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+Altera FPGAs in passive serial mode
+===================================
+
+This binding defines the control interface to Altera FPGAs in
+passive serial mode. This is used to upload the firmware and
+to start the FPGA.
+
+Required properties:
+- ``compatible``: shall be ``"altr,fpga-passive-serial"`` or
+  ``"altr,fpga-arria10-passive-serial"`` for Arria 10
+- ``reg``: SPI chip select
+- ``nstat-gpios``: Specify GPIO for controlling the nstat pin
+- ``confd-gpios``: Specify GPIO for controlling the confd pin
+- ``nconfig-gpios``: Specify GPIO for controlling the nconfig pin
+
+Example:
+
+.. code-block:: none
+
+	fpga@0 {
+		compatible = "altr,fpga-passive-serial";
+		nstat-gpios = <&gpio4 18 0>;
+		confd-gpios = <&gpio4 19 0>;
+		nconfig-gpios = <&gpio4 20 0>;
+		spi-max-frequency = <10000000>;
+		reg = <0>;
+	};