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+Xilinx XADC device driver
+
+This binding document describes the bindings for the Xilinx 7 Series XADC as well
+as the UltraScale/UltraScale+ System Monitor.
+
+The Xilinx XADC is an ADC that can be found in the Series 7 FPGAs from Xilinx.
+The XADC has a DRP interface for communication. Currently two different
+frontends for the DRP interface exist. One that is only available on the ZYNQ
+family as a hardmacro in the SoC portion of the ZYNQ. The other one is available
+on all series 7 platforms and is a softmacro with a AXI interface. This binding
+document describes the bindings for both of them since the bindings are very
+similar.
+
+The Xilinx System Monitor is an ADC that is found in the UltraScale and
+UltraScale+ FPGAs from Xilinx. The System Monitor provides a DRP interface for
+communication. Xilinx provides a standard IP core that can be used to access the
+System Monitor through an AXI interface in the FPGA fabric. This IP core is
+called the Xilinx System Management Wizard. This document describes the bindings
+for this IP.
+
+Required properties:
+ - compatible: Should be one of
+ * "xlnx,zynq-xadc-1.00.a": When using the ZYNQ device
+ configuration interface to interface to the XADC hardmacro.
+ * "xlnx,axi-xadc-1.00.a": When using the axi-xadc pcore to
+ interface to the XADC hardmacro.
+ * "xlnx,system-management-wiz-1.3": When using the
+ Xilinx System Management Wizard fabric IP core to access the
+ UltraScale and UltraScale+ System Monitor.
+ - reg: Address and length of the register set for the device
+ - interrupts: Interrupt for the XADC control interface.
+ - clocks: When using the ZYNQ this must be the ZYNQ PCAP clock,
+ when using the axi-xadc or the axi-system-management-wizard this must be
+ the clock that provides the clock to the AXI bus interface of the core.
+
+Optional properties:
+ - xlnx,external-mux:
+ * "none": No external multiplexer is used, this is the default
+ if the property is omitted.
+ * "single": External multiplexer mode is used with one
+ multiplexer.
+ * "dual": External multiplexer mode is used with two
+ multiplexers for simultaneous sampling.
+ - xlnx,external-mux-channel: Configures which pair of pins is used to
+ sample data in external mux mode.
+ Valid values for single external multiplexer mode are:
+ 0: VP/VN
+ 1: VAUXP[0]/VAUXN[0]
+ 2: VAUXP[1]/VAUXN[1]
+ ...
+ 16: VAUXP[15]/VAUXN[15]
+ Valid values for dual external multiplexer mode are:
+ 1: VAUXP[0]/VAUXN[0] - VAUXP[8]/VAUXN[8]
+ 2: VAUXP[1]/VAUXN[1] - VAUXP[9]/VAUXN[9]
+ ...
+ 8: VAUXP[7]/VAUXN[7] - VAUXP[15]/VAUXN[15]
+
+ This property needs to be present if the device is configured for
+ external multiplexer mode (either single or dual). If the device is
+ not using external multiplexer mode the property is ignored.
+ - xnlx,channels: List of external channels that are connected to the ADC
+ Required properties:
+ * #address-cells: Should be 1.
+ * #size-cells: Should be 0.
+
+ The child nodes of this node represent the external channels which are
+ connected to the ADC. If the property is no present no external
+ channels will be assumed to be connected.
+
+ Each child node represents one channel and has the following
+ properties:
+ Required properties:
+ * reg: Pair of pins the channel is connected to.
+ 0: VP/VN
+ 1: VAUXP[0]/VAUXN[0]
+ 2: VAUXP[1]/VAUXN[1]
+ ...
+ 16: VAUXP[15]/VAUXN[15]
+ Note each channel number should only be used at most
+ once.
+ Optional properties:
+ * xlnx,bipolar: If set the channel is used in bipolar
+ mode.
+
+
+Examples:
+ xadc@f8007100 {
+ compatible = "xlnx,zynq-xadc-1.00.a";
+ reg = <0xf8007100 0x20>;
+ interrupts = <0 7 4>;
+ interrupt-parent = <&gic>;
+ clocks = <&pcap_clk>;
+
+ xlnx,channels {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ channel@0 {
+ reg = <0>;
+ };
+ channel@1 {
+ reg = <1>;
+ };
+ channel@8 {
+ reg = <8>;
+ };
+ };
+ };
+
+ xadc@43200000 {
+ compatible = "xlnx,axi-xadc-1.00.a";
+ reg = <0x43200000 0x1000>;
+ interrupts = <0 53 4>;
+ interrupt-parent = <&gic>;
+ clocks = <&fpga1_clk>;
+
+ xlnx,channels {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ channel@0 {
+ reg = <0>;
+ xlnx,bipolar;
+ };
+ };
+ };
+
+ adc@80000000 {
+ compatible = "xlnx,system-management-wiz-1.3";
+ reg = <0x80000000 0x1000>;
+ interrupts = <0 81 4>;
+ interrupt-parent = <&gic>;
+ clocks = <&fpga1_clk>;
+
+ xlnx,channels {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ channel@0 {
+ reg = <0>;
+ xlnx,bipolar;
+ };
+ };
+ };