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diff --git a/Documentation/hwmon/da9055 b/Documentation/hwmon/da9055 new file mode 100644 index 000000000000..855c3f536e00 --- /dev/null +++ b/Documentation/hwmon/da9055 @@ -0,0 +1,47 @@ +Supported chips: + * Dialog Semiconductors DA9055 PMIC + Prefix: 'da9055' + Datasheet: Datasheet is not publicly available. + +Authors: David Dajun Chen <dchen@diasemi.com> + +Description +----------- + +The DA9055 provides an Analogue to Digital Converter (ADC) with 10 bits +resolution and track and hold circuitry combined with an analogue input +multiplexer. The analogue input multiplexer will allow conversion of up to 5 +different inputs. The track and hold circuit ensures stable input voltages at +the input of the ADC during the conversion. + +The ADC is used to measure the following inputs: +Channel 0: VDDOUT - measurement of the system voltage +Channel 1: ADC_IN1 - high impedance input (0 - 2.5V) +Channel 2: ADC_IN2 - high impedance input (0 - 2.5V) +Channel 3: ADC_IN3 - high impedance input (0 - 2.5V) +Channel 4: Internal Tjunc. - sense (internal temp. sensor) + +By using sysfs attributes we can measure the system voltage VDDOUT, +chip junction temperature and auxiliary channels voltages. + +Voltage Monitoring +------------------ + +Voltages are sampled in a AUTO mode it can be manually sampled too and results +are stored in a 10 bit ADC. + +The system voltage is calculated as: + Milli volt = ((ADC value * 1000) / 85) + 2500 + +The voltages on ADC channels 1, 2 and 3 are calculated as: + Milli volt = (ADC value * 1000) / 102 + +Temperature Monitoring +---------------------- + +Temperatures are sampled by a 10 bit ADC. Junction temperatures +are monitored by the ADC channels. + +The junction temperature is calculated: + Degrees celsius = -0.4084 * (ADC_RES - T_OFFSET) + 307.6332 +The junction temperature attribute is supported by the driver. |