From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Moore Date: Thu, 09 Dec 2010 07:11:27 +0100 Subject: [U-Boot] [PATCH v4 2/7] gpio: Add Multi-Function-Pin configuration driver for Marvell SoCs In-Reply-To: <4CFE713A.4050203@free.fr> References: <4CFE713A.4050203@free.fr> Message-ID: <4D00730F.1030807@free.fr> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi, Le 07/12/2010 18:39, Albert ARIBAUD a ?crit : > Le 07/12/2010 18:10, Prafulla Wadaskar a ?crit : > >>>> + val&= ~MFP_AF_MASK; >>> Do we need to do this& here? For val is only 0 here... >> This can be removed. > OTOH, with the&, this line makes no assumption about val, and thus will > work regardless of it. If the& is removed, and if later val is set to > non-zero before reaching this instruction, it will cause a bug. > > IOW, the& makes the statement more resilient. > If val really is zero then the result will always be zero :( Simply removing the & would give a different result. It would be better to remove the whole bloody line ;-) I haven't followed this thread but I suspect the original code was wrong. Cheers, Chris