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Date:   Thu, 16 May 2019 18:48:59 +0200
From:   Torsten Duwe <duwe@lst.de>
To:     Vasily Khoruzhick <anarsoul@gmail.com>
Cc:     David Airlie <airlied@linux.ie>, Daniel Vetter <daniel@ffwll.ch>,
        Rob Herring <robh+dt@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Thierry Reding <thierry.reding@gmail.com>,
        Maxime Ripard <maxime.ripard@bootlin.com>,
        Chen-Yu Tsai <wens@csie.org>,
        Andrzej Hajda <a.hajda@samsung.com>,
        Laurent Pinchart <Laurent.pinchart@ideasonboard.com>,
        Icenowy Zheng <icenowy@aosc.io>,
        Sean Paul <seanpaul@chromium.org>,
        Harald Geyer <harald@ccbib.org>,
        dri-devel <dri-devel@lists.freedesktop.org>,
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Subject: Re: [PATCH 4/4] arm64: DTS: allwinner: a64: enable ANX6345 bridge
 on Teres-I
Message-ID: <20190516164859.GB10431@lst.de>
References: <20190514155911.6C0AC68B05@newverein.lst.de> <20190514160241.9EAC768C7B@newverein.lst.de> <CA+E=qVfuKBzWK7dpM_eabjU8mLdzOw3zCnYk6Tc1oXdavH7CNA@mail.gmail.com> <20190515093141.41016b11@blackhole.lan> <CA+E=qVf6K_0T0x2Hsfp6EDqM-ok6xiAzeZPvp6SRg0yt010pKA@mail.gmail.com> <20190516154820.GA10431@lst.de> <CA+E=qVe5NkAvHXPvVc7iTbZn5sKeoRm0166zPW_s83c2gk7B+g@mail.gmail.com>
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On Thu, May 16, 2019 at 09:06:41AM -0700, Vasily Khoruzhick wrote:
> 
> Driver can talk to the panel over AUX channel only after t1+t3, t1 is
> up to 10ms, t3 is up to 200ms.

This is after power-on. The boot loader needs to deal with this.

> It works with older version of driver
> that keeps panel always on because it takes a while between driver
> probe and pipeline start.

No lid switch, no USB, no WiFi, no MMC. If you disable DCDC1 you'll
run out of wakeup-sources ;-) IOW: I see no practical way any OS
driver can switch this panel voltage off and survive...

> All in all - you don't need panel timings since there's EDID but you
> still need panel delays. Anyway, it's up to you and maintainers.

Let's give it a try.

	Torsten