hwmon: (ina2xx) Add support for INA260

INA260 is similar to other chips of the series, except it has an internal
shunt resistor. The calibration register is therefore not present. Also,
the current register address was changed, though that does not matter for
the driver since the shunt voltage register (which is now the current
register) value is already used to read the current.

Cc: Loic Guegan <loic.guegan@mailbox.org>
Reviewed-by: Tzung-Bi Shih <tzungbi@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

2 files changed, 41 insertions, 6 deletions

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 08a3c863f80a..6a3385598cc6 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -2167,11 +2167,12 @@ config SENSORS_INA2XX
 	select REGMAP_I2C
 	help
 	  If you say yes here you get support for INA219, INA220, INA226,
-	  INA230, and INA231 power monitor chips.
+	  INA230, INA231, and INA260 power monitor chips.
 
 	  The INA2xx driver is configured for the default configuration of
 	  the part as described in the datasheet.
-	  Default value for Rshunt is 10 mOhms.
+	  Default value for Rshunt is 10 mOhms except for INA260 which has an
+	  internal 2 mOhm shunt resistor.
 	  This driver can also be built as a module. If so, the module
 	  will be called ina2xx.
 
diff --git a/drivers/hwmon/ina2xx.c b/drivers/hwmon/ina2xx.c
index 03a011c9b73d..cecc80a41a97 100644
--- a/drivers/hwmon/ina2xx.c
+++ b/drivers/hwmon/ina2xx.c
@@ -56,12 +56,14 @@
 /* settings - depend on use case */
 #define INA219_CONFIG_DEFAULT		0x399F	/* PGA=8 */
 #define INA226_CONFIG_DEFAULT		0x4527	/* averages=16 */
+#define INA260_CONFIG_DEFAULT		0x6527	/* averages=16 */
 
 /* worst case is 68.10 ms (~14.6Hz, ina219) */
 #define INA2XX_CONVERSION_RATE		15
 #define INA2XX_MAX_DELAY		69 /* worst case delay in ms */
 
 #define INA2XX_RSHUNT_DEFAULT		10000
+#define INA260_RSHUNT			2000
 
 /* bit mask for reading the averaging setting in the configuration register */
 #define INA226_AVG_RD_MASK		GENMASK(11, 9)
@@ -125,11 +127,12 @@ static const struct regmap_config ina2xx_regmap_config = {
 	.writeable_reg = ina2xx_writeable_reg,
 };
 
-enum ina2xx_ids { ina219, ina226 };
+enum ina2xx_ids { ina219, ina226, ina260 };
 
 struct ina2xx_config {
 	u16 config_default;
 	bool has_alerts;	/* chip supports alerts and limits */
+	bool has_ishunt;	/* chip has internal shunt resistor */
 	int calibration_value;
 	int shunt_div;
 	int bus_voltage_shift;
@@ -157,6 +160,7 @@ static const struct ina2xx_config ina2xx_config[] = {
 		.bus_voltage_lsb = 4000,
 		.power_lsb_factor = 20,
 		.has_alerts = false,
+		.has_ishunt = false,
 	},
 	[ina226] = {
 		.config_default = INA226_CONFIG_DEFAULT,
@@ -166,6 +170,16 @@ static const struct ina2xx_config ina2xx_config[] = {
 		.bus_voltage_lsb = 1250,
 		.power_lsb_factor = 25,
 		.has_alerts = true,
+		.has_ishunt = false,
+	},
+	[ina260] = {
+		.config_default = INA260_CONFIG_DEFAULT,
+		.shunt_div = 400,
+		.bus_voltage_shift = 0,
+		.bus_voltage_lsb = 1250,
+		.power_lsb_factor = 8,
+		.has_alerts = true,
+		.has_ishunt = true,
 	},
 };
 
@@ -257,6 +271,15 @@ static int ina2xx_read_init(struct device *dev, int reg, long *val)
 	unsigned int regval;
 	int ret, retry;
 
+	if (data->config->has_ishunt) {
+		/* No calibration needed */
+		ret = regmap_read(regmap, reg, &regval);
+		if (ret < 0)
+			return ret;
+		*val = ina2xx_get_value(data, reg, regval);
+		return 0;
+	}
+
 	for (retry = 5; retry; retry--) {
 		ret = regmap_read(regmap, reg, &regval);
 		if (ret < 0)
@@ -686,7 +709,7 @@ static umode_t ina2xx_is_visible(const void *_data, enum hwmon_sensor_types type
 	case hwmon_chip:
 		switch (attr) {
 		case hwmon_chip_update_interval:
-			if (chip == ina226)
+			if (chip == ina226 || chip == ina260)
 				return 0644;
 			break;
 		default:
@@ -795,7 +818,9 @@ static int ina2xx_init(struct device *dev, struct ina2xx_data *data)
 	u32 shunt;
 	int ret;
 
-	if (device_property_read_u32(dev, "shunt-resistor", &shunt) < 0)
+	if (data->config->has_ishunt)
+		shunt = INA260_RSHUNT;
+	else if (device_property_read_u32(dev, "shunt-resistor", &shunt) < 0)
 		shunt = INA2XX_RSHUNT_DEFAULT;
 
 	ret = ina2xx_set_shunt(data, shunt);
@@ -815,6 +840,9 @@ static int ina2xx_init(struct device *dev, struct ina2xx_data *data)
 						FIELD_PREP(INA226_ALERT_POLARITY, active_high));
 	}
 
+	if (data->config->has_ishunt)
+		return 0;
+
 	/*
 	 * Calibration register is set to the best value, which eliminates
 	 * truncation errors on calculating current register in hardware.
@@ -860,7 +888,8 @@ static int ina2xx_probe(struct i2c_client *client)
 
 	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
 							 data, &ina2xx_chip_info,
-							 ina2xx_groups);
+							 data->config->has_ishunt ?
+								NULL : ina2xx_groups);
 	if (IS_ERR(hwmon_dev))
 		return PTR_ERR(hwmon_dev);
 
@@ -876,6 +905,7 @@ static const struct i2c_device_id ina2xx_id[] = {
 	{ "ina226", ina226 },
 	{ "ina230", ina226 },
 	{ "ina231", ina226 },
+	{ "ina260", ina260 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, ina2xx_id);
@@ -901,6 +931,10 @@ static const struct of_device_id __maybe_unused ina2xx_of_match[] = {
 		.compatible = "ti,ina231",
 		.data = (void *)ina226
 	},
+	{
+		.compatible = "ti,ina260",
+		.data = (void *)ina260
+	},
 	{ },
 };
 MODULE_DEVICE_TABLE(of, ina2xx_of_match);