linux-kernel - Re: [PATCH 2/2] phy: qcom-mipi-csi2: Add a CSI2 MIPI D-PHY driver

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <0a12879f-dc4a-47fb-87a0-ac4b8bcd4d75@linaro.org>
Date: Tue, 15 Jul 2025 01:13:01 +0100
From: Bryan O'Donoghue <bryan.odonoghue@...aro.org>
To: Vladimir Zapolskiy <vladimir.zapolskiy@...aro.org>,
 Vinod Koul <vkoul@...nel.org>, Kishon Vijay Abraham I <kishon@...nel.org>,
 Rob Herring <robh@...nel.org>, Krzysztof Kozlowski <krzk+dt@...nel.org>,
 Conor Dooley <conor+dt@...nel.org>
Cc: Bryan O'Donoghue <bod@...nel.org>, linux-arm-msm@...r.kernel.org,
 linux-phy@...ts.infradead.org, linux-media@...r.kernel.org,
 devicetree@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/2] phy: qcom-mipi-csi2: Add a CSI2 MIPI D-PHY driver

On 14/07/2025 16:30, Vladimir Zapolskiy wrote:
>>
>> I think that is genuinely something we should handle in camss-csid.c
>> maybe with some meta-data inside of the ports/endpoints..
>>
> 
> This is a CSIPHY property, a CSIPHY hardware configuration and a wiring
> of sensors to a CSIPHY. Where is the relation to CSID here? There is no.

All the PHY really needs to know is the # of lanes in aggregate, which 
physical lanes to map to which logical lanes and the pixel clock.

We should add additional support to the Kernel's D-PHY API parameters 
mechanism to support that physical-to-logical mapping but, that's not 
required for this series or for any currently know upstream user of CAMSS.

> Please share at least a device tree node description, which supports
> a connection of two sensors to a single CSIPHY, like it shall be done
> expectedly.
&camss {
     port@0 {
         csiphy0_lanes01_ep: endpoint0 {
             data-lanes = <0 1>;
             remote-endpoint = <&sensor0_ep>;
         };

         csiphy0_lanes23_ep: endpoint0 {
             data-lanes = <2 3>;
             remote-endpoint = <&sensor1_ep>;
         };
      };
};

&csiphy0 {
     status = "okay";

     vdda-0p8-supply = <&vreg_0p8>;
     vdda-1p2-supply = <&vreg_1p2>;
     phy-mode = <PHY_TYPE_DPHY>;
};

sensor0 {
     compatible = "manufacturer,sensor0";
     port {
         sensor0_ep: endpoint {
             data-lanes = <0 1>;
             remote-endpoint = <&csiphy0_lanes01_ep>;
         };
     };
};

sensor1 {
     compatible = "manufacturer,sensor1";
     port {
         sensor1_ep: endpoint {
             data-lanes = <0 1>;
             remote-endpoint = <&csiphy1_lanes23_ep>;
         };
     };
};

---
bod