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Message-ID: <1545016504.29293.10.camel@mhfsdcap03>
Subject: Re: [PATCH] eint: add gpio vritual number select
From:   Chuanjia Liu <Chuanjia.Liu@mediatek.com>
To:     Sean Wang <sean.wang@kernel.org>
CC:     Linus Walleij <linus.walleij@linaro.org>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        <linux-mediatek@lists.infradead.org>,
        <linux-arm-kernel@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>, <hongkun.cao@mediatek.com>,
        <youlin.pei@mediatek.com>, <eddie.huang@mediatek.com>,
        <zhiyong.tao@mediatek.com>, <hailong.fan@mediatek.com>
Date:   Mon, 17 Dec 2018 11:15:04 +0800
In-Reply-To: <CAGp9LzpcRCMWSn-u6K6+eRT=Zr8PR22Vd381miyhVYbF87N02g@mail.gmail.com>
References: <1544693783-25079-1-git-send-email-chuanjia.liu@mediatek.com>
         <CAGp9LzpcRCMWSn-u6K6+eRT=Zr8PR22Vd381miyhVYbF87N02g@mail.gmail.com>
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On Thu, 2018-12-13 at 11:33 -0800, Sean Wang wrote:
> On Thu, Dec 13, 2018 at 1:36 AM <chuanjia.liu@mediatek.com> wrote:
> >
> > From: Chuanjia Liu <Chuanjia.Liu@mediatek.com>
> >
> > This patch add gpio vritual number select,avoid virtual gpio set SMT.
> 
> s/gpio/GPIO/
> s/vritual/virtual/
> 
> Virtual GPIOs you said here that means these pins only used inside SoC
> and not being exported to outside SoC, right? It seems this kind of
> pins doesn't need SMT.
> 
Yes,virtual gpio only used inside SOC and these pins doesn't need set
SMT
> >
> > Signed-off-by: Chuanjia Liu <Chuanjia.Liu@mediatek.com>
> > ---
> >  drivers/pinctrl/mediatek/mtk-eint.h              |    1 +
> >  drivers/pinctrl/mediatek/pinctrl-mt8183.c        |    1 +
> >  drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c |    9 ++++++---
> >  3 files changed, 8 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/pinctrl/mediatek/mtk-eint.h b/drivers/pinctrl/mediatek/mtk-eint.h
> > index 48468d0..c16beaf 100644
> > --- a/drivers/pinctrl/mediatek/mtk-eint.h
> > +++ b/drivers/pinctrl/mediatek/mtk-eint.h
> > @@ -37,6 +37,7 @@ struct mtk_eint_hw {
> >         u8              ports;
> >         unsigned int    ap_num;
> >         unsigned int    db_cnt;
> > +       unsigned int    vir_start;
> >  };
> >
> >  struct mtk_eint;
> > diff --git a/drivers/pinctrl/mediatek/pinctrl-mt8183.c b/drivers/pinctrl/mediatek/pinctrl-mt8183.c
> > index 6262fd3..bbeafd3 100644
> > --- a/drivers/pinctrl/mediatek/pinctrl-mt8183.c
> > +++ b/drivers/pinctrl/mediatek/pinctrl-mt8183.c
> > @@ -497,6 +497,7 @@
> >         .ports     = 6,
> >         .ap_num    = 212,
> >         .db_cnt    = 13,
> > +       .vir_start = 180,
> >  };
> >
> >  static const struct mtk_pin_soc mt8183_data = {
> > diff --git a/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c b/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
> > index 4a9e0d4..ca3bae1 100644
> > --- a/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
> > +++ b/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
> > @@ -289,9 +289,12 @@ static int mtk_xt_set_gpio_as_eint(void *data, unsigned long eint_n)
> >         if (err)
> >                 return err;
> >
> > -       err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_SMT, MTK_ENABLE);
> > -       if (err)
> > -               return err;
> > +       if (gpio_n < hw->eint->hw->vir_start) {
> > +               err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_SMT,
> > +                                      MTK_ENABLE);
> > +               if (err)
> > +                       return err;
> > +       }
> 
> The changes will break these SoCs without a properly configured vir_start.
> 
> If SMT seems unnecessary for these kinds of virtual GPIOs pin in the
> path, we can do it as
> 
> err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_SMT,
>                                         MTK_ENABLE);
> /* please add comments for the exclusion condition */
> if (err && err != -ENOTSUPP)
>         return err;
> 
> If there is getting much special on certain pins between SoCs, and
> then we can consider creating a desc->flag to split logic.

Yes,SMT unnecessary for these kinds of virtual GPIOS pin in the path,if
do it as
	err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_SMT,
                                        MTK_ENABLE);
	if (err && err != -ENOTSUPP)
      		  return err;
I wonder if system will lose -ENOTSUPP information when smt was not
successfully set by real gpio?
> 
> >
> >         return 0;
> >  }
> > --
> > 1.7.9.5