From: Brian Norris <computersforpeace@gmail.com>
To: Zhi Li <lznuaa@gmail.com>
Cc: Huang Shijie <shijie8@gmail.com>, White Ding <bpqw@micron.com>,
linux-mtd@lists.infradead.org,
boris.brezillon@free-electrons.com
Subject: Re: mtd: nand: lock unlock function
Date: Wed, 5 Nov 2014 12:57:06 -0800 [thread overview]
Message-ID: <20141105205706.GP23619@ld-irv-0074> (raw)
In-Reply-To: <CAHrpEqSum1__d5Y1tysEzpa_MGuQSWfOW=m4idSxzCTdGbNKTQ@mail.gmail.com>
+
On Wed, Nov 05, 2014 at 02:31:34PM -0600, Zhi Li wrote:
> Does any know the reason why there are nand_lock and nand_unlock
> function in nand_base.c, but
>
> mtd->_lock = NULL;
> mtd->_unlock = NULL;
>
> Not set to nand_lock and nand_unlock?
Possible answers:
* Lack of testing
* The LOCK/UNLOCK opcodes are not supported by all vendors
* Even the vendors that support them don't do so consistently (not sure
about this one; I know Micron supports this in some cases)
* The opcodes aren't even documented (again, I'm not even sure about
this one; but many Micron datasheets I see don't mention LOCK/UNLOCK.
I recall that other similar lock/protection implementations are
secret to some extent, and are intentionally omitted from the
datasheets)
I'd be happy to be proven wrong on any of these points.
Brian
next prev parent reply other threads:[~2014-11-05 20:57 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-11-05 20:31 mtd: nand: lock unlock function Zhi Li
2014-11-05 20:57 ` Brian Norris [this message]
2014-11-05 22:00 ` Zhi Li
2014-11-06 0:50 ` Huang Shijie
2014-11-06 2:32 ` bpqw
2014-11-06 3:31 ` Zhi Li
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20141105205706.GP23619@ld-irv-0074 \
--to=computersforpeace@gmail.com \
--cc=boris.brezillon@free-electrons.com \
--cc=bpqw@micron.com \
--cc=linux-mtd@lists.infradead.org \
--cc=lznuaa@gmail.com \
--cc=shijie8@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox