From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Brownell Date: Fri, 30 Mar 2001 17:21:08 +0000 Subject: Re: (remove) event not supported. Message-Id: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-hotplug@vger.kernel.org > Mar 30 08:07:01 localhost /etc/hotplug/usb.agent: USB remove event not supported > > What are the issues associated with it. Is this something that just > hasn't been coded up or is it something that can't be coded up. Awkward to code up. What one really wants to happen is have the device's module removed ... and _maybe_ some driver-specific action (not that I can think of any examples just now). But: - the dynamic linking framework doesn't track how many devices are attached to each driver module ... so if there's another device controlled by the same driver, but it's not opened, removing that module would be incorrect. ("module use count" doesn't cover uses, just opens.) - nothing's tracking which modules are used with which device, and if the device is gone you can't query it to find that out! Such issues aren't specific to USB; any hotpluggable bus has such problems. But it's worst for USB: PCMCIA and Cardbus tend to only have one device of a type at a time, and typically only have two slots, but USB can handle a hundred devices, and it's not that uncommon to have multiple devices. > If it simply hasn't been written, if you give me a few pointers on how > it should be written. I'll code it up. I think that it'll be tough to provide a "good" fix for this without updating the module framework; and that maybe a few other issues will show up too. But maybe there are better ways to look at this problem. - Dave _______________________________________________ Linux-hotplug-devel mailing list http://linux-hotplug.sourceforge.net Linux-hotplug-devel@lists.sourceforge.net http://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel