Re: Suspend/resume semantics for ISDN drivers (was: NAK new drivers without proper power management?)

On Saturday, 3 March 2007 23:48, Tilman Schmidt wrote:
Ok, I've thought some more but I still don't know ...

On 12.02.2007 01:10 I wrote:
I don't doubt your basic assessment. However it doesn't translate that
easily into a real implementation. In my case, I maintain a USB driver,
so I have to deal with USB specifics of suspend/resume which happen not
to be that well documented. My driver provides an isdn4linux device but
isdn4linux knows nothing about suspend/resume so I am on my own on how
to reconcile the two. The device itself, though in turn far from trivial,
is actually the least of my worries.

So, how *should* an isdn4linux driver handle a request to suspend?
Specifically, if there are active connections, should it try to
shut them down in an orderly fashion (which might imply some delays
waiting for the remote station to acknowledge, etc.)? Should it kill
them abruptly (as for a USB unplug event)? Or should it just refuse
to suspend while a connection is still active?

I think that refusing to suspend wouldn't be a good approach (think of an
emergency suspend when the battery is running low).

Probably the closing of connections would be the nicest thing from the
user's point of view.

Greetings,
Rafael
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