xref: /linux/Documentation/hwmon/ina209.rst (revision 962fad301c33dec69324dc2d9320fd84a119a24c)
1Kernel driver ina209
2====================
3
4Supported chips:
5
6  * Burr-Brown / Texas Instruments INA209
7
8    Prefix: 'ina209'
9
10    Addresses scanned: -
11
12    Datasheet:
13	https://www.ti.com/lit/gpn/ina209
14
15Author:
16	- Paul Hays <Paul.Hays@cattail.ca>
17	- Ira W. Snyder <iws@ovro.caltech.edu>
18	- Guenter Roeck <linux@roeck-us.net>
19
20
21Description
22-----------
23
24The TI / Burr-Brown INA209 monitors voltage, current, and power on the high side
25of a D.C. power supply. It can perform measurements and calculations in the
26background to supply readings at any time. It includes a programmable
27calibration multiplier to scale the displayed current and power values.
28
29
30Sysfs entries
31-------------
32
33The INA209 chip is highly configurable both via hardwiring and via
34the I2C bus. See the datasheet for details.
35
36This tries to expose most monitoring features of the hardware via
37sysfs. It does not support every feature of this chip.
38
39======================= =======================================================
40in0_input		shunt voltage (mV)
41in0_input_highest	shunt voltage historical maximum reading (mV)
42in0_input_lowest	shunt voltage historical minimum reading (mV)
43in0_reset_history	reset shunt voltage history
44in0_max			shunt voltage max alarm limit (mV)
45in0_min			shunt voltage min alarm limit (mV)
46in0_crit_max		shunt voltage crit max alarm limit (mV)
47in0_crit_min		shunt voltage crit min alarm limit (mV)
48in0_max_alarm		shunt voltage max alarm limit exceeded
49in0_min_alarm		shunt voltage min alarm limit exceeded
50in0_crit_max_alarm	shunt voltage crit max alarm limit exceeded
51in0_crit_min_alarm	shunt voltage crit min alarm limit exceeded
52
53in1_input		bus voltage (mV)
54in1_input_highest	bus voltage historical maximum reading (mV)
55in1_input_lowest	bus voltage historical minimum reading (mV)
56in1_reset_history	reset bus voltage history
57in1_max			bus voltage max alarm limit (mV)
58in1_min			bus voltage min alarm limit (mV)
59in1_crit_max		bus voltage crit max alarm limit (mV)
60in1_crit_min		bus voltage crit min alarm limit (mV)
61in1_max_alarm		bus voltage max alarm limit exceeded
62in1_min_alarm		bus voltage min alarm limit exceeded
63in1_crit_max_alarm	bus voltage crit max alarm limit exceeded
64in1_crit_min_alarm	bus voltage crit min alarm limit exceeded
65
66power1_input		power measurement (uW)
67power1_input_highest	power historical maximum reading (uW)
68power1_reset_history	reset power history
69power1_max		power max alarm limit (uW)
70power1_crit		power crit alarm limit (uW)
71power1_max_alarm	power max alarm limit exceeded
72power1_crit_alarm	power crit alarm limit exceeded
73
74curr1_input		current measurement (mA)
75
76update_interval		data conversion time; affects number of samples used
77			to average results for shunt and bus voltages.
78======================= =======================================================
79
80General Remarks
81---------------
82
83The power and current registers in this chip require that the calibration
84register is programmed correctly before they are used. Normally this is expected
85to be done in the BIOS. In the absence of BIOS programming, the shunt resistor
86voltage can be provided using platform data. The driver uses platform data from
87the ina2xx driver for this purpose. If calibration register data is not provided
88via platform data, the driver checks if the calibration register has been
89programmed (ie has a value not equal to zero). If so, this value is retained.
90Otherwise, a default value reflecting a shunt resistor value of 10 mOhm is
91programmed into the calibration register.
92
93
94Output Pins
95-----------
96
97Output pin programming is a board feature which depends on the BIOS. It is
98outside the scope of a hardware monitoring driver to enable or disable output
99pins.
100