🚸 TFT backlight PWM / brightness (#22841)

Marlin/src/lcd/dogm/marlinui_DOGM.cpp

 
 void MarlinUI::clear_lcd() { } // Automatically cleared by Picture Loop
 
+#if HAS_LCD_BRIGHTNESS
+  void MarlinUI::_set_brightness() {
+    #if PIN_EXISTS(TFT_BACKLIGHT)
+      if (PWM_PIN(TFT_BACKLIGHT_PIN))
+        analogWrite(pin_t(TFT_BACKLIGHT_PIN), brightness);
+    #endif
+  }
+#endif
+
 #if HAS_LCD_MENU
 
   #include "../menu/menu.h"

Marlin/src/lcd/language/language_fr.h

   LSTR MSG_FILAMENT_LOAD                  = _UxGT("Charger mm");
   LSTR MSG_ADVANCE_K                      = _UxGT("Avance K");
   LSTR MSG_ADVANCE_K_E                    = _UxGT("Avance K *");
+  LSTR MSG_BRIGHTNESS                     = _UxGT("Luminosité LCD");
   LSTR MSG_CONTRAST                       = _UxGT("Contraste LCD");
   LSTR MSG_STORE_EEPROM                   = _UxGT("Enregistrer config.");
   LSTR MSG_LOAD_EEPROM                    = _UxGT("Charger config.");

Marlin/src/lcd/tft/touch.cpp

   }
   void Touch::wakeUp() {
     if (isSleeping()) {
-      #if PIN_EXISTS(TFT_BACKLIGHT)
+      #if HAS_LCD_BRIGHTNESS
+        ui._set_brightness();
+      #elif PIN_EXISTS(TFT_BACKLIGHT)
         WRITE(TFT_BACKLIGHT_PIN, HIGH);
       #endif
     }

Marlin/src/lcd/tft/ui_common.cpp

   cursor.set(0, 0);
 }
 
+#if HAS_LCD_BRIGHTNESS
+  void MarlinUI::_set_brightness() {
+    #if PIN_EXISTS(TFT_BACKLIGHT)
+      if (PWM_PIN(TFT_BACKLIGHT_PIN))
+        analogWrite(pin_t(TFT_BACKLIGHT_PIN), brightness);
+    #endif
+  }
+#endif
+
 #if ENABLED(TOUCH_SCREEN_CALIBRATION)
 
   void MarlinUI::touch_calibration_screen() {

Marlin/src/lcd/tft_io/tft_io.cpp

 #include "ili9341.h"
 #include "ili9328.h"
 
+#if HAS_LCD_BRIGHTNESS
+  #include "../marlinui.h"
+#endif
+
 #define DEBUG_OUT ENABLED(DEBUG_GRAPHICAL_TFT)
 #include "../../core/debug_out.h"
 
 
   #if PIN_EXISTS(TFT_BACKLIGHT)
     WRITE(TFT_BACKLIGHT_PIN, DISABLED(DELAYED_BACKLIGHT_INIT));
+    #if HAS_LCD_BRIGHTNESS && DISABLED(DELAYED_BACKLIGHT_INIT)
+      ui._set_brightness();
+    #endif
   #endif
 
   // io.Init();
         lcd_id = 0;
     }
   #else
-    #error Unsupported TFT driver
+    #error "Unsupported TFT driver"
   #endif
 
   #if PIN_EXISTS(TFT_BACKLIGHT) && ENABLED(DELAYED_BACKLIGHT_INIT)
     WRITE(TFT_BACKLIGHT_PIN, HIGH);
+    TERN_(HAS_LCD_BRIGHTNESS, ui._set_brightness());
   #endif
 }
 

Marlin/src/lcd/touch/touch_buttons.cpp

   }
   void TouchButtons::wakeUp() {
     if (isSleeping()) {
-      #if PIN_EXISTS(TFT_BACKLIGHT)
+      #if HAS_LCD_BRIGHTNESS
+        ui._set_brightness();
+      #elif PIN_EXISTS(TFT_BACKLIGHT)
         WRITE(TFT_BACKLIGHT_PIN, HIGH);
       #endif
     }

Marlin/src/pins/stm32f1/pins_LONGER3D_LK.h

 
   #define TFT_RESET_PIN                     PC4   // pin 33
   #define TFT_BACKLIGHT_PIN                 PD12  // pin 59
+  #define TFT_BACKLIGHT_PWM                 150   // Brightness with alt. TIM4 chan 1 (1-255)
 
   #define DOGLCD_MOSI                       -1    // Prevent auto-define by Conditionals_post.h
   #define DOGLCD_SCK                        -1
   #define TFT_BUFFER_SIZE                   3200
 #endif
 
+#if defined(TFT_BACKLIGHT_PWM) && !defined(MAPLE_STM32F1)
+  #define HAS_LCD_BRIGHTNESS 1
+  #define DEFAULT_LCD_BRIGHTNESS TFT_BACKLIGHT_PWM
+#endif
+
 #if ENABLED(SDIO_SUPPORT)
   #define SD_SS_PIN                         -1    // else SDSS set to PA4 in M43 (spi_pins.h)
 #endif