dt-bindings: remoteproc: qcom,msm8916-mss-pil: Add MSM8226

Add support for external power block headswitch (BHS) registers.
Similarly to MSM8974 also MSM8226 has the mx voltage rail exposed as
regulator and only cx voltage rail as power domain.

Signed-off-by: Matti Lehtimäki <matti.lehtimaki@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Luca Weiss <luca@lucaweiss.eu>
Link: https://lore.kernel.org/r/20250217-msm8226-modem-v5-2-2bc74b80e0ae@lucaweiss.eu
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

Documentation/devicetree/bindings/remoteproc/qcom,msm8916-mss-pil.yaml

@@ -17,6 +17,7 @@ properties:
   compatible:
     oneOf:
       - enum:
+          - qcom,msm8226-mss-pil
           - qcom,msm8909-mss-pil
           - qcom,msm8916-mss-pil
           - qcom,msm8953-mss-pil
@@ -70,7 +71,7 @@ properties:
     items:
       - description: CX proxy power domain (control handed over after startup)
       - description: MX proxy power domain (control handed over after startup)
-                     (not valid for qcom,msm8974-mss-pil)
+                     (not valid for qcom,msm8226-mss-pil or qcom,msm8974-mss-pil)
       - description: MSS proxy power domain (control handed over after startup)
                      (only valid for qcom,msm8953-mss-pil)
     minItems: 1
@@ -78,7 +79,7 @@ properties:
   power-domain-names:
     items:
       - const: cx
-      - const: mx # not valid for qcom,msm8974-mss-pil
+      - const: mx # not valid for qcom,msm8226-mss-pil or qcom,msm8974-mss-pil
       - const: mss # only valid for qcom,msm8953-mss-pil
     minItems: 1
 
@@ -107,6 +108,15 @@ properties:
     items:
       - const: stop
 
+  qcom,ext-bhs-reg:
+    $ref: /schemas/types.yaml#/definitions/phandle-array
+    description: External power block headswitch (BHS) register
+                 (only valid for qcom,msm8226-mss-pil)
+    items:
+      - items:
+          - description: phandle to external BHS syscon region
+          - description: offset to the external BHS register
+
   qcom,halt-regs:
     $ref: /schemas/types.yaml#/definitions/phandle-array
     description:
@@ -230,6 +240,7 @@ allOf:
         compatible:
           contains:
             enum:
+              - qcom,msm8226-mss-pil
               - qcom,msm8974-mss-pil
     then:
       properties:
@@ -240,6 +251,17 @@ allOf:
       required:
         - mx-supply
 
+  - if:
+      properties:
+        compatible:
+          const: qcom,msm8226-mss-pil
+    then:
+      required:
+        - qcom,ext-bhs-reg
+    else:
+      properties:
+        qcom,ext-bhs-reg: false
+
   - if:
       properties:
         compatible: