From patchwork Mon Jul 29 13:29:51 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joel Fernandes X-Patchwork-Id: 2834997 Return-Path: X-Original-To: patchwork-davinci@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 99AA89F9D9 for ; Mon, 29 Jul 2013 13:33:29 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 73BCC2020E for ; Mon, 29 Jul 2013 13:33:28 +0000 (UTC) Received: from devils.ext.ti.com (devils.ext.ti.com [198.47.26.153]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1710820249 for ; Mon, 29 Jul 2013 13:33:26 +0000 (UTC) Received: from dlelxv90.itg.ti.com ([172.17.2.17]) by devils.ext.ti.com (8.13.7/8.13.7) with ESMTP id r6TDWJsS024310; Mon, 29 Jul 2013 08:32:19 -0500 Received: from DFLE72.ent.ti.com (dfle72.ent.ti.com [128.247.5.109]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id r6TDWIpK013405; Mon, 29 Jul 2013 08:32:18 -0500 Received: from dlelxv24.itg.ti.com (172.17.1.199) by DFLE72.ent.ti.com (128.247.5.109) with Microsoft SMTP Server id 14.2.342.3; Mon, 29 Jul 2013 08:32:18 -0500 Received: from linux.omap.com (dlelxs01.itg.ti.com [157.170.227.31]) by dlelxv24.itg.ti.com (8.13.8/8.13.8) with ESMTP id r6TDWIYW012460; Mon, 29 Jul 2013 08:32:18 -0500 Received: from linux.omap.com (localhost [127.0.0.1]) by linux.omap.com (Postfix) with ESMTP id 8A92280628; Mon, 29 Jul 2013 08:32:18 -0500 (CDT) X-Original-To: davinci-linux-open-source@linux.davincidsp.com Delivered-To: davinci-linux-open-source@linux.davincidsp.com Received: from dlelxv90.itg.ti.com (dlelxv90.itg.ti.com [172.17.2.17]) by linux.omap.com (Postfix) with ESMTP id CDBB38062C for ; Mon, 29 Jul 2013 08:30:17 -0500 (CDT) Received: from DFLE72.ent.ti.com (dfle72.ent.ti.com [128.247.5.109]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id r6TDUFOd007833; Mon, 29 Jul 2013 08:30:15 -0500 Received: from dlelxv22.itg.ti.com (172.17.1.197) by DFLE72.ent.ti.com (128.247.5.109) with Microsoft SMTP Server id 14.2.342.3; Mon, 29 Jul 2013 08:30:15 -0500 Received: from joel-laptop.itg.ti.com (h0-79.vpn.ti.com [172.24.0.79]) by dlelxv22.itg.ti.com (8.13.8/8.13.8) with ESMTP id r6TDTuP3008221; Mon, 29 Jul 2013 08:30:14 -0500 From: Joel Fernandes To: Tony Lindgren , Sekhar Nori , Santosh Shilimkar , Sricharan R , Rajendra Nayak , Lokesh Vutla , Matt Porter , Grant Likely , Rob Herring , Vinod Koul , Dan Williams , Mark Brown , Benoit Cousson , Russell King , Arnd Bergmann , Olof Johansson , Balaji TK , Gururaja Hebbar , Chris Ball , Jason Kridner Subject: [PATCH 5/9] dma: edma: Leave linked to Null slot instead of DUMMY slot Date: Mon, 29 Jul 2013 08:29:51 -0500 Message-ID: <1375104595-16018-6-git-send-email-joelf@ti.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1375104595-16018-1-git-send-email-joelf@ti.com> References: <1375104595-16018-1-git-send-email-joelf@ti.com> MIME-Version: 1.0 CC: Linux DaVinci Kernel List , Joel Fernandes , Linux MMC List , Linux Kernel Mailing List , Linux OMAP List , Linux ARM Kernel List X-BeenThere: davinci-linux-open-source@linux.davincidsp.com X-Mailman-Version: 2.1.12 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: Errors-To: davinci-linux-open-source-bounces@linux.davincidsp.com X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, 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 Dummy slot has been used as a way for missed-events not to be reported as missing. This has been particularly troublesome for cases where we might want to temporarily pause all incoming events. For EDMA DMAC, there is no way to do any such pausing of events as the occurence of the "next" event is not software controlled. Using "edma_pause" in IRQ handlers doesn't help as by then the event in concern from the slave is already missed. Linking a dummy slot, is seen to absorb these events which we didn't want to miss. So we don't link to dummy, but instead leave it linked to NULL set, allow an error condition and detect the channel that missed it. Signed-off-by: Joel Fernandes --- drivers/dma/edma.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c index aa4989f..1eda5cc 100644 --- a/drivers/dma/edma.c +++ b/drivers/dma/edma.c @@ -159,9 +159,6 @@ static void edma_execute(struct edma_chan *echan) /* Link to the previous slot if not the last set */ if (i != (total_process - 1)) edma_link(echan->slot[i], echan->slot[i+1]); - /* Final pset links to the dummy pset */ - else - edma_link(echan->slot[i], echan->ecc->dummy_slot); } edesc->total_processed += total_process;