diff --git a/drivers/firmware/arm_scmi/transports/mailbox.c b/drivers/firmware/arm_scmi/transports/mailbox.c
index b6459fbb8151..37e3eab529ea 100644
--- a/drivers/firmware/arm_scmi/transports/mailbox.c
+++ b/drivers/firmware/arm_scmi/transports/mailbox.c
@@ -230,9 +230,10 @@ static int mailbox_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
 		smbox->chan_receiver = mbox_request_channel(cl, a2p_rx_chan);
 		if (IS_ERR(smbox->chan_receiver)) {
 			ret = PTR_ERR(smbox->chan_receiver);
+			smbox->chan_receiver = NULL;
 			if (ret != -EPROBE_DEFER)
 				dev_err(cdev, "failed to request SCMI Tx Receiver mailbox\n");
-			return ret;
+			goto err_free_chan;
 		}
 	}
 
@@ -248,6 +249,8 @@ static int mailbox_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
 
 	return 0;
 
+err_free_chan:
+	mbox_free_channel(smbox->chan);
 err_clear_cinfo:
 	cinfo->transport_info = NULL;
 	smbox->cinfo = NULL;