sources

(ordered chronologically by access time)

• Kbuild object variable name rationale
• Kbuild kernel module setup guide
• struct file_operations documentation, also
  • write(2)
  • read(2)
• (Sadly) the Linux kernel source itself, especially
  • drivers/char/random.c
  • drivers/char/mem.c
• Linux kernel labs - character device drivers
• Core API
• Driver API

tips

• When the kernel documentation references manpages, these actually contain useful information. Manpages are not only for commands, but also include detailed documentation for the syscall interface and other C APIs.

  Since most of the manpages referenced by the kernel are from section 2 (on system calls), you should append the number between brackets to the man command, i.e. to read 'write(2)' use the command man 2 write.

• Use dmesg with the -w or -W option (see man dmesg(1))