dt-bindings: phy: Add support for QMP phy

Qualcomm chipsets have QMP phy controller that provides
support to a number of controller, viz. PCIe, UFS, and USB.
Adding dt binding information for the same.
Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>

Documentation/devicetree/bindings/phy/qcom-qmp-phy.txt

+Qualcomm QMP PHY controller
+===========================
+
+QMP phy controller supports physical layer functionality for a number of
+controllers on Qualcomm chipsets, such as, PCIe, UFS, and USB.
+
+Required properties:
+ - compatible: compatible list, contains:
+	       "qcom,msm8996-qmp-pcie-phy" for 14nm PCIe phy on msm8996,
+	       "qcom,msm8996-qmp-usb3-phy" for 14nm USB3 phy on msm8996.
+
+ - reg: offset and length of register set for PHY's common serdes block.
+
+ - #clock-cells: must be 1
+    - Phy pll outputs a bunch of clocks for Tx, Rx and Pipe
+      interface (for pipe based PHYs). These clock are then gate-controlled
+      by gcc.
+ - #address-cells: must be 1
+ - #size-cells: must be 1
+ - ranges: must be present
+
+ - clocks: a list of phandles and clock-specifier pairs,
+	   one for each entry in clock-names.
+ - clock-names: "cfg_ahb" for phy config clock,
+		"aux" for phy aux clock,
+		"ref" for 19.2 MHz ref clk,
+		For "qcom,msm8996-qmp-pcie-phy" must contain:
+			"aux", "cfg_ahb", "ref".
+		For "qcom,msm8996-qmp-usb3-phy" must contain:
+			"aux", "cfg_ahb", "ref".
+
+ - resets: a list of phandles and reset controller specifier pairs,
+	   one for each entry in reset-names.
+ - reset-names: "phy" for reset of phy block,
+		"common" for phy common block reset,
+		"cfg" for phy's ahb cfg block reset (Optional).
+		For "qcom,msm8996-qmp-pcie-phy" must contain:
+		 "phy", "common", "cfg".
+		For "qcom,msm8996-qmp-usb3-phy" must contain
+		 "phy", "common".
+
+ - vdda-phy-supply: Phandle to a regulator supply to PHY core block.
+ - vdda-pll-supply: Phandle to 1.8V regulator supply to PHY refclk pll block.
+
+Optional properties:
+ - vddp-ref-clk-supply: Phandle to a regulator supply to any specific refclk
+			pll block.
+
+Required nodes:
+ - Each device node of QMP phy is required to have as many child nodes as
+   the number of lanes the PHY has.
+
+Required properties for child node:
+ - reg: list of offset and length pairs of register sets for PHY blocks -
+	tx, rx and pcs.
+
+ - #phy-cells: must be 0
+
+ - clocks: a list of phandles and clock-specifier pairs,
+	   one for each entry in clock-names.
+ - clock-names: Must contain following for pcie and usb qmp phys:
+		 "pipe<lane-number>" for pipe clock specific to each lane.
+
+ - resets: a list of phandles and reset controller specifier pairs,
+	   one for each entry in reset-names.
+ - reset-names: Must contain following for pcie qmp phys:
+		 "lane<lane-number>" for reset specific to each lane.
+
+Example:
+	phy@34000 {
+		compatible = "qcom,msm8996-qmp-pcie-phy";
+		reg = <0x34000 0x488>;
+		#clock-cells = <1>;
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges;
+
+		clocks = <&gcc GCC_PCIE_PHY_AUX_CLK>,
+			<&gcc GCC_PCIE_PHY_CFG_AHB_CLK>,
+			<&gcc GCC_PCIE_CLKREF_CLK>;
+		clock-names = "aux", "cfg_ahb", "ref";
+
+		vdda-phy-supply = <&pm8994_l28>;
+		vdda-pll-supply = <&pm8994_l12>;
+
+		resets = <&gcc GCC_PCIE_PHY_BCR>,
+			<&gcc GCC_PCIE_PHY_COM_BCR>,
+			<&gcc GCC_PCIE_PHY_COM_NOCSR_BCR>;
+		reset-names = "phy", "common", "cfg";
+
+		pciephy_0: lane@35000 {
+			reg = <0x35000 0x130>,
+				<0x35200 0x200>,
+				<0x35400 0x1dc>;
+			#phy-cells = <0>;
+
+			clocks = <&gcc GCC_PCIE_0_PIPE_CLK>;
+			clock-names = "pipe0";
+			resets = <&gcc GCC_PCIE_0_PHY_BCR>;
+			reset-names = "lane0";
+		};
+
+		pciephy_1: lane@36000 {
+		...
+		...
+	};