Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932691AbbD0L4E (ORCPT ); Mon, 27 Apr 2015 07:56:04 -0400 Received: from arroyo.ext.ti.com ([192.94.94.40]:59938 "EHLO arroyo.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932282AbbD0L4B (ORCPT ); Mon, 27 Apr 2015 07:56:01 -0400 Message-ID: <553E23C9.3030603@ti.com> Date: Mon, 27 Apr 2015 14:55:53 +0300 From: Peter Ujfalusi User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: John Ogness , CC: , Sekhar Nori , Greg Kroah-Hartman , Sebastian Andrzej Siewior Subject: Re: [PATCH 2/3] dmaenegine: edma: allow pause/resume for non-cyclic mode References: <87vbghaiva.fsf@linutronix.de> In-Reply-To: <87vbghaiva.fsf@linutronix.de> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1542 Lines: 49 On 04/27/2015 02:52 PM, John Ogness wrote: > The 8250_omap serial driver relies on dmaengine_pause() actually > pausing the DMA transfer. Before this patch dmaengine_pause() is > a NOP for non-cylic DMA transfers. This allowed the 8250_omap > driver to read DMA buffers while the DMA was still active, > resulting in lost serial data. Acked-by: Peter Ujfalusi > Signed-off-by: John Ogness > --- > drivers/dma/edma.c | 7 +------ > 1 file changed, 1 insertion(+), 6 deletions(-) > > diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c > index bf09db7..88853af 100644 > --- a/drivers/dma/edma.c > +++ b/drivers/dma/edma.c > @@ -300,8 +300,7 @@ static int edma_dma_pause(struct dma_chan *chan) > { > struct edma_chan *echan = to_edma_chan(chan); > > - /* Pause/Resume only allowed with cyclic mode */ > - if (!echan->edesc || !echan->edesc->cyclic) > + if (!echan->edesc) > return -EINVAL; > > edma_pause(echan->ch_num); > @@ -312,10 +311,6 @@ static int edma_dma_resume(struct dma_chan *chan) > { > struct edma_chan *echan = to_edma_chan(chan); > > - /* Pause/Resume only allowed with cyclic mode */ > - if (!echan->edesc->cyclic) > - return -EINVAL; > - > edma_resume(echan->ch_num); > return 0; > } > -- P?ter -- 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/