dt-bindings: touchscreen: add debounce-delay-us property

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>
Link: https://lore.kernel.org/r/20250923143746.2857292-4-dario.binacchi@amarulasolutions.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

diff --git a/Documentation/devicetree/bindings/input/touchscreen/touchscreen.yaml b/Documentation/devicetree/bindings/input/touchscreen/touchscreen.yaml
index 3e3572aa483ae7df9e85aaa026f00672ce0dadd6..7023e8c73a7b2e7e732721162fb41ffa702c5173 100644 (file)
--- 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 ]