RK3399 Android 7.1系统HAL的camera编译32位动态库

Platform: RK3399
OS: Android 7.1
Board: Firefly-RK3399

需求：

系统HAL的camera库camera.rk30board.so使用的是32位版本的。

而单独编译模块(命令是#make camera.rk30board_32 -j8 )出来却只有64位版本，位于 system/lib64/hw下面。

理论上根据Android.mk的规则应该是32和64都会编译的，不过单独编译模块的时候可能只包含了64位版本的处理。如官方的一句话所说：

Android.mk

ifneq ((strip (TARGET_2ND_ARCH)), )
LOCAL_MULTILIB := both //表示32和64版本都编译
endif

解决方法：

#make camera.rk30board_32 -j8
Build Log:

[ 64% 9/14] target SharedLib: camera.rk30board_32 (out/target/product/rk3399_firefly_edp_box/obj_arm/SHARED_LIBRARIES/camera.rk30board_intermediates/LINKED/camera.rk30board.so)
[ 71% 10/14] target Pack Relocations: camera.rk30board_32 (out/target/product/rk3399_firefly_edp_box/obj_arm/SHARED_LIBRARIES/camera.rk30board_intermediates/PACKED/camera.rk30board.so)
[ 78% 11/14] target Symbolic: camera.rk30board_32 (out/target/product/rk3399_firefly_edp_box/symbols/system/lib/hw/camera.rk30board.so)
[ 85% 12/14] target Strip: camera.rk30board_32 (out/target/product/rk3399_firefly_edp_box/obj_arm/lib/camera.rk30board.so)
[100% 14/14] Install: out/target/product/rk3399_firefly_edp_box/system/lib/hw/camera.rk30board.so
[100% 14/14] build out/target/product/rk3399_firefly_edp_box/obj_arm/lib/camera.rk30board.so.toc

原作者：KrisFei