Pull GPIO fixes from Linus Walleij:
"More GPIO fixes. Most prominent the gpiod_to_irq() fix brought to my
attention by Hans de Goede. The hardening patch is a consequence of
the reasoning around that bug.
- It was discovered that too many parts of the kernel does not
respect gpiod_to_irq() returning zero for an invalid IRQ. While
this gets fixed, we need to make it return negative errorcodes
again.
- Harden the library a bit when passed error pointers. It is a bug
to use these, but let's be helpful and warn the users.
- Fix an uninitialized spinlock in the 104-idi-48 driver"
* tag 'gpio-v4.7-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
gpio: make library immune to error pointers
gpio: make sure gpiod_to_irq() returns negative on NULL desc
gpio: 104-idi-48: Fix missing spin_lock_init for ack_lock