Debian monitor not found

[Wolfgang T.]

Monitor is working under old kernel 4...
I upgraded debian to 11 and to kernel 5.10.0.10, there I could build evdi
output of

dkms status

evdi, 1.10.0, 5.10.0-10-amd64, x86_64: installed
evdi, 1.9.0+dfsg, 4.19.0-8-amd64, x86_64: installed
evdi, 4.4.24: added
evdi, 5.2.14, 4.19.0-10-amd64, x86_64: built
evdi, 5.2.14, 4.19.0-11-amd64, x86_64: built
evdi, 5.2.14, 4.19.0-12-amd64, x86_64: built
evdi, 5.2.14, 4.19.0-13-amd64, x86_64: built
evdi, 5.2.14, 4.19.0-14-amd64, x86_64: built
evdi, 5.2.14, 4.19.0-16-amd64, x86_64: built
evdi, 5.2.14, 4.19.0-17-amd64, x86_64: built
evdi, 5.2.14, 4.19.0-18-amd64, x86_64: built
evdi, 5.2.14, 4.19.0-8-amd64, x86_64: built
evdi, 5.2.14, 4.19.0-9-amd64, x86_64: built

lsusb

Bus 004 Device 003: ID 17e9:4301 DisplayLink USB3.0 to HDMI Adapter

to be able to build i changed this line in displaylink-installer.sh (added --strip ...)

if ! tar xf "$TARGZ" -C "$EVDI" --strip-components=1; then

But the monitor is not found with xrandr,and also not switched on.
Xorg version 1.20.11

Any help appreciated

[Wolfgang T.]

if you have more providers if you call

xrandr --listproviders

make sure the last provider with modesetting has an associated provider
Switch of unused providers
xrandr --setprovideroutputsource [other active modesetting provider]
Switch last installed provider on
xrandr --setprovideroutputsource [last modesetting provider] 0

And then you also should make a start script which is calling

xrandr --setprovideroutputsource [last modesetting provider] 0