Re: [PATCH v6 2/5] dt-bindings: media: Add qcom,x1e80100-camss

From: Bryan O'Donoghue
Date: Thu Apr 24 2025 - 12:14:35 EST


On 24/04/2025 16:54, Krzysztof Kozlowski wrote:
On 24/04/2025 12:17, Bryan O'Donoghue wrote:
On 24/04/2025 11:07, Krzysztof Kozlowski wrote:
On 24/04/2025 11:34, Bryan O'Donoghue wrote:
On 24/04/2025 07:40, Krzysztof Kozlowski wrote:
+ vdd-csiphy-0p8-supply:
Same comment as other series on the lists - this is wrong name. There
are no pins named like this and all existing bindings use different name.

The existing bindings are unfortunately not granular enough.

I'll post s series to capture pin-names per the SoC pinout shortly.
How are the pins/supplies actually called?

Best regards,
Krzysztof

I don't think strictly algning to pin-names is what we want.

Here are the input pins

VDD_A_CSI_0_1_1P2
VDD_A_CSI_2_4_1P2
VDD_A_CSI_0_1_0P9
VDD_A_CSI_2_4_0P9

I think the right way to represent this

yaml:
csiphy0-1p2-supply
csiphy1-1p2-supply

But there is no separate supply for csiphy0 and csiphy1. Such split
feels fine if you have separate CSI phy device nodes, which now I wonder
- where are they?

Best regards,
Krzysztof

The main hardware argument for it is probably these PHYs do live inside of the TITAN_TOP_GDSC power-domain, which is the same collapsible power-domain that all of the other CAMSS components live inside of.

As I recall we had a four way - albeit long discussion on this in Dublin, you, me, Vlad and Neil and my memory was we would implement multiple rails in the existing CAMSS PHY structure and then look at how to model the PHYs differently in DTS.

The Test Pattern Generators - TPGs would then also fit into this new model for the PHYs.

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bod