projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| df922703 ML |
1 | Kernel driver ltc2990 |
| 2 | ===================== | |
| 3 | ||
| 4 | Supported chips: | |
| 5 | * Linear Technology LTC2990 | |
| 6 | Prefix: 'ltc2990' | |
| 7 | Addresses scanned: - | |
| 8 | Datasheet: http://www.linear.com/product/ltc2990 | |
| 9 | ||
| 10 | Author: Mike Looijmans <mike.looijmans@topic.nl> | |
| 11 | ||
| 12 | ||
| 13 | Description | |
| 14 | ----------- | |
| 15 | ||
| 16 | LTC2990 is a Quad I2C Voltage, Current and Temperature Monitor. | |
| 17 | The chip's inputs can measure 4 voltages, or two inputs together (1+2 and 3+4) | |
| 18 | can be combined to measure a differential voltage, which is typically used to | |
| 19 | measure current through a series resistor, or a temperature. | |
| 20 | ||
| 21 | This driver currently uses the 2x differential mode only. In order to support | |
| 22 | other modes, the driver will need to be expanded. | |
| 23 | ||
| 24 | ||
| 25 | Usage Notes | |
| 26 | ----------- | |
| 27 | ||
| 28 | This driver does not probe for PMBus devices. You will have to instantiate | |
| 29 | devices explicitly. | |
| 30 | ||
| 31 | ||
| 32 | Sysfs attributes | |
| 33 | ---------------- | |
| 34 | ||
| 35 | The "curr*_input" measurements actually report the voltage drop across the | |
| 36 | input pins in microvolts. This is equivalent to the current through a 1mOhm | |
| 37 | sense resistor. Divide the reported value by the actual sense resistor value | |
| 38 | in mOhm to get the actual value. | |
| 39 | ||
| 40 | in0_input Voltage at Vcc pin in millivolt (range 2.5V to 5V) | |
| 41 | temp1_input Internal chip temperature in millidegrees Celcius | |
| 42 | curr1_input Current in mA across v1-v2 assuming a 1mOhm sense resistor. | |
| 43 | curr2_input Current in mA across v3-v4 assuming a 1mOhm sense resistor. |