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diff --git a/Documentation/i2c/chips/lm63 b/Documentation/i2c/chips/lm63 deleted file mode 100644 index 31660bf9797..00000000000 --- a/Documentation/i2c/chips/lm63 +++ /dev/null @@ -1,57 +0,0 @@ -Kernel driver lm63 -================== - -Supported chips: - * National Semiconductor LM63 - Prefix: 'lm63' - Addresses scanned: I2C 0x4c - Datasheet: Publicly available at the National Semiconductor website - http://www.national.com/pf/LM/LM63.html - -Author: Jean Delvare <khali@linux-fr.org> - -Thanks go to Tyan and especially Alex Buckingham for setting up a remote -access to their S4882 test platform for this driver. - http://www.tyan.com/ - -Description ------------ - -The LM63 is a digital temperature sensor with integrated fan monitoring -and control. - -The LM63 is basically an LM86 with fan speed monitoring and control -capabilities added. It misses some of the LM86 features though: - - No low limit for local temperature. - - No critical limit for local temperature. - - Critical limit for remote temperature can be changed only once. We - will consider that the critical limit is read-only. - -The datasheet isn't very clear about what the tachometer reading is. - -An explanation from National Semiconductor: The two lower bits of the read -value have to be masked out. The value is still 16 bit in width. - -All temperature values are given in degrees Celsius. Resolution is 1.0 -degree for the local temperature, 0.125 degree for the remote temperature. - -The fan speed is measured using a tachometer. Contrary to most chips which -store the value in an 8-bit register and have a selectable clock divider -to make sure that the result will fit in the register, the LM63 uses 16-bit -value for measuring the speed of the fan. It can measure fan speeds down to -83 RPM, at least in theory. - -Note that the pin used for fan monitoring is shared with an alert out -function. Depending on how the board designer wanted to use the chip, fan -speed monitoring will or will not be possible. The proper chip configuration -is left to the BIOS, and the driver will blindly trust it. - -A PWM output can be used to control the speed of the fan. The LM63 has two -PWM modes: manual and automatic. Automatic mode is not fully implemented yet -(you cannot define your custom PWM/temperature curve), and mode change isn't -supported either. - -The lm63 driver will not update its values more frequently than every -second; reading them more often will do no harm, but will return 'old' -values. - |