DESCRIPTION
The
uhid driver provides support for all HID (Human Interface Device) interfaces in USB devices that do not have a special driver.
Normally the uhid driver is used when no other HID driver attaches to a device. If “flags 1” is specified, the uhid driver will instead attach with a very high priority and always be used. Together with the vendor and product locators on the uhidev(4) driver this can be used to force the uhid driver to be used for a certain device.
The device handles the following ioctl(2) calls:
-
USB_GET_REPORT_ID (int)
-
Get the report identifier used by this HID report.
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USB_GET_REPORT_DESC (struct usb_ctl_report_desc)
-
Get the HID report descriptor. 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_ctl_report_desc {
int ucrd_size;
u_char ucrd_data[1024]; /* filled data size will vary */
};
-
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.
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USB_GET_REPORT (struct usb_ctl_report)
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Get a report from the device without waiting for data on the interrupt pipe. The report 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.
struct usb_ctl_report {
int ucr_report;
u_char ucr_data[1024]; /* used data size will vary */
};
-
USB_SET_REPORT (struct usb_ctl_report)
-
Set a report in the device. The report field indicates which report is to be set. 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_GET_DEVICEINFO (struct usb_device_info)
-
Get an information summary for the device. This call will not issue any USB transactions.
-
USB_GET_STRING_DESC (struct usb_string_desc)
-
Get a string descriptor for the given language id and string index.
struct usb_string_desc {
int usd_string_index;
int usd_language_id;
usb_string_descriptor_t usd_desc;
};
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) send data to the device. Data should be written in chunks of the size prescribed by the report descriptor.