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diff --git a/Documentation/i2c/chips/lm80 b/Documentation/i2c/chips/lm80 deleted file mode 100644 index cb5b407ba3e..00000000000 --- a/Documentation/i2c/chips/lm80 +++ /dev/null @@ -1,56 +0,0 @@ -Kernel driver lm80 -================== - -Supported chips: - * National Semiconductor LM80 - Prefix: 'lm80' - Addresses scanned: I2C 0x28 - 0x2f - Datasheet: Publicly available at the National Semiconductor website - http://www.national.com/ - -Authors: - Frodo Looijaard <frodol@dds.nl>, - Philip Edelbrock <phil@netroedge.com> - -Description ------------ - -This driver implements support for the National Semiconductor LM80. -It is described as a 'Serial Interface ACPI-Compatible Microprocessor -System Hardware Monitor'. - -The LM80 implements one temperature sensor, two fan rotation speed sensors, -seven voltage sensors, alarms, and some miscellaneous stuff. - -Temperatures are measured in degrees Celsius. There are two sets of limits -which operate independently. When the HOT Temperature Limit is crossed, -this will cause an alarm that will be reasserted until the temperature -drops below the HOT Hysteresis. The Overtemperature Shutdown (OS) limits -should work in the same way (but this must be checked; the datasheet -is unclear about this). Measurements are guaranteed between -55 and -+125 degrees. The current temperature measurement has a resolution of -0.0625 degrees; the limits have a resolution of 1 degree. - -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. - -Voltage sensors (also known as IN sensors) report their values in volts. -An alarm is triggered if the voltage has crossed a programmable minimum -or maximum limit. Note that minimum in this case always means 'closest to -zero'; this is important for negative voltage measurements. All voltage -inputs can measure voltages between 0 and 2.55 volts, with a resolution -of 0.01 volt. - -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 2.0 seconds since the last update). This means that you can easily -miss once-only alarms. - -The LM80 only updates its values each 1.5 seconds; reading it more often -will do no harm, but will return 'old' values. |