[ 3.5.yuz extended stable ] Patch "mtd: nand: allow NAND_NO_SUBPAGE_WRITE to be set from driver" has been added to staging queue

Herton Ronaldo Krzesinski herton.krzesinski at canonical.com
Thu Nov 15 05:48:18 UTC 2012

This is a note to let you know that I have just added a patch titled

    mtd: nand: allow NAND_NO_SUBPAGE_WRITE to be set from driver

to the linux-3.5.y-queue branch of the 3.5.yuz extended stable tree 
which can be found at:


If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.yuz tree, see



>From 2cce1c9d5ff55f34f84c4b27bf505734651d6dd9 Mon Sep 17 00:00:00 2001
From: Brian Norris <computersforpeace at gmail.com>
Date: Fri, 13 Jul 2012 09:28:24 -0700
Subject: [PATCH] mtd: nand: allow NAND_NO_SUBPAGE_WRITE to be set from driver

commit bf7a01bf7987b63b121d572b240c132ec44129c4 upstream.

The NAND_CHIPOPTIONS_MSK has limited utility and is causing real bugs. It
silently masks off at least one flag that might be set by the driver
(NAND_NO_SUBPAGE_WRITE). This breaks the GPMI NAND driver and possibly

Really, as long as driver writers exercise a small amount of care with
NAND_* options, this mask is not necessary at all; it was only here to
prevent certain options from accidentally being set by the driver. But the
original thought turns out to be a bad idea occasionally. Thus, kill it.

Note, this patch fixes some major gpmi-nand breakage.

Signed-off-by: Brian Norris <computersforpeace at gmail.com>
Tested-by: Huang Shijie <shijie8 at gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy at linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse at intel.com>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski at canonical.com>
 drivers/mtd/nand/nand_base.c |    8 +++-----
 include/linux/mtd/nand.h     |    3 ---
 2 files changed, 3 insertions(+), 8 deletions(-)

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index a11253a..c429abd 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -2914,8 +2914,7 @@ static int nand_flash_detect_onfi(struct mtd_info *mtd, struct nand_chip *chip,
 	if (le16_to_cpu(p->features) & 1)
 		*busw = NAND_BUSWIDTH_16;

-	chip->options &= ~NAND_CHIPOPTIONS_MSK;
+	chip->options |= NAND_NO_READRDY;

 	pr_info("ONFI flash detected\n");
 	return 1;
@@ -3080,9 +3079,8 @@ static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd,
 			mtd->erasesize <<= ((id_data[3] & 0x03) << 1);
-	/* Get chip options, preserve non chip based options */
-	chip->options &= ~NAND_CHIPOPTIONS_MSK;
-	chip->options |= type->options & NAND_CHIPOPTIONS_MSK;
+	/* Get chip options */
+	chip->options |= type->options;

 	 * Check if chip is not a Samsung device. Do not clear the
diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index 57977c6..e5cf2c8 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -212,9 +212,6 @@ typedef enum {
 #define NAND_SUBPAGE_READ(chip) ((chip->ecc.mode == NAND_ECC_SOFT) \
 					&& (chip->page_shift > 9))

-/* Mask to zero out the chip options, which come from the id table */
-#define NAND_CHIPOPTIONS_MSK	0x0000ffff
 /* Non chip related options */
 /* This option skips the bbt scan during initialization. */
 #define NAND_SKIP_BBTSCAN	0x00010000

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