USB_CTRL_REQUEST(9S)     Data Structures for Drivers    USB_CTRL_REQUEST(9S)
NAME
       usb_ctrl_req, usb_ctrl_req_t, usb_ctrl_request - USB control pipe
       request structure
SYNOPSIS
       #include <sys/usb/usba.h>
INTERFACE LEVEL
       illumos DDI specific (illumos DDI)
DESCRIPTION
       A control request is used to send device commands (or requests) and
       to read status. Please refer to Section 
5.5 of the 
USB 2.0       specification for information on control pipes. For information on
       formatting requests, see Section 
9.3 of the 
USB 2.0 specification.
       The USB 2.0 specification is available at 
www.usb.org.
STRUCTURE MEMBERS
       The fields in the usb_ctrl_req_t are used to format a control
       request:
           uint8_t      ctrl_bmRequestType; /* characteristics of request */
           uint8_t      ctrl_bRequest;  /* specific request             */
           uint16_t     ctrl_wValue;    /* varies according to request  */
           uint16_t     ctrl_wIndex;    /* index or offset              */
           uint16_t     ctrl_wLength;   /* number of bytes to xfer      */
           mblk_t       *ctrl_data;     /* data for the data phase  */
                                        /* IN or OUT: allocated by client */
           uint_t       ctrl_timeout;   /* time until  USBA framework */
                                        /* retires req, in seconds */
                                        /* If set to zero, defaults to 5 sec */
           usb_opaque_t    ctrl_client_private; /* client private info */
           usb_req_attrs_t ctrl_attributes; /* attrib. for this req */
           /* Normal callback function, called upon completion. */
           void       (*ctrl_cb)(
                          usb_pipe_handle_t ph, struct usb_ctrl_req *req);
           /* Exception callback function, for error handling. */
           void       (*ctrl_exc_cb)(
                          usb_pipe_handle_t ph, struct usb_ctrl_req *req);
           usb_cr_t   ctrl_completion_reason; /* overall success status */
                                           /* See 
usb_completion_reason(9S) */
           usb_cb_flags_t  ctrl_cb_flags; /* recovery done by callback hndlr */
                                         /* See 
usb_callback_flags(9S) */
       Request attributes define special handling for transfers. The
       following attributes are valid for control requests:       
USB_ATTRS_SHORT_XFER_OK                                  Accept transfers where less data is
                                  received than expected.       
USB_ATTRS_AUTOCLEARING                                  Have USB framework reset pipe and clear
                                  functional stalls automatically on
                                  exception.       
USB_ATTRS_PIPE_RESET                                  Have USB framework reset pipe
                                  automatically on exception.
       Please see 
usb_request_attributes(9S) for more information.
       The following definitions directly pertain to fields in the USB
       control request structure. (See Section  
9.3 of the 
USB 2.0       specification.)
         Direction bitmasks of a control request's ctrl_bmRequestType field
         (USB 2.0 spec, section 9.3.1)
              USB_DEV_REQ_HOST_TO_DEV     | Host to device direction
              USB_DEV_REQ_DEV_TO_HOST     | Device to host direction
              USB_DEV_REQ_DIR_MASK        | Bitmask of direction bits
         Request type bitmasks of a control request's ctrl_bmRequestType field
         (USB 2.0 spec, section 9.3.1)
              USB_DEV_REQ_TYPE_STANDARD   | USB 2.0 defined command
                                          | for all USB devices
              USB_DEV_REQ_TYPE_CLASS      | USB 2.0 defined
                                          | class-specific command
              USB_DEV_REQ_TYPE_VENDOR     | Vendor-specific command
              USB_DEV_REQ_TYPE_MASK       | Bitmask of request type bits
         Recipient bitmasks of a control request's ctrl_bmRequestType field
         (USB 2.0 spec, section 9.3.1)
              USB_DEV_REQ_RCPT_DEV        | Request is for device
              USB_DEV_REQ_RCPT_IF         | Request is for interface
              USB_DEV_REQ_RCPT_EP         | Request is for endpoint
              USB_DEV_REQ_RCPT_OTHER      | Req is for other than above
              USB_DEV_REQ_RCPT_MASK       | Bitmask of request recipient bits
         Standard requests (USB 2.0 spec, section 9.4)
              USB_REQ_GET_STATUS          | Get status of device, endpoint
                                          |or interface (9.4.5)
              USB_REQ_CLEAR_FEATURE       | Clear feature specified by
                                          |wValue field (9.4.1)
              USB_REQ_SET_FEATURE         | Set feature specified by
                                          |       wValue field (9.4.9)
              USB_REQ_SET_ADDRESS         | Set address specified by
                                          |       wValue field (9.4.6)
              USB_REQ_GET_DESCR           | Get descr for item/idx in
                                          |       wValue field (9.4.3)
              USB_REQ_SET_DESCR           | Set descr for item/idx in
                                          |       wValue field (9.4.8)
              USB_REQ_GET_CFG             | Get current device
                                          |        configuration (9.4.2)
              USB_REQ_SET_CFG             | Set current device
                                          |        configuration (9.4.7)
              USB_REQ_GET_IF              | Get alternate interface
                                          |       setting (9.4.4)
              USB_REQ_SET_IF              | Set alternate interface
                                          |       setting (9.4.10)
              USB_REQ_SYNC_FRAME          | Set and report an endpoint's
                                          |       sync frame (9.4.11)
         Unicode language ID, used as wIndex for USB_REQ_SET/GET_DESCRIPTOR
              USB_LANG_ID                 | Unicode English Lang ID for
                                          | parsing str descr
ATTRIBUTES
       See 
attributes(7) for descriptions of the following attributes:
       +--------------------+-------------------+
       |  ATTRIBUTE TYPE    |  ATTRIBUTE VALUE  |
       +--------------------+-------------------+
       |Architecture        | PCI-based systems |
       +--------------------+-------------------+
       |Interface stability | Committed         |
       +--------------------+-------------------+
SEE ALSO
       usb_alloc_request(9F), 
usb_pipe_bulk_xfer(9F),       
usb_pipe_ctrl_xfer(9F), 
usb_pipe_intr_xfer(9F),       
usb_pipe_isoc_xfer(9F), 
usb_bulk_request(9S), 
usb_callback_flags(9S),       
usb_completion_reason(9S), 
usb_intr_request(9S),       
usb_isoc_request(9S), 
usb_request_attributes(9S)                               January 5, 2004          USB_CTRL_REQUEST(9S)