Messages in this thread | | | Date | Wed, 6 May 2009 12:33:07 +0300 | From | Ville Syrjälä <> | Subject | Re: [PATCH] w1-gpio: add external pull-up enable callback |
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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/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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