| Kernel driver smsc47m1 |
| ====================== |
| |
| Supported chips: |
| * SMSC LPC47B27x, LPC47M10x, LPC47M13x, LPC47M14x, LPC47M15x and LPC47M192 |
| Addresses scanned: none, address read from Super I/O config space |
| Prefix: 'smsc47m1' |
| Datasheets: |
| http://www.smsc.com/main/datasheets/47b27x.pdf |
| http://www.smsc.com/main/datasheets/47m10x.pdf |
| http://www.smsc.com/main/tools/discontinued/47m13x.pdf |
| http://www.smsc.com/main/datasheets/47m14x.pdf |
| http://www.smsc.com/main/tools/discontinued/47m15x.pdf |
| http://www.smsc.com/main/datasheets/47m192.pdf |
| |
| Authors: |
| Mark D. Studebaker <mdsxyz123@yahoo.com>, |
| With assistance from Bruce Allen <ballen@uwm.edu>, and his |
| fan.c program: http://www.lsc-group.phys.uwm.edu/%7Eballen/driver/ |
| Gabriele Gorla <gorlik@yahoo.com>, |
| Jean Delvare <khali@linux-fr.org> |
| |
| Description |
| ----------- |
| |
| The Standard Microsystems Corporation (SMSC) 47M1xx Super I/O chips |
| contain monitoring and PWM control circuitry for two fans. |
| |
| The 47M15x and 47M192 chips contain a full 'hardware monitoring block' |
| in addition to the fan monitoring and control. The hardware monitoring |
| block is not supported by the driver. |
| |
| Fan rotation speeds are reported in RPM (rotations per minute). An alarm is |
| triggered if the rotation speed has dropped below a programmable limit. Fan |
| readings can be divided by a programmable divider (1, 2, 4 or 8) to give |
| the readings more range or accuracy. Not all RPM values can accurately be |
| represented, so some rounding is done. With a divider of 2, the lowest |
| representable value is around 2600 RPM. |
| |
| PWM values are from 0 to 255. |
| |
| If an alarm triggers, it will remain triggered until the hardware register |
| is read at least once. This means that the cause for the alarm may |
| already have disappeared! Note that in the current implementation, all |
| hardware registers are read whenever any data is read (unless it is less |
| than 1.5 seconds since the last update). This means that you can easily |
| miss once-only alarms. |
| |
| |
| ********************** |
| The lm_sensors project gratefully acknowledges the support of |
| Intel in the development of this driver. |