bb.org-overlays: "File Exists" Error when attempting to load device tree for 'BB-UART1'

[mta....@gmail.com]

Hello All,

I am trying to get CAN working on a Beaglebone Black running the following kernel:

Linux beaglebone 4.4.54-ti-r93 #1 SMP Fri Mar 17 13:08:22 UTC 2017 armv7l GNU/Linux

I am attempting to use the CAN1 interface on the BeageBone as I have done previously on other distriubutions, however when I follow the instructions posted here: https://github.com/RobertCNelson/bb.org-overlays I get an error.

For example, if I try the following:

root@beaglebone:/home/debian#  echo 'BB-UART1' > /sys/devices/platform/bone_capemgr/slots
bash: echo: write error: File exists

Dmesg output:

[   40.829790] bone-pinmux-helper: probe of ocp:P9_31_pinmux failed with error -22
[   40.859306] gpio-of-helper ocp:cape-universal: Allocated GPIO id=0
[   40.859510] gpio-of-helper ocp:cape-universal: Allocated GPIO id=1
[   40.859679] gpio-of-helper ocp:cape-universal: Allocated GPIO id=2
[   40.859851] gpio-of-helper ocp:cape-universal: Allocated GPIO id=3
[   40.860015] gpio-of-helper ocp:cape-universal: Allocated GPIO id=4
[   40.860176] gpio-of-helper ocp:cape-universal: Allocated GPIO id=5
[   40.860351] gpio-of-helper ocp:cape-universal: Allocated GPIO id=6
[   40.860513] gpio-of-helper ocp:cape-universal: Allocated GPIO id=7
[   40.860683] gpio-of-helper ocp:cape-universal: Allocated GPIO id=8
[   40.860852] gpio-of-helper ocp:cape-universal: Allocated GPIO id=9
[   40.861016] gpio-of-helper ocp:cape-universal: Allocated GPIO id=10
[   40.861194] gpio-of-helper ocp:cape-universal: Allocated GPIO id=11
[   40.861365] gpio-of-helper ocp:cape-universal: Allocated GPIO id=12
[   40.861534] gpio-of-helper ocp:cape-universal: Allocated GPIO id=13
[   40.861705] gpio-of-helper ocp:cape-universal: Allocated GPIO id=14
[   40.861874] gpio-of-helper ocp:cape-universal: Allocated GPIO id=15
[   40.875457] gpio-of-helper ocp:cape-universal: Allocated GPIO id=16
[   40.875733] gpio-of-helper ocp:cape-universal: Allocated GPIO id=17
[   40.875912] gpio-of-helper ocp:cape-universal: Allocated GPIO id=18
[   40.876095] gpio-of-helper ocp:cape-universal: Allocated GPIO id=19
[   40.876259] gpio-of-helper ocp:cape-universal: Allocated GPIO id=20
[   40.876418] gpio-of-helper ocp:cape-universal: Allocated GPIO id=21
[   40.876580] gpio-of-helper ocp:cape-universal: Allocated GPIO id=22
[   40.876735] gpio-of-helper ocp:cape-universal: Allocated GPIO id=23
[   40.876889] gpio-of-helper ocp:cape-universal: Allocated GPIO id=24
[   40.881135] gpio-of-helper ocp:cape-universal: Allocated GPIO id=25
[   40.881355] gpio-of-helper ocp:cape-universal: Allocated GPIO id=26
[   40.881558] gpio-of-helper ocp:cape-universal: Allocated GPIO id=27
[   40.881716] gpio-of-helper ocp:cape-universal: Allocated GPIO id=28
[   40.881877] gpio-of-helper ocp:cape-universal: Allocated GPIO id=29
[   40.886404] gpio-of-helper ocp:cape-universal: Allocated GPIO id=30
[   40.886687] gpio-of-helper ocp:cape-universal: Allocated GPIO id=31
[   40.886865] gpio-of-helper ocp:cape-universal: Allocated GPIO id=32
[   40.887041] gpio-of-helper ocp:cape-universal: Allocated GPIO id=33
[   40.887201] gpio-of-helper ocp:cape-universal: Allocated GPIO id=34
[   40.887366] gpio-of-helper ocp:cape-universal: Allocated GPIO id=35
[   40.887526] gpio-of-helper ocp:cape-universal: Allocated GPIO id=36
[   40.887538] gpio-of-helper ocp:cape-universal: ready
[   40.898497] 48022000.serial: ttyS1 at MMIO 0x48022000 (irq = 199, base_baud = 3000000) is a 8250
[   40.908411] 48024000.serial: ttyS2 at MMIO 0x48024000 (irq = 200, base_baud = 3000000) is a 8250
[   40.918518] 481a8000.serial: ttyS4 at MMIO 0x481a8000 (irq = 201, base_baud = 3000000) is a 8250
[   40.930524] eqep 48300180.eqep: ver. 1.0
[   40.940161] eqep 48302180.eqep: ver. 1.0
[   40.957039] eqep 48304180.eqep: ver. 1.0
[   40.975138] omap_i2c 4802a000.i2c: bus 1 rev0.11 at 100 kHz
[   41.016139] bone_capemgr bone_capemgr: slot #4: dtbo 'cape-universaln-00A0.dtbo' loaded; overlay id #0
[   41.020746] asoc-simple-card sound: i2s-hifi <-> 48038000.mcasp mapping ok
[   42.912836] CAN device driver interface
[   43.056608] c_can_platform 481cc000.can: c_can_platform device registered (regs=fa1cc000, irq=210)
[   43.087789] c_can_platform 481d0000.can: c_can_platform device registered (regs=fa1d0000, irq=211)
[  194.362266] bone_capemgr bone_capemgr: part_number 'BB-UART1', version 'N/A'
[  194.362348] bone_capemgr bone_capemgr: slot #5: override
[  194.362391] bone_capemgr bone_capemgr: Using override eeprom data at slot 5
[  194.362439] bone_capemgr bone_capemgr: slot #5: 'Override Board Name,00A0,Override Manuf,BB-UART1'
[  194.375726] bone_capemgr bone_capemgr: slot #5: BB-UART1 conflict P9.24 (#4:cape-universaln)
[  194.384469] bone_capemgr bone_capemgr: slot #5: Failed verification


I have no idea how to move forward and have been stuck here for a few days, does anyone have any suggestions?

[Robert Nelson]

[ 522.712138] bone_capemgr bone_capemgr: slot #6: BB-UART1 conflict
P9.24 (#4:cape-universaln)
[ 522.720969] bone_capemgr bone_capemgr: slot #6: Failed verification

cape-universaln is already loaded so bb-uart1 can't load.. To disable
this, open /boot/uEnv.txt and remove "cape_universal=enable" and
reboot.

Regards,

--
Robert Nelson
https://rcn-ee.com/