[PATCH v5 4/7] dtc: dt-check-style: Expect first device_type
From: Krzysztof Kozlowski
Date: Thu Jul 09 2026 - 13:45:31 EST
A few nodes do have "device_type" property which is mostly, but not always,
the first property in a device node, when applicable. Adjust the DTS
coding style rules to actually expect the device_type first and improve
the dt-check-style to handle this correctly.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxxxxx>
---
Changes in v3:
New patch
---
.../devicetree/bindings/dts-coding-style.rst | 15 ++++----
scripts/dtc/dt-check-style | 33 +++++++++--------
.../dt-style-selftest/bad/dts-property-order.dts | 43 ++++++++++++++++++++++
.../bad/yaml-prop-order-device-type.yaml | 31 ++++++++++++++++
.../expected/dts-property-order.dts.txt | 6 +++
.../expected/yaml-prop-order-device-type.yaml.txt | 2 +
.../dt-style-selftest/good/dts-property-order.dts | 41 +++++++++++++++++++++
7 files changed, 149 insertions(+), 22 deletions(-)
diff --git a/Documentation/devicetree/bindings/dts-coding-style.rst b/Documentation/devicetree/bindings/dts-coding-style.rst
index 4a02ea60cbbe..63648db377e1 100644
--- a/Documentation/devicetree/bindings/dts-coding-style.rst
+++ b/Documentation/devicetree/bindings/dts-coding-style.rst
@@ -114,15 +114,16 @@ 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
+1. "device_type" (if applicable)
+2. "compatible"
+3. "reg"
+4. "ranges"
+5. Standard/common properties (defined by common bindings, e.g. without
vendor-prefixes)
-5. Vendor-specific properties
-6. "status" (if applicable), preceded by a blank line if there is content
+6. Vendor-specific properties
+7. "status" (if applicable), preceded by a blank line if there is content
before the property
-7. Child nodes, where each node is preceded with a blank line
+8. Child nodes, where each node is preceded with a blank line
The "status" property is by default "okay", thus it can be omitted.
diff --git a/scripts/dtc/dt-check-style b/scripts/dtc/dt-check-style
index f5276b5fdd46..d19ef26c2213 100755
--- a/scripts/dtc/dt-check-style
+++ b/scripts/dtc/dt-check-style
@@ -565,28 +565,31 @@ def check_child_name_order(ctx):
def _property_bucket(name):
"""Return the canonical bucket index for a property:
- 0 compatible
- 1 reg / reg-names
- 2 ranges
- 3 standard properties (no vendor comma in #-stripped name)
- 4 vendor-specific properties
- 5 status
- Plus a sub-key inside the bucket for fixed slots (compatible, reg,
- reg-names, ranges, status). 'standard' and 'vendor' return None for
+ 0 device_type
+ 1 compatible
+ 2 reg / reg-names
+ 3 ranges
+ 4 standard properties (no vendor comma in #-stripped name)
+ 5 vendor-specific properties
+ 6 status
+ Plus a sub-key inside the bucket for fixed slots (device_type, compatible,
+ reg, reg-names, ranges, status). 'standard' and 'vendor' return None for
the sub-key, signalling that the within-bucket key is computed by
the pairing rules."""
stripped = name.lstrip('#')
- if name == 'compatible':
+ if name == 'device_type':
return (0, 0)
- if name == 'reg':
+ if name == 'compatible':
return (1, 0)
- if name == 'reg-names':
- return (1, 1)
- if name == 'ranges':
+ if name == 'reg':
return (2, 0)
+ if name == 'reg-names':
+ return (2, 1)
+ if name == 'ranges':
+ return (3, 0)
if name == 'status':
- return (5, 0)
- return (4 if ',' in stripped else 3, None)
+ return (6, 0)
+ return (5 if ',' in stripped else 4, None)
# Declarative pairing rules: each is a callable
diff --git a/scripts/dtc/dt-style-selftest/bad/dts-property-order.dts b/scripts/dtc/dt-style-selftest/bad/dts-property-order.dts
new file mode 100644
index 000000000000..f31abb6ceae4
--- /dev/null
+++ b/scripts/dtc/dt-style-selftest/bad/dts-property-order.dts
@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+/*
+ * Test fixture: Incorrect property order
+ */
+
+/dts-v1/;
+
+/ {
+ cpus {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ cpu@0 {
+ reg = <0x0 0x0>;
+ compatible = "arm,cortex-a57";
+ device_type = "cpu";
+ enable-method = "psci";
+ };
+ };
+
+ pmu {
+ compatible = "example,pmu";
+
+ status = "disabled";
+ dma-coherent;
+ };
+
+ soc@0 {
+ ranges = <0 0 0 0xc0000000>;
+ compatible = "simple-bus";
+
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ interrupt-controller@10000 {
+ reg = <0x10000 0x1000>;
+ interrupts = <1 2 3>,
+ <4 5 6>,
+ <7 8 9>;
+ compatible = "example,intc";
+ };
+ };
+};
diff --git a/scripts/dtc/dt-style-selftest/bad/yaml-prop-order-device-type.yaml b/scripts/dtc/dt-style-selftest/bad/yaml-prop-order-device-type.yaml
new file mode 100644
index 000000000000..e2c69e9ff452
--- /dev/null
+++ b/scripts/dtc/dt-style-selftest/bad/yaml-prop-order-device-type.yaml
@@ -0,0 +1,31 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/test-bad-prop-order.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Test fixture with device_type
+
+maintainers:
+ - Test User <test@xxxxxxxxxxx>
+
+properties:
+ compatible:
+ const: example,test-prop-order-device-type
+ reg:
+ maxItems: 1
+ device_type: true
+
+required:
+ - compatible
+ - reg
+
+additionalProperties: false
+
+examples:
+ - |
+ device@1000 {
+ compatible = "example,test-prop-order-device-type";
+ device_type = "cpu";
+ reg = <0x1000 0x100>;
+ };
diff --git a/scripts/dtc/dt-style-selftest/expected/dts-property-order.dts.txt b/scripts/dtc/dt-style-selftest/expected/dts-property-order.dts.txt
new file mode 100644
index 000000000000..4bc21328625f
--- /dev/null
+++ b/scripts/dtc/dt-style-selftest/expected/dts-property-order.dts.txt
@@ -0,0 +1,6 @@
+# mode=strict
+bad/dts-property-order.dts:15: [property-order] property 'compatible' out of canonical order (should sort before 'reg')
+bad/dts-property-order.dts:16: [property-order] property 'device_type' out of canonical order (should sort before 'compatible')
+bad/dts-property-order.dts:25: [property-order] property 'dma-coherent' out of canonical order (should sort before 'status')
+bad/dts-property-order.dts:30: [property-order] property 'compatible' out of canonical order (should sort before 'ranges')
+bad/dts-property-order.dts:40: [property-order] property 'compatible' out of canonical order (should sort before 'interrupts')
diff --git a/scripts/dtc/dt-style-selftest/expected/yaml-prop-order-device-type.yaml.txt b/scripts/dtc/dt-style-selftest/expected/yaml-prop-order-device-type.yaml.txt
new file mode 100644
index 000000000000..9350e2b80f75
--- /dev/null
+++ b/scripts/dtc/dt-style-selftest/expected/yaml-prop-order-device-type.yaml.txt
@@ -0,0 +1,2 @@
+# mode=strict
+bad/yaml-prop-order-device-type.yaml:29: example 0 [property-order] property 'device_type' out of canonical order (should sort before 'compatible')
diff --git a/scripts/dtc/dt-style-selftest/good/dts-property-order.dts b/scripts/dtc/dt-style-selftest/good/dts-property-order.dts
new file mode 100644
index 000000000000..0e183e3459cd
--- /dev/null
+++ b/scripts/dtc/dt-style-selftest/good/dts-property-order.dts
@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+/*
+ * Test fixture: Incorrect property order
+ */
+
+/dts-v1/;
+
+/ {
+ cpus {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ cpu@0 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a57";
+ reg = <0x0 0x0>;
+ enable-method = "psci";
+ };
+ };
+
+ pmu {
+ compatible = "example,pmu";
+ dma-coherent;
+
+ status = "disabled";
+ };
+
+ soc@0 {
+ compatible = "simple-bus";
+ ranges = <0 0 0 0xc0000000>;
+
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ interrupt-controller@10000 {
+ compatible = "example,intc";
+ reg = <0x10000 0x1000>;
+ interrupts = <1 2 3>;
+ };
+ };
+};
--
2.53.0