On Wed, Jan 22, 2020 at 7:24 PM Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx> wrote: > > Add binding documentation for the spi-mux driver. This allows a generic > multiplexer to be used to provide access to multiple SPI devices. > > Signed-off-by: Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx> > --- > > Notes: > Changes in v2: > - update license > - make dt_binding_check clean Sure about that? > > .../devicetree/bindings/spi/spi-mux.yaml | 84 +++++++++++++++++++ > 1 file changed, 84 insertions(+) > create mode 100644 Documentation/devicetree/bindings/spi/spi-mux.yaml > > diff --git a/Documentation/devicetree/bindings/spi/spi-mux.yaml b/Documentation/devicetree/bindings/spi/spi-mux.yaml > new file mode 100644 > index 000000000000..4bdb31e2257e > --- /dev/null > +++ b/Documentation/devicetree/bindings/spi/spi-mux.yaml > @@ -0,0 +1,84 @@ > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) > +%YAML 1.2 > +--- > +$id: http://devicetree.org/schemas/spi/spi-mux.yaml# > +$schema: http://devicetree.org/meta-schemas/core.yaml# > + > +title: Generic SPI Multiplexer > + > +description: | > + This binding describes a SPI bus multiplexer to route the SPI chip select > + signals. This can be used when you need more devices than the SPI controller > + has chip selects available. An example setup is shown in ASCII art; the actual > + setting of the multiplexer to a channel needs to be done by a specific SPI mux > + driver. > + > + MOSI /--------------------------------+--------+--------+--------\ > + MISO |/------------------------------+|-------+|-------+|-------\| > + SCL ||/----------------------------+||------+||------+||------\|| > + ||| ||| ||| ||| ||| > + +------------+ ||| ||| ||| ||| > + | SoC ||| | +-+++-+ +-+++-+ +-+++-+ +-+++-+ > + | ||| | | dev | | dev | | dev | | dev | > + | +--+++-+ | CS-X +------+\ +--+--+ +--+--+ +--+--+ +--+--+ > + | | SPI +-|-------+ Mux |\\ CS-0 | | | | > + | +------+ | +--+---+\\\-------/ CS-1 | | | > + | | | \\\----------------/ CS-2 | | > + | +------+ | | \\-------------------------/ CS-3 | > + | | ? +-|----------/ \----------------------------------/ > + | +------+ | > + +------------+ > + > +allOf: > + - $ref: "/schemas/spi/spi-controller.yaml#" > + > +maintainers: > + - Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx> > + > +properties: > + compatible: > + const: spi-mux > + > + mux-controls: > + maxItems: 1 > + > +required: > + - compatible > + - reg > + - spi-max-frequency > + - mux-controls > + > +examples: > + - | > + mux: mux-controller { > + compatible = "gpio-mux"; > + #mux-control-cells = <0>; > + > + mux-gpios = <&gpio0 3 GPIO_ACTIVE_HIGH>; > + }; > + > + spi { > + spi-mux@0 { > + compatible = "spi-mux"; > + #address-cells = <1>; > + #size-cells = <0>; > + reg = <0>; > + spi-max-frequency = <100000000>; > + > + mux-controls = <&mux> Missing semicolon. > + > + spi-flash@0 { > + compatible = "jedec,spi-nor"; > + #address-cells = <1>; > + #size-cells = <1>; > + reg = <0>; > + spi-max-frequency = <40000000>; > + }; > + > + spi-device@1 { > + compatible = "lineartechnology,ltc2488"; > + reg = <1>; > + spi-max-frequency = <10000000>; > + }; > + }; > + }; > -- > 2.25.0 >
