Cute brightness fade to avoid ugly startup :)

2 files changed, 23 insertions, 3 deletions

diff --git a/src/drivers/display.cpp b/src/drivers/display.cpp
index 7a49e02b..dd4cecb8 100644
--- a/src/drivers/display.cpp
+++ b/src/drivers/display.cpp
@@ -123,9 +123,11 @@ auto Display::Create(GpioExpander* expander,
                                     .hpoint = 0};
   ESP_ERROR_CHECK(ledc_channel_config(&led_channel));
 
-  ESP_ERROR_CHECK(ledc_set_duty(LEDC_LOW_SPEED_MODE, LEDC_CHANNEL_0, 4096));
+  ESP_ERROR_CHECK(ledc_set_duty(LEDC_LOW_SPEED_MODE, LEDC_CHANNEL_0, 0));
   ESP_ERROR_CHECK(ledc_update_duty(LEDC_LOW_SPEED_MODE, LEDC_CHANNEL_0));
 
+  ledc_fade_func_install(0);
+
   // Next, init the SPI device
   spi_device_interface_config_t spi_cfg = {
       .command_bits = 0,  // No command phase
@@ -180,9 +182,21 @@ auto Display::Create(GpioExpander* expander,
 Display::Display(GpioExpander* gpio, spi_device_handle_t handle)
     : gpio_(gpio),
       handle_(handle),
-      worker_task_(tasks::Worker::Start<tasks::Type::kUiFlush>()) {}
+      worker_task_(tasks::Worker::Start<tasks::Type::kUiFlush>()),
+      display_on_(false),
+      brightness_(4096) {}
+
+Display::~Display() {
+  ledc_fade_func_uninstall();
+}
 
-Display::~Display() {}
+auto Display::SetDisplayOn(bool enabled) -> void {
+  display_on_ = enabled;
+
+  int new_duty = display_on_ ? brightness_ : 0;
+  ledc_set_fade_with_time(LEDC_LOW_SPEED_MODE, LEDC_CHANNEL_0, new_duty, 250);
+  ledc_fade_start(LEDC_LOW_SPEED_MODE, LEDC_CHANNEL_0, LEDC_FADE_NO_WAIT);
+}
 
 void Display::SendInitialisationSequence(const uint8_t* data) {
   // Hold onto the bus for the entire sequence so that we're not interrupted
diff --git a/src/drivers/include/display.hpp b/src/drivers/include/display.hpp
index d2e0c14b..b394dd9e 100644
--- a/src/drivers/include/display.hpp
+++ b/src/drivers/include/display.hpp
@@ -6,6 +6,7 @@
 
 #pragma once
 
+#include <stdint.h>
 #include <cstdint>
 #include <memory>
 
@@ -35,6 +36,8 @@ class Display {
   Display(GpioExpander* gpio, spi_device_handle_t handle);
   ~Display();
 
+  auto SetDisplayOn(bool) -> void;
+
   /* Driver callback invoked by LVGL when there is new data to display. */
   void OnLvglFlush(lv_disp_drv_t* disp_drv,
                    const lv_area_t* area,
@@ -46,6 +49,9 @@ class Display {
 
   std::unique_ptr<tasks::Worker> worker_task_;
 
+  bool display_on_;
+  uint32_t brightness_;
+
   lv_disp_draw_buf_t buffers_;
   lv_disp_drv_t driver_;
   lv_disp_t* display_ = nullptr;