** 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. + https://lore.kernel.org/lkml/[email protected]/T/#u [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 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 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. MachineType: Alienware Alienware 16 Aurora AC16250 ProcFB: 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 RfKill: 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
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2145164 Title: Bluetooth device (MT7925) not detected on USB bus with linux-oem-6.17 To manage notifications about this bug go to: https://bugs.launchpad.net/hwe-next/+bug/2145164/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
