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-rw-r--r--Documentation/devicetree/bindings/spi/spi-bus.txt83
1 files changed, 1 insertions, 82 deletions
diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt
index 296015e3c632..e07783505498 100644
--- a/Documentation/devicetree/bindings/spi/spi-bus.txt
+++ b/Documentation/devicetree/bindings/spi/spi-bus.txt
@@ -1,82 +1 @@
-SPI (Serial Peripheral Interface) busses
-
-SPI busses can be described with a node for the SPI master device
-and a set of child nodes for each SPI slave on the bus. For this
-discussion, it is assumed that the system's SPI controller is in
-SPI master mode. This binding does not describe SPI controllers
-in slave mode.
-
-The SPI master node requires the following properties:
-- #address-cells - number of cells required to define a chip select
- address on the SPI bus.
-- #size-cells - should be zero.
-- compatible - name of SPI bus controller following generic names
- recommended practice.
-- cs-gpios - (optional) gpios chip select.
-No other properties are required in the SPI bus node. It is assumed
-that a driver for an SPI bus device will understand that it is an SPI bus.
-However, the binding does not attempt to define the specific method for
-assigning chip select numbers. Since SPI chip select configuration is
-flexible and non-standardized, it is left out of this binding with the
-assumption that board specific platform code will be used to manage
-chip selects. Individual drivers can define additional properties to
-support describing the chip select layout.
-
-Optional property:
-- num-cs : total number of chipselects
-
-If cs-gpios is used the number of chip select will automatically increased
-with max(cs-gpios > hw cs)
-
-So if for example the controller has 2 CS lines, and the cs-gpios
-property looks like this:
-
-cs-gpios = <&gpio1 0 0> <0> <&gpio1 1 0> <&gpio1 2 0>;
-
-Then it should be configured so that num_chipselect = 4 with the
-following mapping:
-
-cs0 : &gpio1 0 0
-cs1 : native
-cs2 : &gpio1 1 0
-cs3 : &gpio1 2 0
-
-SPI slave nodes must be children of the SPI master node and can
-contain the following properties.
-- reg - (required) chip select address of device.
-- compatible - (required) name of SPI device following generic names
- recommended practice
-- spi-max-frequency - (required) Maximum SPI clocking speed of device in Hz
-- spi-cpol - (optional) Empty property indicating device requires
- inverse clock polarity (CPOL) mode
-- spi-cpha - (optional) Empty property indicating device requires
- shifted clock phase (CPHA) mode
-- spi-cs-high - (optional) Empty property indicating device requires
- chip select active high
-- spi-3wire - (optional) Empty property indicating device requires
- 3-wire mode.
-
-If a gpio chipselect is used for the SPI slave the gpio number will be passed
-via the cs_gpio
-
-SPI example for an MPC5200 SPI bus:
- spi@f00 {
- #address-cells = <1>;
- #size-cells = <0>;
- compatible = "fsl,mpc5200b-spi","fsl,mpc5200-spi";
- reg = <0xf00 0x20>;
- interrupts = <2 13 0 2 14 0>;
- interrupt-parent = <&mpc5200_pic>;
-
- ethernet-switch@0 {
- compatible = "micrel,ks8995m";
- spi-max-frequency = <1000000>;
- reg = <0>;
- };
-
- codec@1 {
- compatible = "ti,tlv320aic26";
- spi-max-frequency = <100000>;
- reg = <1>;
- };
- };
+This file has moved to spi-controller.yaml.