powerpc/mpc5xxx: add OF platform binding doc for FSL MSCAN devices

This patch adds documentation for the MSCAN OF device bindings for
the MPC512x and moves the one for the MPC5200 to the new common file
"Documentation/powerpc/dts-bindings/fsl/can.txt".
Signed-off-by: Wolfgang Grandegger <wg@denx.de>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/powerpc/dts-bindings/fsl/can.txt

+CAN Device Tree Bindings
+------------------------
+
+(c) 2006-2009 Secret Lab Technologies Ltd
+Grant Likely <grant.likely@secretlab.ca>
+
+fsl,mpc5200-mscan nodes
+-----------------------
+In addition to the required compatible-, reg- and interrupt-properties, you can
+also specify which clock source shall be used for the controller:
+
+- fsl,mscan-clock-source : a string describing the clock source. Valid values
+			   are:	"ip" for ip bus clock
+				 "ref" for reference clock (XTAL)
+			   "ref" is default in case this property is not
+			   present.
+
+fsl,mpc5121-mscan nodes
+-----------------------
+In addition to the required compatible-, reg- and interrupt-properties, you can
+also specify which clock source and divider shall be used for the controller:
+
+- fsl,mscan-clock-source : a string describing the clock source. Valid values
+			   are:	"ip" for ip bus clock
+				"ref" for reference clock
+				"sys" for system clock
+			   If this property is not present, an optimal CAN
+			   clock source and frequency based on the system
+			   clock will be selected. If this is not possible,
+			   the reference clock will be used.
+
+- fsl,mscan-clock-divider: for the reference and system clock, an additional
+			   clock divider can be specified. By default, a
+			   value of 1 is used.
+
+Note that the MPC5121 Rev. 1 processor is not supported.
+
+Examples:
+	can@1300 {
+		compatible = "fsl,mpc5121-mscan";
+		interrupts = <12 0x8>;
+		interrupt-parent = <&ipic>;
+		reg = <0x1300 0x80>;
+	};
+
+	can@1380 {
+		compatible = "fsl,mpc5121-mscan";
+		interrupts = <13 0x8>;
+		interrupt-parent = <&ipic>;
+		reg = <0x1380 0x80>;
+		fsl,mscan-clock-source = "ref";
+		fsl,mscan-clock-divider = <3>;
+	};

Documentation/powerpc/dts-bindings/fsl/mpc5200.txt

@@ -195,11 +195,4 @@ External interrupts:
 
 fsl,mpc5200-mscan nodes
 -----------------------
-In addition to the required compatible-, reg- and interrupt-properites, you can
-also specify which clock source shall be used for the controller:
-
-- fsl,mscan-clock-source- a string describing the clock source. Valid values
-			  are:	"ip" for ip bus clock
-				"ref" for reference clock (XTAL)
-			  "ref" is default in case this property is not
-			  present.
+See file can.txt in this directory.