Messages in this thread | | | Date | Fri, 24 Feb 2012 16:40:39 +0800 | From | Dong Aisheng <> | Subject | Re: [PATCH 08/20] pinctrl: Assume map table entries can't have a NULL name field |
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On Thu, Feb 23, 2012 at 08:39:58AM -0800, Stephen Warren wrote: > Dong Aisheng wrote at Wednesday, February 22, 2012 9:48 PM: > > On Wed, Feb 22, 2012 at 07:53:44PM -0800, Stephen Warren wrote: > ... > > > I'm hoping that we don't do this internal conversion. The rules I'd like are: > ... > > > * Every mapping table entry must include a non-NULL name field. > > > > > > * Every call to pinctrl_get()/pinctrl_lookup_state() must pass a non-NULL name > > > > This is a way. > > > > Before using this, i'm still wondering what big problems do you think for us to support > > a NULL map name? > > Because the name for devices do not have different state really does not make too much > > sense but extra overhead. > > If we disallow NULL names, it simplifies the code in the pinctrl core; > when registering mappings or right at the start of pinctrl_get() or > pinctrl_lookup_state(), we check if the name is NULL and if so error out. > Everywhere else can then assume name!=NULL, and hence not have special- > cases for name==NULL, e.g.: > > In debug code: > name ? name : "(unnamed)" > vs.: > name > > When matching mapping table entries: > match = !name ? !map->name : !strcmp(name, map->name) > vs.: > match = !strcmp(name, map->name) > > Similar for the body of pinctrl_lookup_state(). > Yes, it does make thing simple. But i guess it's not the key point to not support NULL state name, right?
> Equally, it's not possible to generate a mapping table entry with a NULL > name from device tree given the bindings we discussed, so disallowing them > everywhere keeps things consistent. > Yes, i'm wondering if we can change it a bit to support NULL name. I replied with my idea in another mail before this one.
Regards Dong Aisheng
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