diff --git a/drivers/scsi/libsas/sas_expander.c b/drivers/scsi/libsas/sas_expander.c
index 260e735d06fa4c5259e00dd497e28ff88b62e7d4..fb998a8a7d3b569980b901425bee19712c887764 100644
--- a/drivers/scsi/libsas/sas_expander.c
+++ b/drivers/scsi/libsas/sas_expander.c
@@ -175,13 +175,13 @@ static enum sas_device_type to_dev_type(struct discover_resp *dr)
 		return dr->attached_dev_type;
 }
 
-static void sas_set_ex_phy(struct domain_device *dev, int phy_id, void *rsp)
+static void sas_set_ex_phy(struct domain_device *dev, int phy_id,
+			   struct smp_disc_resp *disc_resp)
 {
 	enum sas_device_type dev_type;
 	enum sas_linkrate linkrate;
 	u8 sas_addr[SAS_ADDR_SIZE];
-	struct smp_resp *resp = rsp;
-	struct discover_resp *dr = &resp->disc;
+	struct discover_resp *dr = &disc_resp->disc;
 	struct sas_ha_struct *ha = dev->port->ha;
 	struct expander_device *ex = &dev->ex_dev;
 	struct ex_phy *phy = &ex->ex_phy[phy_id];
@@ -198,7 +198,7 @@ static void sas_set_ex_phy(struct domain_device *dev, int phy_id, void *rsp)
 		BUG_ON(!phy->phy);
 	}
 
-	switch (resp->result) {
+	switch (disc_resp->result) {
 	case SMP_RESP_PHY_VACANT:
 		phy->phy_state = PHY_VACANT;
 		break;
@@ -347,12 +347,13 @@ struct domain_device *sas_ex_to_ata(struct domain_device *ex_dev, int phy_id)
 }
 
 #define DISCOVER_REQ_SIZE  16
-#define DISCOVER_RESP_SIZE 56
+#define DISCOVER_RESP_SIZE sizeof(struct smp_disc_resp)
 
 static int sas_ex_phy_discover_helper(struct domain_device *dev, u8 *disc_req,
-				      u8 *disc_resp, int single)
+				      struct smp_disc_resp *disc_resp,
+				      int single)
 {
-	struct discover_resp *dr;
+	struct discover_resp *dr = &disc_resp->disc;
 	int res;
 
 	disc_req[9] = single;
@@ -361,7 +362,6 @@ static int sas_ex_phy_discover_helper(struct domain_device *dev, u8 *disc_req,
 			       disc_resp, DISCOVER_RESP_SIZE);
 	if (res)
 		return res;
-	dr = &((struct smp_resp *)disc_resp)->disc;
 	if (memcmp(dev->sas_addr, dr->attached_sas_addr, SAS_ADDR_SIZE) == 0) {
 		pr_notice("Found loopback topology, just ignore it!\n");
 		return 0;
@@ -375,7 +375,7 @@ int sas_ex_phy_discover(struct domain_device *dev, int single)
 	struct expander_device *ex = &dev->ex_dev;
 	int  res = 0;
 	u8   *disc_req;
-	u8   *disc_resp;
+	struct smp_disc_resp *disc_resp;
 
 	disc_req = alloc_smp_req(DISCOVER_REQ_SIZE);
 	if (!disc_req)
@@ -1657,7 +1657,7 @@ int sas_discover_root_expander(struct domain_device *dev)
 /* ---------- Domain revalidation ---------- */
 
 static int sas_get_phy_discover(struct domain_device *dev,
-				int phy_id, struct smp_resp *disc_resp)
+				int phy_id, struct smp_disc_resp *disc_resp)
 {
 	int res;
 	u8 *disc_req;
@@ -1673,10 +1673,8 @@ static int sas_get_phy_discover(struct domain_device *dev,
 			       disc_resp, DISCOVER_RESP_SIZE);
 	if (res)
 		goto out;
-	else if (disc_resp->result != SMP_RESP_FUNC_ACC) {
+	if (disc_resp->result != SMP_RESP_FUNC_ACC)
 		res = disc_resp->result;
-		goto out;
-	}
 out:
 	kfree(disc_req);
 	return res;
@@ -1686,7 +1684,7 @@ static int sas_get_phy_change_count(struct domain_device *dev,
 				    int phy_id, int *pcc)
 {
 	int res;
-	struct smp_resp *disc_resp;
+	struct smp_disc_resp *disc_resp;
 
 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
 	if (!disc_resp)
@@ -1704,19 +1702,17 @@ static int sas_get_phy_attached_dev(struct domain_device *dev, int phy_id,
 				    u8 *sas_addr, enum sas_device_type *type)
 {
 	int res;
-	struct smp_resp *disc_resp;
-	struct discover_resp *dr;
+	struct smp_disc_resp *disc_resp;
 
 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
 	if (!disc_resp)
 		return -ENOMEM;
-	dr = &disc_resp->disc;
 
 	res = sas_get_phy_discover(dev, phy_id, disc_resp);
 	if (res == 0) {
 		memcpy(sas_addr, disc_resp->disc.attached_sas_addr,
 		       SAS_ADDR_SIZE);
-		*type = to_dev_type(dr);
+		*type = to_dev_type(&disc_resp->disc);
 		if (*type == 0)
 			memset(sas_addr, 0, SAS_ADDR_SIZE);
 	}
diff --git a/include/scsi/sas.h b/include/scsi/sas.h
index acfc69fd72d0487111133e3a1e130ed375e0160c..b3ee9bd632778222413496fa81229b961ae05417 100644
--- a/include/scsi/sas.h
+++ b/include/scsi/sas.h
@@ -471,18 +471,6 @@ struct report_phy_sata_resp {
 	__be32 crc;
 } __attribute__ ((packed));
 
-struct smp_resp {
-	u8    frame_type;
-	u8    function;
-	u8    result;
-	u8    reserved;
-	union {
-		struct report_general_resp  rg;
-		struct discover_resp        disc;
-		struct report_phy_sata_resp rps;
-	};
-} __attribute__ ((packed));
-
 #elif defined(__BIG_ENDIAN_BITFIELD)
 struct sas_identify_frame {
 	/* Byte 0 */
@@ -704,6 +692,18 @@ struct report_phy_sata_resp {
 	__be32 crc;
 } __attribute__ ((packed));
 
+#else
+#error "Bitfield order not defined!"
+#endif
+
+struct smp_disc_resp {
+	u8    frame_type;
+	u8    function;
+	u8    result;
+	u8    reserved;
+	struct discover_resp disc;
+} __attribute__ ((packed));
+
 struct smp_resp {
 	u8    frame_type;
 	u8    function;
@@ -716,8 +716,4 @@ struct smp_resp {
 	};
 } __attribute__ ((packed));
 
-#else
-#error "Bitfield order not defined!"
-#endif
-
 #endif /* _SAS_H_ */