Hi, Just an update to that, in case anyone fall into the same sort of thing. I actually lacked the fix you sent for the fscanf on the output of bytes_per_datum in the iioutils_get_type function. Maxime On 30/11/2011 15:34, Jonathan Cameron wrote: > Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx> wrote: > >> Hi list, >> >> I'm currently trying to test the buffer output, using the chrdev >> present >> at /dev/iio:deviceN. >> >> So I looked into the generic_buffer.c file which seems to do exactly >> that. >> >> By looking into the source code, my understanding is that samples are >> stored with this frame format : >> >> +--bpe--+--...--+--bpe--+--64 bits--+ >> | Ch 0 | ..... | Ch N | timestamp | >> +-------+-------+-------+-----------+ >> >> the overall "frame" size being stored in >> /sys/..../buffer/bytes_per_datum. >> >> Now, when I execute generic-buffer, it sets up correctly the driver by >> enabling the channels, the buffer, setting the trigger, etc, but >> outputs >> nothing at all. After some number of trigger firing, it finally exits, >> having displayed nothing but >> >> # /root/generic-buffer -n at91_adc -t at91_adc-dev0-external >> iio device number being used is 0 >> iio trigger number being used is 3 >> /sys/bus/iio/devices/iio:device0 at91_adc-dev0-external >> # >> >> which seems pretty odd to me. >> >> But when I do a cat directly on /dev/iio:device0, I get some binary >> data, which indicates that the buffer is filled anyway. >> >> So, is generic_buffer supposed to print something ? If so, what kind of >> output should I expect ? >> Or is it just a poor driver configuration/data storing from me ? > > Probably something about the data format that it doesn't understand. It is pretty dumb so I would guess you are hitting something it doesn't know about yet. >> >> Thanks, >> Maxime >> >> -- >> Maxime Ripard, Free Electrons >> Kernel, drivers, real-time and embedded Linux >> development, consulting, training and support. >> http://free-electrons.com >> -- >> 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 > -- Maxime Ripard, Free Electrons Kernel, drivers, real-time and embedded Linux development, consulting, training and support. http://free-electrons.com -- 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
