Re: [RFClue] pci_get_device, new driver model

[Alan Cox <alan@lxorguk.ukuu.org.uk>]

On Gwe, 2005-10-07 at 09:18 -0700, William D Waddington wrote:
> If I convert to pci_get_device, it looks like subsequent calls in the
> loop "put" the previously "gotten" device.  I need the pci_dev struct
> to persist for later use (DMA, etc).  Do I take an additional bump to
> the ref count for each board found before looping, and "put" each when
> the driver is unloaded?

If you are saving the pci device point then yes you should. If you are
using pci_module_init() and the hotplug interface instead then it may
not be neccessary.

> If I just give in to the new driver model how/when do I associate
> instance/minor numbers with boards found?  Is it ever possible for
> ordinary PCI boards to be (logically) removed and re-added w/out
> removing the driver?  If so, how to maintain association between
> a particular board and minor number?

Its up to you how you implement this. One requirement I suspect would be
that the boards have unique serial numbers. Most drivers do not retain
state if someone unplugs a board, moves it and plugs it back in. Instead
they report the old device as "gone" and let user space sort it out