diff --git a/.ci/.common.sh b/.ci/.common.sh
index 0183aba..21c2b28 100644
--- a/.ci/.common.sh
+++ b/.ci/.common.sh
@@ -1,7 +1,7 @@
 INCLUDE_DIRS="-I. -I../libdrm/include/drm -Iinclude -I/usr/include/libdrm -I./.ci/android_headers -I./tests/test_include"
 
-CLANG="clang++-11"
-CLANG_TIDY="clang-tidy-11"
+CLANG="clang++-12"
+CLANG_TIDY="clang-tidy-12"
 
 CXXARGS="-fPIC -Wall -Werror -DPLATFORM_SDK_VERSION=30 -D__ANDROID_API__=30 -Wsign-promo -Wimplicit-fallthrough"
 CXXARGS+=" -D_LIBCPP_ENABLE_THREAD_SAFETY_ANNOTATIONS -Wno-gnu-include-next "
diff --git a/.ci/.gitlab-ci-clang-tidy-coarse.sh b/.ci/.gitlab-ci-clang-tidy-coarse.sh
index de0c024..3f98150 100755
--- a/.ci/.gitlab-ci-clang-tidy-coarse.sh
+++ b/.ci/.gitlab-ci-clang-tidy-coarse.sh
@@ -17,6 +17,7 @@
 TIDY_COARSE_CHECKS+="-google-readability-braces-around-statements,"
 TIDY_COARSE_CHECKS+="-google-readability-casting,"
 TIDY_COARSE_CHECKS+="misc-*,"
+TIDY_COARSE_CHECKS+="-misc-non-private-member-variables-in-classes",
 TIDY_COARSE_CHECKS+="modernize-*,"
 TIDY_COARSE_CHECKS+="-modernize-avoid-c-arrays,"
 TIDY_COARSE_CHECKS+="-modernize-use-trailing-return-type,"
@@ -24,6 +25,7 @@
 TIDY_COARSE_CHECKS+="portability-*,"
 TIDY_COARSE_CHECKS+="readability-*,"
 TIDY_COARSE_CHECKS+="-readability-braces-around-statements,"
+TIDY_COARSE_CHECKS+="-readability-function-cognitive-complexity,"
 TIDY_COARSE_CHECKS+="-readability-convert-member-functions-to-static,"
 TIDY_COARSE_CHECKS+="-readability-implicit-bool-conversion,"
 TIDY_COARSE_CHECKS+="-readability-magic-numbers,"
diff --git a/.clang-tidy b/.clang-tidy
index 0bb7bf0..6cdbdc0 100644
--- a/.clang-tidy
+++ b/.clang-tidy
@@ -6,6 +6,7 @@
     *,
     -fuchsia*,
     -llvm*,
+    -concurrency-mt-unsafe,
     -cppcoreguidelines-pro-type-vararg, -hicpp-vararg,
     -hicpp-signed-bitwise,
 
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 04eb6c5..41d38ba 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,8 +1,11 @@
-image: ubuntu:20.10
+image: ubuntu:21.04
+
+variables:
+  DEBIAN_FRONTEND: noninteractive
 
 before_script:
   - apt-get --quiet update --yes >/dev/null
-  - apt-get --quiet install --yes clang-11 clang-tidy-11 clang-format-11 git libdrm-dev blueprint-tools libgtest-dev >/dev/null
+  - apt-get --quiet install --yes clang-12 clang-tidy-12 clang-format-12 git libdrm-dev blueprint-tools libgtest-dev >/dev/null
 
 stages:
   - build
diff --git a/DrmHwcTwo.cpp b/DrmHwcTwo.cpp
index 02667cf..d9ba4f3 100644
--- a/DrmHwcTwo.cpp
+++ b/DrmHwcTwo.cpp
@@ -48,7 +48,7 @@
 
 HWC2::Error DrmHwcTwo::CreateDisplay(hwc2_display_t displ,
                                      HWC2::DisplayType type) {
-  DrmDevice *drm = resource_manager_.GetDrmDevice(displ);
+  DrmDevice *drm = resource_manager_.GetDrmDevice(static_cast<int>(displ));
   if (!drm) {
     ALOGE("Failed to get a valid drmresource");
     return HWC2::Error::NoResources;
@@ -413,22 +413,26 @@
   auto attribute = static_cast<HWC2::Attribute>(attribute_in);
   switch (attribute) {
     case HWC2::Attribute::Width:
-      *value = mode->h_display();
+      *value = static_cast<int>(mode->h_display());
       break;
     case HWC2::Attribute::Height:
-      *value = mode->v_display();
+      *value = static_cast<int>(mode->v_display());
       break;
     case HWC2::Attribute::VsyncPeriod:
       // in nanoseconds
-      *value = 1000.0 * 1000.0 * 1000.0 / mode->v_refresh();
+      *value = static_cast<int>(1E9 / mode->v_refresh());
       break;
     case HWC2::Attribute::DpiX:
       // Dots per 1000 inches
-      *value = mm_width ? (mode->h_display() * kUmPerInch) / mm_width : -1;
+      *value = mm_width
+                   ? static_cast<int>(mode->h_display() * kUmPerInch / mm_width)
+                   : -1;
       break;
     case HWC2::Attribute::DpiY:
       // Dots per 1000 inches
-      *value = mm_height ? (mode->v_display() * kUmPerInch) / mm_height : -1;
+      *value = mm_height ? static_cast<int>(mode->v_display() * kUmPerInch /
+                                            mm_height)
+                         : -1;
       break;
 #if PLATFORM_SDK_VERSION > 29
     case HWC2::Attribute::ConfigGroup:
@@ -786,8 +790,8 @@
 
   hwc_frect_t source_crop = {.left = 0.0F,
                              .top = 0.0F,
-                             .right = bo.width + 0.0F,
-                             .bottom = bo.height + 0.0F};
+                             .right = static_cast<float>(bo.width),
+                             .bottom = static_cast<float>(bo.height)};
   client_layer_.SetLayerSourceCrop(source_crop);
 
   return HWC2::Error::None;
@@ -909,7 +913,7 @@
   if (mode.id() == 0)
     return HWC2::Error::BadConfig;
 
-  *outVsyncPeriod = 1E9 / mode.v_refresh();
+  *outVsyncPeriod = static_cast<hwc2_vsync_period_t>(1E9 / mode.v_refresh());
   return HWC2::Error::None;
 }
 
diff --git a/README.md b/README.md
index 728bc76..c142266 100644
--- a/README.md
+++ b/README.md
@@ -16,7 +16,7 @@
   you with formatting of your patches:
 
     ```
-    git diff | clang-format-diff-11 -p 1 -style=file
+    git diff | clang-format-diff-12 -p 1 -style=file
     ```
 
 * Hardware specific changes should be tested on relevant platforms before
diff --git a/bufferinfo/legacy/BufferInfoLibdrm.cpp b/bufferinfo/legacy/BufferInfoLibdrm.cpp
index 52f792f..da89eb5 100644
--- a/bufferinfo/legacy/BufferInfoLibdrm.cpp
+++ b/bufferinfo/legacy/BufferInfoLibdrm.cpp
@@ -37,9 +37,9 @@
 
 struct DroidYuvFormat {
   /* Lookup keys */
-  int native;                     /* HAL_PIXEL_FORMAT_ */
+  uint32_t native;                /* HAL_PIXEL_FORMAT_ */
   enum chroma_order chroma_order; /* chroma order is {Cb, Cr} or {Cr, Cb} */
-  int chroma_step; /* Distance in bytes between subsequent chroma pixels. */
+  size_t chroma_step; /* Distance in bytes between subsequent chroma pixels. */
 
   /* Result */
   int fourcc; /* DRM_FORMAT_ */
@@ -64,8 +64,8 @@
 
 #define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
 
-static int get_fourcc_yuv(int native, enum chroma_order chroma_order,
-                          int chroma_step) {
+static int get_fourcc_yuv(uint32_t native, enum chroma_order chroma_order,
+                          size_t chroma_step) {
   for (auto droid_yuv_format : kDroidYuvFormats)
     if (droid_yuv_format.native == native &&
         droid_yuv_format.chroma_order == chroma_order &&
@@ -75,7 +75,7 @@
   return -1;
 }
 
-static bool is_yuv(int native) {
+static bool is_yuv(uint32_t native) {
   for (auto droid_yuv_format : kDroidYuvFormats)
     if (droid_yuv_format.native == native)
       return true;
diff --git a/compositor/DrmDisplayComposition.cpp b/compositor/DrmDisplayComposition.cpp
index 49dff0e..47f669d 100644
--- a/compositor/DrmDisplayComposition.cpp
+++ b/compositor/DrmDisplayComposition.cpp
@@ -145,7 +145,7 @@
   }
 }
 
-static const char *DPMSModeToString(int dpms_mode) {
+static const char *DPMSModeToString(uint32_t dpms_mode) {
   switch (dpms_mode) {
     case DRM_MODE_DPMS_ON:
       return "ON";
diff --git a/compositor/DrmDisplayCompositor.cpp b/compositor/DrmDisplayCompositor.cpp
index a1fe50f..ff9f6ad 100644
--- a/compositor/DrmDisplayCompositor.cpp
+++ b/compositor/DrmDisplayCompositor.cpp
@@ -263,7 +263,7 @@
     DrmPlane *plane = comp_plane.plane();
     std::vector<size_t> &source_layers = comp_plane.source_layers();
 
-    int fb_id = -1;
+    uint32_t fb_id = UINT32_MAX;
     int fence_fd = -1;
     hwc_rect_t display_frame;
     hwc_frect_t source_crop;
@@ -346,7 +346,7 @@
         rotation |= DRM_MODE_ROTATE_0;
 
       if (fence_fd >= 0) {
-        int prop_id = plane->in_fence_fd_property().id();
+        uint32_t prop_id = plane->in_fence_fd_property().id();
         if (prop_id == 0) {
           ALOGE("Failed to get IN_FENCE_FD property id");
           break;
@@ -399,7 +399,7 @@
     }
 
     // Disable the plane if there's no framebuffer
-    if (fb_id < 0) {
+    if (fb_id == UINT32_MAX) {
       ret = drmModeAtomicAddProperty(pset, plane->id(),
                                      plane->crtc_property().id(), 0) < 0 ||
             drmModeAtomicAddProperty(pset, plane->id(),
@@ -754,7 +754,9 @@
 
   uint64_t cur_ts = ts.tv_sec * 1000 * 1000 * 1000 + ts.tv_nsec;
   uint64_t num_ms = (cur_ts - dump_last_timestamp_ns_) / (1000 * 1000);
-  float fps = num_ms ? (num_frames * 1000.0F) / (num_ms) : 0.0F;
+  float fps = num_ms ? static_cast<float>(num_frames) * 1000.0F /
+                           static_cast<float>(num_ms)
+                     : 0.0F;
 
   *out << "--DrmDisplayCompositor[" << display_
        << "]: num_frames=" << num_frames << " num_ms=" << num_ms
diff --git a/drm/DrmDevice.cpp b/drm/DrmDevice.cpp
index abc8edc..570b676 100644
--- a/drm/DrmDevice.cpp
+++ b/drm/DrmDevice.cpp
@@ -195,7 +195,7 @@
     crtcs_.emplace_back(std::move(crtc));
   }
 
-  std::vector<int> possible_clones;
+  std::vector<uint32_t> possible_clones;
   for (int i = 0; !ret && i < res->count_encoders; ++i) {
     drmModeEncoderPtr e = drmModeGetEncoder(fd(), res->encoders[i]);
     if (!e) {
diff --git a/drm/DrmEventListener.cpp b/drm/DrmEventListener.cpp
index b303653..53e7032 100644
--- a/drm/DrmEventListener.cpp
+++ b/drm/DrmEventListener.cpp
@@ -84,7 +84,7 @@
 
 void DrmEventListener::UEventHandler() {
   char buffer[1024];
-  int ret = 0;
+  ssize_t ret = 0;
 
   struct timespec ts {};
 
@@ -93,7 +93,7 @@
   if (!ret)
     timestamp = ts.tv_sec * 1000 * 1000 * 1000 + ts.tv_nsec;
   else
-    ALOGE("Failed to get monotonic clock on hotplug %d", ret);
+    ALOGE("Failed to get monotonic clock on hotplug %zd", ret);
 
   while (true) {
     ret = read(uevent_fd_.Get(), &buffer, sizeof(buffer));
@@ -101,7 +101,7 @@
       return;
 
     if (ret < 0) {
-      ALOGE("Got error reading uevent %d", ret);
+      ALOGE("Got error reading uevent %zd", ret);
       return;
     }
 
diff --git a/drm/DrmMode.cpp b/drm/DrmMode.cpp
index dd25758..c714458 100644
--- a/drm/DrmMode.cpp
+++ b/drm/DrmMode.cpp
@@ -121,7 +121,7 @@
 
 float DrmMode::v_refresh() const {
   // Always recalculate refresh to report correct float rate
-  return clock_ / (float)(v_total_ * h_total_) * 1000.0F;
+  return static_cast<float>(clock_) / (float)(v_total_ * h_total_) * 1000.0F;
 }
 
 uint32_t DrmMode::flags() const {
diff --git a/drm/VSyncWorker.cpp b/drm/VSyncWorker.cpp
index 25eeeab..1c0de21 100644
--- a/drm/VSyncWorker.cpp
+++ b/drm/VSyncWorker.cpp
@@ -104,7 +104,8 @@
     ALOGW("Vsync worker active with conn=%p refresh=%f\n", conn,
           conn ? conn->active_mode().v_refresh() : 0.0F);
 
-  int64_t phased_timestamp = GetPhasedVSync(kOneSecondNs / refresh,
+  int64_t phased_timestamp = GetPhasedVSync(kOneSecondNs /
+                                                static_cast<int>(refresh),
                                             vsync.tv_sec * kOneSecondNs +
                                                 vsync.tv_nsec);
   vsync.tv_sec = phased_timestamp / kOneSecondNs;
diff --git a/include/drmhwcgralloc.h b/include/drmhwcgralloc.h
index db54802..57685d1 100644
--- a/include/drmhwcgralloc.h
+++ b/include/drmhwcgralloc.h
@@ -28,7 +28,7 @@
   uint32_t usage;
   uint32_t pitches[HWC_DRM_BO_MAX_PLANES];
   uint32_t offsets[HWC_DRM_BO_MAX_PLANES];
-  uint32_t prime_fds[HWC_DRM_BO_MAX_PLANES];
+  int prime_fds[HWC_DRM_BO_MAX_PLANES];
   uint64_t modifiers[HWC_DRM_BO_MAX_PLANES];
   int acquire_fence_fd;
 } hwc_drm_bo_t;
diff --git a/utils/properties.h b/utils/properties.h
index 607cbc5..38a2762 100644
--- a/utils/properties.h
+++ b/utils/properties.h
@@ -20,7 +20,7 @@
   if (prop == nullptr) {
     snprintf(value, PROPERTY_VALUE_MAX, "%s", default_value);
   }
-  return strlen(value);
+  return static_cast<int>(strlen(value));
 }
 
 #endif