On Mon, Dec 1, 2014 at 10:06 PM, Lars-Peter Clausen <lars@xxxxxxxxxx> wrote: > On 11/26/2014 01:58 PM, Daniel Baluta wrote: >> >> On Tue, Nov 25, 2014 at 7:29 PM, Jonathan Cameron <jic23@xxxxxxxxxx> >> wrote: >>> >>> >>> >>> On November 25, 2014 5:00:11 PM GMT+00:00, Lars-Peter Clausen >>> <lars@xxxxxxxxxx> wrote: >>>> >>>> On 11/25/2014 05:55 PM, Daniel Baluta wrote: >>>>> >>>>> On Tue, Nov 25, 2014 at 6:36 PM, Lars-Peter Clausen <lars@xxxxxxxxxx> >>>> >>>> wrote: >>>>>> >>>>>> On 11/25/2014 01:48 PM, Vlad Dogaru wrote: >>>>>>> >>>>>>> >>>>>>> This is an attempt to address the problem of buffering in devices >>>> >>>> which >>>>>>> >>>>>>> have >>>>>>> different scan frequencies for different channels. >>>>>> >>>>>> >>>>>> >>>>>> Will these frequencies still be related or completely arbitrary? >>>>> >>>>> >>>>> For Kionix KMX61 we have the same set of frequencies for >>>>> accelerometer and magnetometer (12.5, 25, 50, 100 Hz, etc) >>>>> but for example at some point accel can be configured with 100 Hz >>>>> and magnetometer with 12.5Hz. >>>>> >>>>> Does this matter? >>>> >>>> >>>> I'm wondering if it makes more sense to register multiple buffers or >>>> devices >>>> if the frequencies are completely unrelated. E.g. in the KMX61 case it >>>> looks >>>> as if its simply two logical devices in the same physical package. >> >> >> I think this makes a lot of sense for kmx61 and offers a cleaner >> interface to user space. >> >>>> >>>> - Lars >>> >>> That is how we have handled this so far. >>> Sometimes we have separate iio_devices for >>> the logical functions e.g. hid-sensors and sometimes just multiple >>> buffers.. I am >>> struggling to find it now but one of the ADC drivers had a insanely >>> complex nest >>> sampling arrangement requiring 8 buffers. Final driver might have been >>> simplified though... We might still need a few tweaks >>> for multiple buffers not to having naming clashes.... Moving house so >>> only have phone to hand! >> >> >> I looked into iio/adc/ and iio/imu/ but couldn't find any driver which >> has one IIO device and multiple buffers. I don't see how this can >> work :). >> >> User space application will read /dev/iio:deviceX to get data >> samples. How would they know the source of the data samples? > > > What exactly do you mean by source? By source I mean accelerometer or magnetometer in the case of KMX61 sensor. > >> >> Let me know where is the source code for the 8 buffers ADC driver, >> I am very curious about the implementation :). > > > I think that one never made it into upstream or got reworked before. Ok :) -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
