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Subject: Re: [PATCH v6 3/3] drm: bridge: cdns-mhdp: add j721e wrapper
To:     Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Yuti Amonkar <yamonkar@cadence.com>
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From:   Tomi Valkeinen <tomi.valkeinen@ti.com>
Message-ID: <0e9b73b7-a960-e2a1-d8a1-f12309755176@ti.com>
Date:   Thu, 12 Mar 2020 09:01:23 +0200
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Hi Laurent,

On 11/03/2020 22:52, Laurent Pinchart wrote:

>> +void cdns_mhdp_j721e_enable(struct cdns_mhdp_device *mhdp)
>> +{
>> +	/*
>> +	 * Eneble VIF_0 and select DPI2 as its input. DSS0 DPI0 is connected
>> +	 * to eDP DPI2. This is the only supported SST configuration on
>> +	 * J721E.
> 
> Without hardware documentation I can't really comment on this, but I'd
> like to make sure it doesn't imply that the MHDP has more than one input
> and one output.

You can download the TRM for j721e here:

http://www.ti.com/lit/pdf/spruil1

MHDP has one DP output, but 4 inputs to support MST and split/dual panel modes. None of those are 
supported by the drivers, but perhaps some thought should be paid to figure out if adding these 
features affect the DT bindings.

  Tomi

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