# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) %YAML 1.2 --- $id: http://devicetree.org/schemas/spi/spi-peripheral-props.yaml# $schema: http://devicetree.org/meta-schemas/core.yaml# title: Peripheral-specific properties for a SPI bus. description: Many SPI controllers need to add properties to peripheral devices. They could be common properties like spi-max-frequency, spi-cpha, etc. or they could be controller specific like delay in clock or data lines, etc. These properties need to be defined in the peripheral node because they are per-peripheral and there can be multiple peripherals attached to a controller. All those properties are listed here. The controller specific properties should go in their own separate schema that should be referenced from here. maintainers: - Mark Brown properties: reg: minItems: 1 maxItems: 256 items: items: - minimum: 0 maximum: 256 description: Chip select used by the device. spi-cs-high: $ref: /schemas/types.yaml#/definitions/flag description: The device requires the chip select active high. spi-lsb-first: $ref: /schemas/types.yaml#/definitions/flag description: The device requires the LSB first mode. spi-max-frequency: $ref: /schemas/types.yaml#/definitions/uint32 description: Maximum SPI clocking speed of the device in Hz. spi-cs-setup-delay-ns: description: Delay in nanoseconds to be introduced by the controller after CS is asserted. spi-cs-hold-delay-ns: description: Delay in nanoseconds to be introduced by the controller before CS is de-asserted. spi-cs-inactive-delay-ns: description: Delay in nanoseconds to be introduced by the controller after CS is de-asserted. spi-rx-bus-width: description: Bus width to the SPI bus used for read transfers. If 0 is provided, then no RX will be possible on this device. $ref: /schemas/types.yaml#/definitions/uint32 enum: [0, 1, 2, 4, 8] default: 1 spi-rx-delay-us: description: Delay, in microseconds, after a read transfer. rx-sample-delay-ns: description: SPI Rx sample delay offset, unit is nanoseconds. The delay from the default sample time before the actual sample of the rxd input signal occurs. spi-tx-bus-width: description: Bus width to the SPI bus used for write transfers. If 0 is provided, then no TX will be possible on this device. $ref: /schemas/types.yaml#/definitions/uint32 enum: [0, 1, 2, 4, 8] default: 1 spi-tx-delay-us: description: Delay, in microseconds, after a write transfer. stacked-memories: description: Several SPI memories can be wired in stacked mode. This basically means that either a device features several chip selects, or that different devices must be seen as a single bigger chip. This basically doubles (or more) the total address space with only a single additional wire, while still needing to repeat the commands when crossing a chip boundary. The size of each chip should be provided as members of the array. $ref: /schemas/types.yaml#/definitions/uint64-array minItems: 2 maxItems: 4 parallel-memories: description: Several SPI memories can be wired in parallel mode. The devices are physically on a different buses but will always act synchronously as each data word is spread across the different memories (eg. even bits are stored in one memory, odd bits in the other). This basically doubles the address space and the throughput while greatly complexifying the wiring because as many busses as devices must be wired. The size of each chip should be provided as members of the array. $ref: /schemas/types.yaml#/definitions/uint64-array minItems: 2 maxItems: 4 st,spi-midi-ns: description: | Only for STM32H7, (Master Inter-Data Idleness) minimum time delay in nanoseconds inserted between two consecutive data frames. # The controller specific properties go here. allOf: - $ref: arm,pl022-peripheral-props.yaml# - $ref: cdns,qspi-nor-peripheral-props.yaml# - $ref: samsung,spi-peripheral-props.yaml# - $ref: nvidia,tegra210-quad-peripheral-props.yaml# additionalProperties: true