Re: ISA slot char driver help.

[Paul Gearon <pag@PISoftware.com>]

On Sat, 6 Jul 2002, Himanshu Sharma wrote:

> I am a student and am trying to design an ISA card.
>
> Can any one of you please mail me a basic char driver for a generic ISA
> card.
>
> Any pointers will also be helpful.

As James Stevenson pointed out, there are lots of drivers in the kernel
which are easy to use as a template.

For a simple card, you'll probably just need to implement the open/close,
read/write, and maybe ioctl functions.  Talking to your card is entirely a
matter of how you've built your hardware.  If it's based on I/O decoding
then you'll want to use inb and outb.  If it's memory mapped, then just
dereference the address.  IRQs are a slightly more complex story, but
there's probably a lot to do before you start looking at those.

It's a little out of date now, but I thought that Ori Pomerantz's "Linux
Kernel Module Programming Guide" was a good introduction.
http://www.tldp.org/LDP/lkmpg/mpg.html

Regards,
Paul Gearon

Software Engineer                Telephone:   +61 7 3876 2188
Plugged In Software              Fax:         +61 7 3876 4899
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