Merge "Add HAL entry to allow querying device impl version."

neuralnetworks/1.2/IDevice.hal

@@ -25,6 +25,36 @@ import @1.1::IDevice;
  * This interface represents a device driver.
  */
 interface IDevice extends @1.1::IDevice {
+    /**
+     * Get the version string of the driver implementation.
+     *
+     * The version string must be a unique token among the set of version strings of
+     * drivers of a specific device. The token identifies the device driver's
+     * implementation. The token must not be confused with the feature level which is solely
+     * defined by the interface version. This API is opaque to the Android framework, but the
+     * Android framework may use the information for debugging or to pass on to NNAPI applications.
+     *
+     * Application developers sometimes have specific requirements to ensure good user experiences,
+     * and they need more information to make intelligent decisions when the Android framework cannot.
+     * For example, combined with the device name and other information, the token can help
+     * NNAPI applications filter devices based on their needs:
+     *     - An application demands a certain level of performance, but a specific version of
+     *       the driver cannot meet that requirement because of a performance regression.
+     *       The application can blacklist the driver based on the version provided.
+     *     - An application has a minimum precision requirement, but certain versions of
+     *       the driver cannot meet that requirement because of bugs or certain optimizations.
+     *       The application can filter out versions of these drivers.
+     *
+     * @return status Error status returned from querying the version string. Must be:
+     *     - NONE if the query was successful
+     *     - DEVICE_UNAVAILABLE if driver is offline or busy
+     *     - GENERAL_FAILURE if the query resulted in an
+     *       unspecified error
+     * @return version The version string of the device implementation.
+     *     Must have nonzero length
+     */
+    getVersionString() generates (ErrorStatus status, string version);
+
     /**
      * Gets the supported operations in a model.
      *

neuralnetworks/1.2/vts/functional/BasicTests.cpp

@@ -37,6 +37,14 @@ TEST_F(NeuralnetworksHidlTest, StatusTest) {
     EXPECT_EQ(DeviceStatus::AVAILABLE, static_cast<DeviceStatus>(status));
 }
 
+// device version test
+TEST_F(NeuralnetworksHidlTest, GetDeviceVersionStringTest) {
+    Return<void> ret = device->getVersionString([](ErrorStatus status, const hidl_string& version) {
+        EXPECT_EQ(ErrorStatus::NONE, status);
+        EXPECT_LT(0, version.size());
+    });
+    EXPECT_TRUE(ret.isOk());
+}
 }  // namespace functional
 }  // namespace vts
 }  // namespace V1_2