Kernel driver `lm90.o'
=====================

Status: Complete but untested

Supported chips: 
  * National Semiconductor LM90
    Prefix: `lm90'
    Addresses scanned: I2C 0x4c
    Datasheet: Publicly available at the National Semiconductor website
               http://www.national.com/pf/LM/LM90.html


Author: Jean Delvare <khali@linux-fr.org>

License: GPL


Module Parameters
-----------------

* force: short array (min = 1, max = 48)
  List of adapter,address pairs to boldly assume to be present
* force_lm90: short array (min = 1, max = 48)
  List of adapter,address pairs which are unquestionably assumed to contain
  a `lm90' chip
* probe: short array (min = 1, max = 48)
  List of adapter,address pairs to scan additionally
* probe_range: short array (min = 1, max = 48)
  List of adapter,start-addr,end-addr triples to scan additionally
* ignore: short array (min = 1, max = 48)
  List of adapter,address pairs not to scan
* ignore_range: short array (min = 1, max = 48)
  List of adapter,start-addr,end-addr triples not to scan


Description
-----------

The LM90 is a digital temperature sensor. It senses its own temperature as
well as the temperature of up to one external diode. It is compatible
with many other devices such as the LM86, the LM89, the ADM1032, the
MAX6657 and the MAX6658. The particularity of the LM90 over the LM84 for
example is that it features critical limits with hysteresis, and an
increased resolution of the remote temperature measurement.

Using the adm1021 or lm83 drivers for a LM90 should work, but the extra
features won't be supported.

The LM90 is found on many motherboards, too many for an exhaustive listing.
A list of confirmed motherboards follows. If you think the list is wrong or
want to add a specific motherboard to it, contact us.

Confirmed motherboards:
    Gigabyte    GA-7VAX
    Gigabyte    GA-7VRXP

The driver is untested so far. We want testers! Let us know if you want to
help.

All temperature values are given in degrees Celcius. Local and remote
temperatures are given within a range of +25 to +125 degrees. Resolution
is 1.0 degree for the local temperature, 0.125 degree for the remote
temperature. Accuracy is guaranteed to 4.0 degrees, but should reach
1.5 degree (local) and 3.0 degrees (remote) under typical conditions (see
the datasheet for more details).

Each sensor has its own high and low limits, plus a critical limit.
Additionally, there is a relative hysteresis value common to both critical
values.

The lm90 driver will not update its values more frequently than every
other second; reading them more often will do no harm, but will return
'old' values.


Chip Features
-------------

Chip 'lm90'

LABEL                 LABEL CLASS           COMPUTE CLASS          MODE  MAGN
temp1                 -                     -                       R-     0
temp1_high            temp1                 temp1                   RW     0
temp1_low             temp1                 temp1                   RW     0
temp2                 -                     -                       R-     1
temp2_high            temp2                 temp2                   RW     1
temp2_low             temp2                 temp2                   RW     1
tcrit1                temp1                 temp1                   RW     0
tcrit2                temp2                 temp2                   RW     0
hyst                  -                     -                       RW     0
alarms                -                     -                       R-     0

LABEL                 FEATURE SYMBOL                              SYSCTL FILE:N
temp1                 SENSORS_LM90_LOCAL_TEMP                           temp1:3
temp1_high            SENSORS_LM90_LOCAL_HIGH                           temp1:1
temp1_low             SENSORS_LM90_LOCAL_LOW                            temp1:2
temp2                 SENSORS_LM90_REMOTE_TEMP                          temp2:3
temp2_high            SENSORS_LM90_REMOTE_HIGH                          temp2:1
temp2_low             SENSORS_LM90_REMOTE_LOW                           temp2:2
tcrit1                SENSORS_LM90_LOCAL_TCRIT                         tcrit1:1
tcrit2                SENSORS_LM90_REMOTE_TCRIT                        tcrit2:1
hyst                  SENSORS_LM90_TCRIT_HYST                            hyst:1
alarms                SENSORS_LM90_ALARMS                              alarms:1
