Bluetooth: hci_qca: Skip serdev wait when no transfer is pending

qca_suspend() calls serdev_device_wait_until_sent() regardless of
whether a transfer is pending. While it does no active harm since
the function should return immediately it makes the code more
confusing. Add a flag to track whether a transfer is pending and
only call serdev_device_wait_until_sent() is needed.
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

drivers/bluetooth/hci_qca.c

@@ -2048,6 +2048,7 @@ static int __maybe_unused qca_suspend(struct device *dev)
 	struct hci_uart *hu = &qcadev->serdev_hu;
 	struct qca_data *qca = hu->priv;
 	unsigned long flags;
+	bool tx_pending = false;
 	int ret = 0;
 	u8 cmd;
 
@@ -2081,6 +2082,7 @@ static int __maybe_unused qca_suspend(struct device *dev)
 
 		qca->tx_ibs_state = HCI_IBS_TX_ASLEEP;
 		qca->ibs_sent_slps++;
+		tx_pending = true;
 		break;
 
 	case HCI_IBS_TX_ASLEEP:
@@ -2097,8 +2099,10 @@ static int __maybe_unused qca_suspend(struct device *dev)
 	if (ret < 0)
 		goto error;
 
-	serdev_device_wait_until_sent(hu->serdev,
-				      msecs_to_jiffies(CMD_TRANS_TIMEOUT_MS));
+	if (tx_pending) {
+		serdev_device_wait_until_sent(hu->serdev,
+					      msecs_to_jiffies(CMD_TRANS_TIMEOUT_MS));
+	}
 
 	/* Wait for HCI_IBS_SLEEP_IND sent by device to indicate its Tx is going
 	 * to sleep, so that the packet does not wake the system later.