linux-kernel - Re: [PATCH v6 06/11] drm/mediatek: dp: Enable event interrupt only when bridge attached

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Message-ID: <7822b114-0ccd-0344-cea0-760b892c85e1@baylibre.com>
Date:   Thu, 20 Jul 2023 15:03:00 +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 06/11] drm/mediatek: dp: Enable event interrupt only
 when bridge attached



On 17/07/2023 16:14, AngeloGioacchino Del Regno wrote:
> It is useless and error-prone to enable the DisplayPort event interrupt
> before finishing to probe and install the driver, as the DP training
> cannot happen before the entire pipeline is correctly set up, as the
> interrupt handler also requires the full hardware to be initialized by
> mtk_dp_bridge_attach().
> 
> Anyway, depending in which state the controller is left from the
> bootloader, this may cause an interrupt storm and consequently hang
> the kernel during boot, so, avoid enabling the interrupt until we
> reach a clean state by adding the IRQ_NOAUTOEN flag before requesting
> it at probe time and manage the enablement of the ISR in the .attach()
> and .detach() handlers for the DP bridge.

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

-- 
Regards,
Alexandre