Add support for glitch delay configuration. A detected signal is valid
only if it remains stable longer than the configured delay; otherwise,
it is considered a glitch.

This property was introduced for the i.MX6UL touchscreen controller (TSC),
which provides a hardware deglitch filter with four thresholds depending
on the IPG clock frequency. In this use case, the IPG clock rate is 66 MHz,
resulting in thresholds of 124 µs, 62 µs, 31 µs, and 15 µs, which requires
a property with microsecond-level resolution.

Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>

---

Changes in v6:
- Rename touchscreen-glitch-threshold-ns to debounce-delay-us.
- Update and improve the commit message

Changes in v5:
- Add Acked-by tag of Conor Dooley

Changes in v2:
- Added in v2.

 .../devicetree/bindings/input/touchscreen/touchscreen.yaml    | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Documentation/devicetree/bindings/input/touchscreen/touchscreen.yaml b/Documentation/devicetree/bindings/input/touchscreen/touchscreen.yaml
index 3e3572aa483a..7023e8c73a7b 100644
--- a/Documentation/devicetree/bindings/input/touchscreen/touchscreen.yaml
+++ b/Documentation/devicetree/bindings/input/touchscreen/touchscreen.yaml
@@ -206,6 +206,10 @@ properties:
 
         unevaluatedProperties: false
 
+  debounce-delay-us:
+    description: Minimum duration in microseconds a signal must remain stable
+      to be considered valid.
+
 dependencies:
   touchscreen-size-x: [ touchscreen-size-y ]
   touchscreen-size-y: [ touchscreen-size-x ]
-- 
2.43.0