Initial potentiometer support

docs/_summary.md

@@ -123,6 +123,7 @@
     * [LED Indicators](feature_led_indicators.md)
     * [MIDI](feature_midi.md)
     * [Pointing Device](feature_pointing_device.md)
+    * [Potentiometer](feature_potentiometers.md)
     * [PS/2 Mouse](feature_ps2_mouse.md)
     * [Split Keyboard](feature_split_keyboard.md)
     * [Stenography](feature_stenography.md)

docs/feature_potentiometers.md

@@ -0,0 +1,35 @@
+# Potentiometers
+
+Add this to your `rules.mk`:
+
+```make
+POTENTIOMETER_ENABLE = yes
+```
+
+and this to your `config.h`:
+
+```c
+#define POTENTIOMETER_PINS { B0 }
+```
+
+## Callbacks
+
+The callback functions can be inserted into your `<keyboard>.c`:
+
+```c
+bool potentiometer_update_kb(uint8_t index, uint16_t value) {
+    if (!potentiometer_update_user(index, value)) {
+        midi_send_cc(&midi_device, 2, 0x3E, 0x7F + value);
+    }
+    return true;
+}
+```
+
+or `keymap.c`:
+
+```c
+bool potentiometer_update_user(uint8_t index, uint16_t value) {
+    midi_send_cc(&midi_device, 2, 0x3E, 0x7F + value);
+    return false;
+}
+```

docs/reference_info_json.md

@@ -480,6 +480,17 @@ Configures [One Shot keys](one_shot_keys.md).
     * `timeout`
         * The amount of time before the key is released in milliseconds.
 
+## Potentiometer :id=potentiometer
+
+Configures the [Potentiometer](feature_Potentiometers.md) feature.
+
+* `potentiometer`
+    * `enabled`
+        * Enable the Potentiometer feature.
+        * Default: `false`
+    * `pins` (Required)
+        * The GPIO pin(s) connected to the Potentiometer(s).
+
 ## PS/2 :id=ps2
 
 Configures the [PS/2](feature_ps2_mouse.md) feature.