Bluetooth: btmtk: Fix failed to send func ctrl for MediaTek devices.

Use usb_autopm_get_interface() and usb_autopm_put_interface()
in btmtk_usb_shutdown(), it could send func ctrl after enabling
autosuspend.

Bluetooth: btmtk_usb_hci_wmt_sync() hci0: Execution of wmt command
           timed out
Bluetooth: btmtk_usb_shutdown() hci0: Failed to send wmt func ctrl
           (-110)

Fixes: 5c5e8c5 ("Bluetooth: btmtk: move btusb_mtk_[setup, shutdown] to btmtk.c")
Signed-off-by: Chris Lu <[email protected]>
Signed-off-by: Luiz Augusto von Dentz <[email protected]>

Author: ChrisCH-Lu

drivers/bluetooth/btmtk.c

@@ -1472,10 +1472,15 @@ EXPORT_SYMBOL_GPL(btmtk_usb_setup);
 
 int btmtk_usb_shutdown(struct hci_dev *hdev)
 {
+	struct btmtk_data *data = hci_get_priv(hdev);
 	struct btmtk_hci_wmt_params wmt_params;
 	u8 param = 0;
 	int err;
 
+	err = usb_autopm_get_interface(data->intf);
+	if (err < 0)
+		return err;
+
 	/* Disable the device */
 	wmt_params.op = BTMTK_WMT_FUNC_CTRL;
 	wmt_params.flag = 0;
@@ -1486,9 +1491,11 @@ int btmtk_usb_shutdown(struct hci_dev *hdev)
 	err = btmtk_usb_hci_wmt_sync(hdev, &wmt_params);
 	if (err < 0) {
 		bt_dev_err(hdev, "Failed to send wmt func ctrl (%d)", err);
+		usb_autopm_put_interface(data->intf);
 		return err;
 	}
 
+	usb_autopm_put_interface(data->intf);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(btmtk_usb_shutdown);

net/bluetooth/rfcomm/tty.c

@@ -201,14 +201,14 @@ static ssize_t address_show(struct device *tty_dev,
 			    struct device_attribute *attr, char *buf)
 {
 	struct rfcomm_dev *dev = dev_get_drvdata(tty_dev);
-	return sprintf(buf, "%pMR\n", &dev->dst);
+	return sysfs_emit(buf, "%pMR\n", &dev->dst);
 }
 
 static ssize_t channel_show(struct device *tty_dev,
 			    struct device_attribute *attr, char *buf)
 {
 	struct rfcomm_dev *dev = dev_get_drvdata(tty_dev);
-	return sprintf(buf, "%d\n", dev->channel);
+	return sysfs_emit(buf, "%d\n", dev->channel);
 }
 
 static DEVICE_ATTR_RO(address);