Messages in this thread | | | Date | Fri, 14 Dec 2012 09:06:49 -0700 | From | Stephen Warren <> | Subject | Re: [PATCH 1/2] i2c-core: Add gpio based bus arbitration implementation |
| |
On 12/13/2012 10:50 PM, Naveen Krishna Chatradhi wrote: > The arbitrator is a general purpose function which uses two GPIOs to > communicate with another device to claim/release a bus.
> diff --git a/Documentation/devicetree/bindings/i2c/arbitrator-i2c.txt b/Documentation/devicetree/bindings/i2c/arbitrator-i2c.txt > new file mode 100644 > index 0000000..cb91ea8 > --- /dev/null > +++ b/Documentation/devicetree/bindings/i2c/arbitrator-i2c.txt > @@ -0,0 +1,56 @@ > +Device-Tree bindings for i2c gpio based bus arbitrator > + > +bus-arbitration-gpios : > + Two GPIOs to use with the GPIO-based bus arbitration protocol > +(see below). > +The first should be an output, and is used to claim the I2C bus, > +the second should be an input, and signals that the other side (Client) > +wants to claim the bus. This allows two masters to share the same I2C bus.
I'm confused why this is even needed; the I2C protocol itself defines how multi-master is supposed to work, just using the regular SCL/SDA lines.
| |