[yocto] Accessing BeagleBone Analog inputs

[Chris Kottaridis]

I followed the steps to create a beaglebone found here:

http://www.jumpnowtek.com/beaglebone/BeagleBone-Systems-with-Yocto.html

They worked like a charm, thanksyou junponowtek.

And then followed this doc to try and get the ADC available:

http://processors.wiki.ti.com/index.php/Linux_Core_ADC_Users_Guide

I loaded the module and it shows up in lsmod along with other modules it 
brings in:

# lsmod
Module                  Size  Used by
ti_am335x_adc          16384  0
kfifo_buf              16384  1 ti_am335x_adc
industrialio           57344  2 ti_am335x_adc,kfifo_buf
ti_am335x_tscadc       16384  1 ti_am335x_adc

My arch/arm/boot/dts/am335x-evm.dts file shows

&tscadc {
         status = "okay";
         tsc {
                 ti,wires = <4>;
                 ti,x-plate-resistance = <200>;
                 ti,coordinate-readouts = <5>;
                 ti,wire-config = <0x00 0x11 0x22 0x33>;
                 ti,charge-delay = <0x400>;
         };

         adc {
                 ti,adc-channels = <4 5 6 7>;
         };
};

According to the doc above loading the module should create the following:

 >On loading the module you would see the IIO device created

root at arago-armv7:~# ls -al /sys/bus/iio/devices/iio\:device0/
drwxr-xr-x    5 root     root             0 Nov  1 22:06 .
drwxr-xr-x    4 root     root             0 Nov  1 22:06 ..
drwxr-xr-x    2 root     root             0 Nov  1 22:06 buffer
-r--r--r--    1 root     root          4096 Nov  1 22:06 dev
-rw-r--r--    1 root     root          4096 Nov  1 22:06 in_voltage4_raw
-rw-r--r--    1 root     root          4096 Nov  1 22:06 in_voltage5_raw
-rw-r--r--    1 root     root          4096 Nov  1 22:06 in_voltage6_raw
-rw-r--r--    1 root     root          4096 Nov  1 22:06 in_voltage7_raw
-r--r--r--    1 root     root          4096 Nov  1 22:06 name
lrwxrwxrwx    1 root     root             0 Nov  1 22:06 of_node -> ../../../../../../firmware/devicetree/base/ocp/tscadc at 44e0d000/adc
drwxr-xr-x    2 root     root             0 Nov  1 22:06 power
drwxr-xr-x    2 root     root             0 Nov  1 22:06 scan_elements
lrwxrwxrwx    1 root     root             0 Nov  1 22:06 subsystem -> ../../../../../../bus/iio
-rw-r--r--    1 root     root          4096 Nov  1 22:06 uevent

While the /sys/bus/iio directory got created when I loaded the module 
the device directory is empty

# ls /sys/bus/iio/devices
#

What am I missing that is preventing the ADC interface from being created ?

Any pointers would be appreciated.

Thanks
Chris K