From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756150Ab1EJL56 (ORCPT ); Tue, 10 May 2011 07:57:58 -0400 Received: from mail-bw0-f46.google.com ([209.85.214.46]:49155 "EHLO mail-bw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754319Ab1EJL55 (ORCPT ); Tue, 10 May 2011 07:57:57 -0400 Message-ID: <4DC927DF.1060808@ru.mvista.com> Date: Tue, 10 May 2011 15:56:15 +0400 From: Sergei Shtylyov User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-GB; rv:1.9.2.17) Gecko/20110414 Thunderbird/3.1.10 MIME-Version: 1.0 To: Nicolas Ferre CC: vinod.koul@intel.com, dan.j.williams@intel.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] dmaengine: at_hdmac: pause: no need to wait for FIFO empty References: <1304957497-22814-1-git-send-email-nicolas.ferre@atmel.com> In-Reply-To: <1304957497-22814-1-git-send-email-nicolas.ferre@atmel.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello. On 09-05-2011 20:11, Nicolas Ferre wrote: > The addition of the pause feature to atc_control an active wait was introduced > to check the FIFO empty event. Couldn't parse this -- did you forget "with"at the start of the statement? > This event was not always happening and > a timout contition was needed. > But, in some cases, this event depend on the peripheral connected to the > channel that is paused: FIFO becomes empty if the peripheral consumes data. > The timeout is pretty difficult to evaluate. Moreover, this check is not > needed. > In conclusion, it seems sensible to entirely remove the checking of > "FIFO empty" status when pausing. > Signed-off-by: Nicolas Ferre WBR, Sergei