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Hartmut Rick59ac8362006-03-23 16:37:23 +01001Kernel driver smsc47m192
2========================
3
4Supported chips:
5 * SMSC LPC47M192 and LPC47M997
6 Prefix: 'smsc47m192'
7 Addresses scanned: I2C 0x2c - 0x2d
8 Datasheet: The datasheet for LPC47M192 is publicly available from
9 http://www.smsc.com/
10 The LPC47M997 is compatible for hardware monitoring.
11
12Author: Hartmut Rick <linux@rick.claranet.de>
13 Special thanks to Jean Delvare for careful checking
14 of the code and many helpful comments and suggestions.
15
16
17Description
18-----------
19
20This driver implements support for the hardware sensor capabilities
21of the SMSC LPC47M192 and LPC47M997 Super-I/O chips.
22
23These chips support 3 temperature channels and 8 voltage inputs
24as well as CPU voltage VID input.
25
26They do also have fan monitoring and control capabilities, but the
27these features are accessed via ISA bus and are not supported by this
28driver. Use the 'smsc47m1' driver for fan monitoring and control.
29
30Voltages and temperatures are measured by an 8-bit ADC, the resolution
31of the temperatures is 1 bit per degree C.
32Voltages are scaled such that the nominal voltage corresponds to
33192 counts, i.e. 3/4 of the full range. Thus the available range for
34each voltage channel is 0V ... 255/192*(nominal voltage), the resolution
35is 1 bit per (nominal voltage)/192.
36Both voltage and temperature values are scaled by 1000, the sys files
37show voltages in mV and temperatures in units of 0.001 degC.
38
39The +12V analog voltage input channel (in4_input) is multiplexed with
40bit 4 of the encoded CPU voltage. This means that you either get
41a +12V voltage measurement or a 5 bit CPU VID, but not both.
42The default setting is to use the pin as 12V input, and use only 4 bit VID.
43This driver assumes that the information in the configuration register
44is correct, i.e. that the BIOS has updated the configuration if
45the motherboard has this input wired to VID4.
46
47The temperature and voltage readings are updated once every 1.5 seconds.
48Reading them more often repeats the same values.
49
50
51sysfs interface
52---------------
53
54in0_input - +2.5V voltage input
55in1_input - CPU voltage input (nominal 2.25V)
56in2_input - +3.3V voltage input
57in3_input - +5V voltage input
58in4_input - +12V voltage input (may be missing if used as VID4)
59in5_input - Vcc voltage input (nominal 3.3V)
60 This is the supply voltage of the sensor chip itself.
61in6_input - +1.5V voltage input
62in7_input - +1.8V voltage input
63
64in[0-7]_min,
65in[0-7]_max - lower and upper alarm thresholds for in[0-7]_input reading
66
67 All voltages are read and written in mV.
68
69in[0-7]_alarm - alarm flags for voltage inputs
70 These files read '1' in case of alarm, '0' otherwise.
71
72temp1_input - chip temperature measured by on-chip diode
73temp[2-3]_input - temperature measured by external diodes (one of these would
74 typically be wired to the diode inside the CPU)
75
76temp[1-3]_min,
77temp[1-3]_max - lower and upper alarm thresholds for temperatures
78
79temp[1-3]_offset - temperature offset registers
80 The chip adds the offsets stored in these registers to
81 the corresponding temperature readings.
82 Note that temp1 and temp2 offsets share the same register,
83 they cannot both be different from zero at the same time.
84 Writing a non-zero number to one of them will reset the other
85 offset to zero.
86
87 All temperatures and offsets are read and written in
88 units of 0.001 degC.
89
90temp[1-3]_alarm - alarm flags for temperature inputs, '1' in case of alarm,
91 '0' otherwise.
92temp[2-3]_input_fault - diode fault flags for temperature inputs 2 and 3.
93 A fault is detected if the two pins for the corresponding
94 sensor are open or shorted, or any of the two is shorted
95 to ground or Vcc. '1' indicates a diode fault.
96
97cpu0_vid - CPU voltage as received from the CPU
98
99vrm - CPU VID standard used for decoding CPU voltage
100
101 The *_min, *_max, *_offset and vrm files can be read and
102 written, all others are read-only.