linux-kernel - Re: [PATCH v4 2/2] Input: gpio-keys - Add system suspend support for dedicated wakeirqs

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Date:   Fri, 24 Nov 2023 20:50:31 -0800
From:   Dmitry Torokhov <dmitry.torokhov@...il.com>
To:     Tony Lindgren <tony@...mide.com>
Cc:     Rob Herring <robh+dt@...nel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>,
        Conor Dooley <conor+dt@...nel.org>,
        linux-input@...r.kernel.org, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        Rob Herring <robh@...nel.org>, Dhruva Gole <d-gole@...com>
Subject: Re: [PATCH v4 2/2] Input: gpio-keys - Add system suspend support for
 dedicated wakeirqs

Hi Tony,

On Fri, Nov 24, 2023 at 10:32:41AM +0200, Tony Lindgren wrote:
> +	/*
> +	 * Wakeirq shares the handler with the main interrupt, it's only
> +	 * active during system suspend. See gpio_keys_button_enable_wakeup()
> +	 * and gpio_keys_button_disable_wakeup().
> +	 */
> +	error = devm_request_any_context_irq(dev, bdata->wakeirq, isr,
> +					     irqflags, wakedesc, bdata);
> +	if (error < 0) {
> +		dev_err(dev, "Unable to claim wakeirq %d; error %d\n",
> +			bdata->irq, error);
> +		return error;
> +	}
> +
> +	/*
> +	 * Disable wakeirq until suspend. IRQF_NO_AUTOEN won't work if
> +	 * IRQF_SHARED was set based on !button->can_disable.
> +	 */
> +	disable_irq_nosync(bdata->wakeirq);

Why _nosync() here and below? Is there any harm in sing the normal
variant?

Thanks.

-- 
Dmitry