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Subject: Re: [PATCH 1/3] drm: mxsfb: Change driver.name to mxsfb-drm
To:     Fabio Estevam <festevam@gmail.com>, Marek Vasut <marex@denx.de>
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From:   Marek Vasut <marek.vasut@gmail.com>
Message-ID: <22e2aecc-3735-8ad6-3f36-75ae2b8f2498@gmail.com>
Date:   Sat, 16 Jun 2018 01:29:31 +0200
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On 06/16/2018 12:22 AM, Fabio Estevam wrote:
> On Fri, Jun 15, 2018 at 6:36 PM, Marek Vasut <marex@denx.de> wrote:
> 
>> Having two drivers in the kernel with different set of bugs is always bad.
> 
> Sure, but breaking dtb's is also bad.

You picked only the first part of my argument, the less important one ;-)

> Can the mxsfb driver be modified to handle the old style bindings?

Maybe, but do we care ? Cfr my comment about the amount of users who
will be affected by this.

> The IPU drm driver is capable of handling both the old style where the
> display timing is passed in dts and the new drm style.
> 
> For example:
> 
> arch/arm/boot/dts/imx6qdl-sabresd.dtsi uses the drm style binding
> arch/arm/boot/dts/imx6qdl-sabreauto.dtsi uses the old style of passing
> the display timings in dts
> 
> Both formats are accepted by the ipu drm driver.
> 
> Can't mxsfb drm driver support both? Then we don't need to worry about
> breaking dtb's and could safely remove the mxs fbdev driver.

This might be a way forward, but again, does it justify the effort ?
We will be adding compatibility code which we will have to maintain for
maybe a handful of users I think.

-- 
Best regards,
Marek Vasut