Create hal-device module, fix GPIO, fix tests, fix TactilityC (#471)

* **New Features**
  * Added a HAL device module providing device enumeration, type queries and a HAL↔kernel bridge.

* **Improvements**
  * Integrated HAL module into startup; standardized module names, includes and lifecycle logging; safer file append behavior; broader build support.

* **API Changes**
  * Driver lifecycle now uses explicit add/remove semantics; C and HAL device type/lookup APIs clarified.

* **Chores**
  * Added module README and Apache‑2.0 license; updated build configuration to include the new module.

* **Fixes**
  * Updated tests and object file handling to behave correctly.

CMakeLists.txt

@@ -32,6 +32,7 @@ if (DEFINED ENV{ESP_IDF_VERSION})
         "Firmware"
         "Devices/${TACTILITY_DEVICE_PROJECT}"
         "Drivers"
+        "Modules"
         "Platforms/PlatformEsp32"
         "TactilityKernel"
         "Tactility"
@@ -84,6 +85,7 @@ if (NOT DEFINED ENV{ESP_IDF_VERSION})
     add_subdirectory(Libraries/QRCode)
     add_subdirectory(Libraries/minitar)
     add_subdirectory(Libraries/minmea)
+    add_subdirectory(Modules/hal-device)
 
     # FreeRTOS
     set(FREERTOS_CONFIG_FILE_DIRECTORY ${PROJECT_SOURCE_DIR}/Devices/simulator/Source CACHE STRING "")

Devices/heltec-wifi-lora-32-v3/Source/Configuration.cpp

@@ -36,7 +36,7 @@ static bool initBoot() {
 
 using namespace tt::hal;
 
-static std::vector<std::shared_ptr<Device>> createDevices() {
+static std::vector<std::shared_ptr<tt::hal::Device>> createDevices() {
     return {
         createPower(),
         ButtonControl::createOneButtonControl(0),

Devices/lilygo-tdeck/Source/Configuration.cpp

@@ -12,7 +12,7 @@ bool initBoot();
 
 using namespace tt::hal;
 
-static std::vector<std::shared_ptr<Device>> createDevices() {
+static std::vector<std::shared_ptr<tt::hal::Device>> createDevices() {
     return {
         createPower(),
         createDisplay(),

Devices/lilygo-tdeck/Source/devices/KeyboardBacklight.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <Tactility/hal/Device.h>
+#include <tactility/hal/Device.h>
 #include <Tactility/TactilityCore.h>
 
 class KeyboardBacklightDevice final : public tt::hal::Device {

Devices/lilygo-tdeck/Source/devices/TdeckKeyboard.cpp

@@ -5,7 +5,7 @@
 #include <Tactility/settings/KeyboardSettings.h>
 #include <Tactility/settings/DisplaySettings.h>
 #include <Tactility/hal/display/DisplayDevice.h>
-#include <Tactility/hal/Device.h>
+#include <tactility/hal/Device.h>
 #include <Tactility/Logger.h>
 #include <KeyboardBacklight/KeyboardBacklight.h>
 

Devices/lilygo-tdeck/Source/devices/TrackballDevice.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <Tactility/hal/Device.h>
+#include <tactility/hal/Device.h>
 #include <lvgl.h>
 
 class TrackballDevice : public tt::hal::Device {

Devices/lilygo-tdisplay-s3/Source/Configuration.cpp

@@ -9,7 +9,7 @@ bool initBoot();
 
 using namespace tt::hal;
 
-static std::vector<std::shared_ptr<Device>> createDevices() {
+static std::vector<std::shared_ptr<tt::hal::Device>> createDevices() {
     return {
         createPower(),
         createDisplay(),

Devices/lilygo-tdisplay/Source/Configuration.cpp

@@ -11,7 +11,7 @@ static bool initBoot() {
     return driver::pwmbacklight::init(LCD_PIN_BACKLIGHT);
 }
 
-static std::vector<std::shared_ptr<Device>> createDevices() {
+static std::vector<std::shared_ptr<tt::hal::Device>> createDevices() {
     return {
         createDisplay(),
         ButtonControl::createTwoButtonControl(35, 0)

Devices/lilygo-tdongle-s3/Source/Configuration.cpp

@@ -10,7 +10,7 @@ bool initBoot();
 
 using namespace tt::hal;
 
-static std::vector<std::shared_ptr<Device>> createDevices() {
+static std::vector<std::shared_ptr<tt::hal::Device>> createDevices() {
     return {
         createDisplay(),
         createSdCard()

Devices/lilygo-tlora-pager/Source/Configuration.cpp

@@ -22,7 +22,7 @@ static DeviceVector createDevices() {
     auto tca8418 = std::make_shared<Tca8418>(I2C_NUM_0);
     auto keyboard = std::make_shared<TpagerKeyboard>(tca8418);
 
-    return std::vector<std::shared_ptr<Device>> {
+    return std::vector<std::shared_ptr<tt::hal::Device>> {
         tca8418,
         std::make_shared<Bq25896>(I2C_NUM_0),
         bq27220,

Devices/lilygo-tlora-pager/Source/module.cpp

@@ -9,14 +9,14 @@ extern Driver tlora_pager_driver;
 static error_t start() {
     /* We crash when construct fails, because if a single driver fails to construct,
      * there is no guarantee that the previously constructed drivers can be destroyed */
-    check(driver_construct(&tlora_pager_driver) == ERROR_NONE);
+    check(driver_construct_add(&tlora_pager_driver) == ERROR_NONE);
     return ERROR_NONE;
 }
 
 static error_t stop() {
     /* We crash when destruct fails, because if a single driver fails to destruct,
      * there is no guarantee that the previously destroyed drivers can be recovered */
-    check(driver_destruct(&tlora_pager_driver) == ERROR_NONE);
+    check(driver_remove_destruct(&tlora_pager_driver) == ERROR_NONE);
     return ERROR_NONE;
 }
 

Devices/simulator/Source/Simulator.cpp

@@ -28,7 +28,7 @@ static void deinitPower() {
 #endif
 }
 
-static std::vector<std::shared_ptr<Device>> createDevices() {
+static std::vector<std::shared_ptr<tt::hal::Device>> createDevices() {
     return {
         std::make_shared<SdlDisplay>(),
         std::make_shared<SdlKeyboard>(),

Devices/waveshare-s3-touch-lcd-147/Source/Configuration.cpp

@@ -10,7 +10,7 @@ bool initBoot();
 
 using namespace tt::hal;
 
-static std::vector<std::shared_ptr<Device>> createDevices() {
+static std::vector<std::shared_ptr<tt::hal::Device>> createDevices() {
     return {
         createDisplay(),
         createSdCard()

Drivers/XPT2046/Source/Xpt2046Power.cpp

@@ -2,7 +2,7 @@
 #include "Xpt2046Touch.h"
 
 #include <Tactility/Logger.h>
-#include <Tactility/hal/Device.h>
+#include <tactility/hal/Device.h>
 
 static const auto LOGGER = tt::Logger("Xpt2046Power");
 

Firmware/CMakeLists.txt

@@ -36,6 +36,7 @@ else ()
         TactilityCore
         TactilityFreeRtos
         TactilityKernel
+        hal-device
         Simulator
         PlatformPosix
         SDL2::SDL2-static SDL2-static

Modules/hal-device/CMakeLists.txt

@@ -0,0 +1,46 @@
+cmake_minimum_required(VERSION 3.20)
+
+if (DEFINED ENV{ESP_IDF_VERSION})
+    file(GLOB_RECURSE SOURCE_FILES Source/*.c*)
+
+    list(APPEND REQUIRES_LIST
+        TactilityKernel
+        TactilityCore
+        TactilityFreeRtos
+    )
+
+    idf_component_register(
+        SRCS ${SOURCE_FILES}
+        INCLUDE_DIRS "Include/"
+        REQUIRES ${REQUIRES_LIST}
+    )
+
+    if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
+        target_compile_options(${COMPONENT_LIB} PUBLIC -Wno-unused-variable)
+    endif ()
+
+else ()
+
+    file(GLOB_RECURSE SOURCES "Source/*.c*")
+
+    add_library(hal-device OBJECT)
+
+    target_sources(hal-device PRIVATE ${SOURCES})
+
+    target_include_directories(hal-device
+        PRIVATE Private/
+        PUBLIC Include/
+    )
+
+    add_definitions(-D_Nullable=)
+    add_definitions(-D_Nonnull=)
+
+    target_link_libraries(hal-device PUBLIC
+        TactilityFreeRtos
+        TactilityCore
+        TactilityKernel
+        freertos_kernel
+    )
+    
+endif ()
+

Modules/hal-device/Include/tactility/drivers/hal_device.h

@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+enum class HalDeviceType {
+    HAL_DEVICE_TYPE_I2C,
+    HAL_DEVICE_TYPE_DISPLAY,
+    HAL_DEVICE_TYPE_TOUCH,
+    HAL_DEVICE_TYPE_SDCARD,
+    HAL_DEVICE_TYPE_KEYBOARD,
+    HAL_DEVICE_TYPE_ENCODER,
+    HAL_DEVICE_TYPE_POWER,
+    HAL_DEVICE_TYPE_GPS,
+    HAL_DEVICE_TYPE_OTHER
+};
+
+HalDeviceType hal_device_get_type(struct Device* device);
+
+void hal_device_for_each_of_type(HalDeviceType type, void* context, bool(*onDevice)(struct Device* device, void* context));
+
+extern const struct DeviceType HAL_DEVICE_TYPE;
+
+#ifdef __cplusplus
+}
+#endif

Modules/hal-device/Include/tactility/drivers/hal_device.hpp

@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include "hal_device.h"
+
+#include <memory>
+#include <tactility/hal/Device.h>
+
+namespace tt::hal {
+
+/**
+ * @brief Get a tt::hal::Device object from a Kernel device.
+ * @warning The input device must be of type HAL_DEVICE_TYPE
+ * @param kernelDevice The kernel device
+ * @return std::shared_ptr<Device>
+ */
+std::shared_ptr<Device> hal_device_get_device(::Device* kernelDevice);
+
+void hal_device_set_device(::Device* kernelDevice, std::shared_ptr<Device> halDevice);
+
+}

Modules/hal-device/Include/tactility/hal/Device.h

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: Apache-2.0
 #pragma once
 
 #include <functional>
@@ -7,6 +8,10 @@
 #include <vector>
 #include <cassert>
 
+#include <tactility/device.h>
+
+typedef ::Device KernelDevice;
+
 namespace tt::hal {
 /** Base class for HAL-related devices. */
 class Device {
@@ -27,9 +32,19 @@ public:
 
     typedef uint32_t Id;
 
+    struct KernelDeviceHolder {
+        const std::string name;
+        std::shared_ptr<KernelDevice> device = std::make_shared<KernelDevice>();
+
+        explicit KernelDeviceHolder(std::string name) : name(name) {
+            device->name = this->name.c_str();
+        }
+    };
+
 private:
 
     Id id;
+    std::shared_ptr<KernelDeviceHolder> kernelDeviceHolder;
 
 public:
 
@@ -49,6 +64,10 @@ public:
      * e.g. "USB charging controller with I2C interface."
      */
     virtual std::string getDescription() const = 0;
+
+    void setKernelDeviceHolder(std::shared_ptr<KernelDeviceHolder> kernelDeviceHolder) { this->kernelDeviceHolder = kernelDeviceHolder; }
+
+    std::shared_ptr<KernelDeviceHolder> getKernelDeviceHolder() const { return kernelDeviceHolder; }
 };
 
 /**
@@ -92,7 +111,7 @@ std::vector<std::shared_ptr<DeviceType>> findDevices(Device::Type type) {
             assert(target_device != nullptr);
             result.push_back(target_device);
         }
-        return std::move(result);
+        return result;
     }
 }
 

Modules/hal-device/Include/tactility/hal_device_module.h

@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern struct Module hal_device_module;
+
+#ifdef __cplusplus
+}
+#endif

Modules/hal-device/LICENSE-Apache-2.0.md

@@ -0,0 +1,195 @@
+Apache License
+==============
+
+_Version 2.0, January 2004_  
+_&lt;<http://www.apache.org/licenses/>&gt;_
+
+### Terms and Conditions for use, reproduction, and distribution
+
+#### 1. Definitions
+
+“License” shall mean the terms and conditions for use, reproduction, and
+distribution as defined by Sections 1 through 9 of this document.
+
+“Licensor” shall mean the copyright owner or entity authorized by the copyright
+owner that is granting the License.
+
+“Legal Entity” shall mean the union of the acting entity and all other entities
+that control, are controlled by, or are under common control with that entity.
+For the purposes of this definition, “control” means **(i)** the power, direct or
+indirect, to cause the direction or management of such entity, whether by
+contract or otherwise, or **(ii)** ownership of fifty percent (50%) or more of the
+outstanding shares, or **(iii)** beneficial ownership of such entity.
+
+“You” (or “Your”) shall mean an individual or Legal Entity exercising
+permissions granted by this License.
+
+“Source” form shall mean the preferred form for making modifications, including
+but not limited to software source code, documentation source, and configuration
+files.
+
+“Object” form shall mean any form resulting from mechanical transformation or
+translation of a Source form, including but not limited to compiled object code,
+generated documentation, and conversions to other media types.
+
+“Work” shall mean the work of authorship, whether in Source or Object form, made
+available under the License, as indicated by a copyright notice that is included
+in or attached to the work (an example is provided in the Appendix below).
+
+“Derivative Works” shall mean any work, whether in Source or Object form, that
+is based on (or derived from) the Work and for which the editorial revisions,
+annotations, elaborations, or other modifications represent, as a whole, an
+original work of authorship. For the purposes of this License, Derivative Works
+shall not include works that remain separable from, or merely link (or bind by
+name) to the interfaces of, the Work and Derivative Works thereof.
+
+“Contribution” shall mean any work of authorship, including the original version
+of the Work and any modifications or additions to that Work or Derivative Works
+thereof, that is intentionally submitted to Licensor for inclusion in the Work
+by the copyright owner or by an individual or Legal Entity authorized to submit
+on behalf of the copyright owner. For the purposes of this definition,
+“submitted” means any form of electronic, verbal, or written communication sent
+to the Licensor or its representatives, including but not limited to
+communication on electronic mailing lists, source code control systems, and
+issue tracking systems that are managed by, or on behalf of, the Licensor for
+the purpose of discussing and improving the Work, but excluding communication
+that is conspicuously marked or otherwise designated in writing by the copyright
+owner as “Not a Contribution.”
+
+“Contributor” shall mean Licensor and any individual or Legal Entity on behalf
+of whom a Contribution has been received by Licensor and subsequently
+incorporated within the Work.
+
+#### 2. Grant of Copyright License
+
+Subject to the terms and conditions of this License, each Contributor hereby
+grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free,
+irrevocable copyright license to reproduce, prepare Derivative Works of,
+publicly display, publicly perform, sublicense, and distribute the Work and such
+Derivative Works in Source or Object form.
+
+#### 3. Grant of Patent License
+
+Subject to the terms and conditions of this License, each Contributor hereby
+grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free,
+irrevocable (except as stated in this section) patent license to make, have
+made, use, offer to sell, sell, import, and otherwise transfer the Work, where
+such license applies only to those patent claims licensable by such Contributor
+that are necessarily infringed by their Contribution(s) alone or by combination
+of their Contribution(s) with the Work to which such Contribution(s) was
+submitted. If You institute patent litigation against any entity (including a
+cross-claim or counterclaim in a lawsuit) alleging that the Work or a
+Contribution incorporated within the Work constitutes direct or contributory
+patent infringement, then any patent licenses granted to You under this License
+for that Work shall terminate as of the date such litigation is filed.
+
+#### 4. Redistribution
+
+You may reproduce and distribute copies of the Work or Derivative Works thereof
+in any medium, with or without modifications, and in Source or Object form,
+provided that You meet the following conditions:
+
+* **(a)** You must give any other recipients of the Work or Derivative Works a copy of
+this License; and
+* **(b)** You must cause any modified files to carry prominent notices stating that You
+changed the files; and
+* **(c)** You must retain, in the Source form of any Derivative Works that You distribute,
+all copyright, patent, trademark, and attribution notices from the Source form
+of the Work, excluding those notices that do not pertain to any part of the
+Derivative Works; and
+* **(d)** If the Work includes a “NOTICE” text file as part of its distribution, then any
+Derivative Works that You distribute must include a readable copy of the
+attribution notices contained within such NOTICE file, excluding those notices
+that do not pertain to any part of the Derivative Works, in at least one of the
+following places: within a NOTICE text file distributed as part of the
+Derivative Works; within the Source form or documentation, if provided along
+with the Derivative Works; or, within a display generated by the Derivative
+Works, if and wherever such third-party notices normally appear. The contents of
+the NOTICE file are for informational purposes only and do not modify the
+License. You may add Your own attribution notices within Derivative Works that
+You distribute, alongside or as an addendum to the NOTICE text from the Work,
+provided that such additional attribution notices cannot be construed as
+modifying the License.
+
+You may add Your own copyright statement to Your modifications and may provide
+additional or different license terms and conditions for use, reproduction, or
+distribution of Your modifications, or for any such Derivative Works as a whole,
+provided Your use, reproduction, and distribution of the Work otherwise complies
+with the conditions stated in this License.
+
+#### 5. Submission of Contributions
+
+Unless You explicitly state otherwise, any Contribution intentionally submitted
+for inclusion in the Work by You to the Licensor shall be under the terms and
+conditions of this License, without any additional terms or conditions.
+Notwithstanding the above, nothing herein shall supersede or modify the terms of
+any separate license agreement you may have executed with Licensor regarding
+such Contributions.
+
+#### 6. Trademarks
+
+This License does not grant permission to use the trade names, trademarks,
+service marks, or product names of the Licensor, except as required for
+reasonable and customary use in describing the origin of the Work and
+reproducing the content of the NOTICE file.
+
+#### 7. Disclaimer of Warranty
+
+Unless required by applicable law or agreed to in writing, Licensor provides the
+Work (and each Contributor provides its Contributions) on an “AS IS” BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied,
+including, without limitation, any warranties or conditions of TITLE,
+NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A PARTICULAR PURPOSE. You are
+solely responsible for determining the appropriateness of using or
+redistributing the Work and assume any risks associated with Your exercise of
+permissions under this License.
+
+#### 8. Limitation of Liability
+
+In no event and under no legal theory, whether in tort (including negligence),
+contract, or otherwise, unless required by applicable law (such as deliberate
+and grossly negligent acts) or agreed to in writing, shall any Contributor be
+liable to You for damages, including any direct, indirect, special, incidental,
+or consequential damages of any character arising as a result of this License or
+out of the use or inability to use the Work (including but not limited to
+damages for loss of goodwill, work stoppage, computer failure or malfunction, or
+any and all other commercial damages or losses), even if such Contributor has
+been advised of the possibility of such damages.
+
+#### 9. Accepting Warranty or Additional Liability
+
+While redistributing the Work or Derivative Works thereof, You may choose to
+offer, and charge a fee for, acceptance of support, warranty, indemnity, or
+other liability obligations and/or rights consistent with this License. However,
+in accepting such obligations, You may act only on Your own behalf and on Your
+sole responsibility, not on behalf of any other Contributor, and only if You
+agree to indemnify, defend, and hold each Contributor harmless for any liability
+incurred by, or claims asserted against, such Contributor by reason of your
+accepting any such warranty or additional liability.
+
+_END OF TERMS AND CONDITIONS_
+
+### APPENDIX: How to apply the Apache License to your work
+
+To apply the Apache License to your work, attach the following boilerplate
+notice, with the fields enclosed by brackets `[]` replaced with your own
+identifying information. (Don't include the brackets!) The text should be
+enclosed in the appropriate comment syntax for the file format. We also
+recommend that a file or class name and description of purpose be included on
+the same “printed page” as the copyright notice for easier identification within
+third-party archives.
+
+    Copyright [yyyy] [name of copyright owner]
+    
+    Licensed under the Apache License, Version 2.0 (the "License");
+    you may not use this file except in compliance with the License.
+    You may obtain a copy of the License at
+    
+      http://www.apache.org/licenses/LICENSE-2.0
+    
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+    See the License for the specific language governing permissions and
+    limitations under the License.
+

Modules/hal-device/README.md

@@ -0,0 +1,8 @@
+**WARNING: This module contains deprecated code**
+
+This module is the basis for the old Tactility HAL.
+This HAL existed before TactilityKernel.
+
+The C++ `tt::hal::Device` class is replaced by `struct Device` from TactilityKernel.
+
+License: Apache v2.0

Modules/hal-device/Source/drivers/hal_device.cpp

@@ -0,0 +1,126 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <tactility/drivers/hal_device.h>
+#include <tactility/device.h>
+#include <tactility/driver.h>
+
+#include <tactility/log.h>
+#include <tactility/hal/Device.h>
+#include <memory>
+#include <utility>
+
+#define TAG LOG_TAG(HalDevice)
+
+struct HalDevicePrivate {
+    std::shared_ptr<tt::hal::Device> halDevice;
+};
+
+#define GET_DATA(device) ((struct HalDevicePrivate*)device->internal.driver_data)
+
+static enum HalDeviceType getHalDeviceType(tt::hal::Device::Type type) {
+    switch (type) {
+        case tt::hal::Device::Type::I2c:
+            return HalDeviceType::HAL_DEVICE_TYPE_I2C;
+        case tt::hal::Device::Type::Display:
+            return HalDeviceType::HAL_DEVICE_TYPE_DISPLAY;
+        case tt::hal::Device::Type::Touch:
+            return HalDeviceType::HAL_DEVICE_TYPE_TOUCH;
+        case tt::hal::Device::Type::SdCard:
+            return HalDeviceType::HAL_DEVICE_TYPE_SDCARD;
+        case tt::hal::Device::Type::Keyboard:
+            return HalDeviceType::HAL_DEVICE_TYPE_KEYBOARD;
+        case tt::hal::Device::Type::Encoder:
+            return HalDeviceType::HAL_DEVICE_TYPE_ENCODER;
+        case tt::hal::Device::Type::Power:
+            return HalDeviceType::HAL_DEVICE_TYPE_POWER;
+        case tt::hal::Device::Type::Gps:
+            return HalDeviceType::HAL_DEVICE_TYPE_GPS;
+        case tt::hal::Device::Type::Other:
+            return HalDeviceType::HAL_DEVICE_TYPE_OTHER;
+        default:
+            LOG_W(TAG, "Device type %d is not implemented", static_cast<int>(type));
+            return HalDeviceType::HAL_DEVICE_TYPE_OTHER;
+    }
+}
+
+extern "C" {
+
+HalDeviceType hal_device_get_type(struct Device* device) {
+    auto type = GET_DATA(device)->halDevice->getType();
+    return getHalDeviceType(type);
+}
+
+void hal_device_for_each_of_type(HalDeviceType type, void* context, bool(*onDevice)(struct Device* device, void* context)) {
+    struct InternalContext {
+        HalDeviceType typeParam;
+        void* contextParam;
+        bool(*onDeviceParam)(struct Device* device, void* context);
+    };
+
+    InternalContext internal_context = {
+        .typeParam = type,
+        .contextParam = context,
+        .onDeviceParam = onDevice
+    };
+
+    for_each_device_of_type(&HAL_DEVICE_TYPE, &internal_context, [](Device* device, void* context){
+        auto* hal_device_private = GET_DATA(device);
+        auto* internal_context = static_cast<InternalContext*>(context);
+        auto hal_device_type = getHalDeviceType(hal_device_private->halDevice->getType());
+        if (hal_device_type == internal_context->typeParam) {
+            if (!internal_context->onDeviceParam(device, internal_context->contextParam)) {
+                return false;
+            }
+        }
+        return true;
+    });
+}
+
+}
+
+namespace tt::hal {
+
+std::shared_ptr<Device> hal_device_get_device(::Device* device) {
+    auto* hal_device_private = GET_DATA(device);
+    return hal_device_private->halDevice;
+}
+
+void hal_device_set_device(::Device* kernelDevice, std::shared_ptr<Device> halDevice) {
+    GET_DATA(kernelDevice)->halDevice = std::move(halDevice);
+}
+
+}
+
+#pragma region Lifecycle
+
+static error_t start(Device* device) {
+    LOG_I(TAG, "start %s", device->name);
+    device->internal.driver_data = new HalDevicePrivate();
+    return ERROR_NONE;
+}
+
+static error_t stop(Device* device) {
+    LOG_I(TAG, "stop %s", device->name);
+    delete GET_DATA(device);
+    return ERROR_NONE;
+}
+
+#pragma endregion
+
+extern "C" {
+
+const struct DeviceType HAL_DEVICE_TYPE {0};
+
+extern struct Module hal_device_module;
+
+Driver hal_device_driver = {
+    .name = "hal-device",
+    .compatible = (const char*[]) {"hal-device", nullptr},
+    .startDevice = start,
+    .stopDevice = stop,
+    .api = nullptr,
+    .deviceType = &HAL_DEVICE_TYPE,
+    .owner = &hal_device_module,
+    .driver_private = nullptr
+};
+
+}

Modules/hal-device/Source/hal/Device.cpp

@@ -0,0 +1,143 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <tactility/hal/Device.h>
+#include <tactility/driver.h>
+#include <tactility/drivers/hal_device.hpp>
+
+#include <Tactility/Logger.h>
+#include <Tactility/RecursiveMutex.h>
+#include <algorithm>
+
+namespace tt::hal {
+
+RecursiveMutex mutex;
+static Device::Id nextId = 0;
+
+static const auto LOGGER = Logger("Devices");
+
+Device::Device() : id(nextId++) {}
+
+static std::shared_ptr<Device::KernelDeviceHolder> createKernelDeviceHolder(const std::shared_ptr<Device>& device) {
+    auto kernel_device_name = std::format("hal-device-{}", device->getId());
+    LOGGER.info("Registering {} with id {} as kernel device {}", device->getName(), device->getId(), kernel_device_name);
+    auto kernel_device_holder = std::make_shared<Device::KernelDeviceHolder>(kernel_device_name);
+    auto* kernel_device = kernel_device_holder->device.get();
+    check(device_construct(kernel_device) == ERROR_NONE);
+    check(device_add(kernel_device) == ERROR_NONE);
+    auto* driver = driver_find_compatible("hal-device");
+    check(driver);
+    device_set_driver(kernel_device, driver);
+    check(device_start(kernel_device) == ERROR_NONE);
+    hal_device_set_device(kernel_device, device);
+    return kernel_device_holder;
+}
+
+static void destroyKernelDeviceHolder(std::shared_ptr<Device::KernelDeviceHolder>& holder) {
+    auto kernel_device = holder->device.get();
+    hal_device_set_device(kernel_device, nullptr);
+    check(device_stop(kernel_device) == ERROR_NONE);
+    check(device_remove(kernel_device) == ERROR_NONE);
+    check(device_destruct(kernel_device) == ERROR_NONE);
+    holder->device = nullptr;
+}
+
+void registerDevice(const std::shared_ptr<Device>& device) {
+    auto scoped_mutex = mutex.asScopedLock();
+    scoped_mutex.lock();
+
+    if (device->getKernelDeviceHolder() == nullptr) {
+        // Kernel device
+        auto kernel_device_holder = createKernelDeviceHolder(device);
+        device->setKernelDeviceHolder(kernel_device_holder);
+    } else {
+        LOGGER.warn("Device {} with id {} was already registered", device->getName(), device->getId());
+    }
+}
+
+void deregisterDevice(const std::shared_ptr<Device>& device) {
+    auto scoped_mutex = mutex.asScopedLock();
+    scoped_mutex.lock();
+
+    // Kernel device
+    auto kernel_device_holder = device->getKernelDeviceHolder();
+    if (kernel_device_holder) {
+        destroyKernelDeviceHolder(kernel_device_holder);
+        device->setKernelDeviceHolder(nullptr);
+    } else {
+        LOGGER.warn("Device {} with id {} was not registered", device->getName(), device->getId());
+    }
+}
+
+template<typename R>
+auto toVector(R&& range) {
+    using T = std::ranges::range_value_t<R>;
+    std::vector<T> result;
+    if constexpr (std::ranges::common_range<R>) {
+        result.reserve(std::ranges::distance(range));
+    }
+    std::ranges::copy(range, std::back_inserter(result));
+    return result;
+}
+
+std::vector<std::shared_ptr<Device>> findDevices(const std::function<bool(const std::shared_ptr<Device>&)>& filterFunction) {
+    auto scoped_mutex = mutex.asScopedLock();
+    scoped_mutex.lock();
+
+    auto devices_view = getDevices() | std::views::filter([&filterFunction](auto& device) {
+        return filterFunction(device);
+    });
+    return toVector(devices_view);
+}
+
+std::shared_ptr<Device> _Nullable findDevice(const std::function<bool(const std::shared_ptr<Device>&)>& filterFunction) {
+    auto scoped_mutex = mutex.asScopedLock();
+    scoped_mutex.lock();
+
+    auto result_set = getDevices() | std::views::filter([&filterFunction](auto& device) {
+         return filterFunction(device);
+    });
+    if (!result_set.empty()) {
+        return result_set.front();
+    } else {
+        return nullptr;
+    }
+}
+
+std::shared_ptr<Device> _Nullable findDevice(std::string name) {
+    return findDevice([&name](auto& device){
+        return device->getName() == name;
+    });
+}
+
+std::shared_ptr<Device> _Nullable findDevice(Device::Id id) {
+    return findDevice([id](auto& device){
+      return device->getId() == id;
+    });
+}
+
+std::vector<std::shared_ptr<Device>> findDevices(Device::Type type) {
+    return findDevices([type](auto& device) {
+        return device->getType() == type;
+    });
+}
+
+std::vector<std::shared_ptr<Device>> getDevices() {
+    std::vector<std::shared_ptr<Device>> devices;
+    for_each_device_of_type(&HAL_DEVICE_TYPE, &devices ,[](auto* kernelDevice, auto* context) {
+        auto devices_ptr = static_cast<std::vector<std::shared_ptr<Device>>*>(context);
+        auto hal_device = hal_device_get_device(kernelDevice);
+        (*devices_ptr).push_back(hal_device);
+        return true;
+    });
+    return devices;
+}
+
+bool hasDevice(Device::Type type) {
+    auto scoped_mutex = mutex.asScopedLock();
+    scoped_mutex.lock();
+    auto result_set = getDevices() | std::views::filter([&type](auto& device) {
+         return device->getType() == type;
+    });
+    return !result_set.empty();
+}
+
+}

Modules/hal-device/Source/module.cpp

@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <tactility/check.h>
+#include <tactility/driver.h>
+#include <tactility/module.h>
+
+extern "C" {
+
+extern Driver hal_device_driver;
+
+static error_t start() {
+    /* We crash when construct fails, because if a single driver fails to construct,
+     * there is no guarantee that the previously constructed drivers can be destroyed */
+    check(driver_construct_add(&hal_device_driver) == ERROR_NONE);
+    return ERROR_NONE;
+}
+
+static error_t stop() {
+    /* We crash when destruct fails, because if a single driver fails to destruct,
+     * there is no guarantee that the previously destroyed drivers can be recovered */
+    check(driver_remove(&hal_device_driver) == ERROR_NONE);
+    check(driver_destruct(&hal_device_driver) == ERROR_NONE);
+    return ERROR_NONE;
+}
+
+struct Module hal_device_module = {
+    .name = "hal-device",
+    .start = start,
+    .stop = stop
+};
+
+}

Platforms/PlatformEsp32/Source/drivers/esp32_gpio.cpp

@@ -11,7 +11,7 @@
 
 #define TAG LOG_TAG(esp32_gpio)
 
-#define GET_CONFIG(device) ((struct Esp32GpioConfig*)device->internal.driver_data)
+#define GET_CONFIG(device) ((struct Esp32GpioConfig*)device->config)
 
 extern "C" {
 

Platforms/PlatformEsp32/Source/module.cpp

@@ -10,22 +10,22 @@ extern Driver esp32_i2c_driver;
 static error_t start() {
     /* We crash when construct fails, because if a single driver fails to construct,
      * there is no guarantee that the previously constructed drivers can be destroyed */
-    check(driver_construct(&esp32_gpio_driver) == ERROR_NONE);
+    check(driver_construct_add(&esp32_gpio_driver) == ERROR_NONE);
-    check(driver_construct(&esp32_i2c_driver) == ERROR_NONE);
+    check(driver_construct_add(&esp32_i2c_driver) == ERROR_NONE);
     return ERROR_NONE;
 }
 
 static error_t stop() {
     /* We crash when destruct fails, because if a single driver fails to destruct,
      * there is no guarantee that the previously destroyed drivers can be recovered */
-    check(driver_destruct(&esp32_gpio_driver) == ERROR_NONE);
+    check(driver_remove_destruct(&esp32_gpio_driver) == ERROR_NONE);
-    check(driver_destruct(&esp32_i2c_driver) == ERROR_NONE);
+    check(driver_remove_destruct(&esp32_i2c_driver) == ERROR_NONE);
     return ERROR_NONE;
 }
 
 // The name must be exactly "platform_module"
 struct Module platform_module = {
-    .name = "ESP32 Platform",
+    .name = "platform-esp32",
     .start = start,
     .stop = stop
 };

Platforms/PlatformPosix/Source/module.cpp

@@ -14,7 +14,7 @@ static error_t stop() {
 
 // The name must be exactly "platform_module"
 struct Module platform_module = {
-    .name = "POSIX Platform",
+    .name = "platform-posix",
     .start = start,
     .stop = stop
 };

Tactility/CMakeLists.txt

@@ -8,6 +8,7 @@ if (DEFINED ENV{ESP_IDF_VERSION})
         PlatformEsp32
         TactilityCore
         TactilityFreeRtos
+        hal-device
         lvgl
         driver
         elf_loader
@@ -71,6 +72,7 @@ else()
         TactilityCore
         TactilityKernel
         PlatformPosix
+        hal-device
         freertos_kernel
         lvgl
         lv_screenshot

Tactility/Include/Tactility/hal/display/DisplayDevice.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include "../Device.h"
+#include <tactility/hal/Device.h>
 
 #include <lvgl.h>
 

Tactility/Include/Tactility/hal/encoder/EncoderDevice.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include "../Device.h"
+#include <tactility/hal/Device.h>
 
 #include <lvgl.h>
 

Tactility/Include/Tactility/hal/gps/GpsDevice.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include "../Device.h"
+#include <tactility/hal/Device.h>
 #include "GpsConfiguration.h"
 #include "Satellites.h"
 
@@ -110,7 +110,7 @@ public:
         return lastRmcSubscriptionId;
     }
 
-    void unsubscribeRmc(GgaSubscriptionId subscriptionId) {
+    void unsubscribeRmc(RmcSubscriptionId subscriptionId) {
         auto lock = mutex.asScopedLock();
         lock.lock();
         std::erase_if(rmcSubscriptions, [subscriptionId](auto& subscription) { return subscription.id == subscriptionId; });

Tactility/Include/Tactility/hal/i2c/I2cDevice.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include "../Device.h"
+#include <tactility/hal/Device.h>
 #include "I2c.h"
 
 namespace tt::hal::i2c {

Tactility/Include/Tactility/hal/keyboard/KeyboardDevice.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include "../Device.h"
+#include <tactility/hal/Device.h>
 
 #include <lvgl.h>
 

Tactility/Include/Tactility/hal/power/PowerDevice.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include "../Device.h"
+#include <tactility/hal/Device.h>
 #include <cstdint>
 
 namespace tt::hal::power {
@@ -44,4 +44,4 @@ public:
     virtual void powerOff() { /* NO-OP*/ }
 };
 
-} // namespace tt
+}

Tactility/Include/Tactility/hal/sdcard/SdCardDevice.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include "../Device.h"
+#include <tactility/hal/Device.h>
 
 #include <Tactility/TactilityCore.h>
 #include <Tactility/Lock.h>

Tactility/Include/Tactility/hal/sdcard/SdmmcDevice.h

@@ -5,7 +5,7 @@
 #include "SdCardDevice.h"
 
 #include <Tactility/RecursiveMutex.h>
-#include <Tactility/hal/Device.h>
+#include <tactility/hal/Device.h>
 #include <Tactility/hal/spi/Spi.h>
 #include <sd_protocol_types.h>
 #include <soc/gpio_num.h>

Tactility/Include/Tactility/hal/touch/TouchDevice.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include "../Device.h"
+#include <tactility/hal/Device.h>
 #include "TouchDriver.h"
 
 #include <lvgl.h>

Tactility/Source/MountPoints.cpp

@@ -1,7 +1,7 @@
 #include "Tactility/MountPoints.h"
 
 #include "Tactility/TactilityConfig.h"
-#include "Tactility/hal/Device.h"
+#include <tactility/hal/Device.h>
 #include "Tactility/hal/sdcard/SdCardDevice.h"
 
 #include <Tactility/file/File.h>

Tactility/Source/Tactility.cpp

@@ -23,6 +23,7 @@
 #include <Tactility/settings/TimePrivate.h>
 
 #include <tactility/kernel_init.h>
+#include <tactility/hal_device_module.h>
 
 #include <map>
 #include <format>
@@ -38,6 +39,11 @@ static auto LOGGER = Logger("Tactility");
 static const Configuration* config_instance = nullptr;
 static Dispatcher mainDispatcher;
 
+struct ModuleParent tactility_module_parent  {
+    "tactility",
+    nullptr
+};
+
 // region Default services
 namespace service {
     // Primary
@@ -330,6 +336,11 @@ void run(const Configuration& config, Module* platformModule, Module* deviceModu
         return;
     }
 
+    // HAL compatibility module: it creates kernel driver wrappers for tt::hal::Device
+    check(module_parent_construct(&tactility_module_parent) == ERROR_NONE);
+    check(module_set_parent(&hal_device_module, &tactility_module_parent) == ERROR_NONE);
+    check(module_start(&hal_device_module) == ERROR_NONE);
+
     const hal::Configuration& hardware = *config.hardware;
 
     // Assign early so starting services can use it

Tactility/Source/app/AppInstall.cpp

@@ -5,7 +5,7 @@
 #include <Tactility/file/File.h>
 #include <Tactility/file/FileLock.h>
 #include <Tactility/file/PropertiesFile.h>
-#include <Tactility/hal/Device.h>
+#include <tactility/hal/Device.h>
 #include <Tactility/Logger.h>
 #include <Tactility/Paths.h>
 

Tactility/Source/app/crashdiagnostics/CrashDiagnostics.cpp

@@ -3,7 +3,7 @@
 #include <Tactility/app/crashdiagnostics/QrHelpers.h>
 #include <Tactility/app/crashdiagnostics/QrUrl.h>
 #include <Tactility/app/launcher/Launcher.h>
-#include <Tactility/hal/Device.h>
+#include <tactility/hal/Device.h>
 #include <Tactility/Logger.h>
 #include <Tactility/lvgl/Statusbar.h>
 #include <Tactility/service/loader/Loader.h>

Tactility/Source/app/power/Power.cpp

@@ -7,7 +7,7 @@
 #include <Tactility/hal/power/PowerDevice.h>
 #include <Tactility/Timer.h>
 #include <Tactility/Assets.h>
-#include <Tactility/hal/Device.h>
+#include <tactility/hal/Device.h>
 
 #include <lvgl.h>
 

Tactility/Source/app/systeminfo/SystemInfo.cpp

@@ -3,7 +3,7 @@
 #include <Tactility/lvgl/LvglSync.h>
 
 #include <Tactility/Assets.h>
-#include <Tactility/hal/Device.h>
+#include <tactility/hal/Device.h>
 #include <Tactility/Tactility.h>
 #include <Tactility/Timer.h>
 

Tactility/Source/file/ObjectFileWriter.cpp

@@ -16,7 +16,7 @@ bool ObjectFileWriter::open() {
     }
 
     // Edit existing or create a new file
-    auto opening_file = std::unique_ptr<FILE, FileCloser>(std::fopen(filePath.c_str(), "wb"));
+    auto opening_file = std::unique_ptr<FILE, FileCloser>(std::fopen(filePath.c_str(), edit_existing ? "rb+" : "wb"));
     if (opening_file == nullptr) {
         LOGGER.error("Failed to open file {}", filePath);
         return false;

Tactility/Source/hal/Device.cpp

@@ -1,106 +0,0 @@
-#include <Tactility/hal/Device.h>
-
-#include <Tactility/Logger.h>
-#include <Tactility/RecursiveMutex.h>
-#include <algorithm>
-
-namespace tt::hal {
-
-std::vector<std::shared_ptr<Device>> devices;
-RecursiveMutex mutex;
-static Device::Id nextId = 0;
-
-static const auto LOGGER = Logger("Devices");
-
-Device::Device() : id(nextId++) {}
-
-template <std::ranges::range RangeType>
-auto toVector(RangeType&& range) {
-    auto view = range | std::views::common;
-    return std::vector(view.begin(), view.end());
-}
-
-void registerDevice(const std::shared_ptr<Device>& device) {
-    auto scoped_mutex = mutex.asScopedLock();
-    scoped_mutex.lock();
-
-    if (findDevice(device->getId()) == nullptr) {
-        devices.push_back(device);
-        LOGGER.info("Registered {} with id {}", device->getName(), device->getId());
-    } else {
-        LOGGER.warn("Device {} with id {} was already registered", device->getName(), device->getId());
-    }
-}
-
-void deregisterDevice(const std::shared_ptr<Device>& device) {
-    auto scoped_mutex = mutex.asScopedLock();
-    scoped_mutex.lock();
-
-    auto id_to_remove = device->getId();
-    auto remove_iterator = std::remove_if(devices.begin(), devices.end(), [id_to_remove](const auto& device) {
-        return device->getId() == id_to_remove;
-    });
-    if (remove_iterator != devices.end()) {
-        LOGGER.info("Deregistering {} with id {}", device->getName(), device->getId());
-        devices.erase(remove_iterator);
-    } else {
-        LOGGER.warn("Deregistering {} with id {} failed: not found", device->getName(), device->getId());
-    }
-}
-
-std::vector<std::shared_ptr<Device>> findDevices(const std::function<bool(const std::shared_ptr<Device>&)>& filterFunction) {
-    auto scoped_mutex = mutex.asScopedLock();
-    scoped_mutex.lock();
-
-    auto devices_view = devices | std::views::filter([&filterFunction](auto& device) {
-        return filterFunction(device);
-    });
-    return toVector(devices_view);
-}
-
-std::shared_ptr<Device> _Nullable findDevice(const std::function<bool(const std::shared_ptr<Device>&)>& filterFunction) {
-    auto scoped_mutex = mutex.asScopedLock();
-    scoped_mutex.lock();
-
-    auto result_set = devices | std::views::filter([&filterFunction](auto& device) {
-         return filterFunction(device);
-    });
-    if (!result_set.empty()) {
-        return result_set.front();
-    } else {
-        return nullptr;
-    }
-}
-
-std::shared_ptr<Device> _Nullable findDevice(std::string name) {
-    return findDevice([&name](auto& device){
-        return device->getName() == name;
-    });
-}
-
-std::shared_ptr<Device> _Nullable findDevice(Device::Id id) {
-    return findDevice([id](auto& device){
-      return device->getId() == id;
-    });
-}
-
-std::vector<std::shared_ptr<Device>> findDevices(Device::Type type) {
-    return findDevices([type](auto& device) {
-        return device->getType() == type;
-    });
-}
-
-std::vector<std::shared_ptr<Device>> getDevices() {
-    return devices;
-}
-
-bool hasDevice(Device::Type type) {
-    auto scoped_mutex = mutex.asScopedLock();
-    scoped_mutex.lock();
-    auto result_set = devices | std::views::filter([&type](auto& device) {
-         return device->getType() == type;
-    });
-    return !result_set.empty();
-}
-
-}

Tactility/Source/hal/Hal.cpp

@@ -2,7 +2,7 @@
 #include <Tactility/Tactility.h>
 #include <tactility/check.h>
 #include <Tactility/hal/Configuration.h>
-#include <Tactility/hal/Device.h>
+#include <tactility/hal/Device.h>
 #include <Tactility/hal/power/PowerDevice.h>
 #include <Tactility/hal/spi/SpiInit.h>
 #include <Tactility/hal/uart/UartInit.h>

Tactility/Source/hal/sdcard/SdCard.cpp

@@ -1,4 +1,4 @@
-#include "Tactility/hal/Device.h"
+#include <tactility/hal/Device.h>
 #include "Tactility/hal/sdcard/SdCardDevice.h"
 
 namespace tt::hal::sdcard {

Tactility/Source/service/webserver/WebServerService.cpp

@@ -14,7 +14,7 @@
 
 #include <Tactility/Tactility.h>
 #include <Tactility/TactilityConfig.h>
-#include <Tactility/hal/Device.h>
+#include <tactility/hal/Device.h>
 #include <Tactility/app/AppRegistration.h>
 #include <Tactility/app/AppManifest.h>
 #include <Tactility/app/App.h>

Tactility/Source/settings/DisplaySettings.cpp

@@ -1,7 +1,7 @@
 #include <Tactility/settings/DisplaySettings.h>
 
 #include <Tactility/file/PropertiesFile.h>
-#include <Tactility/hal/Device.h>
+#include <tactility/hal/Device.h>
 #include <Tactility/hal/display/DisplayDevice.h>
 
 #include <map>

TactilityC/Include/tt_hal_device.h

@@ -15,7 +15,7 @@ typedef enum {
     DEVICE_TYPE_KEYBOARD,
     DEVICE_TYPE_POWER,
     DEVICE_TYPE_GPS
-} DeviceType;
+} TtDeviceType;
 
 typedef uint32_t DeviceId;
 
@@ -27,7 +27,7 @@ typedef uint32_t DeviceId;
  * @param[in] maxCount the maximum number of items that the "deviceIds" output can contain (minimum value is 1)
  * @return true if one or more devices were found
  */
-bool tt_hal_device_find(DeviceType type, DeviceId* deviceIds, uint16_t* count, uint16_t maxCount);
+bool tt_hal_device_find(TtDeviceType type, DeviceId* deviceIds, uint16_t* count, uint16_t maxCount);
 
 #ifdef __cplusplus
 }

TactilityC/Source/tt_hal_device.cpp

@@ -2,9 +2,9 @@
 
 #include <tactility/check.h>
 
-#include <Tactility/hal/Device.h>
+#include <tactility/hal/Device.h>
 
-static tt::hal::Device::Type toTactilityDeviceType(DeviceType type) {
+static tt::hal::Device::Type toTactilityDeviceType(TtDeviceType type) {
     switch (type) {
         case DEVICE_TYPE_I2C:
             return tt::hal::Device::Type::I2c;
@@ -27,7 +27,7 @@ static tt::hal::Device::Type toTactilityDeviceType(DeviceType type) {
 
 extern "C" {
 
-bool tt_hal_device_find(DeviceType type, DeviceId* deviceIds, uint16_t* count, uint16_t maxCount) {
+bool tt_hal_device_find(TtDeviceType type, DeviceId* deviceIds, uint16_t* count, uint16_t maxCount) {
     assert(maxCount > 0);
 
     int16_t currentIndex = -1;

TactilityC/Source/tt_hal_display.cpp

@@ -2,7 +2,7 @@
 
 #include <tactility/check.h>
 
-#include <Tactility/hal/Device.h>
+#include <tactility/hal/Device.h>
 #include <Tactility/hal/display/DisplayDevice.h>
 #include <Tactility/hal/display/DisplayDriver.h>
 

TactilityC/Source/tt_hal_gpio.cpp

@@ -24,7 +24,7 @@ bool tt_hal_gpio_get_level(GpioPin pin) {
     Device* device_result = find_first_gpio_controller();
     if (device_result == nullptr) return false;
     bool pin_state = false;
-    if (!gpio_controller_get_level(device_result, pin, &pin_state)) return false;
+    if (gpio_controller_get_level(device_result, pin, &pin_state) != ERROR_NONE) return false;
     return pin_state;
 }
 
@@ -32,7 +32,7 @@ int tt_hal_gpio_get_pin_count() {
     Device* device_result = find_first_gpio_controller();
     if (device_result == nullptr) return 0;
     uint32_t pin_count = 0;
-    if (!gpio_controller_get_pin_count(device_result, &pin_count)) return 0;
+    if (gpio_controller_get_pin_count(device_result, &pin_count) != ERROR_NONE) return 0;
     return (int)pin_count;
 }
 

TactilityC/Source/tt_hal_touch.cpp

@@ -1,6 +1,6 @@
 #include "tt_hal_touch.h"
 
-#include "Tactility/hal/Device.h"
+#include <tactility/hal/Device.h>
 #include "Tactility/hal/touch/TouchDevice.h"
 #include "Tactility/hal/touch/TouchDriver.h"
 

TactilityFreeRtos/Include/Tactility/freertoscompat/PortCompat.h

@@ -4,5 +4,10 @@
 #include "RTOS.h"
 
 #ifndef ESP_PLATFORM
-#define xPortInIsrContext(x) (false)
+
+// TactilityKernel co-existence check
+#ifndef xPortInIsrContext
+#define xPortInIsrContext() (false)
+#endif
+
 #endif

TactilityKernel/Include/tactility/driver.h

@@ -37,6 +37,14 @@ error_t driver_construct(struct Driver* driver);
 
 error_t driver_destruct(struct Driver* driver);
 
+error_t driver_add(struct Driver* driver);
+
+error_t driver_remove(struct Driver* driver);
+
+error_t driver_construct_add(struct Driver* driver);
+
+error_t driver_remove_destruct(struct Driver* driver);
+
 error_t driver_bind(struct Driver* driver, struct Device* device);
 
 error_t driver_unbind(struct Driver* driver, struct Device* device);

TactilityKernel/Include/tactility/freertos/port.h

@@ -5,6 +5,15 @@
 #include "freertos.h"
 
 #ifndef ESP_PLATFORM
+
+// TactilityFreeRTOS co-existence check
+#ifndef xPortInIsrContext
 #define xPortInIsrContext() (pdFALSE)
+#endif
+
+// TactilityFreeRTOS co-existence check
+#ifndef vPortAssertIfInISR
 #define vPortAssertIfInISR()
 #endif
+
+#endif

TactilityKernel/Include/tactility/kernel_init.h

@@ -11,8 +11,8 @@ extern "C" {
 /**
  * Initialize the kernel with platform and device modules, and a device tree.
  * @param platform_module The platform module to start. This module should not be constructed yet.
- * @param device_module The device module to start. This module should not be constructed yet.
+ * @param device_module The device module to start. This module should not be constructed yet. This parameter can be NULL.
- * @param devicetree_devices The list of generated devices from the devicetree. The array must be terminated by an entry { NULL, NULL }
+ * @param devicetree_devices The list of generated devices from the devicetree. The array must be terminated by an entry { NULL, NULL }. This parameter can be NULL.
  * @return ERROR_NONE on success, otherwise an error code
  */
 error_t kernel_init(struct Module* platform_module, struct Module* device_module, struct CompatibleDevice devicetree_devices[]);

TactilityKernel/Include/tactility/module.h

@@ -17,6 +17,8 @@ struct Module {
     /**
      * The name of the module, for logging/debugging purposes
      * Should never be NULL.
+     * Characters allowed: a-z A-Z 0-9 - _ .
+     * Desirable format "platform-esp32", "lilygo-tdeck", etc.
      */
     const char* name;
 

TactilityKernel/Source/crash.cpp

@@ -1,3 +1,4 @@
+#include <cstdlib>
 #include <tactility/freertos/task.h>
 #include <tactility/log.h>
 
@@ -31,7 +32,7 @@ __attribute__((noreturn)) void __crash(void) {
 #ifdef ESP_PLATFORM
     esp_system_abort("System halted. Connect debugger for more info.");
 #else
-    while (true) { /* Indefinite lock-up */ }
+    exit(1);
 #endif
     __builtin_unreachable();
 }

TactilityKernel/Source/device.cpp

@@ -49,7 +49,7 @@ error_t device_construct(Device* device) {
     if (device->internal.device_private == nullptr) {
         return ERROR_OUT_OF_MEMORY;
     }
-    LOG_I(TAG, "construct %s", device->name);
+    LOG_D(TAG, "construct %s", device->name);
     mutex_construct(&device->internal.mutex);
     return ERROR_NONE;
 }
@@ -61,7 +61,7 @@ error_t device_destruct(Device* device) {
     if (!get_device_private(device)->children.empty()) {
         return ERROR_INVALID_STATE;
     }
-    LOG_I(TAG, "destruct %s", device->name);
+    LOG_D(TAG, "destruct %s", device->name);
     mutex_destruct(&device->internal.mutex);
     delete get_device_private(device);
     device->internal.device_private = nullptr;
@@ -88,7 +88,7 @@ static void device_remove_child(struct Device* device, struct Device* child) {
 }
 
 error_t device_add(Device* device) {
-    LOG_I(TAG, "add %s", device->name);
+    LOG_D(TAG, "add %s", device->name);
 
     // Already added
     if (device->internal.state.started || device->internal.state.added) {
@@ -111,7 +111,7 @@ error_t device_add(Device* device) {
 }
 
 error_t device_remove(Device* device) {
-    LOG_I(TAG, "remove %s", device->name);
+    LOG_D(TAG, "remove %s", device->name);
 
     if (device->internal.state.started || !device->internal.state.added) {
         return ERROR_INVALID_STATE;

TactilityKernel/Source/driver.cpp

@@ -58,28 +58,6 @@ static DriverLedger& get_ledger() {
 #define driver_lock(driver) mutex_lock(&get_driver_private(driver)->mutex);
 #define driver_unlock(driver) mutex_unlock(&get_driver_private(driver)->mutex);
 
-static void driver_add(Driver* driver) {
-    LOG_I(TAG, "add %s", driver->name);
-    ledger.lock();
-    ledger.drivers.push_back(driver);
-    ledger.unlock();
-}
-
-static error_t driver_remove(Driver* driver) {
-    LOG_I(TAG, "remove %s", driver->name);
-
-    ledger.lock();
-    const auto iterator = std::ranges::find(ledger.drivers, driver);
-    if (iterator == ledger.drivers.end()) {
-        ledger.unlock();
-        return ERROR_NOT_FOUND;
-    }
-    ledger.drivers.erase(iterator);
-    ledger.unlock();
-
-    return ERROR_NONE;
-}
-
 extern "C" {
 
 error_t driver_construct(Driver* driver) {
@@ -87,7 +65,6 @@ error_t driver_construct(Driver* driver) {
     if (driver->driver_private == nullptr) {
         return ERROR_OUT_OF_MEMORY;
     }
-    driver_add(driver);
     return ERROR_NONE;
 }
 
@@ -104,10 +81,6 @@ error_t driver_destruct(Driver* driver) {
     }
     get_driver_private(driver)->destroying = true;
 
-    if (driver_remove(driver) != ERROR_NONE) {
-        LOG_W(TAG, "Failed to remove driver from ledger: %s", driver->name);
-    }
-
     driver_unlock(driver);
     delete get_driver_private(driver);
     driver->driver_private = nullptr;
@@ -115,6 +88,41 @@ error_t driver_destruct(Driver* driver) {
     return ERROR_NONE;
 }
 
+error_t driver_add(Driver* driver) {
+    LOG_I(TAG, "add %s", driver->name);
+    ledger.lock();
+    ledger.drivers.push_back(driver);
+    ledger.unlock();
+    return ERROR_NONE;
+}
+
+error_t driver_remove(Driver* driver) {
+    LOG_I(TAG, "remove %s", driver->name);
+
+    ledger.lock();
+    const auto iterator = std::ranges::find(ledger.drivers, driver);
+    if (iterator == ledger.drivers.end()) {
+        ledger.unlock();
+        return ERROR_NOT_FOUND;
+    }
+    ledger.drivers.erase(iterator);
+    ledger.unlock();
+
+    return ERROR_NONE;
+}
+
+error_t driver_construct_add(struct Driver* driver) {
+    if (driver_construct(driver) != ERROR_NONE) return ERROR_RESOURCE;
+    if (driver_add(driver) != ERROR_NONE) return ERROR_RESOURCE;
+    return ERROR_NONE;
+}
+
+error_t driver_remove_destruct(struct Driver* driver) {
+    if (driver_remove(driver) != ERROR_NONE) return ERROR_RESOURCE;
+    if (driver_destruct(driver) != ERROR_NONE) return ERROR_RESOURCE;
+    return ERROR_NONE;
+}
+
 bool driver_is_compatible(Driver* driver, const char* compatible) {
     if (compatible == nullptr || driver->compatible == nullptr) {
         return false;

TactilityKernel/Source/kernel_init.cpp

@@ -14,7 +14,7 @@ struct ModuleParent kernel_module_parent = {
 
 static error_t init_kernel_drivers() {
     extern Driver root_driver;
-    if (driver_construct(&root_driver) != ERROR_NONE) return ERROR_RESOURCE;
+    if (driver_construct_add(&root_driver) != ERROR_NONE) return ERROR_RESOURCE;
     return ERROR_NONE;
 }
 
@@ -37,19 +37,23 @@ error_t kernel_init(struct Module* platform_module, struct Module* device_module
         return ERROR_RESOURCE;
     }
 
-    module_set_parent(device_module, &kernel_module_parent);
+    if (device_module != nullptr) {
-    if (module_start(device_module) != ERROR_NONE) {
+        module_set_parent(device_module, &kernel_module_parent);
-        LOG_E(TAG, "init failed to start device module");
+        if (module_start(device_module) != ERROR_NONE) {
-        return ERROR_RESOURCE;
+            LOG_E(TAG, "init failed to start device module");
-    }
-
-    CompatibleDevice* compatible_device = devicetree_devices;
-    while (compatible_device->device != nullptr) {
-        if (device_construct_add_start(compatible_device->device, compatible_device->compatible) != ERROR_NONE) {
-            LOG_E(TAG, "kernel_init failed to construct device: %s (%s)", compatible_device->device->name, compatible_device->compatible);
             return ERROR_RESOURCE;
         }
-        compatible_device++;
+    }
+
+    if (devicetree_devices) {
+        CompatibleDevice* compatible_device = devicetree_devices;
+        while (compatible_device->device != nullptr) {
+            if (device_construct_add_start(compatible_device->device, compatible_device->compatible) != ERROR_NONE) {
+                LOG_E(TAG, "kernel_init failed to construct device: %s (%s)", compatible_device->device->name, compatible_device->compatible);
+                return ERROR_RESOURCE;
+            }
+            compatible_device++;
+        }
     }
 
     LOG_I(TAG, "init done");

TactilityKernel/Source/module.cpp

@@ -3,6 +3,8 @@
 #include <tactility/concurrent/mutex.h>
 #include <tactility/module.h>
 
+#define TAG LOG_TAG(module)
+
 struct ModuleParentPrivate {
     std::vector<struct Module*> modules;
     struct Mutex mutex = { 0 };
@@ -72,6 +74,8 @@ error_t module_set_parent(struct Module* module, struct ModuleParent* parent) {
 }
 
 error_t module_start(struct Module* module) {
+    LOG_I(TAG, "start %s", module->name);
+
     if (module->internal.started) return ERROR_NONE;
     if (!module->internal.parent) return ERROR_INVALID_STATE;
 
@@ -85,6 +89,8 @@ bool module_is_started(struct Module* module) {
 }
 
 error_t module_stop(struct Module* module) {
+    LOG_I(TAG, "stop %s", module->name);
+
     if (!module->internal.started) return ERROR_NONE;
 
     error_t error = module->stop();

Tests/Tactility/CMakeLists.txt

@@ -22,6 +22,8 @@ target_link_libraries(TactilityTests PRIVATE
     Tactility
     TactilityCore
     TactilityKernel
+    PlatformPosix
+    hal-device
     Simulator
     SDL2::SDL2-static SDL2-static
 )

Tests/Tactility/HalDeviceTest.cpp

@@ -1,5 +1,5 @@
 #include "doctest.h"
-#include <Tactility/hal/Device.h>
+#include <tactility/hal/Device.h>
 
 #include <utility>
 

Tests/Tactility/Main.cpp

@@ -5,12 +5,27 @@
 #include "FreeRTOS.h"
 #include "task.h"
 
+#include <tactility/kernel_init.h>
+#include <tactility/hal_device_module.h>
+
 typedef struct {
     int argc;
     char** argv;
     int result;
 } TestTaskData;
 
+extern "C" {
+// From the relevant platform
+extern struct Module platform_module;
+// From the relevant device
+extern struct Module device_module;
+}
+
+struct ModuleParent tactility_tests_module_parent  {
+    "tactility-tests",
+    nullptr
+};
+
 void test_task(void* parameter) {
     auto* data = (TestTaskData*)parameter;
 
@@ -21,6 +36,12 @@ void test_task(void* parameter) {
     // overrides
     context.setOption("no-breaks", true); // don't break in the debugger when assertions fail
 
+    check(kernel_init(&platform_module, &device_module, nullptr) == ERROR_NONE);
+    // HAL compatibility module: it creates kernel driver wrappers for tt::hal::Device
+    check(module_parent_construct(&tactility_tests_module_parent) == ERROR_NONE);
+    check(module_set_parent(&hal_device_module, &tactility_tests_module_parent) == ERROR_NONE);
+    check(module_start(&hal_device_module) == ERROR_NONE);
+
     data->result = context.run();
 
     vTaskEndScheduler();
@@ -46,4 +67,6 @@ int main(int argc, char** argv) {
     assert(task_result == pdPASS);
 
     vTaskStartScheduler();
+
+    return data.result;
 }

Tests/Tactility/ObjectFileTest.cpp

@@ -56,8 +56,10 @@ TEST_CASE("Appending records to a file") {
     CHECK_EQ(reader.open(), true);
     CHECK_EQ(reader.hasNext(), true);
     CHECK_EQ(reader.readNext(&record_in), true);
+    CHECK_EQ(record_in.value, 0xAAAAAAAA);
     CHECK_EQ(reader.hasNext(), true);
     CHECK_EQ(reader.readNext(&record_in), true);
+    CHECK_EQ(record_in.value, 0xBBBBBBBB);
     CHECK_EQ(reader.hasNext(), false);
     reader.close();
 

Tests/TactilityKernel/CMakeLists.txt

@@ -11,4 +11,8 @@ target_include_directories(TactilityKernelTests PRIVATE ${DOCTESTINC})
 
 add_test(NAME TactilityKernelTests COMMAND TactilityKernelTests)
 
-target_link_libraries(TactilityKernelTests PUBLIC TactilityKernel)
+target_link_libraries(TactilityKernelTests PUBLIC
+    TactilityKernel
+    PlatformPosix
+    hal-device
+)

Tests/TactilityKernel/DeviceTest.cpp

@@ -177,7 +177,7 @@ TEST_CASE("device_is_ready should return true only when it is started") {
 
     Device device = { 0 };
 
-    CHECK_EQ(driver_construct(&driver), ERROR_NONE);
+    CHECK_EQ(driver_construct_add(&driver), ERROR_NONE);
     CHECK_EQ(device_construct(&device), ERROR_NONE);
 
     CHECK_EQ(device.internal.state.started, false);
@@ -192,6 +192,6 @@ TEST_CASE("device_is_ready should return true only when it is started") {
     CHECK_EQ(device_remove(&device), ERROR_NONE);
     CHECK_EQ(device.internal.state.started, false);
 
-    CHECK_EQ(driver_destruct(&driver), ERROR_NONE);
     CHECK_EQ(device_destruct(&device), ERROR_NONE);
+    CHECK_EQ(driver_remove_destruct(&driver), ERROR_NONE);
 }

Tests/TactilityKernel/DriverIntegrationTest.cpp

@@ -55,7 +55,7 @@ TEST_CASE("driver with with start success and stop success should start and stop
         .parent = nullptr,
     };
 
-    CHECK_EQ(driver_construct(&integration_driver), ERROR_NONE);
+    CHECK_EQ(driver_construct_add(&integration_driver), ERROR_NONE);
 
     CHECK_EQ(device_construct(&integration_device), ERROR_NONE);
     device_add(&integration_device);
@@ -68,5 +68,5 @@ TEST_CASE("driver with with start success and stop success should start and stop
     CHECK_EQ(device_remove(&integration_device), ERROR_NONE);
     CHECK_EQ(device_destruct(&integration_device), ERROR_NONE);
 
-    CHECK_EQ(driver_destruct(&integration_driver), ERROR_NONE);
+    CHECK_EQ(driver_remove_destruct(&integration_driver), ERROR_NONE);
 }

Tests/TactilityKernel/DriverTest.cpp

@@ -14,7 +14,9 @@ TEST_CASE("driver_construct and driver_destruct should set and unset the correct
     driver.owner = &module;
 
     CHECK_EQ(driver_construct(&driver), ERROR_NONE);
+    CHECK_EQ(driver_add(&driver), ERROR_NONE);
     CHECK_NE(driver.driver_private, nullptr);
+    CHECK_EQ(driver_remove(&driver), ERROR_NONE);
     CHECK_EQ(driver_destruct(&driver), ERROR_NONE);
     CHECK_EQ(driver.driver_private, nullptr);
 }
@@ -62,10 +64,12 @@ TEST_CASE("driver_find should only find a compatible driver when the driver was
     CHECK_EQ(found_driver, nullptr);
 
     CHECK_EQ(driver_construct(&driver), ERROR_NONE);
+    CHECK_EQ(driver_add(&driver), ERROR_NONE);
 
     found_driver = driver_find_compatible("test_compatible");
     CHECK_EQ(found_driver, &driver);
 
+    CHECK_EQ(driver_remove(&driver), ERROR_NONE);
     CHECK_EQ(driver_destruct(&driver), ERROR_NONE);
 
     found_driver = driver_find_compatible("test_compatible");

Tests/TactilityKernel/Main.cpp

@@ -3,6 +3,7 @@
 #include <cassert>
 
 #include <tactility/freertos/task.h>
+#include <tactility/kernel_init.h>
 
 typedef struct {
     int argc;
@@ -10,6 +11,11 @@ typedef struct {
     int result;
 } TestTaskData;
 
+extern "C" {
+// From the relevant platform
+extern struct Module platform_module;
+}
+
 void test_task(void* parameter) {
     auto* data = (TestTaskData*)parameter;
 
@@ -20,6 +26,8 @@ void test_task(void* parameter) {
     // overrides
     context.setOption("no-breaks", true); // don't break in the debugger when assertions fail
 
+    check(kernel_init(&platform_module, nullptr, nullptr) == ERROR_NONE);
+
     data->result = context.run();
 
     vTaskEndScheduler();