Broadcom bcmwl driver failed to compile when upgrade to kernel 4.15.0-29 [error: implicit declaration of function ‘init_timer’]

1) lsb-release -a
Distributor ID: neon
Description: KDE neon User Edition 5.13
Release: 16.04
Codename: xenial

2) apt-cache policy bcmwl-kernel-source
bcmwl-kernel-source:
  Installed: 6.30.223.271+bdcom-0ubuntu1~1.2
  Candidate: 6.30.223.271+bdcom-0ubuntu1~1.2
  ...

3) What you expected to happen
  The new kernel installs and dkms modules compile normally

4) What happened instead
This error shows up when upgrade to kernel 4.15.0-29:

Processing triggers for linux-image-4.15.0-29-generic (4.15.0-29.31~16.04.1) ...
/etc/kernel/postinst.d/dkms:
Error! Bad return status for module build on kernel: 4.15.0-29-generic (x86_64)
Consult /var/lib/dkms/bcmwl/6.30.223.271+bdcom/build/make.log for more information.

It seems there are some compilation errors in make.log:

  CC [M] /var/lib/dkms/bcmwl/6.30.223.271+bdcom/build/src/shared/linux_osl.o
/var/lib/dkms/bcmwl/6.30.223.271+bdcom/build/src/shared/linux_osl.c: In function ‘osl_os_get_image_block’:
/var/lib/dkms/bcmwl/6.30.223.271+bdcom/build/src/shared/linux_osl.c:1083:26: warning: passing argument 2 of ‘kernel_read’ makes pointer from integer without a cast [-Wint-conversion]
  rdlen = kernel_read(fp, fp->f_pos, buf, len);
                          ^
In file included from ./include/linux/huge_mm.h:7:0,
                 from ./include/linux/mm.h:463,
                 from /var/lib/dkms/bcmwl/6.30.223.271+bdcom/build/src/include/linuxver.h:65,
                 from /var/lib/dkms/bcmwl/6.30.223.271+bdcom/build/src/shared/linux_osl.c:25:
./include/linux/fs.h:2858:16: note: expected ‘void *’ but argument is of type ‘loff_t {aka long long int}’
 extern ssize_t kernel_read(struct file *, void *, size_t, loff_t *);
                ^
/var/lib/dkms/bcmwl/6.30.223.271+bdcom/build/src/shared/linux_osl.c:1083:37: warning: passing argument 3 of ‘kernel_read’ makes integer from pointer without a cast [-Wint-conversion]
  rdlen = kernel_read(fp, fp->f_pos, buf, len);
                                     ^
In file included from ./include/linux/huge_mm.h:7:0,
                 from ./include/linux/mm.h:463,
                 from /var/lib/dkms/bcmwl/6.30.223.271+bdcom/build/src/include/linuxver.h:65,
                 from /var/lib/dkms/bcmwl/6.30.223.271+bdcom/build/src/shared/linux_osl.c:25:
./include/linux/fs.h:2858:16: note: expected ‘size_t {aka long unsigned int}’ but argument is of type ‘char *’
 extern ssize_t kernel_read(struct file *, void *, size_t, loff_t *);
                ^
/var/lib/dkms/bcmwl/6.30.223.271+bdcom/build/src/shared/linux_osl.c:1083:42: warning: passing argument 4 of ‘kernel_read’ makes pointer from integer without a cast [-Wint-conversion]
  rdlen = kernel_read(fp, fp->f_pos, buf, len);
                                          ^
In file included from ./include/linux/huge_mm.h:7:0,
                 from ./include/linux/mm.h:463,
                 from /var/lib/dkms/bcmwl/6.30.223.271+bdcom/build/src/include/linuxver.h:65,
                 from /var/lib/dkms/bcmwl/6.30.223.271+bdcom/build/src/shared/linux_osl.c:25:
./include/linux/fs.h:2858:16: note: expected ‘loff_t * {aka long long int *}’ but argument is of type ‘int’
 extern ssize_t kernel_read(struct file *, void *, size_t, loff_t *);
                ^
  CC [M] /var/lib/dkms/bcmwl/6.30.223.271+bdcom/build/src/wl/sys/wl_linux.o
/var/lib/dkms/bcmwl/6.30.223.271+bdcom/build/src/wl/sys/wl_linux.c: In function ‘wl_init_timer’:
/var/lib/dkms/bcmwl/6.30.223.271+bdcom/build/src/wl/sys/wl_linux.c:2359:2: error: implicit declaration of function ‘init_timer’ [-Werror=implicit-function-declaration]
  init_timer(&t->timer);
  ^
/var/lib/dkms/bcmwl/6.30.223.271+bdcom/build/src/wl/sys/wl_linux.c:2360:10: error: ‘struct timer_list’ has no member named ‘data’
  t->timer.data = (ulong) t;
          ^
/var/lib/dkms/bcmwl/6.30.223.271+bdcom/build/src/wl/sys/wl_linux.c:2361:20: error: assignment from incompatible pointer type [-Werror=incompatible-pointer-types]
  t->timer.function = wl_timer;
                    ^
cc1: some warnings being treated as errors