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+Kernel driver ina2xx
+====================
+
+Supported chips:
+
+ * Texas Instruments INA219
+
+
+ Prefix: 'ina219'
+ Addresses: I2C 0x40 - 0x4f
+
+ Datasheet: Publicly available at the Texas Instruments website
+
+ https://www.ti.com/
+
+ * Texas Instruments INA220
+
+ Prefix: 'ina220'
+
+ Addresses: I2C 0x40 - 0x4f
+
+ Datasheet: Publicly available at the Texas Instruments website
+
+ https://www.ti.com/
+
+ * Texas Instruments INA226
+
+ Prefix: 'ina226'
+
+ Addresses: I2C 0x40 - 0x4f
+
+ Datasheet: Publicly available at the Texas Instruments website
+
+ https://www.ti.com/
+
+ * Texas Instruments INA230
+
+ Prefix: 'ina230'
+
+ Addresses: I2C 0x40 - 0x4f
+
+ Datasheet: Publicly available at the Texas Instruments website
+
+ https://www.ti.com/
+
+ * Texas Instruments INA231
+
+ Prefix: 'ina231'
+
+ Addresses: I2C 0x40 - 0x4f
+
+ Datasheet: Publicly available at the Texas Instruments website
+
+ https://www.ti.com/
+
+Author: Lothar Felten <lothar.felten@gmail.com>
+
+Description
+-----------
+
+The INA219 is a high-side current shunt and power monitor with an I2C
+interface. The INA219 monitors both shunt drop and supply voltage, with
+programmable conversion times and filtering.
+
+The INA220 is a high or low side current shunt and power monitor with an I2C
+interface. The INA220 monitors both shunt drop and supply voltage.
+
+The INA226 is a current shunt and power monitor with an I2C interface.
+The INA226 monitors both a shunt voltage drop and bus supply voltage.
+
+INA230 and INA231 are high or low side current shunt and power monitors
+with an I2C interface. The chips monitor both a shunt voltage drop and
+bus supply voltage.
+
+The shunt value in micro-ohms can be set via platform data or device tree at
+compile-time or via the shunt_resistor attribute in sysfs at run-time. Please
+refer to the Documentation/devicetree/bindings/hwmon/ina2xx.txt for bindings
+if the device tree is used.
+
+Additionally ina226 supports update_interval attribute as described in
+Documentation/hwmon/sysfs-interface.rst. Internally the interval is the sum of
+bus and shunt voltage conversion times multiplied by the averaging rate. We
+don't touch the conversion times and only modify the number of averages. The
+lower limit of the update_interval is 2 ms, the upper limit is 2253 ms.
+The actual programmed interval may vary from the desired value.
+
+General sysfs entries
+---------------------
+
+======================= ===============================
+in0_input Shunt voltage(mV) channel
+in1_input Bus voltage(mV) channel
+curr1_input Current(mA) measurement channel
+power1_input Power(uW) measurement channel
+shunt_resistor Shunt resistance(uOhm) channel
+======================= ===============================
+
+Sysfs entries for ina226, ina230 and ina231 only
+------------------------------------------------
+
+======================= ====================================================
+in0_lcrit Critical low shunt voltage
+in0_crit Critical high shunt voltage
+in0_lcrit_alarm Shunt voltage critical low alarm
+in0_crit_alarm Shunt voltage critical high alarm
+in1_lcrit Critical low bus voltage
+in1_crit Critical high bus voltage
+in1_lcrit_alarm Bus voltage critical low alarm
+in1_crit_alarm Bus voltage critical high alarm
+power1_crit Critical high power
+power1_crit_alarm Power critical high alarm
+update_interval data conversion time; affects number of samples used
+ to average results for shunt and bus voltages.
+======================= ====================================================
+
+.. note::
+
+ - Configure `shunt_resistor` before configure `power1_crit`, because power
+ value is calculated based on `shunt_resistor` set.
+ - Because of the underlying register implementation, only one `*crit` setting
+ and its `alarm` can be active. Writing to one `*crit` setting clears other
+ `*crit` settings and alarms. Writing 0 to any `*crit` setting clears all
+ `*crit` settings and alarms.