From: Ben Dooks <ben-linux@fluff.org>
Date: Sat, 30 May 2009 17:30:18 +0000 (+0100)
Subject: [MTD] [NAND] S3C2410: Deal with unaligned lengths in S3C2440 buffer read/write
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=dea2aa6fd7d46c43c840ad77905f3c161d5bc59d;p=linux-beck.git

[MTD] [NAND] S3C2410: Deal with unaligned lengths in S3C2440 buffer read/write

Add code to deal with fractional lengths, as reported by
Werner Almesberger. Re-work of his original patch.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
---

diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c
index d315b513db5c..8a7f960a0df5 100644
--- a/drivers/mtd/nand/s3c2410.c
+++ b/drivers/mtd/nand/s3c2410.c
@@ -584,7 +584,16 @@ static void s3c2410_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
 static void s3c2440_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
 {
 	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
-	readsl(info->regs + S3C2440_NFDATA, buf, len / 4);
+
+	readsl(info->regs + S3C2440_NFDATA, buf, len >> 2);
+
+	/* cleanup if we've got less than a word to do */
+	if (len & 3) {
+		buf += len & ~3;
+
+		for (; len & 3; len--)
+			*buf++ = readb(info->regs + S3C2440_NFDATA);
+	}
 }
 
 static void s3c2410_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
@@ -596,7 +605,16 @@ static void s3c2410_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int
 static void s3c2440_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
 {
 	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
-	writesl(info->regs + S3C2440_NFDATA, buf, len / 4);
+
+	writesl(info->regs + S3C2440_NFDATA, buf, len >> 2);
+
+	/* cleanup any fractional write */
+	if (len & 3) {
+		buf += len & ~3;
+
+		for (; len & 3; len--, buf++)
+			writeb(*buf, info->regs + S3C2440_NFDATA);
+	}
 }
 
 /* cpufreq driver support */