Re: Regression in next with gpiolib
From: Linus Walleij
Date: Thu Aug 31 2017 - 01:59:39 EST
On Wed, Aug 30, 2017 at 11:41 PM, Tony Lindgren <tony@xxxxxxxxxxx> wrote:
> Hi Timur, Linus & Grygorii,
>
> Looks like commit 108d23e322a2 ("gpiolib: request the gpio before
> querying its direction") caused a regression on at least pandaboard
> es with booting hanging shortly after gpio init.
>
> It seems to be that we're now calling request and free on all gpios
> before they are properly configured?
>
> I narrowed the hang down to gpio bank1 lines 7 and possibly 8 where
> not calling omap_gpio_free() on them makes the system boot again.
>
> These lines are used for the leds in omap4-panda-common.dtsi, and
> omap_gpio_free() will by default set the unused lines for input
> and bad things happen. I guess hardware failure could also happen
> although I have not seen it here.
>
> It seems a similar issue can exist on other platforms too,
> so it's probably a good idea to revert this for now.
I reverted it for now.
Yours,
Linus Walleij