diff --git a/current.txt b/current.txt
index 5dba85b..37de397 100644
--- a/current.txt
+++ b/current.txt
@@ -395,8 +395,9 @@
 1fb32361286b938d48a55c2539c846732afce0b99fe08590f556643125bc13d3 android.hardware.neuralnetworks@1.0::types
 e22e8135d061d0e9c4c1a70c25c19fdba10f4d3cda9795ef25b6392fc520317c android.hardware.neuralnetworks@1.1::types
 1d4a5776614c08b5d794a5ec5ab04697260cbd4b3441d5935cd53ee71d19da02 android.hardware.radio@1.0::IRadioResponse
-271187e261b30c01a33011aea257c07a2d2f05b72943ebee89e973e997849973 android.hardware.radio@1.0::types
+ed9da80ec0c96991fd03f0a46107815d0e50f764656e49dba4980fa5c31d5bc3 android.hardware.radio@1.0::types
 1d19720d4fd38b1095f0f555a4bd92b3b12c9b1d0f560b0e9a474cd6dcc20db6 android.hardware.radio@1.2::IRadio
+cd1757867a5e3a3faa362e785239515870d1a3c9ce756c6f0cf0f0fd8aac2547 android.hardware.radio@1.2::types
 e78cf871f9fd1c072874e481e06e18e2681763cf2aa38c1fd777d53bab4eb69b android.hardware.sensors@1.0::types
 1722ad002317b1fae1400de709e90f442d94ef22864e05f7a12af48c32e8edc8 android.hardware.usb@1.1::types
 29c8da7a13c40d488f569c812441d5754ee45bdcdb8ce6564f524b708d10a057 android.hardware.vibrator@1.1::types
diff --git a/radio/1.0/types.hal b/radio/1.0/types.hal
index 17718e0..8393cf5 100644
--- a/radio/1.0/types.hal
+++ b/radio/1.0/types.hal
@@ -1230,85 +1230,108 @@
 
 struct GsmSignalStrength {
     uint32_t signalStrength;              // Valid values are (0-61, 99) as defined in
-                                          // TS 27.007 8.69
-    uint32_t bitErrorRate;                // bit error rate (0-7, 99) as defined in TS 27.007 8.5
+                                          // TS 27.007 8.69; INT_MAX means invalid/unreported.
+    uint32_t bitErrorRate;                // bit error rate (0-7, 99) as defined in TS 27.007 8.5;
+                                          // INT_MAX means invalid/unreported.
     int32_t timingAdvance;                // Timing Advance in bit periods. 1 bit period = 48/13 us.
-                                          // INT_MAX denotes invalid value
+                                          // INT_MAX means invalid/unreported.
 };
 
 struct WcdmaSignalStrength{
     int32_t signalStrength;               // Valid values are (0-31, 99) as defined in
-                                          // TS 27.007 8.5
-    int32_t bitErrorRate;                 // bit error rate (0-7, 99) as defined in TS 27.007 8.5
+                                          // TS 27.007 8.5; INT_MAX means unreported.
+    int32_t bitErrorRate;                 // bit error rate (0-7, 99) as defined in TS 27.007 8.5;
+                                          // INT_MAX means invalid/unreported.
 };
 
 struct CdmaSignalStrength {
     uint32_t dbm;                         // This value is the actual RSSI
                                           // value multiplied by -1. Example: If the
                                           // actual RSSI is -75, then this response value will
-                                          // be 75.
+                                          // be 75. INT_MAX means invalid/unreported.
     uint32_t ecio;                        // This value is the actual
                                           // Ec/Io multiplied by -10. Example: If the
                                           // actual Ec/Io is -12.5 dB, then this response value
-                                          // will be 125.
+                                          // will be 125. INT_MAX means invalid/unreported.
 };
 
 struct EvdoSignalStrength {
     uint32_t dbm;                         // This value is the actual
                                           // RSSI value multiplied by -1.
                                           // Example: If the actual RSSI is -75,
-                                          // then this response value will be 75.
+                                          // then this response value will be 75; INT_MAX means
+                                          // invalid/unreported.
     uint32_t ecio;                        // This value is the actual
                                           // Ec/Io multiplied by -10. Example: If the
                                           // actual Ec/Io is -12.5 dB, then this response value
-                                          // will be 125.
+                                          // will be 125; INT_MAX means invalid/unreported.
     uint32_t signalNoiseRatio;            // Valid values are 0-8. 8 is the highest signal to
-                                          // noise ratio.
+                                          // noise ratio; INT_MAX means invalid/unreported.
 };
 
 struct LteSignalStrength {
     uint32_t signalStrength;              // Valid values are (0-31, 99) as defined in
-                                          // TS 27.007 8.5
+                                          // TS 27.007 8.5; INT_MAX means invalid/unreported.
     uint32_t rsrp;                        // The current Reference Signal Receive Power in dBm
                                           // multipled by -1.
-                                          // Range: 44 to 140 dBm
-                                          // INT_MAX: 0x7FFFFFFF denotes invalid value.
+                                          // Range: 44 to 140 dBm;
+                                          // INT_MAX: 0x7FFFFFFF denotes invalid/unreported value.
                                           // Reference: 3GPP TS 36.133 9.1.4
     uint32_t rsrq;                        // The current Reference Signal Receive Quality in dB
                                           // multiplied by -1.
-                                          // Range: 20 to 3 dB.
-                                          // INT_MAX: 0x7FFFFFFF denotes invalid value.
+                                          // Range: 20 to 3 dB;
+                                          // INT_MAX: 0x7FFFFFFF denotes invalid/unreported value.
                                           // Reference: 3GPP TS 36.133 9.1.7
     int32_t rssnr;                        // The current reference signal signal-to-noise ratio in
                                           // 0.1 dB units.
                                           // Range: -200 to +300 (-200 = -20.0 dB, +300 = 30dB).
-                                          // INT_MAX : 0x7FFFFFFF denotes invalid value.
+                                          // INT_MAX: 0x7FFFFFFF denotes invalid/unreported value.
                                           // Reference: 3GPP TS 36.101 8.1.1
     uint32_t cqi;                         // The current Channel Quality Indicator.
                                           // Range: 0 to 15.
-                                          // INT_MAX : 0x7FFFFFFF denotes invalid value.
+                                          // INT_MAX: 0x7FFFFFFF denotes invalid/unreported value.
                                           // Reference: 3GPP TS 36.101 9.2, 9.3, A.4
     uint32_t timingAdvance;               // timing advance in micro seconds for a one way trip
                                           // from cell to device.
                                           // Approximate distance is calculated using
                                           // 300m/us * timingAdvance.
                                           // Range: 0 to 1282 inclusive.
-                                          // INT_MAX : 0x7FFFFFFF denotes unknown value.
+                                          // INT_MAX: 0x7FFFFFFF denotes invalid/unreported value.
                                           // Reference: 3GPP 36.213 section 4.2.3
 };
 
 struct TdScdmaSignalStrength {
     uint32_t rscp;                        // The Received Signal Code Power in dBm multiplied by -1.
                                           // Range : 25 to 120
-                                          // INT_MAX: 0x7FFFFFFF denotes invalid value.
+                                          // INT_MAX: 0x7FFFFFFF denotes invalid/unreported value.
                                           // Reference: 3GPP TS 25.123, section 9.1.1.1
 };
 
 struct SignalStrength {
+    /**
+     * If GSM measurements are provided, this structure must contain valid measurements; otherwise
+     * all fields should be set to INT_MAX to mark them as invalid.
+     */
     GsmSignalStrength gw;
+    /**
+     * If CDMA measurements are provided, this structure must contain valid measurements; otherwise
+     * all fields should be set to INT_MAX to mark them as invalid.
+     */
     CdmaSignalStrength cdma;
+    /**
+     * If EvDO measurements are provided, this structure must contain valid measurements; otherwise
+     * all fields should be set to INT_MAX to mark them as invalid.
+     */
     EvdoSignalStrength evdo;
+    /**
+     * If LTE measurements are provided, this structure must contain valid measurements; otherwise
+     * all fields should be set to INT_MAX to mark them as invalid.
+     */
     LteSignalStrength lte;
+    /**
+     * If TD-SCDMA measurements are provided, this structure must contain valid measurements;
+     * otherwise all fields should be set to INT_MAX to mark them as invalid.
+     */
     TdScdmaSignalStrength tdScdma;
 };
 
diff --git a/radio/1.2/types.hal b/radio/1.2/types.hal
index 4715fac..2dceeb1 100644
--- a/radio/1.2/types.hal
+++ b/radio/1.2/types.hal
@@ -427,11 +427,13 @@
     /**
      * CPICH RSCP as defined in TS 25.215 5.1.1
      * Valid values are (0-96, 255) as defined in TS 27.007 8.69
+     * INT_MAX denotes that the value is invalid/unreported.
      */
     uint32_t rscp;
     /**
      * Ec/No value as defined in TS 25.215 5.1.5
      * Valid values are (0-49, 255) as defined in TS 27.007 8.69
+     * INT_MAX denotes that the value is invalid/unreported.
      */
     uint32_t ecno;
 
@@ -441,26 +443,53 @@
     /**
      * UTRA carrier RSSI as defined in TS 25.225 5.1.4
      * Valid values are (0-31, 99) as defined in TS 27.007 8.5
+     * INT_MAX denotes that the value is invalid/unreported.
      */
     uint32_t signalStrength;
     /**
      * Transport Channel BER as defined in TS 25.225 5.2.5
      * Valid values are (0-7, 99) as defined in TS 27.007 8.5
+     * INT_MAX denotes that the value is invalid/unreported.
      */
     uint32_t bitErrorRate;
     /**
      * P-CCPCH RSCP as defined in TS 25.225 5.1.1
      * Valid values are (0-96, 255) as defined in TS 27.007 8.69
+     * INT_MAX denotes that the value is invalid/unreported.
      */
     uint32_t rscp;
 };
 
 struct SignalStrength {
+    /**
+     * If GSM measurements are provided, this structure must contain valid measurements; otherwise
+     * all fields should be set to INT_MAX to mark them as invalid.
+     */
     GsmSignalStrength gsm;
+    /**
+     * If CDMA measurements are provided, this structure must contain valid measurements; otherwise
+     * all fields should be set to INT_MAX to mark them as invalid.
+     */
     CdmaSignalStrength cdma;
+    /**
+     * If EvDO measurements are provided, this structure must contain valid measurements; otherwise
+     * all fields should be set to INT_MAX to mark them as invalid.
+     */
     EvdoSignalStrength evdo;
+    /**
+     * If LTE measurements are provided, this structure must contain valid measurements; otherwise
+     * all fields should be set to INT_MAX to mark them as invalid.
+     */
     LteSignalStrength lte;
+    /**
+     * If TD-SCDMA measurements are provided, this structure must contain valid measurements;
+     * otherwise all fields should be set to INT_MAX to mark them as invalid.
+     */
     TdScdmaSignalStrength tdScdma;
+    /**
+     * If WCDMA measurements are provided, this structure must contain valid measurements; otherwise
+     * all fields should be set to INT_MAX to mark them as invalid.
+     */
     WcdmaSignalStrength wcdma;
 };