_supply_battery_ocv_table *cap_table;
+ struct power_supply_resistance_temp_table *resist_table;
};
static int sc27xx_fgu_cap_to_clbcnt(struct sc27xx_fgu_data *data, int capacity);
static void sc27xx_fgu_capacity_calibration(struct sc27xx_fgu_data *data,
int cap, bool int_mode);
static void sc27xx_fgu_adjust_cap(struct sc27xx_fgu_data *data, int cap);
+static int sc27xx_fgu_get_temp(struct sc27xx_fgu_data *data, int *temp);
static const char * const sc27xx_charger_supply_name[] = {
"sc2731_charger",
@@ -434,7 +443,7 @@ static int sc27xx_fgu_get_current(struct sc27xx_fgu_data *data, int *val)
static int sc27xx_fgu_get_vbat_ocv(struct sc27xx_fgu_data *data, int *val)
{
- int vol, cur, ret;
+ int vol, cur, ret, temp, resistance;
ret = sc27xx_fgu_get_vbat_vol(data, &vol);
if (ret)
@@ -444,8 +453,19 @@ static int sc27xx_fgu_get_vbat_ocv(struct sc27xx_fgu_data *data, int *val)
if (ret)
return ret;
+ resistance = data->internal_resist;
+ if (data->resist_table_len > 0) {
+ ret = sc27xx_fgu_get_temp(data, &temp);
+ if (ret)
+ return ret;
+
+ resistance = power_supply_temp2resist_simple(data->resist_table,
+ data->resist_table_len, temp);
+ resistance = data->internal_resist * resistance / 100;
+ }
+
/* Return the battery OCV in micro volts. */
- *val = vol * 1000 - cur * data->internal_resist;
+ *val = vol * 1000 - cur * resistance;
return 0;
}
@@ -884,7 +904,9 @@ static int sc27xx_fgu_calibration(struct sc27xx_fgu_data *data)
*/
cal_4200mv = (calib_data & 0x1ff) + 6963 - 4096 - 256;
data->vol_1000mv_adc = DIV_ROUND_CLOSEST(cal_4200mv * 10, 42);
- data->cur_1000ma_adc = data->vol_1000mv_adc * 4;
+ data->cur_1000ma_adc =
+ DIV_ROUND_CLOSEST(data->vol_1000mv_adc * 4 * data->calib_resist,
+ SC27XX_FGU_IDEAL_RESISTANCE);
kfree(buf);
return 0;
@@ -929,6 +951,18 @@ static int sc27xx_fgu_hw_init(struct sc27xx_fgu_data *data)
if (!data->alarm_cap)
data->alarm_cap += 1;
+ data->resist_table_len = info.resist_table_size;
+ if (data->resist_table_len > 0) {
+ data->resist_table = devm_kmemdup(data->dev, info.resist_table,
+ data->resist_table_len *
+ sizeof(struct power_supply_resistance_temp_table),
+ GFP_KERNEL);
+ if (!data->resist_table) {
+ power_supply_put_battery_info(data->battery, &info);
+ return -ENOMEM;
+ }
+ }
+
power_supply_put_battery_info(data->battery, &info);
ret = sc27xx_fgu_calibration(data);
@@ -1051,6 +1085,15 @@ static int sc27xx_fgu_probe(struct platform_device *pdev)
return ret;
}
+ ret = device_property_read_u32(&pdev->dev,
+ "sprd,calib-resistance-micro-ohms",
+ &data->calib_resist);
+ if (ret) {
+ dev_err(&pdev->dev,
+ "failed to get fgu calibration resistance\n");
+ return ret;
+ }
+
data->channel = devm_iio_channel_get(dev, "bat-temp");
if (IS_ERR(data->channel)) {
dev_err(dev, "failed to get IIO channel\n");