From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759152AbXGJPsp (ORCPT ); Tue, 10 Jul 2007 11:48:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754259AbXGJPsi (ORCPT ); Tue, 10 Jul 2007 11:48:38 -0400 Received: from 81-174-11-161.static.ngi.it ([81.174.11.161]:47704 "EHLO mail.enneenne.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753913AbXGJPsh (ORCPT ); Tue, 10 Jul 2007 11:48:37 -0400 Date: Tue, 10 Jul 2007 17:49:35 +0200 From: Rodolfo Giometti To: Andrew Morton Cc: David Brownell , linux-usb-devel@lists.sourceforge.net, linux-arm-kernel@lists.arm.linux.org.uk, linux-kernel@vger.kernel.org, Li Yang-r58472 Message-ID: <20070710154935.GA3445@enneenne.com> References: <20070628103619.GW13886@enneenne.com> <989B956029373F45A0B8AF0297081890D834FA@zch01exm26.fsl.freescale.net> <20070628141205.GA13886@enneenne.com> <20070628142949.02ca9eab.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070628142949.02ca9eab.akpm@linux-foundation.org> Organization: GNU/Linux Device Drivers, Embedded Systems and Courses X-PGP-Key: gpg --keyserver keyserver.linux.it --recv-keys D25A5633 User-Agent: Mutt/1.5.16 (2007-06-11) X-SA-Exim-Connect-IP: 192.168.32.1 X-SA-Exim-Mail-From: giometti@enneenne.com Subject: Re: [PATCH] PXA27x UDC driver. X-SA-Exim-Version: 4.2 (built Thu, 03 Mar 2005 10:44:12 +0100) X-SA-Exim-Scanned: Yes (on mail.enneenne.com) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 28, 2007 at 02:29:49PM -0700, Andrew Morton wrote: > > > > + > > +static int > > +write_packet(volatile u32 * uddr, struct pxa27x_request *req, unsigned max) > > Please review Documentation/volatile-considered-harmful.txt The attibute volatile here is necessary in order to avoid getting the following warnings from the compiler: CC drivers/usb/gadget/pxa27x_udc.o drivers/usb/gadget/pxa27x_udc.c: In function `write_ep0_fifo': drivers/usb/gadget/pxa27x_udc.c:512: warning: passing arg 1 of `write_packet' discards qualifiers from pointer target type drivers/usb/gadget/pxa27x_udc.c: In function `pxa27x_ep_alloc': drivers/usb/gadget/pxa27x_udc.c:1206: warning: assignment discards qualifiers from pointer target type drivers/usb/gadget/pxa27x_udc.c:1207: warning: assignment discards qualifiers from pointer target type drivers/usb/gadget/pxa27x_udc.c:1208: warning: assignment discards qualifiers from pointer target type drivers/usb/gadget/pxa27x_udc.c:1209: warning: assignment discards qualifiers from pointer target type drivers/usb/gadget/pxa27x_udc.c: At top level: drivers/usb/gadget/pxa27x_udc.c:2159: warning: initialization discards qualifiers from pointer target type drivers/usb/gadget/pxa27x_udc.c:2160: warning: initialization discards qualifiers from pointer target type This because the variables reg_* are assigned as: .reg_udccsr = &UDCCSR0 where UDCCSR0 are defined as: #define UDCCSR0 __REG(0x40600100) /* UDC Control/Status register - Endpoint 0 */ and: define __REG(x) (*((volatile u32 *)io_p2v(x))) Do you know how I can resolve this? Thanks in advance, Rodolfo -- GNU/Linux Solutions e-mail: giometti@enneenne.com Linux Device Driver giometti@gnudd.com Embedded Systems giometti@linux.it UNIX programming phone: +39 349 2432127