[PATCH v3 0/4] ARM: dts: imx: fix ldb related CHECK_DTBS warnings

[PATCH v3 0/4] ARM: dts: imx: fix ldb related CHECK_DTBS warnings

[Frank.Li]

Fix ldb related CHECK_DTBS warnings

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
Changes in v3:
- add ranges
- collect rob's acked-by tags
- Link to v2: https://patch.msgid.link/20260718-arm_dts_ldb-v2-0-f5669571aa2b@nxp.com

Changes in v2:
- Remove status = disabled at binding example
- collect rob's reviewed-by tags.
- Link to v1: https://patch.msgid.link/20260708-arm_dts_ldb-v1-0-4f5579b85797@nxp.com

---
Frank Li (4):
      dt-bindings: display: bridge: ldb: allow a single reg for fsl,imx6sx-ldb
      dt-bindings: soc: imx-iomuxc-gpr: allow bridge@18 as child node
      dt-bindings: display: lcdif: Allow display0 child node for i.MX6UL
      ARM: dts: imx6ul-tx6ul: rename disp0 to display0

 .../bindings/display/bridge/fsl,ldb.yaml           | 23 ++++----
 .../devicetree/bindings/display/fsl,lcdif.yaml     |  1 +
 .../bindings/soc/imx/fsl,imx-iomuxc-gpr.yaml       | 62 ++++++++++++++++++++++
 arch/arm/boot/dts/nxp/imx/imx6ul-tx6ul.dtsi        |  2 +-
 4 files changed, 78 insertions(+), 10 deletions(-)
---
base-commit: 6c94b38b83a04c43ea49004275f0391404051093
change-id: 20260708-arm_dts_ldb-9ca4c548dded

Best regards,
--  
Frank Li <Frank.Li@nxp.com>

[PATCH v3 1/4] dt-bindings: display: bridge: ldb: allow a single reg for fsl,imx6sx-ldb

[Frank.Li]

From: Frank Li <Frank.Li@nxp.com>

The i.MX6SX LDB only provides a single register region for the LDB block,
while other supported LDB variants require two register regions.

Update the binding schema to allow a single reg entry for
fsl,imx6sx-ldb while keeping the existing constraints unchanged for the
other compatible strings.

Fix below DTB_CHECK warings:
  arch/arm/boot/dts/nxp/imx/imx6sx-nitrogen6sx.dtb: bridge@18 (fsl,imx6sx-ldb): reg: [[24, 4]] is too short

Acked-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
Related two theads:
- https://lore.kernel.org/imx/178154922879.1630652.11500293336634076421.robh@kernel.org/

Mixing the addressable and non-addressable child nodes is allowed according to discussion [1].

Link: https://lore.kernel.org/all/n6akxiayi3g6gxcqhreb4iaohmeokoalnqup6h5r2fwdt4zijt@u2wyps55ayqm/ [1]
---
 .../bindings/display/bridge/fsl,ldb.yaml           | 23 +++++++++++++---------
 1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/Documentation/devicetree/bindings/display/bridge/fsl,ldb.yaml b/Documentation/devicetree/bindings/display/bridge/fsl,ldb.yaml
index 7f380879fffdf..e5a8870bb76a6 100644
--- a/Documentation/devicetree/bindings/display/bridge/fsl,ldb.yaml
+++ b/Documentation/devicetree/bindings/display/bridge/fsl,ldb.yaml
@@ -28,9 +28,11 @@ properties:
     const: ldb
 
   reg:
+    minItems: 1
     maxItems: 2
 
   reg-names:
+    minItems: 1
     items:
       - const: ldb
       - const: lvds
@@ -83,15 +85,6 @@ allOf:
         ports:
           properties:
             port@2: false
-  - if:
-      not:
-        properties:
-          compatible:
-            contains:
-              const: fsl,imx6sx-ldb
-    then:
-      required:
-        - reg-names
 
   - if:
       properties:
@@ -100,7 +93,19 @@ allOf:
             const: fsl,imx6sx-ldb
     then:
       properties:
+        reg:
+          maxItems: 1
+        reg-names:
+          maxItems: 1
         nxp,enable-termination-resistor: false
+    else:
+      required:
+        - reg-names
+      properties:
+        reg:
+          minItems: 2
+        reg-names:
+          minItems: 2
 
 additionalProperties: false
 

-- 
2.43.0

[PATCH v3 2/4] dt-bindings: soc: imx-iomuxc-gpr: allow bridge@18 as child node

[Frank.Li]

From: Frank Li <Frank.Li@nxp.com>

The legacy i.MX6SX (>15 year) SoC imx-iomuxc-gpr contains one LDB_CTRL
register. Allow the LVDS Display Bridge(LDB) child node under
imx-iomuxc-gpr.

Fix below CHECK_DTBS warnings:
  arch/arm/boot/dts/nxp/imx/imx6sx-nitrogen6sx.dtb: syscon@20e4000 (fsl,imx6sx-iomuxc-gpr): '#address-cells', '#size-cells', 'bridge@18' do not match any of the regexes: '^ipu[12]_csi[01]_mux$', '^pinctrl-[0-9]+$

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
change in v3
- add ranges

changes in v2
- remote status = "disabled" in example
---
 .../bindings/soc/imx/fsl,imx-iomuxc-gpr.yaml       | 62 ++++++++++++++++++++++
 1 file changed, 62 insertions(+)

diff --git a/Documentation/devicetree/bindings/soc/imx/fsl,imx-iomuxc-gpr.yaml b/Documentation/devicetree/bindings/soc/imx/fsl,imx-iomuxc-gpr.yaml
index 721a67e84c137..49813adce71c7 100644
--- a/Documentation/devicetree/bindings/soc/imx/fsl,imx-iomuxc-gpr.yaml
+++ b/Documentation/devicetree/bindings/soc/imx/fsl,imx-iomuxc-gpr.yaml
@@ -47,10 +47,23 @@ properties:
   reg:
     maxItems: 1
 
+  '#address-cells':
+    const: 1
+
+  '#size-cells':
+    const: 1
+
+  ranges: true
+
   mux-controller:
     type: object
     $ref: /schemas/mux/reg-mux.yaml
 
+  bridge@18:
+    type: object
+    $ref: /schemas/display/bridge/fsl,ldb.yaml#
+    unevaluatedProperties: false
+
 patternProperties:
   "^ipu[12]_csi[01]_mux$":
     type: object
@@ -67,6 +80,19 @@ allOf:
       patternProperties:
         '^ipu[12]_csi[01]_mux$': false
 
+  - if:
+      properties:
+        compatible:
+          not:
+            contains:
+              const: fsl,imx6sx-iomuxc-gpr
+    then:
+      properties:
+        bridge@18: false
+        '#address-cells': false
+        '#size-cells': false
+        ranges: false
+
 additionalProperties: false
 
 required:
@@ -87,4 +113,40 @@ examples:
         };
     };
 
+  - |
+    #include <dt-bindings/clock/imx6sx-clock.h>
+
+    syscon@20e4000 {
+        compatible = "fsl,imx6sx-iomuxc-gpr", "fsl,imx6q-iomuxc-gpr", "syscon", "simple-mfd";
+        reg = <0x020e4000 0x4000>;
+        #address-cells = <1>;
+        #size-cells = <1>;
+        ranges;
+
+        bridge@18 {
+            compatible = "fsl,imx6sx-ldb";
+            reg = <0x18 0x4>;
+            clocks = <&clks IMX6SX_CLK_LDB_DI0>;
+            clock-names = "ldb";
+
+            ports {
+                #address-cells = <1>;
+                #size-cells = <0>;
+
+                port@0 {
+                    reg = <0>;
+
+                    endpoint {
+                    };
+                };
+
+                port@1 {
+                    reg = <1>;
+
+                    endpoint {
+                    };
+                };
+            };
+        };
+    };
 ...

-- 
2.43.0

[PATCH v3 3/4] dt-bindings: display: lcdif: Allow display0 child node for i.MX6UL

[Frank.Li]

From: Frank Li <Frank.Li@nxp.com>

The legacy i.MX6UL LCDIF binding uses a display0 child node to describe
the attached display. Update the binding schema to allow this child node
for fsl,imx6ul-lcdif.

Fixes the following CHECK_DTBS warning:
  arch/arm/boot/dts/nxp/imx/imx6ul-tx6ul-0010.dtb: lcdif@21c8000 (fsl,imx6ul-lcdif): 'disp0' does not match any of the regexes: '^pinctrl-[0-9]+$'

A follow-up patch renames the child node from disp0 to display0 to match
the updated binding.

Acked-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
sashiko report problem and allow dma/dma-names for i.MX6ul. which should
be fine for this kinds of old platform.

Ideally it should use port. but platform is too old to avoid break back
compatiblity and leave as it. Needn't complex if-else branch.
---
 Documentation/devicetree/bindings/display/fsl,lcdif.yaml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/display/fsl,lcdif.yaml b/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
index 2dd0411ec6516..2b123ddf06841 100644
--- a/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
+++ b/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
@@ -182,6 +182,7 @@ allOf:
             contains:
               enum:
                 - fsl,imx28-lcdif
+                - fsl,imx6ul-lcdif
     then:
       properties:
         dmas: false

-- 
2.43.0

[PATCH v3 4/4] ARM: dts: imx6ul-tx6ul: rename disp0 to display0

[Frank.Li]

From: Frank Li <Frank.Li@nxp.com>

Change node name disp0 to display0 to match binding define.

Fix the following CHECK_DTBS warning:
  arch/arm/boot/dts/nxp/imx/imx6ul-tx6ul-0010.dtb: lcdif@21c8000 (fsl,imx6ul-lcdif): 'disp0' does not match any of the regexes: '^pinctrl-[0-9]+$'

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
 arch/arm/boot/dts/nxp/imx/imx6ul-tx6ul.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/nxp/imx/imx6ul-tx6ul.dtsi b/arch/arm/boot/dts/nxp/imx/imx6ul-tx6ul.dtsi
index 192c6a95ae589..2f6916c0359c5 100644
--- a/arch/arm/boot/dts/nxp/imx/imx6ul-tx6ul.dtsi
+++ b/arch/arm/boot/dts/nxp/imx/imx6ul-tx6ul.dtsi
@@ -369,7 +369,7 @@ &lcdif {
 	display = <&display>;
 	status = "okay";
 
-	display: disp0 {
+	display: display0 {
 		bits-per-pixel = <32>;
 		bus-width = <24>;
 		status = "okay";

-- 
2.43.0

Re: [PATCH v3 2/4] dt-bindings: soc: imx-iomuxc-gpr: allow bridge@18 as child node

[Rob Herring (Arm)]

On Thu, 23 Jul 2026 15:14:16 -0400, Frank.Li@oss.nxp.com wrote:
> From: Frank Li <Frank.Li@nxp.com>
> 
> The legacy i.MX6SX (>15 year) SoC imx-iomuxc-gpr contains one LDB_CTRL
> register. Allow the LVDS Display Bridge(LDB) child node under
> imx-iomuxc-gpr.
> 
> Fix below CHECK_DTBS warnings:
>   arch/arm/boot/dts/nxp/imx/imx6sx-nitrogen6sx.dtb: syscon@20e4000 (fsl,imx6sx-iomuxc-gpr): '#address-cells', '#size-cells', 'bridge@18' do not match any of the regexes: '^ipu[12]_csi[01]_mux$', '^pinctrl-[0-9]+$
> 
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
> change in v3
> - add ranges
> 
> changes in v2
> - remote status = "disabled" in example
> ---
>  .../bindings/soc/imx/fsl,imx-iomuxc-gpr.yaml       | 62 ++++++++++++++++++++++
>  1 file changed, 62 insertions(+)
> 

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>