From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753351AbZBHR1R (ORCPT ); Sun, 8 Feb 2009 12:27:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752404AbZBHR1D (ORCPT ); Sun, 8 Feb 2009 12:27:03 -0500 Received: from smtp115.sbc.mail.sp1.yahoo.com ([69.147.64.88]:26127 "HELO smtp115.sbc.mail.sp1.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752202AbZBHR1C (ORCPT ); Sun, 8 Feb 2009 12:27:02 -0500 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=pacbell.net; h=Received:X-YMail-OSG:X-Yahoo-Newman-Property:From:To:Subject:Date:User-Agent:Cc:References:In-Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-Disposition:Message-Id; b=hEcs0SYhYQu5WIY9sB4JqGo/ADWYxZrnLmW84I5sNF42avmgCYXVz4Rb+iPB9Ubwd5xVcIqVT+XyVFH2lRTQ88xzj8PMuh3E/I+jAjKmyAS4tjn/K6H0vEVT2yxp2+Hts7snpbFY/1pWVdM2Y/U4nWgR7gqgDi2OVRHJMlkvjiM= ; X-YMail-OSG: OemSOQcVM1n0mGkkOAswyCwF5rH3lcTnBqdn8M8FlvVT1gsx6kGervedqrGfJFtxEzqfeBE54yh3CFlt9GgBK_ykK3n6MkZa2EEZmtGvCoRfjon6taS_oH2upa0oMPwNfoSlbWYle8zwMOeojTVaBR8qYpj5gUbwYfzfin7pm1t3uQJ3WnStyGY_h6mh7P1h_UZLJASLzL2OI1aLKc4h8yi7KEx6YOwm9f1tAQ-- X-Yahoo-Newman-Property: ymail-3 From: David Brownell To: Roel Kluin Subject: Re: [PATCH] spi: limit reaches -1, tested 0 Date: Sun, 8 Feb 2009 09:26:54 -0800 User-Agent: KMail/1.9.10 Cc: spi-devel-general@lists.sourceforge.net, lkml , Andrew Morton References: <498EE9C0.3010601@gmail.com> <200902080828.49036.david-b@pacbell.net> <498F0D64.4040909@gmail.com> In-Reply-To: <498F0D64.4040909@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200902080926.56810.david-b@pacbell.net> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sunday 08 February 2009, Roel Kluin wrote: > >>> - while ((read(drv_data) == 0) && limit--); > >>> + while ((read(drv_data) == 0) && --limit); > > > > ... although I wouldn't have resisted the urge to make the > > loop body be "cpu_relax();" instead of an empty statement. > > Ok, > ---------------------------->8-------------------8<----------------------------- > With a postfix decrement limit will reach -1 rather than 0, so the warning will > not be issued. > > Signed-off-by: Roel Kluin Still: Acked-by: David Brownell > --- > diff --git a/drivers/spi/spi_imx.c b/drivers/spi/spi_imx.c > index 269a55e..15abe61 100644 > --- a/drivers/spi/spi_imx.c > +++ b/drivers/spi/spi_imx.c > @@ -779,7 +779,8 @@ static irqreturn_t interrupt_transfer(struct driver_data *drv_data) > > /* Read trailing bytes */ > limit = loops_per_jiffy << 1; > - while ((read(drv_data) == 0) && limit--); > + while ((read(drv_data) == 0) && limit--) > + cpu_relax(); > > if (limit == 0) > dev_err(&drv_data->pdev->dev, > >