Re: [PATCH v2 1/1] gpio: mlxbf3: Support shutdown() function

[Andy Shevchenko <andy.shevchenko@xxxxxxxxx>]

On Tue, Jun 11, 2024 at 8:15 PM Asmaa Mnebhi <asmaa@xxxxxxxxxx> wrote:
>
> During Linux graceful reboot, the GPIO interrupts are not disabled.
> Since the drivers are not removed during graceful reboot,
> the logic to call mlxbf3_gpio_irq_disable() is not triggered.
> Interrupts that remain enabled can cause issues on subsequent boots.
>
> For example, the mlxbf-gige driver contains PHY logic to bring up the link.
> If the gpio-mlxbf3 driver loads first, the mlxbf-gige driver
> will use a GPIO interrupt to bring up the link.
> Otherwise, it will use polling.
> The next time Linux boots and loads the drivers in this order, we encounter the issue:
> - mlxbf-gige loads first and uses polling while the GPIO10
>   interrupt is still enabled from the previous boot. So if
>   the interrupt triggers, there is nothing to clear it.
> - gpio-mlxbf3 loads.
> - i2c-mlxbf loads. The interrupt doesn't trigger for I2C
>   because it is shared with the GPIO interrupt line which
>   was not cleared.
>
> The solution is to add a shutdown function to the GPIO driver to clear and disable
> all interrupts. Also clear the interrupt after disabling it in mlxbf3_gpio_irq_disable().

LGTM, FWIW,
Reviewed-by: Andy Shevchenko <andy@xxxxxxxxxx>

-- 
With Best Regards,
Andy Shevchenko