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struct_usb_host_config(9) [centos man page]

USB_HOST_CONF(9) Host-Side Data Types and Macro STRUCT USB_HOST_CONF(9) NAME
struct_usb_host_config - representation of a device's configuration SYNOPSIS
struct usb_host_config { struct usb_config_descriptor desc; char * string; struct usb_interface_assoc_descriptor * intf_assoc[USB_MAXIADS]; struct usb_interface * interface[USB_MAXINTERFACES]; struct usb_interface_cache * intf_cache[USB_MAXINTERFACES]; unsigned char * extra; int extralen; }; MEMBERS
desc the device's configuration descriptor. string pointer to the cached version of the iConfiguration string, if present for this configuration. intf_assoc[USB_MAXIADS] list of any interface association descriptors in this config interface[USB_MAXINTERFACES] array of pointers to usb_interface structures, one for each interface in the configuration. The number of interfaces is stored in desc.bNumInterfaces. These pointers are valid only while the the configuration is active. intf_cache[USB_MAXINTERFACES] array of pointers to usb_interface_cache structures, one for each interface in the configuration. These structures exist for the entire life of the device. extra pointer to buffer containing all extra descriptors associated with this configuration (those preceding the first interface descriptor). extralen length of the extra descriptors buffer. DESCRIPTION
USB devices may have multiple configurations, but only one can be active at any time. Each encapsulates a different operational environment; for example, a dual-speed device would have separate configurations for full-speed and high-speed operation. The number of configurations available is stored in the device descriptor as bNumConfigurations. A configuration can contain multiple interfaces. Each corresponds to a different function of the USB device, and all are available whenever the configuration is active. The USB standard says that interfaces are supposed to be numbered from 0 to desc.bNumInterfaces-1, but a lot of devices get this wrong. In addition, the interface array is not guaranteed to be sorted in numerical order. Use usb_ifnum_to_if to look up an interface entry based on its number. Device drivers should not attempt to activate configurations. The choice of which configuration to install is a policy decision based on such considerations as available power, functionality provided, and the user's desires (expressed through userspace tools). However, drivers can call usb_reset_configuration to reinitialize the current configuration and all its interfaces. COPYRIGHT
Kernel Hackers Manual 3.10 June 2014 STRUCT USB_HOST_CONF(9)

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usb_other_speed_cfg_descr(9S)				    Data Structures for Drivers 			     usb_other_speed_cfg_descr(9S)

usb_other_speed_cfg_descr - USB other speed configuration descriptor SYNOPSIS
#include <sys/usb/usba.h> INTERFACE LEVEL
Solaris DDI specific (Solaris DDI) DESCRIPTION
The usb_other_speed_cfg_descr_t configuration descriptor defines how fields of a high speed device's configuration descriptor change if that device is run at its other speed. Fields of this descriptor reflect configuration descriptor field changes if a device's speed is changed from full to high speed, or from high to full speed. Please refer to Section 9.6.4 of the USB 2.0 specification. The USB 2.0 specification is available at This descriptor has the following fields: uint8_t bLength Size of this descriptor, in bytes. uint8_t bDescriptorType Set to USB_DESCR_TYPE_OTHER_SPEED_CFG. uint16_t wTotalLength Total length of data returned */ including all descriptors in the current other-speed configuration. uint8_t bNumInterfaces Number of interfaces in the selected configuration. uint8_t bConfigurationValue ID of the current other-speed configuration (1-based). uint8_t iConfiguration Configuration value. Valid if > 0. Pass to usb_get_string_descr(9F) to retrieve string. uint8_t bmAttributes Configuration characteristics [See usb_cfg_descr(9S).] uint8_t bMaxPower Maximum power consumption in 2mA units. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Architecture |PCI-based systems | +-----------------------------+-----------------------------+ |Interface stability |Committed | +-----------------------------+-----------------------------+ |Availability |SUNWusbu | +-----------------------------+-----------------------------+ SEE ALSO
attributes(5), usb_get_alt_if(9F), usb_get_cfg(9F), usb_get_dev_data(9F), usb_get_string_descr(9F), usb_parse_data(9F), usb_cfg_descr(9S), usb_ctrl_request(9S), usb_dev_descr(9S), usb_dev_qlf_descr(9S) SunOS 5.11 5 Jan 2004 usb_other_speed_cfg_descr(9S)
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