cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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i2c-mux-gpmux.yaml (3702B)

      1# SPDX-License-Identifier: GPL-2.0
      2%YAML 1.2
      3---
      4$id: http://devicetree.org/schemas/i2c/i2c-mux-gpmux.yaml#
      5$schema: http://devicetree.org/meta-schemas/core.yaml#
      6
      7title: General Purpose I2C Bus Mux
      8
      9maintainers:
     10  - Peter Rosin <peda@axentia.se>
     11
     12description: |+
     13  This binding describes an I2C bus multiplexer that uses a mux controller
     14  from the mux subsystem to route the I2C signals.
     15
     16                                    .-----.  .-----.
     17                                    | dev |  | dev |
     18      .------------.                '-----'  '-----'
     19      | SoC        |                   |        |
     20      |            |          .--------+--------'
     21      |   .------. |  .------+    child bus A, on MUX value set to 0
     22      |   | I2C  |-|--| Mux  |
     23      |   '------' |  '--+---+    child bus B, on MUX value set to 1
     24      |   .------. |     |    '----------+--------+--------.
     25      |   | MUX- | |     |               |        |        |
     26      |   | Ctrl |-|-----+            .-----.  .-----.  .-----.
     27      |   '------' |                  | dev |  | dev |  | dev |
     28      '------------'                  '-----'  '-----'  '-----'
     29
     30
     31allOf:
     32  - $ref: /schemas/i2c/i2c-mux.yaml#
     33
     34properties:
     35  compatible:
     36    const: i2c-mux
     37
     38  i2c-parent:
     39    $ref: /schemas/types.yaml#/definitions/phandle
     40    description:
     41      The phandle of the I2C bus that this multiplexer's master-side port is
     42      connected to.
     43
     44  mux-controls:
     45    maxItems: 1
     46    description:
     47      The mux-controller states are the I2C sub-bus numbers.
     48
     49  mux-locked:
     50    type: boolean
     51    description: |
     52      Explicitly allow unrelated I2C transactions on the parent I2C adapter at
     53      these times:
     54       - during setup of the multiplexer
     55       - between setup of the multiplexer and the child bus I2C transaction
     56       - between the child bus I2C transaction and releasing of the multiplexer
     57       - during releasing of the multiplexer
     58
     59      However, I2C transactions to devices behind all I2C multiplexers connected
     60      to the same parent adapter that this multiplexer is connected to are blocked
     61      for the full duration of the complete multiplexed I2C transaction (i.e.
     62      including the times covered by the above list).
     63      If mux-locked is not present, the multiplexer is assumed to be parent-locked.
     64      This means that no unrelated I2C transactions are allowed on the parent I2C
     65      adapter for the complete multiplexed I2C transaction.
     66      The properties of mux-locked and parent-locked multiplexers are discussed
     67      in more detail in Documentation/i2c/i2c-topology.rst.
     68
     69required:
     70  - compatible
     71  - i2c-parent
     72  - mux-controls
     73
     74unevaluatedProperties: false
     75
     76examples:
     77  - |
     78    #include <dt-bindings/gpio/gpio.h>
     79    mux: mux-controller {
     80        compatible = "gpio-mux";
     81        #mux-control-cells = <0>;
     82
     83        mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
     84                    <&pioA 1 GPIO_ACTIVE_HIGH>;
     85    };
     86
     87    i2c-mux {
     88        compatible = "i2c-mux";
     89        mux-locked;
     90        i2c-parent = <&i2c1>;
     91
     92        mux-controls = <&mux>;
     93
     94        #address-cells = <1>;
     95        #size-cells = <0>;
     96
     97        i2c@1 {
     98            reg = <1>;
     99            #address-cells = <1>;
    100            #size-cells = <0>;
    101
    102            gpio@20 {
    103                compatible = "nxp,pca9555";
    104                gpio-controller;
    105                #gpio-cells = <2>;
    106                reg = <0x20>;
    107            };
    108        };
    109
    110        i2c@3 {
    111            reg = <3>;
    112            #address-cells = <1>;
    113            #size-cells = <0>;
    114
    115            gpio@20 {
    116                compatible = "nxp,pca9555";
    117                gpio-controller;
    118                #gpio-cells = <2>;
    119                reg = <0x20>;
    120            };
    121        };
    122    };
    123...