[Gta04-owner] We need an Android kernel

[Paul Kocialkowski]

Le mercredi 17 juillet 2013 à 15:49 +0200, Dr. H. Nikolaus Schaller a
écrit :
> > It is far from perfect.
> 
> I didn't expect that it would be perfect...

I quickly looked at the diff from the android-3.4 kernel and mainline,
and there are many changes there are there that 3.7 doesn't include. If
we decide to stick with 3.7, we'll have to look at each of them
carefully. Anyway the point is that there is a lot of work, and perhaps
adding gta04-specific drivers and stuff on an android kernel would be
easier (that is, if suspend/resume works).

> If nobody decides to go this way, uses and tests the kernel and others
> are working to fixing things, it will never become stable.

I think we are still in the phase where we evaluate carefully our
options and look at what is the easiest choice. I am still not convinced
using 3.7 and adding Android stuff on top is the way to go. I'll also
look at GNUtoo's work on 3.8 (which has complete Android support on
AOSP's common kernel repo).

> > So the situation is the same as it was when we tested Neil's 3.7 kernel.
> > However, it is true that suspend/resume works better than on the 3.0
> > kernel.
> 
> That is IMHO an important point since I think nobody will be willing to
> invest much into 3.0 or 3.4 suspend/resume issues if it works on 3.7 and
> later.

That's right. Moreover, I'm not skilled to debug suspend/resume and it
seems like such a huge task that I don't even want to try.

> > I think I'll give 3.4 a try, depending on how suspend/resume works
> > there, it might be worth investigating that way instead.
> 
> Yes, for a comparison this will be very important to know. 

So I just spent the last 2 days trying to figure out why /dev remained
empty on the android 3.4 kernel. Turns out it was the battery driver's
fault (for some reason, it didn't work and made sysfs hang), I disabled
it for now and will keep going by evaluating how well the rest works.

> Nevertheless I think it is more valuable investing time to fix the issues
> that appear in the 3.7 kernel than working on (different) bugs of 3.4...

Again, that depends on the bugs and the complexity of the tasks. Merging
all the Android changes seems more challenging than fixing separate
gta04-specific drivers. I think we still need to clearly figure out what
is the todo list for each kernel and decide then.

> Maybe you (and we as testers) can file the issues here:
> 
> http://projects.goldelico.com/p/gta04-kernel/issues/
> 
> > 
> >> As soon as you are happy with it, please push to the repo so that I (we)
> >> can sync and try ourselves...
> 
> Is it possible to "push" several different kernel trees to the Replicant repo?
> I.e. that we can choose to repo-sync / compile the 3.0, 3.4 and 3.7 kernels?

It works like an usual git repo: you can push wherever you want, add
other remotes, checkout their contents, etc. When a new commit is
available from Replicant, it will be fetched by repo and may be checked
out (replacing your current HEAD) if it's in the branch that is
designated as the default one for replicant-4.0.

I will try to push as soon as things get interesting. Basically I fear
that pushing too early will be a waste of time (for pusing) as well as
disk space (everyone fetches the new branch with the next repo sync), so
I'd rather do it only when it's worth it. On the other hand, I can also
push somewhere else (like on my personal git.paulk.fr space): that
shouldn't be a problem.