Added esp light sleep, still buggy state

app/src/CMakeLists.txt

@@ -6,6 +6,7 @@ idf_component_register(
 	"odroid/display.c"
 	"odroid/input.c"
 	"odroid/sdcard.c"
+	"odroid/sleep.c"
 	"text.c"
 
 	INCLUDE_DIRS

app/src/main.c

@@ -1,15 +1,16 @@
+#include <esp_log.h>
+#include <esp_timer.h>
+#include <freertos/FreeRTOS.h>
+#include <freertos/task.h>
+#include <string.h>
+#include "macros.h"
 #include "odroid/audio.h"
 #include "odroid/battery.h"
 #include "odroid/display.h"
 #include "odroid/input.h"
 #include "odroid/sdcard.h"
-#include "macros.h"
+#include "odroid/sleep.h"
 #include "text.h"
-#include <esp_log.h>
-#include <esp_timer.h>
-#include <freertos/FreeRTOS.h>
-#include <freertos/task.h>
-#include <string.h>
 
 #define ArraySize(array) sizeof((array)) / sizeof((array)[0])
 
@@ -24,6 +25,7 @@ static bool printInput = false;
 static bool enableLowFrameRate = true;
 
 static int64_t autoSleepModeMicroseconds = 10 * 1000000;
+static int64_t lightSleepMicroseconds = 30 * 1000000;
 
 static const char* LOG_TAG = "Main";
 static uint16_t gFramebuffer[LCD_WIDTH * LCD_HEIGHT];
@@ -195,6 +197,7 @@ void app_main(void)
 
 	Odroid_Input lastFrameInput = {0};
 
+	bool sleepMode = false;
 	bool backlightOn = true;
 	bool waitForSleepActivateRelease = false;
 
@@ -221,24 +224,28 @@ void app_main(void)
 			Odroid_PrintInputState(&input);
 
 		// Sleep mode
-		if (!backlightOn)
+		if (sleepMode)
 		{
-			if (!waitForSleepActivateRelease && hasInputsThisFrame)
+			// Try to save battery while still listening to inputs
+			while (Odroid_EnterLightSleep(lightSleepMicroseconds))
 			{
-				Odroid_BacklightInit();
-				backlightOn = true;
+				float batteryPercentage = Odroid_ReadBatteryLevelPercentage();
+				if (batteryPercentage < 15.f)
+					Odroid_EnableBatteryLight();
+				else
+					Odroid_DisableBatteryLight();
 			}
-			else
-			{
-				if (!input.b)
-					waitForSleepActivateRelease = false;
 
-				// Try to save battery while still listening to inputs
-				// TODO: Use the ESP sleep modes
-				vTaskDelay(250);
+			sleepMode = false;
+			timeSinceLastInputMicroSecs = esp_timer_get_time();
 
-				continue;
-			}
+			continue;
+		}
+
+		if (!sleepMode && !backlightOn)
+		{
+			Odroid_BacklightInit();
+			backlightOn = true;
 		}
 
 		if (input.a && !lastFrameInput.a)
@@ -276,12 +283,12 @@ void app_main(void)
 				// TODO: Tell LCD driver to enter sleep
 				// TODO: Use esp light sleep mode
 				Odroid_BacklightDeinit();
-				waitForSleepActivateRelease = true;
 			}
 			else
 				Odroid_BacklightInit();
 
 			backlightOn = !backlightOn;
+			sleepMode = !sleepMode;
 		}
 
 		// Movement

app/src/odroid/sleep.c

@@ -0,0 +1,64 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/time.h>
+#include <time.h>
+#include "driver/gpio.h"
+#include "driver/uart.h"
+#include "esp_log.h"
+#include "esp_sleep.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+
+// Button B
+#define BUTTON_GPIO_NUM_DEFAULT GPIO_NUM_32
+#define BUTTON_WAKEUP_LEVEL_DEFAULT 1
+
+// Returns whether button was pressed to wake
+// See Dependencies/esp-idf/examples/system/light_sleep/main/light_sleep_example_main.c
+bool Odroid_EnterLightSleep(int64_t timerAutoWakeupMicroSecs)
+{
+	esp_sleep_enable_timer_wakeup(timerAutoWakeupMicroSecs);
+
+	const int button_gpio_num = BUTTON_GPIO_NUM_DEFAULT;
+	const int wakeup_level = BUTTON_WAKEUP_LEVEL_DEFAULT;
+	gpio_config_t config = {.pin_bit_mask = BIT64(button_gpio_num), .mode = GPIO_MODE_INPUT};
+	ESP_ERROR_CHECK(gpio_config(&config));
+	gpio_wakeup_enable(button_gpio_num,
+	                   wakeup_level == 0 ? GPIO_INTR_LOW_LEVEL : GPIO_INTR_HIGH_LEVEL);
+	esp_sleep_enable_gpio_wakeup();
+
+	printf("Entering light sleep\n");
+	/* To make sure the complete line is printed before entering sleep mode, */
+	/* need to wait until UART TX FIFO is empty: */
+	uart_wait_tx_idle_polling(CONFIG_ESP_CONSOLE_UART_NUM);
+
+	/* Get timestamp before entering sleep */
+	int64_t t_before_us = esp_timer_get_time();
+
+	esp_light_sleep_start();
+
+	/* Get timestamp after waking up from sleep */
+	int64_t t_after_us = esp_timer_get_time();
+
+	/* Determine wake up reason */
+	const char* wakeup_reason;
+	esp_sleep_wakeup_cause_t cause = esp_sleep_get_wakeup_cause();
+	switch (cause)
+	{
+		case ESP_SLEEP_WAKEUP_TIMER:
+			wakeup_reason = "timer";
+			break;
+		case ESP_SLEEP_WAKEUP_GPIO:
+			wakeup_reason = "pin";
+			break;
+		default:
+			wakeup_reason = "other";
+			break;
+	}
+
+	printf("Returned from light sleep, reason: %s, t=%lld ms, slept for %lld ms\n", wakeup_reason,
+	       t_after_us / 1000, (t_after_us - t_before_us) / 1000);
+
+	return cause == ESP_SLEEP_WAKEUP_GPIO;
+}

app/src/odroid/sleep.h

@@ -0,0 +1,4 @@
+#pragma once
+
+// Returns whether button was pressed to wake
+bool Odroid_EnterLightSleep(int64_t timerAutoWakeupMicroSecs);