From: Lothar Waßmann Date: Tue, 29 Aug 2017 10:17:12 +0000 (+0200) Subject: mtd: nand: make Samsung SLC NAND usable again X-Git-Tag: v4.12.13~23 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2b8b46b24217125e3037b9486a956cf02c8db97a;p=thirdparty%2Fkernel%2Fstable.git mtd: nand: make Samsung SLC NAND usable again commit 69fc01296c92814b62dbfba1600fe7ed2ed304f5 upstream. commit c51d0ac59f24 ("mtd: nand: Move Samsung specific init/detection logic in nand_samsung.c") introduced a regression for Samsung SLC NAND chips. Prior to this commit chip->bits_per_cell was initialized by calling nand_get_bits_per_cell() before using nand_is_slc(). With the offending commit this call is skipped, leaving chip->bits_per_cell cleared to zero when the manufacturer specific '.detect' function calls nand_is_slc() which in turn interprets bits_per_cell != 1 as indication for an MLC chip. The effect is that e.g. a K9F1G08U0F NAND chip is falsely detected as MLC NAND with 4KiB page size rather than SLC with 2KiB page size. Add a call to nand_get_bits_per_cell() before calling the .detect hook function in nand_manufacturer_detect(), so that the nand_is_slc() calls in the manufacturer specific code will return correct results. Fixes: c51d0ac59f24 ("mtd: nand: Move Samsung specific init/detection logic in nand_samsung.c") Signed-off-by: Lothar Waßmann Signed-off-by: Boris Brezillon Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index 6f9771e824766..2be78d1bc195e 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -3972,10 +3972,13 @@ static void nand_manufacturer_detect(struct nand_chip *chip) * nand_decode_ext_id() otherwise. */ if (chip->manufacturer.desc && chip->manufacturer.desc->ops && - chip->manufacturer.desc->ops->detect) + chip->manufacturer.desc->ops->detect) { + /* The 3rd id byte holds MLC / multichip data */ + chip->bits_per_cell = nand_get_bits_per_cell(chip->id.data[2]); chip->manufacturer.desc->ops->detect(chip); - else + } else { nand_decode_ext_id(chip); + } } /*