Read Status and Read ID require tWHR before reading the first data.
Insert a very short wait to make sure to meet the spec.

I have not seen any problem report for now, but nand_command() and
nand_command_lP() are generic hooks, so it makes sense to implement
fail-safe code here.

Signed-off-by: Masahiro Yamada <yamada.masah...@socionext.com>
---

 drivers/mtd/nand/nand_base.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index b1cf32c..55c0ba5 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -742,9 +742,12 @@ static void nand_command(struct mtd_info *mtd, unsigned 
int command,
        case NAND_CMD_ERASE1:
        case NAND_CMD_ERASE2:
        case NAND_CMD_SEQIN:
+       case NAND_CMD_SET_FEATURES:
+               return;
+
        case NAND_CMD_STATUS:
        case NAND_CMD_READID:
-       case NAND_CMD_SET_FEATURES:
+               ndelay(200);    /* tWHR */
                return;
 
        case NAND_CMD_RESET:
@@ -871,9 +874,12 @@ static void nand_command_lp(struct mtd_info *mtd, unsigned 
int command,
        case NAND_CMD_ERASE1:
        case NAND_CMD_ERASE2:
        case NAND_CMD_SEQIN:
+       case NAND_CMD_SET_FEATURES:
+               return;
+
        case NAND_CMD_STATUS:
        case NAND_CMD_READID:
-       case NAND_CMD_SET_FEATURES:
+               ndelay(200);    /* tWHR */
                return;
 
        case NAND_CMD_RNDIN:
-- 
2.7.4

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