Accessing a serial port from a linux kernel module

Hello Linux Kernel Driver Gurus!

I'm writing a v4l2 driver for a camera that uses a serial interface for configuration. I'd like the driver to configure the camera, as it keeps the client code consistent across camera models. The question is: what's the best way to access the camera's serial interface from the driver module?

From what I hear, accessing files from a kernel driver is a big no-no, but it can be done. As such, I'm currently using the following code snippet, but it feels like a hack.

oldfs = get_fs();
set_fs(KERNEL_DS);

fd->f_pos=0;
fd->f_op->write(fd, data, data_len, &fd->f_pos);

set_fs(oldfs);

My question is really: what's the right way to do this?