USBA_HCDI_DUP_ISOC_REQ(9F) | Kernel Functions for Drivers | USBA_HCDI_DUP_ISOC_REQ(9F) |
usba_hcdi_dup_isoc_req
—
#include <sys/usb/usba/hcdi.h>
usb_isoc_req_t *
usba_hcdi_dup_isoc_req
(dev_info_t
*dip, usb_isoc_req_t *usrp,
usb_flags_t flags);
This is a private function that is not part of the stable DDI. It may be removed or changed at any time.
Note, the request may still fail even if USB_FLAGS_SLEEP is specified.
usba_hcdi_dup_isoc_req
() function is used to
duplicate an existing isochronous request, usrp.
When the USBA framework initiates an isochronous in transfer with the usba_hcdi_pipe_isoc_xfer(9E) entry point, it is the HCD driver's responsibility to receive the periodic data from the pipe. When there is data available, the HCD must duplicate the original isochronous request and copy the available data into the request structure's isoc_data member, before handing over the request structure to the USBA framework by calling the usba_hcdi_cb(9F) function.
In addition to duplicating the request, it is the callers responsibility to increase the pipe handle's request count. For more information, see usba_hcdi_pipe_isoc_xfer(9E).
The dip argument should correspond to the
HCD driver's dev_info_t structure. The
usrp pointer should correspond to the initial
isochronous request. The flags member must be
appropriate for the context. If USB_FLAGS_SLEEP
is
passed while in interrupt context, then this function may fail.
usba_hcdi_dup_isoc_req
() function may be called from
user, kernel, or
interrupt context; however, when in interrupt context, the
value of flags must be
USB_FLAGS_NOSLEEP.
usba_hcdi_dup_isoc_req
()
function returns a pointer to a duplicate isochronous request. Otherwise,
NULL is returned to indicate that the request could not be
duplicated.
September 16, 2016 | OmniOS |