Hi Rob,

On 12/07/2018 13:22:22-0600, Rob Herring wrote:

AT91 pinctrl deferred probing support is broken if the GPIO devices
haven't probed first and set gpio_banks to non-zero. The later condition
that only some GPIO devices haven't probed can't actually happen as
either all the GPIO devices have probed first or none of them have. Plus
the pinctrl driver has already returned -EINVAL, so it's not on the
deferred list to retry probing.

Fix this by consolidating the checking that all GPIO devices are probed.

Cc: Jean-Christophe Plagniol-Villard <redacted>
Cc: Linus Walleij <redacted>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: linux-arm-kernel at lists.infradead.org
Cc: linux-gpio at vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
---
This is a result of trying to remove of_platform_default_populate from 
at91 code and relying on the DT core handling populating devices. That 
changed the probe order and broke booting.

This solves part of the issue but when tested with the
of_platform_default_populate removal, many drivers will fail with
gpiod_set_value: invalid GPIO (errorpointer)

or 

gpiod_get_value: invalid GPIO (errorpointer)

This happens both before and after the pinctrl driver probed.

I didn't investigate much yet.

-- 
Alexandre Belloni, Bootlin (formerly Free Electrons)
Embedded Linux and Kernel engineering
https://bootlin.com