On Fri, Jun 2, 2017 at 3:30 PM, Joshua Clayton <stillcompiling@xxxxxxxxx> wrote: > Describe an altera-passive-serial devicetree entry, required features > > Signed-off-by: Joshua Clayton <stillcompiling@xxxxxxxxx> > Acked-by: Rob Herring <robh@xxxxxxxxxx> Signed-off-by: Alan Tull <atull@xxxxxxxxxx> > --- > .../bindings/fpga/altera-passive-serial.txt | 29 ++++++++++++++++++++++ > 1 file changed, 29 insertions(+) > create mode 100644 Documentation/devicetree/bindings/fpga/altera-passive-serial.txt > > diff --git a/Documentation/devicetree/bindings/fpga/altera-passive-serial.txt b/Documentation/devicetree/bindings/fpga/altera-passive-serial.txt > new file mode 100644 > index 000000000000..48478bc07e29 > --- /dev/null > +++ b/Documentation/devicetree/bindings/fpga/altera-passive-serial.txt > @@ -0,0 +1,29 @@ > +Altera Passive Serial SPI FPGA Manager > + > +Altera FPGAs support a method of loading the bitstream over what is > +referred to as "passive serial". > +The passive serial link is not technically SPI, and might require extra > +circuits in order to play nicely with other SPI slaves on the same bus. > + > +See https://www.altera.com/literature/hb/cyc/cyc_c51013.pdf > + > +Required properties: > +- compatible: Must be one of the following: > + "altr,fpga-passive-serial", > + "altr,fpga-arria10-passive-serial" > +- reg: SPI chip select of the FPGA > +- nconfig-gpios: config pin (referred to as nCONFIG in the manual) > +- nstat-gpios: status pin (referred to as nSTATUS in the manual) > + > +Optional properties: > +- confd-gpios: confd pin (referred to as CONF_DONE in the manual) > + > +Example: > + fpga: fpga@0 { > + compatible = "altr,fpga-passive-serial"; > + spi-max-frequency = <20000000>; > + reg = <0>; > + nconfig-gpios = <&gpio4 9 GPIO_ACTIVE_LOW>; > + nstat-gpios = <&gpio4 11 GPIO_ACTIVE_LOW>; > + confd-gpios = <&gpio4 12 GPIO_ACTIVE_LOW>; > + }; > -- > 2.11.0 > -- 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
