From patchwork Thu Nov 26 15:19:12 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andy Shevchenko X-Patchwork-Id: 7707631 Return-Path: X-Original-To: patchwork-linux-acpi@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 637679F2EC for ; Thu, 26 Nov 2015 15:21:21 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 994DA20673 for ; Thu, 26 Nov 2015 15:21:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C2D1920666 for ; Thu, 26 Nov 2015 15:21:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752217AbbKZPU6 (ORCPT ); Thu, 26 Nov 2015 10:20:58 -0500 Received: from mga02.intel.com ([134.134.136.20]:53900 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751646AbbKZPTW (ORCPT ); Thu, 26 Nov 2015 10:19:22 -0500 Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga101.jf.intel.com with ESMTP; 26 Nov 2015 07:19:21 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,347,1444719600"; d="scan'208";a="847643355" Received: from black.fi.intel.com ([10.237.72.93]) by fmsmga001.fm.intel.com with ESMTP; 26 Nov 2015 07:19:19 -0800 Received: by black.fi.intel.com (Postfix, from userid 1003) id 2815D168; Thu, 26 Nov 2015 17:19:15 +0200 (EET) From: Andy Shevchenko To: "Rafael J. Wysocki" , linux-acpi@vger.kernel.org, Vinod Koul , dmaengine@vger.kernel.org, Thomas Gleixner , Greg Kroah-Hartman , Jarkko Nikula , linux-kernel@vger.kernel.org, Mika Westerberg Cc: Andy Shevchenko Subject: [PATCH v2 6/7] dmaengine: dw: return immediately from IRQ when DMA isn't in use Date: Thu, 26 Nov 2015 17:19:12 +0200 Message-Id: <1448551153-84719-7-git-send-email-andriy.shevchenko@linux.intel.com> X-Mailer: git-send-email 2.6.2 In-Reply-To: <1448551153-84719-1-git-send-email-andriy.shevchenko@linux.intel.com> References: <1448551153-84719-1-git-send-email-andriy.shevchenko@linux.intel.com> Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org X-Spam-Status: No, score=-7.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, 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 There is no need to bother the hardware when all channels are idle. We have not to get any interrupts. Signed-off-by: Andy Shevchenko --- drivers/dma/dw/core.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c index 7067b6d..8b20930 100644 --- a/drivers/dma/dw/core.c +++ b/drivers/dma/dw/core.c @@ -622,12 +622,17 @@ static void dw_dma_tasklet(unsigned long data) static irqreturn_t dw_dma_interrupt(int irq, void *dev_id) { struct dw_dma *dw = dev_id; - u32 status = dma_readl(dw, STATUS_INT); + u32 status; + /* Check if we have any interrupt from the DMAC which is not in use */ + if (!dw->in_use) + return IRQ_NONE; + + status = dma_readl(dw, STATUS_INT); dev_vdbg(dw->dma.dev, "%s: status=0x%x\n", __func__, status); /* Check if we have any interrupt from the DMAC */ - if (!status || !dw->in_use) + if (!status) return IRQ_NONE; /*