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Guenter Roeck6700ce02014-01-11 10:28:05 -08001Kernel driver ltc2945
2=====================
3
4Supported chips:
5 * Linear Technology LTC2945
6 Prefix: 'ltc2945'
7 Addresses scanned: -
8 Datasheet:
9 http://cds.linear.com/docs/en/datasheet/2945fa.pdf
10
11Author: Guenter Roeck <linux@roeck-us.net>
12
13
14Description
15-----------
16
17The LTC2945 is a rail-to-rail system monitor that measures current, voltage,
18and power consumption.
19
20
21Usage Notes
22-----------
23
24This driver does not probe for LTC2945 devices, since there is no register
25which can be safely used to identify the chip. You will have to instantiate
26the devices explicitly.
27
28Example: the following will load the driver for an LTC2945 at address 0x10
29on I2C bus #1:
30$ modprobe ltc2945
31$ echo ltc2945 0x10 > /sys/bus/i2c/devices/i2c-1/new_device
32
33
34Sysfs entries
35-------------
36
37Voltage readings provided by this driver are reported as obtained from the ADC
38registers. If a set of voltage divider resistors is installed, calculate the
39real voltage by multiplying the reported value with (R1+R2)/R2, where R1 is the
40value of the divider resistor against the measured voltage and R2 is the value
41of the divider resistor against Ground.
42
43Current reading provided by this driver is reported as obtained from the ADC
44Current Sense register. The reported value assumes that a 1 mOhm sense resistor
45is installed. If a different sense resistor is installed, calculate the real
46current by dividing the reported value by the sense resistor value in mOhm.
47
48in1_input VIN voltage (mV). Voltage is measured either at
49 SENSE+ or VDD pin depending on chip configuration.
50in1_min Undervoltage threshold
51in1_max Overvoltage threshold
52in1_lowest Lowest measured voltage
53in1_highest Highest measured voltage
54in1_reset_history Write 1 to reset in1 history
55in1_min_alarm Undervoltage alarm
56in1_max_alarm Overvoltage alarm
57
58in2_input ADIN voltage (mV)
59in2_min Undervoltage threshold
60in2_max Overvoltage threshold
61in2_lowest Lowest measured voltage
62in2_highest Highest measured voltage
63in2_reset_history Write 1 to reset in2 history
64in2_min_alarm Undervoltage alarm
65in2_max_alarm Overvoltage alarm
66
67curr1_input SENSE current (mA)
68curr1_min Undercurrent threshold
69curr1_max Overcurrent threshold
70curr1_lowest Lowest measured current
71curr1_highest Highest measured current
72curr1_reset_history Write 1 to reset curr1 history
73curr1_min_alarm Undercurrent alarm
74curr1_max_alarm Overcurrent alarm
75
76power1_input Power (in uW). Power is calculated based on SENSE+/VDD
77 voltage or ADIN voltage depending on chip configuration.
78power1_min Low lower threshold
79power1_max High power threshold
80power1_input_lowest Historical minimum power use
81power1_input_highest Historical maximum power use
82power1_reset_history Write 1 to reset power1 history
83power1_min_alarm Low power alarm
84power1_max_alarm High power alarm