usb_string (9)

int usb_string(struct usb_device * dev, int index, char * buf, size_t size);

dev

the device whose string descriptor is being retrieved

index

the number of the descriptor

buf

where to put the string

size

how big is “buf”?

!in_interrupt ()

This converts the UTF-16LE encoded strings returned by devices, from usb_get_string_descriptor, to null-terminated UTF-8 encoded ones that are more usable in most kernel contexts. Note that this function chooses strings in the first language supported by the device.

This call is synchronous, and may not be used in an interrupt context.

length of the string (>= 0) or usb_control_msg status (< 0).