Hi Alan, Thanks for your reply.
On Wed, Mar 16, 2005 at 10:17:13PM -0500, Alan Stern wrote: > > I have to wonder why they did that? How do they think people can use > sysfs instead of /proc/bus/usb/devices? There's lots of information in > /proc/bus/usb/devices that isn't in sysfs at all. I am wondering about the same thing. > > > > Of course, that breaks the VMWare and I add some option > > > to use this wired file name. > > > > > > I am wondering how to get the devices change event from > > > sysfs in the user space if VMware want to use sysfs instead? > > Device change events have nothing to do with either sysfs or > /proc/bus/usb/devices. Use hotplug. Right now VMware select() on the /proc/bus/usb/devices for the device change event arrived. Maybe this topic belong to the hotplug mailing list. > > Short of rmmod'ing a driver, there is no way to prevent the kernel from > binding it to a device. However, VMware can tell the kernel to _unbind_ a > driver by using the USBDEVFS_DISCONNECT ioctl in usbfs. I add the USBDEVFS_DISCONNECT to VMware recently. But that doesn't solved all the problems. Let the device bind to a kernel driver then disconnect it again will disturb some (broken) USB devices. Some PDA syncing tend to have this problem. I guess the firmware in the PDA has some pretty straight forward initialing sequence in mind, anything beyond that is likely goto an untested code path. In that case, it would be best not to let the kernel driver touch the device at all. I am thinking an option that kernel will aways pass the event to hotplug and let the hotplug decide what to do next. > > It might be possible to change the hotplug manager so that VMware could > tell it to ignore USB events. I will look into that. As I mention above, the kernel needs the ability to the skip the binding in the first place. Thanks again. Chris ------------------------------------------------------- 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-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
