dtc: dt-check-style: Add warning for redundant white-spaces

Show warnings of too many spaces around '=', after ':', before '{' and
';' characters, or using tabs for these.  Both in-tree DTS and DT
bindings have many warnings for the first case (too mant spaces around
'='), thus keep this one only for 'strict' mode.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Link: https://patch.msgid.link/20260826-n-dts-style-checker-continued-v6-9-f270b1e81f8e@oss.qualcomm.com
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>

13 files changed, 210 insertions, 0 deletions

diff --git a/scripts/dtc/dt-check-style b/scripts/dtc/dt-check-style
index 43069fc1fac9..487e76b85105 100755
--- a/scripts/dtc/dt-check-style
+++ b/scripts/dtc/dt-check-style
@@ -349,6 +349,42 @@ def check_trailing_whitespace(ctx):
             yield (dl.lineno, 'trailing whitespace')
 
 
+def _check_redundant_whitespace(dl):
+    if dl.linetype in (LineType.COMMENT, LineType.COMMENT_BODY,
+                        LineType.COMMENT_END, LineType.COMMENT_START,
+                        LineType.PREPROCESSOR):
+        return
+    if re.search(r'(\s\s+|\t)\{', dl.code):
+        yield (dl.lineno, 'extra whitespace before {')
+    if re.search(r':(\s\s+|\t)', dl.code):
+        yield (dl.lineno, 'extra whitespace after :')
+    if re.search(r'\s+;', dl.code):
+        yield (dl.lineno, 'extra whitespace before ;')
+
+
+def check_redundant_whitespace(ctx):
+    """No whitespace between brackets or other code elements.
+    See also check_value_whitespace() for more checks."""
+    for dl in ctx.lines:
+        yield from _check_redundant_whitespace(dl)
+        for cont in dl.continuations:
+            yield from _check_redundant_whitespace(cont)
+
+
+def check_redundant_whitespace_strict(ctx):
+    """No whitespace between brackets or other code elements.
+    See also check_value_whitespace() for more checks."""
+    for dl in ctx.lines:
+        if dl.linetype in (LineType.COMMENT, LineType.COMMENT_BODY,
+                           LineType.COMMENT_END, LineType.COMMENT_START,
+                           LineType.PREPROCESSOR):
+            continue
+        if re.search(r'(\s\s+|\t)=', dl.code):
+            yield (dl.lineno, 'extra whitespace before =')
+        if re.search(r'=(\s\s+|\t)', dl.code):
+            yield (dl.lineno, 'extra whitespace after =')
+
+
 def check_tab_in_yaml_example(ctx):
     """Reject literal tabs in DTS lines when input is YAML.
 
@@ -1003,6 +1039,10 @@ RULES = [
     Rule('trailing-whitespace', 'relaxed',
          'no trailing whitespace on any line',
          check_trailing_whitespace),
+    # See also check_redundant_whitespace_strict() and check_value_whitespace()
+    Rule('redundant-whitespace', 'relaxed',
+         'no redundant whitespace within code',
+         check_redundant_whitespace),
     Rule('tab-in-yaml', 'relaxed',
          'YAML (also DTS examples) may not contain tab characters',
          check_tab_in_yaml_example, applies_to=('yaml',)),
@@ -1053,6 +1093,10 @@ RULES = [
     Rule('unit-address-format', 'strict',
          'unit addresses must be lowercase hex without leading zeros',
          check_unit_address_format),
+    # See also check_redundant_whitespace() and check_value_whitespace()
+    Rule('redundant-whitespace-strict', 'strict',
+         'no redundant whitespace within code',
+         check_redundant_whitespace_strict),
     Rule('value-whitespace', 'strict',
          'no whitespace directly inside <...> brackets',
          check_value_whitespace),
diff --git a/scripts/dtc/dt-style-selftest/bad/dts-redundant-ws-strict.dts b/scripts/dtc/dt-style-selftest/bad/dts-redundant-ws-strict.dts
new file mode 100644
index 000000000000..201e3940ba1c
--- /dev/null
+++ b/scripts/dtc/dt-style-selftest/bad/dts-redundant-ws-strict.dts
@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+/dts-v1/;
+
+#define SOME_MACRO(foo)					\
+	(foo) ? <1> : <2> ;
+
+/  {
+	compatible = "example,test-board";
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	/* comments  { are okay  =  though ; */
+	soc:  soc@0  { /* comments  { are okay  =  though ; */
+		compatible = "simple-bus";  /* comments  { are okay  =  though ; */
+		ranges = <0 0 0 0xc0000000>;
+
+		#address-cells	= <1>;
+		#size-cells =	<1>;
+	} ;
+}; /* comments  { are okay  =  though ; */
+
+&soc	{
+	serial:	serial@20000  { /* comments  { are okay  =  though ; */
+		compatible  = "example,serial";
+		reg =  <0x20000 0x1000>;
+	}	;
+};
diff --git a/scripts/dtc/dt-style-selftest/bad/dts-redundant-ws.dts b/scripts/dtc/dt-style-selftest/bad/dts-redundant-ws.dts
new file mode 100644
index 000000000000..f6480ddc508a
--- /dev/null
+++ b/scripts/dtc/dt-style-selftest/bad/dts-redundant-ws.dts
@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+/dts-v1/;
+
+#define SOME_MACRO(foo)					\
+	(foo) ? <1> : <2> ;
+
+/  {
+	compatible = "example,test-board";
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	/* comments  { are okay  =  though ; */
+	soc:  soc@0  { /* comments  { are okay  =  though ; */
+		compatible = "simple-bus";  /* comments  { are okay  =  though ; */
+		ranges = <0 0 0 0xc0000000>;
+
+		#address-cells = <1>;
+		#size-cells = <1>;
+	} ;
+}; /* comments  { are okay  =  though ; */
+
+&soc	{
+	serial:	serial@20000  { /* comments  { are okay  =  though ; */
+		compatible = "example,serial";
+		reg = <0x20000 0x1000>,
+		      <0x30000 0x1000> ;
+	}	; /* comments  { are okay  =  though ; */
+};
diff --git a/scripts/dtc/dt-style-selftest/bad/dts-redundant-ws.dtso b/scripts/dtc/dt-style-selftest/bad/dts-redundant-ws.dtso
new file mode 100644
index 000000000000..01d94e14071a
--- /dev/null
+++ b/scripts/dtc/dt-style-selftest/bad/dts-redundant-ws.dtso
@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+/dts-v1/;
+/plugin/;
+
+&{/}  {
+	compatible = "example,test-board";
+	#address-cells = <1>;
+	#size-cells = <1>;
+};
diff --git a/scripts/dtc/dt-style-selftest/bad/yaml-redundant-ws-strict.yaml b/scripts/dtc/dt-style-selftest/bad/yaml-redundant-ws-strict.yaml
new file mode 100644
index 000000000000..739c44fd7217
--- /dev/null
+++ b/scripts/dtc/dt-style-selftest/bad/yaml-redundant-ws-strict.yaml
@@ -0,0 +1,31 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/yaml-redundant-ws-strict.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Test fixture with redundant whitespace
+
+maintainers:
+  - Rob Herring <robh@kernel.org>
+
+properties:
+  compatible:
+    const: example,test-redundant
+  reg:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    device@1000  {
+        compatible  = "example,test-trailing";
+        reg =  <0x1000 0x100>;
+        clocks = <&clk 0>; /* comments  { are okay  =  though ; */
+        clock-names = "bus";  /* comments  { are okay  =  though ; */
+    } ;
diff --git a/scripts/dtc/dt-style-selftest/bad/yaml-redundant-ws.yaml b/scripts/dtc/dt-style-selftest/bad/yaml-redundant-ws.yaml
new file mode 100644
index 000000000000..b2f51969b0ff
--- /dev/null
+++ b/scripts/dtc/dt-style-selftest/bad/yaml-redundant-ws.yaml
@@ -0,0 +1,35 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/yaml-redundant-ws.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Test fixture with redundant whitespace
+
+maintainers:
+  - Rob Herring <robh@kernel.org>
+
+properties:
+  compatible:
+    const: example,test-redundant
+  reg:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    device@1000  { /* comments  { are okay  =  though ; */
+        compatible = "example,test-trailing";
+        reg = <0x1000 0x100>,
+              <0x3000 0x100> ;
+    } ;
+
+    device@2000 { /* comments  { are okay  =  though ; */
+        compatible = "example,test-trailing";
+        reg = <0x2000 0x100>;
+    }; /* comments  { are okay  =  though ; */
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
index aab048a0ba3b..0ab832ccf07a 100644
--- a/scripts/dtc/dt-style-selftest/expected/dts-property-order.dts.txt
+++ b/scripts/dtc/dt-style-selftest/expected/dts-property-order.dts.txt
@@ -6,5 +6,6 @@ bad/dts-property-order.dts:21: [property-order] property 'device_type' out of ca
 bad/dts-property-order.dts:30: [property-order] property 'dma-coherent' out of canonical order (should sort before 'status')
 bad/dts-property-order.dts:35: [property-order] property 'compatible' out of canonical order (should sort before 'ranges')
 bad/dts-property-order.dts:45: [property-order] property 'compatible' out of canonical order (should sort before 'interrupts')
+bad/dts-property-order.dts:50: [redundant-whitespace] extra whitespace before {
 bad/dts-property-order.dts:52: [property-order] property 'model' out of canonical order (should sort before 'compatible')
 bad/dts-property-order.dts:57: [property-order] property 'model' out of canonical order (should sort before 'compatible')
diff --git a/scripts/dtc/dt-style-selftest/expected/dts-property-order.dtso.txt b/scripts/dtc/dt-style-selftest/expected/dts-property-order.dtso.txt
index e9b3ac985718..9f2a00916329 100644
--- a/scripts/dtc/dt-style-selftest/expected/dts-property-order.dtso.txt
+++ b/scripts/dtc/dt-style-selftest/expected/dts-property-order.dtso.txt
@@ -6,5 +6,6 @@ bad/dts-property-order.dtso:22: [property-order] property 'device_type' out of c
 bad/dts-property-order.dtso:31: [property-order] property 'dma-coherent' out of canonical order (should sort before 'status')
 bad/dts-property-order.dtso:36: [property-order] property 'compatible' out of canonical order (should sort before 'ranges')
 bad/dts-property-order.dtso:46: [property-order] property 'compatible' out of canonical order (should sort before 'interrupts')
+bad/dts-property-order.dtso:51: [redundant-whitespace] extra whitespace before {
 bad/dts-property-order.dtso:53: [property-order] property 'model' out of canonical order (should sort before 'compatible')
 bad/dts-property-order.dtso:58: [property-order] property 'model' out of canonical order (should sort before 'compatible')
diff --git a/scripts/dtc/dt-style-selftest/expected/dts-redundant-ws-strict.dts.txt b/scripts/dtc/dt-style-selftest/expected/dts-redundant-ws-strict.dts.txt
new file mode 100644
index 000000000000..ac0d57bdecdf
--- /dev/null
+++ b/scripts/dtc/dt-style-selftest/expected/dts-redundant-ws-strict.dts.txt
@@ -0,0 +1,13 @@
+# mode=strict
+bad/dts-redundant-ws-strict.dts:7: [redundant-whitespace] extra whitespace before {
+bad/dts-redundant-ws-strict.dts:13: [redundant-whitespace] extra whitespace before {
+bad/dts-redundant-ws-strict.dts:13: [redundant-whitespace] extra whitespace after :
+bad/dts-redundant-ws-strict.dts:17: [redundant-whitespace-strict] extra whitespace before =
+bad/dts-redundant-ws-strict.dts:18: [redundant-whitespace-strict] extra whitespace after =
+bad/dts-redundant-ws-strict.dts:19: [redundant-whitespace] extra whitespace before ;
+bad/dts-redundant-ws-strict.dts:22: [redundant-whitespace] extra whitespace before {
+bad/dts-redundant-ws-strict.dts:23: [redundant-whitespace] extra whitespace before {
+bad/dts-redundant-ws-strict.dts:23: [redundant-whitespace] extra whitespace after :
+bad/dts-redundant-ws-strict.dts:24: [redundant-whitespace-strict] extra whitespace before =
+bad/dts-redundant-ws-strict.dts:25: [redundant-whitespace-strict] extra whitespace after =
+bad/dts-redundant-ws-strict.dts:26: [redundant-whitespace] extra whitespace before ;
diff --git a/scripts/dtc/dt-style-selftest/expected/dts-redundant-ws.dts.txt b/scripts/dtc/dt-style-selftest/expected/dts-redundant-ws.dts.txt
new file mode 100644
index 000000000000..3b2a989045ed
--- /dev/null
+++ b/scripts/dtc/dt-style-selftest/expected/dts-redundant-ws.dts.txt
@@ -0,0 +1,10 @@
+# mode=relaxed
+bad/dts-redundant-ws.dts:7: [redundant-whitespace] extra whitespace before {
+bad/dts-redundant-ws.dts:13: [redundant-whitespace] extra whitespace before {
+bad/dts-redundant-ws.dts:13: [redundant-whitespace] extra whitespace after :
+bad/dts-redundant-ws.dts:19: [redundant-whitespace] extra whitespace before ;
+bad/dts-redundant-ws.dts:22: [redundant-whitespace] extra whitespace before {
+bad/dts-redundant-ws.dts:23: [redundant-whitespace] extra whitespace before {
+bad/dts-redundant-ws.dts:23: [redundant-whitespace] extra whitespace after :
+bad/dts-redundant-ws.dts:26: [redundant-whitespace] extra whitespace before ;
+bad/dts-redundant-ws.dts:27: [redundant-whitespace] extra whitespace before ;
diff --git a/scripts/dtc/dt-style-selftest/expected/dts-redundant-ws.dtso.txt b/scripts/dtc/dt-style-selftest/expected/dts-redundant-ws.dtso.txt
new file mode 100644
index 000000000000..5f9a63061709
--- /dev/null
+++ b/scripts/dtc/dt-style-selftest/expected/dts-redundant-ws.dtso.txt
@@ -0,0 +1,2 @@
+# mode=strict
+bad/dts-redundant-ws.dtso:5: [redundant-whitespace] extra whitespace before {
diff --git a/scripts/dtc/dt-style-selftest/expected/yaml-redundant-ws-strict.yaml.txt b/scripts/dtc/dt-style-selftest/expected/yaml-redundant-ws-strict.yaml.txt
new file mode 100644
index 000000000000..fbf323832c91
--- /dev/null
+++ b/scripts/dtc/dt-style-selftest/expected/yaml-redundant-ws-strict.yaml.txt
@@ -0,0 +1,5 @@
+# mode=strict
+bad/yaml-redundant-ws-strict.yaml:26: example 0 [redundant-whitespace] extra whitespace before {
+bad/yaml-redundant-ws-strict.yaml:27: example 0 [redundant-whitespace-strict] extra whitespace before =
+bad/yaml-redundant-ws-strict.yaml:28: example 0 [redundant-whitespace-strict] extra whitespace after =
+bad/yaml-redundant-ws-strict.yaml:31: example 0 [redundant-whitespace] extra whitespace before ;
diff --git a/scripts/dtc/dt-style-selftest/expected/yaml-redundant-ws.yaml.txt b/scripts/dtc/dt-style-selftest/expected/yaml-redundant-ws.yaml.txt
new file mode 100644
index 000000000000..a162967e4336
--- /dev/null
+++ b/scripts/dtc/dt-style-selftest/expected/yaml-redundant-ws.yaml.txt
@@ -0,0 +1,4 @@
+# mode=relaxed
+bad/yaml-redundant-ws.yaml:26: example 0 [redundant-whitespace] extra whitespace before {
+bad/yaml-redundant-ws.yaml:29: example 0 [redundant-whitespace] extra whitespace before ;
+bad/yaml-redundant-ws.yaml:30: example 0 [redundant-whitespace] extra whitespace before ;