OMAPDSS: enable omapdss for ARCH_MULTIPLATFORM

At least core omapdss does not have any build dependencies on ARCH_OMAP2PLUS, and adding this dependency in the Kconfig breaks omapdrm for ARCH_MULTIPLATFORM builds.

Signed-off-by Rob Clark <[email protected]>

Quoted 5 lines · Rob Clark

At least core omapdss does not have any build dependencies on ARCH_OMAP2PLUS, and adding this dependency in the Kconfig breaks omapdrm for ARCH_MULTIPLATFORM builds.

Signed-off-by Rob Clark <[email protected]>

Acked-by Arnd Bergmann <[email protected]>

Quoted 5 lines · Arnd Bergmann

Quoted 4 lines · Rob Clark

At least core omapdss does not have any build dependencies on ARCH_OMAP2PLUS, and adding this dependency in the Kconfig breaks omapdrm for ARCH_MULTIPLATFORM builds.

Quoted 3 lines

Quoted 1 line

Signed-off-by Rob Clark <[email protected]>

Acked-by Arnd Bergmann <[email protected]>

It seems nobody has applied this patch, as it has not shown up in linux-next or upstream. Who should take care of this? If nobody feels responsible, I can put it into arm-soc/fixes.

That would normally be me, but I've been on a long leave, and just came back. It'll take me some time to get back on track.

I don't think it makes sense to add ARCH_MULTIPLATFORM only for omapdss, like this patch does. I think we should add it for omapfb and the panel drivers also.

I did get a report of an omapdss build-break with allyesconfig. It seems to happen because omapdrm and omap_vout use "select" to enable omapdss, instead of depending on omapdss. This causes an illegal config to be created. Perhaps this is the problem that Rob mentions in his patch?

Adding ARCH_MULTIPLATFORM for omapdss, as this patch does, removes (well, hides) the above mentioned problem and allyesconfig works ok. You can still break the config, but you need to manually select the Kconfig options the wrong way.

I have patches to add the ARCH_MULTIPLATFORM for omapdss, and to fix the omap_vout and omapdrm Kconfig files. Each of them changes only one line. Arnd, are you ok with queuing those patches via arm-soc/fixes? Or should I send them individually to respective maintainers?

I can send the patches properly for review, but I've also attached them here so Rob can test.

Quoted 5 lines · On Wednesday 06 February 2013 16:15:57 Tomi Valkeinen wrote:

I have patches to add the ARCH_MULTIPLATFORM for omapdss, and to fix the omap_vout and omapdrm Kconfig files. Each of them changes only one line. Arnd, are you ok with queuing those patches via arm-soc/fixes? Or should I send them individually to respective maintainers?

Quoted 2 lines

I can send the patches properly for review, but I've also attached them here so Rob can test.

The second and third attachment in your mail seem to contain identical patches. I suggested a similar patch myself, but Rob thought his

version was nicer to give better build coverage. We only need either Rob's patch or yours, but not both, as far as I can tell.

Olof can correct me, but I think we currently don't have any other patches queued in arm-soc for 3.8 (after Linus announced he did not want any of the less urgent ones), so I think it would be more fitting if you send one of the patches to Linus, rather than having an arm-soc pull request that only contains one patch in your domain.

Quoted 10 lines · Arnd Bergmann

Quoted 7 lines · On Wednesday 06 February 2013 16:15:57 Tomi Valkeinen wrote:

I have patches to add the ARCH_MULTIPLATFORM for omapdss, and to fix the omap_vout and omapdrm Kconfig files. Each of them changes only one line. Arnd, are you ok with queuing those patches via arm-soc/fixes? Or should I send them individually to respective maintainers?

I can send the patches properly for review, but I've also attached them here so Rob can test.

Quoted 2 lines

The second and third attachment in your mail seem to contain identical patches. I suggested a similar patch myself, but Rob thought his

Hmm? They look different to me... 0002-omap_vout-fix-the-dependency-on-OMAPDSS.patch fixes the dependency for omap_vout, 0003-omapdrm-fix-the-dependency-on-OMAPDSS.patch for omapdrm.

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version was nicer to give better build coverage. We only need either Rob's patch or yours, but not both, as far as I can tell.

I read the related posts, but I'm a bit confused here. Let me summarize what has happened and what are the issues:

I changed omapdss, omapfb and omap panel drivers to be platform independent, and after that they compiled fine on OMAP and x86, and should compile fine on any other platform as well. I thus removed the Kconfig build dependencies for OMAP. This is what I sent for 3.8 merge window.

However, Linus complained that now he's getting asked if he wants to enable omapdss driver when he's building x86 kernel. So Tony made a patch that added the ARCH_OMAP2PLUS dependency to omapdss (and some other omap drivers), which went in.

Now, if I'm not mistaken, Rob then added possibility to build omapdrm on ARCH_MULTIPLATFORM. No problem with that as such, but omapdrm's Kconfig uses select to enable omapdss, which does not work. omapdss was not made to work with others using "select" to enable it, but one should "depend on" to it.

This caused omapdss to be enabled partially when omapdrm is enabled on ARCH_MULTIPLATFORM, causing build failure.

So the real fix to the issue is the 0003 patch, which changes omapdrm to use "depend on", not "select". However, adding only that patch will prevent omapdrm to be built on ARCH_MULTIPLATFORM, as omapdss is not enabled on ARCH_MULTIPLATFORM. That one can be enabled with the 0001 patch.

Adding only 0001 patch will also "fix" the build issue, as then omapdss is properly enabled on allyesconfig ARCH_MULTIPLATFORM build, even if omapdrm erroneously uses select to enable omapdss. However, adding only 0001 will still allow the user to manually break the build by disabling omapdss (I think, I didn't test that).

The difference between my 0001 patch and Rob's patch is that Rob only enables omapdss to be built on ARCH_MULTIPLATFORM, leaving omapfb and omap panel drivers out. Leaving omapfb is not an issue, but if the panel drivers are left out, I don't see how omapdrm can function properly, even if compilation works fine.

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Olof can correct me, but I think we currently don't have any other patches queued in arm-soc for 3.8 (after Linus announced he did not want any of the less urgent ones), so I think it would be more fitting if you send one of the patches to Linus, rather than having an arm-soc pull request that only contains one patch in your domain.

Ok, I'll do that. I'm still not sure if I should send only the 0001 patch, or all three. I guess I'll go for all three if nobody objects.

Rob, can you test the patches so we're sure they do what they are supposed to?

omapdrm still has the 'select' statement in it if you only send the first patch, so it should not be possible to disable omapdss when it is actually needed.

I suggested doing only the minimum that is needed to unbreak the allyesconfig build, which is to enable just omapdss but not omapfb and the displays, in case they don't actually build on anything else.

I would suggest only the first patch, since Linus quite specifically asked only for serious bug fixes. I think an allyesconfig build breakage is serious enough, but doing multiple patches for one bug should not be necessary and is much harder to justify.

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I would suggest only the first patch, since Linus quite specifically asked only for serious bug fixes. I think an allyesconfig build breakage is serious enough, but doing multiple patches for one bug should not be necessary and is much harder to justify.

Well, as I see, the bug is omapdrm using "select", not "depends on". So if I'd have to pick one patch, I'd send 0003. That would fix allyesconfig.

Applying only 0003 means that omapdrm (and omapdss) won't be built on ARCH_MULTIPLATFORM, but building omapdrm on ARCH_MULTIPLATFORM is a feature added in this merge window, so leaving it out is not a regression.

But I'm not sure if I'm being overly pedantic here. Patch 0001 would fix allyesconfig, and allow building omapdrm with ARCH_MULTIPLATFORM. However, the fixing there happens as a side effect, and so the 0001 patch isn't even called a "fix" in its subject. That's the reason I'm a bit reluctant with the 0001 patch as a fix.