On Sat, Jan 3, 2009 at 11:19, Marcel Holtmann <marcel@xxxxxxxxxxxx> wrote: >> >>> >> > I was playing a little bit with libudev and I actually need the DEVTYPE >> >>> >> > from uevent for various tasks. Especially with USB and Bluetooth, the >> >>> >> > subsystem value is too generic. >> >>> >> > >> >>> >> > Attached is a patch that implements udev_device_get_devtype() and also >> >>> >> > udev_device_get_parent_with_devtype(). Please double check that I did it >> >>> >> > the right way. >> >>> >> >> >>> >> Looks good. Applied. >> >>> > >> >>> > one minor thing that came to my mind is that DEVTYPE and subsystem are >> >>> > actually kinda coupled. So a DEVTYPE="host" has a different semantic for >> >>> > USB than for Bluetooth subsystem for example. Not sure if we actually >> >>> > care or just add a udev_device_get_parent_with_subsystem_devtype() >> >>> > function to give applications a choice if they wanna care. >> >>> >> >>> You mean replacing: >> >>> udev_device_get_parent_with_devtype(..., *devtype) >> >>> by: >> >>> udev_device_get_parent_with_subsystem_devtype(..., *subsystem, *devtype) >> >>> ? >> >>> >> >>> Sounds sensible, because in most cases you don't want to check for >> >>> parents of a different subsystem. As you are using it, want to send a >> >>> patch? >> >> >> >> I am thinking of keeping both. So just adding ...subsystem_devtype() and >> >> keeping also the original one. My reason for it is that in some case you >> >> already know the subsystem you are looking at (or don't care in). So no >> >> point in doing a lookup with two checks. >> > >> > We could make it accept NULL for the subsystem in that case? >> >> I guess, we should just have >> udev_device_get_parent_with_subsystem_devtype(), and drop the both >> other ones, and accept NULL as parameters, if you want to match only >> one. You are right that subsystem and devtype belong together, so we >> should probably reflect that in the API. Any problems with such >> change? > > I think that make sense. So I opted for allowing devtype being NULL > while subsystem is required. I tried to come up with a good reason why > you would look for devtype and not subsystem and couldn't find it right > now. The USB case is double information since they prefixed their > devtypes with "usb_", but that is really an USB subsystem problem. For > Bluetooth I am not doing this at all and neither does SCSI. In future no > subsystem should. Yeah, sounds all fine. Patches are applied. Thanks a lot, Kay -- To unsubscribe from this list: send the line "unsubscribe linux-hotplug" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
