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From:   Andy Shevchenko <andy.shevchenko@gmail.com>
Date:   Thu, 17 Sep 2020 16:46:45 +0300
Message-ID: <CAHp75VeWq_GzJ_yZag2yceuUDqPiMRWEa4XNYT5uPwXCzrsb7g@mail.gmail.com>
Subject: Re: [PATCH v7 14/34] i2c: tegra: Clean up probe function
To:     Thierry Reding <thierry.reding@gmail.com>
Cc:     Dmitry Osipenko <digetx@gmail.com>,
        Jonathan Hunter <jonathanh@nvidia.com>,
        Laxman Dewangan <ldewangan@nvidia.com>,
        Wolfram Sang <wsa@the-dreams.de>,
        =?UTF-8?B?TWljaGHFgiBNaXJvc8WCYXc=?= <mirq-linux@rere.qmqm.pl>,
        linux-i2c <linux-i2c@vger.kernel.org>,
        linux-tegra@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Thu, Sep 17, 2020 at 3:37 PM Thierry Reding <thierry.reding@gmail.com> wrote:
> On Wed, Sep 09, 2020 at 01:39:46AM +0300, Dmitry Osipenko wrote:

...

> > +     ret = devm_request_irq(&pdev->dev, i2c_dev->irq, tegra_i2c_isr,
> > +                            IRQF_NO_SUSPEND, dev_name(&pdev->dev),
> > +                            i2c_dev);
> > +     if (ret)
> > +             return ret;
>
> Is it safe to install the interrupt handler at this point? What if,
> perhaps because some bootloader didn't properly quiesce the I2C
> controller, an interrupt triggers immediately after this?

It\s easy to check with debug shared IRQ, but here IRQ is not shared...
So, with a hack into the code and enabled debug it will be achievable to test.

And you probably meant that IRQ triggers *before* the handler is in place?

-- 
With Best Regards,
Andy Shevchenko