dt-bindings: Add devicetree bindings

Add snapshot of device tree bindings from keystone common kernel, branch
"android-mainline-keystone-qcom-release" at c4c12103f9c0 ("Snap for 9228065
from e32903b9a63bb558df8b803b076619c53c16baad to
android-mainline-keystone-qcom-release").

Change-Id: I7682079615cbd9f29340a5c1f2a1d84ec441a1f1
Signed-off-by: Melody Olvera <quic_molvera@quicinc.com>

bindings/arm/syna.txt

@@ -0,0 +1,101 @@
+Synaptics SoC Device Tree Bindings
+
+According to https://www.synaptics.com/company/news/conexant-marvell
+Synaptics has acquired the Multimedia Solutions Business of Marvell, so
+berlin SoCs are now Synaptics' SoCs now.
+
+---------------------------------------------------------------
+
+Work in progress statement:
+
+Device tree files and bindings applying to Marvell Berlin SoCs and boards are
+considered "unstable". Any Marvell Berlin device tree binding may change at any
+time. Be sure to use a device tree binary and a kernel image generated from the
+same source tree.
+
+Please refer to Documentation/devicetree/bindings/ABI.rst for a definition of a
+stable binding/ABI.
+
+---------------------------------------------------------------
+
+Boards with a SoC of the Marvell Berlin family, e.g. Armada 1500
+shall have the following properties:
+
+* Required root node properties:
+compatible: must contain "marvell,berlin"
+
+In addition, the above compatible shall be extended with the specific
+SoC and board used. Currently known SoC compatibles are:
+    "marvell,berlin2"      for Marvell Armada 1500 (BG2, 88DE3100),
+    "marvell,berlin2cd"    for Marvell Armada 1500-mini (BG2CD, 88DE3005)
+    "marvell,berlin2ct"    for Marvell Armada ? (BG2CT, 88DE????)
+    "marvell,berlin2q"     for Marvell Armada 1500-pro (BG2Q, 88DE3114)
+    "marvell,berlin3"      for Marvell Armada ? (BG3, 88DE????)
+
+* Example:
+
+/ {
+	model = "Sony NSZ-GS7";
+	compatible = "sony,nsz-gs7", "marvell,berlin2", "marvell,berlin";
+
+	...
+}
+
+* Marvell Berlin CPU control bindings
+
+CPU control register allows various operations on CPUs, like resetting them
+independently.
+
+Required properties:
+- compatible: should be "marvell,berlin-cpu-ctrl"
+- reg: address and length of the register set
+
+Example:
+
+cpu-ctrl@f7dd0000 {
+	compatible = "marvell,berlin-cpu-ctrl";
+	reg = <0xf7dd0000 0x10000>;
+};
+
+* Marvell Berlin2 chip control binding
+
+Marvell Berlin SoCs have a chip control register set providing several
+individual registers dealing with pinmux, padmux, clock, reset, and secondary
+CPU boot address. Unfortunately, the individual registers are spread among the
+chip control registers, so there should be a single DT node only providing the
+different functions which are described below.
+
+Required properties:
+- compatible:
+	* the first and second values must be:
+		"simple-mfd", "syscon"
+- reg: address and length of following register sets for
+  BG2/BG2CD: chip control register set
+  BG2Q: chip control register set and cpu pll registers
+
+* Marvell Berlin2 system control binding
+
+Marvell Berlin SoCs have a system control register set providing several
+individual registers dealing with pinmux, padmux, and reset.
+
+Required properties:
+- compatible:
+	* the first and second values must be:
+		"simple-mfd", "syscon"
+- reg: address and length of the system control register set
+
+Example:
+
+chip: chip-control@ea0000 {
+	compatible = "simple-mfd", "syscon";
+	reg = <0xea0000 0x400>;
+
+	/* sub-device nodes */
+};
+
+sysctrl: system-controller@d000 {
+	compatible = "simple-mfd", "syscon";
+	reg = <0xd000 0x100>;
+
+	/* sub-device nodes */
+};