diff --git a/modules/usbcamera/Camera.cpp b/modules/usbcamera/Camera.cpp
index cf62f7f..b396291 100644
--- a/modules/usbcamera/Camera.cpp
+++ b/modules/usbcamera/Camera.cpp
@@ -484,9 +484,9 @@
     // TODO: dump all settings
     dprintf(fd, "Most Recent Settings: (%p)\n", mSettings);
 
-    dprintf(fd, "Number of streams: %d\n", mStreams.size());
+    dprintf(fd, "Number of streams: %zu\n", mStreams.size());
     for (size_t i = 0; i < mStreams.size(); i++) {
-        dprintf(fd, "Stream %d/%d:\n", i, mStreams.size());
+        dprintf(fd, "Stream %zu/%zu:\n", i, mStreams.size());
         mStreams[i]->dump(fd);
     }
 }
diff --git a/modules/usbcamera/CameraHAL.cpp b/modules/usbcamera/CameraHAL.cpp
index 652e937..c54283b 100644
--- a/modules/usbcamera/CameraHAL.cpp
+++ b/modules/usbcamera/CameraHAL.cpp
@@ -65,7 +65,7 @@
 
 int CameraHAL::getNumberOfCameras() {
     android::Mutex::Autolock al(mModuleLock);
-    ALOGV("%s: %d", __func__, mCameras.size());
+    ALOGV("%s: %zu", __func__, mCameras.size());
     return static_cast<int>(mCameras.size());
 }
 
@@ -126,29 +126,29 @@
 }
 
 static hw_module_methods_t gCameraModuleMethods = {
-    open : open_dev
+    .open = open_dev
 };
 
 camera_module_t HAL_MODULE_INFO_SYM __attribute__ ((visibility("default"))) = {
-    common : {
-        tag                : HARDWARE_MODULE_TAG,
-        module_api_version : CAMERA_MODULE_API_VERSION_2_4,
-        hal_api_version    : HARDWARE_HAL_API_VERSION,
-        id                 : CAMERA_HARDWARE_MODULE_ID,
-        name               : "Default USB Camera HAL",
-        author             : "The Android Open Source Project",
-        methods            : &gCameraModuleMethods,
-        dso                : NULL,
-        reserved           : {0},
+    .common = {
+        .tag                = HARDWARE_MODULE_TAG,
+        .module_api_version = CAMERA_MODULE_API_VERSION_2_4,
+        .hal_api_version    = HARDWARE_HAL_API_VERSION,
+        .id                 = CAMERA_HARDWARE_MODULE_ID,
+        .name               = "Default USB Camera HAL",
+        .author             = "The Android Open Source Project",
+        .methods            = &gCameraModuleMethods,
+        .dso                = NULL,
+        .reserved           = {0},
     },
-    get_number_of_cameras : get_number_of_cameras,
-    get_camera_info       : get_camera_info,
-    set_callbacks         : set_callbacks,
-    get_vendor_tag_ops    : NULL,
-    open_legacy           : NULL,
-    set_torch_mode        : NULL,
-    init                  : NULL,
-    reserved              : {0},
+    .get_number_of_cameras = get_number_of_cameras,
+    .get_camera_info       = get_camera_info,
+    .set_callbacks         = set_callbacks,
+    .get_vendor_tag_ops    = NULL,
+    .open_legacy           = NULL,
+    .set_torch_mode        = NULL,
+    .init                  = NULL,
+    .reserved              = {0},
 };
 } // extern "C"
 
diff --git a/modules/usbcamera/HotplugThread.cpp b/modules/usbcamera/HotplugThread.cpp
index 6c65086..02e7167 100644
--- a/modules/usbcamera/HotplugThread.cpp
+++ b/modules/usbcamera/HotplugThread.cpp
@@ -39,6 +39,7 @@
 }
 
 bool HotplugThread::threadLoop() {
+    (void)mModule;  // silence warning about unused member.
 
     /**
      * Check camera connection status change, if connected, do below:
diff --git a/modules/usbcamera/Stream.cpp b/modules/usbcamera/Stream.cpp
index f56866e..2b83421 100644
--- a/modules/usbcamera/Stream.cpp
+++ b/modules/usbcamera/Stream.cpp
@@ -170,10 +170,9 @@
     // ToDo: prettyprint usage mask flags
     dprintf(fd, "Gralloc Usage Mask: %#" PRIx32 "\n", mStream->usage);
     dprintf(fd, "Max Buffer Count: %" PRIu32 "\n", mStream->max_buffers);
-    dprintf(fd, "Number of Buffers in use by HAL: %" PRIu32 "\n", mBuffers.size());
+    dprintf(fd, "Number of Buffers in use by HAL: %zu\n", mBuffers.size());
     for (size_t i = 0; i < mBuffers.size(); i++) {
-        dprintf(fd, "Buffer %" PRIu32 "/%" PRIu32 ": %p\n", i, mBuffers.size(),
-                mBuffers[i]);
+        dprintf(fd, "Buffer %zu/%zu: %p\n", i, mBuffers.size(), mBuffers[i]);
     }
 }
 
diff --git a/modules/usbcamera/UsbCamera.cpp b/modules/usbcamera/UsbCamera.cpp
index d0aaded..9d53fc6 100644
--- a/modules/usbcamera/UsbCamera.cpp
+++ b/modules/usbcamera/UsbCamera.cpp
@@ -313,7 +313,7 @@
     return setTemplate(CAMERA3_TEMPLATE_MANUAL, m.get());
 }
 
-bool UsbCamera::isValidCaptureSettings(const camera_metadata_t* settings) {
+bool UsbCamera::isValidCaptureSettings(const camera_metadata_t* /*settings*/) {
     // TODO: reject settings that cannot be captured
     return true;
 }