commit 0072a34c2ee4b203306f8bb096426c85699c9d00
author Sushil Chauhan <sushilchauhan@codeaurora.org> Fri Jul 12 14:54:29 2019 -0700
committer Gerrit - the friendly Code Review server <code-review@localhost> Thu Apr 09 04:29:43 2020 -0700
tree 702ce2c3fb5a763589dc3a1060e187b32b33c3ff
parent e5f55a1288899c0051a597d9b1ac03a87d65f4c9

sdm: Don't block draw-cycle thread during SetDisplayBrightness

Driver makes sure that Panel commands are serialized to any frame
update on Panel. SetDisplayBrightness API doesn't need to acquire
locker_ lock which blocks draw-cycle thread and causes frame drops.
Define brightness_lock_ to serialize Set and Get Panel brightness

CRs-Fixed: 2446089
Change-Id: I963f1b3ddcd4765ddff805a373f70cdd550fa993

sdm/libs/core/display_builtin.cpp

diff --git a/sdm/libs/core/display_builtin.cpp b/sdm/libs/core/display_builtin.cpp
index 0e3ff35..25af21e 100644
--- a/sdm/libs/core/display_builtin.cpp
+++ b/sdm/libs/core/display_builtin.cpp
@@ -347,7 +347,7 @@
 }
 
 DisplayError DisplayBuiltIn::SetPanelBrightness(float brightness) {
-  lock_guard<recursive_mutex> obj(recursive_mutex_);
+  lock_guard<recursive_mutex> obj(brightness_lock_);
 
   if (brightness != -1.0f && !(0.0f <= brightness && brightness <= 1.0f)) {
     DLOGE("Bad brightness value = %f", brightness);
@@ -496,7 +496,7 @@
 }
 
 DisplayError DisplayBuiltIn::GetPanelBrightness(float *brightness) {
-  lock_guard<recursive_mutex> obj(recursive_mutex_);
+  lock_guard<recursive_mutex> obj(brightness_lock_);
 
   DisplayError err = kErrorNone;
   int level = 0;

sdm/libs/core/display_builtin.h

diff --git a/sdm/libs/core/display_builtin.h b/sdm/libs/core/display_builtin.h
index fde57e1..a6a272e 100644
--- a/sdm/libs/core/display_builtin.h
+++ b/sdm/libs/core/display_builtin.h
@@ -158,6 +158,7 @@
   int previous_retire_fence_ = -1;
   DeferFpsConfig deferred_config_ = {};
   float level_remainder_ = 0.0f;
+  recursive_mutex brightness_lock_;
 };
 
 }  // namespace sdm

sdm/libs/hwc2/hwc_session.cpp

diff --git a/sdm/libs/hwc2/hwc_session.cpp b/sdm/libs/hwc2/hwc_session.cpp
index d1653ee..87ded3a 100644
--- a/sdm/libs/hwc2/hwc_session.cpp
+++ b/sdm/libs/hwc2/hwc_session.cpp
@@ -3328,7 +3328,22 @@
 
 int32_t HWCSession::SetDisplayBrightness(hwc2_device_t *device, hwc2_display_t display,
                                          float brightness) {
-  return CallDisplayFunction(device, display, &HWCDisplay::SetPanelBrightness, brightness);
+  if (!device) {
+    return HWC2_ERROR_BAD_PARAMETER;
+  }
+
+  if (display >= HWCCallbacks::kNumDisplays) {
+    return HWC2_ERROR_BAD_DISPLAY;
+  }
+
+  HWCSession *hwc_session = static_cast<HWCSession *>(device);
+  HWCDisplay *hwc_display = hwc_session->hwc_display_[display];
+
+  if (!hwc_display) {
+    return HWC2_ERROR_BAD_PARAMETER;
+  }
+
+  return INT32(hwc_display->SetPanelBrightness(brightness));
 }
 
 android::status_t HWCSession::SetQSyncMode(const android::Parcel *input_parcel) {