Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756900Ab3IYAX1 (ORCPT ); Tue, 24 Sep 2013 20:23:27 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:39852 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756810Ab3IYAVL (ORCPT ); Tue, 24 Sep 2013 20:21:11 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sergei Shtylyov , Guennadi Liakhovetski , Chris Ball Subject: [ 110/117] mmc: tmio_mmc_dma: fix PIO fallback on SDHI Date: Tue, 24 Sep 2013 17:19:36 -0700 Message-Id: <20130925001752.953317344@linuxfoundation.org> X-Mailer: git-send-email 1.8.4.3.gca3854a In-Reply-To: <20130925001740.833541979@linuxfoundation.org> References: <20130925001740.833541979@linuxfoundation.org> User-Agent: quilt/0.60-5.1.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2412 Lines: 68 3.11-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sergei Shtylyov commit f936f9b67b7f8c2eae01dd303a0e90bd777c4679 upstream. I'm testing SH-Mobile SDHI driver in DMA mode with a new DMA controller using 'bonnie++' and getting DMA error after which the tmio_mmc_dma.c code falls back to PIO but all commands time out after that. It turned out that the fallback code calls tmio_mmc_enable_dma() with RX/TX channels already freed and pointers to them cleared, so that the function bails out early instead of clearing the DMA bit in the CTL_DMA_ENABLE register. The regression was introduced by commit 162f43e31c5a376ec16336e5d0ac973373d54c89 (mmc: tmio: fix a deadlock). Moving tmio_mmc_enable_dma() calls to the top of the PIO fallback code in tmio_mmc_start_dma_{rx|tx}() helps. Signed-off-by: Sergei Shtylyov Acked-by: Guennadi Liakhovetski Signed-off-by: Chris Ball Signed-off-by: Greg Kroah-Hartman --- drivers/mmc/host/tmio_mmc_dma.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/mmc/host/tmio_mmc_dma.c +++ b/drivers/mmc/host/tmio_mmc_dma.c @@ -104,6 +104,7 @@ static void tmio_mmc_start_dma_rx(struct pio: if (!desc) { /* DMA failed, fall back to PIO */ + tmio_mmc_enable_dma(host, false); if (ret >= 0) ret = -EIO; host->chan_rx = NULL; @@ -116,7 +117,6 @@ pio: } dev_warn(&host->pdev->dev, "DMA failed: %d, falling back to PIO\n", ret); - tmio_mmc_enable_dma(host, false); } dev_dbg(&host->pdev->dev, "%s(): desc %p, cookie %d, sg[%d]\n", __func__, @@ -185,6 +185,7 @@ static void tmio_mmc_start_dma_tx(struct pio: if (!desc) { /* DMA failed, fall back to PIO */ + tmio_mmc_enable_dma(host, false); if (ret >= 0) ret = -EIO; host->chan_tx = NULL; @@ -197,7 +198,6 @@ pio: } dev_warn(&host->pdev->dev, "DMA failed: %d, falling back to PIO\n", ret); - tmio_mmc_enable_dma(host, false); } dev_dbg(&host->pdev->dev, "%s(): desc %p, cookie %d\n", __func__, -- 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/