On Thu, 15 Apr 2010, Eric Raymond wrote: > Greg KH <greg@xxxxxxxxx>: > > Use libudev to get this easily. sysfs shows this mapping, look in > > /sys/dev/char/ for the links, or walk backward from the usb device > > itself. > > esr@snark:~/software/gpsd$ lsusb > Bus 001 Device 014: ID 0bb4:0c01 High Tech Computer Corp. > Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub > Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub > Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub > Bus 004 Device 009: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port > Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub > Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub > > The PL2303 is /dev/ttyUSB1, I know because I can read from it. (/dev/ttyUSB0 > is my Googlephone, first line of output.) > > esr@snark:~/software/gpsd$ ls /sys/dev/char/188\:1 > dev device power subsystem uevent > esr@snark:~/software/gpsd$ cat /sys/dev/char/188\:1/dev > 188:1 > esr@snark:~/software/gpsd$ ls /sys/dev/char/188\:1/device > driver port_number power subsystem tty uevent > esr@snark:~/software/gpsd$ ls /sys/dev/char/188\:1/device/tty > ttyUSB1 > > OK, nice to have that confirmation. But I can't find anything > under there that looks like 067b:2303, and even trying to list all the > files hits a symlink loop. > > esr@snark:~/software/gpsd$ cat /sys/dev/char/188\:1/device/port_number > 0 > esr@snark:~/software/gpsd$ cat /sys/dev/char/188\:1/device/uevent > DRIVER=pl2303 > esr@snark:~/software/gpsd$ ls /sys/dev/char/188\:1/device/driver/ttyUSB1 > driver port_number power subsystem tty uevent > esr@snark:~/software/gpsd$ cat /sys/dev/char/188\:1/device/driver/new_id > cat: /sys/dev/char/188:1/device/driver/new_id: Permission denied > esr@snark:~/software/gpsd$ ls -l /sys/dev/char/188\:1/device/driver/new_id > --w------- 1 root root 4096 2010-04-15 09:58 /sys/dev/char/188:1/device/driver/new_id > > Where's the vendor/product ID? You want: cat /sys/dev/char/188\:1/device/../../idVendor cat /sys/dev/char/188\:1/device/../../idProduct Alan Stern -- 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
