mmc: cqhci: introduce get_trans_desc_offset()

The same calculation to get transfer descriptor offset is already used
at 3 different locations. Let's create a new helper to simplify code.
Signed-off-by: Yue Hu <huyue2@yulong.com>
Link: https://lore.kernel.org/r/20210521034432.2321-1-zbestahu@gmail.comSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/cqhci-core.c

@@ -45,17 +45,23 @@ static inline u8 *get_link_desc(struct cqhci_host *cq_host, u8 tag)
 	return desc + cq_host->task_desc_len;
 }
 
+static inline size_t get_trans_desc_offset(struct cqhci_host *cq_host, u8 tag)
+{
+	return cq_host->trans_desc_len * cq_host->mmc->max_segs * tag;
+}
+
 static inline dma_addr_t get_trans_desc_dma(struct cqhci_host *cq_host, u8 tag)
 {
-	return cq_host->trans_desc_dma_base +
-		(cq_host->mmc->max_segs * tag *
-		 cq_host->trans_desc_len);
+	size_t offset = get_trans_desc_offset(cq_host, tag);
+
+	return cq_host->trans_desc_dma_base + offset;
 }
 
 static inline u8 *get_trans_desc(struct cqhci_host *cq_host, u8 tag)
 {
-	return cq_host->trans_desc_base +
-		(cq_host->trans_desc_len * cq_host->mmc->max_segs * tag);
+	size_t offset = get_trans_desc_offset(cq_host, tag);
+
+	return cq_host->trans_desc_base + offset;
 }
 
 static void setup_trans_desc(struct cqhci_host *cq_host, u8 tag)
@@ -194,8 +200,7 @@ static int cqhci_host_alloc_tdl(struct cqhci_host *cq_host)
 
 	cq_host->desc_size = cq_host->slot_sz * cq_host->num_slots;
 
-	cq_host->data_size = cq_host->trans_desc_len * cq_host->mmc->max_segs *
-		cq_host->mmc->cqe_qdepth;
+	cq_host->data_size = get_trans_desc_offset(cq_host, cq_host->mmc->cqe_qdepth);
 
 	pr_debug("%s: cqhci: desc_size: %zu data_sz: %zu slot-sz: %d\n",
 		 mmc_hostname(cq_host->mmc), cq_host->desc_size, cq_host->data_size,