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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: | |
7f15b664 M |
17 | * Maxim MAX1617 |
18 | Prefix: 'max1617' | |
19 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | |
20 | Datasheet: Publicly available at the Maxim website | |
21 | * Maxim MAX1617A | |
22 | Prefix: 'max1617a' | |
23 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | |
24 | Datasheet: Publicly available at the Maxim website | |
25 | * National Semiconductor LM84 | |
26 | Prefix: 'lm84' | |
27 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | |
28 | Datasheet: Publicly available at the National Semiconductor website | |
29 | * Philips NE1617 | |
30 | Prefix: 'max1617' (probably detected as a max1617) | |
31 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | |
32 | Datasheet: Publicly available at the Philips website | |
33 | * Philips NE1617A | |
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 | * TI THMC10 | |
38 | Prefix: 'thmc10' | |
39 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | |
40 | Datasheet: Publicly available at the TI website | |
41 | * Onsemi MC1066 | |
42 | Prefix: 'mc1066' | |
43 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | |
44 | Datasheet: Publicly available at the Onsemi website | |
45 | ||
46 | ||
47 | Authors: | |
48 | Frodo Looijaard <frodol@dds.nl>, | |
49 | Philip Edelbrock <phil@netroedge.com> | |
50 | ||
51 | Module Parameters | |
52 | ----------------- | |
53 | ||
54 | * read_only: int | |
55 | Don't set any values, read only mode | |
56 | ||
57 | ||
58 | Description | |
59 | ----------- | |
60 | ||
61 | The chips supported by this driver are very similar. The Maxim MAX1617 is | |
62 | the oldest; it has the problem that it is not very well detectable. The | |
63 | MAX1617A solves that. The ADM1021 is a straight clone of the MAX1617A. | |
64 | Ditto for the THMC10. From here on, we will refer to all these chips as | |
65 | ADM1021-clones. | |
66 | ||
67 | The ADM1021 and MAX1617A reports a die code, which is a sort of revision | |
68 | code. This can help us pinpoint problems; it is not very useful | |
69 | otherwise. | |
70 | ||
71 | ADM1021-clones implement two temperature sensors. One of them is internal, | |
72 | and measures the temperature of the chip itself; the other is external and | |
73 | is realised in the form of a transistor-like device. A special alarm | |
74 | indicates whether the remote sensor is connected. | |
75 | ||
76 | Each sensor has its own low and high limits. When they are crossed, the | |
77 | corresponding alarm is set and remains on as long as the temperature stays | |
78 | out of range. Temperatures are measured in degrees Celsius. Measurements | |
79 | are possible between -65 and +127 degrees, with a resolution of one degree. | |
80 | ||
81 | If an alarm triggers, it will remain triggered until the hardware register | |
82 | is read at least once. This means that the cause for the alarm may already | |
83 | have disappeared! | |
84 | ||
85 | This driver only updates its values each 1.5 seconds; reading it more often | |
86 | will do no harm, but will return 'old' values. It is possible to make | |
87 | ADM1021-clones do faster measurements, but there is really no good reason | |
88 | for that. | |
89 | ||
7f15b664 | 90 | |
d7ce0335 JD |
91 | Netburst-based Xeon support |
92 | --------------------------- | |
7f15b664 | 93 | |
d7ce0335 JD |
94 | Some Xeon processors based on the Netburst (early Pentium 4, from 2001 to |
95 | 2003) microarchitecture had real MAX1617, ADM1021, or compatible chips | |
96 | within them, with two temperature sensors. Other Xeon processors of this | |
97 | era (with 400 MHz FSB) had chips with only one temperature sensor. | |
7f15b664 | 98 | |
d7ce0335 JD |
99 | If you have such an old Xeon, and you get two valid temperatures when |
100 | loading the adm1021 module, then things are good. | |
7f15b664 | 101 | |
d7ce0335 JD |
102 | If nothing happens when loading the adm1021 module, and you are certain |
103 | that your specific Xeon processor model includes compatible sensors, you | |
104 | will have to explicitly instantiate the sensor chips from user-space. See | |
105 | method 4 in Documentation/i2c/instantiating-devices. Possible slave | |
106 | addresses are 0x18, 0x1a, 0x29, 0x2b, 0x4c, or 0x4e. It is likely that | |
107 | only temp2 will be correct and temp1 will have to be ignored. | |
7f15b664 | 108 | |
d7ce0335 JD |
109 | Previous generations of the Xeon processor (based on Pentium II/III) |
110 | didn't have these sensors. Next generations of Xeon processors (533 MHz | |
111 | FSB and faster) lost them, until the Core-based generation which | |
112 | introduced integrated digital thermal sensors. These are supported by | |
113 | the coretemp driver. |