From patchwork Fri Jan 29 01:17:23 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamal Mostafa X-Patchwork-Id: 575291 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 20CCB14017E; Fri, 29 Jan 2016 12:33:27 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1aOxwB-0004Fk-RH; Fri, 29 Jan 2016 01:33:23 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1aOxlN-0006Dd-Rr for kernel-team@lists.ubuntu.com; Fri, 29 Jan 2016 01:22:13 +0000 Received: from 1.general.kamal.us.vpn ([10.172.68.52] helo=fourier) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.76) (envelope-from ) id 1aOxlN-0005K3-06; Fri, 29 Jan 2016 01:22:13 +0000 Received: from kamal by fourier with local (Exim 4.82) (envelope-from ) id 1aOxlK-0004pr-4Y; Thu, 28 Jan 2016 17:22:10 -0800 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Subject: [PATCH 3.19.y-ckt 105/210] dmaengine: dw: fix cyclic transfer setup Date: Thu, 28 Jan 2016 17:17:23 -0800 Message-Id: <1454030348-17736-106-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1454030348-17736-1-git-send-email-kamal@canonical.com> References: <1454030348-17736-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Cc: Vinod Koul , Kamal Mostafa , Mans Rullgard X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com 3.19.8-ckt14 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: Mans Rullgard commit df3bb8a0e619d501cd13334c3e0586edcdcbc716 upstream. Commit 61e183f83069 ("dmaengine/dw_dmac: Reconfigure interrupt and chan_cfg register on resume") moved some channel initialisation to a new function which must be called before starting a transfer. This updates dw_dma_cyclic_start() to use dwc_dostart() like the other modes, thus ensuring dwc_initialize() gets called and removing some code duplication. Fixes: 61e183f83069 ("dmaengine/dw_dmac: Reconfigure interrupt and chan_cfg register on resume") Signed-off-by: Mans Rullgard Reviewed-by: Viresh Kumar Signed-off-by: Vinod Koul [ kamal: backport to 3.19-stable: context ] Signed-off-by: Kamal Mostafa --- drivers/dma/dw/core.c | 22 +--------------------- 1 file changed, 1 insertion(+), 21 deletions(-) diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c index 1383c73..c90f63b 100644 --- a/drivers/dma/dw/core.c +++ b/drivers/dma/dw/core.c @@ -1238,7 +1238,6 @@ static void dwc_free_chan_resources(struct dma_chan *chan) int dw_dma_cyclic_start(struct dma_chan *chan) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); - struct dw_dma *dw = to_dw_dma(dwc->chan.device); unsigned long flags; if (!test_bit(DW_DMA_IS_CYCLIC, &dwc->flags)) { @@ -1247,26 +1246,7 @@ int dw_dma_cyclic_start(struct dma_chan *chan) } spin_lock_irqsave(&dwc->lock, flags); - - /* Assert channel is idle */ - if (dma_readl(dw, CH_EN) & dwc->mask) { - dev_err(chan2dev(&dwc->chan), - "BUG: Attempted to start non-idle channel\n"); - dwc_dump_chan_regs(dwc); - spin_unlock_irqrestore(&dwc->lock, flags); - return -EBUSY; - } - - dma_writel(dw, CLEAR.ERROR, dwc->mask); - dma_writel(dw, CLEAR.XFER, dwc->mask); - - /* Setup DMAC channel registers */ - channel_writel(dwc, LLP, dwc->cdesc->desc[0]->txd.phys); - channel_writel(dwc, CTL_LO, DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN); - channel_writel(dwc, CTL_HI, 0); - - channel_set_bit(dw, CH_EN, dwc->mask); - + dwc_dostart(dwc, dwc->cdesc->desc[0]); spin_unlock_irqrestore(&dwc->lock, flags); return 0;