| 1234567891011121314151617181920212223242526272829303132333435363738394041424344454647 |
- 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 <khali@linux-fr.org>
- 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 (up to 4 PWM outputs),
- which are partly supported by this driver.
- 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).
- Fan Speed Control
- -----------------
- Fan speed can be controlled by PWM outputs. There are 4 possible modes:
- always off, always on, manual and automatic. The latter isn't supported
- by the driver: you can only return to that mode if it was the original
- setting, and the configuration interface is missing.
|
