Request for help: HDLCD Controller

Hi!

I am developing a system in which the video support is made through two ARM' HDLCD Controller and two TDA998x HDMI PHYs.

When I try to load ARM' HDLCD driver (hdlcd), it fails when it tries to bind with the drm subsystem:

root@genericarmv8:~# modprobe hdlcd
[drm] found ARM HDLCD version r0p0
hdlcd 7ff50000.hdlcd: master bind failed: -517
[drm] found ARM HDLCD version r0p0
hdlcd 7ff60000.hdlcd: master bind failed: -517

The kernel has the controllers mapped in the I2C bus:

root@genericarmv8:/sys/bus/i2c/drivers/tda998x# ls -l
total 0
lrwxrwxrwx    1 root     root             0 Nov  6 00:44 0-0070 ->
../../../../devices/platform/7ffa0000.i2c/i2c-0/0-0070
lrwxrwxrwx    1 root     root             0 Nov  6 00:44 0-0071 ->
../../../../devices/platform/7ffa0000.i2c/i2c-0/0-0071
--w-------    1 root     root          4096 Nov  6 00:44 bind
--w-------    1 root     root          4096 Nov  6 00:44 uevent
--w-------    1 root     root          4096 Nov  6 00:44 unbind

I know that this driver is not supported in the mainline yet, but did anyone face a similar problem?

Thank you very much for your time!

Regards,
Joao