9 files changed, 240 insertions, 4 deletions

diff --git a/tmk_core/chibios.mk b/tmk_core/chibios.mk
index 733f2d60f..5a3facf8e 100644
--- a/tmk_core/chibios.mk
+++ b/tmk_core/chibios.mk
@@ -71,6 +71,9 @@ else ifneq ("$(wildcard $(TOP_DIR)/platforms/chibios/$(BOARD)/board/board.mk)","
     BOARD_PATH = $(TOP_DIR)/platforms/chibios/$(BOARD)
     BOARD_MK += $(TOP_DIR)/platforms/chibios/$(BOARD)/board/board.mk
     KEYBOARD_PATHS += $(BOARD_PATH)/configs
+    ifneq ("$(wildcard $(BOARD_PATH)/rules.mk)","")
+        include $(BOARD_PATH)/rules.mk
+    endif
 endif
 
 ifeq ("$(wildcard $(BOARD_MK))","")
diff --git a/tmk_core/common.mk b/tmk_core/common.mk
index fdf2aa097..05839824c 100644
--- a/tmk_core/common.mk
+++ b/tmk_core/common.mk
@@ -18,6 +18,7 @@ TMK_COMMON_SRC +=	$(COMMON_DIR)/host.c \
         $(COMMON_DIR)/report.c \
         $(PLATFORM_COMMON_DIR)/suspend.c \
         $(PLATFORM_COMMON_DIR)/timer.c \
+        $(COMMON_DIR)/sync_timer.c \
         $(PLATFORM_COMMON_DIR)/bootloader.c \
 
 ifeq ($(PLATFORM),AVR)
diff --git a/tmk_core/common/keyboard.c b/tmk_core/common/keyboard.c
index 8c7bdc8b5..a1fbc01da 100644
--- a/tmk_core/common/keyboard.c
+++ b/tmk_core/common/keyboard.c
@@ -23,6 +23,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "led.h"
 #include "keycode.h"
 #include "timer.h"
+#include "sync_timer.h"
 #include "print.h"
 #include "debug.h"
 #include "command.h"
@@ -255,6 +256,7 @@ __attribute__((weak)) void housekeeping_task_user(void) {}
  */
 void keyboard_init(void) {
     timer_init();
+    sync_timer_init();
     matrix_init();
 #ifdef VIA_ENABLE
     via_init();
diff --git a/tmk_core/common/mousekey.c b/tmk_core/common/mousekey.c
index ef18bcf1a..697e0692c 100644
--- a/tmk_core/common/mousekey.c
+++ b/tmk_core/common/mousekey.c
@@ -36,6 +36,9 @@ static void           mousekey_debug(void);
 static uint8_t        mousekey_accel        = 0;
 static uint8_t        mousekey_repeat       = 0;
 static uint8_t        mousekey_wheel_repeat = 0;
+#ifdef MK_KINETIC_SPEED
+static uint16_t       mouse_timer     = 0;
+#endif
 
 #ifndef MK_3_SPEED
 
@@ -43,7 +46,7 @@ static uint16_t last_timer_c = 0;
 static uint16_t last_timer_w = 0;
 
 /*
- * Mouse keys  acceleration algorithm
+ * Mouse keys acceleration algorithm
  *  http://en.wikipedia.org/wiki/Mouse_keys
  *
  *  speed = delta * max_speed * (repeat / time_to_max)**((1000+curve)/1000)
@@ -105,6 +108,69 @@ static uint8_t wheel_unit(void) {
 }
 
 #    else /* #ifndef MK_COMBINED */
+#        ifndef MK_KINETIC_SPEED
+
+/*
+ * Kinetic movement  acceleration algorithm
+ *
+ *  current speed = I + A * T/50 + A * 0.5 * T^2 | maximum B
+ *
+ * T: time since the mouse movement started
+ * E: mouse events per second (set through MOUSEKEY_INTERVAL, UHK sends 250, the
+ *    pro micro on my Signum 3.0 sends only 125!)
+ * I: initial speed at time 0
+ * A: acceleration
+ * B: base mouse travel speed
+ */
+const uint16_t mk_accelerated_speed = MOUSEKEY_ACCELERATED_SPEED;
+const uint16_t mk_base_speed = MOUSEKEY_BASE_SPEED;
+const uint16_t mk_decelerated_speed = MOUSEKEY_DECELERATED_SPEED;
+const uint16_t mk_initial_speed = MOUSEKEY_INITIAL_SPEED;
+
+static uint8_t move_unit(void) {
+    float speed = mk_initial_speed;
+
+    if (mousekey_accel & ((1<<0) | (1<<2))) {
+        speed = mousekey_accel & (1<<2) ? mk_accelerated_speed : mk_decelerated_speed;
+    } else if (mousekey_repeat && mouse_timer) {
+        const float time_elapsed = timer_elapsed(mouse_timer) / 50;
+        speed = mk_initial_speed +
+            MOUSEKEY_MOVE_DELTA * time_elapsed +
+            MOUSEKEY_MOVE_DELTA * 0.5 * time_elapsed * time_elapsed;
+
+        speed = speed > mk_base_speed ? mk_base_speed : speed;
+    }
+
+    /* convert speed to USB mouse speed 1 to 127 */
+    speed = (uint8_t)(speed / (1000.0f / mk_interval));
+    speed = speed < 1 ? 1 : speed;
+
+    return speed > MOUSEKEY_MOVE_MAX ? MOUSEKEY_MOVE_MAX : speed;
+}
+
+float mk_wheel_interval = 1000.0f / MOUSEKEY_WHEEL_INITIAL_MOVEMENTS;
+
+static uint8_t wheel_unit(void) {
+    float speed = MOUSEKEY_WHEEL_INITIAL_MOVEMENTS;
+
+    if (mousekey_accel & ((1<<0) | (1<<2))) {
+        speed = mousekey_accel & (1<<2) ? MOUSEKEY_WHEEL_ACCELERATED_MOVEMENTS : MOUSEKEY_WHEEL_DECELERATED_MOVEMENTS;
+    } else if (mousekey_repeat && mouse_timer) {
+        if (mk_wheel_interval != MOUSEKEY_WHEEL_BASE_MOVEMENTS) {
+            const float time_elapsed = timer_elapsed(mouse_timer) / 50;
+            speed = MOUSEKEY_WHEEL_INITIAL_MOVEMENTS +
+                1 * time_elapsed +
+                1 * 0.5 * time_elapsed * time_elapsed;
+        }
+        speed = speed > MOUSEKEY_WHEEL_BASE_MOVEMENTS ? MOUSEKEY_WHEEL_BASE_MOVEMENTS : speed;
+    }
+
+    mk_wheel_interval = 1000.0f / speed;
+
+    return 1;
+}
+
+#        else /* #ifndef MK_KINETIC_SPEED */
 
 static uint8_t move_unit(void) {
     uint16_t unit;
@@ -142,6 +208,7 @@ static uint8_t wheel_unit(void) {
     return (unit > MOUSEKEY_WHEEL_MAX ? MOUSEKEY_WHEEL_MAX : (unit == 0 ? 1 : unit));
 }
 
+#        endif /* #ifndef MK_KINETIC_SPEED */
 #    endif /* #ifndef MK_COMBINED */
 
 void mousekey_task(void) {
@@ -193,6 +260,12 @@ void mousekey_task(void) {
 }
 
 void mousekey_on(uint8_t code) {
+#ifdef MK_KINETIC_SPEED
+    if (mouse_timer == 0) {
+        mouse_timer = timer_read();
+    }
+#endif /* #ifdef MK_KINETIC_SPEED */
+
     if (code == KC_MS_UP)
         mouse_report.y = move_unit() * -1;
     else if (code == KC_MS_DOWN)
@@ -260,7 +333,12 @@ void mousekey_off(uint8_t code) {
         mousekey_accel &= ~(1 << 1);
     else if (code == KC_MS_ACCEL2)
         mousekey_accel &= ~(1 << 2);
-    if (mouse_report.x == 0 && mouse_report.y == 0) mousekey_repeat = 0;
+    if (mouse_report.x == 0 && mouse_report.y == 0) {
+        mousekey_repeat = 0;
+#ifdef MK_KINETIC_SPEED
+        mouse_timer = 0;
+#endif /* #ifdef MK_KINETIC_SPEED */
+    }
     if (mouse_report.v == 0 && mouse_report.h == 0) mousekey_wheel_repeat = 0;
 }
 
diff --git a/tmk_core/common/mousekey.h b/tmk_core/common/mousekey.h
index 05e453823..703854b82 100644
--- a/tmk_core/common/mousekey.h
+++ b/tmk_core/common/mousekey.h
@@ -38,16 +38,28 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #    endif
 
 #    ifndef MOUSEKEY_MOVE_DELTA
+#ifndef MK_KINETIC_SPEED
 #        define MOUSEKEY_MOVE_DELTA 5
+#else
+#        define MOUSEKEY_MOVE_DELTA 25
+#endif
 #    endif
 #    ifndef MOUSEKEY_WHEEL_DELTA
 #        define MOUSEKEY_WHEEL_DELTA 1
 #    endif
 #    ifndef MOUSEKEY_DELAY
+#ifndef MK_KINETIC_SPEED
 #        define MOUSEKEY_DELAY 300
+#else
+#        define MOUSEKEY_DELAY 8
+#endif
 #    endif
 #    ifndef MOUSEKEY_INTERVAL
+#ifndef MK_KINETIC_SPEED
 #        define MOUSEKEY_INTERVAL 50
+#else
+#        define MOUSEKEY_INTERVAL 8
+#endif
 #    endif
 #    ifndef MOUSEKEY_MAX_SPEED
 #        define MOUSEKEY_MAX_SPEED 10
@@ -68,6 +80,31 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #        define MOUSEKEY_WHEEL_TIME_TO_MAX 40
 #    endif
 
+#ifndef MOUSEKEY_INITIAL_SPEED
+#define MOUSEKEY_INITIAL_SPEED  100
+#endif
+#ifndef MOUSEKEY_BASE_SPEED
+#define MOUSEKEY_BASE_SPEED 1000
+#endif
+#ifndef MOUSEKEY_DECELERATED_SPEED
+#define MOUSEKEY_DECELERATED_SPEED 400
+#endif
+#ifndef MOUSEKEY_ACCELERATED_SPEED
+#define MOUSEKEY_ACCELERATED_SPEED 3000
+#endif
+#ifndef MOUSEKEY_WHEEL_INITIAL_MOVEMENTS
+#define MOUSEKEY_WHEEL_INITIAL_MOVEMENTS  16
+#endif
+#ifndef MOUSEKEY_WHEEL_BASE_MOVEMENTS
+#define MOUSEKEY_WHEEL_BASE_MOVEMENTS  32
+#endif
+#ifndef MOUSEKEY_WHEEL_ACCELERATED_MOVEMENTS
+#define MOUSEKEY_WHEEL_ACCELERATED_MOVEMENTS  48
+#endif
+#ifndef MOUSEKEY_WHEEL_DECELERATED_MOVEMENTS
+#define MOUSEKEY_WHEEL_DECELERATED_MOVEMENTS  8
+#endif
+
 #else /* #ifndef MK_3_SPEED */
 
 #    ifndef MK_C_OFFSET_UNMOD
diff --git a/tmk_core/common/sync_timer.c b/tmk_core/common/sync_timer.c
new file mode 100644
index 000000000..de24b463b
--- /dev/null
+++ b/tmk_core/common/sync_timer.c
@@ -0,0 +1,58 @@
+/*
+Copyright (C) 2020 Ryan Caltabiano <https://github.com/XScorpion2>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+If you happen to meet one of the copyright holders in a bar you are obligated
+to buy them one pint of beer.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+
+#include "sync_timer.h"
+#include "keyboard.h"
+
+#if defined(SPLIT_KEYBOARD) && !defined(DISABLE_SYNC_TIMER)
+volatile int32_t sync_timer_ms;
+
+void sync_timer_init(void) { sync_timer_ms = 0; }
+
+void sync_timer_update(uint32_t time) {
+    if (is_keyboard_master()) return;
+    sync_timer_ms = time - timer_read32();
+}
+
+uint16_t sync_timer_read(void) {
+    if (is_keyboard_master()) return timer_read();
+    return sync_timer_read32();
+}
+
+uint32_t sync_timer_read32(void) {
+    if (is_keyboard_master()) return timer_read32();
+    return sync_timer_ms + timer_read32();
+}
+
+uint16_t sync_timer_elapsed(uint16_t last) {
+    if (is_keyboard_master()) return timer_elapsed(last);
+    return TIMER_DIFF_16(sync_timer_read(), last);
+}
+
+uint32_t sync_timer_elapsed32(uint32_t last) {
+    if (is_keyboard_master()) return timer_elapsed32(last);
+    return TIMER_DIFF_32(sync_timer_read32(), last);
+}
+#endif
diff --git a/tmk_core/common/sync_timer.h b/tmk_core/common/sync_timer.h
new file mode 100644
index 000000000..9ddef45bb
--- /dev/null
+++ b/tmk_core/common/sync_timer.h
@@ -0,0 +1,54 @@
+/*
+Copyright (C) 2020 Ryan Caltabiano <https://github.com/XScorpion2>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+If you happen to meet one of the copyright holders in a bar you are obligated
+to buy them one pint of beer.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+
+#pragma once
+
+#include <stdint.h>
+#include "timer.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#if defined(SPLIT_KEYBOARD) && !defined(DISABLE_SYNC_TIMER)
+void     sync_timer_init(void);
+void     sync_timer_update(uint32_t time);
+uint16_t sync_timer_read(void);
+uint32_t sync_timer_read32(void);
+uint16_t sync_timer_elapsed(uint16_t last);
+uint32_t sync_timer_elapsed32(uint32_t last);
+#else
+#    define sync_timer_init()
+#    define sync_timer_clear()
+#    define sync_timer_update(t)
+#    define sync_timer_read() timer_read()
+#    define sync_timer_read32() timer_read32()
+#    define sync_timer_elapsed(t) timer_elapsed(t)
+#    define sync_timer_elapsed32(t) timer_elapsed32(t)
+#endif
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/tmk_core/protocol/arm_atsam/i2c_master.c b/tmk_core/protocol/arm_atsam/i2c_master.c
index d3319ab44..dda2f85b0 100644
--- a/tmk_core/protocol/arm_atsam/i2c_master.c
+++ b/tmk_core/protocol/arm_atsam/i2c_master.c
@@ -28,6 +28,9 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 #    define I2C_LED_USE_DMA 1  // Set 1 to use background DMA transfers for leds, Set 0 to use inline software transfers
 
+DmacDescriptor dmac_desc;
+DmacDescriptor dmac_desc_wb;
+
 static uint8_t i2c_led_q[I2C_Q_SIZE];  // I2C queue circular buffer
 static uint8_t i2c_led_q_s;            // Start of circular buffer
 static uint8_t i2c_led_q_e;            // End of circular buffer
diff --git a/tmk_core/protocol/arm_atsam/i2c_master.h b/tmk_core/protocol/arm_atsam/i2c_master.h
index 44dbdfbff..68773f213 100644
--- a/tmk_core/protocol/arm_atsam/i2c_master.h
+++ b/tmk_core/protocol/arm_atsam/i2c_master.h
@@ -24,8 +24,8 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #    include "issi3733_driver.h"
 #    include "config.h"
 
-__attribute__((__aligned__(16))) DmacDescriptor dmac_desc;
-__attribute__((__aligned__(16))) DmacDescriptor dmac_desc_wb;
+extern __attribute__((__aligned__(16))) DmacDescriptor dmac_desc;
+extern __attribute__((__aligned__(16))) DmacDescriptor dmac_desc_wb;
 
 uint8_t I2C3733_Init_Control(void);
 uint8_t I2C3733_Init_Drivers(void);