mtd: nand: reintroduce NAND_NO_READRDY as NAND_NEED_READRDY

This partially reverts commit 1696e6bc2ae83734e64e206ac99766ea19e9a14e
("mtd: nand: kill NAND_NO_READRDY").

In that patch I overlooked a few things.

The original documentation for NAND_NO_READRDY included "True for all
large page devices, as they do not support autoincrement." I was
conflating "not support autoincrement" with the NAND_NO_AUTOINCR option,
which was in fact doing nothing. So, when I dropped NAND_NO_AUTOINCR, I
concluded that I then could harmlessly drop NAND_NO_READRDY. But of
course the fact the NAND_NO_AUTOINCR was doing nothing didn't mean
NAND_NO_READRDY was doing nothing...

So, NAND_NO_READRDY is re-introduced as NAND_NEED_READRDY and applied
only to those few remaining small-page NAND which needed it in the first
place.

Cc: stable@kernel.org [3.5+]
Reported-by: Alexander Shiyan <shc_work@mail.ru>
Tested-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 4321415..42c6392 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -1523,6 +1523,14 @@
 					oobreadlen -= toread;
 				}
 			}
+
+			if (chip->options & NAND_NEED_READRDY) {
+				/* Apply delay or wait for ready/busy pin */
+				if (!chip->dev_ready)
+					udelay(chip->chip_delay);
+				else
+					nand_wait_ready(mtd);
+			}
 		} else {
 			memcpy(buf, chip->buffers->databuf + col, bytes);
 			buf += bytes;
@@ -1787,6 +1795,14 @@
 		len = min(len, readlen);
 		buf = nand_transfer_oob(chip, buf, ops, len);
 
+		if (chip->options & NAND_NEED_READRDY) {
+			/* Apply delay or wait for ready/busy pin */
+			if (!chip->dev_ready)
+				udelay(chip->chip_delay);
+			else
+				nand_wait_ready(mtd);
+		}
+
 		readlen -= len;
 		if (!readlen)
 			break;