Am Thu, 22 Jan 2009 00:20:00 +0100 schrieb Laurent Pinchart <laurent.pinchart@xxxxxxxxx>: > Hi Carsten, > > On Wednesday 21 January 2009, Carsten Meier wrote: > > > > now I want to translate bus_info into a sysfs-path to obtain > > device-info like serial numbers. Given a device reports > > "usb-0000:00:1d.2-2" as bus_info, then the device-info is located > > under "/sys/bus/usb/devices/2-2", which is a symlink to the > > appropriate /sys/devices/ directory, right? > > I'm afraid not. In the above bus_info value, 0000:00:1d.2 is the PCI > bus path of your USB controller, and the last digit after the dash is > the USB device path. > > > All I have to do is to compare the first 4 chars of bus_info against > > "usb-", get the chars after "." and append it to > > "/sys/bus/usb/devices/" to obatin a sysfs-path, right? > > > > Is there a more elegant solution or already a function for this? Can > > the "." appear more than once before the last one? > > Probably not before, but definitely after. > > Root hubs get a USB device path set to '0'. Every other device is > numbered according to the hub port number it is connected to. If you > have an external hub connected on port 2 of your root hub, and have a > webcam connected to port 3 of the external hub, usb_make_path() will > return "usb-0000:00:1d.2-2.3". > > Cheers, > > Laurent Pinchart Hi, On my machine, my pvrusb2 (connected directly to my mini-pc) shows up under "/sys/bus/usb/devices/7-2/" which is a symbolic link to "../../../devices/pci0000:00/0000:00:1d.7/usb7/7-2" I can't test for the new bus_info-string, because it's not fixed yet in the driver. But if I got it correctly it should be "usb-0000:00:1d.7-7.2" ? Then I've to simply take the string after the last dash, replace "." by "-" and append it to "/sys/bus/usb/devices/" for a sysfs-path? Regards, Carsten -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
