| Mark Brown | 08bad5a | 2009-07-28 15:52:22 +0100 | [diff] [blame^] | 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. |