[pvrusb2] How to uniquely identify a device

[Mike Isely]

On Sun, 11 Jan 2009, Carsten Meier wrote:

> 
> OK, I try to make my point of view a little bit clearer by describing
> a use-case. How to associate config-data (e.g. control-settings) with
> a video-device? Two possible approaches:
> 
> 1. Save device-file-name with the config data (e.g. /dev/video1).
> This won't work reliably because device-nodes are created dynamicly
> 
> 2. Save card and bus_info with config data. This is what bus_info was
> intended for with statical PCI-cards without serial-numbers in mind.
> (Here the reported bus_info is always the same)
> 
> The second approach is not possible with the current
> pvrusb2's implementation for reporting bus_info. It literally follows
> the struct-member name and returns the USB-bus-info, but doesn't
> consider its primary intention.
> 
> I hope I could make it clear, it's hard for me to explain things in
> english. Thanks for re-evaluation. :)

You don't have to convince me of the use-case.  I understand that 
perfectly well and agree with the need.  I just want to review the V4L 
spec and look at a few other driver examples before committing to a 
change like that.  I also want to be sure we're not missing another 
(easy) way to do this.

  -Mike

-- 

Mike Isely
isely @ pobox (dot) com
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