Doubts about vt tty driver

[Chinmay Bapat]

Hi
I am trying to understand the vt tty driver.
I have been trying to read the code and have been referring to Linux Device
Drivers book. I have read this
http://www.linusakesson.net/programming/ttyto get an idea of what ttys
are etc.

I have many doubts and would be very greatful if someone could help me out.

I am not sure where this driver fits into the rest of things. I mean, from
where are the functions in this driver called, and what does the driver
actually do? Does it interact with the screen hardware? If it does, how?

>From what I understand, the vt driver does the work of the 'Terminal
emulator' in this http://www.linusakesson.net/programming/tty/case3.png .
Am I right?

The LDD3 book says that after the driver registers itself, it registers the
devices it controls through the tty_register_device function. But I cannot
see this being done in the vt.c file.   Why?

Also, there are two functions con_write and vt_console_print that write. I
was told that vt_console_print is high level. It is called by the console
code. con_write  is low level. It writes to the tty. But I still cannot
understand what each one does. Also I do not know how to find out from
where these functions are called: con_write is assigned to .write of the
struct  tty_operations con_ops, vt_console_print .write of struct console
vt_console_driver. But from where are these .write s called?

This is the first time I am working with a driver or anything to do with
the kernel, so even if my doubts are stupid please help me out.
Thank you.

--
Regards,
Chinmay Bapat
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