linux-kernel - [PATCH v2] memory: renesas-rpc-if: Simplify single/double data register access

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Date:   Wed, 13 Apr 2022 15:49:21 +0200
From:   Geert Uytterhoeven <geert+renesas@...der.be>
To:     Krzysztof Kozlowski <krzk@...nel.org>
Cc:     Wolfram Sang <wsa+renesas@...g-engineering.com>,
        Sergey Shtylyov <s.shtylyov@....ru>,
        Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>,
        Andrew Gabbasov <andrew_gabbasov@...tor.com>,
        linux-renesas-soc@...r.kernel.org, linux-mtd@...ts.infradead.org,
        linux-kernel@...r.kernel.org,
        Geert Uytterhoeven <geert+renesas@...der.be>
Subject: [PATCH v2] memory: renesas-rpc-if: Simplify single/double data register access

For manual write and read, factor out the common access to the first
data register by keeping track of the current data pointer.

Signed-off-by: Geert Uytterhoeven <geert+renesas@...der.be>
Tested-by: Wolfram Sang <wsa+renesas@...g-engineering.com>
Reviewed-by: Wolfram Sang <wsa+renesas@...g-engineering.com>
---
v2:
  - Add Tested-by, Reviewed-by,
  - Remove unneeded pointer post-increments from final dereferences.
---
 drivers/memory/renesas-rpc-if.c | 28 ++++++++--------------------
 1 file changed, 8 insertions(+), 20 deletions(-)

diff --git a/drivers/memory/renesas-rpc-if.c b/drivers/memory/renesas-rpc-if.c
index 019a0822bde0e413..ba9c526833c0f4da 100644
--- a/drivers/memory/renesas-rpc-if.c
+++ b/drivers/memory/renesas-rpc-if.c
@@ -488,7 +488,7 @@ int rpcif_manual_xfer(struct rpcif *rpc)
 	case RPCIF_DATA_OUT:
 		while (pos < rpc->xferlen) {
 			u32 bytes_left = rpc->xferlen - pos;
-			u32 nbytes, data[2];
+			u32 nbytes, data[2], *p = data;
 
 			smcr = rpc->smcr | RPCIF_SMCR_SPIE;
 
@@ -502,15 +502,9 @@ int rpcif_manual_xfer(struct rpcif *rpc)
 			rpc->xfer_size = nbytes;
 
 			memcpy(data, rpc->buffer + pos, nbytes);
-			if (nbytes == 8) {
-				regmap_write(rpc->regmap, RPCIF_SMWDR1,
-					     data[0]);
-				regmap_write(rpc->regmap, RPCIF_SMWDR0,
-					     data[1]);
-			} else {
-				regmap_write(rpc->regmap, RPCIF_SMWDR0,
-					     data[0]);
-			}
+			if (nbytes == 8)
+				regmap_write(rpc->regmap, RPCIF_SMWDR1, *p++);
+			regmap_write(rpc->regmap, RPCIF_SMWDR0, *p);
 
 			regmap_write(rpc->regmap, RPCIF_SMCR, smcr);
 			ret = wait_msg_xfer_end(rpc);
@@ -552,7 +546,7 @@ int rpcif_manual_xfer(struct rpcif *rpc)
 		}
 		while (pos < rpc->xferlen) {
 			u32 bytes_left = rpc->xferlen - pos;
-			u32 nbytes, data[2];
+			u32 nbytes, data[2], *p = data;
 
 			/* nbytes may only be 1, 2, 4, or 8 */
 			nbytes = bytes_left >= max ? max : (1 << ilog2(bytes_left));
@@ -569,15 +563,9 @@ int rpcif_manual_xfer(struct rpcif *rpc)
 			if (ret)
 				goto err_out;
 
-			if (nbytes == 8) {
-				regmap_read(rpc->regmap, RPCIF_SMRDR1,
-					    &data[0]);
-				regmap_read(rpc->regmap, RPCIF_SMRDR0,
-					    &data[1]);
-			} else {
-				regmap_read(rpc->regmap, RPCIF_SMRDR0,
-					    &data[0]);
-			}
+			if (nbytes == 8)
+				regmap_read(rpc->regmap, RPCIF_SMRDR1, p++);
+			regmap_read(rpc->regmap, RPCIF_SMRDR0, p);
 			memcpy(rpc->buffer + pos, data, nbytes);
 
 			pos += nbytes;
-- 
2.25.1