Re: [PATCH v2 07/13] i2c: acpi: Use ACPI wake capability bit to set wake_irq

From: Andy Shevchenko
Date: Tue Sep 13 2022 - 14:17:26 EST


On Mon, Sep 12, 2022 at 04:13:11PM -0600, Raul E Rangel wrote:
> Device tree already has a mechanism to pass the wake_irq. It does this
> by looking for the wakeup-source property and setting the
> I2C_CLIENT_WAKE flag. This CL adds the ACPI equivalent. It uses the
> ACPI interrupt wake flag to determine if the interrupt can be used to
> wake the system. Previously the i2c drivers had to make assumptions and
> blindly enable the wake IRQ. This can cause spurious wake events. e.g.,
> If there is a device with an Active Low interrupt and the device gets
> powered off while suspending, the interrupt line will go low since it's
> no longer powered and wakes the system. For this reason we should
> respect the board designers wishes and honor the wake bit defined on the
> interrupt.

...

> + if (irq > 0 && acpi_wake_capable)
> + client->flags |= I2C_CLIENT_WAKE;

Why do we need a parameter and can't simply set this flag inside the callee?

--
With Best Regards,
Andy Shevchenko