sm6375-common: Set Bluetooth MAC address using persist property

The idea is to allow us to not depend on stock QTI Bluetooth HAL, as MAC
addresses fetched from NVRAM by nv_mac script will be saved as hex-encoded
files. We can decode back saved files to then the Bluetooth one be set using
persist property so it can be read by Bluetooth HAL.

This is loosely based on similar techniques used on Mi 9 and ZenFone Max Pro M2.

Signed-off-by: Albert I <kras@raphielgang.org>
Change-Id: I74d07c3c3125a04962c37fe8bfcc8385d1fd3398

holi.mk

@@ -375,6 +375,7 @@ PRODUCT_PACKAGES += \
 PRODUCT_PACKAGES += \
     init.batterysecret.rc \
     init.class_main.sh \
+    init.mi.btmac.sh \
     init.kernel.post_boot.sh \
     init.kernel.post_boot-blair.sh \
     init.kernel.post_boot-holi.sh \

rootdir/Android.mk

@@ -9,6 +9,15 @@ LOCAL_SRC_FILES    := bin/init.class_main.sh
 LOCAL_MODULE_PATH  := $(TARGET_OUT_VENDOR_EXECUTABLES)
 include $(BUILD_PREBUILT)
 
+include $(CLEAR_VARS)
+LOCAL_MODULE       := init.mi.btmac.sh
+LOCAL_MODULE_TAGS  := optional
+LOCAL_MODULE_CLASS := ETC
+LOCAL_SRC_FILES    := bin/init.mi.btmac.sh
+LOCAL_MODULE_PATH  := $(TARGET_OUT_VENDOR_EXECUTABLES)
+include $(BUILD_PREBUILT)
+
+
 include $(CLEAR_VARS)
 LOCAL_MODULE       := init.kernel.post_boot.sh
 LOCAL_MODULE_TAGS  := optional

rootdir/bin/init.mi.btmac.sh

@@ -0,0 +1,21 @@
+#!/vendor/bin/sh
+# Copyright (C) 2021 KudProject Development
+# SPDX-License-Identifier: GPL-3.0-or-later OR Apache-2.0
+
+LOG_TAG="MiSetBtMac"
+logi () { log -t "$LOG_TAG" -p i "$@"; }
+
+# hex binary containing mac address
+BT_MAC_HEX_PATH="/data/vendor/mac_addr/bt.mac";
+if [ ! -f "$BT_MAC_HEX_PATH" ]; then
+    logi "bt.mac file not found, exiting"
+    exit
+fi
+
+# raw mac address without colons
+RAW_MAC=$(xxd -p "$BT_MAC_HEX_PATH");
+# convert it into format recognized by bluetooth hal
+DEC_MAC=$(echo "$RAW_MAC" | sed 's!^M$!!;s!\-!!g;s!\.!!g;s!\(..\)!\1:!g;s!:$!!')
+# set the mac address using persist property
+setprop persist.vendor.service.bdroid.bdaddr "$DEC_MAC"
+logi "bt.mac file found, setting mac addr"

rootdir/etc/init.target.rc

@@ -259,6 +259,16 @@ service svi_on /vendor/bin/ppd "svi:on"
     oneshot
     disabled
 
+on property:init.svc.vendor.nv_mac=stopped
+    start vendor.btmac-sh
+
+service vendor.btmac-sh /vendor/bin/init.mi.btmac.sh
+    class late_start
+    user system
+    group system bluetooth wifi
+    oneshot
+    disabled
+
 on property:ro.vendor.display.svi=1 && property:sys.boot_completed=1
     start svi_on
 	

sepolicy/vendor/file_contexts

@@ -9,6 +9,9 @@
 /vendor/bin/batterysecret								u:object_r:batterysecret_exec:s0
 /mnt/vendor/persist/subsys(/.*)?							u:object_r:persist_subsys_file:s0
 
+# Bluetooth
+/vendor/bin/init\.mi\.btmac\.sh								u:object_r:vendor_qti_init_shell_exec:s0
+
 # Camera
 /mnt/vendor/persist/camera(/.*)?							u:object_r:camera_persist_file:s0
 

sepolicy/vendor/vendor_qti_init_shell.te

@@ -0,0 +1,4 @@
+# allow init.mi.btmac.sh to read hex-encoded mac address and set it
+allow vendor_qti_init_shell vendor_bluetooth_prop:property_service set;
+allow vendor_qti_init_shell vendor_wifi_vendor_data_file:dir search;
+allow vendor_qti_init_shell vendor_wifi_vendor_data_file:file r_file_perms;