From: "Ville Syrjälä" <syrjala@sci.fi>
To: Daniel Mack <daniel@caiaq.de>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] w1-gpio: add external pull-up enable callback
Date: Wed, 6 May 2009 12:33:07 +0300 [thread overview]
Message-ID: <20090506093307.GC17782@sci.fi> (raw)
In-Reply-To: <1241527413-22920-1-git-send-email-daniel@caiaq.de>
On Tue, May 05, 2009 at 02:43:33PM +0200, Daniel Mack wrote:
> On embedded devices, sleep mode conditions can be tricky to handle,
> Especially when processors tend to pull-down the w1 bus during sleep.
> Bus slaves (such as the ds2760) may interpret this as a reason for
> power-down conditions and entirely switch off the device.
>
> This patch adds a callback function pointer to let users switch on and
> off the external pull-up resistor. This lets the outside world know
> whether the processor is currently actively driving the bus or not.
Looks simple enough but I wonder if you could just do this from the
platform code. I suppose the downside would be that you would enable the
pullup even if w1-gpio is not loaded.
--
Ville Syrjälä
syrjala@sci.fi
http://www.sci.fi/~syrjala/
next prev parent reply other threads:[~2009-05-06 9:33 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-05-05 12:43 [PATCH] w1-gpio: add external pull-up enable callback Daniel Mack
2009-05-06 9:33 ` Ville Syrjälä [this message]
2009-05-06 9:34 ` Daniel Mack
2009-05-06 20:28 ` Ville Syrjälä
2009-05-07 1:30 ` Daniel Mack
2009-05-08 18:19 ` Ville Syrjälä
2009-05-08 20:13 ` Daniel Mack
2009-05-08 20:53 ` Evgeniy Polyakov
2009-05-12 13:56 ` Daniel Mack
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=20090506093307.GC17782@sci.fi \
--to=syrjala@sci.fi \
--cc=daniel@caiaq.de \
--cc=linux-kernel@vger.kernel.org \
/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