Re: [PATCH] pinctrl: msm: Add support for MSM TLMM pinmux

[Josh Cartwright <joshc@codeaurora.org>]

On Thu, Aug 15, 2013 at 02:58:31PM -0700, Hanumant Singh wrote:
> On 8/15/2013 2:50 PM, Josh Cartwright wrote:
> >On Thu, Aug 15, 2013 at 10:44:03AM -0700, Hanumant Singh wrote:
> >>On 8/14/2013 12:29 PM, Linus Walleij wrote:
> >>>On Tue, Jul 30, 2013 at 1:39 AM, Bjorn Andersson <bjorn@kryo.se> wrote:
> >>>>On Wed, Jul 24, 2013 at 1:41 PM, Hanumant Singh <hanumant@codeaurora.org> wrote:
[..]
> >>
> >>Ok i can switch to using pin groups defined in per soc files.
> >>But in our case we have one soc going into different types of boards.
> >>(atleast 3). In each of the boards the same external devices end up using
> >>different pins. For ex camera on board 1 uses different pin group
> >>then the same camera on board 2. Both having the same SOC.
> >>So in this case the design would be to have all possible pin groups
> >>for different boards enumerated in the same soc-pinctrl.c file?
> >>
> >>Also in this implementation I will have.
> >>1) pinctrl-msm.c => DT parsing and interface to framework.
> >>2) pinctrl-msm-tlmm<version>.c => Register programming and pin types
> >>supported by a particular TLMM pinmux version.
> >
> >It isn't clear to me what you are trying to separate out between 1) and
> >2).  Seems like there should only be pinctrl-msm-tlmm<version>.c.
> >
> The idea is that we should be able to plug in the next TLMM version 4, with
> the pintypes that it supports and its register programming semantics without
> any changes to the DT parsing or interface to the framework. The DT
> information describes the states of the pingroups.
> How we handle them with respect to the pinctrl framework, does not change
> with different versions of the TLMM.

Okay, although I think that might be a bit too much indirection too
soon.

I'd rather the strategy be to have a straightforward driver supporting
TLMMv3 only (with MSM8974 support), and only worry about introducing a
generic TLMM parsing layer when we actually have a need for it.

If nothing else, I'd at least suggest that you rename pinctrl-msm.c to
pinctrl-msm-tlmm.c, if it's going to be housing the TLMM-generic DT
parsing code.

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