[PATCH v2 3/3] mtd: nand: introduce a READMODE command

[Gupta, Pekon]

Hi Gerhard,

>From: Gerhard Sittig [mailto:gsi at denx.de]
>
>the nand_command_lp() implementation derives a "READPAGE" sequence from
>a passed in READ0 opcode, i.e. emits a sequence of READ0 _and_ READSTART
>commands in this case
>
>introduce a "READMODE" command which sends the READ0 opcode to the chip
>exclusively and doesn't send the READSTART opcode
>
>such a "READMODE" command is useful in the context of on-die-ECC support
>where a sequence of READ0, READSTART, STATUS, READ0 is required; having
>support for READMODE in the common nand_command_lp() routine avoids the
>need for duplication and open coded cmd_ctrl() calls
>
>for the non-"large page" setup (i.e. the nand_command() routine) both
>commands "READMODE" and "READ0" are identical, "READSTART" exclusively
>applies to large page configurations
>
>Signed-off-by: Gerhard Sittig <gsi at denx.de>
>---
>changes in v2:
>- update the commmit message to discuss that for the nand_command()
>  routine READMODE results in identical behaviour as READ0
>- rephrase the NAND_CMD_READMODE command to better reflect that it
>  re-uses the NAND_CMD_READ0 opcode plus has high bits set
>
> drivers/mtd/nand/nand_base.c |    4 +++-
> include/linux/mtd/nand.h     |   11 +++++++++++
> 2 files changed, 14 insertions(+), 1 deletion(-)
>
>diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
>index 7108191b1598..50b8a2a93b4f 100644
>--- a/drivers/mtd/nand/nand_base.c
>+++ b/drivers/mtd/nand/nand_base.c
>@@ -711,7 +711,8 @@ static void nand_command_lp(struct mtd_info *mtd, unsigned int command,
>
> 	/*
> 	 * Program and erase have their own busy handlers status, sequential
>-	 * in and status need no delay.
>+	 * in and status need no delay, read mode just reverts back to
>+	 * data output after a status command and needs no read start.
> 	 */
> 	switch (command) {
>
>@@ -722,6 +723,7 @@ static void nand_command_lp(struct mtd_info *mtd, unsigned int command,
> 	case NAND_CMD_SEQIN:
> 	case NAND_CMD_RNDIN:
> 	case NAND_CMD_STATUS:
>+	case NAND_CMD_READMODE:
> 		return;
>
> 	case NAND_CMD_RESET:

You probably missed doing same change in nand_command() also.

with regards, pekon