From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751458Ab3LJBBg (ORCPT ); Mon, 9 Dec 2013 20:01:36 -0500 Received: from shards.monkeyblade.net ([149.20.54.216]:44675 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750790Ab3LJBBd (ORCPT ); Mon, 9 Dec 2013 20:01:33 -0500 Date: Mon, 09 Dec 2013 20:01:31 -0500 (EST) Message-Id: <20131209.200131.1376169274733452706.davem@davemloft.net> To: freddy@asix.com.tw Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, louis@asix.com.tw, allan@asix.com.tw Subject: Re: [PATCH 1/1] AX88179_178A: Enable the hardware pseudo header in case of the NET_IP_ALIGN equals 0 From: David Miller In-Reply-To: <1386323898-2246-1-git-send-email-freddy@asix.com.tw> References: <1386323898-2246-1-git-send-email-freddy@asix.com.tw> X-Mailer: Mew version 6.5 on Emacs 24.1 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.1 (shards.monkeyblade.net [0.0.0.0]); Mon, 09 Dec 2013 17:01:33 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: freddy@asix.com.tw Date: Fri, 6 Dec 2013 17:58:18 +0800 > From: Freddy Xin > > The AX88179_178A has a hardware feature that it can insert a 2-bytes pseudo > header in front of each received frame by setting the AX_RX_CTL_IPE bit. > This feature is used to let the IP header be aligned on a doubleword-aligned address, > but the NET_IP_ALIGN may equals to 2 and the __netdev_alloc_skb_ip_align in USBNET will > reserve 2 bytes also, so in this case the driver shouldn't enable this bit. > > This patch modifies the driver to set AX_RX_CTL_IPE just in case of the NET_IP_ALIGN equals 0. > > Signed-off-by: Freddy Xin Please avoid larger than 80 column lines in your commit messages, people use text-only tools to viee these. Next, it makes no sense to restrict your change to NET_IP_ALIGN==0 Simply handle any case, by undoing the reservation if it's getting in the way. If there isn't an appropriate helper for this, add one.