hdmi: connection: add rpi specific aidl hal

* Needed for AIDL HDMI-CEC HAL to work. Some functions that were in the
  HIDL HDMI-CEC HAL have been moved to separate HDMI connection HAL in the
  AIDL versions. Only returns connection status of HDMI ports on Pi.
  onHotplugEvent is not implemented.
* Use hardware/interfaces/tv/hdmi/connection/aidl/ as reference.

hdmi/connection/HdmiConnection.cpp

@@ -0,0 +1,119 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ * Copyright (C) 2025 KonstaKANG
+ *
+ * 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.
+ */
+
+#define LOG_TAG "android.hardware.tv.hdmi.connection-service.rpi"
+
+#include "HdmiConnection.h"
+
+#include <android-base/file.h>
+#include <android-base/logging.h>
+
+using android::base::ReadFileToString;
+using ndk::ScopedAStatus;
+using std::string;
+
+namespace android {
+namespace hardware {
+namespace tv {
+namespace hdmi {
+namespace connection {
+namespace implementation {
+
+static const string drmCard = "card0";
+
+HdmiConnection::HdmiConnection() {
+    mCallback = nullptr;
+
+    for (int i = 0; i < 2; i++) {
+        mPortInfos.push_back(
+                {.type = HdmiPortType::OUTPUT,
+                 .portId = i,
+                 .cecSupported = true,
+                 .arcSupported = false,
+                 .eArcSupported = false,
+                 .physicalAddress = 0xFFFF});
+        mHpdSignal.push_back(HpdSignal::HDMI_HPD_PHYSICAL);
+    }
+}
+
+HdmiConnection::~HdmiConnection() {
+    if (mCallback != nullptr) {
+        mCallback = nullptr;
+    }
+}
+
+ScopedAStatus HdmiConnection::getPortInfo(std::vector<HdmiPortInfo>* _aidl_return) {
+    *_aidl_return = mPortInfos;
+    return ScopedAStatus::ok();
+}
+
+ScopedAStatus HdmiConnection::isConnected(int32_t portId, bool* _aidl_return) {
+    if (portId != 0 && portId != 1) {
+        *_aidl_return = false;
+        return ScopedAStatus::ok();
+    }
+
+    bool connected = false;
+    string hdmiStatusPath = "/sys/class/drm/" + drmCard + "-HDMI-A-" + to_string(portId + 1) + "/status";
+    if (!access(hdmiStatusPath.c_str(), R_OK)) {
+        string connectedValue;
+        if (ReadFileToString(hdmiStatusPath, &connectedValue)) {
+            connected = !connectedValue.compare("connected\n");
+        }
+    }
+    LOG(INFO) << "portId: " << portId << ", connected: " << connected;
+
+    *_aidl_return = connected;
+    return ScopedAStatus::ok();
+}
+
+ScopedAStatus HdmiConnection::setCallback(const std::shared_ptr<IHdmiConnectionCallback>& callback) {
+    if (mCallback != nullptr) {
+        mCallback = nullptr;
+    }
+
+    if (callback != nullptr) {
+        mCallback = callback;
+    }
+
+    return ScopedAStatus::ok();
+}
+
+ScopedAStatus HdmiConnection::setHpdSignal(HpdSignal signal, int32_t portId) {
+    if (portId != 0 && portId != 1) {
+        return ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
+    }
+
+    mHpdSignal.at(portId) = signal;
+    return ScopedAStatus::ok();
+}
+
+ScopedAStatus HdmiConnection::getHpdSignal(int32_t portId, HpdSignal* _aidl_return) {
+    if (portId != 0 && portId != 1) {
+        return ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
+    }
+
+    *_aidl_return = mHpdSignal.at(portId);
+    return ScopedAStatus::ok();
+}
+
+}  // namespace implementation
+}  // namespace connection
+}  // namespace hdmi
+}  // namespace tv
+}  // namespace hardware
+}  // namespace android