doc: dt: mtd: support partitions in a special 'partitions' subnode

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Gitweb:     http://git.infradead.org/?p=mtd-2.6.git;a=commit;h=fe2585e9c29a650af26824684e5033757fd6bc0c
Commit:     fe2585e9c29a650af26824684e5033757fd6bc0c
Parent:     4d1ea982a9beb4e47bba41131973329e2a012b38
Author:     Michal Suchanek <hramrach at gmail.com>
AuthorDate: Wed Oct 28 15:48:06 2015 -0700
Committer:  Brian Norris <computersforpeace at gmail.com>
CommitDate: Fri Oct 30 14:00:42 2015 -0700

    doc: dt: mtd: support partitions in a special 'partitions' subnode
    
    To avoid conflict with other drivers using subnodes of the mtd device
    create only one ofpart-specific node rather than any number of
    arbitrary partition subnodes.
    
    Signed-off-by: Michal Suchanek <hramrach at gmail.com>
    Acked-by: Rob Herring <robh at kernel.org>
    Signed-off-by: Brian Norris <computersforpeace at gmail.com>
---
 .../devicetree/bindings/mtd/partition.txt          | 71 +++++++++++++---------
 1 file changed, 42 insertions(+), 29 deletions(-)

diff --git a/Documentation/devicetree/bindings/mtd/partition.txt b/Documentation/devicetree/bindings/mtd/partition.txt
index 8e5557d..f1e2a02 100644
--- a/Documentation/devicetree/bindings/mtd/partition.txt
+++ b/Documentation/devicetree/bindings/mtd/partition.txt
@@ -4,10 +4,17 @@ Partitions can be represented by sub-nodes of an mtd device. This can be used
 on platforms which have strong conventions about which portions of a flash are
 used for what purposes, but which don't use an on-flash partition table such
 as RedBoot.
-NOTE: if the sub-node has a compatible string, then it is not a partition.
 
-#address-cells & #size-cells must both be present in the mtd device. There are
-two valid values for both:
+The partition table should be a subnode of the mtd node and should be named
+'partitions'. Partitions are defined in subnodes of the partitions node.
+
+For backwards compatibility partitions as direct subnodes of the mtd device are
+supported. This use is discouraged.
+NOTE: also for backwards compatibility, direct subnodes that have a compatible
+string are not considered partitions, as they may be used for other bindings.
+
+#address-cells & #size-cells must both be present in the partitions subnode of the
+mtd device. There are two valid values for both:
 <1>: for partitions that require a single 32-bit cell to represent their
      size/address (aka the value is below 4 GiB)
 <2>: for partitions that require two 32-bit cells to represent their
@@ -28,44 +35,50 @@ Examples:
 
 
 flash at 0 {
-	#address-cells = <1>;
-	#size-cells = <1>;
+	partitions {
+		#address-cells = <1>;
+		#size-cells = <1>;
 
-	partition at 0 {
-		label = "u-boot";
-		reg = <0x0000000 0x100000>;
-		read-only;
-	};
+		partition at 0 {
+			label = "u-boot";
+			reg = <0x0000000 0x100000>;
+			read-only;
+		};
 
-	uimage at 100000 {
-		reg = <0x0100000 0x200000>;
+		uimage at 100000 {
+			reg = <0x0100000 0x200000>;
+		};
 	};
 };
 
 flash at 1 {
-	#address-cells = <1>;
-	#size-cells = <2>;
+	partitions {
+		#address-cells = <1>;
+		#size-cells = <2>;
 
-	/* a 4 GiB partition */
-	partition at 0 {
-		label = "filesystem";
-		reg = <0x00000000 0x1 0x00000000>;
+		/* a 4 GiB partition */
+		partition at 0 {
+			label = "filesystem";
+			reg = <0x00000000 0x1 0x00000000>;
+		};
 	};
 };
 
 flash at 2 {
-	#address-cells = <2>;
-	#size-cells = <2>;
+	partitions {
+		#address-cells = <2>;
+		#size-cells = <2>;
 
-	/* an 8 GiB partition */
-	partition at 0 {
-		label = "filesystem #1";
-		reg = <0x0 0x00000000 0x2 0x00000000>;
-	};
+		/* an 8 GiB partition */
+		partition at 0 {
+			label = "filesystem #1";
+			reg = <0x0 0x00000000 0x2 0x00000000>;
+		};
 
-	/* a 4 GiB partition */
-	partition at 200000000 {
-		label = "filesystem #2";
-		reg = <0x2 0x00000000 0x1 0x00000000>;
+		/* a 4 GiB partition */
+		partition at 200000000 {
+			label = "filesystem #2";
+			reg = <0x2 0x00000000 0x1 0x00000000>;
+		};
 	};
 };