USB_STRING_IDS_N(9) Kernel Mode Gadget API USB_STRING_IDS_N(9)
NAME
usb_string_ids_n - allocate unused string IDs in batch
SYNOPSIS
int usb_string_ids_n(struct usb_composite_dev * c, unsigned n);
ARGUMENTS
c
the device whose string descriptor IDs are being allocated
n
number of string IDs to allocate
CONTEXT
single threaded during gadget setup
DESCRIPTION
Returns the first requested ID. This ID and next n-1 IDs are now valid IDs. At least provided that n is non-zero because if it is, returns
last requested ID which is now very useful information.
usb_string_ids_n() is called from bind callbacks to allocate string IDs. Drivers for functions, configurations, or gadgets will then store
that ID in the appropriate descriptors and string table.
All string identifier should be allocated using this, usb_string_id() or usb_string_ids_n() routine, to ensure that for example different
functions don't wrongly assign different meanings to the same identifier.
AUTHOR
David Brownell <dbrownell@users.sourceforge.net>
Author.
COPYRIGHT
Kernel Hackers Manual 3.10 June 2014 USB_STRING_IDS_N(9)
