From: David Brownell <david-b@pacbell.net>
To: Mark Jackson <mpfj@mimc.co.uk>
Cc: Alessandro Zummo <alessandro.zummo@towertech.it>,
rtc-linux@googlegroups.com, lkml <linux-kernel@vger.kernel.org>,
spi-devel-general@lists.sourceforge.net
Subject: Re: [PATCH] Add Dallas DS1390 RTC chip
Date: Fri, 17 Oct 2008 08:29:06 -0700 [thread overview]
Message-ID: <200810170829.06699.david-b@pacbell.net> (raw)
In-Reply-To: <48F8467C.5010902@mimc.co.uk>
On Friday 17 October 2008, Mark Jackson wrote:
> >> + /* Can tx_buf and rx_buf be equal? The doc in spi.h is not sure... */
> >> + xfer.tx_buf = chip->tx_buf;
> >> + xfer.rx_buf = chip->rx_buf;
> >
> > you use the same buffer a few functions below. either
> > one way or the other. please investigate with the spi subsystem maintainer.
>
> David,
>
> Just to double check (as per Alessandro's suggestion), is this okay use of the
> spi buffers ?
Yes. That comment deserves to be updated.
SPI does bi-directional I/O, and the underlying controller
should be able to just replace the contents of a buffer
with a spi_transfer that uses the same rx and tx buffers.
- Dave
next prev parent reply other threads:[~2008-10-17 15:29 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <48F452BE.2030901@mimc.co.uk>
2008-10-14 8:17 ` Alessandro Zummo
2008-10-17 8:02 ` Mark Jackson
2008-10-17 15:29 ` David Brownell [this message]
2008-10-17 18:57 ` Mark Jackson
2008-10-07 13:44 Mark Jackson
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=200810170829.06699.david-b@pacbell.net \
--to=david-b@pacbell.net \
--cc=alessandro.zummo@towertech.it \
--cc=linux-kernel@vger.kernel.org \
--cc=mpfj@mimc.co.uk \
--cc=rtc-linux@googlegroups.com \
--cc=spi-devel-general@lists.sourceforge.net \
/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
Powered by JetHome