[PATCH 02/11] regulator: core: Add set/get_current_limit helpers for regmap users

From: Axel Lin
Date: Thu Feb 28 2019 - 08:40:54 EST


By setting curr_table, n_current_limits, csel_reg and csel_mask, the
regmap users can use regulator_set_current_limit_regmap and
regulator_get_current_limit_regmap for set/get_current_limit callbacks.

Signed-off-by: Axel Lin <axel.lin@xxxxxxxxxx>
---
drivers/regulator/helpers.c | 86 ++++++++++++++++++++++++++++++++
include/linux/regulator/driver.h | 7 +++
2 files changed, 93 insertions(+)

diff --git a/drivers/regulator/helpers.c b/drivers/regulator/helpers.c
index 68ac6017ef28..09b316559ef6 100644
--- a/drivers/regulator/helpers.c
+++ b/drivers/regulator/helpers.c
@@ -780,3 +780,89 @@ int regulator_set_active_discharge_regmap(struct regulator_dev *rdev,
rdev->desc->active_discharge_mask, val);
}
EXPORT_SYMBOL_GPL(regulator_set_active_discharge_regmap);
+
+/**
+ * regulator_set_current_limit_regmap - set_current_limit for regmap users
+ *
+ * @rdev: regulator to operate on
+ * @min_uA: Lower bound for current limit
+ * @max_uA: Upper bound for current limit
+ *
+ * Regulators that use regmap for their register I/O can set curr_table,
+ * csel_reg and csel_mask fields in their descriptor and then use this
+ * as their set_current_limit operation, saving some code.
+ */
+int regulator_set_current_limit_regmap(struct regulator_dev *rdev,
+ int min_uA, int max_uA)
+{
+ 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 regmap_update_bits(rdev->regmap, rdev->desc->csel_reg,
+ rdev->desc->csel_mask, sel);
+}
+EXPORT_SYMBOL_GPL(regulator_set_current_limit_regmap);
+
+/**
+ * regulator_get_current_limit_regmap - get_current_limit for regmap users
+ *
+ * @rdev: regulator to operate on
+ *
+ * Regulators that use regmap for their register I/O can set the
+ * csel_reg and csel_mask fields in their descriptor and then use this
+ * as their get_current_limit operation, saving some code.
+ */
+int regulator_get_current_limit_regmap(struct regulator_dev *rdev)
+{
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(rdev->regmap, 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;
+}
+EXPORT_SYMBOL_GPL(regulator_get_current_limit_regmap);
diff --git a/include/linux/regulator/driver.h b/include/linux/regulator/driver.h
index a0b9df5f60e0..c3dff2272664 100644
--- a/include/linux/regulator/driver.h
+++ b/include/linux/regulator/driver.h
@@ -264,6 +264,7 @@ enum regulator_type {
* @continuous_voltage_range: Indicates if the regulator can set any
* voltage within constrains range.
* @n_voltages: Number of selectors available for ops.list_voltage().
+ * @n_current_limits: Number of selectors available for current limits
*
* @min_uV: Voltage given by the lowest selector (if linear mapping)
* @uV_step: Voltage increase with each selector (if linear mapping)
@@ -278,6 +279,7 @@ enum regulator_type {
* @n_linear_ranges: Number of entries in the @linear_ranges (and in
* linear_range_selectors if used) table(s).
* @volt_table: Voltage mapping table (if table based mapping)
+ * @curr_table: Current limit mapping table (if table based mapping)
*
* @vsel_range_reg: Register for range selector when using pickable ranges
* and regulator_regmap_X_voltage_X_pickable functions.
@@ -333,6 +335,7 @@ struct regulator_desc {
int id;
unsigned int continuous_voltage_range:1;
unsigned n_voltages;
+ unsigned int n_current_limits;
const struct regulator_ops *ops;
int irq;
enum regulator_type type;
@@ -351,6 +354,7 @@ struct regulator_desc {
int n_linear_ranges;

const unsigned int *volt_table;
+ const unsigned int *curr_table;

unsigned int vsel_range_reg;
unsigned int vsel_range_mask;
@@ -534,6 +538,9 @@ int regulator_set_pull_down_regmap(struct regulator_dev *rdev);

int regulator_set_active_discharge_regmap(struct regulator_dev *rdev,
bool enable);
+int regulator_set_current_limit_regmap(struct regulator_dev *rdev,
+ int min_uA, int max_uA);
+int regulator_get_current_limit_regmap(struct regulator_dev *rdev);
void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data);

void regulator_lock(struct regulator_dev *rdev);
--
2.17.1