1Kernel driver smsc47m1
2======================
3
4Supported chips:
5
6  * SMSC LPC47B27x, LPC47M112, LPC47M10x, LPC47M13x, LPC47M14x,
7
8    LPC47M15x and LPC47M192
9
10    Addresses scanned: none, address read from Super I/O config space
11
12    Prefix: 'smsc47m1'
13
14    Datasheets:
15
16	http://www.smsc.com/media/Downloads_Public/Data_Sheets/47b272.pdf
17
18	http://www.smsc.com/media/Downloads_Public/Data_Sheets/47m10x.pdf
19
20	http://www.smsc.com/media/Downloads_Public/Data_Sheets/47m112.pdf
21
22	http://www.smsc.com/
23
24  * SMSC LPC47M292
25
26    Addresses scanned: none, address read from Super I/O config space
27
28    Prefix: 'smsc47m2'
29
30    Datasheet: Not public
31
32  * SMSC LPC47M997
33
34    Addresses scanned: none, address read from Super I/O config space
35
36    Prefix: 'smsc47m1'
37
38    Datasheet: none
39
40
41
42Authors:
43
44     - Mark D. Studebaker <mdsxyz123@yahoo.com>,
45     - With assistance from Bruce Allen <ballen@uwm.edu>, and his
46       fan.c program:
47
48       - http://www.lsc-group.phys.uwm.edu/%7Eballen/driver/
49
50     - Gabriele Gorla <gorlik@yahoo.com>,
51     - Jean Delvare <jdelvare@suse.de>
52
53Description
54-----------
55
56The Standard Microsystems Corporation (SMSC) 47M1xx Super I/O chips
57contain monitoring and PWM control circuitry for two fans.
58
59The LPC47M15x, LPC47M192 and LPC47M292 chips contain a full 'hardware
60monitoring block' in addition to the fan monitoring and control. The
61hardware monitoring block is not supported by this driver, use the
62smsc47m192 driver for that.
63
64No documentation is available for the 47M997, but it has the same device
65ID as the 47M15x and 47M192 chips and seems to be compatible.
66
67Fan rotation speeds are reported in RPM (rotations per minute). An alarm is
68triggered if the rotation speed has dropped below a programmable limit. Fan
69readings can be divided by a programmable divider (1, 2, 4 or 8) to give
70the readings more range or accuracy. Not all RPM values can accurately be
71represented, so some rounding is done. With a divider of 2, the lowest
72representable value is around 2600 RPM.
73
74PWM values are from 0 to 255.
75
76If an alarm triggers, it will remain triggered until the hardware register
77is read at least once. This means that the cause for the alarm may
78already have disappeared! Note that in the current implementation, all
79hardware registers are read whenever any data is read (unless it is less
80than 1.5 seconds since the last update). This means that you can easily
81miss once-only alarms.
82
83------------------------------------------------------------------
84
85The lm_sensors project gratefully acknowledges the support of
86Intel in the development of this driver.
87