Re: [PATCH] genirq: Only call irq_ack if implemented by chip

From: Thomas Gleixner <tglx@linutronix.de>
To: Adrian-Ken Rueegsegger <ken@codelabs.ch>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] genirq: Only call irq_ack if implemented by chip
Date: Tue, 14 Apr 2015 20:00:44 +0200 (CEST)	[thread overview]
Message-ID: <alpine.DEB.2.11.1504141959430.3845@nanos> (raw)
In-Reply-To: <1429007347-7167-1-git-send-email-ken@codelabs.ch>

On Tue, 14 Apr 2015, Adrian-Ken Rueegsegger wrote:
> Restore the check if an IRQ chip implements the irq_ack function prior
> to its invocation. Commit 22a49163e90d ("genirq: Provide compat handling
> for chip->ack()") removed the check from handle_edge_irq while keeping
> the check in other call paths.

How's an edge triggered interrupt without ack supposed to work?

You are missing to describe which problem you solve.

Thanks,

	tglx

> Signed-off-by: Adrian-Ken Rueegsegger <ken@codelabs.ch>
> ---
>  kernel/irq/chip.c |    3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
> index eb9a4ea..3889b02 100644
> --- a/kernel/irq/chip.c
> +++ b/kernel/irq/chip.c
> @@ -586,7 +586,8 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc)
>  	kstat_incr_irqs_this_cpu(irq, desc);
>  
>  	/* Start handling the irq */
> -	desc->irq_data.chip->irq_ack(&desc->irq_data);
> +	if (desc->irq_data.chip->irq_ack)
> +		desc->irq_data.chip->irq_ack(&desc->irq_data);
>  
>  	do {
>  		if (unlikely(!desc->action)) {
> -- 
> 1.7.10.4
> 
> 