Re: [PATCH v2] Skip deferred request irqs for devices known to fail

[Andy Shevchenko]

On Mon, Aug 19, 2019 at 09:26:37PM +1000, Ian W MORRISON wrote:
> Patch ca876c7483b6 "gpiolib-acpi: make sure we trigger edge events at
> least once on boot" causes the MINIX family of mini PCs to fail to boot
> resulting in a "black screen".
> 
> This patch excludes MINIX devices from executing this trigger in order
> to successfully boot.

Thanks for an update.

> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Ian W MORRISON <ianwmorrison@xxxxxxxxx>
> Reviewed-by: Hans de Goede <hdegoede@xxxxxxxxxx>

> Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

Hmm... Did I really give the tag?
Too many stuff is going on, anyway, please consider more comments below.

First of all, the subject should start from "gpiolib: acpi: " prefix.

Then, Fixes tag seems to be missed.

> +/*
> + * Run deferred acpi_gpiochip_request_irqs()
> + * but exclude devices known to fail

Missed period.

> +*/

Missed leading space (the column of stars).

>  static int acpi_gpio_handle_deferred_request_irqs(void)
>  {
>  	struct acpi_gpio_chip *acpi_gpio, *tmp;
> +	const struct dmi_system_id *dmi_id;
>  
> -	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
> -	list_for_each_entry_safe(acpi_gpio, tmp,
> +	dmi_id = dmi_first_match(skip_deferred_request_irqs_table);
> +	if (dmi_id)
> +		return 0;

The idea of positive check is exactly for...

> +	else {

...getting rid of this redundant 'else' followed by unneeded level of indentation.

> +		mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
> +		list_for_each_entry_safe(acpi_gpio, tmp,
>  				 &acpi_gpio_deferred_req_irqs_list,
>  				 deferred_req_irqs_list_entry)
> -		acpi_gpiochip_request_irqs(acpi_gpio);
> +			acpi_gpiochip_request_irqs(acpi_gpio);
>  
> -	acpi_gpio_deferred_req_irqs_done = true;
> -	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
> +		acpi_gpio_deferred_req_irqs_done = true;
> +		mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
> +	}
>  
>  	return 0;
>  }

-- 
With Best Regards,
Andy Shevchenko