Re: [PATCH v3 2/5] dt-bindings: phy: rockchip,rk3588-mipi-dcphy: allow DSI and CSI consumers

[Krzysztof Kozlowski <krzk@kernel.org>]

On Mon, Aug 10, 2026 at 08:10:10PM +0800, Jason Yang wrote:
> The Samsung MIPI D-/C-PHY block on RK3588 drives a MIPI DSI
> transmitter and, on the same PHY, can receive from a MIPI CSI camera.
> Describing both as independent consumers of one PHY requires the
> devicetree to tell them apart.
> 
> Let the existing single cell also take PHY_TYPE_DSI or PHY_TYPE_CSI,
> selecting the PHY by the protocol the consumer speaks. PHY_TYPE_DPHY
> stays accepted and equivalent to PHY_TYPE_DSI so shipped device trees
> remain valid, and PHY_TYPE_CPHY keeps selecting a C-PHY transmitter.
> The receiver support added by this series is D-PHY only.
> 
> Signed-off-by: Jason Yang <jason98166@gmail.com>
> Assisted-by: Claude:claude-fable-5
> ---
>  .../devicetree/bindings/phy/rockchip,rk3588-mipi-dcphy.yaml   | 11 ++++++++---
>  1 file changed, 8 insertions(+), 3 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/phy/rockchip,rk3588-mipi-dcphy.yaml b/Documentation/devicetree/bindings/phy/rockchip,rk3588-mipi-dcphy.yaml
> index c8ff5ba22a86..1f7c2e2ddfc1 100644
> --- a/Documentation/devicetree/bindings/phy/rockchip,rk3588-mipi-dcphy.yaml
> +++ b/Documentation/devicetree/bindings/phy/rockchip,rk3588-mipi-dcphy.yaml
> @@ -22,9 +22,14 @@ properties:
>    "#phy-cells":
>      const: 1
>      description: |
> -      Argument is mode to operate in. Supported modes are:
> -        - PHY_TYPE_DPHY
> -        - PHY_TYPE_CPHY
> +      The block contains a MIPI transmitter and a MIPI receiver, which
> +      can be referenced independently. The argument selects one of
> +      them:
> +        - PHY_TYPE_DSI: the transmitter, for a MIPI DSI host
> +        - PHY_TYPE_CSI: the receiver, for a MIPI CSI-2 host
> +        - PHY_TYPE_DPHY: the transmitter in D-PHY mode; equivalent to
> +          PHY_TYPE_DSI and kept for existing device trees
> +        - PHY_TYPE_CPHY: the transmitter in C-PHY mode

So PHY_TYPE_DSI is the same as PHY_TYPE_DPHY. Why doing this change?
Commit msg did not tell me why we need equivalent code.

Best regards,
Krzysztof