projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 08bad5a8 MB |
1 | Kernel driver wm831x-hwmon |
| 2 | ========================== | |
| 3 | ||
| 4 | Supported chips: | |
| 5 | * Wolfson Microelectronics WM831x PMICs | |
| 4f1158b3 | 6 | |
| 08bad5a8 | 7 | Prefix: 'wm831x' |
| 4f1158b3 | 8 | |
| 08bad5a8 | 9 | Datasheet: |
| 4f1158b3 MCC |
10 | |
| 11 | - http://www.wolfsonmicro.com/products/WM8310 | |
| 12 | - http://www.wolfsonmicro.com/products/WM8311 | |
| 13 | - http://www.wolfsonmicro.com/products/WM8312 | |
| 08bad5a8 MB |
14 | |
| 15 | Authors: Mark Brown <broonie@opensource.wolfsonmicro.com> | |
| 16 | ||
| 17 | Description | |
| 18 | ----------- | |
| 19 | ||
| 20 | The WM831x series of PMICs include an AUXADC which can be used to | |
| 21 | monitor a range of system operating parameters, including the voltages | |
| 22 | of the major supplies within the system. Currently the driver provides | |
| 23 | reporting of all the input values but does not provide any alarms. | |
| 24 | ||
| 25 | Voltage Monitoring | |
| 26 | ------------------ | |
| 27 | ||
| 91fe4d50 | 28 | Voltages are sampled by a 12 bit ADC. Voltages in millivolts are 1.465 |
| 08bad5a8 MB |
29 | times the ADC value. |
| 30 | ||
| 31 | Temperature Monitoring | |
| 32 | ---------------------- | |
| 33 | ||
| 34 | Temperatures are sampled by a 12 bit ADC. Chip and battery temperatures | |
| 35 | are available. The chip temperature is calculated as: | |
| 36 | ||
| 37 | Degrees celsius = (512.18 - data) / 1.0983 | |
| 38 | ||
| 39 | while the battery temperature calculation will depend on the NTC | |
| 40 | thermistor component. |