Re: introduce device_is_attached()

[Christoph Egger <Christoph_Egger%gmx.de@localhost>]

On 16.04.12 19:12, Matt Thomas wrote:
> 
> On Apr 16, 2012, at 9:52 AM, Christoph Egger wrote:
> 
>>
>> Hi,
>>
>> I want to introduce a new function to sys/devices.h:
>>
>> bool device_is_attached(device_t parent, cfdata_t cf);
> 
> I'd prefer device_is_attached_p

Ok, I will rename it.

>> The purpose is for bus drivers who wants to attach children
>> and ensure that only one instance of it will attach.
>>
>> 'parent' is the bus driver and 'cf' is the child device
>> as passed to the submatch callback via config_search_loc().
>>
>> The return value is true if the child is already attached.
> 
> Can it be used in driver match routines so they don't need to
> keep a local to prevent multiple matches?

Oh, good point. I think this is possible and will make
struct amdnb_misc_softc completely superflous.
I will give this a try tomorrow.

Christoph