Hi. We have some USB to CAN devices, and we have the typical problem that the device node (e.g. /dev/pcan0, /dev/pcan1, etc.) is not always the same for the same physical port. I understand that this is expected, but that is solved by inspecting a bit the information that the kernel provides to assign some symbolic link to the wanted one. Or at least that's what I've understood by reading this: http://www.linux-usb.org/FAQ.html#i6 http://comments.gmane.org/gmane.linux.usb.general/61040 http://www.jonnor.com/2010/08/determining-physical-topology-of-hotplugged-usb-devices-with-udev/ But it seems to be failing quite a lot for me, at least on some kernel versions. I was expecting that `udevadm info --query=path` or `lsusb -t` would report exactly the same across reboots if the devices are the same ones, plugged to the same physical ports. Does that make sense? I've tried with different kernels, just in case, and seems only 3.2.0 has the behavior that (maybe naively) I'm expecting (or maybe I didn't tried hard enough). Anyway, I need at least Linux >3.4 since I need to use Bluez 5. My tests: $ md5sum bus*.txt | sort 4a25e1a4ff120110d2447fc2530a22b5 bus-3.12-0.bpo.1-amd64-09-13-19.txt 4a25e1a4ff120110d2447fc2530a22b5 bus-3.12-0.bpo.1-amd64-09-26-57.txt 4a25e1a4ff120110d2447fc2530a22b5 bus-3.9-0.bpo.1-amd64-13-36-30.txt 4a25e1a4ff120110d2447fc2530a22b5 bus-3.9-0.bpo.1-amd64-14-41-29.txt 4b655c3913f0739ce69ca75a2360b3eb bus-3.2.0-4-amd64-08-22-31.txt 4b655c3913f0739ce69ca75a2360b3eb bus-3.2.0-4-amd64-08-25-11.txt 4b655c3913f0739ce69ca75a2360b3eb bus-3.2.0-4-amd64-08-30-16.txt 4b655c3913f0739ce69ca75a2360b3eb bus-3.2.0-4-amd64-14-44-45.txt 4b655c3913f0739ce69ca75a2360b3eb bus-3.2.0-4-amd64-14-45-43.txt 4b655c3913f0739ce69ca75a2360b3eb bus-3.2.0-4-amd64-14-47-22.txt 4b655c3913f0739ce69ca75a2360b3eb bus-3.2.0-4-amd64-14-49-14.txt 545539b21b29af8ca64bcfa5eb1391dc bus-3.9-0.bpo.1-amd64-13-33-37.txt a774c19e12ef21636122d5c573c03393 bus-3.9-0.bpo.1-amd64-13-30-50.txt b26135acc23564e9eee210ecccf5ec6e bus-3.12-0.bpo.1-amd64-09-21-22.txt b26135acc23564e9eee210ecccf5ec6e bus-3.12-0.bpo.1-amd64-09-41-09.txt ce16aca9f56f81101412e1e40f1d141f bus-3.12-0.bpo.1-amd64-09-08-42.txt eeae1db9bffd4016f18f5d4a75279cc6 bus-3.12-0.bpo.1-amd64-09-32-45.txt And contents of the logs I got by running said `udevadm info --query=path` and `lsusb -t`: http://pastie.org/8952893 Any hints are really appreciated. Thank you. -- Alejandro Exojo Piqueras ModpoW, S.L. Technova LaSalle | Sant Joan de la Salle 42 | 08022 Barcelona | www.modpow.es -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
