[PATCH v3 4/5] dt-bindings: dma: fsl-edma: add fsl,imx8ulp-edma compatible string

[Frank Li]

From: Joy Zou <joy.zou@xxxxxxx>

Introduce the compatible string 'fsl,imx8ulp-edma' to enable support for
the i.MX8ULP's eDMA, alongside adjusting the clock numbering. The i.MX8ULP
eDMA architecture features one clock for each DMA channel and an additional
clock for the core controller. Given a maximum of 32 DMA channels, the
maximum clock number consequently increases to 33.

Signed-off-by: Joy Zou <joy.zou@xxxxxxx>
Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
---

Notes:
     Changes in v3:
        - Change clock name form CHXX-CLK to chxx
        - Fix typeo 'clock'
        - Add dma-cell description
        - About clock-names:
          items:
            oneOf:
              - const: dma
              - pattern: ...
    
        Which already detect naming wrong, for example:
    
        clock-names = "dma", "ch00", "ch01", "ch02", "ch03",
                      ....
                      "ch28", "ch29", "ch30", "abcc";
    
        arch/arm64/boot/dts/freescale/imx8ulp-evk.dtb: dma-controller@29010000: clock-names:32: 'oneOf' conditional failed, one must be fixed:
                'dma' was expected
                'abcc' does not match '^ch(0[0-9]|[1-2][0-9]|3[01])$'
    
        Only lose order check, such as ch00, dma, ch03, ch02, can pass check.
        I think it is good enough.
    
        I tried rob's suggestion, but met some technology issue. Detail see
    
        https://lore.kernel.org/imx/20240229-8ulp_edma-v2-0-9d12f883c8f7@xxxxxxx/T/#mc5767dd505d4b7cfc66586a0631684a57e735476

 .../devicetree/bindings/dma/fsl,edma.yaml          | 40 ++++++++++++++++++++--
 1 file changed, 38 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/dma/fsl,edma.yaml b/Documentation/devicetree/bindings/dma/fsl,edma.yaml
index aa51d278cb67b..825f4715499e5 100644
--- a/Documentation/devicetree/bindings/dma/fsl,edma.yaml
+++ b/Documentation/devicetree/bindings/dma/fsl,edma.yaml
@@ -23,6 +23,7 @@ properties:
           - fsl,imx7ulp-edma
           - fsl,imx8qm-adma
           - fsl,imx8qm-edma
+          - fsl,imx8ulp-edma
           - fsl,imx93-edma3
           - fsl,imx93-edma4
           - fsl,imx95-edma5
@@ -43,6 +44,17 @@ properties:
     maxItems: 64
 
   "#dma-cells":
+    description: |
+      Specifies the number of cells needed to encode an DMA channel.
+
+      Encode for cells number 2:
+        cell 0: index of dma channel mux instance.
+        cell 1: peripheral dma request id.
+
+      Encode for cells number 3:
+        cell 0: peripheral dma request id.
+        cell 1: dma channel priority.
+        cell 2: bitmask, defined at include/dt-bindings/dma/fsl-edma.h
     enum:
       - 2
       - 3
@@ -53,11 +65,11 @@ properties:
 
   clocks:
     minItems: 1
-    maxItems: 2
+    maxItems: 33
 
   clock-names:
     minItems: 1
-    maxItems: 2
+    maxItems: 33
 
   big-endian:
     description: |
@@ -108,6 +120,7 @@ allOf:
       properties:
         clocks:
           minItems: 2
+          maxItems: 2
         clock-names:
           items:
             - const: dmamux0
@@ -136,6 +149,7 @@ allOf:
       properties:
         clock:
           minItems: 2
+          maxItems: 2
         clock-names:
           items:
             - const: dma
@@ -151,6 +165,28 @@ allOf:
         dma-channels:
           const: 32
 
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: fsl,imx8ulp-edma
+    then:
+      properties:
+        clocks:
+          minItems: 33
+        clock-names:
+          minItems: 33
+          items:
+            oneOf:
+              - const: dma
+              - pattern: "^ch(0[0-9]|[1-2][0-9]|3[01])$"
+
+        interrupt-names: false
+        interrupts:
+          minItems: 32
+        "#dma-cells":
+          const: 3
+
 unevaluatedProperties: false
 
 examples:

-- 
2.34.1