[libhid-discuss] Find the path...

Matthias Lohr malo at dasevil.de
Thu Dec 6 19:44:32 UTC 2007


matthias at scripterhome:~$ sudo libhid-detach-device 04b4:0f1f
Trying to detach HID with IDs 04b4:0f1f... done.
matthias at scripterhome:~$ sudo lsusb -d 04b4:0f1f -vvv
matthias at scripterhome:~$ sudo lsusb -d 04b4:0f1f -vvv

Bus 001 Device 005: ID 04b4:0f1f Cypress Semiconductor Corp.
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               1.10
  bDeviceClass            0 (Defined at Interface level)
  bDeviceSubClass         0
  bDeviceProtocol         0
  bMaxPacketSize0         8
  idVendor           0x04b4 Cypress Semiconductor Corp.
  idProduct          0x0f1f
  bcdDevice            1.10
  iManufacturer           1 Digital Enlightenment
  iProduct                2 Sunlight Killer
  iSerial                 3 0000000000000532
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength           41
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0
    bmAttributes         0x80
      (Bus Powered)
    MaxPower              200mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           2
      bInterfaceClass         3 Human Interface Devices
      bInterfaceSubClass      0 No Subclass
      bInterfaceProtocol      0 None
      iInterface              0
        HID Device Descriptor:
          bLength                 9
          bDescriptorType        33
          bcdHID               1.10
          bCountryCode            0 Not supported
          bNumDescriptors         1
          bDescriptorType        34 Report
          wDescriptorLength      36
         Report Descriptors:
           ** UNAVAILABLE **
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0021  1x 33 bytes
        bInterval               1
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x02  EP 2 OUT
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0021  1x 33 bytes
        bInterval               1
Device Status:     0x0000
  (Bus Powered)
matthias at scripterhome:~$

Look at the beginning. I have to exec lsusb two times, before i get some 
output! after the first lsusb, the usbhid driver is loaded for this device!

Greetings
Matthias Lohr

On Wednesday 05 December 2007 14:39:59 Charles Lepple wrote:
> That doesn't sound right. If you re-plug the device, the kernel
> usbhid driver will claim it again, but running test_libhid (or libhid-
> detach-device, also included in libhid) should make lsusb show the
> descriptor.
>
> Are there any errors in dmesg?
>
> Do you have read+write permissions to the device node (in /proc/bus/
> usb or /dev/bus/usb)?
>
> What does "cat /proc/bus/usb/devices" say?
>
> On Dec 5, 2007, at 1:28 AM, Matthias Lohr wrote:
> > Doesn't work. lsusb seems to reload the usb driver...
> >
> > Matthias
> >
> > On Wednesday 05 December 2007 01:44:57 Charles Lepple wrote:
> >> On Dec 4, 2007, at 7:28 PM, Peter Stuge wrote:
> >>> On Tue, Dec 04, 2007 at 08:47:11PM +0100, Matthias Lohr wrote:
> >>>> // lsusb
> >>>>     Report Descriptors:
> >>>>       ** UNAVAILABLE **
> >>>
> >>> Disable the HID driver to make it available.
> >>>
> >>> Either unload the driver or write a small program to call
> >>> usb_detach_driver_np() in libusb, or the equivalent in libhid.
> >>
> >> Matthias,
> >>
> >> Peter is right, but by running the test program, you detached the
> >> driver. Try running lsusb again.
> >
> > _______________________________________________
> > libhid-discuss mailing list
> > libhid-discuss at lists.alioth.debian.org
> > http://lists.alioth.debian.org/mailman/listinfo/libhid-discuss
>
> _______________________________________________
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> libhid-discuss at lists.alioth.debian.org
> http://lists.alioth.debian.org/mailman/listinfo/libhid-discuss




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