diff --git a/packages/SettingsLib/Android.bp b/packages/SettingsLib/Android.bp
index 7560c41..3e58e9a 100644
--- a/packages/SettingsLib/Android.bp
+++ b/packages/SettingsLib/Android.bp
@@ -74,6 +74,7 @@
         "SettingsLibTwoTargetPreference",
         "SettingsLibSettingsTransition",
         "SettingsLibActivityEmbedding",
+        "zxing-core-1.7",
     ],
 }
 
diff --git a/packages/SettingsLib/src/com/android/settingslib/qrcode/QrCodeGenerator.java b/packages/SettingsLib/src/com/android/settingslib/qrcode/QrCodeGenerator.java
new file mode 100644
index 0000000..bc5824a
--- /dev/null
+++ b/packages/SettingsLib/src/com/android/settingslib/qrcode/QrCodeGenerator.java
@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2022 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.
+ */
+
+package com.android.settingslib.qrcode;
+
+import android.graphics.Bitmap;
+import android.graphics.Color;
+
+import com.google.zxing.BarcodeFormat;
+import com.google.zxing.EncodeHintType;
+import com.google.zxing.MultiFormatWriter;
+import com.google.zxing.WriterException;
+import com.google.zxing.common.BitMatrix;
+
+import java.nio.charset.CharsetEncoder;
+import java.nio.charset.StandardCharsets;
+import java.util.HashMap;
+import java.util.Map;
+
+public final class QrCodeGenerator {
+    /**
+     * Generates a barcode image with {@code contents}.
+     *
+     * @param contents The contents to encode in the barcode
+     * @param size     The preferred image size in pixels
+     * @return Barcode bitmap
+     */
+    public static Bitmap encodeQrCode(String contents, int size)
+            throws WriterException, IllegalArgumentException {
+        final Map<EncodeHintType, Object> hints = new HashMap<>();
+        if (!isIso88591(contents)) {
+            hints.put(EncodeHintType.CHARACTER_SET, StandardCharsets.UTF_8.name());
+        }
+
+        final BitMatrix qrBits = new MultiFormatWriter().encode(contents, BarcodeFormat.QR_CODE,
+                size, size, hints);
+        final Bitmap bitmap = Bitmap.createBitmap(size, size, Bitmap.Config.RGB_565);
+        for (int x = 0; x < size; x++) {
+            for (int y = 0; y < size; y++) {
+                bitmap.setPixel(x, y, qrBits.get(x, y) ? Color.BLACK : Color.WHITE);
+            }
+        }
+        return bitmap;
+    }
+
+    private static boolean isIso88591(String contents) {
+        CharsetEncoder encoder = StandardCharsets.ISO_8859_1.newEncoder();
+        return encoder.canEncode(contents);
+    }
+}
diff --git a/services/core/java/com/android/server/TelephonyRegistry.java b/services/core/java/com/android/server/TelephonyRegistry.java
index 2bb3952..724d17b 100644
--- a/services/core/java/com/android/server/TelephonyRegistry.java
+++ b/services/core/java/com/android/server/TelephonyRegistry.java
@@ -2808,6 +2808,11 @@
             throw new IllegalArgumentException("Invalid slot index: " + phoneId);
         }
 
+        // In case this is triggered from the caller who has handled multiple SIM config change
+        // firstly, we need to update the status (mNumPhone and mCarrierPrivilegeStates) firstly.
+        // This is almost a no-op if there is no multiple SIM config change in advance.
+        onMultiSimConfigChanged();
+
         synchronized (mRecords) {
             Record r = add(
                     callback.asBinder(), Binder.getCallingUid(), Binder.getCallingPid(), false);
@@ -2868,6 +2873,12 @@
                             + ", <packages=" + pii(privilegedPackageNames)
                             + ", uids=" + Arrays.toString(privilegedUids) + ">");
         }
+
+        // In case this is triggered from the caller who has handled multiple SIM config change
+        // firstly, we need to update the status (mNumPhone and mCarrierPrivilegeStates) firstly.
+        // This is almost a no-op if there is no multiple SIM config change in advance.
+        onMultiSimConfigChanged();
+
         synchronized (mRecords) {
             mCarrierPrivilegeStates.set(
                     phoneId, new Pair<>(privilegedPackageNames, privilegedUids));
@@ -2900,6 +2911,11 @@
                     + ", package=" + pii(packageName) + ", uid=" + uid);
         }
 
+        // In case this is triggered from the caller who has handled multiple SIM config change
+        // firstly, we need to update the status (mNumPhone and mCarrierServiceStates) firstly.
+        // This is almost a no-op if there is no multiple SIM config change in advance.
+        onMultiSimConfigChanged();
+
         synchronized (mRecords) {
             mCarrierServiceStates.set(
                     phoneId, new Pair<>(packageName, uid));
@@ -3364,7 +3380,8 @@
     }
 
     private boolean validatePhoneId(int phoneId) {
-        boolean valid = (phoneId >= 0) && (phoneId < mNumPhones);
+        // Call getActiveModemCount to get the latest value instead of depending on mNumPhone
+        boolean valid = (phoneId >= 0) && (phoneId < getTelephonyManager().getActiveModemCount());
         if (VDBG) log("validatePhoneId: " + valid);
         return valid;
     }