man pages section 9: DDI and DKI Kernel Functions

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Updated: July 2014
 
 

usb_lookup_ep_data(9F)

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;
    }

Attributes

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE
ATTRIBUTE VALUE
Architecture
PCI-based systems
Interface Stability
Committed
Availability
system/io/usb

See Also

attributes(5), usb_get_dev_data(9F), usb_pipe_open(9F), usb_cfg_descr (9S), usb_if_descr(9S), usb_ep_descr(9S)