Kernel driver pc87427 ===================== Supported chips: * National Semiconductor PC87427 Prefix: 'pc87427' Addresses scanned: none, address read from Super I/O config space Datasheet: No longer available Author: Jean Delvare Thanks to Amir Habibi at Candelis for setting up a test system, and to Michael Kress for testing several iterations of this driver. Description ----------- The National Semiconductor Super I/O chip includes complete hardware monitoring capabilities. It can monitor up to 18 voltages, 8 fans and 6 temperature sensors. Only the fans are supported at the moment. This chip also has fan controlling features, which are not yet supported by this driver either. The driver assumes that no more than one chip is present, which seems reasonable. Fan Monitoring -------------- Fan rotation speeds are reported as 14-bit values from a gated clock signal. Speeds down to 83 RPM can be measured. An alarm is triggered if the rotation speed drops below a programmable limit. Another alarm is triggered if the speed is too low to be measured (including stalled or missing fan).