Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754899Ab2EUMbp (ORCPT ); Mon, 21 May 2012 08:31:45 -0400 Received: from va3ehsobe010.messaging.microsoft.com ([216.32.180.30]:37847 "EHLO va3outboundpool.messaging.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754431Ab2EUMbo (ORCPT ); Mon, 21 May 2012 08:31:44 -0400 X-Forefront-Antispam-Report: CIP:70.37.183.190;KIP:(null);UIP:(null);IPV:NLI;H:mail.freescale.net;RD:none;EFVD:NLI X-SpamScore: 0 X-BigFish: VS0(zzzz1202hzz8275bhz2dh2a8h668h839hd24he5bhf0ah) From: Richard Zhao To: , CC: , , , , , Richard Zhao Subject: [PATCH 1/1] dma: imx-sdma: buf_tail should be initialize in prepare function Date: Mon, 21 May 2012 20:31:34 +0800 Message-ID: <1337603494-27464-1-git-send-email-richard.zhao@freescale.com> X-Mailer: git-send-email 1.7.5.4 MIME-Version: 1.0 Content-Type: text/plain X-OriginatorOrg: freescale.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1386 Lines: 50 This fix audio underrun issue. When SNDRV_PCM_TRIGGER_STOP and SNDRV_PCM_TRIGGER_START, it calls prepare again. buf_tail should be reset to zero. So move buf_tail initialization into prepare function. Signed-off-by: Richard Zhao --- drivers/dma/imx-sdma.c | 6 ++++-- 1 files changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c index a472a29..def08f7 100644 --- a/drivers/dma/imx-sdma.c +++ b/drivers/dma/imx-sdma.c @@ -814,8 +814,6 @@ static int sdma_request_channel(struct sdma_channel *sdmac) init_completion(&sdmac->done); - sdmac->buf_tail = 0; - return 0; out: @@ -924,6 +922,8 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg( sdmac->flags = 0; + sdmac->buf_tail = 0; + dev_dbg(sdma->dev, "setting up %d entries for channel %d.\n", sg_len, channel); @@ -1024,6 +1024,8 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic( sdmac->status = DMA_IN_PROGRESS; + sdmac->buf_tail = 0; + sdmac->flags |= IMX_DMA_SG_LOOP; sdmac->direction = direction; ret = sdma_load_context(sdmac); -- 1.7.5.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/