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authorLinus Torvalds <torvalds@linux-foundation.org>2022-01-12 16:47:05 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2022-01-12 16:47:05 -0800
commit4eb766f64d120f0b80ec24282df789b7db2ff838 (patch)
treeaa10974bcdafef558dbd42b3a14c66264ec50b9d /Documentation/devicetree/bindings/i2c/i2c-mux-gpio.yaml
parentce990f1de0bc6ff3de43d385e0985efa980fba24 (diff)
parente623611b4d3f722b57ceeaf4368ac787837408e7 (diff)
Merge tag 'devicetree-for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull devicetree updates from Rob Herring: "Bindings: - DT schema conversions for Samsung clocks, RNG bindings, Qcom Command DB and rmtfs, gpio-restart, i2c-mux-gpio, i2c-mux-pinctl, Tegra I2C and BPMP, pwm-vibrator, Arm DSU, and Cadence macb - DT schema conversions for Broadcom platforms: interrupt controllers, STB GPIO, STB waketimer, STB reset, iProc MDIO mux, iProc PCIe, Cygnus PCIe PHY, PWM, USB BDC, BCM6328 LEDs, TMON, SYSTEMPORT, AMAC, Northstar 2 PCIe PHY, GENET, moca PHY, GISB arbiter, and SATA - Add binding schemas for Tegra210 EMC table, TI DC-DC converters, - Clean-ups of MDIO bus schemas to fix 'unevaluatedProperties' issues - More fixes due to 'unevaluatedProperties' enabling - Data type fixes and clean-ups of binding examples found in preparation to move to validating DTB files directly (instead of intermediate YAML representation. - Vendor prefixes for T-Head Semiconductor, OnePlus, and Sunplus - Add various new compatible strings DT core: - Silence a warning for overlapping reserved memory regions - Reimplement unittest overlay tracking - Fix stack frame size warning in unittest - Clean-ups of early FDT scanning functions - Fix handling of "linux,usable-memory-range" on EFI booted systems - Add support for 'fail' status on CPU nodes - Improve error message in of_phandle_iterator_next() - kbuild: Disable duplicate unit-address warnings for disabled nodes" * tag 'devicetree-for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (114 commits) dt-bindings: net: mdio: Drop resets/reset-names child properties dt-bindings: clock: samsung: convert S5Pv210 to dtschema dt-bindings: clock: samsung: convert Exynos5410 to dtschema dt-bindings: clock: samsung: convert Exynos5260 to dtschema dt-bindings: clock: samsung: extend Exynos7 bindings with UFS dt-bindings: clock: samsung: convert Exynos7 to dtschema dt-bindings: clock: samsung: convert Exynos5433 to dtschema dt-bindings: i2c: maxim,max96712: Add bindings for Maxim Integrated MAX96712 dt-bindings: iio: adi,ltc2983: Fix 64-bit property sizes dt-bindings: power: maxim,max17040: Fix incorrect type for 'maxim,rcomp' dt-bindings: interrupt-controller: arm,gic-v3: Fix 'interrupts' cell size in example dt-bindings: iio/magnetometer: yamaha,yas530: Fix invalid 'interrupts' in example dt-bindings: clock: imx5: Drop clock consumer node from example dt-bindings: Drop required 'interrupt-parent' dt-bindings: net: ti,dp83869: Drop value on boolean 'ti,max-output-impedance' dt-bindings: net: wireless: mt76: Fix 8-bit property sizes dt-bindings: PCI: snps,dw-pcie-ep: Drop conflicting 'max-functions' schema dt-bindings: i2c: st,stm32-i2c: Make each example a separate entry dt-bindings: net: stm32-dwmac: Make each example a separate entry dt-bindings: net: Cleanup MDIO node schemas ...
Diffstat (limited to 'Documentation/devicetree/bindings/i2c/i2c-mux-gpio.yaml')
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+# SPDX-License-Identifier: GPL-2.0-only
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/i2c/i2c-mux-gpio.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: GPIO-based I2C Bus Mux
+
+maintainers:
+ - Wolfram Sang <wsa@kernel.org>
+
+description: |
+ This binding describes an I2C bus multiplexer that uses GPIOs to route the I2C signals.
+
+ +-----+ +-----+
+ | dev | | dev |
+ +------------+ +-----+ +-----+
+ | SoC | | |
+ | | /--------+--------+
+ | +------+ | +------+ child bus A, on GPIO value set to 0
+ | | I2C |-|--| Mux |
+ | +------+ | +--+---+ child bus B, on GPIO value set to 1
+ | | | \----------+--------+--------+
+ | +------+ | | | | |
+ | | GPIO |-|-----+ +-----+ +-----+ +-----+
+ | +------+ | | dev | | dev | | dev |
+ +------------+ +-----+ +-----+ +-----+
+
+ For each I2C child node, an I2C child bus will be created. They will be numbered based on their
+ order in the device tree.
+
+ Whenever an access is made to a device on a child bus, the value set in the relevant node's reg
+ property will be output using the list of GPIOs, the first in the list holding the least-
+ significant value.
+
+ If an idle state is defined, using the idle-state (optional) property, whenever an access is not
+ being made to a device on a child bus, the GPIOs will be set according to the idle value.
+
+ If an idle state is not defined, the most recently used value will be left programmed into
+ hardware whenever no access is being made to a device on a child bus.
+
+properties:
+ compatible:
+ const: i2c-mux-gpio
+
+ i2c-parent:
+ description: phandle of the I2C bus that this multiplexer's master-side port is connected to
+ $ref: "/schemas/types.yaml#/definitions/phandle"
+
+ mux-gpios:
+ description: list of GPIOs used to control the muxer
+ minItems: 1
+ maxItems: 4 # Should be enough
+
+ idle-state:
+ description: Value to set the muxer to when idle. When no value is given, it defaults to the
+ last value used.
+ $ref: "/schemas/types.yaml#/definitions/uint32"
+
+allOf:
+ - $ref: i2c-mux.yaml
+
+unevaluatedProperties: false
+
+required:
+ - compatible
+ - i2c-parent
+ - mux-gpios
+
+examples:
+ - |
+ i2cmux {
+ compatible = "i2c-mux-gpio";
+ #address-cells = <1>;
+ #size-cells = <0>;
+ mux-gpios = <&gpio1 22 0>, <&gpio1 23 0>;
+ i2c-parent = <&i2c1>;
+
+ i2c@1 {
+ reg = <1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ ssd1307: oled@3c {
+ compatible = "solomon,ssd1307fb-i2c";
+ reg = <0x3c>;
+ pwms = <&pwm 4 3000>;
+ reset-gpios = <&gpio2 7 1>;
+ };
+ };
+
+ i2c@3 {
+ reg = <3>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ pca9555: pca9555@20 {
+ compatible = "nxp,pca9555";
+ gpio-controller;
+ #gpio-cells = <2>;
+ reg = <0x20>;
+ };
+ };
+ };