[Core] Speed up pimoroni trackball driver (#13823)

2 files changed, 153 insertions, 90 deletions

diff --git a/drivers/sensors/pimoroni_trackball.c b/drivers/sensors/pimoroni_trackball.c
index c0ac644f7..48098ff0c 100644
--- a/drivers/sensors/pimoroni_trackball.c
+++ b/drivers/sensors/pimoroni_trackball.c
@@ -1,4 +1,5 @@
 /* Copyright 2020 Christopher Courtney, aka Drashna Jael're  (@drashna) <drashna@live.com>
+ * Copyright 2021 Dasky (@daskygit)
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -13,128 +14,188 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-
 #include "pimoroni_trackball.h"
 #include "i2c_master.h"
+#include "print.h"
 
-static uint8_t scrolling      = 0;
-static int16_t x_offset       = 0;
-static int16_t y_offset       = 0;
-static int16_t h_offset       = 0;
-static int16_t v_offset       = 0;
-static float   precisionSpeed = 1;
+#ifndef PIMORONI_TRACKBALL_ADDRESS
+#    define PIMORONI_TRACKBALL_ADDRESS 0x0A
+#endif
+#ifndef PIMORONI_TRACKBALL_INTERVAL_MS
+#    define PIMORONI_TRACKBALL_INTERVAL_MS 8
+#endif
+#ifndef PIMORONI_TRACKBALL_MOUSE_SCALE
+#    define PIMORONI_TRACKBALL_MOUSE_SCALE 5
+#endif
+#ifndef PIMORONI_TRACKBALL_SCROLL_SCALE
+#    define PIMORONI_TRACKBALL_SCROLL_SCALE 1
+#endif
+#ifndef PIMORONI_TRACKBALL_DEBOUNCE_CYCLES
+#    define PIMORONI_TRACKBALL_DEBOUNCE_CYCLES 20
+#endif
+#ifndef PIMORONI_TRACKBALL_ERROR_COUNT
+#    define PIMORONI_TRACKBALL_ERROR_COUNT 10
+#endif
 
-static uint16_t i2c_timeout_timer;
+#define TRACKBALL_TIMEOUT 100
+#define TRACKBALL_REG_LED_RED 0x00
+#define TRACKBALL_REG_LED_GRN 0x01
+#define TRACKBALL_REG_LED_BLU 0x02
+#define TRACKBALL_REG_LED_WHT 0x03
+#define TRACKBALL_REG_LEFT 0x04
+#define TRACKBALL_REG_RIGHT 0x05
+#define TRACKBALL_REG_UP 0x06
+#define TRACKBALL_REG_DOWN 0x07
 
-#ifndef PIMORONI_I2C_TIMEOUT
-#    define PIMORONI_I2C_TIMEOUT 100
-#endif
-#ifndef I2C_WAITCHECK
-#    define I2C_WAITCHECK 1000
+static pimoroni_data  current_pimoroni_data;
+static report_mouse_t mouse_report;
+static bool           scrolling   = false;
+static int16_t        x_offset    = 0;
+static int16_t        y_offset    = 0;
+static int16_t        h_offset    = 0;
+static int16_t        v_offset    = 0;
+static uint16_t       precision   = 128;
+static uint8_t        error_count = 0;
+
+float trackball_get_precision(void) { return ((float)precision / 128); }
+void  trackball_set_precision(float floatprecision) { precision = (floatprecision * 128); }
+bool  trackball_is_scrolling(void) { return scrolling; }
+void  trackball_set_scrolling(bool scroll) { scrolling = scroll; }
+
+void trackball_set_rgbw(uint8_t r, uint8_t g, uint8_t b, uint8_t w) {
+    uint8_t                              data[4] = {r, g, b, w};
+    __attribute__((unused)) i2c_status_t status  = i2c_writeReg(PIMORONI_TRACKBALL_ADDRESS << 1, TRACKBALL_REG_LED_RED, data, sizeof(data), TRACKBALL_TIMEOUT);
+#ifdef TRACKBALL_DEBUG
+    dprintf("Trackball RGBW i2c_status_t: %d\n", status);
 #endif
-#ifndef MOUSE_DEBOUNCE
-#    define MOUSE_DEBOUNCE 5
+}
+
+i2c_status_t read_pimoroni_trackball(pimoroni_data* data) {
+    i2c_status_t status = i2c_readReg(PIMORONI_TRACKBALL_ADDRESS << 1, TRACKBALL_REG_LEFT, (uint8_t*)data, sizeof(*data), TRACKBALL_TIMEOUT);
+#ifdef TRACKBALL_DEBUG
+    dprintf("Trackball READ i2c_status_t: %d\nLeft: %d\nRight: %d\nUp: %d\nDown: %d\nSwtich: %d\n", status, data->left, data->right, data->up, data->down, data->click);
 #endif
+    return status;
+}
 
-void trackball_set_rgbw(uint8_t red, uint8_t green, uint8_t blue, uint8_t white) {
-    uint8_t data[] = {0x00, red, green, blue, white};
-    i2c_transmit(TRACKBALL_WRITE, data, sizeof(data), PIMORONI_I2C_TIMEOUT);
+__attribute__((weak)) void pointing_device_init(void) {
+    i2c_init();
+    trackball_set_rgbw(0x00, 0x00, 0x00, 0x00);
 }
 
-int16_t mouse_offset(uint8_t positive, uint8_t negative, int16_t scale) {
-    int16_t offset    = (int16_t)positive - (int16_t)negative;
-    int16_t magnitude = (int16_t)(scale * offset * offset * precisionSpeed);
-    return offset < 0 ? -magnitude : magnitude;
+int16_t trackball_get_offsets(uint8_t negative_dir, uint8_t positive_dir, uint8_t scale) {
+    uint8_t offset     = 0;
+    bool    isnegative = false;
+    if (negative_dir > positive_dir) {
+        offset     = negative_dir - positive_dir;
+        isnegative = true;
+    } else {
+        offset = positive_dir - negative_dir;
+    }
+    uint16_t magnitude = (scale * offset * offset * precision) >> 7;
+    return isnegative ? -(int16_t)(magnitude) : (int16_t)(magnitude);
 }
 
-void update_member(int8_t* member, int16_t* offset) {
+void trackball_adapt_values(int8_t* mouse, int16_t* offset) {
     if (*offset > 127) {
-        *member = 127;
+        *mouse = 127;
         *offset -= 127;
     } else if (*offset < -127) {
-        *member = -127;
+        *mouse = -127;
         *offset += 127;
     } else {
-        *member = *offset;
+        *mouse  = *offset;
         *offset = 0;
     }
 }
 
-__attribute__((weak)) void trackball_check_click(bool pressed, report_mouse_t* mouse) {
+__attribute__((weak)) void trackball_click(bool pressed, report_mouse_t* mouse) {
+#ifdef PIMORONI_TRACKBALL_CLICK
     if (pressed) {
         mouse->buttons |= MOUSE_BTN1;
     } else {
         mouse->buttons &= ~MOUSE_BTN1;
     }
+#endif
 }
 
-float trackball_get_precision(void) { return precisionSpeed; }
-void  trackball_set_precision(float precision) { precisionSpeed = precision; }
-bool  trackball_is_scrolling(void) { return scrolling; }
-void  trackball_set_scrolling(bool scroll) { scrolling = scroll; }
+__attribute__((weak)) bool pointing_device_task_user(pimoroni_data* trackball_data) { return true; };
 
-__attribute__((weak)) void pointing_device_init(void) { i2c_init(); trackball_set_rgbw(0x00, 0x00, 0x00, 0x00); }
+__attribute__((weak)) void pointing_device_task() {
+    static fast_timer_t throttle = 0;
+    static uint16_t     debounce = 0;
 
-void pointing_device_task(void) {
-    static bool     debounce;
-    static uint16_t debounce_timer;
-    uint8_t         state[5] = {};
-    if (timer_elapsed(i2c_timeout_timer) > I2C_WAITCHECK) {
-        if (i2c_readReg(TRACKBALL_READ, 0x04, state, 5, PIMORONI_I2C_TIMEOUT) == I2C_STATUS_SUCCESS) {
-            if (!state[4] && !debounce) {
-                if (scrolling) {
+    if (error_count < PIMORONI_TRACKBALL_ERROR_COUNT && timer_elapsed_fast(throttle) >= PIMORONI_TRACKBALL_INTERVAL_MS) {
+        i2c_status_t status = read_pimoroni_trackball(&current_pimoroni_data);
+
+        if (status == I2C_STATUS_SUCCESS) {
+            error_count = 0;
+
+            if (pointing_device_task_user(&current_pimoroni_data)) {
+                mouse_report = pointing_device_get_report();
+
+                if (!(current_pimoroni_data.click & 128)) {
+                    trackball_click(false, &mouse_report);
+                    if (!debounce) {
+                        if (scrolling) {
 #ifdef PIMORONI_TRACKBALL_INVERT_X
-                    h_offset += mouse_offset(state[2], state[3], 1);
+                            h_offset += trackball_get_offsets(current_pimoroni_data.right, current_pimoroni_data.left, PIMORONI_TRACKBALL_SCROLL_SCALE);
 #else
-                    h_offset -= mouse_offset(state[2], state[3], 1);
+                            h_offset -= trackball_get_offsets(current_pimoroni_data.right, current_pimoroni_data.left, PIMORONI_TRACKBALL_SCROLL_SCALE);
 #endif
 #ifdef PIMORONI_TRACKBALL_INVERT_Y
-                    v_offset += mouse_offset(state[1], state[0], 1);
+                            v_offset += trackball_get_offsets(current_pimoroni_data.down, current_pimoroni_data.up, PIMORONI_TRACKBALL_SCROLL_SCALE);
 #else
-                    v_offset -= mouse_offset(state[1], state[0], 1);
+                            v_offset -= trackball_get_offsets(current_pimoroni_data.down, current_pimoroni_data.up, PIMORONI_TRACKBALL_SCROLL_SCALE);
 #endif
-                } else {
+                        } else {
 #ifdef PIMORONI_TRACKBALL_INVERT_X
-                    x_offset -= mouse_offset(state[2], state[3], 5);
+                            x_offset -= trackball_get_offsets(current_pimoroni_data.right, current_pimoroni_data.left, PIMORONI_TRACKBALL_MOUSE_SCALE);
 #else
-                    x_offset += mouse_offset(state[2], state[3], 5);
+                            x_offset += trackball_get_offsets(current_pimoroni_data.right, current_pimoroni_data.left, PIMORONI_TRACKBALL_MOUSE_SCALE);
 #endif
 #ifdef PIMORONI_TRACKBALL_INVERT_Y
-                    y_offset -= mouse_offset(state[1], state[0], 5);
+                            y_offset -= trackball_get_offsets(current_pimoroni_data.down, current_pimoroni_data.up, PIMORONI_TRACKBALL_MOUSE_SCALE);
 #else
-                    y_offset += mouse_offset(state[1], state[0], 5);
+                            y_offset += trackball_get_offsets(current_pimoroni_data.down, current_pimoroni_data.up, PIMORONI_TRACKBALL_MOUSE_SCALE);
 #endif
-                }
-            } else {
-                if (state[4]) {
-                    debounce       = true;
-                    debounce_timer = timer_read();
+                        }
+                        if (scrolling) {
+#ifndef PIMORONI_TRACKBALL_ROTATE
+                            trackball_adapt_values(&mouse_report.h, &h_offset);
+                            trackball_adapt_values(&mouse_report.v, &v_offset);
+#else
+                            trackball_adapt_values(&mouse_report.h, &v_offset);
+                            trackball_adapt_values(&mouse_report.v, &h_offset);
+#endif
+                            mouse_report.x = 0;
+                            mouse_report.y = 0;
+                        } else {
+#ifndef PIMORONI_TRACKBALL_ROTATE
+                            trackball_adapt_values(&mouse_report.x, &x_offset);
+                            trackball_adapt_values(&mouse_report.y, &y_offset);
+#else
+                            trackball_adapt_values(&mouse_report.x, &y_offset);
+                            trackball_adapt_values(&mouse_report.y, &x_offset);
+#endif
+                            mouse_report.h = 0;
+                            mouse_report.v = 0;
+                        }
+                    } else {
+                        debounce--;
+                    }
+                } else {
+                    trackball_click(true, &mouse_report);
+                    debounce = PIMORONI_TRACKBALL_DEBOUNCE_CYCLES;
                 }
             }
         } else {
-            i2c_timeout_timer = timer_read();
+            error_count++;
         }
-    }
-
-    if (timer_elapsed(debounce_timer) > MOUSE_DEBOUNCE) debounce = false;
 
-    report_mouse_t mouse = pointing_device_get_report();
-
-#ifdef PIMORONI_TRACKBALL_CLICK
-    trackball_check_click(state[4] & (1 << 7), &mouse);
-#endif
+        pointing_device_set_report(mouse_report);
+        pointing_device_send();
 
-#ifndef PIMORONI_TRACKBALL_ROTATE
-    update_member(&mouse.x, &x_offset);
-    update_member(&mouse.y, &y_offset);
-    update_member(&mouse.h, &h_offset);
-    update_member(&mouse.v, &v_offset);
-#else
-    update_member(&mouse.x, &y_offset);
-    update_member(&mouse.y, &x_offset);
-    update_member(&mouse.h, &v_offset);
-    update_member(&mouse.v, &h_offset);
-#endif
-    pointing_device_set_report(mouse);
-    pointing_device_send();
+        throttle = timer_read_fast();
+    }
 }
diff --git a/drivers/sensors/pimoroni_trackball.h b/drivers/sensors/pimoroni_trackball.h
index 9e3c64c19..6b2a41425 100644
--- a/drivers/sensors/pimoroni_trackball.h
+++ b/drivers/sensors/pimoroni_trackball.h
@@ -1,4 +1,5 @@
 /* Copyright 2020 Christopher Courtney, aka Drashna Jael're  (@drashna) <drashna@live.com>
+ * Copyright 2021 Dasky (@daskygit)
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -13,23 +14,24 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-
 #pragma once
 
 #include "quantum.h"
 #include "pointing_device.h"
 
-#ifndef TRACKBALL_ADDRESS
-#    define TRACKBALL_ADDRESS 0x0A
-#endif
-#define TRACKBALL_WRITE ((TRACKBALL_ADDRESS << 1) | I2C_WRITE)
-#define TRACKBALL_READ (TRACKBALL_ADDRESS << 1)
-
-void trackball_set_rgbw(uint8_t red, uint8_t green, uint8_t blue, uint8_t white);
-void trackball_check_click(bool pressed, report_mouse_t *mouse);
-void trackball_register_button(bool pressed, enum mouse_buttons button);
+typedef struct pimoroni_data {
+    uint8_t left;
+    uint8_t right;
+    uint8_t up;
+    uint8_t down;
+    uint8_t click;
+} pimoroni_data;
 
-float trackball_get_precision(void);
-void  trackball_set_precision(float precision);
-bool  trackball_is_scrolling(void);
-void  trackball_set_scrolling(bool scroll);
+void    trackball_set_rgbw(uint8_t red, uint8_t green, uint8_t blue, uint8_t white);
+void    trackball_click(bool pressed, report_mouse_t* mouse);
+int16_t trackball_get_offsets(uint8_t negative_dir, uint8_t positive_dir, uint8_t scale);
+void    trackball_adapt_values(int8_t* mouse, int16_t* offset);
+float   trackball_get_precision(void);
+void    trackball_set_precision(float precision);
+bool    trackball_is_scrolling(void);
+void    trackball_set_scrolling(bool scroll);