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R.Marek@sh.cvut.cz7f15b662005-05-26 12:42:19 +00001Kernel driver smsc47m1
2======================
3
4Supported chips:
Jean Delvare60917802006-10-08 22:00:44 +02005 * SMSC LPC47B27x, LPC47M112, LPC47M10x, LPC47M13x, LPC47M14x,
6 LPC47M15x and LPC47M192
R.Marek@sh.cvut.cz7f15b662005-05-26 12:42:19 +00007 Addresses scanned: none, address read from Super I/O config space
8 Prefix: 'smsc47m1'
9 Datasheets:
Justin P. Mattock0ea6e612010-07-23 20:51:24 -070010 http://www.smsc.com/media/Downloads_Public/Data_Sheets/47b272.pdf
11 http://www.smsc.com/media/Downloads_Public/Data_Sheets/47m10x.pdf
12 http://www.smsc.com/media/Downloads_Public/Data_Sheets/47m112.pdf
13 http://www.smsc.com/
Jean Delvare8eccbb62007-05-08 17:21:59 +020014 * SMSC LPC47M292
15 Addresses scanned: none, address read from Super I/O config space
16 Prefix: 'smsc47m2'
17 Datasheet: Not public
Jean Delvareb890a072005-10-26 22:21:24 +020018 * SMSC LPC47M997
19 Addresses scanned: none, address read from Super I/O config space
20 Prefix: 'smsc47m1'
21 Datasheet: none
R.Marek@sh.cvut.cz7f15b662005-05-26 12:42:19 +000022
23Authors:
24 Mark D. Studebaker <mdsxyz123@yahoo.com>,
25 With assistance from Bruce Allen <ballen@uwm.edu>, and his
26 fan.c program: http://www.lsc-group.phys.uwm.edu/%7Eballen/driver/
27 Gabriele Gorla <gorlik@yahoo.com>,
28 Jean Delvare <khali@linux-fr.org>
29
30Description
31-----------
32
33The Standard Microsystems Corporation (SMSC) 47M1xx Super I/O chips
34contain monitoring and PWM control circuitry for two fans.
35
Jean Delvare8eccbb62007-05-08 17:21:59 +020036The LPC47M15x, LPC47M192 and LPC47M292 chips contain a full 'hardware
37monitoring block' in addition to the fan monitoring and control. The
38hardware monitoring block is not supported by this driver, use the
39smsc47m192 driver for that.
R.Marek@sh.cvut.cz7f15b662005-05-26 12:42:19 +000040
Jean Delvareb890a072005-10-26 22:21:24 +020041No documentation is available for the 47M997, but it has the same device
42ID as the 47M15x and 47M192 chips and seems to be compatible.
43
R.Marek@sh.cvut.cz7f15b662005-05-26 12:42:19 +000044Fan rotation speeds are reported in RPM (rotations per minute). An alarm is
45triggered if the rotation speed has dropped below a programmable limit. Fan
46readings can be divided by a programmable divider (1, 2, 4 or 8) to give
47the readings more range or accuracy. Not all RPM values can accurately be
48represented, so some rounding is done. With a divider of 2, the lowest
49representable value is around 2600 RPM.
50
51PWM values are from 0 to 255.
52
53If an alarm triggers, it will remain triggered until the hardware register
54is read at least once. This means that the cause for the alarm may
55already have disappeared! Note that in the current implementation, all
56hardware registers are read whenever any data is read (unless it is less
57than 1.5 seconds since the last update). This means that you can easily
58miss once-only alarms.
59
60
61**********************
62The lm_sensors project gratefully acknowledges the support of
63Intel in the development of this driver.