Merge pull request #95 from lvgl/feature/esp_lcd_backlight

LCD backlight controller

Author: tore-espressif

CMakeLists.txt

@@ -3,8 +3,7 @@ if(ESP_PLATFORM)
 file(GLOB SOURCES *.c)
 set(LVGL_INCLUDE_DIRS . lvgl_tft)
 list(APPEND SOURCES "lvgl_tft/disp_driver.c")
-
-#@todo add SimleInclude macro here
+list(APPEND SOURCES "lvgl_tft/esp_lcd_backlight.c")
 
 # Include only the source file of the selected
 # display controller.
@@ -79,11 +78,6 @@ if(CONFIG_LV_TOUCH_CONTROLLER)
     endif()
 endif()
 
-# Add backlight control to compilation only if it is selected in menuconfig
-if(CONFIG_LV_ENABLE_BACKLIGHT_CONTROL)
-    list(APPEND SOURCES "lvgl_tft/esp_lcd_backlight.c")
-endif()
-
 if(CONFIG_LV_I2C)
     list(APPEND SOURCES "lvgl_i2c/i2c_manager.c")
 endif()

README.md

@@ -7,6 +7,7 @@ For a ready to use ESP32 project take look at the [lv_port_esp32](https://github
 - [Supported indev controllers](#supported-indev-controllers)
 - [Support for predefined development kits](#support-for-predefined-development-kits)
 - [Thread-safe I2C with I2C Manager](#thread-safe-i2c-with-i2c-manager)
+- [Backlight control](#backlight-control)
 
 **NOTE:** You need to set the display horizontal and vertical size, color depth and
 swap of RGB565 color on the LVGL configuration menuconfig (it's not handled automatically).
@@ -79,3 +80,14 @@ talk to devices on the I2C ports without getting in each other's way. These driv
 use a built-in copy of I2C Manager to talk to the I2C port, but you can also use 
 the I2C Manager component itself and have others play nice with LVGL and vice-versa.
 [Click here](i2c_manager/README.md) for details.
+
+
+## Backlight control
+
+Control of LCD's backlight is provided by separate module that is independent from the display driver.
+Configuration of the backlight controller can be found in menuconfig `LVGL ESP Drivers -> LVGL TFT Display controller`.
+
+There are three modes of operation:
+1. Off - No backlight control
+2. Switch - Allows ON/OFF control
+3. PWM - Allows brightness control (by Pulse-Width-Modulated signal)

lvgl_tft/GC9A01.c

@@ -111,31 +111,14 @@ void GC9A01_init(void)
 
 	};
 
-#if GC9A01_BCKL == 15
-	gpio_config_t io_conf;
-    io_conf.intr_type = GPIO_PIN_INTR_DISABLE;
-    io_conf.mode = GPIO_MODE_OUTPUT;
-    io_conf.pin_bit_mask = GPIO_SEL_15;
-    io_conf.pull_down_en = GPIO_PULLDOWN_DISABLE;
-    io_conf.pull_up_en = GPIO_PULLUP_DISABLE;
-    gpio_config(&io_conf);
-#endif
-
 	//Initialize non-SPI GPIOs
-        gpio_pad_select_gpio(GC9A01_DC);
+    gpio_pad_select_gpio(GC9A01_DC);
 	gpio_set_direction(GC9A01_DC, GPIO_MODE_OUTPUT);
 
 #if GC9A01_USE_RST
-        gpio_pad_select_gpio(GC9A01_RST);
+    gpio_pad_select_gpio(GC9A01_RST);
 	gpio_set_direction(GC9A01_RST, GPIO_MODE_OUTPUT);
-#endif
-
-#if GC9A01_ENABLE_BACKLIGHT_CONTROL
-    gpio_pad_select_gpio(GC9A01_BCKL);
-    gpio_set_direction(GC9A01_BCKL, GPIO_MODE_OUTPUT);
-#endif
 
-#if GC9A01_USE_RST
 	//Reset the display
 	gpio_set_level(GC9A01_RST, 0);
 	vTaskDelay(100 / portTICK_RATE_MS);
@@ -156,8 +139,6 @@ void GC9A01_init(void)
 		cmd++;
 	}
 
-	GC9A01_enable_backlight(true);
-
 	GC9A01_set_orientation(CONFIG_LV_DISPLAY_ORIENTATION);
 
 #if GC9A01_INVERT_COLORS == 1
@@ -197,22 +178,6 @@ void GC9A01_flush(lv_disp_drv_t * drv, const lv_area_t * area, lv_color_t * colo
 	GC9A01_send_color((void*)color_map, size * 2);
 }
 
-void GC9A01_enable_backlight(bool backlight)
-{
-#if GC9A01_ENABLE_BACKLIGHT_CONTROL
-    ESP_LOGI(TAG, "%s backlight.", backlight ? "Enabling" : "Disabling");
-    uint32_t tmp = 0;
-
-#if (GC9A01_BCKL_ACTIVE_LVL==1)
-    tmp = backlight ? 1 : 0;
-#else
-    tmp = backlight ? 0 : 1;
-#endif
-
-    gpio_set_level(GC9A01_BCKL, tmp);
-#endif
-}
-
 void GC9A01_sleep_in()
 {
 	uint8_t data[] = {0x08};

lvgl_tft/GC9A01.h

@@ -25,19 +25,9 @@ extern "C" {
 /*********************
  *      DEFINES
  *********************/
-#define GC9A01_DC       CONFIG_LV_DISP_PIN_DC
-#define GC9A01_RST      CONFIG_LV_DISP_PIN_RST
-#define GC9A01_USE_RST  CONFIG_LV_DISP_USE_RST
-#define GC9A01_BCKL     CONFIG_LV_DISP_PIN_BCKL
-
-#define GC9A01_ENABLE_BACKLIGHT_CONTROL CONFIG_LV_ENABLE_BACKLIGHT_CONTROL
-
-#if CONFIG_LV_BACKLIGHT_ACTIVE_LVL
-  #define GC9A01_BCKL_ACTIVE_LVL 1
-#else
-  #define GC9A01_BCKL_ACTIVE_LVL 0
-#endif
-
+#define GC9A01_DC            CONFIG_LV_DISP_PIN_DC
+#define GC9A01_RST           CONFIG_LV_DISP_PIN_RST
+#define GC9A01_USE_RST       CONFIG_LV_DISP_USE_RST
 #define GC9A01_INVERT_COLORS CONFIG_LV_INVERT_COLORS
 
 /**********************
@@ -50,7 +40,6 @@ extern "C" {
 
 void GC9A01_init(void);
 void GC9A01_flush(lv_disp_drv_t * drv, const lv_area_t * area, lv_color_t * color_map);
-void GC9A01_enable_backlight(bool backlight);
 void GC9A01_sleep_in(void);
 void GC9A01_sleep_out(void);
 

lvgl_tft/Kconfig

@@ -910,51 +910,6 @@ menu "LVGL TFT Display controller"
             help
                 Configure the display Busy pin here.
 
-        config LV_ENABLE_BACKLIGHT_CONTROL
-            bool "Enable control of the display backlight by using an GPIO." if \
-                ( LV_PREDEFINED_DISPLAY_NONE && ! ( LV_TFT_DISPLAY_CONTROLLER_SH1107 || LV_TFT_DISPLAY_CONTROLLER_SSD1306 ) ) \
-                || LV_PREDEFINED_DISPLAY_RPI_MPI3501
-            default y if LV_PREDEFINED_DISPLAY_M5STACK
-            default n if LV_PREDEFINED_DISPLAY_M5CORE2
-            default y if LV_PREDEFINED_DISPLAY_WROVER4
-            default y if LV_PREDEFINED_DISPLAY_ERTFT0356
-            default y if LV_PREDEFINED_DISPLAY_TTGO
-            default y if LV_PREDEFINED_DISPLAY_TTGO_CAMERA_PLUS
-            default y if LV_PREDEFINED_DISPLAY_WT32_SC01
-            help
-                Enable controlling the display backlight using an GPIO
-
-        config LV_BACKLIGHT_ACTIVE_LVL
-            bool "Is backlight turn on with a HIGH (1) logic level?"
-            depends on LV_ENABLE_BACKLIGHT_CONTROL
-            default y if LV_PREDEFINED_DISPLAY_M5STACK
-            default y if LV_PREDEFINED_DISPLAY_ERTFT0356
-            default y if LV_PREDEFINED_DISPLAY_TTGO
-            default y if LV_PREDEFINED_DISPLAY_TTGO_CAMERA_PLUS
-            default y if LV_PREDEFINED_DISPLAY_WT32_SC01
-            help
-                Some backlights are turned on with a high signal, others held low.
-                If enabled, a value of 1 will be sent to the display to enable the backlight,
-                otherwise a 0 will be expected to enable it.
-
-        config LV_DISP_PIN_BCKL
-            int "GPIO for Backlight Control"
-            depends on LV_ENABLE_BACKLIGHT_CONTROL
-            default 23 if LV_PREDEFINED_PINS_38V1
-            default 26 if LV_PREDEFINED_PINS_38V4
-            default 32 if LV_PREDEFINED_DISPLAY_M5STACK
-            default 5 if LV_PREDEFINED_DISPLAY_WROVER4
-            default 2 if LV_PREDEFINED_DISPLAY_ADA_FEATHERWING
-            default 27 if LV_PREDEFINED_DISPLAY_ERTFT0356
-            default 0  if LV_PREDEFINED_PINS_TKOALA
-            default 4 if LV_PREDEFINED_DISPLAY_TTGO
-            default 2 if LV_PREDEFINED_DISPLAY_TTGO_CAMERA_PLUS
-            default 23 if LV_PREDEFINED_DISPLAY_WT32_SC01
-            default 27
-
-            help
-                Configure the display BCLK (LED) pin here.
-
     endmenu
 
     choice
@@ -965,19 +920,86 @@ menu "LVGL TFT Display controller"
         config LV_I2C_DISPLAY_PORT_0
             bool
             prompt "I2C port 0"
-            help 
+            help
                 I2C is shared peripheral managed by I2C Manager. In order to configure I2C Manager (pinout, etc.) see menu
                 Component config->I2C Port Settings.
 
         config LV_I2C_DISPLAY_PORT_1
             bool
             prompt "I2C port 1"
-            help 
+            help
                 I2C is shared peripheral managed by I2C Manager. In order to configure I2C Manager (pinout, etc.) see menu
                 Component config->I2C Port Settings.
 
     endchoice
 
+    choice
+        prompt "Backlight Control" if \
+            (! ( LV_TFT_DISPLAY_CONTROLLER_SH1107 || LV_TFT_DISPLAY_CONTROLLER_SSD1306 ) )
+        default LV_DISP_BACKLIGHT_SWITCH if LV_PREDEFINED_DISPLAY_M5STACK
+        default LV_DISP_BACKLIGHT_OFF if LV_PREDEFINED_DISPLAY_M5CORE2
+        default LV_DISP_BACKLIGHT_SWITCH if LV_PREDEFINED_DISPLAY_WROVER4
+        default LV_DISP_BACKLIGHT_SWITCH if LV_PREDEFINED_DISPLAY_ERTFT0356
+        default LV_DISP_BACKLIGHT_SWITCH if LV_PREDEFINED_DISPLAY_TTGO
+        default LV_DISP_BACKLIGHT_SWITCH if LV_PREDEFINED_DISPLAY_TTGO_CAMERA_PLUS
+        default LV_DISP_BACKLIGHT_SWITCH if LV_PREDEFINED_DISPLAY_WT32_SC01
+        default LV_DISP_BACKLIGHT_OFF
+
+        config LV_DISP_BACKLIGHT_OFF
+            bool
+            prompt "Not Used"
+            help
+                Display backlight is not controlled by this driver, must be hardwired in hardware.
+
+        config LV_DISP_BACKLIGHT_SWITCH
+            bool
+            prompt "Switch control"
+            help
+                Display backlight can be switched on or off.
+
+        config LV_DISP_BACKLIGHT_PWM
+            bool
+            prompt "PWM control"
+            help
+                Display backlight is controlled by pulse-width modulation, allowing brightness settings.
+
+    endchoice
+
+    config LV_BACKLIGHT_ACTIVE_LVL
+        bool "Is backlight turn on with a HIGH (1) logic level?" if \
+            ( LV_PREDEFINED_DISPLAY_NONE && ! ( LV_TFT_DISPLAY_CONTROLLER_SH1107 || LV_TFT_DISPLAY_CONTROLLER_SSD1306 ) ) \
+            || LV_PREDEFINED_DISPLAY_RPI_MPI3501
+        depends on !LV_DISP_BACKLIGHT_OFF
+        default y if LV_PREDEFINED_DISPLAY_M5STACK
+        default y if LV_PREDEFINED_DISPLAY_ERTFT0356
+        default y if LV_PREDEFINED_DISPLAY_TTGO
+        default y if LV_PREDEFINED_DISPLAY_TTGO_CAMERA_PLUS
+        default y if LV_PREDEFINED_DISPLAY_WT32_SC01
+        help
+            Some backlights are turned on with a high signal, others held low.
+            If enabled, a value of 1 will be sent to the display to enable the backlight,
+            otherwise a 0 will be expected to enable it.
+
+    config LV_DISP_PIN_BCKL
+        int "GPIO for Backlight Control" if \
+            ( LV_PREDEFINED_DISPLAY_NONE && ! ( LV_TFT_DISPLAY_CONTROLLER_SH1107 || LV_TFT_DISPLAY_CONTROLLER_SSD1306 ) ) \
+            || LV_PREDEFINED_DISPLAY_RPI_MPI3501
+        depends on !LV_DISP_BACKLIGHT_OFF
+        default 23 if LV_PREDEFINED_PINS_38V1
+        default 26 if LV_PREDEFINED_PINS_38V4
+        default 32 if LV_PREDEFINED_DISPLAY_M5STACK
+        default 5 if LV_PREDEFINED_DISPLAY_WROVER4
+        default 2 if LV_PREDEFINED_DISPLAY_ADA_FEATHERWING
+        default 27 if LV_PREDEFINED_DISPLAY_ERTFT0356
+        default 0  if LV_PREDEFINED_PINS_TKOALA
+        default 4 if LV_PREDEFINED_DISPLAY_TTGO
+        default 2 if LV_PREDEFINED_DISPLAY_TTGO_CAMERA_PLUS
+        default 23 if LV_PREDEFINED_DISPLAY_WT32_SC01
+        default 27
+
+        help
+            Configure the display BCLK (LED) pin here.
+
     config LV_I2C
         bool
         default y if LV_I2C_DISPLAY

lvgl_tft/disp_driver.c

@@ -4,8 +4,10 @@
 
 #include "disp_driver.h"
 #include "disp_spi.h"
+#include "esp_lcd_backlight.h"
+#include "sdkconfig.h"
 
-void disp_driver_init(void)
+void *disp_driver_init(void)
 {
 #if defined CONFIG_LV_TFT_DISPLAY_CONTROLLER_ILI9341
     ili9341_init();
@@ -42,6 +44,34 @@ void disp_driver_init(void)
 #elif defined CONFIG_LV_TFT_DISPLAY_CONTROLLER_ILI9163C
     ili9163c_init();
 #endif
+
+    // We still use menuconfig for these settings
+    // It will be set up during runtime in the future
+#ifndef CONFIG_LV_DISP_BACKLIGHT_OFF
+    const disp_backlight_config_t bckl_config = {
+        .gpio_num = CONFIG_LV_DISP_PIN_BCKL,
+#if defined CONFIG_LV_DISP_BACKLIGHT_PWM
+        .pwm_control = true,
+#else
+        .pwm_control = false,
+#endif
+#if defined CONFIG_LV_BACKLIGHT_ACTIVE_LVL
+        .output_invert = false, // Backlight on high
+#else
+        .output_invert = true, // Backlight on low
+#endif
+        .timer_idx = 0,
+        .channel_idx = 0 // @todo this prevents us from having two PWM controlled displays
+    };
+    const disp_backlight_config_t *bckl_config_p = &bckl_config;
+#else
+    const disp_backlight_config_t *bckl_config_p = NULL;
+#endif
+
+    disp_backlight_h bckl_handle = disp_backlight_new(bckl_config_p);
+    disp_backlight_set(bckl_handle, 100);
+
+    return bckl_handle;
 }
 
 void disp_driver_flush(lv_disp_drv_t * drv, const lv_area_t * area, lv_color_t * color_map)

lvgl_tft/disp_driver.h

@@ -67,7 +67,7 @@ extern "C" {
  **********************/
 
 /* Initialize display */
-void disp_driver_init(void);
+void *disp_driver_init(void);
 
 /* Display flush callback */
 void disp_driver_flush(lv_disp_drv_t * drv, const lv_area_t * area, lv_color_t * color_map);