usb_altnum_to_altset(9)
NAME
usb_altnum_to_altsetting - get the altsetting structure with a given
alternate setting number.
SYNOPSIS
struct usb_host_interface *
usb_altnum_to_altsetting(const struct usb_interface * intf,
unsigned int altnum);
ARGUMENTS
- intf
- the interface containing the altsetting in question
- altnum
- the desired alternate setting number
DESCRIPTION
This searches the altsetting array of the specified interface for an
entry with the correct bAlternateSetting value and returns a pointer to
that entry, or null.
Note that altsettings need not be stored sequentially by number, so it
would be incorrect to assume that the first altsetting entry in the
array corresponds to altsetting zero. This routine helps device drivers
avoid such mistakes.
Donīt call this function unless you are bound to the intf interface or
you have locked the device!