xref: /linux/Documentation/hwmon/ltc4260.rst (revision b77e0ce62d63a761ffb7f7245a215a49f5921c2f)
1Kernel driver ltc4260
2=====================
3
4Supported chips:
5
6  * Linear Technology LTC4260
7
8    Prefix: 'ltc4260'
9
10    Addresses scanned: -
11
12    Datasheet:
13
14	http://cds.linear.com/docs/en/datasheet/4260fc.pdf
15
16Author: Guenter Roeck <linux@roeck-us.net>
17
18
19Description
20-----------
21
22The LTC4260 Hot Swap controller allows a board to be safely inserted
23and removed from a live backplane.
24
25
26Usage Notes
27-----------
28
29This driver does not probe for LTC4260 devices, since there is no register
30which can be safely used to identify the chip. You will have to instantiate
31the devices explicitly.
32
33Example: the following will load the driver for an LTC4260 at address 0x10
34on I2C bus #1::
35
36	$ modprobe ltc4260
37	$ echo ltc4260 0x10 > /sys/bus/i2c/devices/i2c-1/new_device
38
39
40Sysfs entries
41-------------
42
43Voltage readings provided by this driver are reported as obtained from the ADC
44registers. If a set of voltage divider resistors is installed, calculate the
45real voltage by multiplying the reported value with (R1+R2)/R2, where R1 is the
46value of the divider resistor against the measured voltage and R2 is the value
47of the divider resistor against Ground.
48
49Current reading provided by this driver is reported as obtained from the ADC
50Current Sense register. The reported value assumes that a 1 mOhm sense resistor
51is installed. If a different sense resistor is installed, calculate the real
52current by dividing the reported value by the sense resistor value in mOhm.
53
54======================= =======================
55in1_input		SOURCE voltage (mV)
56in1_min_alarm		Undervoltage alarm
57in1_max_alarm		Overvoltage alarm
58
59in2_input		ADIN voltage (mV)
60in2_alarm		Power bad alarm
61
62curr1_input		SENSE current (mA)
63curr1_alarm		SENSE overcurrent alarm
64======================= =======================
65