linux/Documentation/devicetree/bindings/phy/transmit-amplitude.yaml
Marek Behún 066c4b6ba0 dt-bindings: phy: Add tx-p2p-microvolt property binding
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,
which should be referenced by any binding that uses it.

Signed-off-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-11 11:21:34 +00:00

104 lines
2.3 KiB
YAML

# 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@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 ]
additionalProperties: true
examples:
- |
phy: phy {
#phy-cells = <1>;
tx-p2p-microvolt = <915000>, <1100000>, <1200000>;
tx-p2p-microvolt-names = "2500base-x", "usb-hs", "usb-ss";
};