Documentation/devicetree/bindings/net/mdio.yaml

   1 # SPDX-License-Identifier: GPL-2.0
   2 %YAML 1.2
   3 ---
   4 $id: http://devicetree.org/schemas/net/mdio.yaml#
   5 $schema: http://devicetree.org/meta-schemas/core.yaml#
   6
   7 title: MDIO Bus Generic Binding
   8
   9 maintainers:
  10   - Andrew Lunn <andrew@lunn.ch>
  11   - Florian Fainelli <f.fainelli@gmail.com>
  12   - Heiner Kallweit <hkallweit1@gmail.com>
  13
  14 description:
  15   These are generic properties that can apply to any MDIO bus. Any
  16   MDIO bus must have a list of child nodes, one per device on the
  17   bus. These should follow the generic ethernet-phy.yaml document, or
  18   a device specific binding document.
  19
  20 properties:
  21   $nodename:
  22     pattern: "^mdio(@.*)?"
  23
  24   "#address-cells":
  25     const: 1
  26
  27   "#size-cells":
  28     const: 0
  29
  30   reset-gpios:
  31     maxItems: 1
  32     description:
  33       The phandle and specifier for the GPIO that controls the RESET
  34       lines of all devices on that MDIO bus.
  35
  36   reset-delay-us:
  37     description:
  38       RESET pulse width in microseconds. It applies to all MDIO devices
  39       and must therefore be appropriately determined based on all devices
  40       requirements (maximum value of all per-device RESET pulse widths).
  41
  42   reset-post-delay-us:
  43     description:
  44       Delay after reset deassert in microseconds. It applies to all MDIO
  45       devices and it's determined by how fast all devices are ready for
  46       communication. This delay happens just before e.g. Ethernet PHY
  47       type ID auto detection.
  48
  49   clock-frequency:
  50     description:
  51       Desired MDIO bus clock frequency in Hz. Values greater than IEEE 802.3
  52       defined 2.5MHz should only be used when all devices on the bus support
  53       the given clock speed.
  54
  55   suppress-preamble:
  56     description:
  57       The 32 bit preamble should be suppressed. In order for this to
  58       work, all devices on the bus must support suppressed preamble.
  59     type: boolean
  60
  61 patternProperties:
  62   "^ethernet-phy@[0-9a-f]+$":
  63     type: object
  64
  65     properties:
  66       reg:
  67         minimum: 0
  68         maximum: 31
  69         description:
  70           The ID number for the device.
  71
  72       broken-turn-around:
  73         $ref: /schemas/types.yaml#/definitions/flag
  74         description:
  75           If set, indicates the MDIO device does not correctly release
  76           the turn around line low at end of the control phase of the
  77           MDIO transaction.
  78
  79       resets:
  80         maxItems: 1
  81
  82       reset-names:
  83         const: phy
  84
  85       reset-gpios:
  86         maxItems: 1
  87         description:
  88           The GPIO phandle and specifier for the MDIO reset signal.
  89
  90       reset-assert-us:
  91         description:
  92           Delay after the reset was asserted in microseconds. If this
  93           property is missing the delay will be skipped.
  94
  95       reset-deassert-us:
  96         description:
  97           Delay after the reset was deasserted in microseconds. If
  98           this property is missing the delay will be skipped.
  99
 100     required:
 101       - reg
 102
 103 additionalProperties: true
 104
 105 examples:
 106   - |
 107     davinci_mdio: mdio@5c030000 {
 108         reg = <0x5c030000 0x1000>;
 109         #address-cells = <1>;
 110         #size-cells = <0>;
 111
 112         reset-gpios = <&gpio2 5 1>;
 113         reset-delay-us = <2>;
 114
 115         ethphy0: ethernet-phy@1 {
 116             reg = <1>;
 117         };
 118
 119         ethphy1: ethernet-phy@3 {
 120             reg = <3>;
 121         };
 122     };