Re: iio: dht11 broken

[Richard Weinberger]

Am 01.12.2014 um 15:08 schrieb Linus Walleij:
> On Mon, Dec 1, 2014 at 11:59 AM, Richard Weinberger <richard@xxxxxx> wrote:
>> Am 01.12.2014 um 11:49 schrieb Harald Geyer:
> 
>>> Any input from gpiolib people about what the proper fix would be in
>>> their opinion, of course is appreciated. I don't think the dht11 driver
>>> is doing anything unreasonable per se, so maybe they can clarify how
>>> the API is intended to be used?
>>
>> Your driver sets up a GPIO as IRQ and then you switch the mode to output
>> to enable the DHT sensor.
>> This is not an API issue, it is an design issue.
>> I'm not a hardware expert but AFAIK setting an IRQ pin into output mode can
>> lead to undefined behavior.
> 
> Well that check is there exactly to prevent madness like this.
> 
> IRQs on pins set to output *does* *not* *make* *sense*.
> 
> Remove the IRQ before setting the pin to output and vice
> versa and everyone will be happier.

Thanks for the confirmation.
I'll cook up a patch.

Thanks,
//richard
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