Raspberry 3 + Asus MB168b

[FMK]

Hi,

I'm currently try to get my asus mb168b to work with my raspberry pi 3.

According to some research on the internet i needed to compile the raspberry kernel with support for displaylink framebuffer.

After some trail and error i finally got this running and I have now a running rpi 3 with kernel 4.4.42-v7+ with framebuffer support enabled.

Wen i plug in the asus display i get this message from dmesg:

[  165.803651] usb 1-1.4.2: USB disconnect, device number 7
[  170.749558] usb 1-1.4.2: new high-speed USB device number 8 using dwc_otg
[  170.850447] usb 1-1.4.2: New USB device found, idVendor=17e9, idProduct=ff03
[  170.850469] usb 1-1.4.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[  170.850483] usb 1-1.4.2: Product: MB168B
[  170.850495] usb 1-1.4.2: Manufacturer: DisplayLink
[  170.850508] usb 1-1.4.2: SerialNumber: G4LMTF010839

lsusb shows me the following output:

Bus 001 Device 008: ID 17e9:ff03 DisplayLink
[...]

Before i enabled the framebuffer support i was not able to install the displaylink drivers because of missing dkms stuff.

With the patched kernel i was able to install the drivers without any problems.

Since it didn't work after the driver installation i looked further and saw that some people said that the "old" udlfb driver was the problem and that one should use the new udl drivers.

So i blacklisted the old udlfb and enabled the new udl drivers.

lsmod:

Module                  Size  Used by
bnep                   10340  2
hci_uart               17943  1
btbcm                   5929  1 hci_uart
bluetooth             326067  22 bnep,btbcm,hci_uart
evdi                   36280  0
brcmfmac              186282  0
brcmutil                5661  1 brcmfmac
cfg80211              428833  1 brcmfmac
joydev                  9024  0
rfkill                 16018  4 cfg80211,bluetooth
snd_bcm2835            20447  1
snd_pcm                75890  1 snd_bcm2835
snd_timer              19288  1 snd_pcm
snd                    51908  5 snd_bcm2835,snd_timer,snd_pcm
bcm2835_gpiomem         3040  0
bcm2835_wdt             3225  0
evdev                  11396  6
uio_pdrv_genirq         3164  0
uio                     8000  1 uio_pdrv_genirq
udl                    21984  0
drm_kms_helper        101028  2 udl,evdi
drm                   262526  3 udl,evdi,drm_kms_helper
i2c_dev                 5859  0
fuse                   84037  3
ipv6                  347537  46

This also did not prove a solution to my problem as there is still no second framebuffer device besides the hdmi one.

What could i do to get the display working?

I've seen some blog posts of people that got the display working but they all had a second /dev/fb* device after booting with the new kernel.

Yours,
FMK

[Mahdi2016]

Hello FMK,

the problem is the ARM hardware architecture from RaspberryPi.

Here is an official statement from the kernel developers of RaspberryPi:
The config option for the DRM module is DRM_UDL,, the equivalent legacy frame-buffer one is FB_UDL, both have no dependencies that aren't already met in the standard kernel build on the Pi. Note that these only work with the older USB 2.0 DisplayLink devices, the USB 3.0 ones use proprietary encryption on the USB link to satisfy HDCP requirements, and thus don't work with Linux (and are not likely to ever work with Linux).

I have the same problem with an USB 3.0 monitor.

According to rumors, an ARM PC with USB 3.0 (e.g. Odroid) should be able to run a USB 3.0 monitor.

Best regards
Michael