SPIDEV ABI change on mainline Linux kernel

FYI - a solution will need to be decided upon for libraries like Adafruit_BBIO

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---------- Forwarded message ----------
From: Robert Nelson
Date: Tue, Jun 26, 2018 at 11:03 AM
Subject: [beagle-alpha] SPIDEV abi change on mainline

Mainline:

debian@beaglebone:~$ ls /sys/devices/platform/ocp/48030000.spi/spi_master/spi*/
device of_node power spi0.0 spi0.1 statistics subsystem uevent
debian@beaglebone:~$ ls /sys/devices/platform/ocp/481a0000.spi/spi_master/spi*/
device of_node power spi1.0 spi1.1 statistics subsystem uevent
debian@beaglebone:~$ ls /dev/spidev*
/dev/spidev0.0 /dev/spidev0.1 /dev/spidev1.0 /dev/spidev1.1

v4.1.x -> v4.9.x

debian@beaglebone:~$ ls /sys/devices/platform/ocp/48030000.spi/spi_master/spi*/
device of_node power spi1.0 spi1.1 statistics subsystem uevent
debian@beaglebone:~$ ls /sys/devices/platform/ocp/481a0000.spi/spi_master/spi*/
device of_node power spi2.0 spi2.1 statistics subsystem uevent
debian@beaglebone:/sys/devices/platform/ocp$ ls /dev/spi*
/dev/spidev1.0 /dev/spidev1.1 /dev/spidev2.0 /dev/spidev2.1

v3.8.13:

debian@beaglebone:~$ ls /sys/devices/ocp.*/48030000.spi/spi_master/spi*/
device power spi1.0 spi1.1 subsystem uevent
debian@beaglebone:~$ ls /sys/devices/ocp.*/481a0000.spi/spi_master/spi*/
device power spi2.0 spi2.1 subsystem uevent
debian@beaglebone:~$ ls /dev/spidev*
/dev/spidev1.0 /dev/spidev1.1 /dev/spidev2.0 /dev/spidev2.1

What to Do:

In v4.14.x i'm patching things so it's v4.1.x > v4.9.x compabile..

But, we should change all the libr's to use the "ocp" directory
lookup's shown above..
```

cc @RobertCNelson