lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Tue, 28 Jan 2020 10:04:14 +1300 From: Chris Packham <chris.packham@...iedtelesis.co.nz> To: broonie@...nel.org, robh+dt@...nel.org, mark.rutland@....com Cc: linux-spi@...r.kernel.org, devicetree@...r.kernel.org, linux-kernel@...r.kernel.org, Chris Packham <chris.packham@...iedtelesis.co.nz> Subject: [PATCH v3 1/2] dt-bindings: spi: Document binding for generic SPI multiplexer 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@...iedtelesis.co.nz> --- Notes: Changes in v3: - make dt_binding_check clean (properly this time) Changes in v2: - update license - make dt_binding_check clean .../devicetree/bindings/spi/spi-mux.yaml | 89 +++++++++++++++++++ 1 file changed, 89 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..0ae692dc28b5 --- /dev/null +++ b/Documentation/devicetree/bindings/spi/spi-mux.yaml @@ -0,0 +1,89 @@ +# 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@...iedtelesis.co.nz> + +properties: + compatible: + const: spi-mux + + mux-controls: + maxItems: 1 + +required: + - compatible + - reg + - spi-max-frequency + - mux-controls + +examples: + - | + #include <dt-bindings/gpio/gpio.h> + mux: mux-controller { + compatible = "gpio-mux"; + #mux-control-cells = <0>; + + mux-gpios = <&gpio0 3 GPIO_ACTIVE_HIGH>; + }; + + spi { + #address-cells = <1>; + #size-cells = <0>; + spi@0 { + compatible = "spi-mux"; + reg = <0>; + #address-cells = <1>; + #size-cells = <0>; + spi-max-frequency = <100000000>; + + mux-controls = <&mux>; + + spi-flash@0 { + compatible = "jedec,spi-nor"; + reg = <0>; + #address-cells = <1>; + #size-cells = <0>; + spi-max-frequency = <40000000>; + }; + + spi-device@1 { + compatible = "lineartechnology,ltc2488"; + reg = <1>; + #address-cells = <1>; + #size-cells = <0>; + spi-max-frequency = <10000000>; + }; + }; + }; -- 2.25.0
Powered by blists - more mailing lists