FAILED: patch "[PATCH] Bluetooth: btusb: drop BROKEN_EXT_SCAN quirk for 0bda:a728" failed to apply to 6.18-stable tree

The patch below does not apply to the 6.18-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.18.y
git checkout FETCH_HEAD
git cherry-pick -x df5e35f1663abc2702cf9f9e7eba024129ac5df1
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '[email protected]' --subject-prefix 'PATCH 6.18.y' 'HEAD^..'

Thanks,
Sasha

------------------ original commit in Linus's tree ------------------

From df5e35f1663abc2702cf9f9e7eba024129ac5df1 Mon Sep 17 00:00:00 2001
From: Junjie Cao <[email protected]>
Date: Sun, 20 Sep 2026 10:02:27 +0800
Subject: [PATCH] Bluetooth: btusb: drop BROKEN_EXT_SCAN quirk for 0bda:a728

Commit 5ead2063611a ("Bluetooth: btrtl: fix RTL8761B/BU broken LE extended scan") set HCI_QUIRK_BROKEN_EXT_SCAN on every RTL8761B, and commit ca0583c24661 ("Bluetooth: btusb: limit RTL8761B BROKEN_EXT_SCAN quirk to 0bda:a728") kept it on 0bda:a728 on the assumption that the USB id separates dongles with broken extended scan from those with a broken legacy scan path. It does not. An 0bda:a728 unit (RTL8761BUV, fw 0xdfc6d922) on 6.18.51 fails the same way the UB500 and 0bda:8771
did: LE Set Scan Enable (0x200c) times out with -110 and btusb resets the device. With the flag removed from the table entry, scanning works on that unit.

Two dongles with the same USB id need opposite settings, so the device table cannot key the quirk either. The costs are not symmetric. Without the quirk, the unit it was written for gets -EBUSY on LE Set Extended Scan Enable (0x2042) while a connection is up. With it, 0x200c times out and btusb resets the device on three reported units, two of them in a re-enumeration loop.

Remove the flag and the table entry. 0bda:a728 matches the generic Realtek entry again and runs without the quirk, as before v7.2.

---
 drivers/bluetooth/btusb_main.c | 8 --------
 1 file changed, 8 deletions(-)

index cccdfb0461fee..3518f92ebbd3d 100644
@@ -70,7 +70,6 @@ static struct usb_driver btusb_driver;
 #define BTUSB_INTEL_NO_WBS_SUPPORT	BIT(26)
 #define BTUSB_ACTIONS_SEMI		BIT(27)
 #define BTUSB_BARROT			BIT(28)
-#define BTUSB_BROKEN_EXT_SCAN		BIT(29)
 #define BTUSB_QUALCOMM			BIT(30)
 
 static const struct usb_device_id btusb_table[] = {

@@ -650,10 +649,6 @@ static const struct usb_device_id quirks_table[] = {
 	{ USB_DEVICE(0x0489, 0xe130), .driver_info = BTUSB_REALTEK |
 						     BTUSB_WIDEBAND_SPEECH },
 
-	/* Realtek 8761BU Bluetooth devices */
-	{ USB_DEVICE(0x0bda, 0xa728), .driver_info = BTUSB_REALTEK |
-						     BTUSB_BROKEN_EXT_SCAN },
-
 	/* Realtek Bluetooth devices */
 	{ USB_VENDOR_AND_INTERFACE_INFO(0x0bda, 0xe0, 0x01, 0x01),
 	  .driver_info = BTUSB_REALTEK },

@@ -4754,9 +4749,6 @@ static int btusb_probe(struct usb_interface *intf,
 	if (id->driver_info & BTUSB_INVALID_LE_STATES)
 		hci_set_quirk(hdev, HCI_QUIRK_BROKEN_LE_STATES);
 
-	if (id->driver_info & BTUSB_BROKEN_EXT_SCAN)
-		hci_set_quirk(hdev, HCI_QUIRK_BROKEN_EXT_SCAN);
-
 	if (id->driver_info & BTUSB_DIGIANSWER) {
 		data->cmdreq_type = USB_TYPE_VENDOR;
 		hci_set_quirk(hdev, HCI_QUIRK_RESET_ON_CLOSE);

2.53.0

From: Junjie Cao <[email protected]>

[ Upstream commit df5e35f1663abc2702cf9f9e7eba024129ac5df1 ]

Commit 5ead2063611a ("Bluetooth: btrtl: fix RTL8761B/BU broken LE extended scan") set HCI_QUIRK_BROKEN_EXT_SCAN on every RTL8761B, and commit ca0583c24661 ("Bluetooth: btusb: limit RTL8761B BROKEN_EXT_SCAN quirk to 0bda:a728") kept it on 0bda:a728 on the assumption that the USB id separates dongles with broken extended scan from those with a broken legacy scan path. It does not. An 0bda:a728 unit (RTL8761BUV, fw 0xdfc6d922) on 6.18.51 fails the same way the UB500 and 0bda:8771
did: LE Set Scan Enable (0x200c) times out with -110 and btusb resets the device. With the flag removed from the table entry, scanning works on that unit.

Two dongles with the same USB id need opposite settings, so the device table cannot key the quirk either. The costs are not symmetric. Without the quirk, the unit it was written for gets -EBUSY on LE Set Extended Scan Enable (0x2042) while a connection is up. With it, 0x200c times out and btusb resets the device on three reported units, two of them in a re-enumeration loop.

Remove the flag and the table entry. 0bda:a728 matches the generic Realtek entry again and runs without the quirk, as before v7.2.

---
 drivers/bluetooth/btusb.c | 8 --------
 1 file changed, 8 deletions(-)

index b6773ef24c438..6143414711c5d 100644
@@ -67,7 +67,6 @@ static struct usb_driver btusb_driver;
 #define BTUSB_INTEL_NO_WBS_SUPPORT	BIT(26)
 #define BTUSB_ACTIONS_SEMI		BIT(27)
 #define BTUSB_BARROT			BIT(28)
-#define BTUSB_BROKEN_EXT_SCAN		BIT(29)
 
 static const struct usb_device_id btusb_table[] = {
 	/*

@@ -633,10 +632,6 @@ static const struct usb_device_id quirks_table[] = {
 	{ USB_DEVICE(0x0489, 0xe130), .driver_info = BTUSB_REALTEK |
 						     BTUSB_WIDEBAND_SPEECH },
 
-	/* Realtek 8761BU Bluetooth devices */
-	{ USB_DEVICE(0x0bda, 0xa728), .driver_info = BTUSB_REALTEK |
-						     BTUSB_BROKEN_EXT_SCAN },
-
 	/* Realtek Bluetooth devices */
 	{ USB_VENDOR_AND_INTERFACE_INFO(0x0bda, 0xe0, 0x01, 0x01),
 	  .driver_info = BTUSB_REALTEK },

@@ -4356,9 +4351,6 @@ static int btusb_probe(struct usb_interface *intf,
 	if (id->driver_info & BTUSB_INVALID_LE_STATES)
 		hci_set_quirk(hdev, HCI_QUIRK_BROKEN_LE_STATES);
 
-	if (id->driver_info & BTUSB_BROKEN_EXT_SCAN)
-		hci_set_quirk(hdev, HCI_QUIRK_BROKEN_EXT_SCAN);
-
 	if (id->driver_info & BTUSB_DIGIANSWER) {
 		data->cmdreq_type = USB_TYPE_VENDOR;
 		hci_set_quirk(hdev, HCI_QUIRK_RESET_ON_CLOSE);

2.53.0