Ziatech 5503 watchdog driver

[M. Warner Losh]

In message: <20050319080215.GX51688 at smp500.sitetronics.com>
            "Devon H. O'Dell " <dodell at offmyserver.com> writes:
: On Fri, Mar 18, 2005 at 03:55:53PM -0700, Warner Losh wrote:
: > > I'm busy writing a Ziatech 5503 watchdog driver for FreeBSD (and
: > > porting all the watchdog stuff to DragonFly BSD) and Plan 9. For my
: > > driver, I have no way to identify that the system has the driver, so
: > > I wanted to make it conditional on
: 
: Rather, I have no way to identify that the system has the device :).
: 
: > > options ZT5503
: > 
: > That's not a good enough reason to make it an option, it should really
: > be a device.  Users that want it can add it to their kernel config.
: > In fact, they'd have to add it either way, so why make it weird for
: > them.
: > 
: > Put this device on the ISA bus, give it an identify routine that
: > always adds it (this isn't GENERIC safe, but since there's no way to
: > know the device is there, you are stuck with that).
: 
: OK. I don't know a hell of a lot about how the ISA bus works, though
: I suppose that I remember that things using the old SB 16 cards
: (Wolfenstein, anyone?) would simply probe various I/O ports.

:-)  Yes.  Usually one does try to probe for things, but the devices
must be cooperative.

: Unfortunately, in my case, there are really no board specific I/O
: registers that will give me information I can detect (or so it seems
: from the manufacturer's manuals), though I am going to write a
: couple of tests today to read some of these registers and see if
: there is any useful information contained within them which I
: might use to probe.

Right.  That's too bad, but with somehardware that's what you get.

: Assuming no useful information exists, is it enough to let the
: device attach regardless if the user has
: 
: device zt5503
: 
: in the configuration file? Maxime suggested that I use device hints
: to gather the port and such. Where should I put these hints? NOTES?

/boot/device.hints and also NOTES.

: If I understand correctly, to hook this up into the build, I will
: still have a line in files which will look something like:
: 
: dev/ziatech/zt5503.c	optional zt5503

Yes.
 
: Hm, Ziatech is now Performance Technologies. Should that perhaps be
: dev/pt then instead?

We generally don't have directories for manufacturers.

: Thanks for the help!

No problem.

Warner