08bad5a821
This driver adds support for the hardware monitoring features of the WM831x PMICs to the hwmon API. Monitoring is provided for the system voltages supported natively by the WM831x, the chip temperature, the battery temperature and the auxiliary inputs of the WM831x. Currently no alarms are supported, though digital comparators on the WM831x devices would allow these to be provided. Since the auxiliary and battery temperature input scaling depends on the system configuration the value is reported as a voltage to userspace. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
37 lines
1.1 KiB
Text
37 lines
1.1 KiB
Text
Kernel driver wm831x-hwmon
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==========================
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Supported chips:
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* Wolfson Microelectronics WM831x PMICs
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Prefix: 'wm831x'
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Datasheet:
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http://www.wolfsonmicro.com/products/WM8310
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http://www.wolfsonmicro.com/products/WM8311
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http://www.wolfsonmicro.com/products/WM8312
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Authors: Mark Brown <broonie@opensource.wolfsonmicro.com>
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Description
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-----------
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The WM831x series of PMICs include an AUXADC which can be used to
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monitor a range of system operating parameters, including the voltages
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of the major supplies within the system. Currently the driver provides
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reporting of all the input values but does not provide any alarms.
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Voltage Monitoring
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------------------
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Voltages are sampled by a 12 bit ADC. Voltages in milivolts are 1.465
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times the ADC value.
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Temperature Monitoring
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----------------------
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Temperatures are sampled by a 12 bit ADC. Chip and battery temperatures
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are available. The chip temperature is calculated as:
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Degrees celsius = (512.18 - data) / 1.0983
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while the battery temperature calculation will depend on the NTC
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thermistor component.
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