From patchwork Mon Sep 21 12:26:11 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "tiffany.lin" X-Patchwork-Id: 7229561 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id F1A1ABEEC1 for ; Mon, 21 Sep 2015 12:41:30 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1B5D8207CC for ; Mon, 21 Sep 2015 12:41:30 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1CE0A20783 for ; Mon, 21 Sep 2015 12:41:29 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Ze0Go-0004T8-Ir; Mon, 21 Sep 2015 12:32:34 +0000 Received: from [210.61.82.184] (helo=mailgw02.mediatek.com) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Ze0Gm-0004Jb-5J; Mon, 21 Sep 2015 12:32:32 +0000 X-Listener-Flag: 11101 Received: from mtkhts07.mediatek.inc [(172.21.101.69)] by mailgw02.mediatek.com (envelope-from ) (mhqrelay.mediatek.com ESMTP with TLS) with ESMTP id 846516599; Mon, 21 Sep 2015 20:26:42 +0800 Received: from mtksdaap41.mediatek.inc (172.21.77.4) by mtkhts07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 14.3.181.6; Mon, 21 Sep 2015 20:26:40 +0800 From: Tiffany Lin To: Pawel Osciak , Marek Szyprowski , Kyungmin Park Subject: [RESEND PATCH] media: vb2: Fix vb2_dc_prepare do not correct sync data to device Date: Mon, 21 Sep 2015 20:26:11 +0800 Message-ID: <1442838371-21484-1-git-send-email-tiffany.lin@mediatek.com> X-Mailer: git-send-email 1.8.1.1.dirty MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150921_053232_404626_756FE48B X-CRM114-Status: GOOD ( 14.66 ) X-Spam-Score: -1.1 (-) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mauro Carvalho Chehab , linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org, Matthias Brugger , Tiffany Lin , linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD,UNPARSEABLE_RELAY autolearn=ham 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 vb2_dc_prepare use the number of SG entries dma_map_sg_attrs return. But in dma_sync_sg_for_device, it use lengths of each SG entries before dma_map_sg_attrs. dma_map_sg_attrs will concatenate SGs until dma length > dma seg bundary. sgt->nents will less than sgt->orig_nents. Using SG entries after dma_map_sg_attrs in vb2_dc_prepare will make some SGs are not sync to device. After add DMA_ATTR_SKIP_CPU_SYNC in vb2_dc_get_userptr to remove sync data to device twice. Device randomly get incorrect data because some SGs are not sync to device. Change to use number of SG entries before dma_map_sg_attrs in vb2_dc_prepare to prevent this issue. Signed-off-by: Tiffany Lin Acked-by: Sakari Ailus --- drivers/media/v4l2-core/videobuf2-dma-contig.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/media/v4l2-core/videobuf2-dma-contig.c b/drivers/media/v4l2-core/videobuf2-dma-contig.c index 2397ceb..c5d00bd 100644 --- a/drivers/media/v4l2-core/videobuf2-dma-contig.c +++ b/drivers/media/v4l2-core/videobuf2-dma-contig.c @@ -100,7 +100,7 @@ static void vb2_dc_prepare(void *buf_priv) if (!sgt || buf->db_attach) return; - dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); + dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir); } static void vb2_dc_finish(void *buf_priv) @@ -112,7 +112,7 @@ static void vb2_dc_finish(void *buf_priv) if (!sgt || buf->db_attach) return; - dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); + dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir); } /*********************************************/