USBA_HCDI_CB(9F) Kernel Functions for Drivers USBA_HCDI_CB(9F)

usba_hcdi_cb
USBA transfer callback

#include <sys/usb/usba/hcdi.h>

void
usba_hcdi_cb(usba_pipe_handle_data_t *ph, usb_opaque_t req, ucb_cr_t cr);

Volatile - illumos USB HCD private function

This is a private function that is not part of the stable DDI. It may be removed or changed at any time.

ph
A pointer to the USBA pipe handle that was passed to the HCD driver during a call to the usba_hcdi_pipe_open(9E) entry point.
req
A pointer to the request structure that is being completed.
cr
The completion code for the request.

The usba_hcdi_cb() function is used when the HCD controller has completed processing a USB transfer request, whether successfully or not.

The USB transfer will have been initiated by a call to usba_hcdi_pipe_bulk_xfer(9E), usba_hcdi_pipe_ctrl_xfer(9E), usba_hcdi_pipe_intr_xfer(9E), or usba_hcdi_pipe_isoc_xfer(9E). If the transfer initiated was a periodic transfer (certain Interrupt-IN and Isochronous-IN transfers), then there may be more than one callback performed over the life of the transfer.

This function must not be used if the HCD driver returned a value other than USB_SUCCESS to one of the transfer initialization functions listed above. For more information on transfer request handling, see usba_hcdi(9E).

The ph argument corresponds to the USBA framework's pipe handle that was given to the HCDI when the pipe was opened. See usba_hcdi_pipe_open(9E) and usba_hcdi(9E) for more information.

The req argument is one of the four request structures, usb_bulk_req(9S), usb_ctrl_req(9S), usb_intr_req(9S), or usb_isoc_req(9S), which have been cast to the type usb_opaque_t. The caller should ensure that all appropriate members of the request structure have been filled in. For example, if expecting data from the device and the request has completed successfully, then that data should be copied into the request structure's mblk(9S) prior to handing the request structure to the usb_hcdi_cb() function. Similarly, the usb_isoc_req(9S) structure's isoc_pkt_descr member should be filled in with the appropriate data.

Once the request structure has been passed to the usba_hcdi_cb() function, the HCD driver must not access the structure ever again. It should be treated as freed memory.

The cr argument us used to indicate whether the transfer was successful or not. If cr is set to USB_CR_OK that indicates that the transfer completed successfully. This should also be used when a permitted short transfer has occurred. Otherwise, it should be set to one of the completion reasons.

The HCD driver should not hold its own internal locks across a call to the usba_hcdi_cb() function. It is possible that the driver will have once of its usba_hcdi(9E) entry points called based on the return value specified.

The usba_hcdi_cb() function may be called from user, kernel, or interrupt context.

usba_hcdi(9E), usba_hcdi_pipe_bulk_xfer(9E), usba_hcdi_pipe_ctrl_xfer(9E), usba_hcdi_pipe_intr_xfer(9E), usba_hcdi_pipe_isoc_xfer(9E), usba_hcdi_pipe_open(9E), mblk(9S), usb_bulk_req(9S), usb_ctrl_req(9S), usb_intr_req(9S), usb_isoc_req(9S)
November 26, 2017 OmniOS