From patchwork Sat May 30 17:41:37 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [MTD, NAND] S3C2410: Deal with unaligned lengths in S3C2440 buffer read/write Date: Sat, 30 May 2009 07:41:37 -0000 From: Ben Dooks X-Patchwork-Id: 27880 Message-Id: <1243705298-21814-11-git-send-email-ben-linux@fluff.org> To: linux-mtd@lists.infradead.org Cc: Ben Dooks Add code to deal with fractional lengths, as reported by Werner Almesberger. Re-work of his original patch. Signed-off-by: Ben Dooks --- drivers/mtd/nand/s3c2410.c | 22 ++++++++++++++++++++-- 1 files changed, 20 insertions(+), 2 deletions(-) diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c index d315b51..8a7f960 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 */