gpio: Remove VLA from gpiolib

The new challenge is to remove VLAs from the kernel
(see https://lkml.org/lkml/2018/3/7/621) to eventually
turn on -Wvla.

Using a kmalloc array is the easy way to fix this but kmalloc is still
more expensive than stack allocation. Introduce a fast path with a
fixed size stack array to cover most chip with gpios below some fixed
amount. The slow path dynamically allocates an array to cover those
chips with a large number of gpios.

Reviewed-by: Geert Uytterhoeven <[email protected]>
Reviewed-by: Phil Reid <[email protected]>
Reviewed-and-tested-by: Lukas Wunner <[email protected]>
Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Laura Abbott <[email protected]>
Reviewed-by: Andy Shevchenko <[email protected]>
Signed-off-by: Linus Walleij <[email protected]>

0 files changed, 0 insertions, 0 deletions