Lines Matching +full:spi +full:- +full:max +full:- +full:frequency
1 # SPDX-License-Identifier: GPL-2.0
3 ---
4 $id: http://devicetree.org/schemas/spi/spi-controller.yaml#
5 $schema: http://devicetree.org/meta-schemas/core.yaml#
7 title: SPI Controller Common Properties
10 - Mark Brown <[email protected]>
13 SPI busses can be described with a node for the SPI controller device
14 and a set of child nodes for each SPI slave on the bus. The system SPI
15 controller may be described for use in SPI master mode or in SPI slave mode,
20 pattern: "^spi(@.*|-([0-9]|[1-9][0-9]+))?$"
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>;
49 cs-gpio with the optional spi-cs-high flag for SPI slaves.
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 |
68 because ACTIVE_LOW is overridden by spi-cs-high.
70 spi-cs-high + ACTIVE_HIGH.
72 The simplest way to obtain an active-high CS signal is to configure the
73 controller's cs-gpio property with the ACTIVE_HIGH flag and set the
74 peripheral's spi-cs-high property. See example below for a better
77 fifo-depth:
82 rx-fifo-depth:
87 tx-fifo-depth:
92 num-cs:
97 spi-slave:
100 The SPI controller acts as a slave, instead of a master.
108 Compatible of the SPI device.
111 - compatible
114 "^.*@[0-9a-f]+$":
116 $ref: spi-peripheral-props.yaml
120 spi-3wire:
123 The device requires 3-wire mode.
125 spi-cpha:
130 spi-cpol:
136 - compatible
137 - reg
140 rx-fifo-depth: [ tx-fifo-depth ]
141 tx-fifo-depth: [ rx-fifo-depth ]
144 - if:
147 - spi-slave
150 "#address-cells":
154 "#address-cells":
156 - not:
158 - fifo-depth
159 - rx-fifo-depth
160 - not:
162 - fifo-depth
163 - tx-fifo-depth
168 - |
169 spi@80010000 {
170 #address-cells = <1>;
171 #size-cells = <0>;
172 compatible = "fsl,imx28-spi";
176 dma-names = "rx-tx";
180 spi-max-frequency = <1000000>;
186 spi-max-frequency = <100000>;
191 compatible = "jedec,spi-nor";
192 spi-max-frequency = <50000000>;
194 stacked-memories = /bits/ 64 <0x10000000 0x10000000>;
198 - |
199 #include <dt-bindings/gpio/gpio.h>
201 spi@20204000 {
202 #address-cells = <1>;
203 #size-cells = <0>;
204 compatible = "brcm,bcm2835-spi";
208 cs-gpios = <&gpio 8 GPIO_ACTIVE_HIGH>;
212 spi-max-frequency = <1000000>;
214 spi-cs-high;