ucb1x00 patches

Pavel Machek pavel at ucw.cz
Sun Oct 11 08:14:58 EDT 2009


On Wed 2009-10-07 09:12:35, Russell King - ARM Linux wrote:
> On Wed, Oct 07, 2009 at 09:56:42AM +0200, Marek Vasut wrote:
> > Dne St 7. ????jna 2009 09:13:22 Lothar Wa??mann napsal(a):
> > > Hi,
> > > 
> > > Thomas Kunze writes:
> > > > Hi,
> > > >
> > > > I posted these patches at linux-arm-kernel as part of the patchset
> > > > "collie and SA1100 patches".
> > > > Could you please comment on them? I'd also like to know you opinion on
> > > > moving ucb1x00-ts.c to
> > > > input/drivers/touchscreen.
> > > 
> > > What about the ucb1400_ts.c which is already there?
> > > 
> > 
> > I'd be for unifying all the ucb drivers into a single one, but Russell was 
> > against it iirc.
> 
> They're different beasts, and I really don't think they should be unified.
> They have different register layouts, and different access arrangements,
> which need different handling.
> 
> The result is that the UCB1200/UCB1300 support gets unnecessarily penalised
> when UCB1400 is integrated - instead of merely taking a spinlock and
> accessing the register, you have to ensure everything you do is in thread
> context, including interrupt handlers.

Is it that bad?

If sharing makes sense on source-code level, that kind of penalty
should be acceptable. If it makes more eyes on the sources, it will
still be a win.
									Pavel


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