1 files changed, 114 insertions, 0 deletions
diff --git a/usb/usb/UsbDataSessionMonitor.h b/usb/usb/UsbDataSessionMonitor.h
new file mode 100644
index 0000000..596f378
--- /dev/null
+++ b/usb/usb/UsbDataSessionMonitor.h
@@ -0,0 +1,114 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * 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.
+ */
+
+#pragma once
+
+#include <aidl/android/hardware/usb/ComplianceWarning.h>
+#include <aidl/android/hardware/usb/PortDataRole.h>
+#include <android-base/chrono_utils.h>
+#include <android-base/unique_fd.h>
+
+#include <set>
+#include <string>
+#include <vector>
+
+namespace aidl {
+namespace android {
+namespace hardware {
+namespace usb {
+
+using ::aidl::android::hardware::usb::ComplianceWarning;
+using ::aidl::android::hardware::usb::PortDataRole;
+using ::android::base::boot_clock;
+using ::android::base::unique_fd;
+
+/*
+ * UsbDataSessionMonitor monitors the usb device state sysfs of 3 different usb devices
+ * including device mode (udc), host mode high-speed port and host mode super-speed port. It
+ * reports Suez metrics for each data session and also provides API to query the compliance
+ * warnings detected in the current usb data session.
+ */
+class UsbDataSessionMonitor {
+  public:
+    /*
+     * The host mode high-speed port and super-speed port can be assigned to either host1 or
+     * host2 without affecting functionality.
+     *
+     * UeventRegex: name regex of the device that's being monitored. The regex is matched against
+     *              uevent to detect dynamic creation/deletion/change of the device.
+     * StatePath: usb device state sysfs path of the device, monitored by epoll.
+     * dataRolePath: path to the usb data role sysfs, monitored by epoll.
+     * updatePortStatusCb: the callback is invoked when the compliance warings changes.
+     */
+    UsbDataSessionMonitor(const std::string &deviceUeventRegex, const std::string &deviceStatePath,
+                          const std::string &host1UeventRegex, const std::string &host1StatePath,
+                          const std::string &host2UeventRegex, const std::string &host2StatePath,
+                          const std::string &dataRolePath,
+                          std::function<void()> updatePortStatusCb);
+    ~UsbDataSessionMonitor();
+    // Returns the compliance warnings detected in the current data session.
+    void getComplianceWarnings(const PortDataRole &role, std::vector<ComplianceWarning> *warnings);
+
+  private:
+    struct usbDeviceState {
+        unique_fd fd;
+        std::string filePath;
+        std::string ueventRegex;
+        // Usb device states reported by state sysfs
+        std::vector<std::string> states;
+        // Timestamps of when the usb device states were captured
+        std::vector<boot_clock::time_point> timestamps;
+    };
+
+    static void *monitorThread(void *param);
+    void handleUevent();
+    void handleDataRoleEvent();
+    void handleDeviceStateEvent(struct usbDeviceState *deviceState);
+    void clearDeviceStateEvents(struct usbDeviceState *deviceState);
+    void reportUsbDataSessionMetrics();
+    void evaluateComplianceWarning();
+    void notifyComplianceWarning();
+    void updateUdcBindStatus(const std::string &devname);
+
+    pthread_t mMonitor;
+    unique_fd mEpollFd;
+    unique_fd mUeventFd;
+    unique_fd mDataRoleFd;
+    struct usbDeviceState mDeviceState;
+    struct usbDeviceState mHost1State;
+    struct usbDeviceState mHost2State;
+    std::set<ComplianceWarning> mWarningSet;
+    // Callback function to notify the caller when there's a change in compliance warnings.
+    std::function<void()> mUpdatePortStatusCb;
+    /*
+     * Cache relevant info for a USB data session when one starts, including
+     * the data role and the time when the session starts.
+     */
+    PortDataRole mDataRole;
+    boot_clock::time_point mDataSessionStart;
+    /*
+     * In gadget mode: this indicates whether the udc device is bound to the configfs driver, which
+     * is done by userspace writing the udc device name to /config/usb_gadget/g1/UDC. When unbound,
+     * the gadget is in soft pulldown state and is expected not to enumerate. During gadget
+     * function switch, the udc device usually go through unbind and bind.
+     */
+    bool mUdcBind;
+};
+
+}  // namespace usb
+}  // namespace hardware
+}  // namespace android
+}  // namespace aidl