Update the main TI TWL-family binding to be self-contained and to fix
pre-existing validation errors.

To ensure future patches are bisectable, child nodes whose bindings
are in other patches (audio, keypad, usb, etc.) are now defined using
a flexible 'additionalProperties: true' pattern. This removes hard
dependencies between the MFD and subsystem bindings.

The complete dtbs_check for this binding is clean except for two
warnings originating from pre-existing bugs in the OMAP DTS files,
for which fixes have already been submitted separately [1][2].

Signed-off-by: Jihed Chaibi <redacted>

---
Changes in v7:
  - Moved twl4030/twl6030-specific child node definitions (audio, usb..)
    into the conditional 'if/then' block to improve schema accuracy.

Changes in v6:
  - Refactored the ti,twl4030-power compatible schema to be much stricter,
    removing obsolete board-specific compatibles (-n900, -beagleboard-xm),
    that were added in v5. The schema now only permits specific, valid
    fallback combinations. This change is supported by subsequent patches
    in the same series (2/3) & (3/3), which update the affected DTS files.
  - Enforced the presence of the compatible property on all relevant
    sub-nodes by adding 'required: - compatible', closing a key validation
    loophole.
  - Applied various formatting cleanups for readability and correctness.

Changes in v5:
  - Restructured the entire binding to define properties at the top
    level instead of if/then blocks, per maintainer feedback.
  - Added specific compatible enums for new child nodes instead of a
    generic 'compatible: true'.
  - Set 'unevaluatedProperties: false' for 'pwm' and 'pwmled' nodes to
    enforce strict validation.
  - Expanded 'power' node compatible enum to include all board-specific
    compatible strings (used in existing device trees, e.g. OMAP3-based
    boards) for more complete coverage.
  - Corrected the schema for the 'power' node compatible to properly
    handle single and fallback entries.

Changes in v4:
  - Reworked binding to be independent and bisectable per maintainer
    feedback by using 'additionalProperties: true' for child nodes.
  - Added board-specific compatibles to the 'power' node enum.
  - Added definitions for 'clocks' and 'clock-names' properties.
  - Renamed 'twl6030-usb' child node to 'usb-comparator' to match
    existing Device Tree usage (twl6030.dtsi).
  - Fixed some spelling/grammar erros in the description.

Changes in v3:
  - New patch to consolidate simple bindings (power, pwm) and add
    definitions for all child nodes to fix dtbs_check validation
    errors found in v2.

Changes in v2:
  - This patch is split from larger series [3] per maintainer feedback.
  - Added missing sub-node definitions, resolving dtbs_check errors.

[1] https://lore.kernel.org/all/20250822222530.113520-1-jihed.chaibi.dev@gmail.com/ (local)
[2] https://lore.kernel.org/all/20250822225052.136919-1-jihed.chaibi.dev@gmail.com/ (local)
[3] https://lore.kernel.org/all/20250816021523.167049-1-jihed.chaibi.dev@gmail.com/ (local)
---
 .../devicetree/bindings/mfd/ti,twl.yaml       | 232 +++++++++++++++++-
 .../devicetree/bindings/mfd/twl4030-power.txt |  48 ----
 .../devicetree/bindings/pwm/ti,twl-pwm.txt    |  17 --
 .../devicetree/bindings/pwm/ti,twl-pwmled.txt |  17 --
 4 files changed, 221 insertions(+), 93 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/mfd/twl4030-power.txt
 delete mode 100644 Documentation/devicetree/bindings/pwm/ti,twl-pwm.txt
 delete mode 100644 Documentation/devicetree/bindings/pwm/ti,twl-pwmled.txt

diff --git a/Documentation/devicetree/bindings/mfd/ti,twl.yaml b/Documentation/devicetree/bindings/mfd/ti,twl.yaml
index f162ab60c09b..95238a10ecda 100644
--- a/Documentation/devicetree/bindings/mfd/ti,twl.yaml
+++ b/Documentation/devicetree/bindings/mfd/ti,twl.yaml

@@ -9,11 +9,13 @@ title: Texas Instruments TWL family
 maintainers:
   - Andreas Kemnade <andreas@kemnade.info>
 
-description: |
+description: >

   The TWLs are Integrated Power Management Chips.
-  Some version might contain much more analog function like
+
+  Some versions might contain much more analog functionality like
   USB transceiver or Audio amplifier.
-  These chips are connected to an i2c bus.
+
+  These chips are connected to an I2C bus.
 
 allOf:
   - if:

@@ -62,6 +64,7 @@ allOf:
         pwrbutton:
           type: object
           additionalProperties: false
+
           properties:
             compatible:
               const: ti,twl4030-pwrbutton

@@ -73,9 +76,109 @@ allOf:
         watchdog:
           type: object
           additionalProperties: false
+
           properties:
             compatible:
               const: ti,twl4030-wdt
+
+        audio: