USB_ALTNUM_TO_ALTSET(9) USB Core APIs USB_ALTNUM_TO_ALTSET(9)NAMEusb_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.
Don't call this function unless you are bound to the intf interface or
you have locked the device!
COPYRIGHTKernel Hackers Manual 3.8. June 2014 USB_ALTNUM_TO_ALTSET(9)