[PATCH v2] power: supply: sc27xx: Save last battery capacity
From: Baolin Wang
Date: Wed Dec 05 2018 - 22:21:07 EST
From: Yuanjiang Yu <yuanjiang.yu@xxxxxxxxxx>
Our charger manager can optimize the battery capacity periodically, so
we can save last battery capacity into registers. Then next system
power-on, we can read the last saved battery capacity as the initial
battery capacity, which can make the battery capacity more accurate.
Signed-off-by: Yuanjiang Yu <yuanjiang.yu@xxxxxxxxxx>
Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
---
Changes from v1:
- Simplify the logics for sc27xx_fgu_set_property() and
sc27xx_fgu_property_is_writeable().
---
drivers/power/supply/sc27xx_fuel_gauge.c | 135 +++++++++++++++++++++++++++++-
1 file changed, 134 insertions(+), 1 deletion(-)
diff --git a/drivers/power/supply/sc27xx_fuel_gauge.c b/drivers/power/supply/sc27xx_fuel_gauge.c
index 8c52e29..76da189 100644
--- a/drivers/power/supply/sc27xx_fuel_gauge.c
+++ b/drivers/power/supply/sc27xx_fuel_gauge.c
@@ -39,6 +39,9 @@
#define SC27XX_FGU_CLBCNT_VALH 0x68
#define SC27XX_FGU_CLBCNT_VALL 0x6c
#define SC27XX_FGU_CLBCNT_QMAXL 0x74
+#define SC27XX_FGU_USER_AREA_SET 0xa0
+#define SC27XX_FGU_USER_AREA_CLEAR 0xa4
+#define SC27XX_FGU_USER_AREA_STATUS 0xa8
#define SC27XX_WRITE_SELCLB_EN BIT(0)
#define SC27XX_FGU_CLBCNT_MASK GENMASK(15, 0)
@@ -49,6 +52,14 @@
#define SC27XX_FGU_LOW_OVERLOAD_INT BIT(0)
#define SC27XX_FGU_CLBCNT_DELTA_INT BIT(2)
+#define SC27XX_FGU_MODE_AREA_MASK GENMASK(15, 12)
+#define SC27XX_FGU_CAP_AREA_MASK GENMASK(11, 0)
+#define SC27XX_FGU_MODE_AREA_SHIFT 12
+
+#define SC27XX_FGU_FIRST_POWERTON GENMASK(3, 0)
+#define SC27XX_FGU_DEFAULT_CAP GENMASK(11, 0)
+#define SC27XX_FGU_NORMAIL_POWERTON 0x5
+
#define SC27XX_FGU_CUR_BASIC_ADC 8192
#define SC27XX_FGU_SAMPLE_HZ 2
@@ -119,6 +130,80 @@ static int sc27xx_fgu_voltage_to_adc(struct sc27xx_fgu_data *data, int vol)
return DIV_ROUND_CLOSEST(vol * data->vol_1000mv_adc, 1000);
}
+static bool sc27xx_fgu_is_first_poweron(struct sc27xx_fgu_data *data)
+{
+ int ret, status, cap, mode;
+
+ ret = regmap_read(data->regmap,
+ data->base + SC27XX_FGU_USER_AREA_STATUS, &status);
+ if (ret)
+ return false;
+
+ /*
+ * We use low 4 bits to save the last battery capacity and high 12 bits
+ * to save the system boot mode.
+ */
+ mode = (status & SC27XX_FGU_MODE_AREA_MASK) >> SC27XX_FGU_MODE_AREA_SHIFT;
+ cap = status & SC27XX_FGU_CAP_AREA_MASK;
+
+ /*
+ * When FGU has been powered down, the user area registers became
+ * default value (0xffff), which can be used to valid if the system is
+ * first power on or not.
+ */
+ if (mode == SC27XX_FGU_FIRST_POWERTON || cap == SC27XX_FGU_DEFAULT_CAP)
+ return true;
+
+ return false;
+}
+
+static int sc27xx_fgu_save_boot_mode(struct sc27xx_fgu_data *data,
+ int boot_mode)
+{
+ int ret;
+
+ ret = regmap_update_bits(data->regmap,
+ data->base + SC27XX_FGU_USER_AREA_CLEAR,
+ SC27XX_FGU_MODE_AREA_MASK,
+ SC27XX_FGU_MODE_AREA_MASK);
+ if (ret)
+ return ret;
+
+ return regmap_update_bits(data->regmap,
+ data->base + SC27XX_FGU_USER_AREA_SET,
+ SC27XX_FGU_MODE_AREA_MASK,
+ boot_mode << SC27XX_FGU_MODE_AREA_SHIFT);
+}
+
+static int sc27xx_fgu_save_last_cap(struct sc27xx_fgu_data *data, int cap)
+{
+ int ret;
+
+ ret = regmap_update_bits(data->regmap,
+ data->base + SC27XX_FGU_USER_AREA_CLEAR,
+ SC27XX_FGU_CAP_AREA_MASK,
+ SC27XX_FGU_CAP_AREA_MASK);
+ if (ret)
+ return ret;
+
+ return regmap_update_bits(data->regmap,
+ data->base + SC27XX_FGU_USER_AREA_SET,
+ SC27XX_FGU_CAP_AREA_MASK, cap);
+}
+
+static int sc27xx_fgu_read_last_cap(struct sc27xx_fgu_data *data, int *cap)
+{
+ int ret, value;
+
+ ret = regmap_read(data->regmap,
+ data->base + SC27XX_FGU_USER_AREA_STATUS, &value);
+ if (ret)
+ return ret;
+
+ *cap = value & SC27XX_FGU_CAP_AREA_MASK;
+ return 0;
+}
+
/*
* When system boots on, we can not read battery capacity from coulomb
* registers, since now the coulomb registers are invalid. So we should
@@ -128,6 +213,20 @@ static int sc27xx_fgu_voltage_to_adc(struct sc27xx_fgu_data *data, int vol)
static int sc27xx_fgu_get_boot_capacity(struct sc27xx_fgu_data *data, int *cap)
{
int volt, cur, oci, ocv, ret;
+ bool is_first_poweron = sc27xx_fgu_is_first_poweron(data);
+
+ /*
+ * If system is not the first power on, we should use the last saved
+ * battery capacity as the initial battery capacity. Otherwise we should
+ * re-calculate the initial battery capacity.
+ */
+ if (!is_first_poweron) {
+ ret = sc27xx_fgu_read_last_cap(data, cap);
+ if (ret)
+ return ret;
+
+ return sc27xx_fgu_save_boot_mode(data, SC27XX_FGU_NORMAIL_POWERTON);
+ }
/*
* After system booting on, the SC27XX_FGU_CLBCNT_QMAXL register saved
@@ -160,7 +259,11 @@ static int sc27xx_fgu_get_boot_capacity(struct sc27xx_fgu_data *data, int *cap)
*cap = power_supply_ocv2cap_simple(data->cap_table, data->table_len,
ocv);
- return 0;
+ ret = sc27xx_fgu_save_last_cap(data, *cap);
+ if (ret)
+ return ret;
+
+ return sc27xx_fgu_save_boot_mode(data, SC27XX_FGU_NORMAIL_POWERTON);
}
static int sc27xx_fgu_set_clbcnt(struct sc27xx_fgu_data *data, int clbcnt)
@@ -418,6 +521,28 @@ static int sc27xx_fgu_get_property(struct power_supply *psy,
return ret;
}
+static int sc27xx_fgu_set_property(struct power_supply *psy,
+ enum power_supply_property psp,
+ const union power_supply_propval *val)
+{
+ struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
+ int ret;
+
+ if (psp != POWER_SUPPLY_PROP_CAPACITY)
+ return -EINVAL;
+
+ mutex_lock(&data->lock);
+
+ ret = sc27xx_fgu_save_last_cap(data, val->intval);
+
+ mutex_unlock(&data->lock);
+
+ if (ret < 0)
+ dev_err(data->dev, "failed to save battery capacity\n");
+
+ return ret;
+}
+
static void sc27xx_fgu_external_power_changed(struct power_supply *psy)
{
struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
@@ -425,6 +550,12 @@ static void sc27xx_fgu_external_power_changed(struct power_supply *psy)
power_supply_changed(data->battery);
}
+static int sc27xx_fgu_property_is_writeable(struct power_supply *psy,
+ enum power_supply_property psp)
+{
+ return psp == POWER_SUPPLY_PROP_CAPACITY;
+}
+
static enum power_supply_property sc27xx_fgu_props[] = {
POWER_SUPPLY_PROP_STATUS,
POWER_SUPPLY_PROP_HEALTH,
@@ -444,7 +575,9 @@ static void sc27xx_fgu_external_power_changed(struct power_supply *psy)
.properties = sc27xx_fgu_props,
.num_properties = ARRAY_SIZE(sc27xx_fgu_props),
.get_property = sc27xx_fgu_get_property,
+ .set_property = sc27xx_fgu_set_property,
.external_power_changed = sc27xx_fgu_external_power_changed,
+ .property_is_writeable = sc27xx_fgu_property_is_writeable,
};
static void sc27xx_fgu_adjust_cap(struct sc27xx_fgu_data *data, int cap)
--
1.7.9.5