Re: [PATCH V5 2/2] mfd: stmpe: Update DT support in stmpe driver

[Lee Jones <lee.jones@linaro.org>]

On Thu, 06 Dec 2012, Viresh Kumar wrote:

> On 6 December 2012 15:41, Lee Jones <lee.jones@linaro.org> wrote:
> > So then I'm back to my original question, why?
> >
> > What is it used for? What difference does it make?
> >
> > I could understand if the .data attribute was used in the driver
> > to make vital decisions based on STMPE version, but it's not. So
> > why are we burdening the driver with unused code that's not
> > required? Other than to get your mainlined patch-count up of
> > course? This has an air of "placing header files in alphabetical
> > order" about it. ;)
> 
> The count would still be the same as some part of this patch will
> go :)
> 
> I said that because of Grant's comment: "An of_match_table is the
> robust way of identifying specific devices and allows for matching
> against any entry in the compatible list."
> 
> So, thought its better we keep it.

Only if you're going to use it, or else it's just unused cruft.

> Now, the problem is, with this new table we will bind device and
> driver based on of_device_id table and probe it using device_id
> table. Ahh.. that's broken. Maybe yes, can remove it unless we
> have a real need of it.

Broken or otherwise, if it's unused, it's cruft. :)

> >> By chance
> >> our non-DT and DT tables had a difference of "st," only in the name
> >> of instances and so it worked without tables. Otherwise it couldn't
> >> have worked.
> >>
> >> Over that, i am looking to bring the "stmpe,id" binding back again (unless
> >> you have a better option), as device name is not coming from DT currently,
> >> which we discussed earlier.
> >
> > Or you could not put unnecessary bindings into the Device Tree
> > by putting two and two together and realise that using the table
> > is the correct thing to do instead. This actually gives reason
> > to you previous patch, but should probably be fixed-up into it
> > so it has some proper meaning/purpose. ;)
> 
> Couldn't understand this one :(

Really?

Let's break it down - what do you need "stmpe,id" for?

-- 
Lee Jones
Linaro ST-Ericsson Landing Team Lead
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