Query on pinctrl usage for DT nodes

Stephen Warren swarren at wwwdotorg.org
Mon Apr 15 12:40:20 EDT 2013


On 04/15/2013 02:19 AM, Peter Ujfalusi wrote:
> Hi,
> 
> On 04/03/2013 08:42 PM, Tony Lindgren wrote:
>> Oh it's already using pinctrl-single,bits option. Maybe there's a
>> bug, adding Peter to cc.
> 
> I think all boils down to the fact that in pinctrl (single only?) _one_
> register can be only associated with _one_ driver. Even through ,bit type
> would allow us to only change parts of the same register, another device can
> not take the same register with different mask.

pinctrl itself certainly imposes no such restriction that I'm aware of.
pinctrl is only concerned with the ownership of *pins* (or perhaps
groups). The mapping of pins to registers is something entirely internal
to individual pinctrl drivers.

So, the solution here is for pinctrl-single to create a separate
pin/group object for each separately controllable entity, and that may
be each bit in a register rather than each register, depending on HW.



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