linux-kernel - Re: [PATCH] pinctrl: mediatek: Fix trigger type setting follow for unexpected interrupt

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CANMq1KCfBy9dRELP-hMjY5FraachcRGHEC9mmaMjJCLQzdu+ZA@mail.gmail.com>
Date:   Mon, 25 Jan 2021 11:24:16 +0800
From:   Nicolas Boichat <drinkcat@...omium.org>
To:     Hailong Fan <hailong.fan@...iatek.com>
Cc:     Sean Wang <sean.wang@...nel.org>,
        Linus Walleij <linus.walleij@...aro.org>,
        Matthias Brugger <matthias.bgg@...il.com>,
        "moderated list:ARM/Mediatek SoC support" 
        <linux-mediatek@...ts.infradead.org>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@...r.kernel.org>,
        linux-arm Mailing List <linux-arm-kernel@...ts.infradead.org>,
        lkml <linux-kernel@...r.kernel.org>, youlin.pei@...iatek.com,
        srv_heupstream <srv_heupstream@...iatek.com>,
        Chen-Tsung Hsieh <chentsung@...omium.org>,
        gtk_pangao@...iatek.com, Hanks Chen <hanks.chen@...iatek.com>,
        Yong Wu <yong.wu@...iatek.com>
Subject: Re: [PATCH] pinctrl: mediatek: Fix trigger type setting follow for
 unexpected interrupt

On Mon, Jan 25, 2021 at 11:15 AM Hailong Fan <hailong.fan@...iatek.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.

I'd add a short note about why you remove mtk_eint_flip_edge, that is,
because mtk_eint_unmask already calls it.

>
> Signed-off-by: Hailong Fan <hailong.fan@...iatek.com>
> ---
> [V2]
> ---
>  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..0042f32c7e7e 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);
> +       bool unmasked;

Well, this is true if the interrupt has been masked (or, equivalently,
if we need to unmask it later).

So I think either "masked" or "unmask" are better as variable names.

>         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);
> +               unmasked = true;
> +       } else {
> +               unmasked = false;
> +       }
> +
>         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);
> +       mtk_eint_ack(d);
> +       if (unmasked)
> +               mtk_eint_unmask(d);
>
>         return 0;
>  }
> --
> 2.18.0