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Date:   Thu, 28 Apr 2022 10:26:43 +0200
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Subject: Re: [PATCH v4 5/5] usb: host: add xhci-exynos driver
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To:     Jung Daehwan <dh10.jung@samsung.com>
Cc:     Mathias Nyman <mathias.nyman@intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "open list:USB XHCI DRIVER" <linux-usb@vger.kernel.org>,
        open list <linux-kernel@vger.kernel.org>,
        Howard Yen <howardyen@google.com>,
        Jack Pham <jackp@codeaurora.org>,
        Puma Hsu <pumahsu@google.com>,
        "J . Avila" <elavila@google.com>, sc.suh@samsung.com,
        Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
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 <20220428063634.GF151827@ubuntu>
 <fa113ba0-1221-de93-a18f-e4e942cdb261@kernel.org>
 <20220428075305.GH151827@ubuntu>
From:   Krzysztof Kozlowski <krzk@kernel.org>
In-Reply-To: <20220428075305.GH151827@ubuntu>
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On 28/04/2022 09:53, Jung Daehwan wrote:
> On Thu, Apr 28, 2022 at 09:31:56AM +0200, Krzysztof Kozlowski wrote:
>> On 28/04/2022 08:36, Jung Daehwan wrote:
>>>>
>>>> Since you called everything here as "exynos" it is specific to one
>>>> hardware and not-reusable on anything else. How can then you use some
>>>> other compatible? It would be a misuse of Devicetree bindings.
>>>>
>>>
>>> I got it. Let me add them. Is it still necessary if it is only used by
>>> other module on runtime as I said above?
>>
>> Except what Greg wrote, if by "other module" you mean out-of-tree, then
>> the patchset will not be accepted as it is unusable for Linux users.
>> Basically it would be a dead code in Linux kernel.
>>
>> Best regards,
>> Krzysztof
>>
> 
> I wanted to submit patches of just xhci. Let me add a patch together of other
> module(dwc3-exynos) that is in-tree on next submission.
> 
> Is it still necessary to add compatible or bindings in this case?

The answer depends on:
1. Is it possible to use the code without compatible and bindings?
2. Does the new feature changes the hardware description or hardware
behavior? IOW, does it change the meaning of existing bindings?
3. How does it fit to the process explained in
bindings/submitting-patches.rst?


Best regards,
Krzysztof