Subject: Re: another question about bus_space_map
To: None <tech-kern@NetBSD.ORG>
From: Michael Richardson <mcr@sandelman.ottawa.on.ca>
List: tech-kern
Date: 02/05/1997 09:13:54
>>>>> "Chris" == Chris G Demetriou <cgd@CS.cmu.edu> writes:
>> I take it that the probe routines should call bus_space_unmap
>> on allocated things if they fail to find a card? What is an
>> invalid value for bus_space_handle_t? 0? ~0?
Chris> there are no defined valid or invalid values. the only
Chris> indication of 'validity' is the return value from
Chris> bus_space_map().
The desire is to have a cleanup section that reads:
notfound:
if(some_alloc_handle) bus_space_unmap(iot,some_alloc_handle,...);
if(some_other_handle) bus_space_unmap(iot,some_other_handle,...);
>> Should a probe routine unmap everything and let the attach
>> routine map it back in?
Chris> yes. there should be no permanent allocations or
Chris> initializations done in the match/probe routine, EVER.
Thank you for this info. I'd like to know how Perry's 'section 9' of
the manual is going, and whether I can provide some input as I pick
the details up. Maybe having man pages written by someone learning the
particulars would be better than a gospel?
:!mcr!: | Network security consulting and
Michael Richardson | contract programming
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