Hoping you guys can help me out on this:

Goal: High sample rate of one ADC line via a kernel module and a 
corresponding user space app

Now I know the PRU would be great for this- and I plan on also writing a 
pru version to bench mark the diff but I'm currently trying to get it done 
with a kernel module and its turned into one of those annoying obsessions 
that should work and damn it-- I am going to make it work 

So the goal is almost identical to the generic_buffer.c application 
referenced on this wiki [ 
http://processors.wiki.ti.com/index.php/AM335x_ADC_Driver's_Guide] 

but I've been fight it for awhile with no results. 

Current version: Linux beaglebone 3.8.13-bone70 
1: pulled there git repo 
2: applied the patch to get rid of the trigger stuff found here 
3: compiled:
    gcc --static generic_buffer.c -o generic_buffer
4: Issues happen now because sysfs seem to be so different, I'm not sure 
contionous mode can be turned on? 

    ./generic_buffer -n tiadc -l 256 -c 1
    iio device number being used is 0
    Problem reading scan element information
    diag /sys/bus/iio/devices/iio:device0
     

5: This error leads down the rabbit hole to this semi unhelpful blog post: 
https://e2e.ti.com/support/arm/sitara_arm/f/791/t/365886 yielding an errata 
about `Continuous capture mode is not supported in the 3.12 kernel`; great 
we are still rocking a 3.8.13 kernel thus should be fine? 

--------------------------
Couple questions: 
1: Is there bbb kernel version that plays nice with the iio driver that 
will allow this generic_buffer.c to work? if so details please
2: if not has anyone modified this demo app to make things work? I've seen 
a couple posts about it here  
2: Is there any information to say screw it and read the adc values 
directly in my own ko? I've seen instructions on gpio but not the adc 
lines. 

-- 
For more options, visit http://beagleboard.org/discuss
--- 
You received this message because you are subscribed to the Google Groups 
"BeagleBoard" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
For more options, visit https://groups.google.com/d/optout.

Reply via email to