USB: HID Report Descriptor

On Windows and MacOS

See this page.

https://github.com/tmk/tmk_keyboard/wiki/USB-Descriptor

On Linux

lsusb on Linux

http://www.slashdev.ca/2010/05/08/get-usb-report-descriptor-with-linux/

Find vendor id of device interested(046d)

$ lsusb
...
Bus 002 Device 007: ID 046d:c01d Logitech, Inc. MX510 Optical Mouse
...

Find device path from dmesg output(2-2.4:1.0)

$ dmesg | grep -i 046d | grep devices | tail -5
Aug 12 09:15:55 desk kernel: [166377.779960] input: Logitech USB-PS/2 Optical Mouse as /devices/pci0000:00/0000:00:04.1/usb2/2-2/2-2.4/2-2.4:1.0/0003:046D:C01D.0067/input/input106

Unbind the device and it stops working

$ echo -n 2-2.4:1.0 | sudo tee /sys/bus/usb/drivers/usbhid/unbind

Dump report descriptor with lsusb

$ sudo lsusb -d046d: -v
...
  iInterface              0
    HID Device Descriptor:
      bLength                 9
      bDescriptorType        33
      bcdHID               1.10
      bCountryCode            0 Not supported
      bNumDescriptors         1
      bDescriptorType        34 Report
      wDescriptorLength      77
      Report Descriptor: (length is 77)
        Item(Global): Usage Page, data= [ 0x01 ] 1
                        Generic Desktop Controls
        Item(Local ): Usage, data= [ 0x02 ] 2
                        Mouse
        Item(Main  ): Collection, data= [ 0x01 ] 1
                        Application
        Item(Local ): Usage, data= [ 0x01 ] 1
                        Pointer
        Item(Main  ): Collection, data= [ 0x00 ] 0
                        Physical
        Item(Global): Usage Page, data= [ 0x09 ] 9
                        Buttons
...

Bind the deivce and it starts working again

$ echo -n 2-2.4:1.0 | sudo tee /sys/bus/usb/drivers/usbhid/bind

usbhid-dump on Linux

Dump descriptor and parse it like this.

$ sudo usbhid-dump -d046d -i255
001:005:000:DESCRIPTOR         1468982571.405056
 05 01 09 02 A1 01 09 01 A1 00 05 09 19 01 29 08
 15 00 25 01 95 08 75 01 81 02 95 00 81 03 06 00
 FF 09 40 95 02 75 08 15 81 25 7F 81 02 05 01 09
 38 15 81 25 7F 75 08 95 01 81 06 09 30 09 31 16
 01 F8 26 FF 07 75 0C 95 02 81 06 C0 C0          
         
$ sudo usbhid-dump -d046d -i255 |grep -v : | xxd -r -p | hidrd-convert -o spec
Usage Page (Desktop),               ; Generic desktop controls (01h)
Usage (Mouse),                      ; Mouse (02h, application collection)
Collection (Application),
    Usage (Pointer),                ; Pointer (01h, physical collection)
    Collection (Physical),
        Usage Page (Button),        ; Button (09h)
        Usage Minimum (01h),
        Usage Maximum (08h),
        Logical Minimum (0),
        Logical Maximum (1),
        Report Count (8),
        Report Size (1),
        Input (Variable),
        Report Count (0),
        Input (Constant, Variable),
        Usage Page (FF00h),         ; FF00h, vendor-defined
        Usage (40h),
        Report Count (2),
...

How to build

$ git clone https://github.com/DIGImend/hidrd.git
$ git clone https://github.com/DIGImend/usbhid-dump.git
$ cd hidrd # or usbhid-dump
$ autoreconf --force --install
$ ./configure
$ make

Descriptors Examples

Logitech MX510 mouse

$ sudo usbhid-dump -d 046d -i255 | grep -v : | xxd -r -p | hidrd-convert -o spec
Usage Page (Desktop),               ; Generic desktop controls (01h)
Usage (Mouse),                      ; Mouse (02h, application collection)
Collection (Application),
    Usage (Pointer),                ; Pointer (01h, physical collection)
    Collection (Physical),
        Usage Page (Button),        ; Button (09h)
        Usage Minimum (01h),
        Usage Maximum (08h),
        Logical Minimum (0),
        Logical Maximum (1),
        Report Count (8),
        Report Size (1),
        Input (Variable),
        Report Count (0),
        Input (Constant, Variable),
        Usage Page (FF00h),         ; FF00h, vendor-defined
        Usage (40h),
        Report Count (2),
        Report Size (8),
        Logical Minimum (-127),
        Logical Maximum (127),
        Input (Variable),
        Usage Page (Desktop),       ; Generic desktop controls (01h)
        Usage (Wheel),              ; Wheel (38h, dynamic value)
        Logical Minimum (-127),
        Logical Maximum (127),
        Report Size (8),
        Report Count (1),
        Input (Variable, Relative),
        Usage (X),                  ; X (30h, dynamic value)
        Usage (Y),                  ; Y (31h, dynamic value)
        Logical Minimum (-2047),
        Logical Maximum (2047),
        Report Size (12),
        Report Count (2),
        Input (Variable, Relative),
    End Collection,
End Collection