xref: /openbmc/linux/Documentation/hwmon/asb100.rst (revision c39f2d9db0fd81ea20bb5cce9b3f082ca63753e2)
1*7ebd8b66SMauro Carvalho ChehabKernel driver asb100
2*7ebd8b66SMauro Carvalho Chehab====================
3*7ebd8b66SMauro Carvalho Chehab
4*7ebd8b66SMauro Carvalho ChehabSupported Chips:
5*7ebd8b66SMauro Carvalho Chehab
6*7ebd8b66SMauro Carvalho Chehab  * Asus ASB100 and ASB100-A "Bach"
7*7ebd8b66SMauro Carvalho Chehab
8*7ebd8b66SMauro Carvalho Chehab    Prefix: 'asb100'
9*7ebd8b66SMauro Carvalho Chehab
10*7ebd8b66SMauro Carvalho Chehab    Addresses scanned: I2C 0x2d
11*7ebd8b66SMauro Carvalho Chehab
12*7ebd8b66SMauro Carvalho Chehab    Datasheet: none released
13*7ebd8b66SMauro Carvalho Chehab
14*7ebd8b66SMauro Carvalho ChehabAuthor: Mark M. Hoffman <mhoffman@lightlink.com>
15*7ebd8b66SMauro Carvalho Chehab
16*7ebd8b66SMauro Carvalho ChehabDescription
17*7ebd8b66SMauro Carvalho Chehab-----------
18*7ebd8b66SMauro Carvalho Chehab
19*7ebd8b66SMauro Carvalho ChehabThis driver implements support for the Asus ASB100 and ASB100-A "Bach".
20*7ebd8b66SMauro Carvalho ChehabThese are custom ASICs available only on Asus mainboards. Asus refuses to
21*7ebd8b66SMauro Carvalho Chehabsupply a datasheet for these chips. Thanks go to many people who helped
22*7ebd8b66SMauro Carvalho Chehabinvestigate their hardware, including:
23*7ebd8b66SMauro Carvalho Chehab
24*7ebd8b66SMauro Carvalho ChehabVitaly V. Bursov
25*7ebd8b66SMauro Carvalho ChehabAlexander van Kaam (author of MBM for Windows)
26*7ebd8b66SMauro Carvalho ChehabBertrik Sikken
27*7ebd8b66SMauro Carvalho Chehab
28*7ebd8b66SMauro Carvalho ChehabThe ASB100 implements seven voltage sensors, three fan rotation speed
29*7ebd8b66SMauro Carvalho Chehabsensors, four temperature sensors, VID lines and alarms. In addition to
30*7ebd8b66SMauro Carvalho Chehabthese, the ASB100-A also implements a single PWM controller for fans 2 and
31*7ebd8b66SMauro Carvalho Chehab3 (i.e. one setting controls both.) If you have a plain ASB100, the PWM
32*7ebd8b66SMauro Carvalho Chehabcontroller will simply not work (or maybe it will for you... it doesn't for
33*7ebd8b66SMauro Carvalho Chehabme).
34*7ebd8b66SMauro Carvalho Chehab
35*7ebd8b66SMauro Carvalho ChehabTemperatures are measured and reported in degrees Celsius.
36*7ebd8b66SMauro Carvalho Chehab
37*7ebd8b66SMauro Carvalho ChehabFan speeds are reported in RPM (rotations per minute). An alarm is
38*7ebd8b66SMauro Carvalho Chehabtriggered if the rotation speed has dropped below a programmable limit.
39*7ebd8b66SMauro Carvalho Chehab
40*7ebd8b66SMauro Carvalho ChehabVoltage sensors (also known as IN sensors) report values in volts.
41*7ebd8b66SMauro Carvalho Chehab
42*7ebd8b66SMauro Carvalho ChehabThe VID lines encode the core voltage value: the voltage level your
43*7ebd8b66SMauro Carvalho Chehabprocessor should work with. This is hardcoded by the mainboard and/or
44*7ebd8b66SMauro Carvalho Chehabprocessor itself. It is a value in volts.
45*7ebd8b66SMauro Carvalho Chehab
46*7ebd8b66SMauro Carvalho ChehabAlarms: (TODO question marks indicate may or may not work)
47*7ebd8b66SMauro Carvalho Chehab
48*7ebd8b66SMauro Carvalho Chehab- 0x0001 => in0 (?)
49*7ebd8b66SMauro Carvalho Chehab- 0x0002 => in1 (?)
50*7ebd8b66SMauro Carvalho Chehab- 0x0004 => in2
51*7ebd8b66SMauro Carvalho Chehab- 0x0008 => in3
52*7ebd8b66SMauro Carvalho Chehab- 0x0010 => temp1 [1]_
53*7ebd8b66SMauro Carvalho Chehab- 0x0020 => temp2
54*7ebd8b66SMauro Carvalho Chehab- 0x0040 => fan1
55*7ebd8b66SMauro Carvalho Chehab- 0x0080 => fan2
56*7ebd8b66SMauro Carvalho Chehab- 0x0100 => in4
57*7ebd8b66SMauro Carvalho Chehab- 0x0200 => in5 (?) [2]_
58*7ebd8b66SMauro Carvalho Chehab- 0x0400 => in6 (?) [2]_
59*7ebd8b66SMauro Carvalho Chehab- 0x0800 => fan3
60*7ebd8b66SMauro Carvalho Chehab- 0x1000 => chassis switch
61*7ebd8b66SMauro Carvalho Chehab- 0x2000 => temp3
62*7ebd8b66SMauro Carvalho Chehab
63*7ebd8b66SMauro Carvalho Chehab.. [1]	This alarm will only trigger if the hysteresis value is 127C.
64*7ebd8b66SMauro Carvalho Chehab	I.e. it behaves the same as w83781d.
65*7ebd8b66SMauro Carvalho Chehab
66*7ebd8b66SMauro Carvalho Chehab.. [2]	The min and max registers for these values appear to
67*7ebd8b66SMauro Carvalho Chehab	be read-only or otherwise stuck at 0x00.
68*7ebd8b66SMauro Carvalho Chehab
69*7ebd8b66SMauro Carvalho ChehabTODO:
70*7ebd8b66SMauro Carvalho Chehab  * Experiment with fan divisors > 8.
71*7ebd8b66SMauro Carvalho Chehab  * Experiment with temp. sensor types.
72*7ebd8b66SMauro Carvalho Chehab  * Are there really 13 voltage inputs? Probably not...
73*7ebd8b66SMauro Carvalho Chehab  * Cleanups, no doubt...
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