[PATCH v3 1/5] dt-bindings: fsi: Document binding for the fsi-master-ast-cf "device"

Benjamin Herrenschmidt benh at kernel.crashing.org
Tue Jul 17 14:12:15 AEST 2018


On Mon, 2018-07-16 at 09:33 -0600, Rob Herring wrote:
> On Thu, Jul 12, 2018 at 01:48:43PM +1000, Benjamin Herrenschmidt wrote:
> > This isn't per-se a real device, it's a pseudo-device that
> > represents the use of the Aspeed built-in ColdFire to
> > implement the FSI protocol by bitbanging the GPIOs instead
> > of doing it from the ARM core.
> > 
> > Thus it's a drop-in replacement for the existing
> > fsi-master-gpio pseudo-device for use on systems based
> > on the Aspeed chips. It has most of the same properties,
> > plus some more needed to operate the coprocessor.
> > 
> > Signed-off-by: Benjamin Herrenschmidt <benh at kernel.crashing.org>
> > ---
> >  .../bindings/fsi/fsi-master-ast-cf.txt        | 36 +++++++++++++++++++
> >  1 file changed, 36 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/fsi/fsi-master-ast-cf.txt
> > 
> > diff --git a/Documentation/devicetree/bindings/fsi/fsi-master-ast-cf.txt b/Documentation/devicetree/bindings/fsi/fsi-master-ast-cf.txt
> > new file mode 100644
> > index 000000000000..431bf8a423ce
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/fsi/fsi-master-ast-cf.txt
> > @@ -0,0 +1,36 @@
> > +Device-tree bindings for ColdFire offloaded gpio-based FSI master driver
> > +------------------------------------------------------------------------
> > +
> > +Required properties:
> > + - compatible =
> > +	"aspeed,ast2400-cf-fsi-master" for an AST2400 based system
> > +   or
> > +	"aspeed,ast2500-cf-fsi-master" for an AST2500 based system
> > +
> > + - clock-gpios = <gpio-descriptor>;	: GPIO for FSI clock
> > + - data-gpios = <gpio-descriptor>;	: GPIO for FSI data signal
> > + - enable-gpios = <gpio-descriptor>;	: GPIO for enable signal
> > + - trans-gpios = <gpio-descriptor>;	: GPIO for voltage translator enable
> > + - mux-gpios = <gpio-descriptor>;	: GPIO for pin multiplexing with other
> > +                                          functions (eg, external FSI masters)
> > + - memory-region = <phandle>;		: Reference to the reserved memory for
> > +                                          the ColdFire. Must be 2M aligned on
> > +					  AST2400 and 1M aligned on AST2500
> > + - aspeed,sram = <phandle>;		: Reference to the SRAM node.
> > + - aspeed,cvic = <phandle>;		: Reference to the CVIC node.
> > +
> > +Examples:
> > +
> > +    fsi-master {
> > +        compatible = "aspeed,ast2500-cf-fsi-master", "fsi-master";
> > +
> > +	clock-gpios = <&gpio 0>;
> > +        data-gpios = <&gpio 1>;
> > +        enable-gpios = <&gpio 2>;
> > +        trans-gpios = <&gpio 3>;
> > +        mux-gpios = <&gpio 4>;
> > +
> > +	memory-region = <&coldfire_memory>;
> > +	sram = <&sram>;
> > +	cvic = <&cvic>;
> 
> Need to update the example. With that

Ah right, thanks. The next spin will have that fixed and will go into
the fsi tree.

> Reviewed-by: Rob Herring <robh at kernel.org>


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