From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753898Ab2ITJrM (ORCPT ); Thu, 20 Sep 2012 05:47:12 -0400 Received: from mga09.intel.com ([134.134.136.24]:25790 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750962Ab2ITJrI convert rfc822-to-8bit (ORCPT ); Thu, 20 Sep 2012 05:47:08 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.80,453,1344236400"; d="scan'208";a="208557995" Message-ID: <1348134206.13371.40.camel@smile> Subject: Re: [PATCH 6/7] dw_dmac: check if controller supports LLP From: Andy Shevchenko To: viresh kumar Cc: Vinod Koul , spear-devel@list.st.com, linux-kernel@vger.kernel.org, Hein Tibosch Date: Thu, 20 Sep 2012 12:43:26 +0300 In-Reply-To: References: <1347867577-13170-1-git-send-email-andriy.shevchenko@linux.intel.com> <1347867577-13170-7-git-send-email-andriy.shevchenko@linux.intel.com> Organization: Intel Finland Oy Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT X-Mailer: Evolution 3.4.3-1 Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2012-09-18 at 12:43 +0530, viresh kumar wrote: > On Mon, Sep 17, 2012 at 1:09 PM, Andy Shevchenko > wrote: > > Some controllers have the reduced functionality where the LLP multi block > > transfers are not supported. This patch introduces a check and refuses to deal > > with such devices. > > > > Signed-off-by: Andy Shevchenko > > --- > > drivers/dma/dw_dmac.c | 35 ++++++++++++++++++++++++++++++++++- > > drivers/dma/dw_dmac_regs.h | 4 ++++ > > 2 files changed, 38 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c > > index fdb7d5a..00958ad 100644 > > --- a/drivers/dma/dw_dmac.c > > +++ b/drivers/dma/dw_dmac.c > > @@ -647,6 +647,12 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, > > unsigned int dst_width; > > u32 ctllo; > > > > + if (dwc->nollp) { > > + dev_dbg(chan2dev(&dwc->chan), > > + "channel doesn't support LLP transfers\n"); > > + return NULL; > > + } > > But this could have been a single block request. Isn't it? I think we could discard this comment in regard to comments on next patch. -- Andy Shevchenko Intel Finland Oy