diff --git a/hw/adc/aspeed_adc.c b/hw/adc/aspeed_adc.c
index 3e820cae1e..5f2b8566f5 100644
--- a/hw/adc/aspeed_adc.c
+++ b/hw/adc/aspeed_adc.c
@@ -228,7 +228,8 @@ static void aspeed_adc_engine_write(void *opaque, hwaddr addr, uint64_t value,
         qemu_log_mask(LOG_UNIMP, "%s: engine[%u]: "
                       "0x%" HWADDR_PRIx " 0x%" PRIx64 "\n",
                       __func__, s->engine_id, addr, value);
-        break;
+        /* Do not update the regs[] array */
+        return;
     }
 
     s->regs[reg] = value;