[PATCH v5 2/5] dt-bindings: pwm: amlogic: Add a new binding for meson8 pwm types

[Jerome Brunet <jbrunet@baylibre.com>]

The binding that is used up to now describe which input the PWM
channel multiplexer should pick among its possible parents,
which are hardcoded in the driver. This isn't a good binding in
the sense that it should describe hardware but not usage.

Add a new binding deprecating the old one that uses clocks in a
better way and how clocks are usually used today: The list of
clocks describe the inputs of the PWM block as they are realised
in hardware.

So deprecate the old bindings and introduce a compatible per SoC
family to replace these.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
---
 .../devicetree/bindings/pwm/pwm-amlogic.yaml  | 50 +++++++++++++++++--
 1 file changed, 47 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/pwm/pwm-amlogic.yaml b/Documentation/devicetree/bindings/pwm/pwm-amlogic.yaml
index a1d382aacb82..1d71d4f8f328 100644
--- a/Documentation/devicetree/bindings/pwm/pwm-amlogic.yaml
+++ b/Documentation/devicetree/bindings/pwm/pwm-amlogic.yaml
@@ -21,23 +21,36 @@ properties:
           - amlogic,meson-g12a-ee-pwm
           - amlogic,meson-g12a-ao-pwm-ab
           - amlogic,meson-g12a-ao-pwm-cd
-          - amlogic,meson-s4-pwm
+        deprecated: true
       - items:
           - const: amlogic,meson-gx-pwm
           - const: amlogic,meson-gxbb-pwm
+        deprecated: true
       - items:
           - const: amlogic,meson-gx-ao-pwm
           - const: amlogic,meson-gxbb-ao-pwm
+        deprecated: true
       - items:
           - const: amlogic,meson8-pwm
           - const: amlogic,meson8b-pwm
+        deprecated: true
+      - enum:
+          - amlogic,meson8-pwm-v2
+          - amlogic,meson-s4-pwm
+      - items:
+          - enum:
+              - amlogic,meson8b-pwm-v2
+              - amlogic,meson-gxbb-pwm-v2
+              - amlogic,meson-axg-pwm-v2
+              - amlogic,meson-g12-pwm-v2
+          - const: amlogic,meson8-pwm-v2
 
   reg:
     maxItems: 1
 
   clocks:
     minItems: 1
-    maxItems: 2
+    maxItems: 4
 
   clock-names:
     minItems: 1
@@ -68,11 +81,14 @@ allOf:
               - amlogic,meson-g12a-ao-pwm-ab
               - amlogic,meson-g12a-ao-pwm-cd
     then:
-      # Historic bindings tied to the driver implementation
+      # Obsolete historic bindings tied to the driver implementation
       # The clocks provided here are meant to be matched with the input
       # known (hard-coded) in the driver and used to select pwm clock
       # source. Currently, the linux driver ignores this.
+      # This is kept to maintain ABI backward compatibility.
       properties:
+        clocks:
+          maxItems: 2
         clock-names:
           oneOf:
             - items:
@@ -81,6 +97,27 @@ allOf:
                 - const: clkin0
                 - const: clkin1
 
+  # Newer binding where clock describe the actual clock inputs of the pwm
+  # block. These are necessary but some inputs may be grounded.
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - amlogic,meson8-pwm-v2
+    then:
+      properties:
+        clocks:
+          minItems: 1
+          items:
+            - description: input clock 0 of the pwm block
+            - description: input clock 1 of the pwm block
+            - description: input clock 2 of the pwm block
+            - description: input clock 3 of the pwm block
+        clock-names: false
+      required:
+        - clocks
+
   # Newer IP block take a single input per channel, instead of 4 inputs
   # for both channels
   - if:
@@ -110,6 +147,13 @@ examples:
       clock-names = "clkin0", "clkin1";
       #pwm-cells = <3>;
     };
+  - |
+    pwm@2000 {
+      compatible = "amlogic,meson8-pwm-v2";
+      reg = <0x1000 0x10>;
+      clocks = <&xtal>, <0>, <&fdiv4>, <&fdiv5>;
+      #pwm-cells = <3>;
+    };
   - |
     pwm@1000 {
       compatible = "amlogic,meson-s4-pwm";
-- 
2.43.0