Re: [PATCH v2 6/6] ARM: sun8i: dts: Add Ippo-q8h v1.2 with A33 and 1024x600 lcd support

From: Maxime Ripard <maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
To: Hans de Goede <hdegoede-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Cc: Pantelis Antoniou
	<pantelis.antoniou-OWPKS81ov/FWk0Htik3J/w@public.gmane.org>,
	Chen-Yu Tsai <wens-jdAy2FN1RRM@public.gmane.org>,
	Vishnu Patekar
	<vishnupatekar0510-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>,
	linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org,
	devicetree <devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
	linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
Subject: Re: [PATCH v2 6/6] ARM: sun8i: dts: Add Ippo-q8h v1.2 with A33 and 1024x600 lcd support
Date: Tue, 16 Jun 2015 19:41:14 +0200	[thread overview]
Message-ID: <20150616174114.GI11732@lukather> (raw)
In-Reply-To: <557C3BD3.6030105-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>

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Hi,

On Sat, Jun 13, 2015 at 04:18:59PM +0200, Hans de Goede wrote:
> >Pantelis, to sum things up, we have a case of a tablet that comes with
> >the exact same board, but coming in two flavours with two differents
> >screen resolutions. It looks like a great case for your DT quirks
> >work, but we have no way of runtime detecting the difference between
> >the two variants. What do you think about this? Should we go with
> >using the DT quirks or is this simply out of scope?
> >
> >There's not so much example of similar cases in the kernel, and none
> >of them use quirks so far (obviously) but they all boil down to either
> >the solution you were suggesting in that patch or adding the alternate
> >configuration as a comment.
> >
> >I don't think the latter would work for you, and I agree with that, so
> >I guess that depending on what Pantelis says, either we go with a
> >better solution using the quirks, or we end up using what you
> >suggested (with a nitpick though, I'd prefer if you used the display
> >standard instead of the resolution, which would make it xga I guess?)
> 
> If we go with a separate dts file for each of the 800x480 and 1024x600
> screens, I would greatly prefer to stick with the lcd1024x600 in the dts
> filename instead of using something like xga, the fact that you say:
> "I guess" that my answer to that is: I dunno I would need to look this
> up in wikipedia or some such makes me think that using a qualifier like
> xga is not going the help end users decide which dts file to pick, it
> will just lead to them needing to go to wikipedia too. Also note that
> the advertising of these tablets on ebay / aliexpress almost always
> uses the resolution and not something like "xga".
> 
> So all in all if we do not decide to use quirks for this I would like
> to keep the filename as is.

Yeah, except that the display standard is also encoding the refresh
rate and color depth, that might change from one board to another.

Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com