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Message-ID: <b974c741-9d3e-1229-bcd5-a980035d1fb4@ideasonboard.com>
Date:   Mon, 17 Apr 2023 11:47:39 +0300
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Subject: Re: [PATCH v2 0/2] "no-hpd" support in CDNS DP bridge driver
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To:     Jayesh Choudhary <j-choudhary@ti.com>,
        dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, krzysztof.kozlowski@linaro.org
Cc:     andrzej.hajda@intel.com, neil.armstrong@linaro.org,
        rfoss@kernel.org, Laurent.pinchart@ideasonboard.com,
        jonas@kwiboo.se, jernej.skrabec@gmail.com, airlied@gmail.com,
        daniel@ffwll.ch, robh+dt@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, sam@ravnborg.org,
        jani.nikula@intel.com, tzimmermann@suse.de, javierm@redhat.com,
        ville.syrjala@linux.intel.com, r-ravikumar@ti.com,
        lyude@redhat.com, alexander.deucher@amd.com, sjakhade@cadence.com,
        yamonkar@cadence.com, a-bhatia1@ti.com
References: <20230405142440.191939-1-j-choudhary@ti.com>
From:   Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
In-Reply-To: <20230405142440.191939-1-j-choudhary@ti.com>
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On 05/04/2023 17:24, Jayesh Choudhary wrote:
> In J721s2 EVM, DP0 HPD is not connected to correct HPD pin on SOC
> which results in HPD detect as always connnected, so when display
> is not connected driver continuously retries to read EDID and DPCD
> registers.

Where is the DP0 HPD connected to? Nowhere? If it's connected to a pin, 
can that pin be used as a GPIO? In other words, do we have a HPD, just 
not with mhdp, or is there just no HPD at all?

  Tomi