diff --git a/include/spdk/nvme_spec.h b/include/spdk/nvme_spec.h
index 1067b0848..2c5df546f 100644
--- a/include/spdk/nvme_spec.h
+++ b/include/spdk/nvme_spec.h
@@ -242,7 +242,7 @@ struct spdk_nvme_registers {
 	union spdk_nvme_cc_register	cc;
 
 	uint32_t	reserved1;
-	uint32_t	csts;		/* controller status */
+	union spdk_nvme_csts_register	csts;		/* controller status */
 	uint32_t	nssr;		/* NVM subsystem reset */
 
 	/** admin queue attributes */
diff --git a/lib/nvme/nvme_ctrlr.c b/lib/nvme/nvme_ctrlr.c
index a520ec6c3..9247b3083 100644
--- a/lib/nvme/nvme_ctrlr.c
+++ b/lib/nvme/nvme_ctrlr.c
@@ -258,7 +258,7 @@ nvme_ctrlr_wait_for_ready(struct spdk_nvme_ctrlr *ctrlr, int desired_ready_value
 	cap_lo.raw = nvme_mmio_read_4(ctrlr, cap_lo.raw);
 	ready_timeout_in_ms = cap_lo.bits.to * 500;
 
-	csts.raw = nvme_mmio_read_4(ctrlr, csts);
+	csts.raw = nvme_mmio_read_4(ctrlr, csts.raw);
 
 	ms_waited = 0;
 
@@ -269,7 +269,7 @@ nvme_ctrlr_wait_for_ready(struct spdk_nvme_ctrlr *ctrlr, int desired_ready_value
 				    "within %d ms\n", desired_ready_value, ready_timeout_in_ms);
 			return ENXIO;
 		}
-		csts.raw = nvme_mmio_read_4(ctrlr, csts);
+		csts.raw = nvme_mmio_read_4(ctrlr, csts.raw);
 	}
 
 	return 0;
@@ -282,7 +282,7 @@ nvme_ctrlr_disable(struct spdk_nvme_ctrlr *ctrlr)
 	union spdk_nvme_csts_register csts;
 
 	cc.raw = nvme_mmio_read_4(ctrlr, cc.raw);
-	csts.raw = nvme_mmio_read_4(ctrlr, csts);
+	csts.raw = nvme_mmio_read_4(ctrlr, csts.raw);
 
 	if (cc.bits.en == 1 && csts.bits.rdy == 0) {
 		nvme_ctrlr_wait_for_ready(ctrlr, 1);
@@ -305,7 +305,7 @@ nvme_ctrlr_shutdown(struct spdk_nvme_ctrlr *ctrlr)
 	cc.bits.shn = SPDK_NVME_SHN_NORMAL;
 	nvme_mmio_write_4(ctrlr, cc.raw, cc.raw);
 
-	csts.raw = nvme_mmio_read_4(ctrlr, csts);
+	csts.raw = nvme_mmio_read_4(ctrlr, csts.raw);
 	/*
 	 * The NVMe spec does not define a timeout period
 	 *  for shutdown notification, so we just pick
@@ -314,7 +314,7 @@ nvme_ctrlr_shutdown(struct spdk_nvme_ctrlr *ctrlr)
 	 */
 	while (csts.bits.shst != SPDK_NVME_SHST_COMPLETE) {
 		nvme_delay(1000);
-		csts.raw = nvme_mmio_read_4(ctrlr, csts);
+		csts.raw = nvme_mmio_read_4(ctrlr, csts.raw);
 		if (ms_waited++ >= 5000)
 			break;
 	}
@@ -728,7 +728,7 @@ nvme_ctrlr_process_init(struct spdk_nvme_ctrlr *ctrlr)
 	int rc;
 
 	cc.raw = nvme_mmio_read_4(ctrlr, cc.raw);
-	csts.raw = nvme_mmio_read_4(ctrlr, csts);
+	csts.raw = nvme_mmio_read_4(ctrlr, csts.raw);
 	cap_lo.raw = nvme_mmio_read_4(ctrlr, cap_lo.raw);
 
 	ready_timeout_in_ms = 500 * cap_lo.bits.to;