From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1752729AbbBXACq (ORCPT <rfc822;w@1wt.eu>);
	Mon, 23 Feb 2015 19:02:46 -0500
Received: from v094114.home.net.pl ([79.96.170.134]:64378 "HELO
	v094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with SMTP id S1751861AbbBXACp (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Mon, 23 Feb 2015 19:02:45 -0500
From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: Mark Rutland <mark.rutland@arm.com>, Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        Boris Brezillon <boris.brezillon@free-electrons.com>,
        Ian Campbell <ian.campbell@citrix.com>,
        Jonathan Corbet <corbet@lwn.net>,
        "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Linux PM list <linux-pm@vger.kernel.org>
Subject: Re: [PATCH] genirq: better describe IRQF_NO_SUSPEND semantics
Date: Tue, 24 Feb 2015 01:26:05 +0100
Message-ID: <3607139.EdDhxoz0si@vostro.rjw.lan>
User-Agent: KMail/4.11.5 (Linux/3.19.0+; KDE/4.11.5; x86_64; ; )
In-Reply-To: <1424444026-31231-1-git-send-email-mark.rutland@arm.com>
References: <1424444026-31231-1-git-send-email-mark.rutland@arm.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 7Bit
Content-Type: text/plain; charset="utf-8"
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Friday, February 20, 2015 02:53:46 PM Mark Rutland wrote:
> The IRQF_NO_SUSPEND flag is intended to be used for interrupts required
> to be enabled during the suspend-resume cycle. This mostly consists of
> IPIs and timer interrupts, potentially including chained irqchip
> interrupts if these are necessary to handle timers or IPIs. If an
> interrupt does not fall into one of the aforementioned categories,
> requesting it with IRQF_NO_SUSPEND is likely incorrect.
> 
> Using IRQF_NO_SUSPEND does not guarantee that the interrupt can wake the
> system from a suspended state. For an interrupt to be able to trigger a
> wakeup, it may be necessary to program various components of the system.
> In these cases it is necessary to use {enable,disabled}_irq_wake.
> 
> Unfortunately, several drivers assume that IRQF_NO_SUSPEND ensures that
> an IRQ can wake up the system, and the documentation can be read
> ambiguously w.r.t. this property.
> 
> This patch updates the documentation regarding IRQF_NO_SUSPEND to make
> this caveat explicit, hopefully making future misuse rarer. Cleanup of
> existing misuse will occur as part of later patch series.
> 
> Cc: Boris Brezillon <boris.brezillon@free-electrons.com>
> Cc: Ian Campbell <ian.campbell@citrix.com>
> Cc: Jonathan Corbet <corbet@lwn.net>
> Cc: Peter Zijlstra <peterz@infradead.org>
> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Signed-off-by: Mark Rutland <mark.rutland@arm.com>

Applied to linux-pm.git/linux-next, thanks!

Peter, please let me know if you don't want this to go it.

Rafael