I think GPIO_PIN_ACCESS_32 4th argument is a32->change_pins. https://svnweb.freebsd.org/base/head/sys/dev/gpio/gpioc.c?view=markup#l195
A commit references this bug: Author: ian Date: Thu Apr 25 22:27:56 UTC 2019 New revision: 346713 URL: https://svnweb.freebsd.org/changeset/base/346713 Log: Fix typo: the 4th argument to GPIO_PIN_ACCESS_32 is the set of pins to change, not the variable used to return the original pin state. PR: 237378 Reported by: Mori Hiroki <yamori813@yahoo.co.jp> Changes: head/sys/dev/gpio/gpioc.c
A commit references this bug: Author: ian Date: Tue Apr 30 00:58:43 UTC 2019 New revision: 346938 URL: https://svnweb.freebsd.org/changeset/base/346938 Log: MFC r346713: Fix typo: the 4th argument to GPIO_PIN_ACCESS_32 is the set of pins to change, not the variable used to return the original pin state. PR: 237378 Reported by: Mori Hiroki <yamori813@yahoo.co.jp> Changes: _U stable/12/ stable/12/sys/dev/gpio/gpioc.c