Linux Kernel
3.7.1
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#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/string.h>
#include <linux/device.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
Go to the source code of this file.
EXPORT_SYMBOL_GPL | ( | usb_descriptor_fillbuf | ) |
EXPORT_SYMBOL_GPL | ( | usb_gadget_config_buf | ) |
EXPORT_SYMBOL_GPL | ( | usb_copy_descriptors | ) |
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read |
usb_copy_descriptors - copy a vector of USB descriptors : null-terminated vector to copy Context: initialization code, which may sleep
This makes a copy of a vector of USB descriptors. Its primary use is to support usb_function objects which can have multiple copies, each needing different descriptors. Functions may have static tables of descriptors, which are used as templates and customized with identifiers (for interfaces, strings, endpoints, and more) as needed by a given function instance.
int usb_descriptor_fillbuf | ( | void * | buf, |
unsigned | buflen, | ||
const struct usb_descriptor_header ** | src | ||
) |
usb_descriptor_fillbuf - fill buffer with descriptors : Buffer to be filled : Size of buf : Array of descriptor pointers, terminated by null pointer.
Copies descriptors into the buffer, returning the length or a negative error code if they can't all be copied. Useful when assembling descriptors for an associated set of interfaces used as part of configuring a composite device; or in other cases where sets of descriptors need to be marshaled.
int usb_gadget_config_buf | ( | const struct usb_config_descriptor * | config, |
void * | buf, | ||
unsigned | length, | ||
const struct usb_descriptor_header ** | desc | ||
) |
usb_gadget_config_buf - builts a complete configuration descriptor : Header for the descriptor, including characteristics such as power requirements and number of interfaces. : Null-terminated vector of pointers to the descriptors (interface, endpoint, etc) defining all functions in this device configuration. : Buffer for the resulting configuration descriptor. : Length of buffer. If this is not big enough to hold the entire configuration descriptor, an error code will be returned.
This copies descriptors into the response buffer, building a descriptor for that configuration. It returns the buffer length or a negative status code. The config.wTotalLength field is set to match the length of the result, but other descriptor fields (including power usage and interface count) must be set by the caller.
Gadget drivers could use this when constructing a config descriptor in response to USB_REQ_GET_DESCRIPTOR. They will need to patch the resulting bDescriptorType value if USB_DT_OTHER_SPEED_CONFIG is needed.