[PATCH v4 3/5] mtd: nand: Enable subpage-reads on flashes with on-die ECC enabled.

[David Mosberger]

As far as we know, all flash chips with the Micron on-die ECC hardware
have subpage capability, so enable it for that case.

Signed-off-by: David Mosberger <davidm at egauge.net>
---
 drivers/mtd/nand/nand_base.c |    9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 7047e9f5..435ef44 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -4185,8 +4185,13 @@ int nand_scan_tail(struct mtd_info *mtd)
 	/* Invalidate the pagebuffer reference */
 	chip->pagebuf = -1;
 
-	/* Large page NAND with SOFT_ECC should support subpage reads */
-	if ((ecc->mode == NAND_ECC_SOFT) && (chip->page_shift > 9))
+	/*
+	 * Large page NAND with SOFT_ECC or on-die ECC should support
+	 * subpage reads.
+	 */
+	if (((ecc->mode == NAND_ECC_SOFT)
+	     || (chip->ecc.mode == NAND_ECC_HW_ON_DIE))
+	    && (chip->page_shift > 9))
 		chip->options |= NAND_SUBPAGE_READ;
 
 	/* Fill in remaining MTD driver data */
-- 
1.7.9.5