From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [PATCH 15/17] i2c: omap: always return IRQ_HANDLED Date: Thu, 14 Jun 2012 12:23:23 +0100 Message-ID: <20120614112323.GD31187@n2100.arm.linux.org.uk> References: <1339669250-9183-1-git-send-email-balbi@ti.com> <1339669250-9183-16-git-send-email-balbi@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: "Shilimkar, Santosh" Cc: Felipe Balbi , Tony Lindgren , w.sang@pengutronix.de, Linux Kernel Mailing List , linux-i2c@vger.kernel.org, ben-linux@fluff.org, Linux OMAP Mailing List , Linux ARM Kernel Mailing List List-Id: linux-i2c@vger.kernel.org On Thu, Jun 14, 2012 at 04:48:56PM +0530, Shilimkar, Santosh wrote: > On Thu, Jun 14, 2012 at 3:50 PM, Felipe Balbi wrote: > > otherwise we could get our IRQ line disabled due > > to many spurious IRQs. > > > > Signed-off-by: Felipe Balbi > > --- > > =A0drivers/i2c/busses/i2c-omap.c | =A0 =A02 +- > > =A01 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c= -omap.c > > index fc5b8bc..5b78a73 100644 > > --- a/drivers/i2c/busses/i2c-omap.c > > +++ b/drivers/i2c/busses/i2c-omap.c > > @@ -1015,7 +1015,7 @@ omap_i2c_isr(int this_irq, void *dev_id) > > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0} > > =A0 =A0 =A0 =A0} while (stat); > > > > - =A0 =A0 =A0 return count ? IRQ_HANDLED : IRQ_NONE; > > + =A0 =A0 =A0 return IRQ_HANDLED; >=20 > no sure if this is correct. if you have IRQ flood and instead of _act= ually_ > handling it, if you return handled, you still have interrupt pending,= right? The point of returning IRQ_NONE is to indicate to the interrupt layer t= hat the interrupt you received was not processed by any interrupt handler, = and therefore to provide a way of preventing the system being brought to a = halt though a stuck interrupt line. So, if you do process an interrupt, you should always return IRQ_HANDLE= D even if you couldn't complete its processing (eg, because you've servic= ed it 100 times.)