xref: /linux/Documentation/hwmon/asb100.rst (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1Kernel driver asb100
2====================
3
4Supported Chips:
5
6  * Asus ASB100 and ASB100-A "Bach"
7
8    Prefix: 'asb100'
9
10    Addresses scanned: I2C 0x2d
11
12    Datasheet: none released
13
14Author: Mark M. Hoffman <mhoffman@lightlink.com>
15
16Description
17-----------
18
19This driver implements support for the Asus ASB100 and ASB100-A "Bach".
20These are custom ASICs available only on Asus mainboards. Asus refuses to
21supply a datasheet for these chips. Thanks go to many people who helped
22investigate their hardware, including:
23
24Vitaly V. Bursov
25Alexander van Kaam (author of MBM for Windows)
26Bertrik Sikken
27
28The ASB100 implements seven voltage sensors, three fan rotation speed
29sensors, four temperature sensors, VID lines and alarms. In addition to
30these, the ASB100-A also implements a single PWM controller for fans 2 and
313 (i.e. one setting controls both.) If you have a plain ASB100, the PWM
32controller will simply not work (or maybe it will for you... it doesn't for
33me).
34
35Temperatures are measured and reported in degrees Celsius.
36
37Fan speeds are reported in RPM (rotations per minute). An alarm is
38triggered if the rotation speed has dropped below a programmable limit.
39
40Voltage sensors (also known as IN sensors) report values in volts.
41
42The VID lines encode the core voltage value: the voltage level your
43processor should work with. This is hardcoded by the mainboard and/or
44processor itself. It is a value in volts.
45
46Alarms: (TODO question marks indicate may or may not work)
47
48- 0x0001 => in0 (?)
49- 0x0002 => in1 (?)
50- 0x0004 => in2
51- 0x0008 => in3
52- 0x0010 => temp1 [1]_
53- 0x0020 => temp2
54- 0x0040 => fan1
55- 0x0080 => fan2
56- 0x0100 => in4
57- 0x0200 => in5 (?) [2]_
58- 0x0400 => in6 (?) [2]_
59- 0x0800 => fan3
60- 0x1000 => chassis switch
61- 0x2000 => temp3
62
63.. [1]	This alarm will only trigger if the hysteresis value is 127C.
64	I.e. it behaves the same as w83781d.
65
66.. [2]	The min and max registers for these values appear to
67	be read-only or otherwise stuck at 0x00.
68
69TODO:
70  * Experiment with fan divisors > 8.
71  * Experiment with temp. sensor types.
72  * Are there really 13 voltage inputs? Probably not...
73  * Cleanups, no doubt...
74