From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 99DC42D73B5 for ; Sun, 18 Jan 2026 10:11:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768731103; cv=none; b=oDWG0H74w5KrSf/phr13jOcaWy94Iixy1NltBWXJ4PKRttZmR49rfOpY/j61VUBuAKhsPtA6TNVSU4NKOqBgFX75V6Y8GD0DXyqxOburIpsuoimjdugjIWlNTsLYYDw+fwNQJxLNjAxZad/nCt9QxSGBa77Vvszw5pN/rX6Qjr8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768731103; c=relaxed/simple; bh=QRJDVO7ul0pMJI9rkaq0mvjAsTvDV8JJ1Mowtb5IoM0=; h=From:To:Subject:Date:Message-ID:Content-Type:MIME-Version; b=CLzcH/B6H0jOkYgmFlM/gW+I/FGebctd+RohjudKbQ/BRCGorRn5w07pCxRAk71tK2EGhfLUb2ZsAqBeS32YmYGkTNBAqBnU98GqTMl5aJiJwQfhPWy6rBtyGSsW3PiAvU+ETF+X49U9+B5t6LYOqsxNZ2iScLCjahr4erZrFZs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=M8yHkOTB; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="M8yHkOTB" Received: by smtp.kernel.org (Postfix) with ESMTPS id 457CCC19425 for ; Sun, 18 Jan 2026 10:11:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1768731103; bh=QRJDVO7ul0pMJI9rkaq0mvjAsTvDV8JJ1Mowtb5IoM0=; h=From:To:Subject:Date:From; b=M8yHkOTBV62LebYnnVIFo9bdnrxhCHmHwgqKeZdJ04I58eYRi3MksEMuIVuF46gCS brjoD/z4ojBw9CsJyawYAMAykhZ+dClKWEzjI5R9maCXMwm2jp70no1eJD0pdmoew8 e1wDZ48OnWO9o2Hjo3wJA2vD2mO71FEJn8voN4dLTGzDXe51giEog0m6epV6+kOvl0 Xeb5PCRk4jeFRxcjKTaOTpLj8fv6gvyxdPpdutmkHfbF9yG1jbRTIXEJDGABsIEeju tfxGqnBQHCtK9MH1RLnl4ts7MjNCobszvSWibhR5Ue/xkOyNuKPqzl1qUYZiWxeYW4 roOPz0beOmdVQ== Received: by aws-us-west-2-korg-bugzilla-1.web.codeaurora.org (Postfix, from userid 48) id 3337DC4160E; Sun, 18 Jan 2026 10:11:43 +0000 (UTC) From: bugzilla-daemon@kernel.org To: linux-bluetooth@vger.kernel.org Subject: [Bug 220990] New: hci_uart_bcm: BCM43341 on Intel Atom (serdev) fails init (MTU 0:0, DOWN RAW) Date: Sun, 18 Jan 2026 10:11:42 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Drivers X-Bugzilla-Component: Bluetooth X-Bugzilla-Version: 2.5 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: bugzilla@emircanerkul.com X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: linux-bluetooth@vger.kernel.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter cf_regression attachments.created Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated Precedence: bulk X-Mailing-List: linux-bluetooth@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 https://bugzilla.kernel.org/show_bug.cgi?id=3D220990 Bug ID: 220990 Summary: hci_uart_bcm: BCM43341 on Intel Atom (serdev) fails init (MTU 0:0, DOWN RAW) Product: Drivers Version: 2.5 Hardware: Intel OS: Linux Status: NEW Severity: normal Priority: P3 Component: Bluetooth Assignee: linux-bluetooth@vger.kernel.org Reporter: bugzilla@emircanerkul.com Regression: No Created attachment 309211 --> https://bugzilla.kernel.org/attachment.cgi?id=3D309211&action=3Dedit fix for llm models I applied solution in https://bugzilla.kernel.org/show_bug.cgi?id=3D100461 But now it do not detect my devices. =E2=9D=AF bluetoothctl=20=20=20=20=20=20=20=20=20=20=20=20=20=20 hci0 new_settings: powered bondable ssp br/edr le secure-conn=20 Agent registered [CHG] Controller CD:74:2E:6E:CD:FA Pairable: yes [bluetoothctl]> power on Changing power on succeeded [bluetoothctl]> discover on Invalid command in menu main: discover Use "help" for a list of available commands in a menu. Use "menu " if you want to enter any submenu. Use "back" if you want to return to menu main. [bluetoothctl]> he [bluetoothctl]> scan on SetDiscoveryFilter success hci0 type 7 discovering on Discovery started [CHG] Controller CD:74:2E:6E:CD:FA Discovering: yes hci0 type 7 discovering off hci0 type 7 discovering on hci0 type 7 discovering off hci0 type 7 discovering on hci0 type 7 discovering off --- ISSUE SOVED WITH 100461 --- 1. Hardware Description Device: Intel StickPC (Atom x5-Z8300 "Cherry Trail" / "Bay Trail" platform) Bluetooth/WiFi Chip: Broadcom BCM43341B0 (Combo Chip) ACPI ID: BCM2E95 Interface: Intel HS-UART connected via serdev (serial0-0) Connection: UART (not USB) 2. System Information OS: Debian 13 (Trixie) Kernel: 6.12.63+deb13-amd64 (Upstream 6.12 series) BlueZ Version: 5.82 Firmware: BCM43341B0.hcd (Size: 41,333 bytes). Verified identical to working Windows 10 driver firmware. 3. Issue Description The Bluetooth controller is detected, and the hci_uart_bcm driver successfu= lly loads the specific firmware patch (build 0176). However, immediately after firmware loading, the device remains in a DOWN RAW state with MTU 0:0. Attempting to bring the device up fails with "Operation not supported". The device never registers with the BlueZ management layer (btmgmt info is empt= y). It appears the HCI_QUIRK_RAW_DEVICE flag (set by hci_serdev.c during setup)= is never cleared, or the bcm_setup function completes but the driver fails to transition the device to a fully operational state. 4. Steps to Reproduce Boot minimal Debian 13 with Kernel 6.12 on Intel Atom Z8300 device with BCM43341. Ensure correct firmware BCM43341B0.hcd is in /lib/firmware/brcm/. Check hciconfig -a. 5. Logs & Output hciconfig -a hci0: Type: Primary Bus: UART BD Address: 43:34:1B:00:1F:AC ACL MTU: 0:0 SCO MTU: 0:0 DOWN RAW=20 RX bytes:2220 acl:0 sco:0 events:238 errors:0 TX bytes:41654 acl:0 sco:0 commands:238 errors:0 Features: 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 Packet type: DM1 DH1 HV1=20 Link policy:=20 Link mode: PERIPHERAL ACCEPT (Note: Address is the default Broadcom address, indicating configuration di= dn't finish) dmesg (Filtered) [ 10.438792] hci_uart_bcm serial0-0: supply vbat not found, using dummy regulator [ 10.438896] hci_uart_bcm serial0-0: supply vddio not found, using dummy regulator ... [ 10.888224] Bluetooth: hci0: BCM: chip id 82 [ 10.902831] Bluetooth: hci0: BCM43341B0 [ 10.902851] Bluetooth: hci0: BCM43341B0 (002.001.014) build 0000 [ 10.929324] Bluetooth: hci0: BCM43341B0 'brcm/BCM43341B0.hcd' Patch ... [ 11.551231] Bluetooth: hci0: BCM43341B0 37.4 MHz Class 1 WLBGA iTR [ 11.551245] Bluetooth: hci0: BCM43341B0 (002.001.014) build 0176 [ 11.552167] Bluetooth: hci0: BCM: Using default device address (43:34:1b:00:1f:ac) (Note: Firmware loads successfully - build number changes from 0000 to 0176. But then it stops.) btmgmt info Index list with 0 items Attempting to bring up # hciconfig hci0 up Can't init device hci0: Operation not supported (95) 6. What Was Tried (Workarounds) Windows Firmware: Replaced Linux firmware with verified working Windows 10 driver (BCM43341B0_002.001.014.0122.0176.hcd). Result: Identical behavior. Firmware load OK, Init fail. Kernel Parameters: Added intel_idle.max_cstate=3D1 to prevent BayTrail deep= sleep issues. Result: No change. btattach: Attempted manual btattach but failed because serdev framework cla= ims the UART (serial0-0) and does not expose a /dev/ttyS* node to userspace even after unbinding the driver. 7. Suspected Root Cause Regression in drivers/bluetooth/hci_bcm.c or hci_serdev.c on Kernel 6.12 regarding the handling of HCI_QUIRK_RAW_DEVICE for ACPI-enumerated BCM devi= ces. The setup phase (firmware load) works, but the transition to operational mo= de is missing. --=20 You may reply to this email to add a comment. You are receiving this mail because: You are the assignee for the bug.=