linux-kernel - Re: [PATCH v2 8/9] media: dt-bindings: Add Intel Displayport RX IP

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]

Date: Mon, 26 Feb 2024 13:06:29 +0100
From: Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>
To: Paweł Anikiel <panikiel@...gle.com>
Cc: airlied@...il.com, akpm@...ux-foundation.org, conor+dt@...nel.org,
 daniel@...ll.ch, dinguyen@...nel.org, hverkuil-cisco@...all.nl,
 krzysztof.kozlowski+dt@...aro.org, maarten.lankhorst@...ux.intel.com,
 mchehab@...nel.org, mripard@...nel.org, robh+dt@...nel.org,
 tzimmermann@...e.de, devicetree@...r.kernel.org,
 dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org,
 linux-media@...r.kernel.org, chromeos-krk-upstreaming@...gle.com,
 ribalda@...omium.org
Subject: Re: [PATCH v2 8/9] media: dt-bindings: Add Intel Displayport RX IP

On 26/02/2024 11:59, Paweł Anikiel wrote:
>>> +properties:
>>> +  compatible:
>>> +    const: intel,dprx-20.0.1
>>> +
>>> +  reg:
>>> +    maxItems: 1
>>> +
>>> +  interrupts:
>>> +    maxItems: 1
>>> +
>>> +  intel,max-link-rate:
>>> +    $ref: /schemas/types.yaml#/definitions/uint32
>>> +    description: Max link rate configuration parameter
>>
>> Please do not duplicate property name in description. It's useless.
>> Instead explain what is this responsible for.
>>
>> Why max-link-rate would differ for the same dprx-20.0.1? And why
>> standard properties cannot be used?
>>
>> Same for all questions below.
> 
> These four properties are the IP configuration parameters mentioned in
> the device description. When generating the IP core you can set these
> parameters, which could make them differ for the same dprx-20.0.1.
> They are documented in the user guide, for which I also put a link in
> the description. Is that enough? Or should I also document these
> parameters here?

user-guide is something for users, like user-space programmers or
end-users. I would never open it to look for any information related to
hardware.

Anyway, external resources are a no-go. We have it clearly in submitting
patches:

https://elixir.bootlin.com/linux/v6.8-rc6/source/Documentation/process/submitting-patches.rst#L130

> 
>>
>>> +
>>> +  intel,max-lane-count:
>>> +    $ref: /schemas/types.yaml#/definitions/uint32
>>> +    description: Max lane count configuration parameter
>>> +
>>> +  intel,multi-stream-support:
>>> +    type: boolean
>>> +    description: Multi-Stream Transport support configuration parameter
>>> +
>>> +  intel,max-stream-count:
>>> +    $ref: /schemas/types.yaml#/definitions/uint32
>>> +    description: Max stream count configuration parameter
>>> +
>>> +  port:
>>> +    $ref: /schemas/graph.yaml#/properties/port
>>> +    description: SST main link
>>
>> I don't understand why you have both port and ports. Shouldn't this be
>> under ports?
> 
> I put both so that you can use the shorter port property when the
> device only has one port (i.e. no MST support). It would work fine
> without it. If you think that's unnecessary, I can remove it (and use
> the ports property even if there is only one).

No, it is fine, but then you need allOf: which will restrict to only one
of them: either port or ports.

Best regards,
Krzysztof