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Message-ID: <8c28ea3a-68f5-1233-9e79-bd9e09d4f485@linaro.org>
Date:   Tue, 30 May 2023 09:48:48 +0200
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Subject: Re: [PATCH V8 7/7] dt-bindings: bridge: samsung-dsim: Make some flags
 optional
To:     Conor Dooley <conor@kernel.org>, Adam Ford <aford173@gmail.com>
Cc:     dri-devel@lists.freedesktop.org, aford@beaconembedded.com,
        Inki Dae <inki.dae@samsung.com>,
        Jagan Teki <jagan@amarulasolutions.com>,
        Marek Szyprowski <m.szyprowski@samsung.com>,
        Andrzej Hajda <andrzej.hajda@intel.com>,
        Neil Armstrong <neil.armstrong@linaro.org>,
        Robert Foss <rfoss@kernel.org>,
        Laurent Pinchart <Laurent.pinchart@ideasonboard.com>,
        Jonas Karlman <jonas@kwiboo.se>,
        Jernej Skrabec <jernej.skrabec@gmail.com>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        Frieder Schrempf <frieder.schrempf@kontron.de>,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
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From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <20230526-lily-underwent-1dc0be746be0@spud>
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On 26/05/2023 21:30, Conor Dooley wrote:
> On Fri, May 26, 2023 at 02:24:21PM -0500, Adam Ford wrote:
>> On Fri, May 26, 2023 at 1:19 PM Conor Dooley <conor@kernel.org> wrote:
>>> On Thu, May 25, 2023 at 10:05:59PM -0500, Adam Ford wrote:
> 
>>>>      description:
>>>> -      DSIM high speed burst mode frequency.
>>>> +      DSIM high speed burst mode frequency when connected to devices
>>>> +      that support burst mode. If absent, the driver will use the pixel
>>>> +      clock from the attached device or bridge.
>>>
>>> I'd rather this description did not say anything about drivers.
>>> How about:
>>>         If absent, the pixel clock from the attached device or bridge
>>>         will be used instead.
>>
>> That makes sense.  I can do that.
>>
>> "DSIM high speed burst mode frequency (optional). If absent, the pixel
>> clock from the attached device or bridge will be used instead."
>>
>>> Or perhaps "must be used"? Ditto below.
>>
>> "Must be" implies to me that the user needs to set something.  Are you
>> ok with the proposed suggestion above?
>>>
>>> Description aside, the removal seems to be backwards compatible - but
>>> can every device that this binding supports work using an "attached
>>> device or bridge", or are these properties going to be required for
>>> certain compatibles?
>>
>> From what I can tell, the assumption is that the DSIM driver was
>> expecting it to attach to panels in the past.  With the additional
>> patch series, the DSIM can attach to bridge parts without a hard-coded
>> set of clocks.  I don't expect the existing Exynos devices to change,
>> but I also don't know what would preclude those SoC's from attaching
>> to a bridge should someone want to design a new product around them.
> 
> Okay, that seems fair. With your revised wording,
> Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
> 
>>
>> I'll wait a couple days for more feedback and send patch V2 with just
>> this patch since the rest of the series has been applied to the drm
>> branch.
> 
> Sounds good. Krzysztof will hopefully be able to take a look then too to
> make sure I am not making a hames of things.

We should avoid references to driver, because bindings are used also in
other projects where driver can behave differently. Also "driver" is
then ambiguous - which driver do you mean? Please re-phrase.

Best regards,
Krzysztof