On Fri, 11 Mar 2005, abcd efgh wrote: > Hello, > > Recently we moved to FC3 (2.6.10) from RH9 (2.4.23). I have a board with a > USB hub (Philips ISP1521 BE) with some chips behind it. In 2.6.10, USB > driver doesn't recognize the chips behind the controller. But, the same > board works fine with 2.4.23. > > I went into the driver, and came to know that this hub was returning (1011 > 0010) as wHubCharacteristics, and pPwrOn2PwrGood as 0. This hub is a powered > hub (doesn't draw power from bus), and high speed. I only use all high > speed, so I guess TT's do not come into picture.
Lack of power switching implies that the hub follows the USB 1.0 standard, but since it is high speed it actually follows the USB 2.0 standard. Also, overcurrent protection may be omitted only for bus-powered hubs. Clearly the value is wrong. > The driver used to recognize only the hub - nothing else behind it. So, I > changed the wHubCharacteristics with a proper value whenever I found this > device (for a temporary fix). Now, I can see behind this hub. Do you mean that after your changes, the 2.6.10 USB core is able to detect devices plugged into the hub? What change did you make to wHubCharacteristics? > But, I am getting a few (very infrequent) "port x disabled by hub (EMI?), > re-enabling.." messages. I didn't get much information in the code/specs > about the reason. That message is printed whenever a hub disables one of its ports all by itself. This can happen because of electromagnetic interference, or a bad cable or connector, or because the device plugged into the port is malfunctioning, or because the hub itself is malfunctioning. Alan Stern ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click _______________________________________________ Linux-usb-users@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-users
