From 40ddbf5069bd4e11447c0088fc75318e0aac53f0 Mon Sep 17 00:00:00 2001 From: Roger Quadros Date: Mon, 25 Aug 2014 16:15:33 -0700 Subject: [PATCH] mtd: nand: omap: Fix 1-bit Hamming code scheme, omap_calculate_ecc() commit 65b97cf6b8de introduced in v3.7 caused a regression by using a reversed CS_MASK thus causing omap_calculate_ecc to always fail. As the NAND base driver never checks for .calculate()'s return value, the zeroed ECC values are used as is without showing any error to the user. However, this won't work and the NAND device won't be guarded by any error code. Fix the issue by using the correct mask. Code was tested on omap3beagle using the following procedure - flash the primary bootloader (MLO) from the kernel to the first NAND partition using nandwrite. - boot the board from NAND. This utilizes OMAP ROM loader that relies on 1-bit Hamming code ECC. Fixes: 65b97cf6b8de (mtd: nand: omap2: handle nand on gpmc) Cc: [3.7+] Signed-off-by: Roger Quadros Signed-off-by: Tony Lindgren --- drivers/mtd/nand/omap2.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c index 4dd6178..5967b38 100644 --- a/drivers/mtd/nand/omap2.c +++ b/drivers/mtd/nand/omap2.c @@ -931,7 +931,7 @@ static int omap_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u32 val; val = readl(info->reg.gpmc_ecc_config); - if (((val >> ECC_CONFIG_CS_SHIFT) & ~CS_MASK) != info->gpmc_cs) + if (((val >> ECC_CONFIG_CS_SHIFT) & CS_MASK) != info->gpmc_cs) return -EINVAL; /* read ecc result */ -- 2.7.4