James Carlson wrote:
> Lei Chen writes:
>   
>> James Carlson wrote:
>>     
>>> Is this something separate from devfsadmd?  Should it be?
>>>   
>>>       
>> In fact, this daemon is used to handle wireless USB device connection 
>> context, while the devfsadmd manages reconfiguration and device dynamic 
>> events. The new daemon needs to interact with  WUSB host to setup a 
>> wireless USB device's connection context. The interactions between 
>> daemon and host are through ioctl.
>>     
>
> Is this different from regular USB?  How so?  I suspect I'm missing
> some background.
>   
Yes, wireless USB is a new technology which defines a protocol for 
providing short-range, high-bandwidth wireless radio communication. The 
wireless nature presents the first significant difference for a wusb 
device from a wired one. That is, by some means defined by WUSB, 
wireless host and device must first establish a secure relationship 
before they can connect to each other. They have to set up a connection 
context. The wikipage http://en.wikipedia.org/wiki/Wireless_USB has a 
brief introduction and links.

I will find out who is in charge of device driver now.

Thanks,
Lei Chen

> I would have expected that, as part of managing the relationship
> between the wireless USB device and the system, devfsadmd would need
> to interact with the wireless subsystem and create/destroy nodes on
> the fly, just as it does for all other dynamic subsystems.
>   
> Have you talked this over with the device driver folks?  (Not sure who
> they are since Shudong left ... but they have to exist somewhere.)
>   
>   
>>> In fact, the device node doesn't even have to exist at all for
>>> ioctl(2) to work correctly, and I see nothing that requires write
>>> permissions in order to do ioctls.
>>>
>>> Am I missing something?  Have you tried this and failed?
>>>   
>>>       
>> Thank you for the reminding. I had taken it for granted that ioctl needs 
>> write permission. Yes, as long as the user can open the device even only 
>> with O_RDONLY mode, the ioclt can also be done on it. This might be an 
>> issue for a wireless USB host device. The drv_priv(9F) should be used to 
>> check application's privilege to prevent any user with only read 
>> permissions from stopping a host device.
>>     
>
> Yes; that seems reasonable.  (Assuming that the device node
> permissions are correct.)
>
>   


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