sdm710-common: Implement AntiFlicker LiveDisplay HAL

* Implement AntiFlicker using 'dc_dimming' sysfs knob

Change-Id: I59c179e75eca4159b5e6407379b064f0a67540a8

livedisplay/Android.bp

@@ -20,6 +20,7 @@ cc_binary {
     init_rc: ["vendor.lineage.livedisplay@2.1-service.sdm710.rc"],
     relative_install_path: "hw",
     srcs: [
+        "AntiFlicker.cpp",
         "SunlightEnhancement.cpp",
         "service.cpp",
     ],

livedisplay/AntiFlicker.cpp

@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2022 The LineageOS Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "AntiFlickerService"
+
+#include <fstream>
+#include <android-base/file.h>
+#include <android-base/logging.h>
+#include <android-base/strings.h>
+
+#include "AntiFlicker.h"
+
+namespace vendor {
+namespace lineage {
+namespace livedisplay {
+namespace V2_1 {
+namespace implementation {
+
+static constexpr const char* kDcDimmingPath = "/sys/devices/platform/soc/soc:qcom,dsi-display-primary/dc_dimming";
+
+bool AntiFlicker::isSupported() {
+    std::ofstream dc_dimming_file(kDcDimmingPath);
+    if (!dc_dimming_file.is_open()) {
+        LOG(ERROR) << "Failed to open " << kDcDimmingPath << ", error=" << errno
+                   << " (" << strerror(errno) << ")";
+    }
+    return !dc_dimming_file.fail();
+}
+
+Return<bool> AntiFlicker::isEnabled() {
+    std::ifstream dc_dimming_file(kDcDimmingPath);
+    int result = -1;
+    dc_dimming_file >> result;
+    return !dc_dimming_file.fail() && result > 0;
+}
+
+Return<bool> AntiFlicker::setEnabled(bool enabled) {
+    std::ofstream dc_dimming_file(kDcDimmingPath);
+    dc_dimming_file << (enabled ? '1' : '0');
+    if (dc_dimming_file.fail())
+        LOG(ERROR) << "Failed to write " << kDcDimmingPath;
+    return !dc_dimming_file.fail();
+}
+
+}  // namespace implementation
+}  // namespace V2_1
+}  // namespace livedisplay
+}  // namespace lineage
+}  // namespace vendor

livedisplay/AntiFlicker.h

@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2019-2020 The LineageOS Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <hidl/MQDescriptor.h>
+#include <hidl/Status.h>
+#include <vendor/lineage/livedisplay/2.1/IAntiFlicker.h>
+
+namespace vendor {
+namespace lineage {
+namespace livedisplay {
+namespace V2_1 {
+namespace implementation {
+
+using ::android::hardware::Return;
+
+class AntiFlicker : public IAntiFlicker {
+  public:
+    bool isSupported();
+
+    // Methods from ::vendor::lineage::livedisplay::V2_1::IAntiFlicker follow.
+    Return<bool> isEnabled() override;
+    Return<bool> setEnabled(bool enabled) override;
+};
+
+}  // namespace implementation
+}  // namespace V2_1
+}  // namespace livedisplay
+}  // namespace lineage
+}  // namespace vendor

livedisplay/service.cpp

@@ -19,15 +19,25 @@
 #include <android-base/logging.h>
 #include <binder/ProcessState.h>
 #include <hidl/HidlTransportSupport.h>
+#include "AntiFlicker.h"
 #include "SunlightEnhancement.h"
 
+using ::vendor::lineage::livedisplay::V2_1::implementation::AntiFlicker;
 using ::vendor::lineage::livedisplay::V2_1::implementation::SunlightEnhancement;
 
 int main() {
     android::sp<SunlightEnhancement> sunlightEnhancement = new SunlightEnhancement();
+    android::sp<AntiFlicker> antiFlicker = new AntiFlicker();
 
     android::hardware::configureRpcThreadpool(1, true /*callerWillJoin*/);
 
+    if (antiFlicker->isSupported()) {
+        if (antiFlicker->registerAsService() != android::OK) {
+            LOG(ERROR) << "Cannot register antiflicker HAL service.";
+            return 1;
+        }
+    }
+
     if (sunlightEnhancement->isSupported()) {
         if (sunlightEnhancement->registerAsService() != android::OK) {
             LOG(ERROR) << "Cannot register sunlight enhancement HAL service.";

livedisplay/vendor.lineage.livedisplay@2.1-service.sdm710.rc

@@ -1,4 +1,5 @@
 on boot
+    chown system system /sys/devices/platform/soc/soc:qcom,dsi-display-primary/dc_dimming
     chown system system /sys/devices/platform/soc/soc:qcom,dsi-display-primary/hbm
 
 service vendor.livedisplay-hal-2-1 /vendor/bin/hw/vendor.lineage.livedisplay@2.1-service.sdm710

livedisplay/vendor.lineage.livedisplay@2.1-service.sdm710.xml

@@ -2,6 +2,7 @@
     <hal format="hidl">
         <name>vendor.lineage.livedisplay</name>
         <transport>hwbinder</transport>
+        <fqname>@2.1::IAntiFlicker/default</fqname>
         <fqname>@2.1::ISunlightEnhancement/default</fqname>
     </hal>
 </manifest>