Re: [PATCH v4 6/6] pinctrl: add pinctrl gpio binding support

[Stephen Warren <swarren@wwwdotorg.org>]

On 05/29/2012 09:01 PM, Dong Aisheng wrote:
> On Sun, May 27, 2012 at 09:39:19AM -0600, Stephen Warren wrote:
>> On 05/26/2012 10:52 AM, Dong Aisheng wrote:
>>> On Fri, May 25, 2012 at 10:03 AM, Stephen Warren <swarren@wwwdotorg.org> wrote:
>>>> On 05/25/2012 07:36 AM, Dong Aisheng wrote:
>> ...
>>>> If we don't do that, [lock ranges[i].gc] I would argue that we
>>>> shouldn't store ranges[i].gc, since it might become invalid - I
>>>> believe the only use of it is withinthis function?
>>>>
>>> In my option, i think it's ok to store it since they're just some data
>>> to describe
>>> hw properties. The gpio function may become invalid but not data.
>>> Is it reasonable to you?
>>
>> The problem is that if someone tries to dereference the gc field, and
>> it's no longer valid, which could cause an OOPS. Perhaps we can get away
>> just with a comment in the struct definition indicating that this field
>> should only be used by drivers that provided the gc field directly
>> rather than having it set up by DT, but then why even store it when
>> creating the ranges from DT in that case?
>
> Yes, you're right.
> Maybe we could both not store the gc filed for DT (currently we did not see
> the need to store it for dt, right?) and add a comment in the struct definition
> as you said. For non-dt users the driver owner should manage that field
> correctly with lock since it's provided directly by driver.
> Is that ok?

Yes, that makes sense to me. Thanks.