Messages in this thread | | | Date | Tue, 25 Jun 2013 17:47:14 +0200 | Subject | Re: [PATCH 2/2] Make non-linear GPIO ranges accesible from gpiolib | From | Linus Walleij <> |
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On Tue, Jun 25, 2013 at 5:31 PM, Stephen Warren <swarren@wwwdotorg.org> wrote: > On 06/25/2013 08:56 AM, Linus Walleij wrote: >> On Fri, Jun 21, 2013 at 11:17 PM, Stephen Warren <swarren@wwwdotorg.org> wrote: >>> On 06/20/2013 05:57 AM, Christian Ruppert wrote: >> >>>> Your remark seems to reflect one of the following two hardware >>>> architectures: >>>> >>>> +- SPI >>>> Physical pins --- GPIO --- pinctrl -+- I2C >>>> +- mmc >>> >>> (that's diagram 1) >>> >>>> >>>> +- GPIO >>>> Physical pins -+ +- SPI >>>> +- pinctrl -+- I2C >>>> +- mmc >>> >>> (that's diagram 2) >>> >>>> TB10x hardware architecture: >>>> >>>> +- SPI >>>> Physical pins --- pinctrl -+- I2C >>>> +- mmc >>>> +- GPIO >>> >>> (that's diagram 3) >>> >>> No, I was thinking of diagram 3 above. I'm not sure if diagrams (1) or >>> (2) are common or exist? >> >> The U300 pin controller is obviously of type (1) as it can spy on >> the signals. > > U300 HW might be diagram (1) - I can't say since I'm not familiar with > the HW. However, the fact that GPIO can spy on signals in no way at all > implies that the HW must conform to diagram (1).
That's true. And I don't know what it actually is in this case. That hardware is actually weird in many ways, thanks to helpful HW engineers modeling use cases into the HW.
>> The Nomadik pin controller is basically type (2).
This I know however to be true, as I have access to the low-level schematics of the ASIC.
Yours, Linus Walleij
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