Public bug reported: [Impact] On Intel CML desktop, there's no HDMI output when the cable is not connected pre-boot.
[Fix] Properly handle lane polarity so the driver can write different values to the register to enable the port. [Test] 1. Boot with DP display. 2. Connect HDMI under GNOME desktop. 3. No picture on HDMI monitor. With the fix applied, the issue is resolved. [Where problems could occur] If the BIOS VBT table is not correct, which did happen in the pase, this fix may break those ports. ** Affects: hwe-next Importance: Undecided Status: New ** Affects: linux (Ubuntu) Importance: Medium Status: Confirmed ** Affects: linux-oem-5.10 (Ubuntu) Importance: Undecided Status: Invalid ** Affects: linux (Ubuntu Focal) Importance: Undecided Status: Won't Fix ** Affects: linux-oem-5.10 (Ubuntu Focal) Importance: Medium Status: Confirmed ** Affects: linux (Ubuntu Hirsute) Importance: Medium Status: Confirmed ** Affects: linux-oem-5.10 (Ubuntu Hirsute) Importance: Undecided Status: Invalid ** Tags: oem-priority originate-from-1908030 stella ** Also affects: linux-oem-5.10 (Ubuntu) Importance: Undecided Status: New ** Also affects: linux (Ubuntu Hirsute) Importance: Undecided Status: New ** Also affects: linux-oem-5.10 (Ubuntu Hirsute) Importance: Undecided Status: New ** Also affects: linux (Ubuntu Focal) Importance: Undecided Status: New ** Also affects: linux-oem-5.10 (Ubuntu Focal) Importance: Undecided Status: New ** Changed in: linux (Ubuntu Focal) Status: New => Won't Fix ** Changed in: linux (Ubuntu Hirsute) Status: New => Confirmed ** Changed in: linux (Ubuntu Hirsute) Importance: Undecided => Medium ** Changed in: linux-oem-5.10 (Ubuntu Focal) Status: New => Confirmed ** Changed in: linux-oem-5.10 (Ubuntu Focal) Importance: Undecided => Medium ** Changed in: linux-oem-5.10 (Ubuntu Hirsute) Status: New => Invalid -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1924238 Title: Fix no picture from HDMI when it's plugged after boot Status in HWE Next: New Status in linux package in Ubuntu: Confirmed Status in linux-oem-5.10 package in Ubuntu: Invalid Status in linux source package in Focal: Won't Fix Status in linux-oem-5.10 source package in Focal: Confirmed Status in linux source package in Hirsute: Confirmed Status in linux-oem-5.10 source package in Hirsute: Invalid Bug description: [Impact] On Intel CML desktop, there's no HDMI output when the cable is not connected pre-boot. [Fix] Properly handle lane polarity so the driver can write different values to the register to enable the port. [Test] 1. Boot with DP display. 2. Connect HDMI under GNOME desktop. 3. No picture on HDMI monitor. With the fix applied, the issue is resolved. [Where problems could occur] If the BIOS VBT table is not correct, which did happen in the pase, this fix may break those ports. To manage notifications about this bug go to: https://bugs.launchpad.net/hwe-next/+bug/1924238/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp