Tab5 power expander driver and devicetree parsing improvements (#507)

* **New Features**
  * PI4IOE5V6408 I2C I/O expander driver with public GPIO APIs
  * CLI tool to list devicetree dependencies

* **Device Tree Updates**
  * M5Stack Tab5 configured with two I2C IO expanders; PI4IOE5V6408 binding added

* **Build / Tooling**
  * Devicetree code generation integrated into build; generated artifacts and dynamic dependency resolution exposed

* **Refactor**
  * Kernel/run APIs updated to accept a null‑terminated devicetree modules array; many module symbols renamed

* **Documentation**
  * Added README and Apache‑2.0 license for new driver module

Buildscripts/DevicetreeCompiler/dependencies.py

@@ -0,0 +1,35 @@
+import sys
+import os
+
+from source.printing import print_error
+from source.config import parse_config
+
+def print_help():
+    print("Usage: python dependencies.py [path]\n")
+    print("\t[in_file]                 the path where the root devicetree.yaml file is")
+
+if __name__ == "__main__":
+    if "--help" in sys.argv:
+        print_help()
+        sys.exit()
+    args = [a for a in sys.argv[1:] if not a.startswith("--")]
+    if len(args) < 1:
+        print_error("Missing argument")
+        print_help()
+        sys.exit(1)
+
+    yaml_directory = args[0]
+    
+    if not os.path.exists(yaml_directory):
+        print_error(f"Path not found: {yaml_directory}")
+        sys.exit(1)
+
+    config = parse_config(yaml_directory, os.getcwd())
+
+    # Device module is added first because it's started first:
+    # It creates the root device, so it must exist before its children.
+    device_dependency = os.path.basename(os.path.normpath(yaml_directory))
+    print(device_dependency)
+    for dependency in config.dependencies:
+        dependency_name = os.path.basename(os.path.normpath(dependency))
+        print(dependency_name)

Buildscripts/DevicetreeCompiler/source/generator.py

@@ -212,7 +212,7 @@ def gather_devices(device: Device, output: list[Device]):
     for child_device in device.devices:
         gather_devices(child_device, output)
 
-def generate_devicetree_c(filename: str, items: list[object], bindings: list[Binding], verbose: bool):
+def generate_devicetree_c(filename: str, items: list[object], bindings: list[Binding], config, verbose: bool):
     # Create a cache for looking up device names and aliases easily
     # We still want to traverse it as a tree during code generation because of parent-setting
     devices = list()
@@ -225,6 +225,7 @@ def generate_devicetree_c(filename: str, items: list[object], bindings: list[Bin
         // Default headers
         #include <tactility/device.h>
         #include <tactility/dts.h>
+        #include <tactility/module.h>
         // DTS headers
         '''))
 
@@ -246,6 +247,25 @@ def generate_devicetree_c(filename: str, items: list[object], bindings: list[Bin
                 write_device_list_entry(file, item, bindings, verbose)
         file.write("\tDTS_DEVICE_TERMINATOR\n")
         file.write("};\n")
+        # Gather module symbols
+        module_symbol_names = []
+        for dependency in config.dependencies:
+            dependency_name = os.path.basename(os.path.normpath(dependency))
+            module_symbol_name = f"{dependency_name.replace('-', '_')}"
+            if not module_symbol_name.endswith("_module"):
+                module_symbol_name += "_module"
+            module_symbol_names.append(module_symbol_name)
+        file.write("\n")
+        # Forward declaration of symbol variables
+        for symbol in module_symbol_names:
+            file.write(f"extern struct Module {symbol};\n")
+        file.write("\n")
+        # Create array of symbol variables
+        file.write("struct Module* dts_modules[] = {\n")
+        for symbol in module_symbol_names:
+            file.write(f"\t&{symbol},\n")
+        file.write("\tNULL\n")
+        file.write("};\n")
 
 def generate_devicetree_h(filename: str):
     with open(filename, "w") as file:
@@ -258,17 +278,21 @@ def generate_devicetree_h(filename: str):
         extern "C" {
         #endif
         
+        // Array of device tree modules terminated with DTS_MODULE_TERMINATOR
         extern struct DtsDevice dts_devices[];
         
+        // Array of module symbols terminated with NULL
+        extern struct Module* dts_modules[];
+        
         #ifdef __cplusplus
         }
         #endif
         '''))
 
-def generate(output_path: str, items: list[object], bindings: list[Binding], verbose: bool):
+def generate(output_path: str, items: list[object], bindings: list[Binding], config, 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)
+    generate_devicetree_c(devicetree_c_filename, items, bindings, config, verbose)
     devicetree_h_filename = os.path.join(output_path, "devicetree.h")
     generate_devicetree_h(devicetree_h_filename)

Buildscripts/DevicetreeCompiler/source/main.py

@@ -46,7 +46,7 @@ def main(config_path: str, output_path: str, verbose: bool) -> int:
         if verbose:
             for binding in bindings:
                 pprint(binding)
-        generate(output_path, transformed, bindings, verbose)
+        generate(output_path, transformed, bindings, config, verbose)
         return 0
     except DevicetreeException as caught:
         print("\033[31mError: ", caught, "\033[0m")

CMakeLists.txt

@@ -99,9 +99,6 @@ if (NOT DEFINED ENV{ESP_IDF_VERSION})
     set(FREERTOS_PORT GCC_POSIX CACHE STRING "")
     add_subdirectory(Libraries/FreeRTOS-Kernel)
     target_compile_definitions(freertos_kernel PUBLIC "projCOVERAGE_TEST=0")
-    target_include_directories(freertos_kernel
-        PUBLIC Devices/Simulator/Source # for FreeRTOSConfig.h
-    )
 
     # EmbedTLS
     set(ENABLE_TESTING OFF)

Devices/btt-panda-touch/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module btt_panda_touch_module = {
-struct Module device_module = {
     .name = "btt-panda-touch",
     .start = start,
     .stop = stop,

Devices/cyd-2432s024c/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module cyd_2432s024c_module = {
-struct Module device_module = {
     .name = "cyd-2432s024c",
     .start = start,
     .stop = stop,

Devices/cyd-2432s028r/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module cyd_2432s028r_module = {
-struct Module device_module = {
     .name = "cyd-2432s028r",
     .start = start,
     .stop = stop,

Devices/cyd-2432s028rv3/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module cyd_2432s028rv3_module = {
-struct Module device_module = {
     .name = "cyd-2432s028rv3",
     .start = start,
     .stop = stop,

Devices/cyd-2432s032c/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module cyd_2432s032c_module = {
-struct Module device_module = {
     .name = "cyd-2432s032c",
     .start = start,
     .stop = stop,

Devices/cyd-4848s040c/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module cyd_4848s040c_module = {
-struct Module device_module = {
     .name = "cyd-4848s040c",
     .start = start,
     .stop = stop,

Devices/cyd-8048s043c/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module cyd_8048s043c_module = {
-struct Module device_module = {
     .name = "cyd-8048s043c",
     .start = start,
     .stop = stop,

Devices/cyd-e32r28t/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module cyd_e32r28t_module = {
-struct Module device_module = {
     .name = "cyd-e32r28t",
     .start = start,
     .stop = stop,

Devices/cyd-e32r32p/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module cyd_e32r32p_module = {
-struct Module device_module = {
     .name = "cyd-e32r32p",
     .start = start,
     .stop = stop,

Devices/elecrow-crowpanel-advance-28/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module elecrow_crowpanel_advance_28_module = {
-struct Module device_module = {
     .name = "elecrow-crowpanel-advance-28",
     .start = start,
     .stop = stop,

Devices/elecrow-crowpanel-advance-35/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module elecrow_crowpanel_advance_35_module = {
-struct Module device_module = {
     .name = "elecrow-crowpanel-advance-35",
     .start = start,
     .stop = stop,

Devices/elecrow-crowpanel-advance-50/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module elecrow_crowpanel_advance_50_module = {
-struct Module device_module = {
     .name = "elecrow-crowpanel-advance-50",
     .start = start,
     .stop = stop,

Devices/elecrow-crowpanel-basic-28/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module elecrow_crowpanel_basic_28_module = {
-struct Module device_module = {
     .name = "elecrow-crowpanel-basic-28",
     .start = start,
     .stop = stop,

Devices/elecrow-crowpanel-basic-35/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module elecrow_crowpanel_basic_35_module = {
-struct Module device_module = {
     .name = "elecrow-crowpanel-basic-35",
     .start = start,
     .stop = stop,

Devices/elecrow-crowpanel-basic-50/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module elecrow_crowpanel_basic_50_module = {
-struct Module device_module = {
     .name = "elecrow-crowpanel-basic-50",
     .start = start,
     .stop = stop,

Devices/generic-esp32/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module generic_esp32_module = {
-struct Module device_module = {
     .name = "generic-esp32",
     .start = start,
     .stop = stop,

Devices/generic-esp32c6/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module generic_esp32c6_module = {
-struct Module device_module = {
     .name = "generic-esp32c6",
     .start = start,
     .stop = stop,

Devices/generic-esp32p4/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module generic_esp32p4_module = {
-struct Module device_module = {
     .name = "generic-esp32p4",
     .start = start,
     .stop = stop,

Devices/generic-esp32s3/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module generic_esp32s3_module = {
-struct Module device_module = {
     .name = "generic-esp32s3",
     .start = start,
     .stop = stop,

Devices/guition-jc1060p470ciwy/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module guition_jc1060p470ciwy_module = {
-struct Module device_module = {
     .name = "guition-jc1060p470ciwy",
     .start = start,
     .stop = stop,

Devices/guition-jc2432w328c/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module guition_jc2432w328c_module = {
-struct Module device_module = {
     .name = "guition-jc2432w328c",
     .start = start,
     .stop = stop,

Devices/guition-jc3248w535c/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module guition_jc3248w535c_module = {
-struct Module device_module = {
     .name = "guition-jc3248w535c",
     .start = start,
     .stop = stop,

Devices/guition-jc8048w550c/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module guition_jc8048w550c_module = {
-struct Module device_module = {
     .name = "guition-jc8048w550c",
     .start = start,
     .stop = stop,

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

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module heltec_wifi_lora_32_v3_module = {
-struct Module device_module = {
     .name = "heltec-wifi-lora-32-v3",
     .start = start,
     .stop = stop,

Devices/lilygo-tdeck/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module lilygo_tdeck_module = {
-struct Module device_module = {
     .name = "lilygo-tdeck",
     .start = start,
     .stop = stop,

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

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module lilygo_tdisplay_s3_module = {
-struct Module device_module = {
     .name = "lilygo-tdisplay-s3",
     .start = start,
     .stop = stop,

Devices/lilygo-tdisplay/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module lilygo_tdisplay_module = {
-struct Module device_module = {
     .name = "lilygo-tdisplay",
     .start = start,
     .stop = stop,

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

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module lilygo_tdongle_s3_module = {
-struct Module device_module = {
     .name = "lilygo-tdongle-s3",
     .start = start,
     .stop = stop,

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

@@ -20,8 +20,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module lilygo_tlora_pager_module = {
-struct Module device_module = {
     .name = "lilygo-tlora-pager",
     .start = start,
     .stop = stop,

Devices/m5stack-cardputer-adv/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module m5stack_cardputer_adv_module = {
-struct Module device_module = {
     .name = "m5stack-cardputer-adv",
     .start = start,
     .stop = stop,

Devices/m5stack-cardputer/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module m5stack_cardputer_module = {
-struct Module device_module = {
     .name = "m5stack-cardputer",
     .start = start,
     .stop = stop,

Devices/m5stack-core2/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module m5stack_core2_module = {
-struct Module device_module = {
     .name = "m5stack-core2",
     .start = start,
     .stop = stop,

Devices/m5stack-cores3/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module m5stack_cores3_module = {
-struct Module device_module = {
     .name = "m5stack-cores3",
     .start = start,
     .stop = stop,

Devices/m5stack-papers3/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module m5stack_papers3_module = {
-struct Module device_module = {
     .name = "m5stack-papers3",
     .start = start,
     .stop = stop,

Devices/m5stack-stickc-plus/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module m5stack_stickc_plus_module = {
-struct Module device_module = {
     .name = "m5stack-stickc-plus",
     .start = start,
     .stop = stop,

Devices/m5stack-stickc-plus2/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module m5stack_stickc_plus2_module = {
-struct Module device_module = {
     .name = "m5stack-stickc-plus2",
     .start = start,
     .stop = stop,

Devices/m5stack-tab5/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_lvgl_port esp_lcd EspLcdCompat esp_lcd_ili9881c GT911 PwmBacklight driver vfs fatfs
+    REQUIRES Tactility esp_lvgl_port esp_lcd EspLcdCompat esp_lcd_ili9881c GT911 PwmBacklight driver vfs fatfs pi4ioe5v6408-module
 )

Devices/m5stack-tab5/Source/Configuration.cpp

@@ -6,6 +6,7 @@
 
 #include <Tactility/hal/Configuration.h>
 #include <Tactility/hal/i2c/I2c.h>
+#include <drivers/pi4ioe5v6408.h>
 
 using namespace tt::hal;
 
@@ -18,9 +19,11 @@ static DeviceVector createDevices() {
     };
 }
 
-static error_t initPower(::Device* i2c_controller) {
+static error_t initPower(::Device* io_expander0, ::Device* io_expander1) {
+    constexpr TickType_t i2c_timeout = pdMS_TO_TICKS(10);
+
     /*
-     PI4IOE5V6408-1 (0x43)
+     PI4IOE5V6408-0 (0x43)
      - Bit 0: RF internal/external switch
      - Bit 1: Speaker enable
      - Bit 2: External 5V bus enable
@@ -29,8 +32,18 @@ static error_t initPower(::Device* i2c_controller) {
      - Bit 5: Touch reset
      - Bit 6: Camera reset
      - Bit 7: Headphone detect
+     */
 
-     PI4IOE5V6408-2 (0x44)
+    check(pi4ioe5v6408_set_direction(io_expander0, 0b01111111, i2c_timeout) == ERROR_NONE);
+    check(pi4ioe5v6408_set_output_level(io_expander0, 0b01000110, i2c_timeout) == ERROR_NONE);
+    check(pi4ioe5v6408_set_output_high_impedance(io_expander0, 0b00000000, i2c_timeout) == ERROR_NONE);
+    check(pi4ioe5v6408_set_pull_select(io_expander0, 0b01111111, i2c_timeout) == ERROR_NONE);
+    check(pi4ioe5v6408_set_pull_enable(io_expander0, 0b01111111, i2c_timeout) == ERROR_NONE);
+    vTaskDelay(pdMS_TO_TICKS(10));
+    check(pi4ioe5v6408_set_output_level(io_expander0, 0b01110110, i2c_timeout) == ERROR_NONE);
+
+    /*
+     PI4IOE5V6408-1 (0x44)
      - Bit 0: C6 WLAN enable
      - Bit 1: /
      - Bit 2: /
@@ -41,57 +54,18 @@ static error_t initPower(::Device* i2c_controller) {
      - Bit 7: IP2326: CHG_EN
     */
 
-    // Init byte arrays adapted from https://github.com/m5stack/M5GFX/blob/03565ccc96cb0b73c8b157f5ec3fbde439b034ad/src/M5GFX.cpp
+    check(pi4ioe5v6408_set_direction(io_expander1, 0b10111001, i2c_timeout) == ERROR_NONE);
-    static constexpr uint8_t reg_data_io1_1[] = {
+    check(pi4ioe5v6408_set_output_high_impedance(io_expander1, 0b00000110, i2c_timeout) == ERROR_NONE);
-        0x03, 0b01111111,   // PI4IO_REG_IO_DIR
+    check(pi4ioe5v6408_set_pull_select(io_expander1, 0b10111001, i2c_timeout) == ERROR_NONE);
-        0x05, 0b01000110,   // PI4IO_REG_OUT_SET (bit4=LCD Reset, bit5=GT911 TouchReset -> LOW)
+    check(pi4ioe5v6408_set_pull_enable(io_expander1, 0b11111001, i2c_timeout) == ERROR_NONE);
-        0x07, 0b00000000,   // PI4IO_REG_OUT_H_IM
+    check(pi4ioe5v6408_set_input_default_level(io_expander1, 0b01000000, i2c_timeout) == ERROR_NONE);
-        0x0D, 0b01111111,   // PI4IO_REG_PULL_SEL
+    check(pi4ioe5v6408_set_interrupt_mask(io_expander1, 0b10111111, i2c_timeout) == ERROR_NONE);
-        0x0B, 0b01111111,   // PI4IO_REG_PULL_EN
+    check(pi4ioe5v6408_set_output_level(io_expander1, 0b10001001, i2c_timeout) == ERROR_NONE);
-    };
-
-    static constexpr uint8_t reg_data_io1_2[] = {
-        0x05, 0b01110110,   // PI4IO_REG_OUT_SET (bit4=LCD Reset, bit5=GT911 TouchReset -> HIGH)
-    };
-
-    static constexpr uint8_t reg_data_io2[] = {
-        0x03, 0b10111001,   // PI4IO_REG_IO_DIR
-        0x07, 0b00000110,   // PI4IO_REG_OUT_H_IM
-        0x0D, 0b10111001,   // PI4IO_REG_PULL_SEL
-        0x0B, 0b11111001,   // PI4IO_REG_PULL_EN
-        0x09, 0b01000000,   // PI4IO_REG_IN_DEF_STA
-        0x11, 0b10111111,   // PI4IO_REG_INT_MASK
-        0x05, 0b10001001,   // PI4IO_REG_OUT_SET (enable WiFi, USB-A 5V and CHG_EN)
-    };
-
-    constexpr auto IO_EXPANDER1_ADDRESS = 0x43;
-    auto error = i2c_controller_write_register_array(i2c_controller, IO_EXPANDER1_ADDRESS, reg_data_io1_1, sizeof(reg_data_io1_1), pdMS_TO_TICKS(100));
-    if (error != ERROR_NONE) {
-        LOG_E(TAG, "IO expander 1 init failed in phase 1");
-        return ERROR_UNDEFINED;
-    }
-
-    constexpr auto IO_EXPANDER2_ADDRESS = 0x44;
-    error = i2c_controller_write_register_array(i2c_controller, IO_EXPANDER2_ADDRESS, reg_data_io2, sizeof(reg_data_io2), pdMS_TO_TICKS(100));
-    if (error != ERROR_NONE) {
-        LOG_E(TAG, "IO expander 2 init failed");
-        return ERROR_UNDEFINED;
-    }
-
-    // The M5Stack code applies this, but it's not known why
-    // TODO: Remove and test it extensively
-    tt::kernel::delayTicks(10);
-
-    error = i2c_controller_write_register_array(i2c_controller, IO_EXPANDER1_ADDRESS, reg_data_io1_2, sizeof(reg_data_io1_2), pdMS_TO_TICKS(100));
-    if (error != ERROR_NONE) {
-        LOG_E(TAG, "IO expander 1 init failed in phase 2");
-        return ERROR_UNDEFINED;
-    }
 
     return ERROR_NONE;
 }
 
-static error_t initSound(::Device* i2c_controller) {
+static error_t initSound(::Device* i2c_controller, ::Device* io_expander0 = nullptr) {
     // Init data from M5Unified:
     // https://github.com/m5stack/M5Unified/blob/master/src/M5Unified.cpp
     static constexpr uint8_t ES8388_I2C_ADDR = 0x10;
@@ -139,13 +113,15 @@ static error_t initSound(::Device* i2c_controller) {
         return error;
     }
 
-    constexpr auto IO_EXPANDER1_ADDRESS = 0x43;
+    uint8_t output_level = 0;
-    constexpr auto AMP_REGISTER = 0x05;
+    if (pi4ioe5v6408_get_output_level(io_expander0, &output_level, pdMS_TO_TICKS(100)) != ERROR_NONE) {
-    // Note: to disable the amplifier, reset the bits
+        LOG_E(TAG, "Failed to read power level: %s", error_to_string(error));
-    error = i2c_controller_register8_set_bits(i2c_controller, IO_EXPANDER1_ADDRESS, AMP_REGISTER, 0b00000010, pdMS_TO_TICKS(100));
+        return ERROR_RESOURCE;
-    if (error != ERROR_NONE) {
+    }
+
+    if (pi4ioe5v6408_set_output_level(io_expander0, output_level | 0b00000010, pdMS_TO_TICKS(100)) != ERROR_NONE) {
         LOG_E(TAG, "Failed to enable amplifier: %s", error_to_string(error));
-        return error;
+        return ERROR_RESOURCE;
     }
 
     return ERROR_NONE;
@@ -155,12 +131,13 @@ static bool initBoot() {
     auto* i2c0 = device_find_by_name("i2c0");
     check(i2c0, "i2c0 not found");
 
-    auto error = initPower(i2c0);
+    auto* io_expander0 = device_find_by_name("io_expander0");
-    if (error != ERROR_NONE) {
+    auto* io_expander1 = device_find_by_name("io_expander1");
-        return false;
+    check(i2c0, "i2c0 not found");
-    }
 
-    error = initSound(i2c0);
+    initPower(io_expander0, io_expander1);
+
+    error_t error = initSound(i2c0, io_expander0);
     if (error != ERROR_NONE) {
         LOG_E(TAG, "Failed to enable ES8388");
     }

Devices/m5stack-tab5/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+Module m5stack_tab5_module = {
-struct Module device_module = {
     .name = "m5stack-tab5",
     .start = start,
     .stop = stop,

Devices/m5stack-tab5/devicetree.yaml

@@ -1,3 +1,4 @@
 dependencies:
   - Platforms/platform-esp32
+  - Drivers/pi4ioe5v6408-module
 dts: m5stack,tab5.dts

Devices/m5stack-tab5/m5stack,tab5.dts

@@ -5,6 +5,7 @@
 #include <tactility/bindings/esp32_i2c.h>
 #include <tactility/bindings/esp32_i2s.h>
 #include <tactility/bindings/esp32_spi.h>
+#include <bindings/pi4ioe5v6408.h>
 
 / {
 	compatible = "root";
@@ -21,6 +22,36 @@
 		clock-frequency = <400000>;
 		pin-sda = <&gpio0 31 GPIO_FLAG_NONE>;
 		pin-scl = <&gpio0 32 GPIO_FLAG_NONE>;
+
+		/*
+		 - Bit 0: RF internal/external switch
+		 - Bit 1: Speaker enable
+		 - Bit 2: External 5V bus enable
+		 - Bit 3: /
+		 - Bit 4: LCD reset
+		 - Bit 5: Touch reset
+		 - Bit 6: Camera reset
+		 - Bit 7: Headphone detect
+		 */
+		io_expander0 {
+			compatible = "diodes,pi4ioe5v6408";
+			reg = <0x43>;
+		};
+
+		/*
+		 - Bit 0: C6 WLAN enable
+		 - Bit 1: /
+		 - Bit 2: /
+		 - Bit 3: USB-A 5V enable
+		 - Bit 4: Device power: PWROFF_PLUSE
+		 - Bit 5: IP2326: nCHG_QC_EN
+		 - Bit 6: IP2326: CHG_STAT_LED
+		 - Bit 7: IP2326: CHG_EN
+		*/
+		io_expander1 {
+			compatible = "diodes,pi4ioe5v6408";
+			reg = <0x44>;
+		};
 	};
 
 	i2c_port_a: i2c1 {

Devices/simulator/CMakeLists.txt

@@ -5,20 +5,20 @@ if (NOT DEFINED ENV{ESP_IDF_VERSION})
     file(GLOB_RECURSE SOURCES "Source/*.c*")
     file(GLOB_RECURSE HEADERS "Source/*.h*")
 
-    add_library(Simulator OBJECT)
+    add_library(simulator OBJECT)
 
-    target_sources(Simulator
+    target_sources(simulator
         PRIVATE ${SOURCES}
         PUBLIC ${HEADERS}
     )
 
-    target_link_libraries(Simulator
+    target_link_libraries(simulator
         PRIVATE Tactility
         PRIVATE TactilityCore
         PRIVATE lvgl
         PRIVATE SDL2-static
     )
 
-    target_link_libraries(Simulator PRIVATE ${SDL2_LIBRARIES})
+    target_link_libraries(simulator PRIVATE ${SDL2_LIBRARIES})
 
 endif()

Devices/simulator/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module simulator_module = {
-struct Module device_module = {
     .name = "simulator",
     .start = start,
     .stop = stop,

Devices/unphone/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module unphone_module = {
-struct Module device_module = {
     .name = "unphone",
     .start = start,
     .stop = stop,

Devices/waveshare-esp32-s3-geek/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module waveshare_esp32_s3_geek_module = {
-struct Module device_module = {
     .name = "waveshare-esp32-s3-geek",
     .start = start,
     .stop = stop,

Devices/waveshare-s3-lcd-13/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module waveshare_s3_lcd_13_module = {
-struct Module device_module = {
     .name = "waveshare-s3-lcd-13",
     .start = start,
     .stop = stop,

Devices/waveshare-s3-touch-lcd-128/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module waveshare_s3_touch_lcd_128_module = {
-struct Module device_module = {
     .name = "waveshare-s3-touch-lcd-128",
     .start = start,
     .stop = stop,

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

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module waveshare_s3_touch_lcd_147_module = {
-struct Module device_module = {
     .name = "waveshare-s3-touch-lcd-147",
     .start = start,
     .stop = stop,

Devices/waveshare-s3-touch-lcd-43/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module waveshare_s3_touch_lcd_43_module = {
-struct Module device_module = {
     .name = "waveshare-s3-touch-lcd-43",
     .start = start,
     .stop = stop,

Devices/wireless-tag-wt32-sc01-plus/Source/module.cpp

@@ -12,8 +12,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-/** @warning The variable name must be exactly "device_module" */
+struct Module wireless_tag_wt32_sc01_plus_module = {
-struct Module device_module = {
     .name = "wireless-tag-wt32-sc01-plus",
     .start = start,
     .stop = stop,

Drivers/pi4ioe5v6408-module/CMakeLists.txt

@@ -0,0 +1,11 @@
+cmake_minimum_required(VERSION 3.20)
+
+include("${CMAKE_CURRENT_LIST_DIR}/../../Buildscripts/module.cmake")
+
+file(GLOB_RECURSE SOURCE_FILES "source/*.c*")
+
+tactility_add_module(pi4ioe5v6408-module
+    SRCS ${SOURCE_FILES}
+    INCLUDE_DIRS include/
+    REQUIRES TactilityKernel
+)

Drivers/pi4ioe5v6408-module/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
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+
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+
+“You” (or “Your”) shall mean an individual or Legal Entity exercising
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+“Work” shall mean the work of authorship, whether in Source or Object form, made
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+“Contributor” shall mean Licensor and any individual or Legal Entity on behalf
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+#### 2. Grant of Copyright License
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+

Drivers/pi4ioe5v6408-module/README.md

@@ -0,0 +1,8 @@
+# PI4IOE5V6408 I/O expander
+
+A driver for the `PI4IOE5V6408` low-voltage translating 8-bit I2C-bus I/O expander by Diodes Incorporated.
+
+See https://www.diodes.com/part/view/PI4IOE5V6408
+And: https://www.digikey.com/htmldatasheets/production/3031904/0/0/1/pi4ioe5v6408.html
+
+License: [Apache v2.0](LICENSE-Apache-2.0.md)

Drivers/pi4ioe5v6408-module/bindings/diodes,pi4ioe5v6408.yaml

@@ -0,0 +1,5 @@
+description: Diodes Incorporated PI4IOE5V6408 low-voltage translating 8-bit I2C-bus I/O expander
+
+include: ["i2c-device.yaml"]
+
+compatible: "diodes,pi4ioe5v6408"

Drivers/pi4ioe5v6408-module/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+bindings: bindings

Drivers/pi4ioe5v6408-module/include/bindings/pi4ioe5v6408.h

@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <tactility/bindings/bindings.h>
+#include <drivers/pi4ioe5v6408.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+DEFINE_DEVICETREE(pi4ioe5v6408, struct Pi4ioe5v6408Config)
+
+#ifdef __cplusplus
+}
+#endif

Drivers/pi4ioe5v6408-module/include/drivers/pi4ioe5v6408.h

@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <stdint.h>
+#include <tactility/error.h>
+#include <tactility/freertos/freertos.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct Device;
+
+struct Pi4ioe5v6408Config {
+    /** Address on bus */
+    uint8_t address;
+};
+
+error_t pi4ioe5v6408_set_direction(struct Device* device, uint8_t bits, TickType_t timeout);
+
+error_t pi4ioe5v6408_set_output_level(struct Device* device, uint8_t bits, TickType_t timeout);
+
+error_t pi4ioe5v6408_get_output_level(struct Device* device, uint8_t* bits, TickType_t timeout);
+
+error_t pi4ioe5v6408_set_output_high_impedance(struct Device* device, uint8_t bits, TickType_t timeout);
+
+error_t pi4ioe5v6408_set_input_default_level(struct Device* device, uint8_t bits, TickType_t timeout);
+
+error_t pi4ioe5v6408_set_pull_enable(struct Device* device, uint8_t bits, TickType_t timeout);
+
+error_t pi4ioe5v6408_set_pull_select(struct Device* device, uint8_t bits, TickType_t timeout);
+
+error_t pi4ioe5v6408_get_input_level(struct Device* device, uint8_t* bits, TickType_t timeout);
+
+error_t pi4ioe5v6408_set_interrupt_mask(struct Device* device, uint8_t bits, TickType_t timeout);
+
+error_t pi4ioe5v6408_get_interrupt_level(struct Device* device, uint8_t* bits, TickType_t timeout);
+
+#ifdef __cplusplus
+}
+#endif

Drivers/pi4ioe5v6408-module/include/pi4ioe5v6408_module.h

@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <tactility/module.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern struct Module pi4ioe5v6408_module;
+
+#ifdef __cplusplus
+}
+#endif

Drivers/pi4ioe5v6408-module/source/module.cpp

@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <tactility/check.h>
+#include <tactility/driver.h>
+#include <tactility/module.h>
+
+extern "C" {
+
+extern Driver pi4ioe5v6408_driver;
+extern const ModuleSymbol pi4ioe5v6408_module_symbols[];
+
+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(&pi4ioe5v6408_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_destruct(&pi4ioe5v6408_driver) == ERROR_NONE);
+    return ERROR_NONE;
+}
+
+Module pi4ioe5v6408_module = {
+    .name = "pi4ioe5v6408",
+    .start = start,
+    .stop = stop,
+    .symbols = pi4ioe5v6408_module_symbols,
+    .internal = nullptr
+};
+
+}

Drivers/pi4ioe5v6408-module/source/pi4ioe5v6408.cpp

@@ -0,0 +1,100 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <drivers/pi4ioe5v6408.h>
+#include <pi4ioe5v6408_module.h>
+#include <tactility/device.h>
+#include <tactility/driver.h>
+#include <tactility/drivers/i2c_controller.h>
+#include <tactility/log.h>
+
+#define TAG "PI4IOE5V6408"
+
+#define GET_CONFIG(device) (static_cast<const Pi4ioe5v6408Config*>((device)->config))
+
+constexpr auto PI4_REGISTER_DIRECTION = 0x03;
+constexpr auto PI4_REGISTER_OUTPUT_LEVEL = 0x05;
+constexpr auto PI4_REGISTER_OUTPUT_HIGH_IMPEDANCE = 0x07;
+constexpr auto PI4_REGISTER_INPUT_DEFAULT_LEVEL = 0x09;
+constexpr auto PI4_REGISTER_PULL_ENABLE = 0x0B;
+constexpr auto PI4_REGISTER_PULL_SELECT = 0x0D;
+constexpr auto PI4_REGISTER_INPUT_LEVEL = 0x0F;
+constexpr auto PI4_REGISTER_INTERRUPT_MASK = 0x11;
+constexpr auto PI4_REGISTER_INTERRUPT_LEVEL = 0x13;
+
+static error_t start(Device* device) {
+    auto* parent = device_get_parent(device);
+    if (device_get_type(parent) != &I2C_CONTROLLER_TYPE) {
+        LOG_E(TAG, "Parent device is not I2C");
+        return ERROR_RESOURCE;
+    }
+    LOG_I(TAG, "Started PI4IOE5V6408 device %s", device->name);
+    return ERROR_NONE;
+}
+
+static error_t stop(Device* device) {
+    return ERROR_NONE;
+}
+
+extern "C" {
+
+error_t pi4ioe5v6408_set_direction(Device* device, uint8_t bits, TickType_t timeout) {
+    auto* parent = device_get_parent(device);
+    return i2c_controller_register8_set(parent, GET_CONFIG(device)->address, PI4_REGISTER_DIRECTION, bits, timeout);
+}
+
+error_t pi4ioe5v6408_set_output_level(Device* device, uint8_t bits, TickType_t timeout) {
+    auto* parent = device_get_parent(device);
+    return i2c_controller_register8_set(parent, GET_CONFIG(device)->address, PI4_REGISTER_OUTPUT_LEVEL, bits, timeout);
+}
+
+error_t pi4ioe5v6408_get_output_level(Device* device, uint8_t* bits, TickType_t timeout) {
+    auto* parent = device_get_parent(device);
+    return i2c_controller_register8_get(parent, GET_CONFIG(device)->address, PI4_REGISTER_OUTPUT_LEVEL, bits, timeout);
+}
+
+error_t pi4ioe5v6408_set_output_high_impedance(struct Device* device, uint8_t bits, TickType_t timeout) {
+    auto* parent = device_get_parent(device);
+    return i2c_controller_register8_set(parent, GET_CONFIG(device)->address, PI4_REGISTER_OUTPUT_HIGH_IMPEDANCE, bits, timeout);
+}
+
+error_t pi4ioe5v6408_set_input_default_level(struct Device* device, uint8_t bits, TickType_t timeout) {
+    auto* parent = device_get_parent(device);
+    return i2c_controller_register8_set(parent, GET_CONFIG(device)->address, PI4_REGISTER_INPUT_DEFAULT_LEVEL, bits, timeout);
+}
+
+error_t pi4ioe5v6408_set_pull_enable(struct Device* device, uint8_t bits, TickType_t timeout) {
+    auto* parent = device_get_parent(device);
+    return i2c_controller_register8_set(parent, GET_CONFIG(device)->address, PI4_REGISTER_PULL_ENABLE, bits, timeout);
+}
+
+error_t pi4ioe5v6408_set_pull_select(struct Device* device, uint8_t bits, TickType_t timeout) {
+    auto* parent = device_get_parent(device);
+    return i2c_controller_register8_set(parent, GET_CONFIG(device)->address, PI4_REGISTER_PULL_SELECT, bits, timeout);
+}
+
+error_t pi4ioe5v6408_get_input_level(struct Device* device, uint8_t* bits, TickType_t timeout) {
+    auto* parent = device_get_parent(device);
+    return i2c_controller_register8_get(parent, GET_CONFIG(device)->address, PI4_REGISTER_INPUT_LEVEL, bits, timeout);
+}
+
+error_t pi4ioe5v6408_set_interrupt_mask(struct Device* device, uint8_t bits, TickType_t timeout) {
+    auto* parent = device_get_parent(device);
+    return i2c_controller_register8_set(parent, GET_CONFIG(device)->address, PI4_REGISTER_INTERRUPT_MASK, bits, timeout);
+}
+
+error_t pi4ioe5v6408_get_interrupt_level(struct Device* device, uint8_t* bits, TickType_t timeout) {
+    auto* parent = device_get_parent(device);
+    return i2c_controller_register8_get(parent, GET_CONFIG(device)->address, PI4_REGISTER_INTERRUPT_LEVEL, bits, timeout);
+}
+
+Driver pi4ioe5v6408_driver = {
+    .name = "pi4ioe5v6408",
+    .compatible = (const char*[]) { "diodes,pi4ioe5v6408", nullptr},
+    .start_device = start,
+    .stop_device = stop,
+    .api = nullptr,
+    .device_type = nullptr,
+    .owner = &pi4ioe5v6408_module,
+    .internal = nullptr
+};
+
+}

Drivers/pi4ioe5v6408-module/source/symbols.c

@@ -0,0 +1,15 @@
+#include <drivers/pi4ioe5v6408.h>
+#include <tactility/module.h>
+
+const struct ModuleSymbol pi4ioe5v6408_module_symbols[] = {
+    DEFINE_MODULE_SYMBOL(pi4ioe5v6408_set_direction),
+    DEFINE_MODULE_SYMBOL(pi4ioe5v6408_set_output_level),
+    DEFINE_MODULE_SYMBOL(pi4ioe5v6408_set_output_high_impedance),
+    DEFINE_MODULE_SYMBOL(pi4ioe5v6408_set_input_default_level),
+    DEFINE_MODULE_SYMBOL(pi4ioe5v6408_set_pull_enable),
+    DEFINE_MODULE_SYMBOL(pi4ioe5v6408_set_pull_select),
+    DEFINE_MODULE_SYMBOL(pi4ioe5v6408_get_input_level),
+    DEFINE_MODULE_SYMBOL(pi4ioe5v6408_set_interrupt_mask),
+    DEFINE_MODULE_SYMBOL(pi4ioe5v6408_get_interrupt_level),
+    MODULE_SYMBOL_TERMINATOR
+};

Firmware/CMakeLists.txt

@@ -2,17 +2,47 @@ cmake_minimum_required(VERSION 3.20)
 
 file(GLOB_RECURSE SOURCE_FILES "Source/*.c*")
 
-# For Generate target below
+get_filename_component(PROJECT_ROOT "${CMAKE_CURRENT_LIST_DIR}/.." ABSOLUTE)
+
+# Get the project and device id
 if (DEFINED ENV{ESP_IDF_VERSION})
     include("../Buildscripts/device.cmake")
     init_tactility_globals("../sdkconfig")
     get_property(TACTILITY_DEVICE_PROJECT GLOBAL PROPERTY TACTILITY_DEVICE_PROJECT)
+    get_property(TACTILITY_DEVICE_ID GLOBAL PROPERTY TACTILITY_DEVICE_ID)
 else ()
     set(TACTILITY_DEVICE_ID simulator)
     set(COMPONENT_LIB FirmwareSim)
+    set(TACTILITY_DEVICE_PROJECT Simulator)
 endif ()
 
-set(DEVICETREE_LOCATION "${CMAKE_SOURCE_DIR}/Devices/${TACTILITY_DEVICE_ID}")
+set(DEVICETREE_LOCATION "${PROJECT_ROOT}/Devices/${TACTILITY_DEVICE_ID}")
+
+#
+# DTS compiler python dependencies
+#
+
+execute_process(
+    COMMAND python -m pip install lark==1.3.1 pyyaml==6.0.3
+    WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}"
+)
+
+#
+# Devicetree dependency collection
+#
+
+execute_process(
+    COMMAND python "${PROJECT_ROOT}/Buildscripts/DevicetreeCompiler/dependencies.py" "${DEVICETREE_LOCATION}"
+    WORKING_DIRECTORY "${PROJECT_ROOT}"
+    OUTPUT_VARIABLE DEVICE_DEPENDENCIES
+    OUTPUT_STRIP_TRAILING_WHITESPACE
+)
+# Tokenize to array of lines
+separate_arguments(DEVICE_DEPENDENCIES UNIX_COMMAND "${DEVICE_DEPENDENCIES}")
+
+#
+# "Generated/" directory creation
+#
 
 set(GENERATED_DIR "${CMAKE_CURRENT_BINARY_DIR}/Generated")
 # Ensure the directory is built in the correct CMake build phase
@@ -21,37 +51,53 @@ if (DEFINED CMAKE_CURRENT_BINARY_DIR)
     file(MAKE_DIRECTORY "${GENERATED_DIR}")
 endif ()
 
+#
+# Component
+#
+
+list(APPEND REQUIRES_LIST
+    Tactility
+    TactilityKernel
+)
+
+# Add devicetree dependencies
+foreach(dts_dependency IN LISTS DEVICE_DEPENDENCIES)
+    message("Adding DTS dependency ${dts_dependency}")
+    list(APPEND REQUIRES_LIST ${dts_dependency})
+endforeach()
+
 if (DEFINED ENV{ESP_IDF_VERSION})
+    list(APPEND REQUIRES_LIST
+        TactilityC
+    )
 
     idf_component_register(
         SRCS ${SOURCE_FILES} "${GENERATED_DIR}/devicetree.c"
-        REQUIRES Tactility TactilityC TactilityKernel platform-esp32 ${TACTILITY_DEVICE_PROJECT}
+        REQUIRES ${REQUIRES_LIST}
     )
-
 else ()
-
+    list(APPEND REQUIRES_LIST
-    add_executable(FirmwareSim ${SOURCE_FILES} "${GENERATED_DIR}/devicetree.c")
-    target_link_libraries(FirmwareSim PRIVATE
-        Tactility
         TactilityCore
         TactilityFreeRtos
-        TactilityKernel
         hal-device-module
         lvgl-module
-        Simulator
+        SDL2::SDL2-static
-        platform-posix
+        SDL2-static
-        SDL2::SDL2-static SDL2-static
     )
-
+    add_executable(FirmwareSim ${SOURCE_FILES} "${GENERATED_DIR}/devicetree.c")
+    target_link_libraries(FirmwareSim PRIVATE ${REQUIRES_LIST})
 endif ()
 
+#
+# Devicetree code generation
+#
+
 add_custom_target(AlwaysRun
     COMMAND ${CMAKE_COMMAND} -E rm -f "${GENERATED_DIR}/devicetree.c"
 )
 add_custom_command(
     OUTPUT "${GENERATED_DIR}/devicetree.c"
         "${GENERATED_DIR}/devicetree.h"
-    COMMAND pip install lark==1.3.1 pyyaml==6.0.3
     COMMAND python "${CMAKE_SOURCE_DIR}/Buildscripts/DevicetreeCompiler/compile.py"
         "${DEVICETREE_LOCATION}" "${GENERATED_DIR}"
     WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}"

Firmware/Source/Main.cpp

@@ -3,11 +3,6 @@
 #include <tactility/driver.h>
 #include <devicetree.h>
 
-// From the relevant platform
-extern struct Module platform_module;
-// From the relevant device
-extern struct Module device_module;
-
 #ifdef ESP_PLATFORM
 #include <tt_init.h>
 #else
@@ -32,7 +27,7 @@ void app_main() {
     tt_init_tactility_c(); // ELF bindings for side-loading on ESP32
 #endif
 
-    tt::run(config, &platform_module, &device_module, dts_devices);
+    tt::run(config, dts_modules, dts_devices);
 }
 
 } // extern

Platforms/platform-esp32/source/drivers/esp32_gpio.cpp

@@ -116,7 +116,7 @@ const static GpioControllerApi esp32_gpio_api  = {
     .get_native_pin_number = get_native_pin_number
 };
 
-extern struct Module platform_module;
+extern struct Module platform_esp32_module;
 
 Driver esp32_gpio_driver = {
     .name = "esp32_gpio",
@@ -125,7 +125,7 @@ Driver esp32_gpio_driver = {
     .stop_device = stop,
     .api =  (void*)&esp32_gpio_api,
     .device_type = &GPIO_CONTROLLER_TYPE,
-    .owner = &platform_module,
+    .owner = &platform_esp32_module,
     .internal = nullptr
 };
 

Platforms/platform-esp32/source/drivers/esp32_i2c.cpp

@@ -245,7 +245,7 @@ static constexpr I2cControllerApi ESP32_I2C_API = {
     .write_register = write_register
 };
 
-extern Module platform_module;
+extern Module platform_esp32_module;
 
 Driver esp32_i2c_driver = {
     .name = "esp32_i2c",
@@ -254,7 +254,7 @@ Driver esp32_i2c_driver = {
     .stop_device = stop,
     .api = &ESP32_I2C_API,
     .device_type = &I2C_CONTROLLER_TYPE,
-    .owner = &platform_module,
+    .owner = &platform_esp32_module,
     .internal = nullptr
 };
 

Platforms/platform-esp32/source/drivers/esp32_i2s.cpp

@@ -287,7 +287,7 @@ const static I2sControllerApi esp32_i2s_api = {
     .reset = reset
 };
 
-extern struct Module platform_module;
+extern struct Module platform_esp32_module;
 
 Driver esp32_i2s_driver = {
     .name = "esp32_i2s",
@@ -296,7 +296,7 @@ Driver esp32_i2s_driver = {
     .stop_device = stop,
     .api = (void*)&esp32_i2s_api,
     .device_type = &I2S_CONTROLLER_TYPE,
-    .owner = &platform_module,
+    .owner = &platform_esp32_module,
     .internal = nullptr
 };
 

Platforms/platform-esp32/source/drivers/esp32_spi.cpp

@@ -142,7 +142,7 @@ const static struct SpiControllerApi esp32_spi_api = {
     .unlock = unlock
 };
 
-extern struct Module platform_module;
+extern struct Module platform_esp32_module;
 
 Driver esp32_spi_driver = {
     .name = "esp32_spi",
@@ -151,7 +151,7 @@ Driver esp32_spi_driver = {
     .stop_device = stop,
     .api = (void*)&esp32_spi_api,
     .device_type = &SPI_CONTROLLER_TYPE,
-    .owner = &platform_module,
+    .owner = &platform_esp32_module,
     .internal = nullptr
 };
 

Platforms/platform-esp32/source/drivers/esp32_uart.cpp

@@ -402,7 +402,7 @@ const static UartControllerApi esp32_uart_api = {
     .flush_input = flush_input
 };
 
-extern struct Module platform_module;
+extern struct Module platform_esp32_module;
 
 Driver esp32_uart_driver = {
     .name = "esp32_uart",
@@ -411,7 +411,7 @@ Driver esp32_uart_driver = {
     .stop_device = stop,
     .api = (void*)&esp32_uart_api,
     .device_type = &UART_CONTROLLER_TYPE,
-    .owner = &platform_module,
+    .owner = &platform_esp32_module,
     .internal = nullptr
 };
 

Platforms/platform-esp32/source/module.cpp

@@ -32,8 +32,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-// The name must be exactly "platform_module"
+struct Module platform_esp32_module = {
-struct Module platform_module = {
     .name = "platform-esp32",
     .start = start,
     .stop = stop,

Platforms/platform-posix/source/module.cpp

@@ -13,8 +13,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-// The name must be exactly "platform_module"
+struct Module platform_posix_module = {
-struct Module platform_module = {
     .name = "platform-posix",
     .start = start,
     .stop = stop,

Tactility/Include/Tactility/Tactility.h

@@ -23,11 +23,10 @@ struct Configuration {
 
 /**
  * @brief Main entry point for Tactility.
- * @param platformModule Platform module to start (non-null).
+ * @param dtsModules List of modules from devicetree, null-terminated, non-null parameter
- * @param deviceModule Device module to start (non-null).
  * @param dtsDevices Array that is terminated with DTS_DEVICE_TERMINATOR
  */
-void run(const Configuration& config, Module* platformModule, Module* deviceModule, struct DtsDevice dtsDevices[]);
+void run(const Configuration& config, Module* dtsModules[], DtsDevice dtsDevices[]);
 
 /**
  * While technically nullable, this instance is always set if tt_init() succeeds.

Tactility/Source/Tactility.cpp

@@ -323,23 +323,19 @@ void registerApps() {
     registerInstalledAppsFromSdCards();
 }
 
-void run(const Configuration& config, Module* platformModule, Module* deviceModule, DtsDevice dtsDevices[]) {
+void run(const Configuration& config, Module* dtsModules[], DtsDevice dtsDevices[]) {
     LOGGER.info("Tactility v{} on {} ({})", TT_VERSION, CONFIG_TT_DEVICE_NAME, CONFIG_TT_DEVICE_ID);
 
     assert(config.hardware);
 
-    LOGGER.info(R"(Calling kernel_init with modules: "{}" and "{}")", platformModule->name, deviceModule->name);
+    LOGGER.info("Initializing kernel");
-    if (kernel_init(platformModule, deviceModule, dtsDevices) != ERROR_NONE) {
+    if (kernel_init(dtsModules, dtsDevices) != ERROR_NONE) {
         LOGGER.error("Failed to initialize kernel");
         return;
     }
 
     // hal-device-module
-    check(module_construct(&hal_device_module) == ERROR_NONE);
+    check(module_construct_add_start(&hal_device_module) == ERROR_NONE);
-    check(module_add(&hal_device_module) == ERROR_NONE);
-    check(module_start(&hal_device_module) == ERROR_NONE);
-
-    const hal::Configuration& hardware = *config.hardware;
 
     // Assign early so starting services can use it
     config_instance = &config;

TactilityKernel/bindings/i2c-device.yaml

@@ -1,6 +1,6 @@
 description: I2C device
 
 properties:
-  register:
+  reg:
     required: true
     description: device address on the bus

TactilityKernel/include/tactility/kernel_init.h

@@ -1,21 +1,20 @@
 #pragma once
 
+#include <tactility/dts.h>
+#include <tactility/error.h>
+#include <tactility/module.h>
+
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-#include <tactility/device.h>
-#include <tactility/error.h>
-#include <tactility/module.h>
-
 /**
- * Initialize the kernel with platform and device modules, and a device tree.
+ * Initialize the kernel with the provided modules from the device tree
- * @param platform_module The platform module to start. This module should not be constructed yet.
+ * @param dts_modules List of modules from devicetree, null-terminated. Non-null parameter.
- * @param device_module The device module to start. This module should not be constructed yet. This parameter can be NULL.
+ * @param dts_devices The list of generated devices from the devicetree. The array must be terminated with DTS_DEVICE_TERMINATOR. Non-null parameter.
- * @param dts_devices The list of generated devices from the devicetree. The array must be terminated with DTS_DEVICE_TERMINATOR. 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 DtsDevice dts_devices[]);
+error_t kernel_init(struct Module* dts_modules[], struct DtsDevice dts_devices[]);
 
 #ifdef __cplusplus
 }

TactilityKernel/include/tactility/module.h

@@ -3,6 +3,7 @@
 
 #include "error.h"
 #include <stdbool.h>
+#include <stddef.h>
 #include <stdint.h>
 
 #ifdef __cplusplus

TactilityKernel/source/kernel_init.cpp

@@ -1,5 +1,6 @@
-#include "tactility/dts.h"
 #include <tactility/kernel_init.h>
+
+#include <tactility/device.h>
 #include <tactility/log.h>
 
 #ifdef __cplusplus
@@ -8,7 +9,7 @@ extern "C" {
 
 #define TAG "kernel"
 
-extern const struct ModuleSymbol KERNEL_SYMBOLS[];
+extern const ModuleSymbol KERNEL_SYMBOLS[];
 
 static error_t start() {
     extern Driver root_driver;
@@ -20,7 +21,7 @@ static error_t stop() {
     return ERROR_NONE;
 }
 
-struct Module root_module = {
+Module root_module = {
     .name = "kernel",
     .start = start,
     .stop = stop,
@@ -28,7 +29,7 @@ struct Module root_module = {
     .internal = nullptr
 };
 
-error_t kernel_init(struct Module* platform_module, struct Module* device_module, struct DtsDevice dts_devices[]) {
+error_t kernel_init(Module* dts_modules[], DtsDevice dts_devices[]) {
     LOG_I(TAG, "init");
 
     if (module_construct_add_start(&root_module) != ERROR_NONE) {
@@ -36,19 +37,15 @@ error_t kernel_init(struct Module* platform_module, struct Module* device_module
         return ERROR_RESOURCE;
     }
 
-    if (module_construct_add_start(platform_module) != ERROR_NONE) {
+    Module** dts_module = dts_modules;
-        LOG_E(TAG, "platform module init failed");
+    while (*dts_module != nullptr) {
-        return ERROR_RESOURCE;
+        if (module_construct_add_start(*dts_module) != ERROR_NONE) {
-    }
+            LOG_E(TAG, "dts module init failed: %s", (*dts_module)->name);
-
-    if (device_module != nullptr) {
-        if (module_construct_add_start(device_module) != ERROR_NONE) {
-            LOG_E(TAG, "device module init failed");
             return ERROR_RESOURCE;
         }
+        dts_module++;
     }
 
-    if (dts_devices) {
     DtsDevice* dts_device = dts_devices;
     while (dts_device->device != nullptr) {
         if (dts_device->status == DTS_DEVICE_STATUS_OKAY) {
@@ -66,7 +63,6 @@ error_t kernel_init(struct Module* platform_module, struct Module* device_module
         }
         dts_device++;
     }
-    }
 
     LOG_I(TAG, "init done");
     return ERROR_NONE;

Tests/Tactility/Source/Main.cpp

@@ -5,8 +5,10 @@
 #include "FreeRTOS.h"
 #include "task.h"
 
-#include <tactility/kernel_init.h>
+#include <tactility/check.h>
+#include <tactility/dts.h>
 #include <tactility/hal_device_module.h>
+#include <tactility/kernel_init.h>
 
 typedef struct {
     int argc;
@@ -15,7 +17,7 @@ typedef struct {
 } TestTaskData;
 
 // From the relevant platform
-extern "C" struct Module platform_module;
+extern "C" struct Module platform_posix_module;
 
 void test_task(void* parameter) {
     auto* data = (TestTaskData*)parameter;
@@ -27,7 +29,9 @@ 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, &hal_device_module, nullptr) == ERROR_NONE);
+    Module* dts_modules[] = { &platform_posix_module, &hal_device_module, nullptr };
+    DtsDevice dts_devices[] = { DTS_DEVICE_TERMINATOR };
+    check(kernel_init(dts_modules, dts_devices) == ERROR_NONE);
 
     data->result = context.run();
 

Tests/TactilityKernel/Source/Main.cpp

@@ -1,7 +1,9 @@
 #define DOCTEST_CONFIG_IMPLEMENT
 #include "doctest.h"
 #include <cassert>
+#include <tactility/check.h>
 
+#include <tactility/dts.h>
 #include <tactility/freertos/task.h>
 #include <tactility/kernel_init.h>
 
@@ -11,10 +13,8 @@ typedef struct {
     int result;
 } TestTaskData;
 
-extern "C" {
 // From the relevant platform
-extern struct Module platform_module;
+extern "C" struct Module platform_posix_module;
-}
 
 void test_task(void* parameter) {
     auto* data = (TestTaskData*)parameter;
@@ -26,7 +26,9 @@ 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);
+    Module* dts_modules[] = { &platform_posix_module, nullptr };
+    DtsDevice dts_devices[] = { DTS_DEVICE_TERMINATOR };
+    check(kernel_init(dts_modules, dts_devices) == ERROR_NONE);
 
     data->result = context.run();