Re: [PATCH v2 1/2] Bluetooth: btusb: Add ASUS USB-BT540 for Realtek 8761CU
From: Paul Menzel
Date: Sun Jul 05 2026 - 05:43:57 EST
Dear Christoph,
Thank you for sending v2.
Am 05.07.26 um 11:28 schrieb cito@xxxxxxxxx:
From: Christoph Zwerschke <cito@xxxxxxxxx>
Add the vendor/product ID (0x0b05, 0x1bef) to the usb_device_id table for
the Realtek RTL8761CU-based ASUS USB-BT540 adapter. It binds via the
generic Bluetooth class today, so BTUSB_REALTEK is never set and the
rtl8761cu firmware is not loaded, leaving the controller non-functional.
With the entry the driver loads rtl_bt/rtl8761cu_fw.bin (already shipped by
linux-firmware) and the adapter works (tested: A2DP and ASHA).
Similar to commit bc597f0cc44f
("Bluetooth: btusb: Add TP-Link UB600 for Realtek 8761BUV").
Device info from /sys/kernel/debug/usb/devices:
T: Bus=01 Lev=01 Prnt=01 Port=01 Cnt=01 Dev#= 22 Spd=12 MxCh= 0
D: Ver= 1.10 Cls=e0(wlcon) Sub=01 Prot=01 MxPS=64 #Cfgs= 1
P: Vendor=0b05 ProdID=1bef Rev= 2.00
S: Manufacturer=Realtek
S: Product=Bluetooth Controller
C:* #Ifs= 2 Cfg#= 1 Atr=e0 MxPwr=100mA
I:* If#= 0 Alt= 0 #EPs= 3 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=81(I) Atr=03(Int.) MxPS= 64 Ivl=1ms
E: Ad=02(O) Atr=02(Bulk) MxPS= 64 Ivl=0ms
E: Ad=82(I) Atr=02(Bulk) MxPS= 64 Ivl=0ms
I:* If#= 1 Alt= 0 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=83(I) Atr=01(Isoc) MxPS= 0 Ivl=1ms
E: Ad=03(O) Atr=01(Isoc) MxPS= 0 Ivl=1ms
I: If#= 1 Alt= 1 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=83(I) Atr=01(Isoc) MxPS= 9 Ivl=1ms
E: Ad=03(O) Atr=01(Isoc) MxPS= 9 Ivl=1ms
I: If#= 1 Alt= 2 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=83(I) Atr=01(Isoc) MxPS= 17 Ivl=1ms
E: Ad=03(O) Atr=01(Isoc) MxPS= 17 Ivl=1ms
I: If#= 1 Alt= 3 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=83(I) Atr=01(Isoc) MxPS= 25 Ivl=1ms
E: Ad=03(O) Atr=01(Isoc) MxPS= 25 Ivl=1ms
I: If#= 1 Alt= 4 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=83(I) Atr=01(Isoc) MxPS= 33 Ivl=1ms
E: Ad=03(O) Atr=01(Isoc) MxPS= 33 Ivl=1ms
I: If#= 1 Alt= 5 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=83(I) Atr=01(Isoc) MxPS= 49 Ivl=1ms
E: Ad=03(O) Atr=01(Isoc) MxPS= 49 Ivl=1ms
I: If#= 1 Alt= 6 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=83(I) Atr=01(Isoc) MxPS= 63 Ivl=1ms
E: Ad=03(O) Atr=01(Isoc) MxPS= 63 Ivl=1ms
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Christoph Zwerschke <cito@xxxxxxxxx>
---
drivers/bluetooth/btusb.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index e9b0b1dcc1d1..c15c7ab5bd2e 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -856,6 +856,10 @@ static const struct usb_device_id quirks_table[] = {
{ USB_DEVICE(0x37ad, 0x0600), .driver_info = BTUSB_REALTEK |
BTUSB_WIDEBAND_SPEECH },
+ /* Additional Realtek 8761CU Bluetooth devices */
+ { USB_DEVICE(0x0b05, 0x1bef), .driver_info = BTUSB_REALTEK |
+ BTUSB_WIDEBAND_SPEECH },
+
/* Additional Realtek 8821AE Bluetooth devices */
{ USB_DEVICE(0x0b05, 0x17dc), .driver_info = BTUSB_REALTEK },
{ USB_DEVICE(0x13d3, 0x3414), .driver_info = BTUSB_REALTEK },
Reviewed-by: Paul Menzel <pmenzel@xxxxxxxxxxxxx>
Kind regards,
Paul