Joystick 16-bit support

docs/feature_joystick.md

@@ -141,6 +141,19 @@ bool process_record_user(uint16_t keycode, keyrecord_t *record) {
 }
 ```
 
+### Axis Resolution
+
+For use-cases where a higher joystick-precision is desired, it is possible to increase axis precision to a maximum of 16-bit.  
+To use higher axis values, in this example 12-bit, i.e. from -2047 to 2047, add the following line to your config.h:
+
+``` 
+// Max 16
+#define JOYSTICK_AXES_RESOLUTION 12
+```  
+
+
+ This setting works for virtual axes as well as analog axis reading using 
+`JOYSTICK_AXIS_IN(...)`, `JOYSTICK_AXIS_IN_OUT(...)` or `JOYSTICK_AXIS_IN_OUT_GROUND(...)`.
 ### Triggering Joystick Buttons
 
 Joystick buttons are normal Quantum keycodes, defined as `JS_BUTTON0` to `JS_BUTTON31`, depending on the number of buttons you have configured.

quantum/process_keycode/process_joystick.c

@@ -126,20 +126,30 @@ bool process_joystick_analogread_quantum() {
         int16_t axis_val = joystick_axes[axis_index].mid_digit;
 #    endif
 
+
+
+#   if JOYSTICK_AXES_RESOLUTION < 16
+        int32_t js_max = (1 << (JOYSTICK_AXES_RESOLUTION-1)) - 1;
+        int32_t js_min = -js_max;
+#   else 
+        int32_t js_max = 32767;
+        int32_t js_min = -32767;
+#   endif
+
         // test the converted value against the lower range
         int32_t ref        = joystick_axes[axis_index].mid_digit;
         int32_t range      = joystick_axes[axis_index].min_digit;
-        int32_t ranged_val = ((axis_val - ref) * -127) / (range - ref);
+        int32_t ranged_val = ((axis_val - ref) * js_min) / (range - ref);
 
         if (ranged_val > 0) {
             // the value is in the higher range
             range      = joystick_axes[axis_index].max_digit;
-            ranged_val = ((axis_val - ref) * 127) / (range - ref);
+            ranged_val = ((axis_val - ref) * js_max) / (range - ref);
         }
 
         // clamp the result in the valid range
-        ranged_val = ranged_val < -127 ? -127 : ranged_val;
-        ranged_val = ranged_val > 127 ? 127 : ranged_val;
+        ranged_val = ranged_val < js_min ? js_min : ranged_val;
+        ranged_val = ranged_val > js_max ? js_max : ranged_val;
 
         if (ranged_val != joystick_status.axes[axis_index]) {
             joystick_status.axes[axis_index] = ranged_val;

quantum/process_keycode/process_joystick.h

@@ -3,6 +3,10 @@
 #include <stdint.h>
 #include "quantum.h"
 
+#   ifndef JOYSTICK_AXES_RESOLUTION
+        #define JOYSTICK_AXES_RESOLUTION 8
+#   endif
+
 bool process_joystick(uint16_t keycode, keyrecord_t *record);
 
 void joystick_task(void);

tmk_core/common/report.h

@@ -192,7 +192,7 @@ typedef struct {
 
 typedef struct {
 #if JOYSTICK_AXES_COUNT > 0
-    int8_t axes[JOYSTICK_AXES_COUNT];
+    int16_t axes[JOYSTICK_AXES_COUNT];
 #endif
 
 #if JOYSTICK_BUTTON_COUNT > 0

tmk_core/protocol/usb_descriptor.c

@@ -308,11 +308,22 @@ const USB_Descriptor_HIDReport_Datatype_t PROGMEM JoystickReport[] = {
             HID_RI_USAGE(8, 0x35),      // Rz
 #    endif
 #    if JOYSTICK_AXES_COUNT >= 1
-            HID_RI_LOGICAL_MINIMUM(8, -127),
-            HID_RI_LOGICAL_MAXIMUM(8, 127),
+     # if JOYSTICK_AXES_RESOLUTION <8 ||  JOYSTICK_AXES_RESOLUTION > 16
+            #   error Joystick Axes Resolution has to be between 8 and 16            
+     # endif
+     # if JOYSTICK_AXES_RESOLUTION == 16
+            HID_RI_LOGICAL_MINIMUM(16, -32767),
+            HID_RI_LOGICAL_MAXIMUM(16, 32767),
             HID_RI_REPORT_COUNT(8, JOYSTICK_AXES_COUNT),
-            HID_RI_REPORT_SIZE(8, 0x08),
+            HID_RI_REPORT_SIZE(8, 0x10),
+            HID_RI_INPUT(8, HID_IOF_DATA | HID_IOF_VARIABLE | HID_IOF_ABSOLUTE),
+     # else
+            HID_RI_LOGICAL_MINIMUM(16, (1 << (JOYSTICK_AXES_RESOLUTION-1)) - 1),
+            HID_RI_LOGICAL_MAXIMUM(16, -((1 << (JOYSTICK_AXES_RESOLUTION-1)) - 1)),
+            HID_RI_REPORT_COUNT(8, JOYSTICK_AXES_COUNT),
+            HID_RI_REPORT_SIZE(8, 0x10),
             HID_RI_INPUT(8, HID_IOF_DATA | HID_IOF_VARIABLE | HID_IOF_ABSOLUTE),
+     # endif
 #    endif
 
 #    if JOYSTICK_BUTTON_COUNT >= 1

tmk_core/protocol/usb_descriptor.h

@@ -49,6 +49,10 @@
 #    include "hal.h"
 #endif
 
+#   ifndef JOYSTICK_AXES_RESOLUTION
+        #define JOYSTICK_AXES_RESOLUTION 8
+#   endif
+
 /*
  * USB descriptor structure
  */
@@ -261,3 +265,5 @@ enum usb_endpoints {
 
 uint16_t get_usb_descriptor(const uint16_t wValue, const uint16_t wIndex, const void** const DescriptorAddress);
 #endif
+
+