[PATCH 1/2] dt-bindings: Add syscon-names support

[Orson Zhai <orson.zhai@unisoc.com>]

Make life easier when syscon consumer want to access multiple syscon
nodes.
Add syscon-names and relative properties to help manage complicated
cases when accessing more one syscon node.

Signed-off-by: Orson Zhai <orson.zhai@unisoc.com>
---
 .../devicetree/bindings/mfd/syscon.txt        | 36 +++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/Documentation/devicetree/bindings/mfd/syscon.txt b/Documentation/devicetree/bindings/mfd/syscon.txt
index 25d9e9c2fd53..ca7bc7608c15 100644
--- a/Documentation/devicetree/bindings/mfd/syscon.txt
+++ b/Documentation/devicetree/bindings/mfd/syscon.txt
@@ -17,6 +17,8 @@ Optional property:
 - reg-io-width: the size (in bytes) of the IO accesses that should be
   performed on the device.
 - hwlocks: reference to a phandle of a hardware spinlock provider node.
+- #syscon-cells: represents the number of args. Used when syscon-names
+  is going to be used. The value is vendor specific.
 
 Examples:
 gpr: iomuxc-gpr@20e0000 {
@@ -30,3 +32,37 @@ hwlock1: hwspinlock@40500000 {
 	reg = <0x40500000 0x1000>;
 	#hwlock-cells = <1>;
 };
+
+
+==Syscon names==
+
+Refer to syscon node by names with phandle args in syscon consumer node.
+
+Required properties:
+- syscons:	List of phandle and any number of args. Args is specific to
+		differnet vendor. For example: In Unisoc SoCs, the 1st arg
+		will be treated as register address offset and the 2nd is bit
+		mask as default.
+
+- syscon-names:	List of syscon node name strings sorted in the same
+		order as the syscons property.
+
+Examples:
+
+apb_regs: syscon@20008000 {
+	compatible = "sprd,apb-glb", "syscon";
+	#syscon-cells = <2>;
+	reg = <0x20008000 0x100>;
+};
+
+aon_regs: syscon@40008000 {
+	compatible = "sprd,aon-glb", "syscon";
+	#syscon-cells = <1>;
+	reg = <0x40008000 0x100>;
+};
+
+display@40500000 {
+	...
+	syscons = <&ap_apb_regs 0x4 0xf00>, <&aon_regs 0x8>;
+	syscon-names = "enable", "power";
+};
-- 
2.18.0