Commit | Line | Data |
---|---|---|
7f15b664 RM |
1 | Kernel driver smsc47m1 |
2 | ====================== | |
3 | ||
4 | Supported 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 | ||
16 | Authors: | |
17 | Mark D. Studebaker <mdsxyz123@yahoo.com>, | |
18 | With assistance from Bruce Allen <ballen@uwm.edu>, and his | |
19 | fan.c program: http://www.lsc-group.phys.uwm.edu/%7Eballen/driver/ | |
20 | Gabriele Gorla <gorlik@yahoo.com>, | |
21 | Jean Delvare <khali@linux-fr.org> | |
22 | ||
23 | Description | |
24 | ----------- | |
25 | ||
26 | The Standard Microsystems Corporation (SMSC) 47M1xx Super I/O chips | |
27 | contain monitoring and PWM control circuitry for two fans. | |
28 | ||
29 | The 47M15x and 47M192 chips contain a full 'hardware monitoring block' | |
30 | in addition to the fan monitoring and control. The hardware monitoring | |
31 | block is not supported by the driver. | |
32 | ||
33 | Fan rotation speeds are reported in RPM (rotations per minute). An alarm is | |
34 | triggered if the rotation speed has dropped below a programmable limit. Fan | |
35 | readings can be divided by a programmable divider (1, 2, 4 or 8) to give | |
36 | the readings more range or accuracy. Not all RPM values can accurately be | |
37 | represented, so some rounding is done. With a divider of 2, the lowest | |
38 | representable value is around 2600 RPM. | |
39 | ||
40 | PWM values are from 0 to 255. | |
41 | ||
42 | If an alarm triggers, it will remain triggered until the hardware register | |
43 | is read at least once. This means that the cause for the alarm may | |
44 | already have disappeared! Note that in the current implementation, all | |
45 | hardware registers are read whenever any data is read (unless it is less | |
46 | than 1.5 seconds since the last update). This means that you can easily | |
47 | miss once-only alarms. | |
48 | ||
49 | ||
50 | ********************** | |
51 | The lm_sensors project gratefully acknowledges the support of | |
52 | Intel in the development of this driver. |