[PATCH v10 3/4] dt-bindings: input: pwm-beeper: add volume

[Manuel Traut <manuel.traut@mt.com>]

Adds an array of supported volume levels and a default volume level.

Signed-off-by: Manuel Traut <manuel.traut@mt.com>
---
 .../devicetree/bindings/input/pwm-beeper.yaml   | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/Documentation/devicetree/bindings/input/pwm-beeper.yaml b/Documentation/devicetree/bindings/input/pwm-beeper.yaml
index 1ebc3a46d934..6599e28ba5e6 100644
--- a/Documentation/devicetree/bindings/input/pwm-beeper.yaml
+++ b/Documentation/devicetree/bindings/input/pwm-beeper.yaml
@@ -25,6 +25,21 @@ properties:
   beeper-hz:
     description: bell frequency in Hz
 
+  volume-levels-bp:
+    description: >
+      Array of PWM duty cycle values that correspond to
+      linear volume levels. These need to be in the range of
+      0 to 5000, while 0 means 0% duty cycle (mute) and 5000
+      means 50% duty cycle (max volume).
+      Please note that the actual volume of most beepers is
+      highly non-linear, which means that low volume levels
+      are probably somewhere in the range of 10 to 300 (0.1-3%
+      duty cycle).
+
+  default-volume-level-bp:
+    description: >
+      The default volume level.
+
 required:
   - compatible
   - pwms
@@ -36,4 +51,6 @@ examples:
     beeper {
       compatible = "pwm-beeper";
       pwms = <&pwm0>;
+      volume-levels-bp = <0 80 200 400 5000>;
+      default-volume-level-bp = <80>;
     };
-- 
2.39.1