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        DisplayLink Ubuntu Software Release Note

Version: v5.8.0
Build: posix/63-3581-g15996285140 (33)

Date: 21st July 2023

Extensible Virtual Display Interface version included: v1.14.1 (83bb793)
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A. Introduction
===============

This is DisplayLink Driver Software v5.8.0 for Ubuntu. It provides production quality support for DisplayLink USB 3.0 devices on specific variants of desktop Ubuntu Linux.

The driver enables video support for products using DisplayLink USB 3.0 technology. Standard native Ubuntu drivers provide support for DisplayLink audio and ethernet interfaces.


A1. Important notes about DisplayLink firmware
=======================================================================

This software release contains an embedded firmware image. DL-7xxx, DL-6xxx, DL-5xxx, DL-3xxx and DL-41xx devices will be automatically upgraded with this firmware upon connection if required.

The upgrade is silent, therefore screens connected to DisplayLink devices may require a few seconds to appear when devices are connected for the first time, or after devices have been used on other platforms and OSes.

B. Contents
===========

A.  Introduction
A1. Important notes about DisplayLink firmware
B.  Contents
C.  Changes in this release
D.  Supported O/S variants
E.  Release components
F.  How to install
G.  Supported features & hardware
H.  Limitations & known issues
I.  Future development

C.  Bugs fixed in this release
==============================

C.8  Changes in 5.8 release
-----------------------------
- Alpha support for DisplayLink DL-7400 products
- Support for new DisplayLink DL-6150 products
- Support for Ubuntu 23.04
- Added preliminary support for kernel 6.5

C.7  Changes in 5.7 release
-----------------------------
- New driver distribution channel via Synaptics apt repository (https://www.synaptics.com/sites/default/files/Ubuntu/)
- In some cases DisplayLink installer freezes when Secure Boot is enabled. (PS-2455)
- In some cases DisplayLink evdi driver is not signed and loaded when Secure Boot is enabled. (PS-2455)
- Added preliminary support for kernel 6.2
- Added preliminary support for Ubuntu 23.04

C.6  Changes in 5.6.1 release
-----------------------------
- Added support for new DisplayLink DL-6350 products
- DL-6xxx series: fixed LAN sent package status for half-duplex 100M fixed switch config (VIFR-1040)
- DL-6xxx series: fixed timing issue on some modes with Dell AW2721D monitor (VIFR-1045)

C.5  Changes in 5.6 release
-----------------------------
- Added preliminary support for kernel 5.18
- Added support for Ubuntu 22.04
- DL-6xxx series: Improve 10M/100M Ethernet performance of some devices (VIFR-994)
- Fixed laggy video experience on machines with AMD GPUs on XServer (PS-1828)
- Improved stability of connection for some of DL-6xxx devices (PS-1820)
- Improved installer experience (PS-1825)
- DL-5xxx series: System shows unsupported 4kp60 mode on display modes list (PS-1780)
- Fixed installation on Raspberry Pi 64bit (PS-1154)
- Some laptops with DisplayLink driver stuck with black screen before log-in screen appears (PS-1808)
- Fix kernel bugcheck in dma-buf on device plug-in (PS-1691)
- Fixed drm device leaks on evdi module unload (PS-1839)

C.4  Changes in 5.5 release
-----------------------------
- Added preliminary support for kernel 5.17
- Community fixes for evdi kernel module
- DL-6xxx series: update for RTL8211FD-VX and RTL8211E Ethernet PHYs (WS-1597)
- DL-6xxx series: update for LAN LED behavior in some devices (VIFR-840, VIFR-802)
- Fix displays blinking on device connect (PS-1674)
- Mitigate problems with some DP monitors that are black on some DL-6xx0 devices (PS-1560)
- Fix corruptions under cursor in X session on DL-3xx0 devices
- Fix runit scripts for displayLink-driver daemon

C.3  Changes in 5.5 beta release
-----------------------------
- Added support for kernel 5.14 and 5.15
- Added preliminary support for kernel 5.16
- Community fixes for evdi kernel module
- DL-6xxx series: adding RTL8211FD-VX and RTL8211E Ethernet PHYs (WS1597)
- DL-41xx: improved firmware flashing time, visible from following update onwards

C.2  Changes in 5.4.1 release
-----------------------------
- Added support for kernel 5.13
- Added beta support for kernel 5.14 beta (33194)
- DL-6xxx series: improved 5120x1440 - 5K Super Ultrawide resolution selection (33186)
- Improved performance: added support for damage regions interface from Linux DRM interface (26378)
- Improved performance in Wayland session with AMD GPU machines (33151)
- DL-6xxx series: fixed blinking mouse cursor while moving across displays (32987)

C.1  Changes in 5.4.0 release
-----------------------------
- Added support for kernel 5.11 and 5.12
- DL-6xxx series: added support for nVidia G-SYNC monitors
- DL-6xxx series: added 5K Ultrawide (5120x1440 @ 60 Hz) display support
- Other reliability improvements


D. Supported O/S variants
=========================

This release has been prepared to be compatible with Ubuntu 23.04, 22.04, 21.10, 20.04, 19.04 and 18.04.
Other variants and editions may be compatible if they meet minimum O/S requirements, but are not supported by DisplayLink.

The Software contains binaries which work on i686, amd64, armv7 and aarch64 architectures.
Supported Linux Kernel version range is from 4.15 to 6.5.
Minimum supported Xorg version is 1.16, minimum supported Mutter (Wayland) version is 3.32.

E. Release components
=====================
The Software consists of an open-source kernel mode driver (EVDI) with an accompanying library (libevdi),
and a supporting binary application compatible with i686, amd64, armv7 and aarch64 platforms.
Source code for the open-source components can be found at Synaptics' DisplayLink GitHub, https://github.com/DisplayLink

F. How to install
=================

To install the release, from a terminal window, with root permissions use the command:

sudo ./displaylink-driver-XXXX.run

Where displaylink-driver-XXXX.run is the name of the extracted DisplayLink driver.

The dkms framework is required for installation of DisplayLink. This can be installed with the command: sudo apt-get install dkms

More detailed information on installation can be found at http://support.displaylink.com/knowledgebase/articles/615714#ubuntu

G. Supported features & hardware
================================

This driver will support up to 2 displays connected to DisplayLink devices. More than 2 DisplayLink displays may work, but not supported or tested by DisplayLink.

Resolutions up to 4K are supported on the appropriate DisplayLink hardware.

Device families supported:
- DL-7xxx
- DL-6xxx
- DL-5xxx
- DL-41xx
- DL-3xxx

DL-1x5 and DL-1x0 devices use the open source udl driver, which is not developed or maintained by Synaptics.

H. Limitations & known issues
=============================

A list of limitations and known issues can be found here:
http://support.displaylink.com/knowledgebase/articles/641668

- Gnome with Wayland or X11 desktop support up to four 4k display in a row. (PS-2955)
Anything wider might cause mouse issues or video glitches.

- Fail to rotate display on three-monitor desktop on Ubuntu 22.10 (PS-2230)
https://gitlab.gnome.org/GNOME/gnome-control-center/-/issues/2113
Please make selected monitor layout rightmost (or leftmost) first, apply the preferred orientation, then setup correct
monitor order as a mitigation.

- When displayLink-driver debian package is installed first time with GUI application like Synaptic and Secure Boot is
enabled then installation will fail.
How to use DisplayLink Ubuntu driver with UEFI Secure Boot (https://support.displaylink.com/knowledgebase/articles/1181617-how-to-use-displaylink-ubuntu-driver-with-uefi-sec)

I. Future development
======================

Synaptics are open to suggestions and feedback on improving the proposed architecture and will gladly review patches or proposals from the developer community. Please find a current list of areas we identify as requiring attention below.

- In this release, the user mode driver service is running with root permissions. In future versions, we would like to reduce the privilege level required for this process - e.g. by using a separate low-privileged user and a separate group, to ensure the permissions needed for driving DisplayLink screens are as low as possible.

- The communication between the EVDI kernel module and the wrapper libevdi library is not access-controlled or authenticated. This could be improved in future releases, making it harder to compromise the data EVDI is sending and receiving.

- EVDI kernel module driver is currently a platform_driver, for multiple reasons; most importantly because virtual displays are not discoverable, i.e. cannot be enumerated at the hardware level. EVDI is also a generic device, not tied to any particular kind of device, transport layer or a bus.
