tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1Kernel driver smsc47m1
2======================
3
4Supported chips:
5 * SMSC LPC47B27x, LPC47M10x, LPC47M13x, LPC47M14x, LPC47M15x and LPC47M192
6 Addresses scanned: none, address read from Super I/O config space
7 Prefix: 'smsc47m1'
8 Datasheets:
9 http://www.smsc.com/main/datasheets/47b27x.pdf
10 http://www.smsc.com/main/datasheets/47m10x.pdf
11 http://www.smsc.com/main/tools/discontinued/47m13x.pdf
12 http://www.smsc.com/main/datasheets/47m14x.pdf
13 http://www.smsc.com/main/tools/discontinued/47m15x.pdf
14 http://www.smsc.com/main/datasheets/47m192.pdf
15 * SMSC LPC47M997
16 Addresses scanned: none, address read from Super I/O config space
17 Prefix: 'smsc47m1'
18 Datasheet: none
19
20Authors:
21 Mark D. Studebaker <mdsxyz123@yahoo.com>,
22 With assistance from Bruce Allen <ballen@uwm.edu>, and his
23 fan.c program: http://www.lsc-group.phys.uwm.edu/%7Eballen/driver/
24 Gabriele Gorla <gorlik@yahoo.com>,
25 Jean Delvare <khali@linux-fr.org>
26
27Description
28-----------
29
30The Standard Microsystems Corporation (SMSC) 47M1xx Super I/O chips
31contain monitoring and PWM control circuitry for two fans.
32
33The 47M15x and 47M192 chips contain a full 'hardware monitoring block'
34in addition to the fan monitoring and control. The hardware monitoring
35block is not supported by the driver.
36
37No documentation is available for the 47M997, but it has the same device
38ID as the 47M15x and 47M192 chips and seems to be compatible.
39
40Fan rotation speeds are reported in RPM (rotations per minute). An alarm is
41triggered if the rotation speed has dropped below a programmable limit. Fan
42readings can be divided by a programmable divider (1, 2, 4 or 8) to give
43the readings more range or accuracy. Not all RPM values can accurately be
44represented, so some rounding is done. With a divider of 2, the lowest
45representable value is around 2600 RPM.
46
47PWM values are from 0 to 255.
48
49If an alarm triggers, it will remain triggered until the hardware register
50is read at least once. This means that the cause for the alarm may
51already have disappeared! Note that in the current implementation, all
52hardware registers are read whenever any data is read (unless it is less
53than 1.5 seconds since the last update). This means that you can easily
54miss once-only alarms.
55
56
57**********************
58The lm_sensors project gratefully acknowledges the support of
59Intel in the development of this driver.