1.\" $NetBSD: ugen.4,v 1.13 2001/09/11 22:52:54 wiz Exp $ 2.\" 3.\" Copyright (c) 1999 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to The NetBSD Foundation 7.\" by Lennart Augustsson. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 3. All advertising materials mentioning features or use of this software 18.\" must display the following acknowledgement: 19.\" This product includes software developed by the NetBSD 20.\" Foundation, Inc. and its contributors. 21.\" 4. Neither the name of The NetBSD Foundation nor the names of its 22.\" contributors may be used to endorse or promote products derived 23.\" from this software without specific prior written permission. 24.\" 25.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 26.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 29.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35.\" POSSIBILITY OF SUCH DAMAGE. 36.\" 37.\" $FreeBSD$ 38.\" 39.Dd November 22, 2006 40.Dt UGEN 4 41.Os 42.Sh NAME 43.Nm ugen 44.Nd USB generic device support 45.Sh SYNOPSIS 46To compile this driver into the kernel, 47place the following line in your 48kernel configuration file: 49.Bd -ragged -offset indent 50.Cd "device ugen" 51.Ed 52.Pp 53Alternatively, to load the driver as a 54module at boot time, place the following line in 55.Xr loader.conf 5 : 56.Bd -literal -offset indent 57ugen_load="YES" 58.Ed 59.Sh DESCRIPTION 60The 61.Nm 62driver provides support for all USB devices that do not have 63a special driver. 64It supports access to all parts of the device, 65but not in a way that is as convenient as a special purpose driver. 66.Pp 67There can be up to 127 USB devices connected to a USB bus. 68Each USB device can have up to 16 endpoints. 69Each of these endpoints 70will communicate in one of four different modes: control, isochronous, 71bulk, or interrupt. 72Each of the endpoints will have a different 73device node. 74The four least significant bits in the minor device 75number determines which endpoint the device accesses and the rest 76of the bits determines which USB device. 77.Pp 78If an endpoint address is used both for input and output the device 79can be opened for both read or write. 80.Pp 81To find out what endpoints that exist there are a series of 82.Xr ioctl 2 83operation on the control endpoint that returns the USB descriptors 84of the device, configurations, interfaces, and endpoints. 85.Pp 86The control transfer mode can only happen on the control endpoint 87which is always endpoint 0. 88The control endpoint accepts request 89and may respond with an answer to such request. 90Control request 91are issued by 92.Xr ioctl 2 93calls. 94.\" .Pp 95.\" The isochronous transfer mode can be in or out depending on the 96.\" endpoint. 97.\" To perform I/O on an isochronous endpoint 98.\" .Xr read 2 99.\" and 100.\" .Xr write 2 101.\" should be used. 102.\" Before any I/O operations can take place the transfer rate in 103.\" bytes/second has to be set. 104.\" This is done with 105.\" .Xr ioctl 2 106.\" .Dv USB_SET_ISO_RATE . 107.\" Performing this call sets up a buffer corresponding to 108.\" about 1 second of data. 109.Pp 110The bulk transfer mode can be in or out depending on the 111endpoint. 112To perform I/O on a bulk endpoint 113.Xr read 2 114and 115.Xr write 2 116should be used. 117All I/O operations on a bulk endpoint are unbuffered. 118.Pp 119The interrupt transfer mode can be in or out depending on the 120endpoint. 121To perform I/O on an interrupt endpoint 122.Xr read 2 123and 124.Xr write 2 125should be used. 126A moderate amount of buffering is done 127by the driver. 128.Pp 129All endpoints handle the following 130.Xr ioctl 2 131calls: 132.Bl -tag -width indent 133.It Dv USB_SET_SHORT_XFER Pq Vt int 134Allow short read transfer. 135Normally a transfer from the device 136which is shorter than the request specified is reported as an 137error. 138.It Dv USB_SET_TIMEOUT Pq Vt int 139Set the timeout on the device operations, the time is specified 140in milliseconds. 141The value 0 is used to indicate that there is 142no timeout. 143.El 144.Pp 145The control endpoint (endpoint 0) handles the following 146.Xr ioctl 2 147calls: 148.Bl -tag -width indent 149.It Dv USB_GET_CONFIG Pq Vt int 150Get the device configuration number. 151.It Dv USB_SET_CONFIG Pq Vt int 152Set the device into the given configuration number. 153.Pp 154This operation can only be performed when the control endpoint 155is the sole open endpoint. 156.It Dv USB_GET_ALTINTERFACE Pq Vt "struct usb_alt_interface" 157Get the alternative setting number for the interface with the given 158index. 159The 160.Va uai_config_index 161is ignored in this call. 162.Bd -literal 163struct usb_alt_interface { 164 int uai_config_index; 165 int uai_interface_index; 166 int uai_alt_no; 167}; 168.Ed 169.It Dv USB_SET_ALTINTERFACE Pq Vt "struct usb_alt_interface" 170Set the alternative setting to the given number in the interface with the 171given index. 172The 173.Va uai_config_index 174is ignored in this call. 175.Pp 176This operation can only be performed when no endpoints for the interface 177are open. 178.It Dv USB_GET_NO_ALT Pq Vt "struct usb_alt_interface" 179Return the number of different alternate settings in the 180.Va uai_alt_no 181field. 182.It Dv USB_GET_DEVICE_DESC Pq Vt usb_device_descriptor_t 183Return the device descriptor. 184.It Dv USB_GET_CONFIG_DESC Pq Vt "struct usb_config_desc" 185Return the descriptor for the configuration with the given index. 186For convenience the current configuration can be specified by 187.Dv USB_CURRENT_CONFIG_INDEX . 188.Bd -literal 189struct usb_config_desc { 190 int ucd_config_index; 191 usb_config_descriptor_t ucd_desc; 192}; 193.Ed 194.It Dv USB_GET_INTERFACE_DESC Pq Vt "struct usb_interface_desc" 195Return the interface descriptor for an interface specified by its 196configuration index, interface index, and alternative index. 197For convenience the current alternative can be specified by 198.Dv USB_CURRENT_ALT_INDEX . 199.Bd -literal 200struct usb_interface_desc { 201 int uid_config_index; 202 int uid_interface_index; 203 int uid_alt_index; 204 usb_interface_descriptor_t uid_desc; 205}; 206.Ed 207.It Dv USB_GET_ENDPOINT_DESC Pq Vt "struct usb_endpoint_desc" 208Return the endpoint descriptor for the endpoint specified by its 209configuration index, interface index, alternative index, and 210endpoint index. 211.Bd -literal 212struct usb_endpoint_desc { 213 int ued_config_index; 214 int ued_interface_index; 215 int ued_alt_index; 216 int ued_endpoint_index; 217 usb_endpoint_descriptor_t ued_desc; 218}; 219.Ed 220.It Dv USB_GET_FULL_DESC Pq Vt "struct usb_full_desc" 221Return all the descriptors for the given configuration. 222.Bd -literal 223struct usb_full_desc { 224 int ufd_config_index; 225 u_int ufd_size; 226 u_char *ufd_data; 227}; 228.Ed 229The 230.Va ufd_data 231field should point to a memory area of the size given in the 232.Va ufd_size 233field. 234The proper size can be determined by first issuing a 235.Dv USB_GET_CONFIG_DESC 236and inspecting the 237.Va wTotalLength 238field. 239.It Dv USB_GET_STRING_DESC Pq Vt "struct usb_string_desc" 240Get a string descriptor for the given language ID and 241string index. 242.Bd -literal 243struct usb_string_desc { 244 int usd_string_index; 245 int usd_language_id; 246 usb_string_descriptor_t usd_desc; 247}; 248.Ed 249.It Dv USB_DO_REQUEST Pq Vt "struct usb_ctl_request" 250Send a USB request to the device on the control endpoint. 251Any data sent to/from the device is located at 252.Va ucr_data . 253The size of the transferred data is determined from the 254.Va ucr_request . 255The 256.Va ucr_addr 257field is ignored in this call. 258The 259.Va ucr_flags 260field can be used to flag that the request is allowed to 261be shorter than the requested size, and the 262.Va ucr_actlen 263will contain the actual size on completion. 264.Bd -literal 265struct usb_ctl_request { 266 int ucr_addr; 267 usb_device_request_t ucr_request; 268 void *ucr_data; 269 int ucr_flags; 270#define USBD_SHORT_XFER_OK 0x04 /* allow short reads */ 271 int ucr_actlen; /* actual length transferred */ 272}; 273.Ed 274This is a dangerous operation in that it can perform arbitrary operations 275on the device. 276Some of the most dangerous (e.g., changing the device 277address) are not allowed. 278.It Dv USB_GET_DEVICEINFO Pq Vt "struct usb_device_info" 279Get an information summary for the device. 280This call will not 281issue any USB transactions. 282.El 283.Pp 284Note that there are two different ways of addressing configurations, interfaces, 285alternatives, and endpoints: by index or by number. 286The index is the ordinal number (starting from 0) of the descriptor 287as presented by the device. 288The number is the respective number of 289the entity as found in its descriptor. 290Enumeration of descriptors 291use the index, getting and setting typically uses numbers. 292.Pp 293Example: 294all endpoints (except the control endpoint) for the current configuration 295can be found by iterating the 296.Va interface_index 297from 0 to 298.Va config_desc->bNumInterface Ns \-1 299and for each of these iterating the 300.Va endpoint_index 301from 0 to 302.Va interface_desc->bNumEndpoints . 303The 304.Va config_index 305should set to 306.Dv USB_CURRENT_CONFIG_INDEX 307and 308.Va alt_index 309should be set to 310.Dv USB_CURRENT_ALT_INDEX . 311.Sh FILES 312.Bl -tag -width ".Pa /dev/ugen Ns Ar N Ns Pa \&. Ns Ar EE" -compact 313.It Pa /dev/ugen Ns Ar N Ns Pa \&. Ns Ar EE 314Endpoint 315.Ar EE 316of device 317.Ar N . 318.El 319.Sh SEE ALSO 320.Xr usb 4 321.Sh HISTORY 322The 323.Nm 324driver 325appeared in 326.Nx 1.4 . 327.\" .Sh BUGS 328.\" The driver is not yet finished; there is no access to isochronous endpoints. 329