[PATCH v3 5/5] dmaengine: sh: rz-dmac: rz_dmac_prepare_descs_for_slave_sg() improvements

[Biju Das <biju.das.jz@xxxxxxxxxxxxxx>]

Improve rz_dmac_prepare_descs_for_slave_sg() by replacing the loop
for->for_each_sg and drop the variables sgl and sg_len.

Also, assign lmdesc along with the declaration and improve the logic for
assigning lmdesc->chcfg and lmdesc->header.

Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
---
v2->v3:
 * Assign header after chcfg to make sure there is no code flow change.
 * Updated commit description.
v2:
 * New patch.
---
 drivers/dma/sh/rz-dmac.c | 22 +++++++++-------------
 1 file changed, 9 insertions(+), 13 deletions(-)

diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c
index 153893045932..7c75ff314ea3 100644
--- a/drivers/dma/sh/rz-dmac.c
+++ b/drivers/dma/sh/rz-dmac.c
@@ -342,12 +342,12 @@ static void rz_dmac_prepare_desc_for_memcpy(struct rz_dmac_chan *channel)
 
 static void rz_dmac_prepare_descs_for_slave_sg(struct rz_dmac_chan *channel)
 {
+	struct rz_lmdesc *lmdesc = channel->lmdesc.tail;
 	struct dma_chan *chan = &channel->vc.chan;
 	struct rz_dmac *dmac = to_rz_dmac(chan->device);
 	struct rz_dmac_desc *d = channel->desc;
-	struct scatterlist *sg, *sgl = d->sg;
-	struct rz_lmdesc *lmdesc;
-	unsigned int i, sg_len = d->sgcount;
+	struct scatterlist *sg;
+	unsigned int i;
 
 	channel->chcfg |= CHCFG_SEL(channel->index) | CHCFG_DEM | CHCFG_DMS;
 
@@ -358,9 +358,7 @@ static void rz_dmac_prepare_descs_for_slave_sg(struct rz_dmac_chan *channel)
 		channel->chcfg |= CHCFG_DAD | CHCFG_REQD;
 	}
 
-	lmdesc = channel->lmdesc.tail;
-
-	for (i = 0, sg = sgl; i < sg_len; i++, sg = sg_next(sg)) {
+	for_each_sg(d->sg, sg, d->sgcount, i) {
 		if (d->direction == DMA_DEV_TO_MEM) {
 			lmdesc->sa = channel->src_per_address;
 			lmdesc->da = sg_dma_address(sg);
@@ -372,13 +370,11 @@ static void rz_dmac_prepare_descs_for_slave_sg(struct rz_dmac_chan *channel)
 		lmdesc->tb = sg_dma_len(sg);
 		lmdesc->chitvl = 0;
 		lmdesc->chext = 0;
-		if (i == (sg_len - 1)) {
-			lmdesc->chcfg = (channel->chcfg & ~CHCFG_DEM);
-			lmdesc->header = HEADER_LV;
-		} else {
-			lmdesc->chcfg = channel->chcfg;
-			lmdesc->header = HEADER_LV;
-		}
+		lmdesc->chcfg = channel->chcfg;
+		if (i == (d->sgcount - 1))
+			lmdesc->chcfg &= ~CHCFG_DEM;
+
+		lmdesc->header = HEADER_LV;
 		if (++lmdesc >= (channel->lmdesc.base + DMAC_NR_LMDESC))
 			lmdesc = channel->lmdesc.base;
 	}
-- 
2.25.1