[PATCH v15 3/6] ARM: socfpga: add bindings document for fpga bridge drivers

[<atull@opensource.altera.com>]

From: Alan Tull <atull@opensource.altera.com>

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

Signed-off-by: Alan Tull <atull@opensource.altera.com>
Signed-off-by: Matthew Gerlach <mgerlach@altera.com>
Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
---
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
v13: Remove 'label' property
     Change property from init-val to bridge-enable
     Fix email address
v14: Add resets
     Change order of bridges to put lw bridge (controlling bridge) first
v15: No change in this patch for v15 of this patch set
---
 .../bindings/fpga/altera-fpga2sdram-bridge.txt     |   15 +++++++
 .../bindings/fpga/altera-hps2fpga-bridge.txt       |   43 ++++++++++++++++++++
 2 files changed, 58 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..81e2f06
--- /dev/null
+++ b/Documentation/devicetree/bindings/fpga/altera-fpga2sdram-bridge.txt
@@ -0,0 +1,15 @@
+Altera FPGA To SDRAM Bridge Driver
+
+Required properties:
+- compatible		: Should contain "altr,socfpga-fpga2sdram-bridge"
+
+Optional properties:
+- bridge-enable		: 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";
+		bridge-enable = <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..16db3b0
--- /dev/null
+++ b/Documentation/devicetree/bindings/fpga/altera-hps2fpga-bridge.txt
@@ -0,0 +1,43 @@
+Altera FPGA/HPS Bridge Driver
+
+Required properties:
+- compatible	: Should contain one of:
+		  "altr,socfpga-lwhps2fpga-bridge",
+		  "altr,socfpga-hps2fpga-bridge", or
+		  "altr,socfpga-fpga2hps-bridge"
+- reset-names	: Should contain one of:
+		  "lwhps2fpga",
+		  "hps2fpga", or
+		  "fpga2hps"
+- resets	: Phandle and reset specifier for the reset listed in
+		  reset-names
+- clocks	: Clocks used by this module.
+
+Optional properties:
+- bridge-enable	: 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-lwhps2fpga-bridge";
+		resets = <&rst LWHPS2FPGA_RESET>;
+		reset-names = "lwhps2fpga";
+		clocks = <&l4_main_clk>;
+		bridge-enable = <0>;
+	};
+
+	hps_fpgabridge1: fpgabridge@1 {
+		compatible = "altr,socfpga-hps2fpga-bridge";
+		resets = <&rst HPS2FPGA_RESET>;
+		reset-names = "hps2fpga";
+		clocks = <&l4_main_clk>;
+		bridge-enable = <1>;
+	};
+
+	hps_fpgabridge2: fpgabridge@2 {
+		compatible = "altr,socfpga-fpga2hps-bridge";
+		resets = <&rst FPGA2HPS_RESET>;
+		reset-names = "fpga2hps";
+		clocks = <&l4_main_clk>;
+	};
-- 
1.7.9.5