3 files changed, 199 insertions, 0 deletions
diff --git a/quantum/painter/lvgl/qp_lvgl.c b/quantum/painter/lvgl/qp_lvgl.c
new file mode 100644
index 0000000000..c6dd08ef97
--- /dev/null
+++ b/quantum/painter/lvgl/qp_lvgl.c
@@ -0,0 +1,150 @@
+// Copyright 2022 Jose Pablo Ramirez (@jpe230)
+// Copyright 2022 Nick Brassel (@tzarc)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "qp_lvgl.h"
+#include "timer.h"
+#include "deferred_exec.h"
+#include "lvgl.h"
+
+typedef struct lvgl_state_t {
+    uint8_t        fnc_id; // Ideally this should be the pointer of the function to run
+    uint16_t       delay_ms;
+    deferred_token defer_token;
+} lvgl_state_t;
+
+static deferred_executor_t lvgl_executors[2] = {0}; // For lv_tick_inc and lv_task_handler
+static lvgl_state_t        lvgl_states[2]    = {0}; // For lv_tick_inc and lv_task_handler
+
+painter_device_t selected_display = NULL;
+void *           color_buffer     = NULL;
+
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// Quantum Painter LVGL Integration Internal: qp_lvgl_flush
+
+void qp_lvgl_flush(lv_disp_drv_t *disp, const lv_area_t *area, lv_color_t *color_p) {
+    if (selected_display) {
+        uint32_t number_pixels = (area->x2 - area->x1 + 1) * (area->y2 - area->y1 + 1);
+        qp_viewport(selected_display, area->x1, area->y1, area->x2, area->y2);
+        qp_pixdata(selected_display, (void *)color_p, number_pixels);
+        qp_flush(selected_display);
+        lv_disp_flush_ready(disp);
+    }
+}
+
+static uint32_t tick_task_callback(uint32_t trigger_time, void *cb_arg) {
+    lvgl_state_t *  state     = (lvgl_state_t *)cb_arg;
+    static uint32_t last_tick = 0;
+    switch (state->fnc_id) {
+        case 0: {
+            uint32_t now = timer_read32();
+            lv_tick_inc(TIMER_DIFF_32(now, last_tick));
+            last_tick = now;
+        } break;
+        case 1:
+            lv_task_handler();
+            break;
+
+        default:
+            break;
+    }
+
+    // The tasks should run indefinitely
+    return state->delay_ms;
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// Quantum Painter LVGL Integration API: qp_lvgl_attach
+
+bool qp_lvgl_attach(painter_device_t device) {
+    qp_dprintf("qp_lvgl_start: entry\n");
+    qp_lvgl_detach();
+
+    struct painter_driver_t *driver = (struct painter_driver_t *)device;
+    if (!driver->validate_ok) {
+        qp_dprintf("qp_lvgl_attach: fail (validation_ok == false)\n");
+        qp_lvgl_detach();
+        return false;
+    }
+
+    // Setting up the tasks
+    lvgl_state_t *lv_tick_inc_state = &lvgl_states[0];
+    lv_tick_inc_state->fnc_id       = 0;
+    lv_tick_inc_state->delay_ms     = 1;
+    lv_tick_inc_state->defer_token  = defer_exec_advanced(lvgl_executors, 2, 1, tick_task_callback, lv_tick_inc_state);
+
+    if (lv_tick_inc_state->defer_token == INVALID_DEFERRED_TOKEN) {
+        qp_dprintf("qp_lvgl_attach: fail (could not set up qp_lvgl executor)\n");
+        qp_lvgl_detach();
+        return false;
+    }
+
+    lvgl_state_t *lv_task_handler_state = &lvgl_states[1];
+    lv_task_handler_state->fnc_id       = 1;
+    lv_task_handler_state->delay_ms     = 5;
+    lv_task_handler_state->defer_token  = defer_exec_advanced(lvgl_executors, 2, 5, tick_task_callback, lv_task_handler_state);
+
+    if (lv_task_handler_state->defer_token == INVALID_DEFERRED_TOKEN) {
+        qp_dprintf("qp_lvgl_attach: fail (could not set up qp_lvgl executor)\n");
+        qp_lvgl_detach();
+        return false;
+    }
+
+    // Init LVGL
+    lv_init();
+
+    // Set up lvgl display buffer
+    static lv_disp_draw_buf_t draw_buf;
+    // Allocate a buffer for 1/10 screen size
+    const size_t count_required = driver->panel_width * driver->panel_height / 10;
+    color_buffer                = color_buffer ? realloc(color_buffer, sizeof(lv_color_t) * count_required) : malloc(sizeof(lv_color_t) * count_required);
+    if (!color_buffer) {
+        qp_dprintf("qp_lvgl_attach: fail (could not set up memory buffer)\n");
+        qp_lvgl_detach();
+        return false;
+    }
+    memset(color_buffer, 0, sizeof(lv_color_t) * count_required);
+    // Initialize the display buffer.
+    lv_disp_draw_buf_init(&draw_buf, color_buffer, NULL, count_required);
+
+    selected_display = device;
+
+    uint16_t panel_width, panel_height, offset_x, offset_y;
+    qp_get_geometry(selected_display, &panel_width, &panel_height, NULL, &offset_x, &offset_y);
+
+    panel_width -= offset_x;
+    panel_height -= offset_y;
+
+    // Setting up display driver
+    static lv_disp_drv_t disp_drv;     /*Descriptor of a display driver*/
+    lv_disp_drv_init(&disp_drv);       /*Basic initialization*/
+    disp_drv.flush_cb = qp_lvgl_flush; /*Set your driver function*/
+    disp_drv.draw_buf = &draw_buf;     /*Assign the buffer to the display*/
+    disp_drv.hor_res  = panel_width;   /*Set the horizontal resolution of the display*/
+    disp_drv.ver_res  = panel_height;  /*Set the vertical resolution of the display*/
+    lv_disp_drv_register(&disp_drv);   /*Finally register the driver*/
+
+    return true;
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// Quantum Painter LVGL Integration API: qp_lvgl_detach
+
+void qp_lvgl_detach(void) {
+    for (int i = 0; i < 2; ++i) {
+        cancel_deferred_exec_advanced(lvgl_executors, 2, lvgl_states[i].defer_token);
+    }
+    if (color_buffer) {
+        free(color_buffer);
+        color_buffer = NULL;
+    }
+    selected_display = NULL;
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// Quantum Painter LVGL Integration Internal: qp_lvgl_internal_tick
+
+void qp_lvgl_internal_tick(void) {
+    static uint32_t last_lvgl_exec = 0;
+    deferred_exec_advanced_task(lvgl_executors, 2, &last_lvgl_exec);
+}
diff --git a/quantum/painter/lvgl/qp_lvgl.h b/quantum/painter/lvgl/qp_lvgl.h
new file mode 100644
index 0000000000..d9ad5e8df1
--- /dev/null
+++ b/quantum/painter/lvgl/qp_lvgl.h
@@ -0,0 +1,25 @@
+// Copyright 2022 Jose Pablo Ramirez (@jpe230)
+// Copyright 2022 Nick Brassel (@tzarc)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include "qp.h"
+#include "lvgl.h"
+
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// Quantum Painter - LVGL External API
+
+/**
+ * Sets up LVGL with the supplied display.
+ *
+ * @param device[in] the handle of the device to control
+ * @return true if init. of LVGL succeeded
+ * @return false if init. of LVGL failed
+ */
+bool qp_lvgl_attach(painter_device_t device);
+
+/**
+ * Disconnects LVGL from any attached display
+ */
+void qp_lvgl_detach(void);
diff --git a/quantum/painter/lvgl/rules.mk b/quantum/painter/lvgl/rules.mk
new file mode 100644
index 0000000000..50226941b3
--- /dev/null
+++ b/quantum/painter/lvgl/rules.mk
@@ -0,0 +1,24 @@
+# LVGL Integration
+
+OPT_DEFS += -DQUANTUM_PAINTER_LVGL_INTEGRATION_ENABLE -DLV_CONF_INCLUDE_SIMPLE
+DEFERRED_EXEC_ENABLE := yes
+
+LVGL_DIR_NAME = lvgl
+LVGL_DIR = $(LIB_DIR)
+LVGL_PATH = $(LVGL_DIR)/$(LVGL_DIR_NAME)
+
+COMMON_VPATH += $(PLATFORM_PATH) \
+                $(QUANTUM_DIR)/painter/$(LVGL_DIR_NAME) \
+                $(LVGL_PATH)
+
+include $(LVGL_PATH)/src/extra/extra.mk
+include $(LVGL_PATH)/src/core/lv_core.mk
+include $(LVGL_PATH)/src/draw/lv_draw.mk
+include $(LVGL_PATH)/src/draw/sw/lv_draw_sw.mk
+include $(LVGL_PATH)/src/font/lv_font.mk
+include $(LVGL_PATH)/src/hal/lv_hal.mk
+include $(LVGL_PATH)/src/misc/lv_misc.mk
+include $(LVGL_PATH)/src/widgets/lv_widgets.mk
+
+SRC += qp_lvgl.c \
+       $(CSRCS)