On Tue, Jul 19, 2016 at 01:14:41PM -0600, Stephen Warren wrote: > From: Stephen Warren <swarren@xxxxxxxxxx> > > The BPMP implements some services which must be represented by separate > nodes. For example, it can provide access to certain I2C controllers, and > the I2C bindings represent each I2C controller as a device tree node. > Update the binding to describe how the BPMP supports this. > > Signed-off-by: Stephen Warren <swarren@xxxxxxxxxx> > --- > .../bindings/firmware/nvidia,tegra186-bpmp.txt | 23 ++++++++++++++++++++++ > 1 file changed, 23 insertions(+) > > diff --git a/Documentation/devicetree/bindings/firmware/nvidia,tegra186-bpmp.txt b/Documentation/devicetree/bindings/firmware/nvidia,tegra186-bpmp.txt > index 9a3864f56955..142d363406f6 100644 > --- a/Documentation/devicetree/bindings/firmware/nvidia,tegra186-bpmp.txt > +++ b/Documentation/devicetree/bindings/firmware/nvidia,tegra186-bpmp.txt > @@ -38,6 +38,24 @@ implemented by this node: > - .../reset/reset.txt > - <dt-bindings/reset/tegra186-reset.h> > > +The BPMP implements some services which must be represented by separate nodes. > +For example, it can provide access to certain I2C controllers, and the I2C > +bindings represent each I2C controller as a device tree node. Such nodes should > +be nested directly inside the main BPMP node. > + > +Software can determine whether a child node of the BPMP node represents a device > +by checking for a compatible property. Any node with a compatible property > +represents a device that can be instantiated. Nodes without a compatible > +property may be used to provide configuration information regarding the BPMP > +itself, although no such configuration nodes are currently defined by this > +binding. > + > +The BPMP firmware defines no single global name-/numbering-space for such > +services. Put another way, the numbering scheme for I2C buses is distinct from > +the numbering scheme for any other service the BPMP may provide (e.g. a future > +hypothetical SPI bus service). As such, child device nodes will have no reg > +property, and the BPMP node will have no #address-cells or #size-cells property. > + > The shared memory bindings for BPMP > ----------------------------------- > > @@ -78,4 +96,9 @@ bpmp { > #clock-cells = <1>; > #power-domain-cells = <1>; > #reset-cells = <1>; > + > + bpmp-i2c { Just 'i2c' here. With that: Acked-by: Rob Herring <robh@xxxxxxxxxx> > + compatible = "..."; > + ... > + }; > }; > -- > 2.9.2 > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html