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Based on kernel version 3.15.4. Page generated on 2014-07-07 09:03 EST.

1	Kernel driver ltc4245
2	=====================
3	
4	Supported chips:
5	  * Linear Technology LTC4245
6	    Prefix: 'ltc4245'
7	    Addresses scanned: 0x20-0x3f
8	    Datasheet:
9	        http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1006,C1140,P19392,D13517
10	
11	Author: Ira W. Snyder <iws@ovro.caltech.edu>
12	
13	
14	Description
15	-----------
16	
17	The LTC4245 controller allows a board to be safely inserted and removed
18	from a live backplane in multiple supply systems such as CompactPCI and
19	PCI Express.
20	
21	
22	Usage Notes
23	-----------
24	
25	This driver does not probe for LTC4245 devices, due to the fact that some
26	of the possible addresses are unfriendly to probing. You will have to
27	instantiate the devices explicitly.
28	
29	Example: the following will load the driver for an LTC4245 at address 0x23
30	on I2C bus #1:
31	$ modprobe ltc4245
32	$ echo ltc4245 0x23 > /sys/bus/i2c/devices/i2c-1/new_device
33	
34	
35	Sysfs entries
36	-------------
37	
38	The LTC4245 has built-in limits for over and under current warnings. This
39	makes it very likely that the reference circuit will be used.
40	
41	This driver uses the values in the datasheet to change the register values
42	into the values specified in the sysfs-interface document. The current readings
43	rely on the sense resistors listed in Table 2: "Sense Resistor Values".
44	
45	in1_input		12v input voltage (mV)
46	in2_input		5v  input voltage (mV)
47	in3_input		3v  input voltage (mV)
48	in4_input		Vee (-12v) input voltage (mV)
49	
50	in1_min_alarm		12v input undervoltage alarm
51	in2_min_alarm		5v  input undervoltage alarm
52	in3_min_alarm		3v  input undervoltage alarm
53	in4_min_alarm		Vee (-12v) input undervoltage alarm
54	
55	curr1_input		12v current (mA)
56	curr2_input		5v  current (mA)
57	curr3_input		3v  current (mA)
58	curr4_input		Vee (-12v) current (mA)
59	
60	curr1_max_alarm		12v overcurrent alarm
61	curr2_max_alarm		5v  overcurrent alarm
62	curr3_max_alarm		3v  overcurrent alarm
63	curr4_max_alarm		Vee (-12v) overcurrent alarm
64	
65	in5_input		12v output voltage (mV)
66	in6_input		5v  output voltage (mV)
67	in7_input		3v  output voltage (mV)
68	in8_input		Vee (-12v) output voltage (mV)
69	
70	in5_min_alarm		12v output undervoltage alarm
71	in6_min_alarm		5v  output undervoltage alarm
72	in7_min_alarm		3v  output undervoltage alarm
73	in8_min_alarm		Vee (-12v) output undervoltage alarm
74	
75	in9_input		GPIO voltage data (see note 1)
76	in10_input		GPIO voltage data (see note 1)
77	in11_input		GPIO voltage data (see note 1)
78	
79	power1_input		12v power usage (mW)
80	power2_input		5v  power usage (mW)
81	power3_input		3v  power usage (mW)
82	power4_input		Vee (-12v) power usage (mW)
83	
84	
85	Note 1
86	------
87	
88	If you have NOT configured the driver to sample all GPIO pins as analog
89	voltages, then the in10_input and in11_input sysfs attributes will not be
90	created. The driver will sample the GPIO pin that is currently connected to the
91	ADC as an analog voltage, and report the value in in9_input.
92	
93	If you have configured the driver to sample all GPIO pins as analog voltages,
94	then they will be sampled in round-robin fashion. If userspace reads too
95	slowly, -EAGAIN will be returned when you read the sysfs attribute containing
96	the sensor reading.
97	
98	The LTC4245 chip can be configured to sample all GPIO pins with two methods:
99	1) platform data -- see include/linux/i2c/ltc4245.h
100	2) OF device tree -- add the "ltc4245,use-extra-gpios" property to each chip
101	
102	The default mode of operation is to sample a single GPIO pin.
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