USB_LOOKUP_EP_DATA(9F) Kernel Functions for Drivers USB_LOOKUP_EP_DATA(9F)
usb_lookup_ep_data - Lookup endpoint information
#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);
illumos DDI specific (illumos DDI)
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_xopen(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.
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.
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.
May be called from user, kernel or interrupt context.
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;
}
See attributes(7) for descriptions of the following attributes:
+--------------------+-------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-------------------+
|Architecture | PCI-based systems |
+--------------------+-------------------+
|Interface stability | Committed |
+--------------------+-------------------+
attributes(7), usb_get_dev_data(9F), usb_pipe_open(9F),
usb_cfg_descr(9S), usb_ep_descr(9S), usb_if_descr(9S)
September 16, 2016 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
illumos DDI specific (illumos 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_xopen(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(7) for descriptions of the following attributes:
+--------------------+-------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-------------------+
|Architecture | PCI-based systems |
+--------------------+-------------------+
|Interface stability | Committed |
+--------------------+-------------------+
SEE ALSO
attributes(7), usb_get_dev_data(9F), usb_pipe_open(9F),
usb_cfg_descr(9S), usb_ep_descr(9S), usb_if_descr(9S)
September 16, 2016 USB_LOOKUP_EP_DATA(9F)