bindings/spi/spi-controller.yaml

1 # SPDX-License-Identifier: GPL-2.0
3 ---
4 $id: http://devicetree.org/schemas/spi/spi-controller.yaml#
5 $schema: http://devicetree.org/meta-schemas/core.yaml#
7 title: SPI Controller Common Properties
10   - Mark Brown <broonie@kernel.org>
13   SPI busses can be described with a node for the SPI controller device
14   and a set of child nodes for each SPI slave on the bus. The system SPI
15   controller may be described for use in SPI master mode or in SPI slave mode,
20     pattern: "^spi(@.*|-([0-9]|[1-9][0-9]+))?$"
22   "#address-cells":
25   "#size-cells":
28   cs-gpios:
32       increased automatically with max(cs-gpios, hardware chip selects).
35       cs-gpios looks like this
36         cs-gpios = <&gpio1 0 0>, <0>, <&gpio1 1 0>, <&gpio1 2 0>;
45       The second flag of a gpio descriptor can be GPIO_ACTIVE_HIGH (0)
49       cs-gpio with the optional spi-cs-high flag for SPI slaves.
52       driven (not considering potential gpio inversions by pinmux):
54       device node     | cs-gpio       | CS pin state active | Note
56       spi-cs-high     | -             | H                   |
57       -               | -             | L                   |
58       spi-cs-high     | ACTIVE_HIGH   | H                   |
59       -               | ACTIVE_HIGH   | L                   | 1
60       spi-cs-high     | ACTIVE_LOW    | H                   | 2
61       -               | ACTIVE_LOW    | L                   |
65          Here it would be wise to avoid and define the gpio as
68          because ACTIVE_LOW is overridden by spi-cs-high.
70          spi-cs-high + ACTIVE_HIGH.
72   fifo-depth:
77   rx-fifo-depth:
82   tx-fifo-depth:
87   num-cs:
92   spi-slave:
95       The SPI controller acts as a slave, instead of a master.
103           Compatible of the SPI device.
106       - compatible
109   "^.*@[0-9a-f]+$":
111     $ref: spi-peripheral-props.yaml
115       spi-3wire:
118           The device requires 3-wire mode.
120       spi-cpha:
125       spi-cpol:
131       - compatible
132       - reg
135   rx-fifo-depth: [ tx-fifo-depth ]
136   tx-fifo-depth: [ rx-fifo-depth ]
139   - if:
142           - spi-slave
145         "#address-cells":
149         "#address-cells":
151   - not:
153         - fifo-depth
154         - rx-fifo-depth
155   - not:
157         - fifo-depth
158         - tx-fifo-depth
163   - |
164     spi@80010000 {
165         #address-cells = <1>;
166         #size-cells = <0>;
167         compatible = "fsl,imx28-spi";
171         dma-names = "rx-tx";
175             spi-max-frequency = <1000000>;
181             spi-max-frequency = <100000>;
186             compatible = "jedec,spi-nor";
187             spi-max-frequency = <50000000>;
189             stacked-memories = /bits/ 64 <0x10000000 0x10000000>;