Debian 4.4.9, Encoder doesn't work.

Hello. I have installed Debian 4.4.9 on my BeagleBone Green. The debian already has all the neccessary overlays, so i tried to load the device bone_eqep2b by typing

echo bone_eqep2b > /sys/devices/platform/bone_capemgr/slots

everything looks well, and my device is in the slots:

# cat /sys/devices/platform/bone_capemgr/slots
 0: PF----  -1 
 1: PF----  -1 
 2: PF----  -1 
 3: PF----  -1 
 4: P-O-L-   0 Override Board Name,00A0,Override Manuf,bone_eqep2b

but actually device doesn’t work. The dmesg shows the error

#dmesg 

You’re doing something wrong.

$ sudo sh -c “echo ‘eqep2b’ > /sys/devices/platform/bone_capemgr/slots”
[sudo] password for william:
sh: echo: I/O error

$ sudo su

echo bone_eqep2b > /sys/devices/platform/bone_capemgr/slots

cat /sys/devices/platform/bone_capemgr/slots

0: PF---- -1
1: PF---- -1
2: PF---- -1
3: PF---- -1
5: P-O-L- 0 Override Board Name,00A0,Override Manuf,bone_eqep2b

dmesg | grep eqep2b

[45229.947577] bone_capemgr bone_capemgr: part_number ‘eqep2b’, version ‘N/A’
[45229.968472] bone_capemgr bone_capemgr: slot #4: ‘Override Board Name,00A0,Override Manuf,eqep2b’
[45263.895787] bone_capemgr bone_capemgr: part_number ‘bone_eqep2b’, version ‘N/A’
[45263.916737] bone_capemgr bone_capemgr: slot #5: ‘Override Board Name,00A0,Override Manuf,bone_eqep2b’
[45263.937869] bone_capemgr bone_capemgr: slot #5: dtbo ‘bone_eqep2b-00A0.dtbo’ loaded; overlay id #0

Well, actually I suppose it could be the kernel version you’re using:

$ uname -r
4.4.9-bone-rt-r10
$ cat /etc/dogtag
BeagleBoard.org Debian Image 2016-05-01