Fixes and tests

This reverts commit 0d9cfe8e8b37a23d5f1c33758c8c625ebf738e76.

Buildscripts/devicetree-compiler/source/generator.py

@@ -52,7 +52,7 @@ def find_binding(compatible: str, bindings: list[Binding]) -> Binding:
             return binding
     return None
 
-def property_to_string(property: Property) -> str:
+def property_to_string(property: DeviceProperty) -> str:
     type = property.type
     if type == "value":
         return property.value
@@ -215,6 +215,8 @@ def generate_devicetree_h(filename: str):
         '''))
 
 def generate(output_path: str, items: list[object], bindings: list[Binding], verbose: bool):
+    if not os.path.exists(output_path):
+        os.makedirs(output_path)
     devicetree_c_filename = os.path.join(output_path, "devicetree.c")
     generate_devicetree_c(devicetree_c_filename, items, bindings, verbose)
     devicetree_h_filename = os.path.join(output_path, "devicetree.h")

Buildscripts/devicetree-compiler/source/models.py

@@ -11,7 +11,7 @@ class Device:
     devices: list
 
 @dataclass
-class Property:
+class DeviceProperty:
     name: str
     type: str
     value: object

Buildscripts/devicetree-compiler/source/transformer.py

@@ -26,7 +26,7 @@ class DtsTransformer(Transformer):
         for index, entry in enumerate(tokens):
             if index == 0:
                 identifier = entry.value
-            elif type(entry) is Property:
+            elif type(entry) is DeviceProperty:
                 properties.append(entry)
             elif type(entry) is Device:
                 devices.append(entry)
@@ -35,7 +35,7 @@ class DtsTransformer(Transformer):
         assert len(objects) == 2
         if not type(objects[1]) is PropertyValue:
             raise Exception(f"Object was not converted to PropertyValue: {objects[1]}")
-        return Property(objects[0], objects[1].type, objects[1].value)
+        return DeviceProperty(objects[0], objects[1].type, objects[1].value)
     def property_value(self, tokens: List):
         token = tokens[0]
         if type(token) is Token:

CMakeLists.txt

@@ -76,6 +76,7 @@ if (NOT DEFINED ENV{ESP_IDF_VERSION})
     add_subdirectory(TactilityCore)
     add_subdirectory(TactilityFreeRtos)
     add_subdirectory(TactilityKernel)
+    add_subdirectory(Drivers/PlatformPosix)
     add_subdirectory(Devices/simulator)
     add_subdirectory(Libraries/cJSON)
     add_subdirectory(Libraries/lv_screenshot)

Devices/btt-panda-touch/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/cyd-2432s024c/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/cyd-2432s028r/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/cyd-2432s028rv3/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/cyd-2432s032c/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/cyd-4848s040c/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/cyd-8048s043c/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/cyd-e32r28t/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/cyd-e32r32p/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/elecrow-crowpanel-advance-28/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/elecrow-crowpanel-advance-35/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/elecrow-crowpanel-advance-50/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/elecrow-crowpanel-basic-28/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/elecrow-crowpanel-basic-35/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/elecrow-crowpanel-basic-50/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/generic-esp32/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/generic-esp32c6/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/generic-esp32p4/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/generic-esp32s3/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+dts: ../placeholder.dts

Devices/lilygo-tlora-pager/CMakeLists.txt

@@ -3,5 +3,5 @@ file(GLOB_RECURSE SOURCE_FILES Source/*.c*)
 idf_component_register(
     SRCS ${SOURCE_FILES}
     INCLUDE_DIRS "Source"
-    REQUIRES Tactility esp_lcd ST7796 BQ25896 BQ27220 TCA8418 DRV2605 PwmBacklight driver esp_adc drivers-esp
+    REQUIRES Tactility esp_lcd ST7796 BQ25896 BQ27220 TCA8418 DRV2605 PwmBacklight driver esp_adc PlatformEsp32
 )

Devices/lilygo-tlora-pager/devicetree.yaml

@@ -1,4 +1,4 @@
 dependencies:
-  - Drivers/drivers-esp
+  - Drivers/PlatformEsp32
 bindings: ./
 dts: lilygo,tlora_pager.dts

Devices/simulator/devicetree.yaml

@@ -1,3 +1,4 @@
 dependencies:
   - TactilityKernel
+  - Drivers/PlatformPosix
 dts: ../placeholder.dts

Drivers/PlatformEsp32/CMakeLists.txt

@@ -0,0 +1,20 @@
+cmake_minimum_required(VERSION 3.20)
+
+file(GLOB_RECURSE SOURCES "Source/*.c**")
+
+if (DEFINED ENV{ESP_IDF_VERSION})
+
+    idf_component_register(
+        SRCS ${SOURCES}
+        INCLUDE_DIRS "Include/"
+        REQUIRES TactilityKernel driver
+    )
+
+else ()
+
+    add_library(PlatformEsp32 OBJECT)
+    target_sources(PlatformEsp32 PRIVATE ${SOURCES})
+    target_include_directories(PlatformEsp32 PUBLIC Include/)
+    target_link_libraries(PlatformEsp32 PUBLIC TactilityKernel)
+
+endif ()

Drivers/PlatformEsp32/Source/Esp32Gpio.cpp

@@ -46,7 +46,7 @@ static bool set_options(Device* device, gpio_pin_t pin, gpio_flags_t options) {
         .pull_down_en = (options & GPIO_PULL_DOWN) ? GPIO_PULLDOWN_ENABLE : GPIO_PULLDOWN_DISABLE,
         .intr_type = GPIO_INTERRUPT_FROM_OPTIONS(options),
 #if SOC_GPIO_SUPPORT_PIN_HYS_FILTER
-        .hys_ctrl_mode = GPIO_HYS_CTRL_EFUSE
+        .hys_ctrl_mode = GPIO_HYS_SOFT_DISABLE
 #endif
     };
 

Drivers/PlatformEsp32/Source/Esp32I2c.cpp

@@ -8,7 +8,7 @@
 #define TAG LOG_TAG(esp32_i2c)
 
 struct InternalData {
-    Mutex mutex {};
+    Mutex mutex { 0 };
 
     InternalData() {
         mutex_construct(&mutex);

Drivers/PlatformEsp32/devicetree.yaml

@@ -1,3 +1,3 @@
 dependencies:
   - TactilityKernel
-bindings: bindings
+bindings: Bindings

Drivers/PlatformPosix/CMakeLists.txt

@@ -0,0 +1,20 @@
+cmake_minimum_required(VERSION 3.20)
+
+file(GLOB_RECURSE SOURCES "Source/*.c**")
+
+if (DEFINED ENV{ESP_IDF_VERSION})
+
+    idf_component_register(
+        SRCS ${SOURCES}
+#        INCLUDE_DIRS "Include/"
+        REQUIRES TactilityKernel driver
+    )
+
+else ()
+
+    add_library(PlatformPosix OBJECT)
+    target_sources(PlatformPosix PRIVATE ${SOURCES})
+#    target_include_directories(PlatformPosix PUBLIC Include/)
+    target_link_libraries(PlatformPosix PUBLIC TactilityKernel)
+
+endif ()

Drivers/PlatformPosix/Source/Register.cpp

@@ -0,0 +1,9 @@
+#include <Tactility/Driver.h>
+
+extern "C" {
+
+extern void register_platform_drivers() {
+    /* Placeholder */
+}
+
+}

Drivers/PlatformPosix/devicetree.yaml

@@ -0,0 +1,2 @@
+dependencies:
+  - TactilityKernel

Drivers/drivers-esp/CMakeLists.txt

@@ -1,20 +0,0 @@
-cmake_minimum_required(VERSION 3.20)
-
-file(GLOB_RECURSE SOURCES "source/*.c**")
-
-if (DEFINED ENV{ESP_IDF_VERSION})
-
-    idf_component_register(
-        SRCS ${SOURCES}
-        INCLUDE_DIRS "include/"
-        REQUIRES TactilityKernel driver
-    )
-
-else ()
-
-    add_library(drivers-esp OBJECT)
-    target_sources(drivers-esp PRIVATE ${SOURCES})
-    target_include_directories(drivers-esp PUBLIC include/)
-    target_link_libraries(drivers-esp PUBLIC core)
-
-endif ()

Firmware/CMakeLists.txt

@@ -15,21 +15,23 @@ endif ()
 set(DEVICETREE_LOCATION "${CMAKE_SOURCE_DIR}/Devices/${TACTILITY_DEVICE_ID}")
 
 if (DEFINED ENV{ESP_IDF_VERSION})
+
     idf_component_register(
-        SRCS ${SOURCE_FILES}
-        REQUIRES Tactility TactilityC TactilityKernel drivers-esp ${TACTILITY_DEVICE_PROJECT}
+        SRCS ${SOURCE_FILES} "${CMAKE_SOURCE_DIR}/Firmware/Generated/devicetree.c"
+        REQUIRES Tactility TactilityC TactilityKernel PlatformEsp32 ${TACTILITY_DEVICE_PROJECT}
     )
 
 else ()
 
     add_executable(FirmwareSim ${SOURCE_FILES} "${CMAKE_SOURCE_DIR}/Firmware/Generated/devicetree.c")
-    target_link_libraries(FirmwareSim
-        PRIVATE Tactility
-        PRIVATE TactilityCore
-        PRIVATE TactilityFreeRtos
-        PRIVATE TactilityKernel
-        PRIVATE Simulator
-        PRIVATE SDL2::SDL2-static SDL2-static
+    target_link_libraries(FirmwareSim PRIVATE
+        Tactility
+        TactilityCore
+        TactilityFreeRtos
+        TactilityKernel
+        Simulator
+        PlatformPosix
+        SDL2::SDL2-static SDL2-static
     )
 
     add_definitions(-D_Nullable=)
@@ -51,6 +53,7 @@ add_custom_command(
 )
 add_custom_target(Generated DEPENDS "${CMAKE_SOURCE_DIR}/Firmware/Generated/devicetree.c")
 set_source_files_properties("${CMAKE_SOURCE_DIR}/Firmware/Generated/devicetree.c" PROPERTIES GENERATED TRUE)
+set_source_files_properties("${CMAKE_SOURCE_DIR}/Firmware/Generated/devicetree.h" PROPERTIES GENERATED TRUE)
 # Update target for generated code
 target_sources(${COMPONENT_LIB} PRIVATE "${CMAKE_SOURCE_DIR}/Firmware/Generated/devicetree.c")
 target_include_directories(${COMPONENT_LIB} PRIVATE "${CMAKE_SOURCE_DIR}/Firmware/Generated")

TactilityCore/Include/Tactility/LoggerAdapterGeneric.h

@@ -29,7 +29,7 @@ static const LoggerAdapter genericLoggerAdapter = [](LogLevel level, const char*
     constexpr auto COLOR_GREY = "\033[37m";
     std::stringstream buffer;
     buffer << COLOR_GREY << getLogTimestamp() << ' ' << toTagColour(level) << toPrefix(level) << COLOR_GREY << " [" << COLOR_RESET << tag << COLOR_GREY << "] " << toMessageColour(level) << message << COLOR_RESET << std::endl;
-    printf(buffer.str().c_str());
+    printf("%s", buffer.str().c_str());
 };
 
 }

TactilityKernel/CMakeLists.txt

@@ -1,18 +1,18 @@
 cmake_minimum_required(VERSION 3.20)
 
-file(GLOB_RECURSE SOURCES "source/*.c**")
+file(GLOB_RECURSE SOURCES "Source/*.c**")
 
 if (DEFINED ENV{ESP_IDF_VERSION})
 
     idf_component_register(
         SRCS ${SOURCES}
-        INCLUDE_DIRS "include/"
+        INCLUDE_DIRS "Include/"
     )
 
 else ()
 
-    add_library(core OBJECT ${SOURCES})
-    target_include_directories(core PUBLIC include/)
-    target_link_libraries(core PUBLIC freertos_kernel)
+    add_library(TactilityKernel OBJECT ${SOURCES})
+    target_include_directories(TactilityKernel PUBLIC Include/)
+    target_link_libraries(TactilityKernel PUBLIC freertos_kernel)
 
 endif ()

TactilityKernel/Include/Tactility/Device.h

@@ -154,8 +154,21 @@ static inline void device_unlock(struct Device* device) {
 static inline const struct DeviceType* device_get_type(struct Device* device) {
     return device->internal.driver->device_type;
 }
+/**
+ * Iterate through all the known devices
+ * @param callback_context the parameter to pass to the callback. NULL is valid.
+ * @param on_device the function to call for each filtered device. return true to continue iterating or false to stop.
+ */
+void for_each_device(void* callback_context, bool(*on_device)(struct Device* device, void* context));
 
-    /**
+/**
+ * Iterate through all the child devices of the specified device
+ * @param callback_context the parameter to pass to the callback. NULL is valid.
+ * @param on_device the function to call for each filtered device. return true to continue iterating or false to stop.
+ */
+void for_each_device_child(struct Device* device, void* callback_context, bool(*on_device)(struct Device* device, void* context));
+
+/**
  * Iterate through all the known devices of a specific type
  * @param type the type to filter
  * @param callback_context the parameter to pass to the callback. NULL is valid.

TactilityKernel/Include/Tactility/FreeRTOS/FreeRTOS.h

@@ -5,3 +5,6 @@
 #else
 #include <FreeRTOS.h>
 #endif
+
+// Custom port compatibility definitins, mainly for PC compatibility
+#include "port.h"

TactilityKernel/Include/Tactility/FreeRTOS/event_groups.h

@@ -1,10 +1,10 @@
 #pragma once
 
+#include "FreeRTOS.h"
+
 #ifdef ESP_PLATFORM
-#include <freertos/FreeRTOS.h>
 #include <freertos/event_groups.h>
 #else
-#include <FreeRTOS.h>
 #include <event_groups.h>
 #endif
 

TactilityKernel/Include/Tactility/FreeRTOS/port.h

@@ -4,4 +4,5 @@
 
 #ifndef ESP_PLATFORM
 #define xPortInIsrContext(x) (false)
+#define vPortAssertIfInISR()
 #endif

TactilityKernel/Include/Tactility/FreeRTOS/queue.h

@@ -1,10 +1,10 @@
 #pragma once
 
+#include "FreeRTOS.h"
+
 #ifdef ESP_PLATFORM
-#include <freertos/FreeRTOS.h>
 #include <freertos/queue.h>
 #else
-#include <FreeRTOS.h>
 #include <queue.h>
 #endif
 

TactilityKernel/Include/Tactility/FreeRTOS/semphr.h

@@ -1,9 +1,9 @@
 #pragma once
 
+#include "FreeRTOS.h"
+
 #ifdef ESP_PLATFORM
-#include <freertos/FreeRTOS.h>
 #include <freertos/semphr.h>
 #else
-#include <FreeRTOS.h>
 #include <semphr.h>
 #endif

TactilityKernel/Include/Tactility/FreeRTOS/task.h

@@ -1,10 +1,10 @@
 #pragma once
 
+#include "FreeRTOS.h"
+
 #ifdef ESP_PLATFORM
-#include <freertos/FreeRTOS.h>
 #include <freertos/task.h>
 #else
-#include <FreeRTOS.h>
 #include <task.h>
 #endif
 

TactilityKernel/Include/Tactility/FreeRTOS/timers.h

@@ -1,9 +1,9 @@
 #pragma once
 
+#include "FreeRTOS.h"
+
 #ifdef ESP_PLATFORM
-#include <freertos/FreeRTOS.h>
 #include <freertos/timers.h>
 #else
-#include <FreeRTOS.h>
 #include <timers.h>
 #endif

TactilityKernel/Include/Tactility/concurrent/Mutex.h

@@ -2,6 +2,7 @@
 
 #include <Tactility/FreeRTOS/semphr.h>
 #include <assert.h>
+#include <stdbool.h>
 
 #ifdef __cplusplus
 extern "C" {

TactilityKernel/Include/Tactility/concurrent/RecursiveMutex.h

@@ -1,8 +1,6 @@
 #pragma once
 
-#include "freertos/semphr.h"
-
-
+#include <stdbool.h>
 #include <Tactility/FreeRTOS/semphr.h>
 
 #ifdef __cplusplus
@@ -20,6 +18,7 @@ inline static void recursive_mutex_construct(struct RecursiveMutex* mutex) {
 inline static void recursive_mutex_destruct(struct RecursiveMutex* mutex) {
     assert(mutex != NULL);
     assert(mutex->handle != NULL);
+    vPortAssertIfInISR();
     vSemaphoreDelete(mutex->handle);
     mutex->handle = NULL;
 }

TactilityKernel/Source/Device.cpp

@@ -3,7 +3,7 @@
 #include <Tactility/Driver.h>
 #include <Tactility/Log.h>
 
-#include <algorithm>
+#include <ranges>
 #include <cassert>
 #include <cstring>
 #include <sys/errno.h>
@@ -17,7 +17,7 @@ struct DeviceData {
 
 struct DeviceLedger {
     std::vector<Device*> devices;
-    Mutex mutex {};
+    Mutex mutex { 0 };
 
     DeviceLedger() {
         mutex_construct(&mutex);
@@ -54,7 +54,8 @@ int device_destruct(Device* device) {
 /** Add a child to the list of children */
 static void device_add_child(struct Device* device, struct Device* child) {
     device_lock(device);
-    get_device_data(device)->children.push_back(device);
+    assert(device->internal.state.added);
+    get_device_data(device)->children.push_back(child);
     device_unlock(device);
 }
 
@@ -175,6 +176,25 @@ void device_set_parent(Device* device, Device* parent) {
     device->parent = parent;
 }
 
+void for_each_device(void* callback_context, bool(*on_device)(Device* device, void* context)) {
+    ledger_lock();
+    for (auto* device : ledger.devices) {
+        if (!on_device(device, callback_context)) {
+            break;
+        }
+    }
+    ledger_unlock()
+}
+
+void for_each_device_child(Device* device, void* callback_context, bool(*on_device)(struct Device* device, void* context)) {
+    auto* data = get_device_data(device);
+    for (auto* child_device : data->children) {
+        if (!on_device(child_device, callback_context)) {
+            break;
+        }
+    }
+}
+
 void for_each_device_of_type(const DeviceType* type, void* callback_context, bool(*on_device)(Device* device, void* context)) {
     ledger_lock();
     for (auto* device : ledger.devices) {

TactilityKernel/Source/Driver.cpp

@@ -1,4 +1,5 @@
-#include <sys/errno.h>
+#include <cstring>
+#include <ranges>
 #include <vector>
 
 #include <Tactility/concurrent/Mutex.h>
@@ -10,7 +11,7 @@
 #define TAG LOG_TAG(driver)
 
 struct DriverInternalData {
-    Mutex mutex {};
+    Mutex mutex { 0 };
     int use_count = 0;
 
     DriverInternalData() {
@@ -24,7 +25,7 @@ struct DriverInternalData {
 
 struct DriverLedger {
     std::vector<Driver*> drivers = {};
-    Mutex mutex {};
+    Mutex mutex { 0 };
 
     DriverLedger() {
         mutex_construct(&mutex);

TactilityKernel/devicetree.yaml

@@ -1 +1 @@
-bindings: bindings
+bindings: Bindings

Tests/CMakeLists.txt

@@ -5,9 +5,11 @@ set(DOCTESTINC ${PROJECT_SOURCE_DIR}/Include)
 enable_testing()
 add_subdirectory(TactilityCore)
 add_subdirectory(TactilityFreeRtos)
+add_subdirectory(TactilityKernel)
 add_subdirectory(Tactility)
 
 add_custom_target(build-tests)
 add_dependencies(build-tests TactilityCoreTests)
 add_dependencies(build-tests TactilityFreeRtosTests)
 add_dependencies(build-tests TactilityTests)
+add_dependencies(build-tests TactilityKernelTests)

Tests/TactilityKernel/CMakeLists.txt

@@ -0,0 +1,14 @@
+project(TactilityCoreTests)
+
+enable_language(C CXX ASM)
+
+set(CMAKE_CXX_COMPILER g++)
+
+file(GLOB_RECURSE TEST_SOURCES ${PROJECT_SOURCE_DIR}/*.cpp)
+add_executable(TactilityKernelTests EXCLUDE_FROM_ALL ${TEST_SOURCES})
+
+target_include_directories(TactilityKernelTests PRIVATE ${DOCTESTINC})
+
+add_test(NAME TactilityKernelTests COMMAND TactilityKernelTests)
+
+target_link_libraries(TactilityKernelTests PUBLIC TactilityKernel)

Tests/TactilityKernel/DeviceTest.cpp

@@ -0,0 +1,92 @@
+#include "doctest.h"
+
+#include <string.h>
+#include <vector>
+
+#include <Tactility/Device.h>
+
+TEST_CASE("device_construct and device_destruct should set and unset the correct fields") {
+    Device device = { 0 };
+
+    device_construct(&device);
+
+    CHECK_NE(device.internal.data, nullptr);
+    CHECK_NE(device.internal.mutex.handle, nullptr);
+
+    device_destruct(&device);
+
+    CHECK_EQ(device.internal.data, nullptr);
+    CHECK_EQ(device.internal.mutex.handle, nullptr);
+
+    Device comparison_device = { 0 };
+    comparison_device.internal.data = device.internal.data;
+    comparison_device.internal.mutex.handle = device.internal.mutex.handle;
+
+    // Check that no other data was set
+    CHECK_EQ(memcmp(&device, &comparison_device, sizeof(struct Device)), 0);
+}
+
+TEST_CASE("device_add should make the device discoverable") {
+    Device device = { 0 };
+    device_construct(&device);
+    device_add(&device);
+
+    // Gather all devices
+    std::vector<Device*> devices;
+    for_each_device(&devices, [](auto* device, auto* context) {
+        auto* devices_ptr = (std::vector<Device*>*)context;
+        devices_ptr->push_back(device);
+        return true;
+    });
+
+    CHECK_EQ(devices.size(), 1);
+    CHECK_EQ(devices[0], &device);
+
+    device_remove(&device);
+    device_destruct(&device);
+}
+
+TEST_CASE("device_add should add the device to its parent") {
+    Device parent = { 0 };
+
+    Device child = {
+        .name = nullptr,
+        .config = nullptr,
+        .parent = &parent
+    };
+
+    device_construct(&parent);
+    device_add(&parent);
+
+    device_construct(&child);
+    device_add(&child);
+
+    // Gather all child devices
+    std::vector<Device*> children;
+    for_each_device_child(&parent, &children, [](auto* child_device, auto* context) {
+        auto* children_ptr = (std::vector<Device*>*)context;
+        children_ptr->push_back(child_device);
+        return true;
+    });
+
+    CHECK_EQ(children.size(), 1);
+    CHECK_EQ(children[0], &child);
+
+    device_remove(&child);
+    device_destruct(&child);
+
+    device_remove(&parent);
+    device_destruct(&parent);
+}
+
+TEST_CASE("device_add should set the state to 'added'") {
+    Device device = { 0 };
+    device_construct(&device);
+
+    CHECK_EQ(device.internal.state.added, false);
+    device_add(&device);
+    CHECK_EQ(device.internal.state.added, true);
+
+    device_remove(&device);
+    device_destruct(&device);
+}

Tests/TactilityKernel/DriverTest.cpp

@@ -0,0 +1,6 @@
+#include "doctest.h"
+#include <Tactility/Driver.h>
+
+TEST_CASE("placeholder driver test") {
+    // TODO: Implement
+}

Tests/TactilityKernel/Main.cpp

@@ -0,0 +1,59 @@
+#define DOCTEST_CONFIG_IMPLEMENT
+#include "doctest.h"
+#include <cassert>
+
+#include <Tactility/FreeRTOS/task.h>
+
+typedef struct {
+    int argc;
+    char** argv;
+    int result;
+} TestTaskData;
+
+void test_task(void* parameter) {
+    auto* data = (TestTaskData*)parameter;
+
+    doctest::Context context;
+
+    context.applyCommandLine(data->argc, data->argv);
+
+    // overrides
+    context.setOption("no-breaks", true); // don't break in the debugger when assertions fail
+
+    data->result = context.run();
+
+    if (context.shouldExit()) { // important - query flags (and --exit) rely on the user doing this
+        vTaskEndScheduler();
+    }
+
+    vTaskDelete(nullptr);
+}
+
+int main(int argc, char** argv) {
+    TestTaskData data = {
+        .argc = argc,
+        .argv = argv,
+        .result = 0
+    };
+
+    BaseType_t task_result = xTaskCreate(
+        test_task,
+        "test_task",
+        8192,
+        &data,
+        1,
+        nullptr
+    );
+    assert(task_result == pdPASS);
+
+    vTaskStartScheduler();
+
+    return data.result;
+}
+
+extern "C" {
+    // Required for FreeRTOS
+    void vAssertCalled(unsigned long line, const char* const file) {
+        __assert_fail("assert failed", file, line, "");
+    }
+}

Tests/TactilityKernel/TestFile.h

@@ -0,0 +1,42 @@
+#pragma once
+
+#include "doctest.h"
+#include <unistd.h>
+
+#include <Tactility/file/File.h>
+
+/**
+ * A class for creating test files that can automatically clean themselves up.
+ */
+class TestFile {
+    const char* path;
+    bool autoClean;
+
+public:
+
+    TestFile(const char* path, bool autoClean = true) : path(path), autoClean(autoClean) {
+        if (autoClean && exists()) {
+            remove();
+        }
+    }
+
+    ~TestFile() {
+        if (autoClean && exists()) {
+            remove();
+        }
+    }
+
+    const char* getPath() const { return path; }
+
+    void writeData(const char* data) const {
+        CHECK_EQ(tt::file::writeString(path, data), true);
+    }
+
+    bool exists() const {
+        return access(path, F_OK) == 0;
+    }
+
+    void remove() const {
+        ::remove(path);
+    }
+};