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usb_lookup_ep_data (9)

>> usb_lookup_ep_data (9) ( Solaris man: Ядро )

NAME

usb_lookup_ep_data - Lookup endpoint information

SYNOPSIS

#include <sys/usb/usba.h>



usb_ep_data_t *usb_lookup_ep_data(dev_info_t *dip, 
    usb_client_dev_data_t *dev_datap, uint_t interface, 
    uint_t alternate, uint_t skip, uint_t type, uint_t direction);

INTERFACE LEVEL

Solaris DDI specific (Solaris DDI)

PARAMETERS

dip

: Pointer to the device's dev_info structure.

dev_datap

: Pointer to a usb_client_dev_data_t structure containing tree.

interface

: Number of interface in which endpoint resides.

alternate

: Number of interface alternate setting in which endpoint resides.

skip

: Number of endpoints which match the requested type and direction to skip before finding one to retrieve.

type

: Type of endpoint. This is one of: USB_EP_ATTR_CONTROL, USB_EP_ATTR_ISOCH, USB_EP_ATTR_BULK, or USB_EP_ATTR_INTR. Please see usb_pipe_open(9F) for more information.

direction

: Direction of endpoint, either USB_EP_DIR_OUT or USB_EP_DIR_IN. This argument is ignored for bi-directional control endpoints.

DESCRIPTION

The usb_lookup_ep_data() function returns endpoint information from the tree embedded in client data returned from usb_get_dev_data. It operates on the current configuration (pointed to by the dev_curr_cfg field of the usb_client_dev_data_t argument). It skips the first <skip> number of endpoints it finds which match the specifications of the other arguments, and then retrieves information on the next matching endpoint it finds. Note that it does not make a copy of the data, but points to the tree itself.

RETURN VALUES

On success: the tree node corresponding to the desired endpoint.

On failure: returns NULL. Fails if dip or dev_datap are NULL, if the desired endpoint does not exist in the tree, or no tree is present in dev_datap.

CONTEXT

May be called from user, kernel or interrupt context.

EXAMPLES

Retrieve the polling interval for the second interrupt endpoint at interface 0, alt 3:

    uint8_t interval = 0;
   usb_ep_data_t *ep_node = usb_lookup_ep_data(
       dip, dev_datap, 0, 3, 1, USB_EP_ATTR_INTR, USB_EP_DIR_IN); 
   if (ep_node != NULL) {
           interval = ep_node->ep_descr.bInterval;
   }

Retrieve the maximum packet size for the first control pipe at interface 0, alt 4:

    uint16_t maxPacketSize = 0;
   usb_ep_data_t *ep_node = usb_lookup_ep_data(
       dip, dev_datap, 0, 4, 0, USB_EP_ATTR_CONTROL, 0); 
   if (ep_node != NULL) {
           maxPacketSize = ep_node->ep_descr.wMaxPacketSize;
   }