From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oliver Neukum Date: Fri, 09 Feb 2001 17:03:30 +0000 Subject: definition of terms (was: Re: Adding PCMCIA support to the kernel tree -- developers needed.) 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 > > I fear we are being sucked down by semantics. > > You can't get away from that in design discussions. Gotta > eliminate confusions up front. > > And this application structure is very important. You can't > design a "system" without knowing the ways people interact > with it ... /dev/NNN is no more than one part of a 1970s > solution to a simpler system problem than we have today. > We can still use it, but it's not a straightjacket to live in. OK. Let me list all terms used up to now and give a preliminary definition. 'physical device' - hardware, in this context usually hotpluggable 'hotplug event' - any event relating to a hotpluggable device which the kernel may report to user space 'user space agent' - task the kernel spawns in reaction to a hotplug event 'interface driver' - a kernel space driver that user space can use to talk to a physical devices. There may be more than one interface driver per physical device, or in rare cases, none. 'logical driver' - interface the user space agent may set up, which allows the rest of user space to use the services a physical device offers, optional 'device name' - a name userspace uses to identify the interface driver 'stable name' - a device name that depends on a unique characteristic of a device or on the way a device is connected to a bus 'physical location' - a description of how a device is connected to a bus. at one time a connected physical device has one physical location and there is a maximum of one device to a physical location Now to an example: physical device: a USB scanner hotplug event: scanner is plugged in + possibly others (to be decided) user space agent: /sbin/hotplug + scripts called by it interface driver: usbscanner.o logical driver: epson backend of SANE I introduced the term 'interface driver' because it is needed. HTH Oliver _______________________________________________ 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