Patch "Bluetooth: btusb: mediatek: fix WMT failure during runtime suspend" has been added to the 5.10-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    Bluetooth: btusb: mediatek: fix WMT failure during runtime suspend

to the 5.10-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     bluetooth-btusb-mediatek-fix-wmt-failure-during-runt.patch
and it can be found in the queue-5.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit fc0452655082897551f10199aad7266e5328d4f6
Author: Sean Wang <sean.wang@xxxxxxxxxxxx>
Date:   Thu Aug 11 08:49:07 2022 +0800

    Bluetooth: btusb: mediatek: fix WMT failure during runtime suspend
    
    [ Upstream commit fd3f106677bac70437dc12e76c827294ed495a44 ]
    
    WMT cmd/event doesn't follow up the generic HCI cmd/event handling, it
    needs constantly polling control pipe until the host received the WMT
    event, thus, we should require to specifically acquire PM counter on the
    USB to prevent the interface from entering auto suspended while WMT
    cmd/event in progress.
    
    Fixes: a1c49c434e15 ("Bluetooth: btusb: Add protocol support for MediaTek MT7668U USB devices")
    Co-developed-by: Jing Cai <jing.cai@xxxxxxxxxxxx>
    Signed-off-by: Jing Cai <jing.cai@xxxxxxxxxxxx>
    Signed-off-by: Sean Wang <sean.wang@xxxxxxxxxxxx>
    Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 80a3d5019950..6efd981979bd 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -3033,15 +3033,29 @@ static int btusb_mtk_hci_wmt_sync(struct hci_dev *hdev,
 
 	set_bit(BTUSB_TX_WAIT_VND_EVT, &data->flags);
 
+	/* WMT cmd/event doesn't follow up the generic HCI cmd/event handling,
+	 * it needs constantly polling control pipe until the host received the
+	 * WMT event, thus, we should require to specifically acquire PM counter
+	 * on the USB to prevent the interface from entering auto suspended
+	 * while WMT cmd/event in progress.
+	 */
+	err = usb_autopm_get_interface(data->intf);
+	if (err < 0)
+		goto err_free_wc;
+
 	err = __hci_cmd_send(hdev, 0xfc6f, hlen, wc);
 
 	if (err < 0) {
 		clear_bit(BTUSB_TX_WAIT_VND_EVT, &data->flags);
+		usb_autopm_put_interface(data->intf);
 		goto err_free_wc;
 	}
 
 	/* Submit control IN URB on demand to process the WMT event */
 	err = btusb_mtk_submit_wmt_recv_urb(hdev);
+
+	usb_autopm_put_interface(data->intf);
+
 	if (err < 0)
 		return err;