diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index fe2384b019ec..9cfc65ca173d 100644
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -240,6 +240,12 @@ static int tb_switch_nvm_read(void *priv, unsigned int offset, void *val,
 	return dma_port_flash_read(sw->dma_port, offset, val, bytes);
 }
 
+static int tb_switch_nvm_no_read(void *priv, unsigned int offset, void *val,
+				 size_t bytes)
+{
+	return -EPERM;
+}
+
 static int tb_switch_nvm_write(void *priv, unsigned int offset, void *val,
 			       size_t bytes)
 {
@@ -285,6 +291,7 @@ static struct nvmem_device *register_nvmem(struct tb_switch *sw, int id,
 		config.read_only = true;
 	} else {
 		config.name = "nvm_non_active";
+		config.reg_read = tb_switch_nvm_no_read;
 		config.reg_write = tb_switch_nvm_write;
 		config.root_only = true;
 	}