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Date: Tue, 20 Feb 2024 11:49:06 -0800
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Subject: Re: [PATCH v2] drm/dp: move intel_dp_vsc_sdp_pack() to generic helper
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To: =?UTF-8?B?VmlsbGUgU3lyasOkbMOk?= <ville.syrjala@linux.intel.com>
CC: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
        <dri-devel@lists.freedesktop.org>,
        Maarten Lankhorst
	<maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        David Airlie <airlied@gmail.com>, Daniel Vetter <daniel@ffwll.ch>,
        Jani Nikula <jani.nikula@linux.intel.com>,
        Rodrigo Vivi <rodrigo.vivi@intel.com>,
        Joonas Lahtinen
	<joonas.lahtinen@linux.intel.com>,
        Tvrtko Ursulin
	<tvrtko.ursulin@linux.intel.com>,
        <robdclark@gmail.com>, <freedreno@lists.freedesktop.org>,
        <intel-gfx@lists.freedesktop.org>, <quic_jesszhan@quicinc.com>,
        <linux-kernel@vger.kernel.org>, <intel-xe@lists.freedesktop.org>
References: <20240215190834.3222812-1-quic_abhinavk@quicinc.com>
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 <ec5ee910-469e-4224-28ca-336c9f589057@quicinc.com>
 <ZdUAZZIO5Zk2Y8Wm@intel.com>
From: Abhinav Kumar <quic_abhinavk@quicinc.com>
In-Reply-To: <ZdUAZZIO5Zk2Y8Wm@intel.com>
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On 2/20/2024 11:41 AM, Ville Syrjälä wrote:
> On Tue, Feb 20, 2024 at 11:27:18AM -0800, Abhinav Kumar wrote:
>>
>>
>> On 2/20/2024 11:20 AM, Dmitry Baryshkov wrote:
>>> On Tue, 20 Feb 2024 at 21:05, Dmitry Baryshkov
>>> <dmitry.baryshkov@linaro.org> wrote:
>>>>
>>>> On Tue, 20 Feb 2024 at 20:53, Abhinav Kumar <quic_abhinavk@quicinc.com> wrote:
>>>>>
>>>>>
>>>>>
>>>>> On 2/20/2024 10:49 AM, Dmitry Baryshkov wrote:
>>>>>> On Thu, 15 Feb 2024 at 21:08, Abhinav Kumar <quic_abhinavk@quicinc.com> wrote:
>>>>>>>
>>>>>>> intel_dp_vsc_sdp_pack() can be re-used by other DRM drivers as well.
>>>>>>> Lets move this to drm_dp_helper to achieve this.
>>>>>>>
>>>>>>> changes in v2:
>>>>>>>            - rebased on top of drm-tip
>>>>>>>
>>>>>>> Acked-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
>>>>>>
>>>>>> v1 had an explicit comment before the ack:
>>>>>>
>>>>>
>>>>> Yes, I remember the comment. I did not make any changes to v2 other than
>>>>> just rebasing it on drm-tip to get the ack from i915 folks.
>>>>>
>>>>>>>       From my side, with the promise of the size fixup.
>>>>>>
>>>>>> However I observe neither a second patch removing the size argument
>>>>>> nor it being dropped as a part of this patch.
>>>>>>
>>>>>
>>>>> Yes, now that in v2 we got the ack for this patch, I can spin a v3 with
>>>>> the addition of the next patch to remove the size OR as another series
>>>>> so as to not block the main series which needs this patch.
>>>>>
>>>>> I would prefer the latter.
>>>>
>>>> It doesn't work this way. The comment should have been fixed for v2.
>>>
>>> This probably deserves some explanation. Currently there is only one
>>> user of this function. So it is easy to fix it. Once there are several
>>> users, you have to fix all of them at the same time, patching
>>> different drm subtrees. That complicates the life of maintainers.
>>>
>>
>> Yes, understood. Its easier to fix it now if its really needed.
>>
>> Actually, I think the reason the size was passed was to make sure
>> a valid struct dp_sdp *sdp was being passed.
> 
> The size is supposed to be the size of *hardware* buffer where this
> gets written into. But looks like this wasn't done correctly when
> the code was copy-pasted from the HDMI inforframe code.
> 

Alright, in that case, let me post a patch to drop this and let me know 
if that works for you.