hwmon: (ina238) Add support for INA780

INA780 is similar to the other chips in the series, but does not
support the shunt voltage register. Shunt voltage limit registers
have been renamed to current limit registers, but are otherwise
identical.

While the chip does not directly report the shunt voltage, report
it anyway by calculating its value from the current register.

Cc: Chris Packham <chris.packham@alliedtelesis.co.nz>
Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Tested-by: Chris Packham <chris.packham@alliedtelesis.co.nz> # INA780
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

3 files changed, 28 insertions, 5 deletions

diff --git a/Documentation/hwmon/ina238.rst b/Documentation/hwmon/ina238.rst
index 3c7db4a47056..722760961821 100644
--- a/Documentation/hwmon/ina238.rst
+++ b/Documentation/hwmon/ina238.rst
@@ -32,6 +32,11 @@ Supported chips:
     Datasheet:
 	https://www.ti.com/lit/gpn/ina238
 
+  * Texas Instruments INA780
+
+    Datasheet:
+	https://www.ti.com/product/ina780a
+
   * Silergy SQ52206
 
     Prefix: 'SQ52206'
@@ -56,6 +61,9 @@ INA237 is a functionally equivalent variant of INA238 with slightly
 different accuracy. INA228 is another variant of INA238 with higher ADC
 resolution. This chip also reports the energy.
 
+INA780 is a variant of the chip series with built-in shunt resistor.
+It also reports the energy.
+
 SQ52206 is a mostly compatible chip from Sylergy. It reports the energy
 as well as the peak power consumption.
 
@@ -88,7 +96,7 @@ curr1_max		Maximum current threshold (mA)
 curr1_max_alarm		Maximum current alarm
 
 energy1_input		Energy measurement (uJ)
-				(SQ52206 and INA237 only)
+				(SQ52206, INA237, and INA780 only)
 
 temp1_input		Die temperature measurement (mC)
 temp1_max		Maximum die temperature threshold (mC)
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 6bdce991f5f0..c044c26fbd11 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -2256,9 +2256,9 @@ config SENSORS_INA238
 	depends on I2C
 	select REGMAP_I2C
 	help
-	  If you say yes here you get support for INA228, INA237, INA238, and
-	  SQ52206 power monitor chips. This driver supports voltage, current,
-	  power, energy, and temperature measurements as well as alarm
+	  If you say yes here you get support for INA228, INA237, INA238,
+	  INA780, and SQ52206 power monitor chips. This driver supports voltage,
+	  current, power, energy, and temperature measurements as well as alarm
 	  configuration.
 
 	  This driver can also be built as a module. If so, the module
diff --git a/drivers/hwmon/ina238.c b/drivers/hwmon/ina238.c
index da5b43184dd1..98255619adeb 100644
--- a/drivers/hwmon/ina238.c
+++ b/drivers/hwmon/ina238.c
@@ -101,7 +101,7 @@ static const struct regmap_config ina238_regmap_config = {
 	.val_bits = 16,
 };
 
-enum ina238_ids { ina228, ina237, ina238, sq52206 };
+enum ina238_ids { ina228, ina237, ina238, ina780, sq52206 };
 
 struct ina238_config {
 	bool has_20bit_voltage_current; /* vshunt, vbus and current are 20-bit fields */
@@ -155,6 +155,16 @@ static const struct ina238_config ina238_config[] = {
 		.bus_voltage_lsb = INA238_BUS_VOLTAGE_LSB,
 		.temp_resolution = 12,
 	},
+	[ina780] = {
+		.has_20bit_voltage_current = false,
+		.has_energy = true,
+		.has_power_highest = false,
+		.power_calculate_factor = 20,
+		.config_default = INA238_CONFIG_DEFAULT,
+		.bus_voltage_lsb = INA238_BUS_VOLTAGE_LSB,
+		.temp_resolution = 12,
+		.current_lsb = 2400,
+	},
 	[sq52206] = {
 		.has_20bit_voltage_current = false,
 		.has_energy = true,
@@ -836,6 +846,7 @@ static const struct i2c_device_id ina238_id[] = {
 	{ "ina228", ina228 },
 	{ "ina237", ina237 },
 	{ "ina238", ina238 },
+	{ "ina780", ina780 },
 	{ "sq52206", sq52206 },
 	{ }
 };
@@ -855,6 +866,10 @@ static const struct of_device_id __maybe_unused ina238_of_match[] = {
 		.data = (void *)ina238
 	},
 	{
+		.compatible = "ti,ina780",
+		.data = (void *)ina780
+	},
+	{
 		.compatible = "silergy,sq52206",
 		.data = (void *)sq52206
 	},