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