hwmon: Driver for Texas Instruments INA209

Add support for the TI / Burr-Brown INA209 voltage / current / power
monitor.

Cc: Paul Hays <haysp@magma.net>
Cc: Ira W. Snyder <iws@ovro.caltech.edu>
Tested-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Documentation/devicetree/bindings/i2c/ina209.txt

+ina209 properties
+
+Required properties:
+- compatible: Must be "ti,ina209"
+- reg: I2C address
+
+Optional properties:
+
+- shunt-resistor
+	Shunt resistor value in micro-Ohm
+
+Example:
+
+temp-sensor@4c {
+	compatible = "ti,ina209";
+	reg = <0x4c>;
+	shunt-resistor = <5000>;
+};

Documentation/hwmon/ina209

+Kernel driver ina209
+=====================
+
+Supported chips:
+  * Burr-Brown / Texas Instruments INA209
+    Prefix: 'ina209'
+    Addresses scanned: -
+    Datasheet:
+        http://www.ti.com/lit/gpn/ina209
+
+Author: Paul Hays <Paul.Hays@cattail.ca>
+Author: Ira W. Snyder <iws@ovro.caltech.edu>
+Author: Guenter Roeck <linux@roeck-us.net>
+
+
+Description
+-----------
+
+The TI / Burr-Brown INA209 monitors voltage, current, and power on the high side
+of a D.C. power supply. It can perform measurements and calculations in the
+background to supply readings at any time. It includes a programmable
+calibration multiplier to scale the displayed current and power values.
+
+
+Sysfs entries
+-------------
+
+The INA209 chip is highly configurable both via hardwiring and via
+the I2C bus. See the datasheet for details.
+
+This tries to expose most monitoring features of the hardware via
+sysfs. It does not support every feature of this chip.
+
+
+in0_input		shunt voltage (mV)
+in0_input_highest	shunt voltage historical maximum reading (mV)
+in0_input_lowest	shunt voltage historical minimum reading (mV)
+in0_reset_history	reset shunt voltage history
+in0_max			shunt voltage max alarm limit (mV)
+in0_min			shunt voltage min alarm limit (mV)
+in0_crit_max		shunt voltage crit max alarm limit (mV)
+in0_crit_min		shunt voltage crit min alarm limit (mV)
+in0_max_alarm		shunt voltage max alarm limit exceeded
+in0_min_alarm		shunt voltage min alarm limit exceeded
+in0_crit_max_alarm	shunt voltage crit max alarm limit exceeded
+in0_crit_min_alarm	shunt voltage crit min alarm limit exceeded
+
+in1_input		bus voltage (mV)
+in1_input_highest	bus voltage historical maximum reading (mV)
+in1_input_lowest	bus voltage historical minimum reading (mV)
+in1_reset_history	reset bus voltage history
+in1_max			bus voltage max alarm limit (mV)
+in1_min			bus voltage min alarm limit (mV)
+in1_crit_max		bus voltage crit max alarm limit (mV)
+in1_crit_min		bus voltage crit min alarm limit (mV)
+in1_max_alarm		bus voltage max alarm limit exceeded
+in1_min_alarm		bus voltage min alarm limit exceeded
+in1_crit_max_alarm	bus voltage crit max alarm limit exceeded
+in1_crit_min_alarm	bus voltage crit min alarm limit exceeded
+
+power1_input		power measurement (uW)
+power1_input_highest	power historical maximum reading (uW)
+power1_reset_history	reset power history
+power1_max		power max alarm limit (uW)
+power1_crit		power crit alarm limit (uW)
+power1_max_alarm	power max alarm limit exceeded
+power1_crit_alarm	power crit alarm limit exceeded
+
+curr1_input		current measurement (mA)
+
+update_interval		data conversion time; affects number of samples used
+			to average results for shunt and bus voltages.
+
+General Remarks
+---------------
+
+The power and current registers in this chip require that the calibration
+register is programmed correctly before they are used. Normally this is expected
+to be done in the BIOS. In the absence of BIOS programming, the shunt resistor
+voltage can be provided using platform data. The driver uses platform data from
+the ina2xx driver for this purpose. If calibration register data is not provided
+via platform data, the driver checks if the calibration register has been
+programmed (ie has a value not equal to zero). If so, this value is retained.
+Otherwise, a default value reflecting a shunt resistor value of 10 mOhm is
+programmed into the calibration register.
+
+
+Output Pins
+-----------
+
+Output pin programming is a board feature which depends on the BIOS. It is
+outside the scope of a hardware monitoring driver to enable or disable output
+pins.

drivers/hwmon/Kconfig

@@ -1157,6 +1157,16 @@ config SENSORS_AMC6821
 	  This driver can also be build as a module.  If so, the module
 	  will be called amc6821.
 
+config SENSORS_INA209
+	tristate "TI / Burr Brown INA209"
+	depends on I2C
+	help
+	  If you say yes here you get support for the TI / Burr Brown INA209
+	  voltage / current / power monitor I2C interface.
+
+	  This driver can also be built as a module. If so, the module will
+	  be called ina209.
+
 config SENSORS_INA2XX
 	tristate "Texas Instruments INA219 and compatibles"
 	depends on I2C

drivers/hwmon/Makefile

@@ -65,6 +65,7 @@ obj-$(CONFIG_SENSORS_ULTRA45)	+= ultra45_env.o
 obj-$(CONFIG_SENSORS_I5K_AMB)	+= i5k_amb.o
 obj-$(CONFIG_SENSORS_IBMAEM)	+= ibmaem.o
 obj-$(CONFIG_SENSORS_IBMPEX)	+= ibmpex.o
+obj-$(CONFIG_SENSORS_INA209)	+= ina209.o
 obj-$(CONFIG_SENSORS_INA2XX)	+= ina2xx.o
 obj-$(CONFIG_SENSORS_IT87)	+= it87.o
 obj-$(CONFIG_SENSORS_JC42)	+= jc42.o