usb_get_string_descr(9F) Kernel Functions for Drivers usb_get_string_descr(9F)NAMEusb_get_string_descr - Get string descriptor from device
SYNOPSIS
#include <sys/usb/usba.h>
int usb_get_string_descr(dev_info_t *dip, uint16_t langid, uint8_t
index, char *buf, size_t buflen);
INTERFACE LEVEL
Solaris DDI specific (Solaris DDI)
PARAMETERS
dip
Pointer to the device's dev_info structure.
langid
Language ID. Currently only USB_LANG_ID (English ascii) is valid.
index
String index indicating descriptor to retrieve.
buf
Address into which the string descriptor is placed.
buflen
Size of buf in bytes.
DESCRIPTION
The usb_get_string_descr() function retrieves a parsed string descrip‐
tor from a device. dip specifies the device, while index indicates
which descriptor to return.
String descriptors provide information about other descriptors, or
information that is encoded in other descriptors, in readable form.
Many descriptor types have one or more index fields which identify
string descriptors. (See Sections 9.5 and 9.6 of the USB 2.0 specifi‐
cation.) For example, a configuration descriptor's seventh byte con‐
tains the string descriptor index describing a specific configuration.
Retrieved descriptors that do not fit into buflen bytes are truncated.
All returned descriptors are null-terminated.
RETURN VALUES
USB_SUCCESS String descriptor is returned in buf.
USB_INVALID_ARGS dip or buf are NULL, or index or buflen
is 0.
USB_FAILURE Descriptor cannot be retrieved.
CONTEXT
May be called from user or kernel context.
EXAMPLES
/* Get the first string descriptor. */
char buf[SIZE];
if (usb_get_string_descr(
dip, USB_LANG_ID, 0, buf, SIZE) == USB_SUCCESS) {
cmn_err (CE_NOTE, "%s%d: %s",
ddi_driver_name(dip), ddi_get_instance(dip), buf);
}
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Architecture │PCI-based systems │
├─────────────────────────────┼─────────────────────────────┤
│Interface stability │Evolving │
├─────────────────────────────┼─────────────────────────────┤
│Availability │SUNWusb │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOattributes(5), usb_get_dev_data(9F), usb_string_descr(9S)SunOS 5.10 5 Jan 2004 usb_get_string_descr(9F)
