1*9f3a352eSJishnu Prakash# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) 2*9f3a352eSJishnu Prakash%YAML 1.2 3*9f3a352eSJishnu Prakash--- 4*9f3a352eSJishnu Prakash$id: http://devicetree.org/schemas/iio/adc/qcom,spmi-vadc-common.yaml# 5*9f3a352eSJishnu Prakash$schema: http://devicetree.org/meta-schemas/core.yaml# 6*9f3a352eSJishnu Prakash 7*9f3a352eSJishnu Prakashtitle: Qualcomm Technologies, Inc. SPMI PMIC ADC channels 8*9f3a352eSJishnu Prakash 9*9f3a352eSJishnu Prakashmaintainers: 10*9f3a352eSJishnu Prakash - Jishnu Prakash <jishnu.prakash@oss.qualcomm.com> 11*9f3a352eSJishnu Prakash 12*9f3a352eSJishnu Prakashdescription: 13*9f3a352eSJishnu Prakash This defines the common properties used to define Qualcomm VADC channels. 14*9f3a352eSJishnu Prakash 15*9f3a352eSJishnu Prakashproperties: 16*9f3a352eSJishnu Prakash reg: 17*9f3a352eSJishnu Prakash description: 18*9f3a352eSJishnu Prakash ADC channel number (PMIC-specific for versions after PMIC5 ADC). 19*9f3a352eSJishnu Prakash maxItems: 1 20*9f3a352eSJishnu Prakash 21*9f3a352eSJishnu Prakash label: 22*9f3a352eSJishnu Prakash description: 23*9f3a352eSJishnu Prakash ADC input of the platform as seen in the schematics. 24*9f3a352eSJishnu Prakash For thermistor inputs connected to generic AMUX or GPIO inputs 25*9f3a352eSJishnu Prakash these can vary across platform for the same pins. Hence select 26*9f3a352eSJishnu Prakash the platform schematics name for this channel. 27*9f3a352eSJishnu Prakash 28*9f3a352eSJishnu Prakash qcom,decimation: 29*9f3a352eSJishnu Prakash $ref: /schemas/types.yaml#/definitions/uint32 30*9f3a352eSJishnu Prakash description: 31*9f3a352eSJishnu Prakash This parameter is used to decrease ADC sampling rate. 32*9f3a352eSJishnu Prakash Quicker measurements can be made by reducing decimation ratio. 33*9f3a352eSJishnu Prakash 34*9f3a352eSJishnu Prakash qcom,pre-scaling: 35*9f3a352eSJishnu Prakash $ref: /schemas/types.yaml#/definitions/uint32-array 36*9f3a352eSJishnu Prakash description: 37*9f3a352eSJishnu Prakash Used for scaling the channel input signal before the signal is 38*9f3a352eSJishnu Prakash fed to VADC. The configuration for this node is to know the 39*9f3a352eSJishnu Prakash pre-determined ratio and use it for post scaling. It is a pair of 40*9f3a352eSJishnu Prakash integers, denoting the numerator and denominator of the fraction by which 41*9f3a352eSJishnu Prakash input signal is multiplied. For example, <1 3> indicates the signal is scaled 42*9f3a352eSJishnu Prakash down to 1/3 of its value before ADC measurement. 43*9f3a352eSJishnu Prakash If property is not found default value depending on chip will be used. 44*9f3a352eSJishnu Prakash oneOf: 45*9f3a352eSJishnu Prakash - items: 46*9f3a352eSJishnu Prakash - const: 1 47*9f3a352eSJishnu Prakash - enum: [ 1, 3, 4, 6, 20, 8, 10, 16 ] 48*9f3a352eSJishnu Prakash - items: 49*9f3a352eSJishnu Prakash - const: 10 50*9f3a352eSJishnu Prakash - const: 81 51*9f3a352eSJishnu Prakash 52*9f3a352eSJishnu Prakash qcom,ratiometric: 53*9f3a352eSJishnu Prakash type: boolean 54*9f3a352eSJishnu Prakash description: | 55*9f3a352eSJishnu Prakash Channel calibration type. 56*9f3a352eSJishnu Prakash - For compatible property "qcom,spmi-vadc", if this property is 57*9f3a352eSJishnu Prakash specified VADC will use the VDD reference (1.8V) and GND for 58*9f3a352eSJishnu Prakash channel calibration. If property is not found, channel will be 59*9f3a352eSJishnu Prakash calibrated with 0.625V and 1.25V reference channels, also 60*9f3a352eSJishnu Prakash known as absolute calibration. 61*9f3a352eSJishnu Prakash - For other compatible properties, if this property is specified 62*9f3a352eSJishnu Prakash VADC will use the VDD reference (1.875V) and GND for channel 63*9f3a352eSJishnu Prakash calibration. If property is not found, channel will be calibrated 64*9f3a352eSJishnu Prakash with 0V and 1.25V reference channels, also known as absolute calibration. 65*9f3a352eSJishnu Prakash 66*9f3a352eSJishnu Prakash qcom,hw-settle-time: 67*9f3a352eSJishnu Prakash $ref: /schemas/types.yaml#/definitions/uint32 68*9f3a352eSJishnu Prakash description: | 69*9f3a352eSJishnu Prakash Time between AMUX getting configured and the ADC starting 70*9f3a352eSJishnu Prakash conversion. The 'hw_settle_time' is an index used from valid values 71*9f3a352eSJishnu Prakash and programmed in hardware to achieve the hardware settling delay. 72*9f3a352eSJishnu Prakash 73*9f3a352eSJishnu Prakash qcom,avg-samples: 74*9f3a352eSJishnu Prakash $ref: /schemas/types.yaml#/definitions/uint32 75*9f3a352eSJishnu Prakash description: | 76*9f3a352eSJishnu Prakash Number of samples to be used for measurement. 77*9f3a352eSJishnu Prakash Averaging provides the option to obtain a single measurement 78*9f3a352eSJishnu Prakash from the ADC that is an average of multiple samples. The value 79*9f3a352eSJishnu Prakash selected is 2^(value). 80*9f3a352eSJishnu Prakash 81*9f3a352eSJishnu Prakashrequired: 82*9f3a352eSJishnu Prakash - reg 83*9f3a352eSJishnu Prakash 84*9f3a352eSJishnu PrakashadditionalProperties: true 85