From: Alan Tull <redacted>

Add bindings documentation for Altera SOCFPGA bridges:
 * fpga2sdram
 * fpga2hps
 * hps2fpga
 * lwhps2fpga

Signed-off-by: Alan Tull <redacted>
Signed-off-by: Dinh Nguyen <redacted>
Signed-off-by: Matthew Gerlach <redacted>
---
v2:  separate into 2 documents for the 2 drivers
v12: bump version to line up with simple-fpga-bus version
     remove Linux specific notes such as references to sysfs
     move non-DT specific documentation elsewhere
     remove bindings that would have been used to pass configuration
     clean up formatting
---
 .../bindings/fpga/altera-fpga2sdram-bridge.txt     |   18 ++++++++++
 .../bindings/fpga/altera-hps2fpga-bridge.txt       |   36 ++++++++++++++++++++
 2 files changed, 54 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/fpga/altera-fpga2sdram-bridge.txt
 create mode 100644 Documentation/devicetree/bindings/fpga/altera-hps2fpga-bridge.txt

diff --git a/Documentation/devicetree/bindings/fpga/altera-fpga2sdram-bridge.txt b/Documentation/devicetree/bindings/fpga/altera-fpga2sdram-bridge.txt
new file mode 100644
index 0000000..11eb5b7
--- /dev/null
+++ b/Documentation/devicetree/bindings/fpga/altera-fpga2sdram-bridge.txt

@@ -0,0 +1,18 @@
+Altera FPGA To SDRAM Bridge Driver
+
+Required properties:
+- compatible		: Should contain "altr,socfpga-fpga2sdram-bridge"
+
+Optional properties:
+- label			: User-readable name for this bridge.
+			  Default is br<device#>
+- init-val		: 0 if driver should disable bridge at startup
+			  1 if driver should enable bridge at startup
+			  Default is to leave bridge in current state.

+
+Example:
+	fpga2sdram_br: fpgabridge@3 {
+		compatible = "altr,socfpga-fpga2sdram-bridge";
+		label = "fpga2sdram";
+		init-val = <0>;
+	};

diff --git a/Documentation/devicetree/bindings/fpga/altera-hps2fpga-bridge.txt b/Documentation/devicetree/bindings/fpga/altera-hps2fpga-bridge.txt
new file mode 100644
index 0000000..eb52f3b
--- /dev/null
+++ b/Documentation/devicetree/bindings/fpga/altera-hps2fpga-bridge.txt

@@ -0,0 +1,36 @@
+Altera FPGA/HPS Bridge Driver
+
+Required properties:
+- compatible	: Should contain one of:
+		  "altr,socfpga-hps2fpga-bridge",
+		  "altr,socfpga-lwhps2fpga-bridge", or
+		  "altr,socfpga-fpga2hps-bridge"
+- clocks	: Clocks used by this module.
+
+Optional properties:
+- label		: User-readable name for this bridge.
+		  Default is br<device#>
+- init-val	: 0 if driver should disable bridge at startup.
+		  1 if driver should enable bridge at startup.
+		  Default is to leave bridge in its current state.
+
+Example:
+	hps_fpgabridge0: fpgabridge@0 {
+		compatible = "altr,socfpga-hps2fpga-bridge";
+		label = "hps2fpga";
+		clocks = <&l4_main_clk>;
+		init-val = <1>;
+	};
+
+	hps_fpgabridge1: fpgabridge@1 {
+		compatible = "altr,socfpga-lwhps2fpga-bridge";
+		label = "lwhps2fpga";
+		clocks = <&l4_main_clk>;
+		init-val = <0>;
+	};
+
+	hps_fpgabridge2: fpgabridge@2 {
+		compatible = "altr,socfpga-fpga2hps-bridge";
+		label = "fpga2hps";
+		clocks = <&l4_main_clk>;
+	};