From: Joel Stanley <joel@jms.id.au>
To: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>,
devicetree <devicetree@vger.kernel.org>,
linux-aspeed <linux-aspeed@lists.ozlabs.org>,
Wolfram Sang <wsa@the-dreams.de>,
Andrew Jeffery <andrew@aj.id.au>,
Benjamin Herrenschmidt <benh@kernel.crashing.org>,
OpenBMC Maillist <openbmc@lists.ozlabs.org>,
Brendan Higgins <brendanhiggins@google.com>,
Rob Herring <robh+dt@kernel.org>, Cedric Le Goater <clg@kaod.org>,
Tao Ren <taoren@fb.com>,
Linux ARM <linux-arm-kernel@lists.infradead.org>,
linux-i2c@vger.kernel.org
Subject: Re: [PATCH] i2c: aspeed: fix master pending state handling
Date: Thu, 10 Oct 2019 06:48:15 +0000 [thread overview]
Message-ID: <CACPK8XfKCSNsQJa2J2jKZJ7LGZh3zXAOfBYnp5X0w=TH4JfSpQ@mail.gmail.com> (raw)
In-Reply-To: <20191009212034.20325-1-jae.hyun.yoo@linux.intel.com>
On Wed, 9 Oct 2019 at 21:20, Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com> wrote:
>
> In case of master pending state, it should not trigger a master
> command, otherwise data could be corrupted because this H/W shares
> the same data buffer for slave and master operations. It also means
> that H/W command queue handling is unreliable because of the buffer
> sharing issue. To fix this issue, it clears command queue if a
> master command is queued in pending state to use S/W solution
> instead of H/W command queue handling. Also, it refines restarting
> mechanism of the pending master command.
>
> Fixes: 2e57b7cebb98 ("i2c: aspeed: Add multi-master use case support")
> Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>
Acked-by: Joel Stanley <joel@jms.id.au>
While reviewing I was concerned about the locking in
aspeed_i2c_master_xfer. It's a bit hairy, and I am not convinced it is
without bugs.
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2019-10-10 6:48 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-09 21:20 [PATCH] i2c: aspeed: fix master pending state handling Jae Hyun Yoo
2019-10-10 0:32 ` Brendan Higgins
2019-10-10 1:26 ` Tao Ren
2019-10-10 6:37 ` Wolfram Sang
2019-10-10 6:48 ` Joel Stanley [this message]
2019-10-10 18:22 ` Jae Hyun Yoo
2019-10-10 21:20 ` Tao Ren
2019-10-10 22:04 ` Jae Hyun Yoo
2019-10-10 23:11 ` Tao Ren
2019-10-10 23:16 ` Jae Hyun Yoo
2019-10-10 23:24 ` Tao Ren
2019-10-10 23:29 ` Tao Ren
2019-10-10 23:52 ` Jae Hyun Yoo
2019-10-16 19:20 ` Brendan Higgins
2019-10-21 12:09 ` Wolfram Sang
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='CACPK8XfKCSNsQJa2J2jKZJ7LGZh3zXAOfBYnp5X0w=TH4JfSpQ@mail.gmail.com' \
--to=joel@jms.id.au \
--cc=andrew@aj.id.au \
--cc=benh@kernel.crashing.org \
--cc=brendanhiggins@google.com \
--cc=clg@kaod.org \
--cc=devicetree@vger.kernel.org \
--cc=jae.hyun.yoo@linux.intel.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-aspeed@lists.ozlabs.org \
--cc=linux-i2c@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=openbmc@lists.ozlabs.org \
--cc=robh+dt@kernel.org \
--cc=taoren@fb.com \
--cc=wsa@the-dreams.de \
/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;
as well as URLs for NNTP newsgroup(s).