mtd: nand: add NAND_NEED_SCRAMBLING option flag

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Gitweb:     http://git.infradead.org/?p=mtd-2.6.git;a=commit;h=c03d996900f9d063b47ef7462885a9085c8a587f
Commit:     c03d996900f9d063b47ef7462885a9085c8a587f
Parent:     23819f2eaab87080b0190ed94a0728fc8ea84711
Author:     Boris BREZILLON <boris.brezillon at free-electrons.com>
AuthorDate: Wed Dec 2 12:01:05 2015 +0100
Committer:  Brian Norris <computersforpeace at gmail.com>
CommitDate: Fri Jan 22 16:36:54 2016 -0800

    mtd: nand: add NAND_NEED_SCRAMBLING option flag
    
    Some MLC NANDs are sensitive to repeated patterns and require data to be
    scrambled in order to limit the number of bitflips.
    Add a new flag to let the NAND controller know about this constraint.
    
    Signed-off-by: Boris Brezillon <boris.brezillon at free-electrons.com>
    Signed-off-by: Brian Norris <computersforpeace at gmail.com>
---
 include/linux/mtd/nand.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index bdd68e2..a13dfd5 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -168,6 +168,12 @@ typedef enum {
 /* Device supports subpage reads */
 #define NAND_SUBPAGE_READ	0x00001000
 
+/*
+ * Some MLC NANDs need data scrambling to limit bitflips caused by repeated
+ * patterns.
+ */
+#define NAND_NEED_SCRAMBLING	0x00002000
+
 /* Options valid for Samsung large page devices */
 #define NAND_SAMSUNG_LP_OPTIONS NAND_CACHEPRG