Regression in next with gpiolib

Tony Lindgren tony at atomide.com
Thu Aug 31 07:02:21 PDT 2017


* Linus Walleij <linus.walleij at linaro.org> [170830 22:59]:
> On Wed, Aug 30, 2017 at 11:41 PM, Tony Lindgren <tony at atomide.com> 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.

OK thanks!

Tony



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