개요

• 솔라나라에 설명된 어플리케이션에 대해 맨 페이지를 찾아 출력한다.
• MAN 페이지에 대한 설명은 윈디하나의 솔라나라: MAN 페이지을 참고하자.
• svcadm(8)을 검색하려면 섹션에서 8 을 선택하고, 맨 페이지 이름에 svcadm을 입력하고 검색을 누른다.

usb_get_max_pkts_per_isoc_request(9f)

Kernel Functions                         usb_get_max_pkts_per_isoc_request(9F)



NAME
       usb_get_max_pkts_per_isoc_request  -  Get  maximum  number  of  packets
       allowed per isochronous request

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

       uint_t usb_get_max_pkts_per_isoc_request(dev_info_t *dip);

INTERFACE LEVEL
       Solaris DDI specific (Solaris DDI)

PARAMETERS
       dip    Pointer to the device's dev_info structure.


DESCRIPTION
       The usb_get_max_pkts_per_isoc_request() function  returns  the  maximum
       number  of isochronous packets per request that the host control driver
       can support. This number can be used to determine the maximum amount of
       data  which can be handled by a single isochronous request. That length
       is found by:



         max = usb_get_max_pkts_per_isoc_request(dip) * endpoint_max_packet_size;



       where endpoint_max_packet_size  is  the  wMaxPacketSize  field  of  the
       isochronous endpoint over which the transfer will take place.

RETURN VALUES
       On  success,  the  usb_get_current_frame_number()  function returns the
       maximum number of isochronous pkts per request. On failure  it  returns
       0. The function fails if dip is NULL.

CONTEXT
       May be called from user, kernel or interrupt context.

EXAMPLES
         /*
          * Set up to receive periodic isochronous data, requesting
          * the maximum amount for each transfer.
          */

         int pkt;
         /* Get max packet size from endpoint descriptor. */
         uint_t ep_max_pkt_size = ep_descr.wMaxPacketSize;
         uint_t isoc_pkts_count = usb_get_max_pkts_per_isoc_request(dip);

         /*
          * Allocate an isoc request, specifying the max number of packets
          * and the greatest size transfer possible.
          */
         usb_isoc_req_t *isoc_req = usb_alloc_isoc_req(dip,
             isoc_pkts_count,
             isoc_pkts_count * ep_max_pkt_size,
             USB_FLAGS_SLEEP);

         /* Init each packet descriptor for maximum size. */
         for (pkt = 0; pkt < isoc_pkts_count; pkt++) {
             isoc_req->isoc_pkt_descr[pkt].isoc_pkt_length = ep_max_pkt_size;

         }


         /* Set the length of a packet in the request too. */
         isoc_req->isoc_pkts_length = ep_max_pkt_size;

         /* Other isoc request initialization. */
         ...
         ...

         if (usb_pipe_isoc_xfer(pipe, isoc_req, USB_FLAGS_NOSLEEP) != USB_SUCCESS) {
             ...
         }


ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       tab()  box; cw(2.75i) |cw(2.75i) lw(2.75i) |lw(2.75i) ATTRIBUTE TYPEAT‐
       TRIBUTE VALUE _ ArchitecturePCI-based systems  _  Interface  Stability‐
       Committed _ Availabilitysystem/io/usb


SEE ALSO
       attributes(7), usb_alloc_request(9F), usb_get_current_frame_number(9F),
       usb_pipe_isoc_xfer(9F). usb_ep_descr(9S), usb_isoc_request(9S)



Oracle Solaris 11.4               5 Jan 2004
                                         usb_get_max_pkts_per_isoc_request(9F)