Re: [PATCH 3/3] UIO: generic platform driver
From: Uwe Kleine-König
Date: Tue May 20 2008 - 05:23:41 EST
Hans J. Koch wrote:
> On Wed, Apr 23, 2008 at 10:56:29AM +0200, Uwe Kleine-König wrote:
> > Hello,
> > Uwe Kleine-König wrote:
> > > Signed-off-by: Uwe Kleine-König <Uwe.Kleine-Koenig@xxxxxxxx>
> > > ---
> > > Hello,
> > >
> > > This is the former patch 4/4 after some discussion.
> > >
> > > Open issues:
> > > - clock name "uio" isn't considered good by Russell King
> > > I don't have a better suggestion
> > I added another branch on my repo that doesn't have the dummy clk
> > patch and variant of this one that doesn't use the clk API.
> > This way the clk API isn't needed anymore for my patch and the issue
> > about the clock name disappeard, too.
> Hi Uwe,
> sorry for the delay, I was away for a few days and had an awful lot of
> work when I came back.
> About your generic platform driver: I think we've got two choices, both
> of them are acceptable as far as I'm concerned:
> 1.) Use the clk API and make your driver depend on it. AFAICS, only ARM
> and PPC implement it right now. On some platforms, it will probably
> never be implemented. E.g. x86 doesn't have any clocks that could be
> controlled that way. It's probably only useful for SoCs.
> Advantages: People who need it get clk support for free, without having
> to write much code.
> Disadvantages: The generic platform driver is not available for all
> platforms. It might not be easy to implement the dependency in Kconfig
> in a way acceptable to all maintainers ;-)
> 2.) Don't use the clk API. I don't think we would lose much. Drivers
> could implement clk stuff in their board support. You could add some
> generic function pointers in struct uio_platdata that are called in
> open/release/probe/remove. That way, any platform specific stuff,
> including clk, could be handled.
> Advantages: The generic platform driver is available for all
> platforms, no need for dependencies in Kconfig.
> Disadvantages: People who need clk_* must write a lot of code within
> their board support file. Not nice and clean...
> I'm ready to accept 1.) or 2.), or even both of them (why can't we have
> two generic platform drivers?)
For now I suggest 2). Using the clk API might be implemented by a
generic open/release routine. Maybe I will look into that at a later
time. For now I'm happy without clk support, too.
For now you can find two patches in my uio branch at
I rebased them to current Linus' master; otherwise they are unmodified
since the last posts. For completeness I'll resend them as a reply to
For shortlog and diffstat see below.
Uwe Kleine-König (2):
UIO: don't let UIO_CIF and UIO_SMX depend twice on UIO
UIO: generic platform driver
drivers/uio/Kconfig | 10 +++-
drivers/uio/Makefile | 1 +
drivers/uio/uio_pdrv.c | 118 ++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 127 insertions(+), 2 deletions(-)
Uwe Kleine-König, Software Engineer
Digi International GmbH Branch Breisach, Küferstrasse 8, 79206 Breisach, Germany
Tax: 315/5781/0242 / VAT: DE153662976 / Reg. Amtsgericht Dortmund HRB 13962
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