Hi,
Could you please tell me how to find out, which driver is used by the Linux system in my PC to communicate with the serial port?
Thank you.

Serial as in RS-232?

The driver for those are a part of the kernel itself - to use the ports programs read or write to /dev/ttySx where x is the number of the serial port, so the first port in the system would be /dev/ttyS0 the second ttyS1 and so on.

Hope this helps!

Actually i wanted to know which files in the Linux kernel source are used for implementing the driver for the serial port. As there are different .c files in the kernel under the "drivers/serial" directory, how can i find out which are the relevant files to browse?
does "lsmod" output give this information?

i did a "dmesg" and browsed the output. i found the following:

Serial driver version 5.05c (2001-07-08) with MANY_PORTS MULTIPORT SHARE_IRQ SERIAL_PCI ISAPNP enabled
ttyS0 at 0x03f8 (irq = 4) is a 16550A
ttyS1 at 0x02f8 (irq = 3) is a 16550A

Does this mean 8250.c is the only file to look at?(by the way there are many 8250*.c in the folder)
Thank you.