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Title: How to add a module to android Kernel [Print This Page]

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Author: Orion    Time: 1/7/2018 07:43
Title: How to add a module to android Kernel
Hello im new to making modules for android/linux so i apologize if these are obvious questions but ive been having trouble with getting this to work properly.

Ive been trying to add a simple hello module to the android kernel. here are my current steps:
HelloModule.c:

1. #include <linux/module.h>
   
2. #include <linux/kernel.h>
   
3. #include <linux/init.h>
   
4. 
   
5. static int __init hello_module(void)
   
6. {
   
7.         printk(KERN_INFO "Hello android kernel...\n");
   
8.         return 0;
   
9. }
   
10. 
    
11. static void __exit goodbye_module(void)
    
12. {
    
13. printk(KERN_INFO "Goodbye android kernel...\n");
    
14. }
    
15. 
    
16. module_init(hello_module);
    
17. module_exit(goodbye_module);

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1. move hellomodule.c to firefly-rk3399/kernel/drivers/misc/
2. add to makefile (in misc):

1. obj-$(CONFIG_HELLO_MODULE)      += HelloModule.o

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3.add to Kconfig(in misc):

1. config HELLO_MODULE
   
2.         tristate "Hello Module"
   
3.         default y

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4. cd firefly-rk3399/
5. ./FFtools/make.sh -j32
6. ./FFtools/mkupdate/mkupdate.sh
7. sudo upgade_tool uf ./rockdev/Image-rk3399_firefly_box/Firefly-RK3399_Android7.1.1_MP_180106.img

It looks like hellomodule.o was compiled correctly in /misc directory
The diffrences between android kernel and a normal linux kernel have been giving me trouble, So heres my questions:
1. is there  a way to see the installed modules on android adb shell? (lsmod doesnt work )
2. how do you run hellomodule in this case? (modprobe doesnt work)
3. im trying to run

1. make ARCH=arm64 CROSS_COMPILE=?

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to make a .ko for hellomodule.c by itselfWhere is the cross compiler for the rk3399 board?

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