Georg Acher wrote:
>Hi,
>I'm currently fighting with the timing in hub.c...
>
>The Polestar USB audio device (with the Philips UDA1321) doesn't work anymore
>with the current hub code (it worked a long time ago), the result after a
>plugin is the usual "USB device not accepting new address". This happens
>with both UHCI and OHCI, so it's not a HCD issue.
>
I have seen this with some ov511 cameras. Some particular models need to
have power applied for a second or so before the data pins make contact.
I have a USB power adapter that can do this. Also, reloading the HCD or
disconnecting and reconnecting my hub's upstream cable usually fixes it.
>When inserting a wait_ms(300) in usb_hub_port_reset, it gets detected at the
>second try, with a larger delay is works at the first try. However this long
>delay is not applicable with the current "single-device handling" of hub.c,
>since it would take too long for more than a few connected devices... But
>the long delays are obviously needed for some devices.
>
I seem to recall trying this too. It made it impossible to connect more
than one camera at a time. Even now, I can only connect 3 at most
(probably because I do too much initialization in the probe function).
It seems like even the fastest probe function possible would still not
allow all 127 possible devices per bus. Is there any way to parallelize
the probing?
>[...]
>
> However, the modules are properly detected in Windows 2000, so Linux
>apparently does something wrong.
>
Yeah, I don't have these problems under Win98 or WinME either.
Speaking of hub problems, has anyone else noticed that Linux never
reports overcurrent conditions? I can plug two 500 mA cameras into a
bus-powered hub and no overcurrent condition is reported. The cameras
switch to high power mode and seem to work perfectly. My kernel log says
"hub.c: No over-current condition exists" no matter what. I have
accidentally done this a few times, and I don't know how many more my
hub / host controller can take.
The hub is a D-Link DSB-H4 (VID=0x0441 PID=0x1456). I can provide full
descriptors on request.
--
Mark McClelland
[EMAIL PROTECTED]
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