[PATCH v3 2/3] dt-bindings: watchdog: fsl-imx: document suspend in wait mode

[Andrej Picej <andrej.picej@norik.com>]

Property "fsl,suspend-in-wait" suspends watchdog in "WAIT" mode which
corresponds to Linux's Suspend-to-Idle S0 mode. If this property is not
set and the device is put into Suspend-to-Idle mode, the watchdog
triggers a reset after 128 seconds.

Signed-off-by: Andrej Picej <andrej.picej@norik.com>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
---
Changes in v3:
 - disallow the property for devices which don't support WDW bit
   functionality with .yaml DTS allOf:if:then scheme.

Changes in v2:
 - add a commit message,
 - add a list of devices which support this functionality
---
 .../bindings/watchdog/fsl-imx-wdt.yaml        | 33 +++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.yaml b/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.yaml
index fb7695515be1..12de8bbc8460 100644
--- a/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.yaml
+++ b/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.yaml
@@ -55,6 +55,12 @@ properties:
       If present, the watchdog device is configured to assert its
       external reset (WDOG_B) instead of issuing a software reset.
 
+  fsl,suspend-in-wait:
+    $ref: /schemas/types.yaml#/definitions/flag
+    description: |
+      If present, the watchdog device is suspended in WAIT mode
+      (Suspend-to-Idle). Only supported on certain devices.
+
 required:
   - compatible
   - interrupts
@@ -62,6 +68,33 @@ required:
 
 unevaluatedProperties: false
 
+allOf:
+  - if:
+      not:
+        properties:
+          compatible:
+            contains:
+              enum:
+                - fsl,imx25-wdt
+                - fsl,imx35-wdt
+                - fsl,imx50-wdt
+                - fsl,imx51-wdt
+                - fsl,imx53-wdt
+                - fsl,imx6q-wdt
+                - fsl,imx6sl-wdt
+                - fsl,imx6sll-wdt
+                - fsl,imx6sx-wdt
+                - fsl,imx6ul-wdt
+                - fsl,imx7d-wdt
+                - fsl,imx8mm-wdt
+                - fsl,imx8mn-wdt
+                - fsl,imx8mp-wdt
+                - fsl,imx8mq-wdt
+                - fsl,vf610-wdt
+    then:
+      properties:
+        fsl,suspend-in-wait: false
+
 examples:
   - |
     #include <dt-bindings/interrupt-controller/arm-gic.h>
-- 
2.25.1