From f23a481c4e0ccb006470b1c890cc7236ba634e67 Mon Sep 17 00:00:00 2001 From: Brian Norris Date: Mon, 24 Sep 2012 20:40:51 -0700 Subject: mtd: nand: split simple ID decode into its own function When detecting NAND parameters, the code gets a little ugly so that the logic is obscured. Try to remedy that by moving code to separate functions that have well-defined purposes. This patch splits out the simple ID decode functionality, where all the information regarding NAND size/blocksize/pagesize/oobsize/busw is encoded in the first two bytes of the ID string. Signed-off-by: Brian Norris Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse --- drivers/mtd/nand/nand_base.c | 51 +++++++++++++++++++++++++++----------------- 1 file changed, 31 insertions(+), 20 deletions(-) (limited to 'drivers/mtd') diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index e017af02da1c..4e1ea7283a95 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -2970,6 +2970,36 @@ static void nand_decode_ext_id(struct mtd_info *mtd, struct nand_chip *chip, } } +/* + * Old devices have chip data hardcoded in the device ID table. nand_decode_id + * decodes a matching ID table entry and assigns the MTD size parameters for + * the chip. + */ +static void nand_decode_id(struct mtd_info *mtd, struct nand_chip *chip, + struct nand_flash_dev *type, u8 id_data[8], + int *busw) +{ + int maf_id = id_data[0]; + + mtd->erasesize = type->erasesize; + mtd->writesize = type->pagesize; + mtd->oobsize = mtd->writesize / 32; + *busw = type->options & NAND_BUSWIDTH_16; + + /* + * Check for Spansion/AMD ID + repeating 5th, 6th byte since + * some Spansion chips have erasesize that conflicts with size + * listed in nand_ids table. + * Data sheet (5 byte ID): Spansion S30ML-P ORNAND (p.39) + */ + if (maf_id == NAND_MFR_AMD && id_data[4] != 0x00 && id_data[5] == 0x00 + && id_data[6] == 0x00 && id_data[7] == 0x00 + && mtd->writesize == 512) { + mtd->erasesize = 128 * 1024; + mtd->erasesize <<= ((id_data[3] & 0x03) << 1); + } +} + /* * Set the bad block marker/indicator (BBM/BBI) patterns according to some * heuristic patterns using various detected parameters (e.g., manufacturer, @@ -3084,26 +3114,7 @@ static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd, /* Decode parameters from extended ID */ nand_decode_ext_id(mtd, chip, id_data, &busw); } else { - /* - * Old devices have chip data hardcoded in the device id table. - */ - mtd->erasesize = type->erasesize; - mtd->writesize = type->pagesize; - mtd->oobsize = mtd->writesize / 32; - busw = type->options & NAND_BUSWIDTH_16; - - /* - * Check for Spansion/AMD ID + repeating 5th, 6th byte since - * some Spansion chips have erasesize that conflicts with size - * listed in nand_ids table. - * Data sheet (5 byte ID): Spansion S30ML-P ORNAND (p.39) - */ - if (*maf_id == NAND_MFR_AMD && id_data[4] != 0x00 && - id_data[5] == 0x00 && id_data[6] == 0x00 && - id_data[7] == 0x00 && mtd->writesize == 512) { - mtd->erasesize = 128 * 1024; - mtd->erasesize <<= ((id_data[3] & 0x03) << 1); - } + nand_decode_id(mtd, chip, type, id_data, &busw); } /* Get chip options */ chip->options |= type->options; -- cgit v1.2.2