[RFC 18/18] power: supply: max17040: Do not enforce (incorrect) interrupt trigger type

[Krzysztof Kozlowski]

On Thu, Dec 10, 2020 at 10:25:34PM +0100, Krzysztof Kozlowski wrote:
> Interrupt line can be configured on different hardware in different way,
> even inverted.  Therefore driver should not enforce specific trigger
> type - edge falling - but instead rely on Devicetree to configure it.
> 
> The Maxim 14577/77836 datasheets describe the interrupt line as active
> low with a requirement of acknowledge from the CPU therefore the edge
> falling is not correct.
> 
> Signed-off-by: Krzysztof Kozlowski <krzk at kernel.org>
> 
> ---
> 
> This patch should wait till DTS changes are merged, as it relies on
> proper Devicetree.
> ---
>  .../devicetree/bindings/power/supply/max17040_battery.txt       | 2 +-
>  drivers/power/supply/max17040_battery.c                         | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/power/supply/max17040_battery.txt b/Documentation/devicetree/bindings/power/supply/max17040_battery.txt
> index c802f664b508..194eb9fe574d 100644
> --- a/Documentation/devicetree/bindings/power/supply/max17040_battery.txt
> +++ b/Documentation/devicetree/bindings/power/supply/max17040_battery.txt
> @@ -39,7 +39,7 @@ Example:
>  		reg = <0x36>;
>  		maxim,alert-low-soc-level = <10>;
>  		interrupt-parent = <&gpio7>;
> -		interrupts = <2 IRQ_TYPE_EDGE_FALLING>;
> +		interrupts = <2 IRQ_TYPE_LEVEL_LOW>;
>  		wakeup-source;
>  	};
>  
> diff --git a/drivers/power/supply/max17040_battery.c b/drivers/power/supply/max17040_battery.c
> index d956c67d5155..f737de0470de 100644
> --- a/drivers/power/supply/max17040_battery.c
> +++ b/drivers/power/supply/max17040_battery.c
> @@ -367,7 +367,7 @@ static int max17040_enable_alert_irq(struct max17040_chip *chip)
>  
>  	flags = IRQF_TRIGGER_FALLING | IRQF_ONESHOT;

This has to be removed. I will fix it in v2.

Best regards,
Krzysztof


>  	ret = devm_request_threaded_irq(&client->dev, client->irq, NULL,
> -					max17040_thread_handler, flags,
> +					max17040_thread_handler, IRQF_ONESHOT,
>  					chip->battery->desc->name, chip);
>  
>  	return ret;
> -- 
> 2.25.1
>