diff --git a/drivers/firmware/scmi/mailbox_agent.c b/drivers/firmware/scmi/mailbox_agent.c
index 16a82f55ab7..cda94565de5 100644
--- a/drivers/firmware/scmi/mailbox_agent.c
+++ b/drivers/firmware/scmi/mailbox_agent.c
@@ -101,7 +101,7 @@ static int scmi_mbox_get_channel(struct udevice *dev,
 	struct scmi_mbox_channel *chan;
 	int ret;
 
-	if (!dev_read_prop(protocol, "shmem", NULL)) {
+	if (!dev_has_ofnode(protocol) || !dev_read_prop(protocol, "shmem", NULL)) {
 		/* Uses agent base channel */
 		*channel = container_of(base_chan, struct scmi_channel, ref);
 
diff --git a/drivers/firmware/scmi/optee_agent.c b/drivers/firmware/scmi/optee_agent.c
index 631625d715b..7170bd1e682 100644
--- a/drivers/firmware/scmi/optee_agent.c
+++ b/drivers/firmware/scmi/optee_agent.c
@@ -331,7 +331,8 @@ static int scmi_optee_get_channel(struct udevice *dev,
 	u32 channel_id;
 	int ret;
 
-	if (dev_read_u32(protocol, "linaro,optee-channel-id", &channel_id)) {
+	if (!dev_has_ofnode(protocol) ||
+	    dev_read_u32(protocol, "linaro,optee-channel-id", &channel_id)) {
 		/* Uses agent base channel */
 		*channel = container_of(base_chan, struct scmi_channel, ref);