1f544df78SEmmanuel Vadot# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) 2f544df78SEmmanuel Vadot%YAML 1.2 3f544df78SEmmanuel Vadot--- 4f544df78SEmmanuel Vadot$id: http://devicetree.org/schemas/iio/resolver/adi,ad2s90.yaml# 5f544df78SEmmanuel Vadot$schema: http://devicetree.org/meta-schemas/core.yaml# 6f544df78SEmmanuel Vadot 7f544df78SEmmanuel Vadottitle: Analog Devices AD2S90 Resolver-to-Digital Converter 8f544df78SEmmanuel Vadot 9f544df78SEmmanuel Vadotmaintainers: 10f544df78SEmmanuel Vadot - Matheus Tavares <matheus.bernardino@usp.br> 11f544df78SEmmanuel Vadot 12f544df78SEmmanuel Vadotdescription: | 13f544df78SEmmanuel Vadot Datasheet: https://www.analog.com/en/products/ad2s90.html 14f544df78SEmmanuel Vadot 15f544df78SEmmanuel Vadotproperties: 16f544df78SEmmanuel Vadot compatible: 17f544df78SEmmanuel Vadot const: adi,ad2s90 18f544df78SEmmanuel Vadot 19f544df78SEmmanuel Vadot reg: 20f544df78SEmmanuel Vadot maxItems: 1 21f544df78SEmmanuel Vadot 22f544df78SEmmanuel Vadot spi-max-frequency: 23f544df78SEmmanuel Vadot maximum: 830000 24f544df78SEmmanuel Vadot description: | 25f544df78SEmmanuel Vadot Chip's max frequency, as specified in its datasheet, is 2Mhz. But a 600ns 26f544df78SEmmanuel Vadot delay is expected between the application of a logic LO to CS and the 27f544df78SEmmanuel Vadot application of SCLK, as also specified. And since the delay is not 28f544df78SEmmanuel Vadot implemented in the spi code, to satisfy it, SCLK's period should be at 29f544df78SEmmanuel Vadot most 2 * 600ns, so the max frequency should be 1 / (2 * 6e-7), which gives 30f544df78SEmmanuel Vadot roughly 830000Hz. 31f544df78SEmmanuel Vadot 32f544df78SEmmanuel Vadot spi-cpol: true 33f544df78SEmmanuel Vadot 34f544df78SEmmanuel Vadot spi-cpha: true 35f544df78SEmmanuel Vadot 36f544df78SEmmanuel Vadotrequired: 37f544df78SEmmanuel Vadot - compatible 38f544df78SEmmanuel Vadot - reg 39f544df78SEmmanuel Vadot 40f544df78SEmmanuel Vadotdependencies: 41f544df78SEmmanuel Vadot spi-cpol: [ spi-cpha ] 42f544df78SEmmanuel Vadot spi-cpha: [ spi-cpol ] 43f544df78SEmmanuel Vadot 44c227958aSEmmanuel VadotallOf: 45c227958aSEmmanuel Vadot - $ref: /schemas/spi/spi-peripheral-props.yaml# 46c227958aSEmmanuel Vadot 47c227958aSEmmanuel VadotunevaluatedProperties: false 48c227958aSEmmanuel Vadot 49f544df78SEmmanuel Vadotexamples: 50f544df78SEmmanuel Vadot - | 51f544df78SEmmanuel Vadot spi { 52f544df78SEmmanuel Vadot #address-cells = <1>; 53f544df78SEmmanuel Vadot #size-cells = <0>; 54f544df78SEmmanuel Vadot 55f544df78SEmmanuel Vadot resolver@0 { 56f544df78SEmmanuel Vadot compatible = "adi,ad2s90"; 57f544df78SEmmanuel Vadot reg = <0>; 58f544df78SEmmanuel Vadot spi-max-frequency = <830000>; 59f544df78SEmmanuel Vadot spi-cpol; 60f544df78SEmmanuel Vadot spi-cpha; 61f544df78SEmmanuel Vadot }; 62f544df78SEmmanuel Vadot }; 63f544df78SEmmanuel Vadot... 64