Messages in this thread | | | From | Linus Walleij <> | Date | Tue, 13 Sep 2016 14:29:24 +0200 | Subject | Re: lockdep: incorrect deadlock warning with two GPIO expanders |
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On Mon, Sep 12, 2016 at 5:33 PM, Peter Zijlstra <peterz@infradead.org> wrote: > On Mon, Sep 12, 2016 at 05:16:14PM +0200, Bartosz Golaszewski wrote:
>> AFAIK there is no clean way to tell that a GPIO is used by an I2C >> multiplexer at probe time. Linus, Alexandre could you confirm?
Nominally, the GPIO descriptors are just abstract resources such as regulators or clocks, they can be used for a lot but just like a clock, regulator, dma channel etc does not know who is using it and for what, it does not know this, no.
> You cannot inspect the device tree while probing?
Of course it *can* but we would end up encoding a special case every time something like this happens, tied to just device tree, then another bolt-on for ACPI etc.
I have a hard time following the problem really, I'm afraid I'm simply just not smart enough :(
Yours, Linus Walleij
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