Message-ID: <4B290A57.3010705@grandegger.com>
Date: Wed, 16 Dec 2009 17:27:03 +0100
From: Wolfgang Grandegger <wg@grandegger.com>
User-Agent: Thunderbird 2.0.0.23 (X11/20090812)
MIME-Version: 1.0
To: =?ISO-8859-1?Q?Uwe_Kleine-K=F6nig?= 
	<u.kleine-koenig@pengutronix.de>
CC: linux-kernel@vger.kernel.org, David Vrabel <dvrabel@arcom.com>,
       Greg Kroah-Hartman <gregkh@suse.de>,
       Urs Thuermann <urs.thuermann@volkswagen.de>,
       Oliver Hartkopp <oliver.hartkopp@volkswagen.de>,
       "David S. Miller" <davem@davemloft.net>,
       Kurt Van Dijck <kurt.van.dijck@eia.be>, netdev@vger.kernel.org
Subject: Re: [PATCH 4/7] can/at91: don't check platform_get_irq's return value
 against zero
References: <1260979809-24811-1-git-send-email-u.kleine-koenig@pengutronix.de> <1260979809-24811-2-git-send-email-u.kleine-koenig@pengutronix.de> <1260979809-24811-3-git-send-email-u.kleine-koenig@pengutronix.de> <1260979809-24811-4-git-send-email-u.kleine-koenig@pengutronix.de>
In-Reply-To: <1260979809-24811-4-git-send-email-u.kleine-koenig@pengutronix.de>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 653
Lines: 15

Uwe Kleine-K?nig wrote:
> platform_get_irq returns -ENXIO on failure, so !irq was probably
> always true.  Better use (int)irq <= 0.  Note that a return value of
> zero is still handled as error even though this could mean irq0.

But only on ARM, which is the only platform still using the infamous
NO_IRQ (=-1). As this is a driver for ARM hardware, using irq == NO_IRQ
would make sense, though.

Wolfgang.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/