linux-kernel - Re: [PATCH v6 11/11] drm/mediatek: dp: Don't register HPD interrupt handler for eDP case

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Message-ID: <f7234a53-2449-426c-4cff-91c89bada258@baylibre.com>
Date:   Thu, 20 Jul 2023 17:55:07 +0200
From:   Alexandre Mergnat <amergnat@...libre.com>
To:     AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@...labora.com>, chunkuang.hu@...nel.org
Cc:     p.zabel@...gutronix.de, airlied@...il.com, daniel@...ll.ch,
        matthias.bgg@...il.com, dri-devel@...ts.freedesktop.org,
        linux-mediatek@...ts.infradead.org, linux-kernel@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org, kernel@...labora.com,
        wenst@...omium.org, nfraprado@...labora.com
Subject: Re: [PATCH v6 11/11] drm/mediatek: dp: Don't register HPD interrupt
 handler for eDP case

Reviewed-by: Alexandre Mergnat <amergnat@...libre.com>

On 17/07/2023 16:14, AngeloGioacchino Del Regno wrote:
> The interrupt handler for HPD is useful only if a display is actually
> supposed to be hotpluggable, as that manages the machinery to perform
> cable (un)plug detection, debouncing and setup for re-training.
> 
> Since eDP panels are not supposed to be hotpluggable we can avoid
> using the HPD interrupts altogether and rely on HPD polling only
> for the suspend/resume case, saving us some spinlocking action and
> the overhead of interrupts firing at every suspend/resume cycle,
> achieving a faster (even if just slightly) display resume.

-- 
Regards,
Alexandre