--- a/cybt_shared_bus_driver.c
+++ b/cybt_shared_bus_driver.c
@@ -501,8 +501,11 @@
 cybt_result_t cybt_get_bt_buf_index(cybt_fw_membuf_index_t *p_buf_index) {
     uint32_t buf[4];
 
-    cybt_mem_read(H2B_BUF_IN_ADDR, (uint8_t *) buf, sizeof(buf));
+    cybt_result_t result = cybt_mem_read(H2B_BUF_IN_ADDR, (uint8_t *) buf, sizeof(buf));
+    if (result != CYBT_SUCCESS) {
+        return result;
+    }
 
     p_buf_index->host2bt_in_val = buf[0];
     p_buf_index->host2bt_out_val = buf[1];
     p_buf_index->bt2host_in_val = buf[2];
@@ -596,7 +599,10 @@
         if ((mem_addr & 0xFFF) + transfer_size > 0x1000) {
             transfer_size = 0x1000 - (mem_addr & 0xFFF);
         }
-        cyw43_ll_read_backplane_mem(cyw43_ll, mem_addr, transfer_size, p_data);
+        int result = cyw43_ll_read_backplane_mem(cyw43_ll, mem_addr, transfer_size, p_data);
+        if (result != 0) {
+            return CYBT_ERR_HCI_READ_FAILED;
+        }
         cybt_debug("  read_mem addr 0x%08lx len %ld\n", mem_addr, transfer_size);
         DUMP_BYTES(p_data, transfer_size);
         data_len -= transfer_size;