Joystick feature improvements (#19052)

2 files changed, 86 insertions, 46 deletions

diff --git a/quantum/joystick.c b/quantum/joystick.c
index d285dcdb5e..057a018dff 100644
--- a/quantum/joystick.c
+++ b/quantum/joystick.c
@@ -19,45 +19,48 @@
 #include "analog.h"
 #include "wait.h"
 
-// clang-format off
-joystick_t joystick_status = {
+joystick_t joystick_state = {
     .buttons = {0},
-    .axes = {
-#if JOYSTICK_AXES_COUNT > 0
-        0
+    .axes =
+        {
+#if JOYSTICK_AXIS_COUNT > 0
+            0
 #endif
-    },
-    .status = 0
+        },
+    .dirty = false,
 };
-// clang-format on
 
 // array defining the reading of analog values for each axis
-__attribute__((weak)) joystick_config_t joystick_axes[JOYSTICK_AXES_COUNT] = {};
+__attribute__((weak)) joystick_config_t joystick_axes[JOYSTICK_AXIS_COUNT] = {};
 
 __attribute__((weak)) void joystick_task(void) {
     joystick_read_axes();
 }
 
 void joystick_flush(void) {
-    if ((joystick_status.status & JS_UPDATED) > 0) {
-        host_joystick_send(&joystick_status);
-        joystick_status.status &= ~JS_UPDATED;
+    if (joystick_state.dirty) {
+        host_joystick_send(&joystick_state);
+        joystick_state.dirty = false;
     }
 }
 
 void register_joystick_button(uint8_t button) {
-    joystick_status.buttons[button / 8] |= 1 << (button % 8);
-    joystick_status.status |= JS_UPDATED;
+    if (button >= JOYSTICK_BUTTON_COUNT) return;
+    joystick_state.buttons[button / 8] |= 1 << (button % 8);
+    joystick_state.dirty = true;
     joystick_flush();
 }
 
 void unregister_joystick_button(uint8_t button) {
-    joystick_status.buttons[button / 8] &= ~(1 << (button % 8));
-    joystick_status.status |= JS_UPDATED;
+    if (button >= JOYSTICK_BUTTON_COUNT) return;
+    joystick_state.buttons[button / 8] &= ~(1 << (button % 8));
+    joystick_state.dirty = true;
     joystick_flush();
 }
 
 int16_t joystick_read_axis(uint8_t axis) {
+    if (axis >= JOYSTICK_AXIS_COUNT) return 0;
+
     // disable pull-up resistor
     writePinLow(joystick_axes[axis].input_pin);
 
@@ -93,24 +96,24 @@ int16_t joystick_read_axis(uint8_t axis) {
     // test the converted value against the lower range
     int32_t ref        = joystick_axes[axis].mid_digit;
     int32_t range      = joystick_axes[axis].min_digit;
-    int32_t ranged_val = ((axis_val - ref) * -JOYSTICK_RESOLUTION) / (range - ref);
+    int32_t ranged_val = ((axis_val - ref) * -JOYSTICK_MAX_VALUE) / (range - ref);
 
     if (ranged_val > 0) {
         // the value is in the higher range
         range      = joystick_axes[axis].max_digit;
-        ranged_val = ((axis_val - ref) * JOYSTICK_RESOLUTION) / (range - ref);
+        ranged_val = ((axis_val - ref) * JOYSTICK_MAX_VALUE) / (range - ref);
     }
 
     // clamp the result in the valid range
-    ranged_val = ranged_val < -JOYSTICK_RESOLUTION ? -JOYSTICK_RESOLUTION : ranged_val;
-    ranged_val = ranged_val > JOYSTICK_RESOLUTION ? JOYSTICK_RESOLUTION : ranged_val;
+    ranged_val = ranged_val < -JOYSTICK_MAX_VALUE ? -JOYSTICK_MAX_VALUE : ranged_val;
+    ranged_val = ranged_val > JOYSTICK_MAX_VALUE ? JOYSTICK_MAX_VALUE : ranged_val;
 
     return ranged_val;
 }
 
 void joystick_read_axes() {
-#if JOYSTICK_AXES_COUNT > 0
-    for (int i = 0; i < JOYSTICK_AXES_COUNT; ++i) {
+#if JOYSTICK_AXIS_COUNT > 0
+    for (int i = 0; i < JOYSTICK_AXIS_COUNT; ++i) {
         if (joystick_axes[i].input_pin == JS_VIRTUAL_AXIS) {
             continue;
         }
@@ -123,8 +126,10 @@ void joystick_read_axes() {
 }
 
 void joystick_set_axis(uint8_t axis, int16_t value) {
-    if (value != joystick_status.axes[axis]) {
-        joystick_status.axes[axis] = value;
-        joystick_status.status |= JS_UPDATED;
+    if (axis >= JOYSTICK_AXIS_COUNT) return;
+
+    if (value != joystick_state.axes[axis]) {
+        joystick_state.axes[axis] = value;
+        joystick_state.dirty      = true;
     }
 }
diff --git a/quantum/joystick.h b/quantum/joystick.h
index ee966fdb1a..0ac99aa590 100644
--- a/quantum/joystick.h
+++ b/quantum/joystick.h
@@ -16,32 +16,41 @@
 
 #pragma once
 
+#include <stdbool.h>
 #include <stdint.h>
+
 #include "gpio.h"
 
+/**
+ * \defgroup joystick
+ *
+ * HID Joystick
+ * \{
+ */
+
 #ifndef JOYSTICK_BUTTON_COUNT
 #    define JOYSTICK_BUTTON_COUNT 8
 #elif JOYSTICK_BUTTON_COUNT > 32
 #    error Joystick feature only supports up to 32 buttons
 #endif
 
-#ifndef JOYSTICK_AXES_COUNT
-#    define JOYSTICK_AXES_COUNT 4
-#elif JOYSTICK_AXES_COUNT > 6
+#ifndef JOYSTICK_AXIS_COUNT
+#    define JOYSTICK_AXIS_COUNT 2
+#elif JOYSTICK_AXIS_COUNT > 6
 #    error Joystick feature only supports up to 6 axes
 #endif
 
-#if JOYSTICK_AXES_COUNT == 0 && JOYSTICK_BUTTON_COUNT == 0
+#if JOYSTICK_AXIS_COUNT == 0 && JOYSTICK_BUTTON_COUNT == 0
 #    error Joystick feature requires at least one axis or button
 #endif
 
-#ifndef JOYSTICK_AXES_RESOLUTION
-#    define JOYSTICK_AXES_RESOLUTION 8
-#elif JOYSTICK_AXES_RESOLUTION < 8 || JOYSTICK_AXES_RESOLUTION > 16
-#    error JOYSTICK_AXES_RESOLUTION must be between 8 and 16
+#ifndef JOYSTICK_AXIS_RESOLUTION
+#    define JOYSTICK_AXIS_RESOLUTION 8
+#elif JOYSTICK_AXIS_RESOLUTION < 8 || JOYSTICK_AXIS_RESOLUTION > 16
+#    error JOYSTICK_AXIS_RESOLUTION must be between 8 and 16
 #endif
 
-#define JOYSTICK_RESOLUTION ((1L << (JOYSTICK_AXES_RESOLUTION - 1)) - 1)
+#define JOYSTICK_MAX_VALUE ((1L << (JOYSTICK_AXIS_RESOLUTION - 1)) - 1)
 
 // configure on input_pin of the joystick_axes array entry to JS_VIRTUAL_AXIS
 // to prevent it from being read from the ADC. This allows outputing forged axis value.
@@ -68,30 +77,56 @@ typedef struct {
     uint16_t max_digit;
 } joystick_config_t;
 
-extern joystick_config_t joystick_axes[JOYSTICK_AXES_COUNT];
-
-enum joystick_status {
-    JS_INITIALIZED = 1,
-    JS_UPDATED,
-};
+extern joystick_config_t joystick_axes[JOYSTICK_AXIS_COUNT];
 
 typedef struct {
     uint8_t buttons[(JOYSTICK_BUTTON_COUNT - 1) / 8 + 1];
-
-    int16_t axes[JOYSTICK_AXES_COUNT];
-    uint8_t status : 2;
+    int16_t axes[JOYSTICK_AXIS_COUNT];
+    bool    dirty;
 } joystick_t;
 
-extern joystick_t joystick_status;
+extern joystick_t joystick_state;
 
 void joystick_task(void);
+
+/**
+ * \brief Send the joystick report to the host, if it has been marked as dirty.
+ */
 void joystick_flush(void);
 
+/**
+ * \brief Set the state of a button, and flush the report.
+ *
+ * \param button The index of the button to press, from 0 to 31.
+ */
 void register_joystick_button(uint8_t button);
+
+/**
+ * \brief Reset the state of a button, and flush the report.
+ *
+ * \param button The index of the button to release, from 0 to 31.
+ */
 void unregister_joystick_button(uint8_t button);
 
+/**
+ * \brief Sample and process the analog value of the given axis.
+ *
+ * \param axis The axis to read.
+ *
+ * \return A signed 16-bit integer, where 0 is the resting or mid point.
+ */
 int16_t joystick_read_axis(uint8_t axis);
-void    joystick_read_axes(void);
-void    joystick_set_axis(uint8_t axis, int16_t value);
+
+void joystick_read_axes(void);
+
+/**
+ * \brief Set the value of the given axis.
+ *
+ * \param axis The axis to set the value of.
+ * \param value The value to set.
+ */
+void joystick_set_axis(uint8_t axis, int16_t value);
 
 void host_joystick_send(joystick_t *joystick);
+
+/** \} */