** Tags added: jira-somerville-4265 oem-priority somerville
** Also affects: linux (Ubuntu)
Importance: Undecided
Status: New
** Also affects: linux (Ubuntu Questing)
Importance: Undecided
Status: New
** Also affects: linux-oem-6.17 (Ubuntu Questing)
Importance: Undecided
Status: New
** Also affects: linux (Ubuntu Resolute)
Importance: Undecided
Status: New
** Also affects: linux-oem-6.17 (Ubuntu Resolute)
Importance: Undecided
Status: Confirmed
** Also affects: linux (Ubuntu Noble)
Importance: Undecided
Status: New
** Also affects: linux-oem-6.17 (Ubuntu Noble)
Importance: Undecided
Status: New
** Changed in: linux (Ubuntu Noble)
Status: New => Invalid
** Changed in: linux (Ubuntu Questing)
Status: New => In Progress
** Changed in: linux (Ubuntu Resolute)
Status: New => In Progress
** Changed in: linux-oem-6.17 (Ubuntu Noble)
Status: New => In Progress
** Changed in: linux-oem-6.17 (Ubuntu Questing)
Status: New => Invalid
** Changed in: linux-oem-6.17 (Ubuntu Resolute)
Status: Confirmed => Invalid
** Changed in: linux (Ubuntu Questing)
Assignee: (unassigned) => AceLan Kao (acelankao)
** Changed in: linux (Ubuntu Resolute)
Assignee: (unassigned) => AceLan Kao (acelankao)
** Changed in: linux-oem-6.17 (Ubuntu Noble)
Assignee: (unassigned) => AceLan Kao (acelankao)
** Description changed:
+ SRU Justification
+
+ [Impact]
+ MT7925 Bluetooth on Dell systems fails to enumerate at boot when the
+ BT_RST GPIO is stuck low. The device never comes up and Bluetooth is
+ unavailable. The only recovery is a full mechanical power-off (G3 cycle).
+
+ Error log:
+ [ 6.813942] usb 3-10: device descriptor read/64, error -110
+ [ 22.685978] usb 3-10: device descriptor read/64, error -110
+ [ 28.317963] usb 3-10: device descriptor read/64, error -110
+ [ 44.189949] usb 3-10: device descriptor read/64, error -110
+ [ 44.189960] usb usb3-port10: unable to enumerate USB device
+
+ Warm reboots and S5 sleep do not clear the stuck GPIO state. Hits 100%
+ on affected hardware once the GPIO is stuck.
+
+ [Fix]
+ Add usb_acpi_port_prr_reset() to drivers/usb/core/usb-acpi.c. When a
+ USB port has an ACPI _PRR method, the function calls _RST on the
+ returned power resource to toggle the hardware reset line.
+
+ Wire it into hub_port_connect() during the mid-retry VBUS power-cycle:
+ call _PRR._RST while VBUS is off so the GPIO pulse completes before the
+ device gets power. After VBUS comes back on, sleep 100 ms (per USB 2.0
+ spec §7.1.7.3 Fig. 7-29) when _RST succeeded, because
+ hub_power_on_good_delay() has no minimum floor and can return as little
+ as 20 ms on xHCI root hubs.
+
+ Not yet upstream. Patch submitted for upstream review.
+
+ [Test Plan]
+ Trigger the stuck-GPIO condition (G3 cycle on affected Dell hardware to
+ put the system in a normal state, then warm reboot to reproduce).
+
+ Without patch:
+ - dmesg shows repeated "device descriptor read/64, error -110"
+ - Bluetooth unavailable; recovery requires G3 cycle
+
+ With patch:
+ - dmesg shows "attempt power cycle" followed by successful enumeration
+ - Bluetooth comes up without any manual intervention
+
+ Expected dmesg with patch:
+ [ 44.294065] usb usb3-port10: attempt power cycle
+ [ 44.872709] usb 3-10: new high-speed USB device number 6 using xhci_hcd
+ [ 44.888293] usb 3-10: New USB device found, idVendor=0489, idProduct=e139,
bcdDevice= 1.00
+ [ 44.888318] usb 3-10: Manufacturer: MediaTek Inc.
+
+ [Where problems could occur]
+ Could affect USB hub port handling in drivers/usb/core/hub.c and
+ usb-acpi.c.
+
+ usb_acpi_port_prr_reset() is a no-op on ports with no ACPI _PRR method,
+ so non-affected hardware should be unaffected. If the ACPI method
+ evaluation returns an unexpected object type or the _RST call hangs, the
+ hub_port_connect() retry loop could stall or log spurious errors.
+
+ The 100 ms sleep is conditional on _RST succeeding (prr_reset == 0), so
+ it does not add latency to ports without _PRR.
+
+ ==================================================================
+
Dell machine with MediaTek MT7925 is missing Bluetooth functionality
after upgrading to linux-oem-24.04c 6.17.0-1014.14 and linux-firmware
20240318.git3b128b60-0ubuntu2.26.
The Bluetooth is not listed in lsusb or rfkill list. This causes the
bluetooth/detect test to fail.
[Reproduce Steps]
1. Install Ubuntu Noble on the DUT
2. Upgrade to kernel linux-oem-6.17.0-1012-oem and linux-firmware
version 0ubuntu2.26.
3. Reboot
4. Run lsusb | grep -i bluetooth or rfkill list.
Expected Result:
Bluetooth device is listed and rfkill shows a Bluetooth service.
Actual Result:
No Bluetooth device is detected on the USB bus.
[Affected Machines]
https://certification.canonical.com/hardware/202412-36068/
https://certification.canonical.com/hardware/202412-36070/
https://certification.canonical.com/hardware/202504-36588/
[Failure Rate]
3/3
ProblemType: Bug
DistroRelease: Ubuntu 24.04
Package: linux-image-6.17.0-1014-oem 6.17.0-1014.14
ProcVersionSignature: Ubuntu 6.17.0-1014.14-oem 6.17.13
Uname: Linux 6.17.0-1014-oem x86_64
ApportVersion: 2.28.1-0ubuntu3.8
Architecture: amd64
AudioDevicesInUse:
- USER PID ACCESS COMMAND
- /dev/snd/controlC1: ubuntu 1618 F.... wireplumber
- /dev/snd/controlC0: ubuntu 1618 F.... wireplumber
- /dev/snd/seq: ubuntu 1614 F.... pipewire
+ USER PID ACCESS COMMAND
+ /dev/snd/controlC1: ubuntu 1618 F.... wireplumber
+ /dev/snd/controlC0: ubuntu 1618 F.... wireplumber
+ /dev/snd/seq: ubuntu 1614 F.... pipewire
CasperMD5CheckMismatches: ./casper/initrd ./casper/vmlinuz
./casper/minimal.standard.live.hotfix.manifest
./casper/minimal.standard.live.hotfix.size ./casper/minimal.standard.live.size
./casper/minimal.manifest ./casper/minimal.standard.manifest
./casper/minimal.standard.size ./casper/minimal.hotfix.size
./casper/minimal.standard.live.hotfix.squashfs
./casper/minimal.standard.hotfix.squashfs ./casper/minimal.standard.hotfix.size
./casper/minimal.hotfix.squashfs ./casper/minimal.standard.live.manifest
./casper/minimal.size ./boot/grub/grub.cfg
CasperMD5CheckResult: fail
Date: Mon Mar 23 02:24:00 2026
DistributionChannelDescriptor:
- # This is the distribution channel descriptor for Ubuntu 24.04 for Dell
- # For more information see
http://wiki.ubuntu.com/DistributionChannelDescriptor
- canonical-oem-somerville-noble-oem-24.04b-proposed-20250604-520
+ # This is the distribution channel descriptor for Ubuntu 24.04 for Dell
+ # For more information see
http://wiki.ubuntu.com/DistributionChannelDescriptor
+ canonical-oem-somerville-noble-oem-24.04b-proposed-20250604-520
InstallationDate: Installed on 2026-03-18 (5 days ago)
InstallationMedia: Ubuntu OEM 24.04.2 LTS "Noble Numbat" - Release amd64
(20250603)
IwConfig:
- lo no wireless extensions.
-
- enp4s0 no wireless extensions.
-
- wlp3s0 no wireless extensions.
+ lo no wireless extensions.
+
+ enp4s0 no wireless extensions.
+
+ wlp3s0 no wireless extensions.
MachineType: Alienware Alienware 16 Aurora AC16250
ProcFB:
- 0 i915drmfb
- 1 nvidia-drmdrmfb
+ 0 i915drmfb
+ 1 nvidia-drmdrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-6.17.0-1014-oem
root=UUID=f006ce77-5d42-4984-bedd-47f9bb0fb8d5 ro quiet splash vt.handoff=7
RelatedPackageVersions:
- linux-restricted-modules-6.17.0-1014-oem N/A
- linux-backports-modules-6.17.0-1014-oem N/A
- linux-firmware 20240318.git3b128b60-0ubuntu2.26
+ linux-restricted-modules-6.17.0-1014-oem N/A
+ linux-backports-modules-6.17.0-1014-oem N/A
+ linux-firmware 20240318.git3b128b60-0ubuntu2.26
RfKill:
- 0: phy0: Wireless LAN
- Soft blocked: yes
- Hard blocked: no
+ 0: phy0: Wireless LAN
+ Soft blocked: yes
+ Hard blocked: no
SourcePackage: linux-oem-6.17
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 04/11/2025
dmi.bios.release: 1.2
dmi.bios.vendor: Alienware
dmi.bios.version: 1.2.0
dmi.board.name: 0V901B
dmi.board.vendor: Alienware
dmi.board.version: D02
dmi.chassis.type: 10
dmi.chassis.vendor: Alienware
dmi.ec.firmware.release: 1.2
dmi.modalias:
dmi:bvnAlienware:bvr1.2.0:bd04/11/2025:br1.2:efr1.2:svnAlienware:pnAlienware16AuroraAC16250:pvr:rvnAlienware:rn0V901B:rvrD02:cvnAlienware:ct10:cvr:sku0D35:
dmi.product.family: Alienware
dmi.product.name: Alienware 16 Aurora AC16250
dmi.product.sku: 0D35
dmi.sys.vendor: Alienware
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https://bugs.launchpad.net/bugs/2145164
Title:
Bluetooth device (MT7925) not detected on USB bus with linux-oem-6.17
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