Re: [PATCH] w1-gpio: add external pull-up enable callback

From: Ville Syrjälä
Date: Wed May 06 2009 - 16:28:32 EST


On Wed, May 06, 2009 at 11:34:45AM +0200, Daniel Mack wrote:
> On Wed, May 06, 2009 at 12:33:07PM +0300, Ville Syrjälä wrote:
> > 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.
>
> That's right. Hence I put it where I believe it belongs to.

Well, if you think you need it who am I to argue :)

Acked-by: Ville Syrjälä <syrjala@xxxxxx>

--
Ville Syrjälä
syrjala@xxxxxx
http://www.sci.fi/~syrjala/
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