UHID(4)                FreeBSD Kernel Interfaces Manual                UHID(4)

NAME
     uhid - USB generic HID support

SYNOPSIS
     To compile this driver into the kernel, place the following line in your
     kernel configuration file:

           device uhid
           device hid
           device usb

     Alternatively, to load the driver as a module at boot time, place the
     following line in loader.conf(5):

           uhid_load="YES"

DESCRIPTION
     The uhid driver provides support for all HID (Human Interface Device)
     interfaces in USB devices that do not have a special driver.

     The device handles the following ioctl(2) calls:

     USB_GET_REPORT_ID (int)
             Get the report identifier used by this HID report.

     USB_GET_REPORT_DESC (struct usb_gen_descriptor)
             Get the HID report descriptor.  Copies a maximum of ugd_maxlen
             bytes of the report descriptor data into the memory specified by
             ugd_data.  Upon return ugd_actlen is set to the number of bytes
             copied.  Using this descriptor the exact layout and meaning of
             data to/from the device can be found.  The report descriptor is
             delivered without any processing.

             struct usb_gen_descriptor {
                     void   *ugd_data;
                     uint16_t ugd_maxlen;
                     uint16_t ugd_actlen;
                     uint8_t ugd_report_type;
                     ...
             };

     USB_SET_IMMED (int)
             Sets the device in a mode where each read(2) will return the
             current value of the input report.  Normally a read(2) will only
             return the data that the device reports on its interrupt pipe.
             This call may fail if the device does not support this feature.

     USB_GET_REPORT (struct usb_gen_descriptor)
             Get a report from the device without waiting for data on the
             interrupt pipe.  Copies a maximum of ugd_maxlen bytes of the
             report data into the memory specified by ugd_data.  Upon return
             ugd_actlen is set to the number of bytes copied.  The
             ugd_report_type field indicates which report is requested.  It
             should be UHID_INPUT_REPORT, UHID_OUTPUT_REPORT, or
             UHID_FEATURE_REPORT.  This call may fail if the device does not
             support this feature.

     USB_SET_REPORT (struct usb_gen_descriptor)
             Set a report in the device.  The ugd_report_type field indicates
             which report is to be set.  It should be UHID_INPUT_REPORT,
             UHID_OUTPUT_REPORT, or UHID_FEATURE_REPORT.  The value of the
             report is specified by the ugd_data and the ugd_maxlen fields.
             This call may fail if the device does not support this feature.

     USB_GET_DEVICEINFO (struct usb_device_info)
             Returns information about the device, like USB vendor ID and USB
             product ID.  This call will not issue any USB transactions.  Also
             refer to ugen(4).

     Use read(2) to get data from the device.  Data should be read in chunks
     of the size prescribed by the report descriptor.

     Use write(2) to send data to the device.  Data should be written in
     chunks of the size prescribed by the report descriptor.

SYSCTL VARIABLES
     The following variables are available as both sysctl(8) variables and
     loader(8) tunables:

     hw.usb.uhid.debug
             Debug output level, where 0 is debugging disabled and larger
             values increase debug message verbosity.  Default is 0.

FILES
     /dev/uhid?

SEE ALSO
     usbhidctl(1), usb(4)

HISTORY
     The uhid driver appeared in NetBSD 1.4.  This manual page was adopted
     from NetBSD by Tom Rhodes <trhodes@FreeBSD.org> in April 2002.

FreeBSD 13.1-RELEASE-p6        October 31, 2020        FreeBSD 13.1-RELEASE-p6