diff --git a/graphics/composer/aidl/aidl_api/android.hardware.graphics.composer3/current/android/hardware/graphics/composer3/ClientTarget.aidl b/graphics/composer/aidl/aidl_api/android.hardware.graphics.composer3/current/android/hardware/graphics/composer3/ClientTarget.aidl
index 7632707..06ed922 100644
--- a/graphics/composer/aidl/aidl_api/android.hardware.graphics.composer3/current/android/hardware/graphics/composer3/ClientTarget.aidl
+++ b/graphics/composer/aidl/aidl_api/android.hardware.graphics.composer3/current/android/hardware/graphics/composer3/ClientTarget.aidl
@@ -37,4 +37,5 @@
   android.hardware.graphics.composer3.Buffer buffer;
   android.hardware.graphics.common.Dataspace dataspace;
   android.hardware.graphics.common.Rect[] damage;
+  float hdrSdrRatio = 1.0f;
 }
diff --git a/graphics/composer/aidl/aidl_api/android.hardware.graphics.composer3/current/android/hardware/graphics/composer3/DisplayRequest.aidl b/graphics/composer/aidl/aidl_api/android.hardware.graphics.composer3/current/android/hardware/graphics/composer3/DisplayRequest.aidl
index 00598eb..e6db116 100644
--- a/graphics/composer/aidl/aidl_api/android.hardware.graphics.composer3/current/android/hardware/graphics/composer3/DisplayRequest.aidl
+++ b/graphics/composer/aidl/aidl_api/android.hardware.graphics.composer3/current/android/hardware/graphics/composer3/DisplayRequest.aidl
@@ -37,12 +37,12 @@
   long display;
   int mask;
   android.hardware.graphics.composer3.DisplayRequest.LayerRequest[] layerRequests;
-  const int FLIP_CLIENT_TARGET = (1 << 0);
-  const int WRITE_CLIENT_TARGET_TO_OUTPUT = (1 << 1);
+  const int FLIP_CLIENT_TARGET = (1 << 0) /* 1 */;
+  const int WRITE_CLIENT_TARGET_TO_OUTPUT = (1 << 1) /* 2 */;
   @VintfStability
   parcelable LayerRequest {
     long layer;
     int mask;
-    const int CLEAR_CLIENT_TARGET = (1 << 0);
+    const int CLEAR_CLIENT_TARGET = (1 << 0) /* 1 */;
   }
 }
diff --git a/graphics/composer/aidl/aidl_api/android.hardware.graphics.composer3/current/android/hardware/graphics/composer3/FormatColorComponent.aidl b/graphics/composer/aidl/aidl_api/android.hardware.graphics.composer3/current/android/hardware/graphics/composer3/FormatColorComponent.aidl
index 1990350..89dae83 100644
--- a/graphics/composer/aidl/aidl_api/android.hardware.graphics.composer3/current/android/hardware/graphics/composer3/FormatColorComponent.aidl
+++ b/graphics/composer/aidl/aidl_api/android.hardware.graphics.composer3/current/android/hardware/graphics/composer3/FormatColorComponent.aidl
@@ -34,8 +34,8 @@
 package android.hardware.graphics.composer3;
 @Backing(type="byte") @VintfStability
 enum FormatColorComponent {
-  FORMAT_COMPONENT_0 = (1 << 0),
-  FORMAT_COMPONENT_1 = (1 << 1),
-  FORMAT_COMPONENT_2 = (1 << 2),
-  FORMAT_COMPONENT_3 = (1 << 3),
+  FORMAT_COMPONENT_0 = (1 << 0) /* 1 */,
+  FORMAT_COMPONENT_1 = (1 << 1) /* 2 */,
+  FORMAT_COMPONENT_2 = (1 << 2) /* 4 */,
+  FORMAT_COMPONENT_3 = (1 << 3) /* 8 */,
 }
diff --git a/graphics/composer/aidl/android/hardware/graphics/composer3/ClientTarget.aidl b/graphics/composer/aidl/android/hardware/graphics/composer3/ClientTarget.aidl
index 56488d5..bc9f63a 100644
--- a/graphics/composer/aidl/android/hardware/graphics/composer3/ClientTarget.aidl
+++ b/graphics/composer/aidl/android/hardware/graphics/composer3/ClientTarget.aidl
@@ -36,4 +36,14 @@
      * The surface damage regions.
      */
     Rect[] damage;
+
+    /**
+     * The HDR/SDR ratio.
+     * Only meaningful for extended_range client targets to communicate the amount of HDR heaedroom
+     * inside the client target. For floating point client targets, this means that for each color
+     * channel the maximum SDR luminance is 1.0, and the maximum display relative luminance is
+     * the hdrSdrRatio.
+     * Note that this ratio is meant to be >= 1.0.
+     */
+    float hdrSdrRatio = 1.0f;
 }
diff --git a/graphics/composer/aidl/include/android/hardware/graphics/composer3/ComposerClientWriter.h b/graphics/composer/aidl/include/android/hardware/graphics/composer3/ComposerClientWriter.h
index 92ed6d3..c7bd5e0 100644
--- a/graphics/composer/aidl/include/android/hardware/graphics/composer3/ComposerClientWriter.h
+++ b/graphics/composer/aidl/include/android/hardware/graphics/composer3/ComposerClientWriter.h
@@ -83,11 +83,13 @@
     }
 
     void setClientTarget(int64_t display, uint32_t slot, const native_handle_t* target,
-                         int acquireFence, Dataspace dataspace, const std::vector<Rect>& damage) {
+                         int acquireFence, Dataspace dataspace, const std::vector<Rect>& damage,
+                         float hdrSdrRatio) {
         ClientTarget clientTargetCommand;
         clientTargetCommand.buffer = getBufferCommand(slot, target, acquireFence);
         clientTargetCommand.dataspace = dataspace;
         clientTargetCommand.damage.assign(damage.begin(), damage.end());
+        clientTargetCommand.hdrSdrRatio = hdrSdrRatio;
         getDisplayCommand(display).clientTarget.emplace(std::move(clientTargetCommand));
     }
 
diff --git a/graphics/composer/aidl/vts/VtsHalGraphicsComposer3_ReadbackTest.cpp b/graphics/composer/aidl/vts/VtsHalGraphicsComposer3_ReadbackTest.cpp
index 58eca6e..2e3f4df 100644
--- a/graphics/composer/aidl/vts/VtsHalGraphicsComposer3_ReadbackTest.cpp
+++ b/graphics/composer/aidl/vts/VtsHalGraphicsComposer3_ReadbackTest.cpp
@@ -500,7 +500,7 @@
             const auto unlockStatus = graphicBuffer->unlockAsync(&clientFence);
             ASSERT_EQ(::android::OK, unlockStatus);
             mWriter->setClientTarget(getPrimaryDisplayId(), /*slot*/ 0, buffer, clientFence,
-                                     clientDataspace, std::vector<common::Rect>(1, damage));
+                                     clientDataspace, std::vector<common::Rect>(1, damage), 1.f);
             layer->setToClientComposition(*mWriter);
             mWriter->validateDisplay(getPrimaryDisplayId(), ComposerClientWriter::kNoTimestamp,
                                      VtsComposerClient::kNoFrameIntervalNs);
@@ -608,7 +608,7 @@
         const auto unlockStatus = graphicBuffer->unlockAsync(&clientFence);
         ASSERT_EQ(::android::OK, unlockStatus);
         mWriter->setClientTarget(getPrimaryDisplayId(), /*slot*/ 0, buffer, clientFence,
-                                 clientDataspace, std::vector<common::Rect>(1, clientFrame));
+                                 clientDataspace, std::vector<common::Rect>(1, clientFrame), 1.f);
         clientLayer->setToClientComposition(*mWriter);
         mWriter->validateDisplay(getPrimaryDisplayId(), ComposerClientWriter::kNoTimestamp,
                                  VtsComposerClient::kNoFrameIntervalNs);
diff --git a/graphics/composer/aidl/vts/VtsHalGraphicsComposer3_TargetTest.cpp b/graphics/composer/aidl/vts/VtsHalGraphicsComposer3_TargetTest.cpp
index c135298..ca1b6d8 100644
--- a/graphics/composer/aidl/vts/VtsHalGraphicsComposer3_TargetTest.cpp
+++ b/graphics/composer/aidl/vts/VtsHalGraphicsComposer3_TargetTest.cpp
@@ -1828,7 +1828,7 @@
 
     auto& writer = getWriter(getPrimaryDisplayId());
     writer.setClientTarget(getPrimaryDisplayId(), /*slot*/ 0, nullptr, /*acquireFence*/ -1,
-                           Dataspace::UNKNOWN, std::vector<Rect>());
+                           Dataspace::UNKNOWN, std::vector<Rect>(), 1.0f);
 
     execute();
 }