From nobody Sat Sep 26 07:14:46 2026 Received: from mail-yw1-f170.google.com (mail-yw1-f170.google.com [209.85.128.170]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EA9474F30EC for ; Thu, 3 Sep 2026 17:03:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.170 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788455010; cv=none; b=ggv0v76NNWEoWn6cwMIC3tfYbPcYuOSAP4bo6xWkxHVJ2hkVU8Du4NKMI4nbyyhf8T+ACd8lUlbaOTMl0JgJ9i7Vta6g8s1Se6s7vFWVnlmmcOhM5pC8U2jB0hlgzGMF4ap5ibb/IESYVRYOgumHFG7DNJtO+j+Zu7H71UDkWFs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788455010; c=relaxed/simple; bh=6vLgwFypI9R6E48HnmbFTXCQiSQpFbanDrb/YELuqEs=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=Vvws1iwEXTvVQJeu6huUus2b30DyzKqxyZHIoodOYIChWTlRsH/ANwc6Y9C/tnR7axAsR5TPiyzOMpOu2dnhe767lbv0aMtqZ4fRTrxsIodlvDCksaBg3CW+xpMo3+FQSHDR5uy7MP8qUksbmwnt6zRybtt5eVHgUI3ucwYMeGw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=QQYKnSVO; arc=none smtp.client-ip=209.85.128.170 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="QQYKnSVO" Received: by mail-yw1-f170.google.com with SMTP id 00721157ae682-836c4474028so1661757b3.0 for ; Thu, 03 Sep 2026 10:03:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1788455008; x=1789059808; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to:content-type; bh=CstuSRSoRYjDy3SQPB3JE0tK/DdVcQaXoQui8YlYnzY=; b=QQYKnSVOlORU22HAtJfuNVl4iQiCljkEKWs/8txAonTMfEjSWpKVbcC1PEJ4X+hCaU XZ+MbMr2TtDnJ4Xt0kQX3W45dL09ERr0eilP00Eu+VRb31O5sxiRSw9YX3hZspdInT/v x9utrbLEXuB2ucQScMLqbEXH4XH0LS84nZI88VOGP1VBYyB+S4hZ5+Oc7Rxd4NCd1RoX d/tX0Gi3dFPtCF3ckZqv/GJ96akyWVrMVvg+6wKydPB3xovIdaxlpBSucPoMBdkUwsFZ lKjRMm6tHJ/5Flxdi9A4vj8a41St0A130csA9T8i1YJOoGNBf5kZhSTNDUxYB/F/jbLo /zBQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1788455008; x=1789059808; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=CstuSRSoRYjDy3SQPB3JE0tK/DdVcQaXoQui8YlYnzY=; b=DjWHluUbd+reamSKPNx2nyPEoSOJ06I+abmdcTdHWF0ZN2vgupkd4u3Y/qqyUO4lf7 uv15iU5m5VZWdVqtRsvAyQ16zqGVpNwt5OMoJPGXr4IiNhlxkF7S6Zf5DfI4/lKCjFOW 2qlnff1fiXhLmhIQxf4ikBkdeO5FukDlXfy62dQkM6sdu0cHHg0xa4NmDnVErJJZDGHC dI7Pnk20MPT8ueezmD0mdR1e56RSZ6fdjEGvvN8lhAREibp/IbOgHZwxP+H2eF38luoe P01sLFL5RTdWpzpk1xKtpxeIka0jhBC/hG7VyY+gp01dTu42Q0CerEhyKG9Bwo2zhxck MM0Q== X-Forwarded-Encrypted: i=1; AKwUvBwtQPCpDwFVyd4AImBjroFfYLqeCRUWdXZFmhkC8UHTZCz/wT+BA3BEETLxQODivBz6gDlk3NgNVMnoxxo=@vger.kernel.org X-Gm-Message-State: AFuF++l6264y9KjdoRZd1Xe2nJ+8jWoyGEYO0mt7f5nm2VphuLB/D5E9 JuTuQR3fzeqTbDckL0AXrKIAC9y69fj5A7NIg7YI9zsSaJZGwbBMo9Ic X-Gm-Gg: AYBFou35I3nhvNex3UaOFCQGwanRYsjexUU43fV6LGEBBCge97cn1uX7qXR2nDwqoSP PqptaMg8bfRLQQn+KoNfPSJhvOhgeeQtVQgWLhxG1cYLLkYSuXkTQTizqhPh6qbmj5s05QnCxWa 7iZw5HiNNzgFI5idalNs4V7LIHwD29KYcYPVSQwHXC2Cylj1p5zFdW3/Ks4f1i6av2qulIzLjkA cLMCk0ZCoqJrsEpm0CRgOVDGLUOfsKFeW+VAMHJ62gfAtuSLCkeim7cEW5/G8v0s7TafPi7ki1t hAg5Xiq8b1Ivov5ATykl+/J39IYrIoVr+z1Mjf8gs/UAwKoctSwvmpRTyMikQMV4cg0dMbcXg/A 2JrGVZtLnJ/HPtdszge2jtgGuHahVr7w19oQOOXkBo1Ydw3mDlEOXYhVpJPpYbwXLxDgKN02kDT cRj3AmjHI1Qwrwlzuve+pJIOgYSQIziCIZ2RcQJzSHXozZKgfhLY7zHr2dZzFjepQW5Q== X-Received: by 2002:a05:690c:6605:b0:845:ddf4:a399 with SMTP id 00721157ae682-8712390b41dmr2299217b3.11.1788455007588; Thu, 03 Sep 2026 10:03:27 -0700 (PDT) Received: from Beast ([2600:1702:8265:324f:c600:425a:f388:aa8b]) by smtp.gmail.com with ESMTPSA id 00721157ae682-86c1784382esm44343537b3.25.2026.09.03.10.03.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 03 Sep 2026 10:03:26 -0700 (PDT) From: Aritra Das To: Marcel Holtmann , Luiz Augusto von Dentz Cc: linux-bluetooth@vger.kernel.org, linux-kernel@vger.kernel.org, Aritra Das Subject: [PATCH] Bluetooth: btusb: Add USB ID 13d3:3556 for RTL8821CE Date: Thu, 3 Sep 2026 10:03:22 -0700 Message-ID: <20260903170322.47004-1-aritra.rohit2003@gmail.com> X-Mailer: git-send-email 2.55.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The onboard Realtek RTL8821CE combo card on the ASUS PRIME B550-PLUS AC-HES presents its Bluetooth function as USB ID 13d3:3556. This ID is missing from quirks_table, so btusb matches the device only through the generic Bluetooth class entry in btusb_table and driver_info stays zero. BTUSB_REALTEK is therefore never set, btrtl never runs, and the controller keeps executing its on-chip ROM firmware instead of loading rtl_bt/rtl8821c_fw.bin and rtl_bt/rtl8821c_config.bin. In that state BLE HID peripherals are unusable. A HHKB Hybrid keyboard pairs and enumerates as a HID device, then the link drops within 10-30 seconds, repeatedly. The same keyboard is stable on the same host under other operating systems. Adding the ID lets btusb run the Realtek setup path: Bluetooth: hci0: RTL: examining hci_ver=3D08 hci_rev=3D000c lmp_ver=3D08 = lmp_subver=3D8821 Bluetooth: hci0: RTL: rom_version status=3D0 version=3D1 Bluetooth: hci0: RTL: loading rtl_bt/rtl8821c_fw.bin Bluetooth: hci0: RTL: loading rtl_bt/rtl8821c_config.bin Bluetooth: hci0: RTL: cfg_sz 10, total sz 34926 Bluetooth: hci0: RTL: fw version 0x75b8f098 With the firmware loaded the same keyboard has stayed connected for over 11 hours without a single drop. Device descriptor: T: Bus=3D01 Lev=3D01 Prnt=3D01 Port=3D04 Cnt=3D02 Dev#=3D 2 Spd=3D12 Mx= Ch=3D 0 D: Ver=3D 1.10 Cls=3De0(wlcon) Sub=3D01 Prot=3D01 MxPS=3D64 #Cfgs=3D 1 P: Vendor=3D13d3 ProdID=3D3556 Rev=3D01.10 S: Manufacturer=3DRealtek=20 S: Product=3DBluetooth Radio=20 S: SerialNumber=3D00e04c000001 C: #Ifs=3D 2 Cfg#=3D 1 Atr=3De0 MxPwr=3D500mA I: If#=3D 0 Alt=3D 0 #EPs=3D 3 Cls=3De0(wlcon) Sub=3D01 Prot=3D01 Driver= =3Dbtusb E: Ad=3D02(O) Atr=3D02(Bulk) MxPS=3D 64 Ivl=3D0ms E: Ad=3D81(I) Atr=3D03(Int.) MxPS=3D 16 Ivl=3D1ms E: Ad=3D82(I) Atr=3D02(Bulk) MxPS=3D 64 Ivl=3D0ms I: If#=3D 1 Alt=3D 0 #EPs=3D 2 Cls=3De0(wlcon) Sub=3D01 Prot=3D01 Driver= =3Dbtusb E: Ad=3D03(O) Atr=3D01(Isoc) MxPS=3D 0 Ivl=3D1ms E: Ad=3D83(I) Atr=3D01(Isoc) MxPS=3D 0 Ivl=3D1ms Signed-off-by: Aritra Das --- drivers/bluetooth/btusb.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c index 03039ce..0424898 100644 --- a/drivers/bluetooth/btusb.c +++ b/drivers/bluetooth/btusb.c @@ -511,6 +511,8 @@ static const struct usb_device_id quirks_table[] =3D { BTUSB_WIDEBAND_SPEECH }, { USB_DEVICE(0x13d3, 0x3533), .driver_info =3D BTUSB_REALTEK | BTUSB_WIDEBAND_SPEECH }, + { USB_DEVICE(0x13d3, 0x3556), .driver_info =3D BTUSB_REALTEK | + BTUSB_WIDEBAND_SPEECH }, { USB_DEVICE(0x13d3, 0x3558), .driver_info =3D BTUSB_REALTEK | BTUSB_WIDEBAND_SPEECH }, =20 base-commit: 6696072ffe07205255cf83621a95a1aa2f9f6e62