On Tue, 4 May 2004 [EMAIL PROTECTED] wrote: > >This is odd. It says the USB controller in your computer is not aware > >that anything has been plugged in. It's just as though no electrical > >connection was made. In particular, look at the stat1 = 0080 line. The > >least significant bit of that value is the Current Connection Status > >indicator; the fact that it is 0 means the controller is unaware that > >anything is attached to the port. > > Now is it truely the controller that didn't detect the plugin, or > that it didn't report the plugin via an interrupt to driver sw that > eventually updates this info?
The contents of the /proc file are taken directly from registers on the controller itself. The values indicate that the controller didn't detect the plugin (and consequently, of course, didn't report anything either). > >Three possibilities: your USB controller is bad, your cable is bad, or > >your USB device is bad. Since the same thing happens with multiple > >devices (and also multiple cables?) we can rule out the last possibility > >(and the second as well?). This makes me think the USB hardware on your > >computer may be faulty. > > Yup, thats why I went back and tried it 15 thousand more times, just to > prove I wasn't going insane. I believe you. Well, not the 15,000 part. :-) > >However, you say that everything works okay under Linux 2.4. Have you > >tried it recently? > > Just tried it, and it _still_ works find with 2.4. > > It looks as if something has programmed the USB controller to ignore the > 'leaving' status change. Does the coldplug detect also go through > an status change detect phase, or does it poll for devices uppon the > driver's first activation. ie. I have had all 3 devices plugged in > before powerup. Then one at a time, I've unplugged them, and each one > in turn dissappears. But once gone, they can never come back. Kind of > like inserts are ignored, but removals are detected. Thats why I ask > 'how are devices detected at powerup? asynchronously, or polled in init > ()?' The UHCI driver always detects devices the same way, by querying the hardware, regardless of the time. There's no difference between connection detection for coldplug and hotplug. However, the fact that things behave differently at boot time suggests that the BIOS may be involved somehow. If you've got a Legacy USB Support entry in your BIOS configuration, try making sure that it's turned off. Other people have had similar problems cured by doing that. Alan Stern ------------------------------------------------------- This SF.Net email is sponsored by: Oracle 10g Get certified on the hottest thing ever to hit the market... Oracle 10g. Take an Oracle 10g class now, and we'll give you the exam FREE. http://ads.osdn.com/?ad_id=3149&alloc_id=8166&op=click _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
