[PATCH] mtd/nand: Spansion S30MLxxxP support

[Brian Norris]

Some Spansion chips have a method for determining eraseblock size that
is incompatible with similar ID chips of other sizes. This implements
some heuristic detection of these differences.

Note that I am unsure about the wraparound nature of the ID string here.
I have not been able to fully test this with the physical chip.
Essentially, the rule is correct, but the ID string detection may fail
here. Let me know if anyone can fix this.

Signed-off-by: Brian Norris <norris at broadcom.com>
---
 drivers/mtd/nand/nand_base.c |   11 +++++++++++
 1 files changed, 11 insertions(+), 0 deletions(-)

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index a3c7473..66f4412 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -2899,6 +2899,17 @@ static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd,
 		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[5] == 0x01 &&
+				id_data[6] == 0x01)
+			mtd->erasesize = (128 * 1024) << ((id_data[3] & 0x03)
+					<< 1);
 	}
 
 	/* Try to identify manufacturer */
-- 
1.7.0.4