Can not connect bus-powered USB hubs?

[Mark]

On Sun, Nov 14, 2004 at 10:18:13PM +0000, James Wilkinson wrote:
James,
I've got it to work! But to be complete I answered your questions anyway...

> USB port <-- ext. cable --><-- ext. cable --><--camera cable--><-- camera -->

It is this last configuration.

> 
> How complex are those cables? How likely is it that there are chips in
> them?

The cables are Eminent EM 1014 booster cables (5 meters long).

> 
> What happens if you take them out of the equation?
The camera works fine when it is connected directly (with it's own cable) to the PC

> 
> > Nov 12 23:32:55 amdrvk kernel: usb 2-2.2: can't connect bus-powered hub to this port
> 
> This message comes from drivers/usb/core/hub.c. Above it is the comment:
>  /* consecutive bus-powered hubs aren't reliable; they can
>   * violate the voltage drop budget.  if the new child has
>   * a "powered" LED, users should notice we didn't enable it
>   * (without reading syslog), even without per-port LEDs
>   * on the parent.
>   */
> 
> The kernel may have become more fussy about proper cabling because the
> alternative may well be lost data.

I installed the kernel sources and looked for the above code. I could not
find it so I decided to build a new kernel. After that the camera worked!!
Only kudzu doesn't work (the PC seems to 'hang') but that is something
I may be able to solve later.

Thanks for pointing me in the right direction and giving me the
last push to go into the 'hassle' of building a kernel.

Mark