bluetooth issues since kernel 6.4 - not discovering other bt devices - /linux/drivers/bluetooth/btusb.c

[Tomasz Moń]

On Tue, 2023-10-03 at 14:42 +0200, Erik Dobák wrote:
> Sure here you go:
> 
> # lsusb -d 04c5:1670 -v
> 
> Bus 001 Device 004: ID 04c5:1670 Fujitsu, Ltd Bluetooth Radio
> Device Descriptor:
>   bLength                18
>   bDescriptorType         1
>   bcdUSB               1.00
>   bDeviceClass          224 Wireless
>   bDeviceSubClass         1 Radio Frequency
>   bDeviceProtocol         1 Bluetooth
>   bMaxPacketSize0        64
>   idVendor           0x04c5 Fujitsu, Ltd
>   idProduct          0x1670
>   bcdDevice            0.00
>   iManufacturer           1 Realtek
>   iProduct                2 Bluetooth Radio
>   iSerial                 3 00e04c000001
>   bNumConfigurations      1
>   Configuration Descriptor:
>     bLength                 9
>     bDescriptorType         2
>     wTotalLength       0x00b1
>     bNumInterfaces          2
>     bConfigurationValue     1
>     iConfiguration          0
>     bmAttributes         0xe0
>       Self Powered
>       Remote Wakeup
>     MaxPower              500mA
>     Interface Descriptor:
>       bLength                 9
>       bDescriptorType         4
>       bInterfaceNumber        0
>       bAlternateSetting       0
>       bNumEndpoints           3
>       bInterfaceClass       224 Wireless
>       bInterfaceSubClass      1 Radio Frequency
>       bInterfaceProtocol      1 Bluetooth
>       iInterface              4 Bluetooth Radio

I have no idea why you referred to my commits, i.e. c13380a55522
("Bluetooth: btusb: Do not require hardcoded interface numbers") later
fixed by eaac6e223a0d ("Bluetooth: btusb: Fix bluetooth on Intel
Macbook 2014") in the first place.

BTUSB_IFNUM_2 is not even getting set for this device and therefore the
patches have no impact on your issue. If you were affected, like the
Intel Macbook 2014 was, then bear in mind that the issue would manifest
as btusb driver not even binding to the device. From your emails
however it appears that the issue is something different.

I honestly don't think it has anything to do with my patches. If you
know a Linux version where your bluetooth device works, then the next
step would be to bisect to find the first bad commit.

Best Regards,
Tomasz Moń