From: Masahiro Yamada Date: Thu, 30 Mar 2017 06:45:47 +0000 (+0900) Subject: mtd: nand: relax ecc.read_page() return value for uncorrectable ECC X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=07604686e808cd93d352172806a7828860f048f5;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git mtd: nand: relax ecc.read_page() return value for uncorrectable ECC The comment for ecc.read_page() requires that it should return "0 if bitflips uncorrectable". Actually, drivers could return positive values when uncorrectable bitflips occur. For example, nand_read_page_swecc() is the case. If ecc.correct() returns -EBADMSG for the first ECC sector, and a positive value for the second one, nand_read_page_swecc() returns a positive max_bitflips and increments ecc_stats.failed for the same page. The requirement can be relaxed by tweaking nand_do_read_ops(). Move the max_bitflips calculation below the retry. Signed-off-by: Masahiro Yamada Suggested-by: Boris Brezillon Signed-off-by: Boris Brezillon --- diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index 36258e69a389..de6c8045c85b 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -1993,8 +1993,6 @@ read_retry: break; } - max_bitflips = max_t(unsigned int, max_bitflips, ret); - /* Transfer not aligned data */ if (use_bufpoi) { if (!NAND_HAS_SUBPAGE_READ(chip) && !oob && @@ -2045,6 +2043,7 @@ read_retry: } buf += bytes; + max_bitflips = max_t(unsigned int, max_bitflips, ret); } else { memcpy(buf, chip->buffers->databuf + col, bytes); buf += bytes; diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h index 40657939797c..9e0c93c44bef 100644 --- a/include/linux/mtd/nand.h +++ b/include/linux/mtd/nand.h @@ -516,7 +516,7 @@ static inline void nand_hw_control_init(struct nand_hw_control *nfc) * out-of-band data). * @read_page: function to read a page according to the ECC generator * requirements; returns maximum number of bitflips corrected in - * any single ECC step, 0 if bitflips uncorrectable, -EIO hw error + * any single ECC step, -EIO hw error * @read_subpage: function to read parts of the page covered by ECC; * returns same as read_page() * @write_subpage: function to write parts of the page covered by ECC.