From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp9.mail.ru ([94.100.176.54]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1UFITv-0006oR-Qt for linux-mtd@lists.infradead.org; Tue, 12 Mar 2013 06:14:41 +0000 From: Alexander Shiyan To: linux-mtd@lists.infradead.org Subject: [RFC RESEND] mtd: nand_base: Make Diskonchip work again Date: Tue, 12 Mar 2013 10:14:24 +0400 Message-Id: <1363068864-5376-1-git-send-email-shc_work@mail.ru> Cc: Artem Bityutskiy , Brian Norris , David Woodhouse , Alexander Shiyan List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , According to my post (http://permalink.gmane.org/gmane.linux.drivers.mtd/45657), I created a patch to fix the DiskOnChip regression. Patch partially revert "mtd: nand: kill NAND_NO_READRDY". We create NAND_NEED_READDRY option as a replacement NAND_NO_READRDY but with different logic, and restore RDY expectations in reading function, if this option is set. At least, Disconchip works again, so probably it can help in solving other NAND-related bugs in the latest kernels. Signed-off-by: Alexander Shiyan --- drivers/mtd/nand/diskonchip.c | 1 + drivers/mtd/nand/nand_base.c | 16 ++++++++++++++++ include/linux/mtd/nand.h | 2 ++ 3 files changed, 19 insertions(+), 0 deletions(-) diff --git a/drivers/mtd/nand/diskonchip.c b/drivers/mtd/nand/diskonchip.c index 81fa578..19992f2 100644 --- a/drivers/mtd/nand/diskonchip.c +++ b/drivers/mtd/nand/diskonchip.c @@ -1580,6 +1580,7 @@ static int __init doc_probe(unsigned long physadr) nand->dev_ready = doc200x_dev_ready; nand->waitfunc = doc200x_wait; nand->block_bad = doc200x_block_bad; + nand->options = NAND_NEED_READRDY; nand->ecc.hwctl = doc200x_enable_hwecc; nand->ecc.calculate = doc200x_calculate_ecc; nand->ecc.correct = doc200x_correct_data; 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 @@ static int nand_do_read_ops(struct mtd_info *mtd, loff_t from, 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 @@ static int nand_do_read_oob(struct mtd_info *mtd, loff_t from, 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; diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h index 7ccb3c5..1c13582 100644 --- a/include/linux/mtd/nand.h +++ b/include/linux/mtd/nand.h @@ -187,6 +187,8 @@ typedef enum { * This happens with the Renesas AG-AND chips, possibly others. */ #define BBT_AUTO_REFRESH 0x00000080 +/* Chip require ready check on read */ +#define NAND_NEED_READRDY 0x00000100 /* Chip does not allow subpage writes */ #define NAND_NO_SUBPAGE_WRITE 0x00000200 -- 1.7.3.4