|  | Kernel driver smsc47m1 | 
|  | ====================== | 
|  |  | 
|  | Supported chips: | 
|  | * SMSC LPC47B27x, LPC47M112, LPC47M10x, LPC47M13x, LPC47M14x, | 
|  | LPC47M15x and LPC47M192 | 
|  | Addresses scanned: none, address read from Super I/O config space | 
|  | Prefix: 'smsc47m1' | 
|  | Datasheets: | 
|  | http://www.smsc.com/media/Downloads_Public/Data_Sheets/47b272.pdf | 
|  | http://www.smsc.com/media/Downloads_Public/Data_Sheets/47m10x.pdf | 
|  | http://www.smsc.com/media/Downloads_Public/Data_Sheets/47m112.pdf | 
|  | http://www.smsc.com/ | 
|  | * SMSC LPC47M292 | 
|  | Addresses scanned: none, address read from Super I/O config space | 
|  | Prefix: 'smsc47m2' | 
|  | Datasheet: Not public | 
|  | * SMSC LPC47M997 | 
|  | Addresses scanned: none, address read from Super I/O config space | 
|  | Prefix: 'smsc47m1' | 
|  | Datasheet: none | 
|  |  | 
|  | 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 LPC47M15x, LPC47M192 and LPC47M292 chips contain a full 'hardware | 
|  | monitoring block' in addition to the fan monitoring and control. The | 
|  | hardware monitoring block is not supported by this driver, use the | 
|  | smsc47m192 driver for that. | 
|  |  | 
|  | No documentation is available for the 47M997, but it has the same device | 
|  | ID as the 47M15x and 47M192 chips and seems to be compatible. | 
|  |  | 
|  | 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. |