sweet: override the SetRefreshRate HWC builtin display function

* This function causes the refresh rate to change randomly, and
  produces flickering on the display

* Override the original function by renaming the symbol so linker
  uses the symbol from the shim instead of the original library's
  symbol

Signed-off-by: daniml3 <daniel@danielml.dev>
Change-Id: I2fa6b3f834df79c32d22f5a057da2108cc9cacab

device.mk

@@ -39,6 +39,9 @@ PRODUCT_PACKAGES += \
 PRODUCT_COPY_FILES += \
     $(LOCAL_PATH)/configs/display/qdcm_calib_data_xiaomi_k6_38_0c_0a_fhd_dsc_video_dsi_panel.xml:$(TARGET_COPY_OUT_VENDOR)/etc/qdcm_calib_data_xiaomi_k6_38_0c_0a_fhd_dsc_video_dsi_panel.xml
 
+PRODUCT_PACKAGES += \
+    libsdmcore-shim
+
 # Fstab
 PRODUCT_COPY_FILES += \
     $(LOCAL_PATH)/rootdir/etc/fstab.qcom:$(TARGET_COPY_OUT_RAMDISK)/fstab.qcom \

display/Android.bp

@@ -0,0 +1,8 @@
+cc_library_shared {
+    name: "libsdmcore-shim",
+    srcs: [
+        "display_builtin.cpp"
+    ],
+    required: ["libsdmcore-patch"],
+    vendor: true,
+}

display/Android.mk

@@ -0,0 +1,24 @@
+LOCAL_PATH := $(call my-dir)
+
+HWC := hwcomposer.$(TARGET_BOARD_PLATFORM)
+LIBSDMCORE := $(TARGET_OUT_VENDOR)/lib64/libsdmcore.so
+HWCOMPOSER := $(TARGET_OUT_VENDOR)/lib64/hw/$(HWC).so
+
+ORIGINAL_SYMBOL := _ZN3sdm14DisplayBuiltIn14SetRefreshRateEjb
+CUSTOM_SYMBOL := _ZN3sdm14DisplayBuiltIn14SetRefreshCustEjb
+
+include $(CLEAR_VARS)
+LOCAL_MODULE := libsdmcore-patch
+LOCAL_PREBUILT_MODULE_FILE := /dev/null
+LOCAL_MODULE_CLASS := ETC
+LOCAL_VENDOR_MODULE := true
+LOCAL_REQUIRED_MODULES := $(HWC) libsdmcore
+
+LOCAL_POST_INSTALL_CMD := \
+    cp $(PRODUCT_OUT)/symbols/vendor/lib64/libsdmcore.so $(LIBSDMCORE) && \
+    cp $(PRODUCT_OUT)/symbols/vendor/lib64/hw/$(HWC).so $(HWCOMPOSER) && \
+    sed -i s/$(ORIGINAL_SYMBOL)/$(CUSTOM_SYMBOL)/g $(LIBSDMCORE) && \
+    sed -i s/libdisplaydebug/libsdmcore-shim/g $(HWCOMPOSER) && \
+    rm $(TARGET_OUT_VENDOR)/etc/$(LOCAL_MODULE)
+
+include $(BUILD_PREBUILT)

display/display_builtin.cpp

@@ -0,0 +1,3 @@
+#include <stdint.h>
+
+extern "C" void _ZN3sdm14DisplayBuiltIn14SetRefreshCustEjb(uint32_t, bool) {}