[PATCH devicetree v2] dt-bindings: phy: Add `tx-p2p-microvolt` property binding
Rob Herring
robh at kernel.org
Tue Jan 18 19:07:09 PST 2022
On Wed, Jan 12, 2022 at 07:16:02PM +0100, Marek Behún wrote:
> Common PHYs and network PCSes often have the possibility to specify
> peak-to-peak voltage on the differential pair - the default voltage
> sometimes needs to be changed for a particular board.
>
> Add properties `tx-p2p-microvolt` and `tx-p2p-microvolt-names` for this
> purpose. The second property is needed to specify the mode for the
> corresponding voltage in the `tx-p2p-microvolt` property, if the voltage
> is to be used only for speficic mode. More voltage-mode pairs can be
> specified.
>
> Example usage with only one voltage (it will be used for all supported
> PHY modes, the `tx-p2p-microvolt-names` property is not needed in this
> case):
>
> tx-p2p-microvolt = <915000>;
>
> Example usage with voltages for multiple modes:
>
> tx-p2p-microvolt = <915000>, <1100000>, <1200000>;
> tx-p2p-microvolt-names = "2500base-x", "usb", "pcie";
>
> Add these properties into a separate file phy/transmit-amplitude.yaml,
> selecting it for validation if either of the `tx-p2p-microvolt`,
> `tx-p2p-microvolt-names` properties is set for a node.
>
> Signed-off-by: Marek Behún <kabel at kernel.org>
> ---
> .../bindings/phy/transmit-amplitude.yaml | 110 ++++++++++++++++++
> 1 file changed, 110 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/phy/transmit-amplitude.yaml
>
> diff --git a/Documentation/devicetree/bindings/phy/transmit-amplitude.yaml b/Documentation/devicetree/bindings/phy/transmit-amplitude.yaml
> new file mode 100644
> index 000000000000..90a491b75f61
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/phy/transmit-amplitude.yaml
> @@ -0,0 +1,110 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/phy/transmit-amplitude.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Common PHY and network PCS transmit amplitude property binding
> +
> +description:
> + Binding describing the peak-to-peak transmit amplitude for common PHYs
> + and network PCSes.
> +
> +maintainers:
> + - Marek Behún <kabel at kernel.org>
> +
> +properties:
> + tx-p2p-microvolt:
> + description:
> + Transmit amplitude voltages in microvolts, peak-to-peak. If this property
> + contains multiple values for various PHY modes, the
> + 'tx-p2p-microvolt-names' property must be provided and contain
> + corresponding mode names.
> +
> + tx-p2p-microvolt-names:
> + description: |
> + Names of the modes corresponding to voltages in the 'tx-p2p-microvolt'
> + property. Required only if multiple voltages are provided.
> +
> + If a value of 'default' is provided, the system should use it for any PHY
> + mode that is otherwise not defined here. If 'default' is not provided, the
> + system should use manufacturer default value.
> + minItems: 1
> + maxItems: 16
> + items:
> + enum:
> + - default
> +
> + # ethernet modes
> + - sgmii
> + - qsgmii
> + - xgmii
> + - 1000base-x
> + - 2500base-x
> + - 5gbase-r
> + - rxaui
> + - xaui
> + - 10gbase-kr
> + - usxgmii
> + - 10gbase-r
> + - 25gbase-r
> +
> + # PCIe modes
> + - pcie
> + - pcie1
> + - pcie2
> + - pcie3
> + - pcie4
> + - pcie5
> + - pcie6
> +
> + # USB modes
> + - usb
> + - usb-ls
> + - usb-fs
> + - usb-hs
> + - usb-ss
> + - usb-ss+
> + - usb-4
> +
> + # storage modes
> + - sata
> + - ufs-hs
> + - ufs-hs-a
> + - ufs-hs-b
> +
> + # display modes
> + - lvds
> + - dp
> + - dp-rbr
> + - dp-hbr
> + - dp-hbr2
> + - dp-hbr3
> + - dp-uhbr-10
> + - dp-uhbr-13.5
> + - dp-uhbr-20
> +
> + # camera modes
> + - mipi-dphy
> + - mipi-dphy-univ
> + - mipi-dphy-v2.5-univ
> +
> +dependencies:
> + tx-p2p-microvolt-names: [ tx-p2p-microvolt ]
> +
> +select:
This should be omitted and this schema should be referenced by any
binding that uses it. That is necessary so all properties get evaluated.
> + anyOf:
> + - required:
> + - 'tx-p2p-microvolt'
> + - required:
> + - 'tx-p2p-microvolt-names'
> +
> +additionalProperties: true
> +
> +examples:
> + - |
> + phy: phy {
> + #phy-cells = <1>;
> + tx-p2p-microvolt = <915000>, <1100000>, <1200000>;
> + tx-p2p-microvolt-names = "2500base-x", "usb-hs", "usb-ss";
> + };
> --
> 2.34.1
>
>
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