[PATCH 01/10] Add a common struct clk

Pavel Machek pavel at ucw.cz
Sat Apr 30 14:30:35 EDT 2011


On Fri 2011-04-29 12:01:15, Russell King - ARM Linux wrote:
> On Fri, Apr 29, 2011 at 12:45:00PM +0200, Thomas Gleixner wrote:
> > On Fri, 29 Apr 2011, Russell King - ARM Linux wrote:
> > 
> > > On Thu, Apr 21, 2011 at 09:48:28PM +0200, Thomas Gleixner wrote:
> > > > On Fri, 15 Apr 2011, Sascha Hauer wrote:
> > > > > From: Jeremy Kerr <jeremy.kerr at canonical.com>
> > > > > + * @get:	Called by the core clock code when a device driver acquires a
> > > > > + *		clock via clk_get(). Optional.
> > > > > + *
> > > > > + * @put:	Called by the core clock code when a devices driver releases a
> > > > > + *		clock via clk_put(). Optional.
> > > > 
> > > > These callbacks are completely pointless. There are only two non empty
> > > > implementations in tree:
> > > > 
> > > > One does a try_module_get(clk->owner), which should be done in generic
> > > > code. The other does special clock enabling magic which wants to go to
> > > > clk->prepare().
> > > 
> > > I disagree.  Most clocks don't live in a module - there's only one
> > > platform which does at present.  To force every clock to have an owner
> > > field is rediculous.  We already know that the OMAP tree represents a
> > 
> > So we trade an owner field (which can be NULL) versus two function
> > pointers in the clk_ops struct, which are of course subject to be
> > abused for all kind of crap which does not belong there at all.
> 
> And the current __clk_get/__clk_put stuff has been abused to hell and
> back hasn't it with just three implementations.  While I agree with your
> sentiment, lets agree to address that _if_ it becomes a problem.  At
> the moment, we have _enough_ problems to deal with, we don't need to
> invent new ones which really don't matter at this stage.

So lets.. add the pointer and see if 4K lost is a problem for
someone...?

It should be 'nice abstractions first, optimalizations later'...
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html



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