From patchwork Fri Oct 11 10:31:00 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Huang Shijie X-Patchwork-Id: 3022541 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 193049F1E1 for ; Fri, 11 Oct 2013 10:46:56 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id E84232016C for ; Fri, 11 Oct 2013 10:46:54 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8C57520279 for ; Fri, 11 Oct 2013 10:46:53 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VUaEp-0004a7-PI; Fri, 11 Oct 2013 10:46:31 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1VUaEk-0004HE-9C; Fri, 11 Oct 2013 10:46:26 +0000 Received: from va3ehsobe004.messaging.microsoft.com ([216.32.180.14] helo=va3outboundpool.messaging.microsoft.com) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VUaEa-0004Dg-In for linux-arm-kernel@lists.infradead.org; Fri, 11 Oct 2013 10:46:18 +0000 Received: from mail159-va3-R.bigfish.com (10.7.14.236) by VA3EHSOBE003.bigfish.com (10.7.40.23) with Microsoft SMTP Server id 14.1.225.23; Fri, 11 Oct 2013 10:45:55 +0000 Received: from mail159-va3 (localhost [127.0.0.1]) by mail159-va3-R.bigfish.com (Postfix) with ESMTP id 8CA6A3003F1; Fri, 11 Oct 2013 10:45:55 +0000 (UTC) X-Forefront-Antispam-Report: CIP:70.37.183.190; KIP:(null); UIP:(null); IPV:NLI; H:mail.freescale.net; RD:none; EFVD:NLI X-SpamScore: 3 X-BigFish: VS3(zzzz1f42h208ch1ee6h1de0h1fdah2073h1202h1e76h1d1ah1d2ah1fc6h1082kzz1de098h1de097h8275bhz2dh2a8h839hd24he5bhf0ah1288h12a5h12a9h12bdh12e5h137ah139eh13b6h1441h1504h1537h162dh1631h1758h1898h18e1h1946h19b5h1ad9h1b0ah1b2fh1fb3h1d0ch1d2eh1d3fh1dfeh1dffh1e23h1fe8h1ff5h1155h) Received: from mail159-va3 (localhost.localdomain [127.0.0.1]) by mail159-va3 (MessageSwitch) id 1381488353635806_30001; Fri, 11 Oct 2013 10:45:53 +0000 (UTC) Received: from VA3EHSMHS028.bigfish.com (unknown [10.7.14.240]) by mail159-va3.bigfish.com (Postfix) with ESMTP id 8A5DE4E005D; Fri, 11 Oct 2013 10:45:53 +0000 (UTC) Received: from mail.freescale.net (70.37.183.190) by VA3EHSMHS028.bigfish.com (10.7.99.38) with Microsoft SMTP Server (TLS) id 14.16.227.3; Fri, 11 Oct 2013 10:45:53 +0000 Received: from az84smr01.freescale.net (10.64.34.197) by 039-SN1MMR1-001.039d.mgd.msft.net (10.84.1.13) with Microsoft SMTP Server (TLS) id 14.3.158.2; Fri, 11 Oct 2013 10:45:52 +0000 Received: from shlinux2.ap.freescale.net (shlinux2.ap.freescale.net [10.192.224.44]) by az84smr01.freescale.net (8.14.3/8.14.0) with ESMTP id r9BAjhBH018398; Fri, 11 Oct 2013 03:45:50 -0700 From: Huang Shijie To: Subject: [PATCH 3/4] serial: imx: fix the wrong number of scatterlist entries when xmit->head is 0 Date: Fri, 11 Oct 2013 18:31:00 +0800 Message-ID: <1381487461-12850-4-git-send-email-b32955@freescale.com> X-Mailer: git-send-email 1.7.2.rc3 In-Reply-To: <1381487461-12850-1-git-send-email-b32955@freescale.com> References: <1381487461-12850-1-git-send-email-b32955@freescale.com> MIME-Version: 1.0 X-OriginatorOrg: freescale.com X-FOPE-CONNECTOR: Id%0$Dn%*$RO%0$TLS%0$FQDN%$TlsDn% X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20131011_064616_831266_983606B3 X-CRM114-Status: GOOD ( 12.13 ) X-Spam-Score: -2.6 (--) Cc: Huang Shijie , shawn.guo@linaro.org, linux-arm-kernel@lists.infradead.org, linux-serial@vger.kernel.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When the (xmit->tail > xmit->head) is true and the xmit->head is 0, we only need one DMA scatterlist in actually. Current code uses two DMA scatterlists in this case, this is obviously wrong. This patch fixes it. Signed-off-by: Huang Shijie --- drivers/tty/serial/imx.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index c6c3b16..cadf7e5 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -532,7 +532,7 @@ static void dma_tx_work(struct work_struct *w) return; } - if (xmit->tail > xmit->head) { + if (xmit->tail > xmit->head && xmit->head > 0) { sport->dma_tx_nents = 2; sg_init_table(sgl, 2); sg_set_buf(sgl, xmit->buf + xmit->tail,