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

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	  * 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	
90	
91	Netburst-based Xeon support
92	---------------------------
93	
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.
98	
99	If you have such an old Xeon, and you get two valid temperatures when
100	loading the adm1021 module, then things are good.
101	
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.
108	
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.
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