mmc: dw_mmc: Extract setting the DMA descriptor into a separate routine

Make dwmci_prepare_data() function easier to read by extracting the
preparation of IDMAC descriptor into a dedicated function.

No functional change.

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
diff --git a/drivers/mmc/dw_mmc.c b/drivers/mmc/dw_mmc.c
index 8fc2639..d73d58b 100644
--- a/drivers/mmc/dw_mmc.c
+++ b/drivers/mmc/dw_mmc.c
@@ -53,46 +53,57 @@
 	desc->next_addr = (ulong)desc + sizeof(struct dwmci_idmac);
 }
 
-static void dwmci_prepare_data(struct dwmci_host *host,
-			       struct mmc_data *data,
+static void dwmci_prepare_desc(struct mmc_data *data,
 			       struct dwmci_idmac *cur_idmac,
 			       void *bounce_buffer)
 {
-	unsigned long ctrl;
-	unsigned int i = 0, flags, cnt, blk_cnt;
+	struct dwmci_idmac *desc = cur_idmac;
 	ulong data_start, data_end;
+	unsigned int blk_cnt, i;
 
+	data_start = (ulong)cur_idmac;
 	blk_cnt = data->blocks;
 
-	dwmci_wait_reset(host, DWMCI_CTRL_FIFO_RESET);
+	for (i = 0;; i++) {
+		unsigned int flags, cnt;
 
-	/* Clear IDMAC interrupt */
-	dwmci_writel(host, DWMCI_IDSTS, 0xFFFFFFFF);
-
-	data_start = (ulong)cur_idmac;
-	dwmci_writel(host, DWMCI_DBADDR, (ulong)cur_idmac);
-
-	do {
-		flags = DWMCI_IDMAC_OWN | DWMCI_IDMAC_CH ;
-		flags |= (i == 0) ? DWMCI_IDMAC_FS : 0;
+		flags = DWMCI_IDMAC_OWN | DWMCI_IDMAC_CH;
+		if (i == 0)
+			flags |= DWMCI_IDMAC_FS;
 		if (blk_cnt <= 8) {
 			flags |= DWMCI_IDMAC_LD;
 			cnt = data->blocksize * blk_cnt;
 		} else
 			cnt = data->blocksize * 8;
 
-		dwmci_set_idma_desc(cur_idmac, flags, cnt,
-				    (ulong)bounce_buffer + (i * PAGE_SIZE));
+		dwmci_set_idma_desc(desc, flags, cnt,
+				    (ulong)bounce_buffer + i * PAGE_SIZE);
+		desc++;
 
-		cur_idmac++;
 		if (blk_cnt <= 8)
 			break;
 		blk_cnt -= 8;
-		i++;
-	} while(1);
+	}
 
-	data_end = (ulong)cur_idmac;
+	data_end = (ulong)desc;
 	flush_dcache_range(data_start, roundup(data_end, ARCH_DMA_MINALIGN));
+}
+
+static void dwmci_prepare_data(struct dwmci_host *host,
+			       struct mmc_data *data,
+			       struct dwmci_idmac *cur_idmac,
+			       void *bounce_buffer)
+{
+	unsigned long ctrl;
+
+	dwmci_wait_reset(host, DWMCI_CTRL_FIFO_RESET);
+
+	/* Clear IDMAC interrupt */
+	dwmci_writel(host, DWMCI_IDSTS, 0xFFFFFFFF);
+
+	dwmci_writel(host, DWMCI_DBADDR, (ulong)cur_idmac);
+
+	dwmci_prepare_desc(data, cur_idmac, bounce_buffer);
 
 	ctrl = dwmci_readl(host, DWMCI_CTRL);
 	ctrl |= DWMCI_IDMAC_EN | DWMCI_DMA_EN;