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Date: Tue, 23 Apr 2013 14:15:56 +0800
From: Huang Shijie <b32955@freescale.com>
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To: Brian Norris <computersforpeace@gmail.com>
Subject: Re: [PATCH v2 3/8] mtd: get the ECC info from the Extended Parameter
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=E4=BA=8E 2013=E5=B9=B404=E6=9C=8823=E6=97=A5 05:22, Brian Norris =E5=86=99=
=E9=81=93:
> You never sent a command to the chip. How can you expect to read from i=
t?
>
> It seems that you are writing this function with the assumption of a
> particular calling context (a context in which the last command was
> CMD_PARAM). IMO, it would make a lot more sense that this function
> actually send its own CMD_PARAM followed by either X bytes of skipped
> read_buf() or a change read column command. Then it doesn't need the
> "last" argument, and its usage makes much more sense.
>
I finally find why i can not use the CHANGE READ COLUMN command:

When we detect the ONFI nand, we actually use the nand_command() to=20
issue the command which
does not works with CHANGE READ COLUMN command.

I use the nand_command_lp() to issue the CHANGE READ COLUMN command, it=20
works fine.

I can remove the "last" argument now.

thanks Brian.

Huang Shijie