Comment 22 for bug 1955916

Sorry tried what you suggested but didn't work also rebooted just to
make sure. Disconnected and connected it just to show it got detected

dmesg | tail
[   12.333954] Bluetooth: RFCOMM TTY layer initialized
[   12.333961] Bluetooth: RFCOMM socket layer initialized
[   12.333965] Bluetooth: RFCOMM ver 1.11
[  130.282338] usb 1-5: USB disconnect, device number 2
[  133.112366] usb 1-5: new full-speed USB device number 11 using xhci_hcd
[  133.261310] usb 1-5: New USB device found, idVendor=2550,
idProduct=8761, bcdDevice= 2.00
[  133.261324] usb 1-5: New USB device strings: Mfr=1, Product=2,
SerialNumber=3
[  133.261330] usb 1-5: Product: Bluetooth Radio
[  133.261335] usb 1-5: Manufacturer: Realtek
[  133.261339] usb 1-5: SerialNumber: 00E04C239987

hciconfig -a
hci0:    Type: Primary  Bus: USB
    BD Address: 00:E0:4C:19:83:78  ACL MTU: 1021:6  SCO MTU: 255:12
    UP RUNNING
    RX bytes:1641 acl:0 sco:0 events:131 errors:0
    TX bytes:7618 acl:0 sco:0 commands:131 errors:0
    Features: 0xff 0xff 0xff 0xfe 0xdb 0xfd 0x7b 0x87
    Packet type: DM1 DM3 DM5 DH1 DH3 DH5 HV1 HV2 HV3
    Link policy: RSWITCH HOLD SNIFF PARK
    Link mode: SLAVE ACCEPT
    Name: 'pinky'
    Class: 0x1c0104
    Service Classes: Rendering, Capturing, Object Transfer
    Device Class: Computer, Desktop workstation
    HCI Version: 5.1 (0xa)  Revision: 0xb
    LMP Version: 5.1 (0xa)  Subversion: 0x8761
    Manufacturer: Realtek Semiconductor Corporation (93)

hcitool scan
Scanning ...

didn't produce anything and neither did the gui.

lsusb | grep -i bluetooth
Bus 001 Device 011: ID 2550:8761 Realtek Bluetooth Radio

Regards, ..

Op 5/01/2022 om 02:04 schreef Ed:
> The problem is that the USB ID for this chip is not in the btusb module.
> Many people report the same problem elsewhere, though it seems most want
> to try and use a strange module from a random BT dongle manufacturers
> website, which is just crazy. The proper thing to do is to add the USB
> ID to drivers/bluetooth/btusb.c.
>
> However, I am a bit lazy, so instead I just modified the driver in
> place, writing over the ID of another realtek chip with this one (0x2550
> 0x8761), then strip the module to remove the signature:
>
> sudo -s
> cp /lib/modules/`uname -r`/kernel/drivers/bluetooth/btusb.ko btusb.ko.orig
> xxd /lib/modules/`uname -r`/kernel/drivers/bluetooth/btusb.ko | sed 's/ca04 0540/5025 6187/g' | xxd -r > btusb.ko.mod
> strip --strip-debug btusb.ko.mod
> mv btusb.ko.mod /lib/modules/`uname -r`/kernel/drivers/bluetooth/btusb.ko
>
> Don't forget to also download firmware:
>
> wget -O /lib/firmware/rtl_bt/rtl8761b_config.bin https://raw.githubusercontent.com/Realtek-OpenSource/android_hardware_realtek/rtk1395/bt/rtkbt/Firmware/BT/rtl8761b_config
> wget -O /lib/firmware/rtl_bt/rtl8761b_fw.bin https://raw.githubusercontent.com/Realtek-OpenSource/android_hardware_realtek/rtk1395/bt/rtkbt/Firmware/BT/rtl8761b_fw
>
> You have to disable secure boot to load the modified module, if you
> didn't have it disabled already, and reboot. If already disabled you can
> probably just do:
>
> modprobe -r btusb && modprobe btusb
>
> You also need at least kernel 5.8 I believe.
>
> Hopefully the USB ID will be added to the kernel soon, as it's pretty
> silly having to do this!
>