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Date:   Fri, 19 Mar 2021 14:23:29 +0100
From:   Andrew Lunn <andrew@lunn.ch>
To:     Asmaa Mnebhi <asmaa@nvidia.com>
Cc:     "linus.walleij@linaro.org" <linus.walleij@linaro.org>,
        "bgolaszewski@baylibre.com" <bgolaszewski@baylibre.com>,
        David Thompson <davthompson@nvidia.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-gpio@vger.kernel.org" <linux-gpio@vger.kernel.org>
Subject: Re: [PATCH v1 1/1] gpio: Support interrupts in gpio-mlxbf2.c
Message-ID: <YFSl0Vrh04etK28J@lunn.ch>
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> We cannot really pass it through the ACPI table because the ACPI
> table is common to all BlueField-2 boards.  And each board may have
> a different GPIO pin associated with a particular function. This is
> why we use ACPI properties instead of GpioInt(). So that the
> bootloader can change the GPIO pin value based on the board id
> detected at boot time.

That sounds very broken.

ACPI describes the hardware. If the hardware is different, you need
different ACPI. And i assume the ACPI spec says GpioInt() is the
correct way to do this, and does not say you can hack around
limitations of your bootloader using properties?

	    Andrew