Hi, sorry for the wrong patch format. I am trying to detect a change. At the moment I think the change could be ignored if a port connection-change occurs and the port status has again the 'PORT_CONNECTION' bit set. I have a fx3 device which does a re-enumeration after a firmware download. This is working as expected and I am seeing a 'remove event' and a 'add event' monitoring via udevadm. But if I connect multiple devices at the same time via an usb hub I am sometimes not receiving a 'remove event' and 'add event' for a single device. I think the problem could be that when a device disconnects and the port connection-change occurs and before the 'PORT_CONNECTION' bit is checked the device could already be reconnected and the 'PORT_CONNECTION' bit is set. Therefore I think it is not correct to resuscitate the exisiting device. On Fri, Sep 20, 2019 at 10:55:56AM +0200, Greg KH wrote: > On Fri, Sep 20, 2019 at 12:36:28PM +0200, David Heinzelmann wrote: > > When a port connection-change occurs the hub driver tries to resuscitate an existing device. > > Activated from a firmware download a usb device can re-enumerate with new or changed device > > descriptors. Therefore it will be checked for changed device descriptors before the connection > > is resuscitated and the connection-change event is ignored. > > Please wrap your lines at 72 columns :( > > Anyway, what problem are you trying to solve here? What is broken with > how things work today? Are you trying to ignore a change that is > currently showing up as a change, or trying to do the opposite? > > thanks, > > greg k-h
