Re: [PATCH v1 2/2] iio:iio-interrupt-trigger: sysfs poll support

[Gregor Boirie <gregor.boirie@parrot.com>]

On 02/22/2016 12:37 PM, Lars-Peter Clausen wrote:
> Add a sysfs file entry for each interrupt trigger instance allowing
> userspace to :
> * poll for interrupt events ;
>>> Why?
>> On our platform, several sensors are driven by a dedicated "real-time"
>> CPU (bare-metal context). This CPU interrupts Linux in a periodic manner
>> which in turn wakes a user process up to perform sensor fusion.
>> This sysfs poll support allows the user process to explictly wait for
>> this dedicated CPU interrupt to fetch data located in RAM then process
>> them.
> So you are only using the IIO trigger in this setup, but no buffers or
> devices? If you just want to forward the interrupt to userspace UIO might be
> the better solution in this case:
> https://www.kernel.org/doc/htmldocs/uio-howto/about.html
>
> - Lars
I forgot to mention I also need the trigger to initiate in-kernel sampling
for other IIO devices. These samples are also retrieved by the process 
performing
fusion.
>
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