[PATCH v3 1/5] dt-bindings: phy: Add PHY_TYPE_DSI and PHY_TYPE_CSI definitions
Krzysztof Kozlowski
krzk at kernel.org
Thu Aug 13 00:59:32 PDT 2026
On Thu, Aug 13, 2026 at 12:33:52PM +0800, 楊智成 wrote:
> Hi Sebastian,
>
> Thanks for the review.
>
> > Your new binding is lacking too. If you select <&mipidcphy0 PHY_TYPE_CSI>
> > you defined the direction of the PHY, but will it operate in C-PHY or in
> > D-PHY mode?
>
> You are right, and I am sorry - this is a regression I introduced in v3.
>
> v2 already described these as two separate cells: the first selected the
> electrical layer, and the second selected the direction. Michael Riesch
> suggested using the generic PHY_TYPE_DSI/PHY_TYPE_CSI constants for the
> second cell instead of the Rockchip-private RK_DCPHY_DIR_* constants [1],
> and Vinod Koul agreed [2].
>
> In v3, while making that change, I also mistakenly collapsed the two cells
> into one. That is what lost the electrical-layer information you pointed
> out.
>
> For v4, I will go back to the v2 layout and only rename the second cell.
> This keeps the two dimensions separate, with each cell describing one
> thing:
>
> /* MIPI DSI host - the transmitter */
> phys = <&mipidcphy0 PHY_TYPE_DPHY PHY_TYPE_DSI>;
>
> /* MIPI CSI-2 host - the receiver */
> phys = <&mipidcphy0 PHY_TYPE_DPHY PHY_TYPE_CSI>;
>
> The same applies to C-PHY, so the binding can express all four combinations
> without any further changes:
>
> phys = <&mipidcphy0 PHY_TYPE_CPHY PHY_TYPE_DSI>;
> phys = <&mipidcphy0 PHY_TYPE_CPHY PHY_TYPE_CSI>;
>
> The driver accepts all four combinations at phy_get() time and returns
> -EOPNOTSUPP from power_on() for the C-PHY combinations, as it did before
> this series. Boards that only wire up the transmitter keep
> '#phy-cells = <1>', so the existing in-tree device trees remain unaffected.
>
> Before sending v4, I will go through the code and commit messages again,
> so that the reasoning above is captured in the commits themselves rather
> than only in this thread. I will also re-test the series on the board.
What is with this practice (third posting I see this week) of pasting
as reply prompts/tasks for AI?
All this is just wrong approach and your patches will be ignored if you
act as a proxy and keep playing with us that way.
Best regards,
Krzysztof
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