On 11/3/2004 17:57, Alan Stern wrote:
For any driver, there's a limit to how much device bugginess it can copeI modified the speedtch driver to timeout UBRs after a specified time but this has not solved the problem. Well, at least the connection didn't freeze but I was still unable to download certain files. The UBRs got restarted but the same time the bug kicked in again and the URB has never been completed.
with. This PIIX3 bug exceeds the limit of the UHCI driver as it now
stands. Maybe some time in the future the prospect will improve. For
now, the modem driver can be made to cope with the problem by timing out
URBs and resubmitting them. I realize this is awkward, but it's the best
I can offer...
So I decided to focus on lower layers. I modified uhci driver to detect the frozen state and correct it if it persists for some time. I doubt that it correctly detect and fix only the frozen states but with this modification everything seems to work fine. I'll post the patch for driver when I'll do more extensive testing. If there's someone with similar problem, he/she can try if it helps.
But ... All this have a minor glitch. When I was downloading at higher speeds I noticed that one LED on my modem occasionally blinks red. The user manual says it means "USB congestion". At also says it may be occur when there are more devices connected to the bus (not my case, modem is a single USB device I use). In logs I discovered that speedtch driver is complaining about bogus data received. I guess it may be the result of mentioned congestion. At first I thought I messed something up in uhci driver but congestion (or whatever it is) showed up also with the original one. I tried three different versions of uhci driver (from 2.6.8.1, 2.6.9 and 2.6.10-rc1). On the other hand, the problem is not present in 2.4.27. I don't know how much the driver changed between 2.4 and 2.6 branches and if the changes could cause this behavior. This could be an issue of the kernel itself as well.
I don't know exactly what USB congestion is. I can only guess that computer is not fast enough in receiving data from modem and thus the USB get congested. But this is just a wild guess. Any more suggestions where the problem could be? Does anyone ever encountered the "USB congestion" ?
Best regards,
Andrej Kristofic
------------------------------------------------------- This SF.Net email is sponsored by: InterSystems CACHE FREE OODBMS DOWNLOAD - A multidimensional database that combines robust object and relational technologies, making it a perfect match for Java, C++,COM, XML, ODBC and JDBC. www.intersystems.com/match8 _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-users
