Bindings/clock/google,gs101-clock.yaml

   1 # SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
   2 %YAML 1.2
   3 ---
   4 $id: http://devicetree.org/schemas/clock/google,gs101-clock.yaml#
   5 $schema: http://devicetree.org/meta-schemas/core.yaml#
   6
   7 title: Google GS101 SoC clock controller
   8
   9 maintainers:
  10   - Peter Griffin <peter.griffin@linaro.org>
  11
  12 description: |
  13   Google GS101 clock controller is comprised of several CMU units, generating
  14   clocks for different domains. Those CMU units are modeled as separate device
  15   tree nodes, and might depend on each other. The root clock in that clock tree
  16   is OSCCLK (24.576 MHz). That external clock must be defined as a fixed-rate
  17   clock in dts.
  18
  19   CMU_TOP is a top-level CMU, where all base clocks are prepared using PLLs and
  20   dividers; all other leaf clocks (other CMUs) are usually derived from CMU_TOP.
  21
  22   Each clock is assigned an identifier and client nodes can use this identifier
  23   to specify the clock which they consume. All clocks available for usage
  24   in clock consumer nodes are defined as preprocessor macros in
  25   'dt-bindings/clock/gs101.h' header.
  26
  27 properties:
  28   compatible:
  29     enum:
  30       - google,gs101-cmu-top
  31       - google,gs101-cmu-apm
  32       - google,gs101-cmu-misc
  33
  34   clocks:
  35     minItems: 1
  36     maxItems: 2
  37
  38   clock-names:
  39     minItems: 1
  40     maxItems: 2
  41
  42   "#clock-cells":
  43     const: 1
  44
  45   reg:
  46     maxItems: 1
  47
  48 required:
  49   - compatible
  50   - "#clock-cells"
  51   - clocks
  52   - clock-names
  53   - reg
  54
  55 allOf:
  56   - if:
  57       properties:
  58         compatible:
  59           contains:
  60             enum:
  61               - google,gs101-cmu-top
  62               - google,gs101-cmu-apm
  63     then:
  64       properties:
  65         clocks:
  66           items:
  67             - description: External reference clock (24.576 MHz)
  68
  69         clock-names:
  70           items:
  71             - const: oscclk
  72
  73   - if:
  74       properties:
  75         compatible:
  76           contains:
  77             const: google,gs101-cmu-misc
  78
  79     then:
  80       properties:
  81         clocks:
  82           items:
  83             - description: Misc bus clock (from CMU_TOP)
  84             - description: Misc sss clock (from CMU_TOP)
  85
  86         clock-names:
  87           items:
  88             - const: bus
  89             - const: sss
  90
  91 additionalProperties: false
  92
  93 examples:
  94   # Clock controller node for CMU_TOP
  95   - |
  96     #include <dt-bindings/clock/google,gs101.h>
  97
  98     cmu_top: clock-controller@1e080000 {
  99         compatible = "google,gs101-cmu-top";
 100         reg = <0x1e080000 0x8000>;
 101         #clock-cells = <1>;
 102         clocks = <&ext_24_5m>;
 103         clock-names = "oscclk";
 104     };
 105
 106 ...