Upstream linux commit 69fc01296c9281
commit a1286a1fc416 ("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.
Reported-by: Marcin Gołaś marcingol30@gmail.com Signed-off-by: Michael Trimarchi michael@amarulasolutions.com --- drivers/mtd/nand/raw/nand_base.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c index 215b9ba84f..bc61ad03eb 100644 --- a/drivers/mtd/nand/raw/nand_base.c +++ b/drivers/mtd/nand/raw/nand_base.c @@ -4171,10 +4171,13 @@ 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); + } }
/*