Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1723853

Re: Regression in next with gpiolib

From Linus Walleij <linus.walleij@linaro.org>
Newsgroups linux.kernel
Subject Re: Regression in next with gpiolib
Date 2017-08-31 08:00 +0200
Message-ID <ukqGd-1Eq-5@gated-at.bofh.it> (permalink)
References <ukj21-5gs-11@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


On Wed, Aug 30, 2017 at 11:41 PM, Tony Lindgren <tony@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.

Yours,
Linus Walleij

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

Regression in next with gpiolib Tony Lindgren <tony@atomide.com> - 2017-08-30 23:50 +0200
  Re: Regression in next with gpiolib Linus Walleij <linus.walleij@linaro.org> - 2017-08-31 08:00 +0200
    Re: Regression in next with gpiolib Tony Lindgren <tony@atomide.com> - 2017-08-31 16:10 +0200

csiph-web