From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755268AbcA2B43 (ORCPT ); Thu, 28 Jan 2016 20:56:29 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:33064 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752269AbcA2BWP (ORCPT ); Thu, 28 Jan 2016 20:22:15 -0500 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Mans Rullgard , Vinod Koul , Kamal Mostafa 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 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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; -- 1.9.1