Fixes for grove and i2c changes (#31)

Apps/M5UnitTest/main/Source/GroveLookup.cpp

@@ -0,0 +1,45 @@
+#include "GroveLookup.h"
+#include <tactility/drivers/i2c_controller.h>
+#include <tactility/drivers/uart_controller.h>
+
+namespace {
+
+struct GroveChildSearch {
+    const DeviceType* childType;
+    Device* result;
+};
+
+bool onGroveDevice(Device* groveDevice, void* context) {
+    auto* search = static_cast<GroveChildSearch*>(context);
+
+    GroveMode mode;
+    if (grove_get_mode(groveDevice, &mode) != ERROR_NONE) return true;
+    if (mode != (search->childType == &I2C_CONTROLLER_TYPE ? GROVE_MODE_I2C : GROVE_MODE_UART)) return true;
+
+    device_for_each_child(groveDevice, search, [](Device* child, void* ctx) -> bool {
+        auto* s = static_cast<GroveChildSearch*>(ctx);
+        if (device_get_type(child) == s->childType && device_is_ready(child)) {
+            s->result = child;
+            return false; // stop - found it
+        }
+        return true;
+    });
+
+    return search->result == nullptr; // stop outer iteration once found
+}
+
+Device* findGroveChild(const DeviceType* childType) {
+    GroveChildSearch search{childType, nullptr};
+    device_for_each_of_type(&GROVE_TYPE, &search, onGroveDevice);
+    return search.result;
+}
+
+} // namespace
+
+Device* findGroveI2cDevice() {
+    return findGroveChild(&I2C_CONTROLLER_TYPE);
+}
+
+Device* findGroveUartDevice() {
+    return findGroveChild(&UART_CONTROLLER_TYPE);
+}