soc: qcom: Add device tree binding for GSBI

Add device tree binding support for the QCOM GSBI driver.
Signed-off-by: Andy Gross <agross@codeaurora.org>
Signed-off-by: Kumar Gala <galak@codeaurora.org>

Documentation/devicetree/bindings/soc/qcom/qcom,gsbi.txt

+QCOM GSBI (General Serial Bus Interface) Driver
+
+The GSBI controller is modeled as a node with zero or more child nodes, each
+representing a serial sub-node device that is mux'd as part of the GSBI
+configuration settings.  The mode setting will govern the input/output mode of
+the 4 GSBI IOs.
+
+Required properties:
+- compatible: must contain "qcom,gsbi-v1.0.0" for APQ8064/IPQ8064
+- reg: Address range for GSBI registers
+- clocks: required clock
+- clock-names: must contain "iface" entry
+- qcom,mode : indicates MUX value for configuration of the serial interface.
+  Please reference dt-bindings/soc/qcom,gsbi.h for valid mux values.
+
+Optional properties:
+- qcom,crci : indicates CRCI MUX value for QUP CRCI ports.  Please reference
+  dt-bindings/soc/qcom,gsbi.h for valid CRCI mux values.
+
+Required properties if child node exists:
+- #address-cells: Must be 1
+- #size-cells: Must be 1
+- ranges: Must be present
+
+Properties for children:
+
+A GSBI controller node can contain 0 or more child nodes representing serial
+devices.  These serial devices can be a QCOM UART, I2C controller, spi
+controller, or some combination of aforementioned devices.
+
+See the following for child node definitions:
+Documentation/devicetree/bindings/i2c/qcom,i2c-qup.txt
+Documentation/devicetree/bindings/spi/qcom,spi-qup.txt
+Documentation/devicetree/bindings/serial/qcom,msm-uartdm.txt
+
+Example for APQ8064:
+
+#include <dt-bindings/soc/qcom,gsbi.h>
+
+	gsbi4@16300000 {
+		compatible = "qcom,gsbi-v1.0.0";
+		reg = <0x16300000 0x100>;
+		clocks = <&gcc GSBI4_H_CLK>;
+		clock-names = "iface";
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges;
+		qcom,mode = <GSBI_PROT_I2C_UART>;
+		qcom,crci = <GSBI_CRCI_QUP>;
+
+		/* child nodes go under here */
+
+		i2c_qup4: i2c@16380000 {
+		        compatible = "qcom,i2c-qup-v1.1.1";
+		        reg = <0x16380000 0x1000>;
+		        interrupts = <0 153 0>;
+
+		        clocks = <&gcc GSBI4_QUP_CLK>, <&gcc GSBI4_H_CLK>;
+		        clock-names = "core", "iface";
+
+		        clock-frequency = <200000>;
+
+		        #address-cells = <1>;
+		        #size-cells = <0>;
+
+		 };
+
+		uart4:	serial@16340000 {
+			compatible = "qcom,msm-uartdm-v1.3", "qcom,msm-uartdm";
+			reg = <0x16340000 0x1000>,
+				<0x16300000 0x1000>;
+			interrupts = <0 152 0x0>;
+			clocks = <&gcc GSBI4_UART_CLK>, <&gcc GSBI4_H_CLK>;
+			clock-names = "core", "iface";
+			status = "ok";
+		};
+	};
+

include/dt-bindings/soc/qcom,gsbi.h

+/* Copyright (c) 2013, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+#ifndef __DT_BINDINGS_QCOM_GSBI_H
+#define __DT_BINDINGS_QCOM_GSBI_H
+
+#define GSBI_PROT_IDLE		0
+#define GSBI_PROT_I2C_UIM	1
+#define GSBI_PROT_I2C		2
+#define GSBI_PROT_SPI		3
+#define GSBI_PROT_UART_W_FC	4
+#define GSBI_PROT_UIM		5
+#define GSBI_PROT_I2C_UART	6
+
+#define GSBI_CRCI_QUP		0
+#define GSBI_CRCI_UART		1
+
+#endif