85 lines
3.1 KiB
YAML
85 lines
3.1 KiB
YAML
# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
|
|
%YAML 1.2
|
|
---
|
|
$id: http://devicetree.org/schemas/iio/adc/qcom,spmi-vadc-common.yaml#
|
|
$schema: http://devicetree.org/meta-schemas/core.yaml#
|
|
|
|
title: Qualcomm Technologies, Inc. SPMI PMIC ADC channels
|
|
|
|
maintainers:
|
|
- Jishnu Prakash <jishnu.prakash@oss.qualcomm.com>
|
|
|
|
description:
|
|
This defines the common properties used to define Qualcomm VADC channels.
|
|
|
|
properties:
|
|
reg:
|
|
description:
|
|
ADC channel number (PMIC-specific for versions after PMIC5 ADC).
|
|
maxItems: 1
|
|
|
|
label:
|
|
description:
|
|
ADC input of the platform as seen in the schematics.
|
|
For thermistor inputs connected to generic AMUX or GPIO inputs
|
|
these can vary across platform for the same pins. Hence select
|
|
the platform schematics name for this channel.
|
|
|
|
qcom,decimation:
|
|
$ref: /schemas/types.yaml#/definitions/uint32
|
|
description:
|
|
This parameter is used to decrease ADC sampling rate.
|
|
Quicker measurements can be made by reducing decimation ratio.
|
|
|
|
qcom,pre-scaling:
|
|
$ref: /schemas/types.yaml#/definitions/uint32-array
|
|
description:
|
|
Used for scaling the channel input signal before the signal is
|
|
fed to VADC. The configuration for this node is to know the
|
|
pre-determined ratio and use it for post scaling. It is a pair of
|
|
integers, denoting the numerator and denominator of the fraction by which
|
|
input signal is multiplied. For example, <1 3> indicates the signal is scaled
|
|
down to 1/3 of its value before ADC measurement.
|
|
If property is not found default value depending on chip will be used.
|
|
oneOf:
|
|
- items:
|
|
- const: 1
|
|
- enum: [ 1, 3, 4, 6, 20, 8, 10, 16 ]
|
|
- items:
|
|
- const: 10
|
|
- const: 81
|
|
|
|
qcom,ratiometric:
|
|
type: boolean
|
|
description: |
|
|
Channel calibration type.
|
|
- For compatible property "qcom,spmi-vadc", if this property is
|
|
specified VADC will use the VDD reference (1.8V) and GND for
|
|
channel calibration. If property is not found, channel will be
|
|
calibrated with 0.625V and 1.25V reference channels, also
|
|
known as absolute calibration.
|
|
- For other compatible properties, if this property is specified
|
|
VADC will use the VDD reference (1.875V) and GND for channel
|
|
calibration. If property is not found, channel will be calibrated
|
|
with 0V and 1.25V reference channels, also known as absolute calibration.
|
|
|
|
qcom,hw-settle-time:
|
|
$ref: /schemas/types.yaml#/definitions/uint32
|
|
description: |
|
|
Time between AMUX getting configured and the ADC starting
|
|
conversion. The 'hw_settle_time' is an index used from valid values
|
|
and programmed in hardware to achieve the hardware settling delay.
|
|
|
|
qcom,avg-samples:
|
|
$ref: /schemas/types.yaml#/definitions/uint32
|
|
description: |
|
|
Number of samples to be used for measurement.
|
|
Averaging provides the option to obtain a single measurement
|
|
from the ADC that is an average of multiple samples. The value
|
|
selected is 2^(value).
|
|
|
|
required:
|
|
- reg
|
|
|
|
additionalProperties: true
|