Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932788Ab1CXGCj (ORCPT ); Thu, 24 Mar 2011 02:02:39 -0400 Received: from eu1sys200aog120.obsmtp.com ([207.126.144.149]:47231 "EHLO eu1sys200aog120.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755027Ab1CXGCh (ORCPT ); Thu, 24 Mar 2011 02:02:37 -0400 From: Viresh Kumar To: , , , Cc: , , , , , Viresh Kumar Subject: [PATCH] dmaengine/dw_dmac fix: dwc_scan_descriptors must compare first desc address also with llp Date: Thu, 24 Mar 2011 11:32:15 +0530 Message-ID: X-Mailer: git-send-email 1.7.2.2 MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1392 Lines: 36 dwc_scan_descriptors scans all descriptors from active_list in case transfer is not completed. It compares first_desc->lli.llp, and then all childrens of its tx_list. But it doesn't compare its own address, i.e. first_desc->txd.phys, as this is what we have initially programmed into the controller register. So this causes dma to stop and finish a transfer, which was never started. And thus fail. Signed-off-by: Viresh Kumar --- drivers/dma/dw_dmac.c | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-) diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c index b95e6d3..1bd4803 100644 --- a/drivers/dma/dw_dmac.c +++ b/drivers/dma/dw_dmac.c @@ -304,6 +304,11 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc) dev_vdbg(chan2dev(&dwc->chan), "scan_descriptors: llp=0x%x\n", llp); list_for_each_entry_safe(desc, _desc, &dwc->active_list, desc_node) { + /* check first descriptors addr */ + if (desc->txd.phys == llp) + return; + + /* check first descriptors llp */ if (desc->lli.llp == llp) /* This one is currently in progress */ return; -- 1.7.2.2 -- 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/