1# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) 2%YAML 1.2 3--- 4$id: http://devicetree.org/schemas/spi/spi-peripheral-props.yaml# 5$schema: http://devicetree.org/meta-schemas/core.yaml# 6 7title: Peripheral-specific properties for a SPI bus. 8 9description: 10 Many SPI controllers need to add properties to peripheral devices. They could 11 be common properties like spi-max-frequency, spi-cs-high, etc. or they could 12 be controller specific like delay in clock or data lines, etc. These 13 properties need to be defined in the peripheral node because they are 14 per-peripheral and there can be multiple peripherals attached to a 15 controller. All those properties are listed here. The controller specific 16 properties should go in their own separate schema that should be referenced 17 from here. 18 19maintainers: 20 - Mark Brown <broonie@kernel.org> 21 22properties: 23 reg: 24 minItems: 1 25 maxItems: 256 26 items: 27 items: 28 - minimum: 0 29 maximum: 256 30 description: 31 Chip select used by the device. 32 33 spi-cs-high: 34 $ref: /schemas/types.yaml#/definitions/flag 35 description: 36 The device requires the chip select active high. 37 38 spi-lsb-first: 39 $ref: /schemas/types.yaml#/definitions/flag 40 description: 41 The device requires the LSB first mode. 42 43 spi-max-frequency: 44 $ref: /schemas/types.yaml#/definitions/uint32 45 description: 46 Maximum SPI clocking speed of the device in Hz. 47 48 spi-cs-setup-delay-ns: 49 description: 50 Delay in nanoseconds to be introduced by the controller after CS is 51 asserted. 52 53 spi-cs-hold-delay-ns: 54 description: 55 Delay in nanoseconds to be introduced by the controller before CS is 56 de-asserted. 57 58 spi-cs-inactive-delay-ns: 59 description: 60 Delay in nanoseconds to be introduced by the controller after CS is 61 de-asserted. 62 63 spi-rx-bus-width: 64 description: 65 Bus width to the SPI bus used for read transfers. 66 If 0 is provided, then no RX will be possible on this device. 67 $ref: /schemas/types.yaml#/definitions/uint32 68 enum: [0, 1, 2, 4, 8] 69 default: 1 70 71 spi-rx-delay-us: 72 description: 73 Delay, in microseconds, after a read transfer. 74 75 rx-sample-delay-ns: 76 description: SPI Rx sample delay offset, unit is nanoseconds. 77 The delay from the default sample time before the actual 78 sample of the rxd input signal occurs. 79 80 spi-tx-bus-width: 81 description: 82 Bus width to the SPI bus used for write transfers. 83 If 0 is provided, then no TX will be possible on this device. 84 $ref: /schemas/types.yaml#/definitions/uint32 85 enum: [0, 1, 2, 4, 8] 86 default: 1 87 88 spi-tx-delay-us: 89 description: 90 Delay, in microseconds, after a write transfer. 91 92 stacked-memories: 93 description: Several SPI memories can be wired in stacked mode. 94 This basically means that either a device features several chip 95 selects, or that different devices must be seen as a single 96 bigger chip. This basically doubles (or more) the total address 97 space with only a single additional wire, while still needing 98 to repeat the commands when crossing a chip boundary. The size of 99 each chip should be provided as members of the array. 100 $ref: /schemas/types.yaml#/definitions/uint64-array 101 minItems: 2 102 maxItems: 4 103 104 parallel-memories: 105 description: Several SPI memories can be wired in parallel mode. 106 The devices are physically on a different buses but will always 107 act synchronously as each data word is spread across the 108 different memories (eg. even bits are stored in one memory, odd 109 bits in the other). This basically doubles the address space and 110 the throughput while greatly complexifying the wiring because as 111 many busses as devices must be wired. The size of each chip should 112 be provided as members of the array. 113 $ref: /schemas/types.yaml#/definitions/uint64-array 114 minItems: 2 115 maxItems: 4 116 117 st,spi-midi-ns: 118 deprecated: true 119 description: | 120 Only for STM32H7, (Master Inter-Data Idleness) minimum time 121 delay in nanoseconds inserted between two consecutive data frames. 122 123# The controller specific properties go here. 124allOf: 125 - $ref: arm,pl022-peripheral-props.yaml# 126 - $ref: cdns,qspi-nor-peripheral-props.yaml# 127 - $ref: fsl,dspi-peripheral-props.yaml# 128 - $ref: samsung,spi-peripheral-props.yaml# 129 - $ref: nvidia,tegra210-quad-peripheral-props.yaml# 130 131additionalProperties: true 132