Hi Larry,I agree. Not only BT, but also wifi in RTL8723AU has caused me a lot of trouble.
these Realtek devices are causing the most messy setup in a generic driver. And Bluetooth USB support has been really clean and simple for the last 10 years. I really wonder how many ways this gets done wrong before someone gets a clue and gets this right. At the end of the day this USB transport is 15 years old.Something changed in recent kernels, and the generic USB transport entries do not seem to be recognized in the case where a wifi and BT device share a single USB ID. As the OP's tablet has such a case, I suggest that 0bda line be accepted, but not the others. If I had a computer with an RTL8723AU, I would have a chance at debugging what changed, but sadly, that is not the case.In 'commit a2698a9bf9b0 ("Bluetooth: btusb: Add RealtekI highly doubt these are needed. There is a generic entry for an USB transport that is already covering these.
8723A/8723B/8761A/8821A support"), support of some Realtek
devices was added to the Generic Bluetooth USB driver in kernel.
However, these devices are not in the module device table of
btusb.ko, so the kernel wouldn't probe them at all.
To fix this, add four entries in the device table btusb_table,
based on code from <https://github.com/lwfinger/rtl8723au_bt>
('new' branch).
This enables bluetooth support in the Lenovo Ideapad Yoga 13
which has RTL8723AU USB device, with product ID 0bda:1724.
Signed-off-by: Xi Ruoyao <xry111@xxxxxxxxxxx>
---
drivers/bluetooth/btusb.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 3c10d4d..dd87623 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -148,6 +148,12 @@ static const struct usb_device_id btusb_table[] = {
{ USB_DEVICE(0x8087, 0x0a5a),
.driver_info = BTUSB_INTEL_BOOT | BTUSB_BROKEN_ISOC },
+ /* Realtek Bluetooth */
+ { USB_VENDOR_AND_INTERFACE_INFO(0x0bda, 0xe0, 0x01, 0x01) },
+ { USB_VENDOR_AND_INTERFACE_INFO(0x0bd5, 0xe0, 0x01, 0x01) },
+ { USB_VENDOR_AND_INTERFACE_INFO(0x13d3, 0xe0, 0x01, 0x01) },
+ { USB_VENDOR_AND_INTERFACE_INFO(0x0489, 0xe0, 0x01, 0x01) },
+
Anyway, for obvious reasons the content of /sys/kernel/debug/usb/devices should be included here so that someone can actually look at how the USB endpoints are configured.The contents about my RTL8723AU is here:
RegardsWe can see, since in RTL8723AU the wifi and BT share a single USB ID, the device
Marcel