The LTC2977 regulator does not set the regulator_desc .n_voltages value
which is needed in order to let the regulator core list the regulator
voltage range.
This patch defines a regulator_desc with a voltage range, and uses it
for defining voltage resolution for regulators LTC2972/LTC2974/LTC2975/
LTC2977/LTC2978/LTC2979/LTC2980/LTM2987 based on that they all have a 16
bit ADC with the same stepwise 122.07uV resolution. It also scales the
resolution to a 1mV resolution which is easier to handle.
Signed-off-by: Mårten Lindahl <marten.lindahl@xxxxxxxx>
---
drivers/hwmon/pmbus/ltc2978.c | 44 +++++++++++++++++++++++++++++++----
drivers/hwmon/pmbus/pmbus.h | 8 +++++--
2 files changed, 46 insertions(+), 6 deletions(-)
diff --git a/drivers/hwmon/pmbus/ltc2978.c b/drivers/hwmon/pmbus/ltc2978.c
index 531aa674a928..6d2592731ba3 100644
--- a/drivers/hwmon/pmbus/ltc2978.c
+++ b/drivers/hwmon/pmbus/ltc2978.c
@@ -562,7 +562,24 @@ static const struct i2c_device_id ltc2978_id[] = {
MODULE_DEVICE_TABLE(i2c, ltc2978_id);
#if IS_ENABLED(CONFIG_SENSORS_LTC2978_REGULATOR)
+#define LTC2978_ADC_RES 0xFFFF
+#define LTC2978_N_ADC 122
+#define LTC2978_MAX_UV (LTC2978_ADC_RES * LTC2978_N_ADC)
+#define LTC2978_UV_STEP 1000
+#define LTC2978_N_VOLTAGES ((LTC2978_MAX_UV / LTC2978_UV_STEP) + 1)
+
static const struct regulator_desc ltc2978_reg_desc[] = {
+ PMBUS_REGULATOR_STEP("vout", 0, LTC2978_N_VOLTAGES, LTC2978_UV_STEP),
+ PMBUS_REGULATOR_STEP("vout", 1, LTC2978_N_VOLTAGES, LTC2978_UV_STEP),
+ PMBUS_REGULATOR_STEP("vout", 2, LTC2978_N_VOLTAGES, LTC2978_UV_STEP),
+ PMBUS_REGULATOR_STEP("vout", 3, LTC2978_N_VOLTAGES, LTC2978_UV_STEP),
+ PMBUS_REGULATOR_STEP("vout", 4, LTC2978_N_VOLTAGES, LTC2978_UV_STEP),
+ PMBUS_REGULATOR_STEP("vout", 5, LTC2978_N_VOLTAGES, LTC2978_UV_STEP),
+ PMBUS_REGULATOR_STEP("vout", 6, LTC2978_N_VOLTAGES, LTC2978_UV_STEP),
+ PMBUS_REGULATOR_STEP("vout", 7, LTC2978_N_VOLTAGES, LTC2978_UV_STEP),
+};
+
+static const struct regulator_desc ltc2978_reg_desc_default[] = {
PMBUS_REGULATOR("vout", 0),
PMBUS_REGULATOR("vout", 1),
PMBUS_REGULATOR("vout", 2),
@@ -839,10 +856,29 @@ static int ltc2978_probe(struct i2c_client *client)
#if IS_ENABLED(CONFIG_SENSORS_LTC2978_REGULATOR)
info->num_regulators = info->pages;
- info->reg_desc = ltc2978_reg_desc;
- if (info->num_regulators > ARRAY_SIZE(ltc2978_reg_desc)) {
- dev_err(&client->dev, "num_regulators too large!");
- info->num_regulators = ARRAY_SIZE(ltc2978_reg_desc);
+ switch (data->id) {
+ case ltc2972:
+ case ltc2974:
+ case ltc2975:
+ case ltc2977:
+ case ltc2978:
+ case ltc2979:
+ case ltc2980:
+ case ltm2987:
+ info->reg_desc = ltc2978_reg_desc;
+ if (info->num_regulators > ARRAY_SIZE(ltc2978_reg_desc)) {
+ dev_warn(&client->dev, "num_regulators too large!");
+ info->num_regulators = ARRAY_SIZE(ltc2978_reg_desc);
+ }
+ break;
+ default:
+ info->reg_desc = ltc2978_reg_desc_default;
+ if (info->num_regulators > ARRAY_SIZE(ltc2978_reg_desc_default)) {
+ dev_warn(&client->dev, "num_regulators too large!");
+ info->num_regulators =
+ ARRAY_SIZE(ltc2978_reg_desc_default);
+ }
+ break;
}
#endif
diff --git a/drivers/hwmon/pmbus/pmbus.h b/drivers/hwmon/pmbus/pmbus.h
index c031a9700ace..4a4689c4ab7f 100644
--- a/drivers/hwmon/pmbus/pmbus.h
+++ b/drivers/hwmon/pmbus/pmbus.h
@@ -463,8 +463,8 @@ struct pmbus_driver_info {
extern const struct regulator_ops pmbus_regulator_ops;
-/* Macro for filling in array of struct regulator_desc */
-#define PMBUS_REGULATOR(_name, _id) \
+/* Macros for filling in array of struct regulator_desc */
+#define PMBUS_REGULATOR_STEP(_name, _id, _voltages, _step) \
[_id] = { \
.name = (_name # _id), \
.supply_name = "vin", \
@@ -474,8 +474,12 @@ extern const struct regulator_ops pmbus_regulator_ops;
.ops = &pmbus_regulator_ops, \
.type = REGULATOR_VOLTAGE, \
.owner = THIS_MODULE, \
+ .n_voltages = _voltages, \
+ .uV_step = _step, \
}
+#define PMBUS_REGULATOR(_name, _id) PMBUS_REGULATOR_STEP(_name, _id, 0, 0)
+
/* Function declarations */
void pmbus_clear_cache(struct i2c_client *client);
--
2.30.2
