[RFC] ARM: OMAP2+: omap_device: add pinctrl handling

Grygorii Strashko grygorii.strashko at ti.com
Thu Jun 27 12:04:41 EDT 2013


On 06/27/2013 05:45 PM, Tony Lindgren wrote:
> * Grygorii Strashko <grygorii.strashko at ti.com> [130627 07:12]:
>>
>> As you can see, from 12 pins only 3 pins need to be reconfigured
>> while switching from "active"->"idle" states and back (and as I
>> mentioned above for OMAP "idle" == "sleep" now).
>>
>> Regarding "OFF" state:
>> OMAP mux HW defines special state for unused pins which is selected
>> by default after reset and need to be selected when device isn't
>> used, for example:
>> _MUXMODE - Functional multiplexing selection for pad
>> 0x0: Select usbb1_hsic_data
>> 0x3: Select gpio_96
>> 0x7: Select safe_mode <<--- pin unused
>
> The off mode bits can be enabled continuously, the mux hardware
> automatically sets them. So sounds like you don't need any
> separate "idle" "sleep" and "off" states, the following should
> do:
>
> "default" (or "static")	static pins that don't need to be touched
> 			after consumer driver probe
>
> "active"		dynamic pins that are not a subset of
> 			"default" needed for runtime; these pins
> 			are the same as "idle" below, but with
> 			different muxing or pinconf device
> 			runtime
>
> "idle"			dynamic pins that are not a subset of
> 			"default" needed for various idle modes;
> 			these pins are the same as "active" above,
> 			but with different muxing or pinconf for
> 			various idle states
>
> Can you please confirm that these named modes are enough for
> your needs?
  Confirm )
>
> If your hardware does not have specific off mode bits, then
> I can understand that you may need one mor state "off".
>
> Regards,
>
> Tony
>

Regards,
-grygorii



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