Re: drm/msm/mdp5: undefined CONFIG_MSM_BUS_SCALING

From: Rob Clark
Date: Thu Apr 09 2015 - 14:54:35 EST


On Thu, Apr 9, 2015 at 2:12 PM, Paul Bolle <pebolle@xxxxxxxxxx> wrote:
> On Thu, 2015-04-09 at 19:07 +0200, Greg KH wrote:
>> I really don't understand. Why is this code in the kernel tree if it
>> can't be built? How does anyone use this? By taking it and copying it
>> where? If it can't be built, and no one can update it, and of course
>> not run it, why is it here? What good is this code doing sitting here?
>
> The Erlangen bot (courtesy of Valentin, Stefan, and Andreas) has taken
> over what I've been doing for quite some time, but doing it much more
> thoroughly. And my experience tells me that the reports they'll send in
> will trigger more discussions like this one.
>
> A lesson I learned from my daily checks for Kconfig oddities is that
> people go to great lengths defending unbuildable code. (Do a web search
> for ATHEROS_AR231X to find a discussion that dragged on for over three
> years!) Personally I stopped caring after someone insisted on having a
> file in the tree that was in no way connected to the build system: not a
> single line in any of the Makefiles pointed at it. So, as far as I'm
> concerned, if people can't point at a patch pending, somehow, somewhere,
> that would make their code buildable one might as well delete the code.
>
> I really think it's as simple as that.
>

In the example you reference, sure it is as simple as that. But here
we are not talking about files that aren't even referenced by build
system. We are talking about a driver which does build and run on
upstream kernel, and which has a few small #ifdef blocks to simplify
backporting to downstream kernels (which we still do need to use for
some generations and some devices)

Sure, I'd love never to have to deal with a downstream kernel. But
really.. I didn't create the downstream mess in the arm/android
ecosystem, I'm just trying to cope with it as best as possible.. don't
hate the player, hate the game :-P

BR,
-R

>
> Paul Bolle
>
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