Re: [PATCH RESEND] pinctrl: mediatek: Fix trigger type setting follow for unexpected interrupt

From: Nicolas Boichat <drinkcat@chromium.org>
To: Hailong Fan <hailong.fan@mediatek.com>
Cc: Sean Wang <sean.wang@kernel.org>,
	Linus Walleij <linus.walleij@linaro.org>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	"moderated list:ARM/Mediatek SoC support" 
	<linux-mediatek@lists.infradead.org>,
	"open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
	linux-arm Mailing List <linux-arm-kernel@lists.infradead.org>,
	lkml <linux-kernel@vger.kernel.org>,
	youlin.pei@mediatek.com,
	srv_heupstream <srv_heupstream@mediatek.com>,
	Chen-Tsung Hsieh <chentsung@chromium.org>,
	gtk_pangao@mediatek.com, Hanks Chen <hanks.chen@mediatek.com>,
	Yong Wu <yong.wu@mediatek.com>
Subject: Re: [PATCH RESEND] pinctrl: mediatek: Fix trigger type setting follow for unexpected interrupt
Date: Thu, 21 Jan 2021 16:55:25 +0800	[thread overview]
Message-ID: <CANMq1KBqKUofLaM+OEaTq6PSeYomNSLvn65c+Wyi1cKsLDNboQ@mail.gmail.com> (raw)
In-Reply-To: <20210121075149.1310-1-hailong.fan@mediatek.com>

On Thu, Jan 21, 2021 at 3:52 PM Hailong Fan <hailong.fan@mediatek.com> wrote:
>
> When flipping the polarity will be generated interrupt under certain
> circumstances, but GPIO external signal has not changed.
> Then, mask the interrupt before polarity setting, and clear the
> unexpected interrupt after trigger type setting completed.
>
> Signed-off-by: Hailong Fan <hailong.fan@mediatek.com>
> ---
> Resend since some server reject.
> ---
>  drivers/pinctrl/mediatek/mtk-eint.c | 13 +++++++++++--
>  1 file changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/pinctrl/mediatek/mtk-eint.c b/drivers/pinctrl/mediatek/mtk-eint.c
> index 22736f60c16c..3acda6bb401e 100644
> --- a/drivers/pinctrl/mediatek/mtk-eint.c
> +++ b/drivers/pinctrl/mediatek/mtk-eint.c
> @@ -157,6 +157,7 @@ static void mtk_eint_ack(struct irq_data *d)
>  static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
>  {
>         struct mtk_eint *eint = irq_data_get_irq_chip_data(d);
> +       unsigned int unmask;

bool?

>         u32 mask = BIT(d->hwirq & 0x1f);
>         void __iomem *reg;
>
> @@ -173,6 +174,13 @@ static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
>         else
>                 eint->dual_edge[d->hwirq] = 0;
>
> +       if (!mtk_eint_get_mask(eint, d->hwirq)) {
> +               mtk_eint_mask(d);
> +               unmask = 1;
> +       } else {
> +               unmask = 0;
> +       }
> +
>         if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_EDGE_FALLING)) {
>                 reg = mtk_eint_get_offset(eint, d->hwirq, eint->regs->pol_clr);
>                 writel(mask, reg);
> @@ -189,8 +197,9 @@ static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
>                 writel(mask, reg);
>         }
>
> -       if (eint->dual_edge[d->hwirq])
> -               mtk_eint_flip_edge(eint, d->hwirq);

Why are you dropping this? Aren't we at risk to miss the first edge
after mtk_eint_set_type is called?

> +       mtk_eint_ack(d);
> +       if (unmask == 1)

Just `if (unmask)`

> +               mtk_eint_unmask(d);
>
>         return 0;
>  }
> --
> 2.18.0