From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joshua Clayton Subject: [PATCH v8 1/3] doc: dt: add cyclone-ps-spi binding document Date: Mon, 23 Jan 2017 14:51:04 -0800 Message-ID: <6b7883678d1e343d103302c77863bf69ca836637.1485211400.git.stillcompiling@gmail.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: In-Reply-To: References: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Alan Tull , Moritz Fischer , Russell King , Shawn Guo , Sascha Hauer , Fabio Estevam Cc: Mark Rutland , devicetree@vger.kernel.org, Joshua Clayton , linux-fpga@vger.kernel.org, linux-kernel@vger.kernel.org, Rob Herring , Anatolij Gustschin , linux-arm-kernel@lists.infradead.org List-Id: devicetree@vger.kernel.org Describe a cyclone-ps-spi devicetree entry, required features Signed-off-by: Joshua Clayton Acked-by: Rob Herring --- .../bindings/fpga/altera-passive-serial.txt | 25 ++++++++++++++++++++++ 1 file changed, 25 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 0000000..b5f0bb5 --- /dev/null +++ b/Documentation/devicetree/bindings/fpga/altera-passive-serial.txt @@ -0,0 +1,25 @@ +Altera Cyclone Passive Serial SPI FPGA Manager + +Altera Cyclone 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: should contain "altr,fpga-passive-serial" +- reg: spi chip select of the FPGA +- nstat-gpios: status pin (referred to as nSTATUS in the cyclone manual) +- nconfig-gpios: config pin (referred to as nCONFIG in the cyclone manual) +- confd-gpios: confd pin (referred to as CONF_DONE in the cyclone manual) + +Example: + fpga_spi: evi-fpga-spi@0 { + compatible = "altr,cyclone-ps-spi-fpga-mgr"; + 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>; + }; -- 2.9.3