From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Subject: Re: [PATCH v2] gpiolib: Show correct direction from the beginning
Date: Mon, 1 Oct 2018 15:36:22 +0200
Message-ID: <CAPybu_1P-RWCP8yjQKkFYAX11KtYGhAfASY24Q_NZ19PD09gxA@mail.gmail.com>
References: <20180921103604.13361-1-ricardo.ribalda@gmail.com>
 <20180921103604.13361-2-ricardo.ribalda@gmail.com> <153803107307.119890.10052910965015646333@swboyd.mtv.corp.google.com>
 <ffe11a8c-368b-8c74-54a7-a088c3997032@kernel.org> <3e07cab8-0f3e-7474-8f6d-e6bb16e8f998@codeaurora.org>
 <5aea282d-6fc9-cd70-cec4-10f28aa819b9@codeaurora.org> <CAOZdJXUUWUWHzus+3sbEXbW_q92e+SSzTQJCqCyQp6Y6_HOo3g@mail.gmail.com>
 <D3E6F4C4-E1C4-4D88-B118-878576BF5281@gmail.com> <CACRpkdawwrpEe6AAfdaxw6OMFXkCnq0gpznk1Up5p1=Wigx_2g@mail.gmail.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="UTF-8"
Return-path: <linux-kernel-owner@vger.kernel.org>
In-Reply-To: <CACRpkdawwrpEe6AAfdaxw6OMFXkCnq0gpznk1Up5p1=Wigx_2g@mail.gmail.com>
Sender: linux-kernel-owner@vger.kernel.org
To: Linus Walleij <linus.walleij@linaro.org>
Cc: Timur Tabi <timur@kernel.org>, Jeffrey Hugo <jhugo@codeaurora.org>, Stephen Boyd <swboyd@chromium.org>, LKML <linux-kernel@vger.kernel.org>, linux-gpio <linux-gpio@vger.kernel.org>
List-Id: linux-gpio@vger.kernel.org

Hi Linus
On Mon, Oct 1, 2018 at 1:54 PM Linus Walleij <linus.walleij@linaro.org> wrote:
>
> On Fri, Sep 28, 2018 at 9:30 PM Ricardo Ribalda Delgado
> <ricardo.ribalda@gmail.com> wrote:
>
> > How do we proceed from here? Can you fix your driver somehow to
> > init the valid mask before enabling the gpio?
>
> Just include a hunk to the qcom driver reordering this call
> at the same time. No need to make it separate patches,
> it need to be tested together anyways.
>
> I guess just switch the order of these two:
>
>         ret = gpiochip_add_data(&pctrl->chip, pctrl);
>         if (ret) {
>                 dev_err(pctrl->dev, "Failed register gpiochip\n");
>                 return ret;
>         }
>
>         ret = msm_gpio_init_valid_mask(chip, pctrl);
>         if (ret) {
>                 dev_err(pctrl->dev, "Failed to setup irq valid bits\n");
>                 gpiochip_remove(&pctrl->chip);
>                 return ret;
>         }
>

the problem is that valid_mask is not a long/integer, is a struct that
needs to be malloced, and is malloc at gpiochip_add_data :(

Maybe we need a callback from the driver to init that mask just after
the allocation?

A fast grep shows that the only driver using need_valid_mask (not for
irq) is msm:

ricardo@neopili:~/curro/kernel-upstream$ git grep "need_valid_mask ="
| grep -v irq
drivers/gpio/gpiolib.c: gpiochip->need_valid_mask = true;
drivers/pinctrl/intel/pinctrl-cherryview.c: bool need_valid_mask =
!dmi_check_system(chv_no_valid_mask);
drivers/pinctrl/qcom/pinctrl-msm.c: chip->need_valid_mask =
msm_gpio_needs_valid_mask(pctrl);

so hacking something in the driver might not be a terrible idea.



Also

> > Do we need to make more severe changes on the core?
>
> Don't think so.
>
> Yours,
> Linus Walleij



-- 
Ricardo Ribalda