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1 | Kernel driver adm1021 | ||
2 | ===================== | ||
3 | |||
4 | Supported chips: | ||
5 | * Analog Devices ADM1021 | ||
6 | Prefix: 'adm1021' | ||
7 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | ||
8 | Datasheet: Publicly available at the Analog Devices website | ||
9 | * Analog Devices ADM1021A/ADM1023 | ||
10 | Prefix: 'adm1023' | ||
11 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | ||
12 | Datasheet: Publicly available at the Analog Devices website | ||
13 | * Genesys Logic GL523SM | ||
14 | Prefix: 'gl523sm' | ||
15 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | ||
16 | Datasheet: | ||
17 | * Intel Xeon Processor | ||
18 | Prefix: - any other - may require 'force_adm1021' parameter | ||
19 | Addresses scanned: none | ||
20 | Datasheet: Publicly available at Intel website | ||
21 | * Maxim MAX1617 | ||
22 | Prefix: 'max1617' | ||
23 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | ||
24 | Datasheet: Publicly available at the Maxim website | ||
25 | * Maxim MAX1617A | ||
26 | Prefix: 'max1617a' | ||
27 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | ||
28 | Datasheet: Publicly available at the Maxim website | ||
29 | * National Semiconductor LM84 | ||
30 | Prefix: 'lm84' | ||
31 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | ||
32 | Datasheet: Publicly available at the National Semiconductor website | ||
33 | * Philips NE1617 | ||
34 | Prefix: 'max1617' (probably detected as a max1617) | ||
35 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | ||
36 | Datasheet: Publicly available at the Philips website | ||
37 | * Philips NE1617A | ||
38 | Prefix: 'max1617' (probably detected as a max1617) | ||
39 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | ||
40 | Datasheet: Publicly available at the Philips website | ||
41 | * TI THMC10 | ||
42 | Prefix: 'thmc10' | ||
43 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | ||
44 | Datasheet: Publicly available at the TI website | ||
45 | * Onsemi MC1066 | ||
46 | Prefix: 'mc1066' | ||
47 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | ||
48 | Datasheet: Publicly available at the Onsemi website | ||
49 | |||
50 | |||
51 | Authors: | ||
52 | Frodo Looijaard <frodol@dds.nl>, | ||
53 | Philip Edelbrock <phil@netroedge.com> | ||
54 | |||
55 | Module Parameters | ||
56 | ----------------- | ||
57 | |||
58 | * read_only: int | ||
59 | Don't set any values, read only mode | ||
60 | |||
61 | |||
62 | Description | ||
63 | ----------- | ||
64 | |||
65 | The chips supported by this driver are very similar. The Maxim MAX1617 is | ||
66 | the oldest; it has the problem that it is not very well detectable. The | ||
67 | MAX1617A solves that. The ADM1021 is a straight clone of the MAX1617A. | ||
68 | Ditto for the THMC10. From here on, we will refer to all these chips as | ||
69 | ADM1021-clones. | ||
70 | |||
71 | The ADM1021 and MAX1617A reports a die code, which is a sort of revision | ||
72 | code. This can help us pinpoint problems; it is not very useful | ||
73 | otherwise. | ||
74 | |||
75 | ADM1021-clones implement two temperature sensors. One of them is internal, | ||
76 | and measures the temperature of the chip itself; the other is external and | ||
77 | is realised in the form of a transistor-like device. A special alarm | ||
78 | indicates whether the remote sensor is connected. | ||
79 | |||
80 | Each sensor has its own low and high limits. When they are crossed, the | ||
81 | corresponding alarm is set and remains on as long as the temperature stays | ||
82 | out of range. Temperatures are measured in degrees Celsius. Measurements | ||
83 | are possible between -65 and +127 degrees, with a resolution of one degree. | ||
84 | |||
85 | If an alarm triggers, it will remain triggered until the hardware register | ||
86 | is read at least once. This means that the cause for the alarm may already | ||
87 | have disappeared! | ||
88 | |||
89 | This driver only updates its values each 1.5 seconds; reading it more often | ||
90 | will do no harm, but will return 'old' values. It is possible to make | ||
91 | ADM1021-clones do faster measurements, but there is really no good reason | ||
92 | for that. | ||
93 | |||
94 | Xeon support | ||
95 | ------------ | ||
96 | |||
97 | Some Xeon processors have real max1617, adm1021, or compatible chips | ||
98 | within them, with two temperature sensors. | ||
99 | |||
100 | Other Xeons have chips with only one sensor. | ||
101 | |||
102 | If you have a Xeon, and the adm1021 module loads, and both temperatures | ||
103 | appear valid, then things are good. | ||
104 | |||
105 | If the adm1021 module doesn't load, you should try this: | ||
106 | modprobe adm1021 force_adm1021=BUS,ADDRESS | ||
107 | ADDRESS can only be 0x18, 0x1a, 0x29, 0x2b, 0x4c, or 0x4e. | ||
108 | |||
109 | If you have dual Xeons you may have appear to have two separate | ||
110 | adm1021-compatible chips, or two single-temperature sensors, at distinct | ||
111 | addresses. | ||