| Jean Delvare | ba224e2 | 2006-12-12 18:18:29 +0100 | [diff] [blame] | 1 | Kernel driver pc87427 |
| 2 | ===================== |
| 3 | |
| 4 | Supported chips: |
| 5 | * National Semiconductor PC87427 |
| 6 | Prefix: 'pc87427' |
| 7 | Addresses scanned: none, address read from Super I/O config space |
| 8 | Datasheet: http://www.winbond.com.tw/E-WINBONDHTM/partner/apc_007.html |
| 9 | |
| 10 | Author: Jean Delvare <khali@linux-fr.org> |
| 11 | |
| 12 | Thanks to Amir Habibi at Candelis for setting up a test system, and to |
| 13 | Michael Kress for testing several iterations of this driver. |
| 14 | |
| 15 | |
| 16 | Description |
| 17 | ----------- |
| 18 | |
| 19 | The National Semiconductor Super I/O chip includes complete hardware |
| 20 | monitoring capabilities. It can monitor up to 18 voltages, 8 fans and |
| 21 | 6 temperature sensors. Only the fans are supported at the moment. |
| 22 | |
| 23 | This chip also has fan controlling features, which are not yet supported |
| 24 | by this driver either. |
| 25 | |
| 26 | The driver assumes that no more than one chip is present, which seems |
| 27 | reasonable. |
| 28 | |
| 29 | |
| 30 | Fan Monitoring |
| 31 | -------------- |
| 32 | |
| 33 | Fan rotation speeds are reported as 14-bit values from a gated clock |
| 34 | signal. Speeds down to 83 RPM can be measured. |
| 35 | |
| 36 | An alarm is triggered if the rotation speed drops below a programmable |
| 37 | limit. Another alarm is triggered if the speed is too low to to be measured |
| 38 | (including stalled or missing fan). |