The max8998 has a current regulator for charging control. The
charger driver in drivers/power/supply/max8998_charger.c has a
comment in it stating that 'charger control is done by a current
regulator "CHARGER"', but this regulator was never added until
now.
The current values have been extracted from a downstream driver
for the SGH-T959V.
Signed-off-by: Jonathan Bakker <xc-racer2@xxxxxxx>
---
drivers/regulator/max8998.c | 105 ++++++++++++++++++++++++++++++++++++
include/linux/mfd/max8998.h | 1 +
2 files changed, 106 insertions(+)
diff --git a/drivers/regulator/max8998.c b/drivers/regulator/max8998.c
index 60599c3bb845..668ced006417 100644
--- a/drivers/regulator/max8998.c
+++ b/drivers/regulator/max8998.c
@@ -33,6 +33,10 @@ struct max8998_data {
unsigned int buck2_idx;
};
+static const unsigned int charger_current_table[] = {
+ 90000, 380000, 475000, 550000, 570000, 600000, 700000, 800000,
+};
+
static int max8998_get_enable_register(struct regulator_dev *rdev,
int *reg, int *shift)
{
@@ -63,6 +67,10 @@ static int max8998_get_enable_register(struct regulator_dev *rdev,
*reg = MAX8998_REG_CHGR2;
*shift = 7 - (ldo - MAX8998_ESAFEOUT1);
break;
+ case MAX8998_CHARGER:
+ *reg = MAX8998_REG_CHGR2;
+ *shift = 0;
+ break;
default:
return -EINVAL;
}
@@ -88,6 +96,11 @@ static int max8998_ldo_is_enabled(struct regulator_dev *rdev)
return val & (1 << shift);
}
+static int max8998_ldo_is_enabled_inverted(struct regulator_dev *rdev)
+{
+ return (!max8998_ldo_is_enabled(rdev));
+}
+
static int max8998_ldo_enable(struct regulator_dev *rdev)
{
struct max8998_data *max8998 = rdev_get_drvdata(rdev);
@@ -358,6 +371,74 @@ static int max8998_set_voltage_buck_time_sel(struct regulator_dev *rdev,
return 0;
}
+int max8998_set_current_limit(struct regulator_dev *rdev,
+ int min_uA, int max_uA)
+{
+ struct max8998_data *max8998 = rdev_get_drvdata(rdev);
+ struct i2c_client *i2c = max8998->iodev->i2c;
+ unsigned int n_currents = rdev->desc->n_current_limits;
+ int i, sel = -1;
+
+ if (n_currents == 0)
+ return -EINVAL;
+
+ if (rdev->desc->curr_table) {
+ const unsigned int *curr_table = rdev->desc->curr_table;
+ bool ascend = curr_table[n_currents - 1] > curr_table[0];
+
+ /* search for closest to maximum */
+ if (ascend) {
+ for (i = n_currents - 1; i >= 0; i--) {
+ if (min_uA <= curr_table[i] &&
+ curr_table[i] <= max_uA) {
+ sel = i;
+ break;
+ }
+ }
+ } else {
+ for (i = 0; i < n_currents; i++) {
+ if (min_uA <= curr_table[i] &&
+ curr_table[i] <= max_uA) {
+ sel = i;
+ break;
+ }
+ }
+ }
+ }
+
+ if (sel < 0)
+ return -EINVAL;
+
+ sel <<= ffs(rdev->desc->csel_mask) - 1;
+
+ return max8998_update_reg(i2c, rdev->desc->csel_reg,
+ sel, rdev->desc->csel_mask);
+}
+
+int max8998_get_current_limit(struct regulator_dev *rdev)
+{
+ struct max8998_data *max8998 = rdev_get_drvdata(rdev);
+ struct i2c_client *i2c = max8998->iodev->i2c;
+ u8 val;
+ int ret;
+
+ ret = max8998_read_reg(i2c, rdev->desc->csel_reg, &val);
+ if (ret != 0)
+ return ret;
+
+ val &= rdev->desc->csel_mask;
+ val >>= ffs(rdev->desc->csel_mask) - 1;
+
+ if (rdev->desc->curr_table) {
+ if (val >= rdev->desc->n_current_limits)
+ return -EINVAL;
+
+ return rdev->desc->curr_table[val];
+ }
+
+ return -EINVAL;
+}
+
static const struct regulator_ops max8998_ldo_ops = {
.list_voltage = regulator_list_voltage_linear,
.map_voltage = regulator_map_voltage_linear,
@@ -379,6 +460,15 @@ static const struct regulator_ops max8998_buck_ops = {
.set_voltage_time_sel = max8998_set_voltage_buck_time_sel,
};
+static const struct regulator_ops max8998_charger_ops = {
+ .set_current_limit = max8998_set_current_limit,
+ .get_current_limit = max8998_get_current_limit,
+ .is_enabled = max8998_ldo_is_enabled_inverted,
+ /* Swapped as register is inverted */
+ .enable = max8998_ldo_disable,
+ .disable = max8998_ldo_enable,
+};
+
static const struct regulator_ops max8998_others_ops = {
.is_enabled = max8998_ldo_is_enabled,
.enable = max8998_ldo_enable,
@@ -397,6 +487,19 @@ static const struct regulator_ops max8998_others_ops = {
.owner = THIS_MODULE, \
}
+#define MAX8998_CURRENT_REG(_name, _ops, _table, _reg, _mask) \
+ { \
+ .name = #_name, \
+ .id = MAX8998_##_name, \
+ .ops = _ops, \
+ .curr_table = _table, \
+ .n_current_limits = ARRAY_SIZE(_table), \
+ .csel_reg = _reg, \
+ .csel_mask = _mask, \
+ .type = REGULATOR_CURRENT, \
+ .owner = THIS_MODULE, \
+ }
+
#define MAX8998_OTHERS_REG(_name, _id) \
{ \
.name = #_name, \
@@ -432,6 +535,8 @@ static const struct regulator_desc regulators[] = {
MAX8998_OTHERS_REG(ENVICHG, MAX8998_ENVICHG),
MAX8998_OTHERS_REG(ESAFEOUT1, MAX8998_ESAFEOUT1),
MAX8998_OTHERS_REG(ESAFEOUT2, MAX8998_ESAFEOUT2),
+ MAX8998_CURRENT_REG(CHARGER, &max8998_charger_ops,
+ charger_current_table, MAX8998_REG_CHGR1, 0x7),
};
static int max8998_pmic_dt_parse_dvs_gpio(struct max8998_dev *iodev,
diff --git a/include/linux/mfd/max8998.h b/include/linux/mfd/max8998.h
index 061af220dcd3..79c020bd0c70 100644
--- a/include/linux/mfd/max8998.h
+++ b/include/linux/mfd/max8998.h
@@ -39,6 +39,7 @@ enum {
MAX8998_ENVICHG,
MAX8998_ESAFEOUT1,
MAX8998_ESAFEOUT2,
+ MAX8998_CHARGER,
};
/**
--
2.20.1
