Move classes to separate files.

esp/cpp/07_lcd-panel/CMakeLists.txt

@@ -9,7 +9,7 @@ include($ENV{IDF_PATH}/tools/cmake/project.cmake)
 project(
     #[[NAME]]   lcd-panel
     VERSION     0.1
-    DESCRIPTION "Example of using the SSDLCD"
+    DESCRIPTION "Example of using the SSD1306 LCD display with ESP-IDF and LVGL"
     LANGUAGES   CXX
 )
 # For writing pure cmake components, see the documentation

esp/cpp/07_lcd-panel/main/CMakeLists.txt

@@ -1,5 +1,5 @@
 idf_component_register(
-    SRCS main.cpp display.cpp
+    SRCS main.cpp display.cpp panel_device.cpp ssd1306.cpp
-    INCLUDE_DIRS "."
+    INCLUDE_DIRS .
     REQUIRES driver
 )

esp/cpp/07_lcd-panel/main/display.cpp

@@ -1,6 +1,8 @@
-#include "display.h"
-#include "widgets/label/lv_label.h"
 
+#include "display.h"
+#include "ssd1306.h"
+
+#include "widgets/label/lv_label.h"
 #include <esp_log.h>
 #include <esp_lcd_panel_ops.h>
 #include <esp_heap_caps.h>
@@ -11,9 +13,6 @@
 #include <driver/i2c_master.h>
 #include <mutex>
 
-// To use LV_COLOR_FORMAT_I1 we need an extra buffer to hold the converted data.
-uint8_t Display::oled_buffer_[LCD_H_RES * LCD_V_RES / 8];
-
 // LVGL library is not thread-safe, this example calls LVGL APIs from tasks.
 // We must use a mutex to protect it.
 _lock_t ScopedLock::lock_;
@@ -136,7 +135,7 @@ void Display::lvgl_flush_cb(lv_display_t *display, const lv_area_t *area,
 
       // Write to the buffer as required for the display.
       // It writes only 1-bit for monochrome displays mapped vertically.
-      uint8_t *buf = oled_buffer_ + hor_res * (y >> 3) + (x);
+      uint8_t *buf = SSD1306::oled_buffer_ + hor_res * (y >> 3) + (x);
       if (chroma_color) {
         (*buf) &= ~(1 << (y % 8));
       } else {
@@ -147,7 +146,7 @@ void Display::lvgl_flush_cb(lv_display_t *display, const lv_area_t *area,
   // Pass the draw buffer to the driver.
   ESP_ERROR_CHECK(
       esp_lcd_panel_draw_bitmap(panel_handle, x1, y1, x2 + 1, y2 + 1,
-                                oled_buffer_));
+                                SSD1306::oled_buffer_));
 }
 
 void Display::lvgl_increase_tick(void *)
@@ -156,11 +155,10 @@ void Display::lvgl_increase_tick(void *)
   lv_tick_inc(LVGL_TICK_PERIOD_MS);
 }
 
-void Display::lvgl_port_task(void *)
+[[noreturn]] void Display::lvgl_port_task(void *)
 {
   ESP_LOGI(TAG, "Starting LVGL task");
-  uint32_t time_till_next_ms = 0;
+  for (uint32_t time_till_next_ms = 0; true;) {
-  while (1) {
     _lock_acquire(&ScopedLock::lock_);
     time_till_next_ms = lv_timer_handler();
     _lock_release(&ScopedLock::lock_);
@@ -184,7 +182,15 @@ I2C::I2C() : i2c_bus_(nullptr)
   ESP_ERROR_CHECK(i2c_new_master_bus(&bus_config, &i2c_bus_));
 }
 
-Panel::Panel(i2c_master_bus_handle_t i2c) : io_handle_(nullptr), panel_(nullptr)
+Panel::Panel(i2c_master_bus_handle_t i2c) :
+    io_handle_(nullptr),
+    panel_(nullptr),
+    panel_config_(
+        {
+            .reset_gpio_num = PIN_RST,
+            .bits_per_pixel = 1,
+        }
+    )
 {
   ESP_LOGI(TAG, "Install panel IO");
   esp_lcd_panel_io_i2c_config_t io_config = {
@@ -200,21 +206,9 @@ Panel::Panel(i2c_master_bus_handle_t i2c) : io_handle_(nullptr), panel_(nullptr)
 
   ESP_LOGI(TAG, "Install SSD1306 panel driver");
   SSD1306 ssd1306({.height = LCD_V_RES});
-  panel_config_ = {
-      .reset_gpio_num = PIN_RST,
-      .bits_per_pixel = 1,
-  };
   ssd1306.create_panel(panel_config_, io_handle_, panel_);
 
   ESP_ERROR_CHECK(esp_lcd_panel_reset(panel_));
   ESP_ERROR_CHECK(esp_lcd_panel_init(panel_));
   ESP_ERROR_CHECK(esp_lcd_panel_disp_on_off(panel_, true));
 }
-
-SSD1306::SSD1306(esp_lcd_panel_ssd1306_config_t ssd_config,
-                 int width,
-                 int height) :
-    PanelDevice<esp_lcd_panel_ssd1306_config_t>(width, height)
-{
-  vendor_config_ = ssd_config;
-}

esp/cpp/07_lcd-panel/main/display.h

@@ -12,31 +12,15 @@
 #include "display/lv_display.h"
 #include "widgets/label/lv_label.h"
 
+#include "panel_device.h"
+
 #define I2C_BUS_PORT  0
 #define LVGL_TICK_PERIOD_MS    5
 #define LVGL_TASK_STACK_SIZE   (4 * 1024)
 #define LVGL_TASK_PRIORITY     2
-#define LVGL_PALETTE_SIZE      8
 
 static const char *TAG = "lcd-panel";
 
-// According to SSD1306 datasheet
-// https://www.digikey.com/en/products/detail/winstar-display/WEA012864DWPP3N00003/20533255
-// Bit number used to represent command and parameter
-#define SCREEN_WIDTH           128  // OLED display width, in pixels.
-#define SCREEN_HEIGHT          64  // OLED display height, in pixels.
-#define LCD_H_RES              SCREEN_WIDTH
-#define LCD_V_RES              SCREEN_HEIGHT
-#define I2C_HW_ADDR            0x3C
-#define LCD_PIXEL_CLOCK_HZ     (400 * 1000)
-#define LCD_CMD_BITS           8
-#define LCD_PARAM_BITS         8
-
-// Pin may vary based on your schematic.
-#define PIN_SDA                GPIO_NUM_21
-#define PIN_SCL                GPIO_NUM_22
-#define PIN_RST                -1
-
 struct I2C {
   I2C();
 
@@ -55,67 +39,6 @@ struct ScopedLock {
   static _lock_t lock_;
 };
 
-template<typename T>
-class PanelDevice {
-public:
-  PanelDevice(size_t width, size_t height) : width_(width), height_(height) { }
-
-  ~PanelDevice() = default;
-
-  [[nodiscard]] size_t get_width() const { return width_; }
-
-  [[nodiscard]] size_t get_height() const { return height_; }
-
-  [[nodiscard]] size_t get_area() const { return width_ * height_; }
-
-  [[nodiscard]] size_t get_draw_buffer_size() const
-  {
-    // LVGL reserves 2x4 bytes in the buffer to be used as a palette.
-    return width_ * height_ / 8 + LVGL_PALETTE_SIZE;
-  }
-
-  [[nodiscard]] lv_display_t *create_display() const
-  {
-    return lv_display_create(width_, height_);
-  }
-
-  [[nodiscard]] T &get_vendor_config() const { return vendor_config_; }
-
-  void create_panel(esp_lcd_panel_dev_config_t &panel_config,
-                    esp_lcd_panel_io_handle_t io_handle,
-                    esp_lcd_panel_handle_t &panel_handle);
-
-private:
-  size_t width_;
-  size_t height_;
-
-protected:
-  T vendor_config_;
-};
-
-template<typename T>
-void PanelDevice<T>::create_panel(esp_lcd_panel_dev_config_t &config,
-                                  esp_lcd_panel_io_handle_t io,
-                                  esp_lcd_panel_handle_t &panel)
-{
-  // If the passed handle is already allocated, delete it.
-  if (panel != nullptr) {
-    esp_lcd_panel_del(panel);
-  }
-
-  // Set the vendor config and allocate a new panel handle.
-  config.vendor_config = &vendor_config_;
-  ESP_ERROR_CHECK(esp_lcd_new_panel_ssd1306(io, &config, &panel));
-}
-
-class SSD1306 : public PanelDevice<esp_lcd_panel_ssd1306_config_t> {
-public:
-  explicit SSD1306(esp_lcd_panel_ssd1306_config_t ssd_config,
-                   int width = SCREEN_WIDTH, int height = SCREEN_HEIGHT);
-
-  ~SSD1306() = default;
-};
-
 class Panel {
 public:
   explicit Panel(i2c_master_bus_handle_t i2c);
@@ -170,10 +93,7 @@ public:
 
   static void lvgl_increase_tick(void *arg);
 
-  static void lvgl_port_task(void *arg);
+  [[noreturn]] static void lvgl_port_task(void *arg);
-
-  // For LV_COLOR_FORMAT_I1 we need an extra buffer to hold the converted data.
-  static uint8_t oled_buffer_[LCD_H_RES * LCD_V_RES / 8];
 
 private:
   Panel panel_;

esp/cpp/07_lcd-panel/main/panel_device.cpp

@@ -0,0 +1,2 @@
+
+#include "panel_device.h"

esp/cpp/07_lcd-panel/main/panel_device.h

@@ -0,0 +1,65 @@
+#ifndef PANEL_DEVICE_H
+#define PANEL_DEVICE_H
+
+#include <esp_lcd_panel_dev.h>
+#include <esp_lcd_panel_ops.h>
+#include <esp_lcd_panel_ssd1306.h>
+#include "display/lv_display.h"
+
+#define LVGL_PALETTE_SIZE      8
+
+template<typename T>
+class PanelDevice {
+public:
+  PanelDevice(size_t width, size_t height) : width_(width), height_(height) { }
+
+  ~PanelDevice() = default;
+
+  [[nodiscard]] size_t get_width() const { return width_; }
+
+  [[nodiscard]] size_t get_height() const { return height_; }
+
+  [[nodiscard]] size_t get_area() const { return width_ * height_; }
+
+  [[nodiscard]] size_t get_draw_buffer_size() const
+  {
+    // LVGL reserves 2x4 bytes in the buffer to be used as a palette.
+    return width_ * height_ / 8 + LVGL_PALETTE_SIZE;
+  }
+
+  [[nodiscard]] lv_display_t *create_display() const
+  {
+    return lv_display_create(width_, height_);
+  }
+
+  [[nodiscard]] T &get_vendor_config() const { return vendor_config_; }
+
+  void create_panel(esp_lcd_panel_dev_config_t &panel_config,
+                    esp_lcd_panel_io_handle_t io_handle,
+                    esp_lcd_panel_handle_t &panel_handle);
+
+private:
+  size_t width_;
+  size_t height_;
+
+protected:
+  T vendor_config_;
+};
+
+template<typename T>
+void PanelDevice<T>::create_panel(esp_lcd_panel_dev_config_t &config,
+                                  esp_lcd_panel_io_handle_t io,
+                                  esp_lcd_panel_handle_t &panel)
+{
+  // If the passed handle is already allocated, delete it.
+  if (panel != nullptr) {
+    esp_lcd_panel_del(panel);
+  }
+
+  // Set the vendor config and allocate a new panel handle.
+  config.vendor_config = &vendor_config_;
+  // TODO: This needs moved to SSD1306
+  ESP_ERROR_CHECK(esp_lcd_new_panel_ssd1306(io, &config, &panel));
+}
+
+#endif // PANEL_DEVICE_H

esp/cpp/07_lcd-panel/main/ssd1306.cpp

@@ -0,0 +1,13 @@
+
+#include "ssd1306.h"
+
+// To use LV_COLOR_FORMAT_I1 we need an extra buffer to hold the converted data.
+uint8_t SSD1306::oled_buffer_[LCD_H_RES * LCD_V_RES / 8];
+
+SSD1306::SSD1306(esp_lcd_panel_ssd1306_config_t ssd_config,
+                 int width,
+                 int height) :
+    PanelDevice<esp_lcd_panel_ssd1306_config_t>(width, height)
+{
+  vendor_config_ = ssd_config;
+}

esp/cpp/07_lcd-panel/main/ssd1306.h

@@ -0,0 +1,36 @@
+#ifndef SSD1306_H
+#define SSD1306_H
+
+#include <esp_lcd_panel_ssd1306.h>
+
+#include "panel_device.h"
+
+// According to SSD1306 datasheet
+// https://www.digikey.com/en/products/detail/winstar-display/WEA012864DWPP3N00003/20533255
+// Bit number used to represent command and parameter
+#define SCREEN_WIDTH           128  // OLED display width, in pixels.
+#define SCREEN_HEIGHT          64  // OLED display height, in pixels.
+#define LCD_H_RES              SCREEN_WIDTH
+#define LCD_V_RES              SCREEN_HEIGHT
+#define I2C_HW_ADDR            0x3C
+#define LCD_PIXEL_CLOCK_HZ     (400 * 1000)
+#define LCD_CMD_BITS           8
+#define LCD_PARAM_BITS         8
+
+// Pin may vary based on your schematic.
+#define PIN_SDA                GPIO_NUM_21
+#define PIN_SCL                GPIO_NUM_22
+#define PIN_RST                -1
+
+class SSD1306 : public PanelDevice<esp_lcd_panel_ssd1306_config_t> {
+public:
+  explicit SSD1306(esp_lcd_panel_ssd1306_config_t ssd_config,
+                   int width = SCREEN_WIDTH, int height = SCREEN_HEIGHT);
+
+  ~SSD1306() = default;
+
+  // For LV_COLOR_FORMAT_I1 we need an extra buffer to hold the converted data.
+  static uint8_t oled_buffer_[LCD_H_RES * LCD_V_RES / 8];
+};
+
+#endif // SSD1306_H