dt-bindings: reset: Add AOSS reset bindings for SDM845 SoCs

Add SDM845 AOSS (always on subsystem) reset controller binding
Signed-off-by: NSibi Sankar <sibis@codeaurora.org>
Reviewed-by: NBjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: NRob Herring <robh@kernel.org>
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>

Documentation/devicetree/bindings/reset/qcom,aoss-reset.txt

+Qualcomm AOSS Reset Controller
+======================================
+
+This binding describes a reset-controller found on AOSS-CC (always on subsystem)
+for Qualcomm SDM845 SoCs.
+
+Required properties:
+- compatible:
+	Usage: required
+	Value type: <string>
+	Definition: must be:
+		    "qcom,sdm845-aoss-cc"
+
+- reg:
+	Usage: required
+	Value type: <prop-encoded-array>
+	Definition: must specify the base address and size of the register
+	            space.
+
+- #reset-cells:
+	Usage: required
+	Value type: <uint>
+	Definition: must be 1; cell entry represents the reset index.
+
+Example:
+
+aoss_reset: reset-controller@c2a0000 {
+	compatible = "qcom,sdm845-aoss-cc";
+	reg = <0xc2a0000 0x31000>;
+	#reset-cells = <1>;
+};
+
+Specifying reset lines connected to IP modules
+==============================================
+
+Device nodes that need access to reset lines should
+specify them as a reset phandle in their corresponding node as
+specified in reset.txt.
+
+For list of all valid reset indicies see
+<dt-bindings/reset/qcom,sdm845-aoss.h>
+
+Example:
+
+modem-pil@4080000 {
+	...
+
+	resets = <&aoss_reset AOSS_CC_MSS_RESTART>;
+	reset-names = "mss_restart";
+
+	...
+};

include/dt-bindings/reset/qcom,sdm845-aoss.h

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2018 The Linux Foundation. All rights reserved.
+ */
+
+#ifndef _DT_BINDINGS_RESET_AOSS_SDM_845_H
+#define _DT_BINDINGS_RESET_AOSS_SDM_845_H
+
+#define AOSS_CC_MSS_RESTART	0
+#define AOSS_CC_CAMSS_RESTART	1
+#define AOSS_CC_VENUS_RESTART	2
+#define AOSS_CC_GPU_RESTART	3
+#define AOSS_CC_DISPSS_RESTART	4
+#define AOSS_CC_WCSS_RESTART	5
+#define AOSS_CC_LPASS_RESTART	6
+
+#endif