xref: /OK3568_Linux_fs/kernel/Documentation/hwmon/wm831x.rst (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593SmuzhiyunKernel driver wm831x-hwmon
2*4882a593Smuzhiyun==========================
3*4882a593Smuzhiyun
4*4882a593SmuzhiyunSupported chips:
5*4882a593Smuzhiyun  * Wolfson Microelectronics WM831x PMICs
6*4882a593Smuzhiyun
7*4882a593Smuzhiyun    Prefix: 'wm831x'
8*4882a593Smuzhiyun
9*4882a593Smuzhiyun    Datasheet:
10*4882a593Smuzhiyun
11*4882a593Smuzhiyun	- http://www.wolfsonmicro.com/products/WM8310
12*4882a593Smuzhiyun	- http://www.wolfsonmicro.com/products/WM8311
13*4882a593Smuzhiyun	- http://www.wolfsonmicro.com/products/WM8312
14*4882a593Smuzhiyun
15*4882a593SmuzhiyunAuthors: Mark Brown <broonie@opensource.wolfsonmicro.com>
16*4882a593Smuzhiyun
17*4882a593SmuzhiyunDescription
18*4882a593Smuzhiyun-----------
19*4882a593Smuzhiyun
20*4882a593SmuzhiyunThe WM831x series of PMICs include an AUXADC which can be used to
21*4882a593Smuzhiyunmonitor a range of system operating parameters, including the voltages
22*4882a593Smuzhiyunof the major supplies within the system.  Currently the driver provides
23*4882a593Smuzhiyunreporting of all the input values but does not provide any alarms.
24*4882a593Smuzhiyun
25*4882a593SmuzhiyunVoltage Monitoring
26*4882a593Smuzhiyun------------------
27*4882a593Smuzhiyun
28*4882a593SmuzhiyunVoltages are sampled by a 12 bit ADC.  Voltages in millivolts are 1.465
29*4882a593Smuzhiyuntimes the ADC value.
30*4882a593Smuzhiyun
31*4882a593SmuzhiyunTemperature Monitoring
32*4882a593Smuzhiyun----------------------
33*4882a593Smuzhiyun
34*4882a593SmuzhiyunTemperatures are sampled by a 12 bit ADC.  Chip and battery temperatures
35*4882a593Smuzhiyunare available.  The chip temperature is calculated as:
36*4882a593Smuzhiyun
37*4882a593Smuzhiyun	Degrees celsius = (512.18 - data) / 1.0983
38*4882a593Smuzhiyun
39*4882a593Smuzhiyunwhile the battery temperature calculation will depend on the NTC
40*4882a593Smuzhiyunthermistor component.
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