LXR linux/Documentation/hwmon/smsc47m1.rst

   1Kernel driver smsc47m1
   2======================
   3
   4Supported chips:
   5
   6  * SMSC LPC47B27x, LPC47M112, LPC47M10x, LPC47M13x, LPC47M14x,
   7
   8    LPC47M15x and LPC47M192
   9
  10    Addresses scanned: none, address read from Super I/O config space
  11
  12    Prefix: 'smsc47m1'
  13
  14    Datasheets:
  15
  16        http://www.smsc.com/media/Downloads_Public/Data_Sheets/47b272.pdf
  17
  18        http://www.smsc.com/media/Downloads_Public/Data_Sheets/47m10x.pdf
  19
  20        http://www.smsc.com/media/Downloads_Public/Data_Sheets/47m112.pdf
  21
  22        http://www.smsc.com/
  23
  24  * SMSC LPC47M292
  25
  26    Addresses scanned: none, address read from Super I/O config space
  27
  28    Prefix: 'smsc47m2'
  29
  30    Datasheet: Not public
  31
  32  * SMSC LPC47M997
  33
  34    Addresses scanned: none, address read from Super I/O config space
  35
  36    Prefix: 'smsc47m1'
  37
  38    Datasheet: none
  39
  40
  41
  42Authors:
  43
  44     - Mark D. Studebaker <mdsxyz123@yahoo.com>,
  45     - With assistance from Bruce Allen <ballen@uwm.edu>, and his
  46       fan.c program:
  47
  48       - http://www.lsc-group.phys.uwm.edu/%7Eballen/driver/
  49
  50     - Gabriele Gorla <gorlik@yahoo.com>,
  51     - Jean Delvare <jdelvare@suse.de>
  52
  53Description
  54-----------
  55
  56The Standard Microsystems Corporation (SMSC) 47M1xx Super I/O chips
  57contain monitoring and PWM control circuitry for two fans.
  58
  59The LPC47M15x, LPC47M192 and LPC47M292 chips contain a full 'hardware
  60monitoring block' in addition to the fan monitoring and control. The
  61hardware monitoring block is not supported by this driver, use the
  62smsc47m192 driver for that.
  63
  64No documentation is available for the 47M997, but it has the same device
  65ID as the 47M15x and 47M192 chips and seems to be compatible.
  66
  67Fan rotation speeds are reported in RPM (rotations per minute). An alarm is
  68triggered if the rotation speed has dropped below a programmable limit. Fan
  69readings can be divided by a programmable divider (1, 2, 4 or 8) to give
  70the readings more range or accuracy. Not all RPM values can accurately be
  71represented, so some rounding is done. With a divider of 2, the lowest
  72representable value is around 2600 RPM.
  73
  74PWM values are from 0 to 255.
  75
  76If an alarm triggers, it will remain triggered until the hardware register
  77is read at least once. This means that the cause for the alarm may
  78already have disappeared! Note that in the current implementation, all
  79hardware registers are read whenever any data is read (unless it is less
  80than 1.5 seconds since the last update). This means that you can easily
  81miss once-only alarms.
  82
  83------------------------------------------------------------------
  84
  85The lm_sensors project gratefully acknowledges the support of
  86Intel in the development of this driver.
  87