Re: [PATCH 1/4 v2] mfd: add STw481x driver

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

On Mon, 16 Sep 2013, Wolfram Sang wrote:

> 
> On Mon, Sep 16, 2013 at 02:51:18PM +0100, Mark Brown wrote:
> > On Mon, Sep 16, 2013 at 02:44:35PM +0200, Linus Walleij wrote:
> > 
> > > I've tried to fix this for DT-only I2C devices
> > > and this very driver was the reason.
> > 
> > > But a tiresome regression due to drivers relying on this
> > > i2c_device_id not being NULL and inability to remove it from the I2C
> > > core without refactoring the world ensued, see:
> > > commit c80f52847c50109ca248c22efbf71ff10553dca4
> > 
> > Oh, that was the change...
> > 
> > > Reverted in:
> > > commit 661f6c1cd926c6c973e03c6b5151d161f3a666ed
> > 
> > > For this reason I think:
> > > http://marc.info/?l=linux-next&m=137148411231784&w=2
> > 
> > > I have tentatively given up getting pure DT I2C drivers
> > > to probe, I don't think I have the whole picture, but
> > > Wolfram has serious doubts about this and say we have
> > > to be careful ....
> > 
> > > Wolfram, do you have some ideas on how we should
> > > proceed or ar you happy with merging this as-is?
> > 
> > I'd have expected that it should be possible to change things such that
> > the change in the core doesn't produce any change in behaviour for
> > existing drivers.  Can we not change the patch so that i2c_match_id()
> > copes with getting a NULL id_table?  Something like this:
> 
> I hacked something like this after Linus posted his approach. However, I
> found out that run time instanciating ('new_device' file) needs an
> id_table. I wasn't to keen on disabling the feature for dt-only drivers.
> That's where I stopped, due to lack of time.

So in the mean time are you happy with this "dummy" approach?

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
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