Bluetooth: btrtl: fix RTL8761B/BU broken LE extended scan

RTL8761B and RTL8761BU devices report HCI version 5.1 but do not
support the LE Extended Scan commands. This causes repeated failures
with Opcode 0x2042 (LE Set Extended Scan Parameters) returning -EBUSY
when BlueZ attempts extended scanning while a connection is active.

Set HCI_QUIRK_BROKEN_EXT_SCAN for CHIP_ID_8761B to make BlueZ fall
back to legacy LE scan commands which the firmware supports correctly.

Tested with RTL8761BU (USB ID 0bda:a728) where the issue manifested
as continuous 'Opcode 0x2042 failed: -16' errors in dmesg whenever
a BLE connection was active.

Signed-off-by: Alexej Sidorenko <alexej@sidorenko.cz>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

diff --git a/drivers/bluetooth/btrtl.c b/drivers/bluetooth/btrtl.c
index 62f9d4df3a4f88eaf58fb96d040ac3a672ab8dfd..49ecb18fea45f4152e0d755bf03cf7ed11b075dc 100644 (file)
--- a/drivers/bluetooth/btrtl.c
+++ b/drivers/bluetooth/btrtl.c
@@ -1342,6 +1342,19 @@ void btrtl_set_quirks(struct hci_dev *hdev, struct btrtl_device_info *btrtl_dev)
        if (!btrtl_dev->ic_info)
                return;
 
+       switch (btrtl_dev->project_id) {
+       case CHIP_ID_8761B:
+               /* RTL8761B/BU reports HCI version 5.1 but does not support
+                * the LE Extended Scan commands (Opcode 0x2042), causing
+                * repeated -EBUSY failures when BlueZ attempts extended
+                * scanning while a connection is active.
+                */
+               hci_set_quirk(hdev, HCI_QUIRK_BROKEN_EXT_SCAN);
+               break;
+       default:
+               break;
+       }
+
        switch (btrtl_dev->ic_info->lmp_subver) {
        case RTL_ROM_LMP_8703B:
                /* 8723CS reports two pages for local ext features,