scsi: ufs: core: Improve static type checking

Introduce an enumeration type for the overall command status to allow the
compiler to perform more static type checking.

Link: https://lore.kernel.org/r/20211020214024.2007615-4-bvanassche@acm.org
Acked-by: Avri Altman <Avri.Altman@wdc.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/ufs/ufshcd.c

@@ -711,7 +711,7 @@ static inline bool ufshcd_is_device_present(struct ufs_hba *hba)
  * This function is used to get the OCS field from UTRD
  * Returns the OCS field in the UTRD
  */
-static inline int ufshcd_get_tr_ocs(struct ufshcd_lrb *lrbp)
+static enum utp_ocs ufshcd_get_tr_ocs(struct ufshcd_lrb *lrbp)
 {
 	return le32_to_cpu(lrbp->utr_descriptor_ptr->header.dword_2) & MASK_OCS;
 }
@@ -5089,7 +5089,7 @@ ufshcd_transfer_rsp_status(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
 {
 	int result = 0;
 	int scsi_status;
-	int ocs;
+	enum utp_ocs ocs;
 
 	/* overall command status of utrd */
 	ocs = ufshcd_get_tr_ocs(lrbp);
@@ -6631,7 +6631,8 @@ static int ufshcd_issue_tm_cmd(struct ufs_hba *hba, int lun_id, int task_id,
 		u8 tm_function, u8 *tm_response)
 {
 	struct utp_task_req_desc treq = { { 0 }, };
-	int ocs_value, err;
+	enum utp_ocs ocs_value;
+	int err;
 
 	/* Configure task request descriptor */
 	treq.header.dword_0 = cpu_to_le32(UTP_REQ_DESC_INT_CMD);
@@ -6809,7 +6810,7 @@ int ufshcd_exec_raw_upiu_cmd(struct ufs_hba *hba,
 	int err;
 	enum dev_cmd_type cmd_type = DEV_CMD_TYPE_QUERY;
 	struct utp_task_req_desc treq = { { 0 }, };
-	int ocs_value;
+	enum utp_ocs ocs_value;
 	u8 tm_f = be32_to_cpu(req_upiu->header.dword_1) >> 16 & MASK_TM_FUNC;
 
 	switch (msgcode) {

drivers/scsi/ufs/ufshci.h

@@ -389,7 +389,7 @@ enum {
 };
 
 /* Overall command status values */
-enum {
+enum utp_ocs {
 	OCS_SUCCESS			= 0x0,
 	OCS_INVALID_CMD_TABLE_ATTR	= 0x1,
 	OCS_INVALID_PRDT_ATTR		= 0x2,
@@ -402,6 +402,9 @@ enum {
 	OCS_INVALID_CRYPTO_CONFIG	= 0x9,
 	OCS_GENERAL_CRYPTO_ERROR	= 0xA,
 	OCS_INVALID_COMMAND_STATUS	= 0x0F,
+};
+
+enum {
 	MASK_OCS			= 0x0F,
 };