From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C8752C28CC1 for ; Sat, 1 Jun 2019 21:41:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9420C27798 for ; Sat, 1 Jun 2019 21:41:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=lunn.ch header.i=@lunn.ch header.b="nSPbktMj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726496AbfFAVgU (ORCPT ); Sat, 1 Jun 2019 17:36:20 -0400 Received: from vps0.lunn.ch ([185.16.172.187]:47888 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726210AbfFAVgU (ORCPT ); Sat, 1 Jun 2019 17:36:20 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lunn.ch; s=20171124; h=In-Reply-To:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=QGXnux2WNbpolyXTp8iNgupCVhUGsbikq94gTD1u7PU=; b=nSPbktMjkl+NdGQtUop1T+zRJ3 9HwQf5BH5GhxKRxciJsrFMjWoJNMDHH9XagbNFJLNeHuNfQvf8VD64ev1P7XW7VfFtvjSOOp1/XQg 8dSvLEafeaxgSDSkemv2xz38qTcT2yuGWzByeYAojNSyCTh6f35Nk+qHndSzdaO/jY9k=; Received: from andrew by vps0.lunn.ch with local (Exim 4.89) (envelope-from ) id 1hXBfh-0006hg-FS; Sat, 01 Jun 2019 23:36:13 +0200 Date: Sat, 1 Jun 2019 23:36:13 +0200 From: Andrew Lunn To: Vladimir Oltean Cc: Florian Fainelli , Vivien Didelot , "David S. Miller" , netdev Subject: Re: [PATCH net 1/2] net: dsa: sja1105: Force a negative value for enum sja1105_speed_t Message-ID: <20190601213613.GD19081@lunn.ch> References: <20190601103735.27506-1-olteanv@gmail.com> <20190601103735.27506-2-olteanv@gmail.com> <20190601160356.GB19081@lunn.ch> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Sat, Jun 01, 2019 at 11:30:16PM +0300, Vladimir Oltean wrote: > On Sat, 1 Jun 2019 at 19:03, Andrew Lunn wrote: > > > > On Sat, Jun 01, 2019 at 01:37:34PM +0300, Vladimir Oltean wrote: > > > The code in sja1105_adjust_port_config relies on the fact that an > > > invalid link speed is detected by sja1105_get_speed_cfg and returned as > > > -EINVAL. However storing this into an enum that only has positive > > > members will cast it into an unsigned value, and it will miss the > > > negative check. > > > > > > So make the -EINVAL value part of the enum, so that it is stored as a > > > signed number and passes the negative check. > > > > > > Fixes: 8aa9ebccae87 ("net: dsa: Introduce driver for NXP SJA1105 5-port L2 switch") > > > Signed-off-by: Vladimir Oltean > > > > Hi Vladimir > > > > It seems like just using a switch statement would be simpler, and more > > likely to be correct. And it would avoid adding SJA1105_SPEED_INVALID > > = -EINVAL which feels hackish. > > > > Andrew > > Hi Andrew, > > You mean I should completely remove the sja1105_get_speed_cfg function? > I suppose I can do that, I'm only using it in one place. I think it is often better to use simple, obviously correct code. This seems to be one example. Andrew