--- /dev/null
+.. SPDX-License-Identifier: GPL-2.0
+
+=====================================
+Devicetree Sources (DTS) Coding Style
+=====================================
+
+When writing Devicetree Sources (DTS) please observe below guidelines. They
+should be considered complementary to any rules expressed already in
+the Devicetree Specification and the dtc compiler (including W=1 and W=2
+builds).
+
+Individual architectures and subarchitectures can define additional rules,
+making the coding style stricter.
+
+Naming and Valid Characters
+---------------------------
+
+The Devicetree Specification allows a broad range of characters in node
+and property names, but this coding style narrows the range down to achieve
+better code readability.
+
+1. Node and property names can use only the following characters:
+
+ * Lowercase characters: [a-z]
+ * Digits: [0-9]
+ * Dash: -
+
+2. Labels can use only the following characters:
+
+ * Lowercase characters: [a-z]
+ * Digits: [0-9]
+ * Underscore: _
+
+3. Unless a bus defines differently, unit addresses shall use lowercase
+ hexadecimal digits, without leading zeros (padding).
+
+4. Hex values in properties, e.g. "reg", shall use lowercase hex. The address
+ part can be padded with leading zeros.
+
+Example::
+
+ gpi_dma2: dma-controller@a00000 {
+ compatible = "qcom,sm8550-gpi-dma", "qcom,sm6350-gpi-dma";
+ reg = <0x0 0x00a00000 0x0 0x60000>;
+ }
+
+Order of Nodes
+--------------
+
+1. Nodes on any bus, thus using unit addresses for children, shall be
+ ordered by unit address in ascending order.
+ Alternatively for some subarchitectures, nodes of the same type can be
+ grouped together, e.g. all I2C controllers one after another even if this
+ breaks unit address ordering.
+
+2. Nodes without unit addresses shall be ordered alpha-numerically by the node
+ name. For a few node types, they can be ordered by the main property, e.g.
+ pin configuration states ordered by value of "pins" property.
+
+3. When extending nodes in the board DTS via &label, the entries shall be
+ ordered either alpha-numerically or by keeping the order from DTSI, where
+ the choice depends on the subarchitecture.
+
+The above-described ordering rules are easy to enforce during review, reduce
+chances of conflicts for simultaneous additions of new nodes to a file and help
+in navigating through the DTS source.
+
+Example::
+
+ /* SoC DTSI */
+
+ / {
+ cpus {
+ /* ... */
+ };
+
+ psci {
+ /* ... */
+ };
+
+ soc@0 {
+ dma: dma-controller@10000 {
+ /* ... */
+ };
+
+ clk: clock-controller@80000 {
+ /* ... */
+ };
+ };
+ };
+
+ /* Board DTS - alphabetical order */
+
+ &clk {
+ /* ... */
+ };
+
+ &dma {
+ /* ... */
+ };
+
+ /* Board DTS - alternative order, keep as DTSI */
+
+ &dma {
+ /* ... */
+ };
+
+ &clk {
+ /* ... */
+ };
+
+Order of Properties in Device Node
+----------------------------------
+
+The following order of properties in device nodes is preferred:
+
+1. "compatible"
+2. "reg"
+3. "ranges"
+4. Standard/common properties (defined by common bindings, e.g. without
+ vendor-prefixes)
+5. Vendor-specific properties
+6. "status" (if applicable)
+7. Child nodes, where each node is preceded with a blank line
+
+The "status" property is by default "okay", thus it can be omitted.
+
+The above-described ordering follows this approach:
+
+1. Most important properties start the node: compatible then bus addressing to
+ match unit address.
+2. Each node will have common properties in similar place.
+3. Status is the last information to annotate that device node is or is not
+ finished (board resources are needed).
+
+Example::
+
+ /* SoC DTSI */
+
+ device_node: device-class@6789abc {
+ compatible = "vendor,device";
+ reg = <0x0 0x06789abc 0x0 0xa123>;
+ ranges = <0x0 0x0 0x06789abc 0x1000>;
+ #dma-cells = <1>;
+ clocks = <&clock_controller 0>, <&clock_controller 1>;
+ clock-names = "bus", "host";
+ vendor,custom-property = <2>;
+ status = "disabled";
+
+ child_node: child-class@100 {
+ reg = <0x100 0x200>;
+ /* ... */
+ };
+ };
+
+ /* Board DTS */
+
+ &device_node {
+ vdd-supply = <&board_vreg1>;
+ status = "okay";
+ }
+
+Indentation
+-----------
+
+1. Use indentation according to Documentation/process/coding-style.rst.
+2. Each entry in arrays with multiple cells, e.g. "reg" with two IO addresses,
+ shall be enclosed in <>.
+3. For arrays spanning across lines, it is preferred to align the continued
+ entries with opening < from the first line.
+
+Example::
+
+ thermal-sensor@c271000 {
+ compatible = "qcom,sm8550-tsens", "qcom,tsens-v2";
+ reg = <0x0 0x0c271000 0x0 0x1000>,
+ <0x0 0x0c222000 0x0 0x1000>;
+ };
+
+Organizing DTSI and DTS
+-----------------------
+
+The DTSI and DTS files shall be organized in a way representing the common,
+reusable parts of hardware. Typically, this means organizing DTSI and DTS files
+into several files:
+
+1. DTSI with contents of the entire SoC, without nodes for hardware not present
+ on the SoC.
+2. If applicable: DTSI with common or re-usable parts of the hardware, e.g.
+ entire System-on-Module.
+3. DTS representing the board.
+
+Hardware components that are present on the board shall be placed in the
+board DTS, not in the SoC or SoM DTSI. A partial exception is a common
+external reference SoC input clock, which could be coded as a fixed-clock in
+the SoC DTSI with its frequency provided by each board DTS.
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