From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 71DCFC433DF for ; Mon, 6 Jul 2020 04:51:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4D30320739 for ; Mon, 6 Jul 2020 04:51:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594011080; bh=IBp8tyBnj3Y2L0swdhp+79ynA2bQ68n3mPtdQrODtRU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=BPUwspWJ+FUN5r5KOkj62J9SrJ2NS7o0a9aPxlF/PTrQDa+JLj3QE5bRhEY0Dv6Dn Aa7+GzPzJSIw5yRcFia2Q7OwWoSuwxDpahazMXGpp4SkB1K8K/4t2KLuf6NwmN4Afs oRSQFcRUBZ8KAHJRpb9iH7qfmvXvgzAG9AIBgREE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728723AbgGFEvU (ORCPT ); Mon, 6 Jul 2020 00:51:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:43926 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728362AbgGFEvU (ORCPT ); Mon, 6 Jul 2020 00:51:20 -0400 Received: from localhost (unknown [122.182.251.219]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9F77120739; Mon, 6 Jul 2020 04:51:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594011079; bh=IBp8tyBnj3Y2L0swdhp+79ynA2bQ68n3mPtdQrODtRU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=TJkEHH2San4T44pjglxmA92z9tSBwJE1pkqPTDKMFCMLmiFnBOzWKsph7HiVpWavG 2uMjxlfUybdG0xjkQYrxpPJ9ovygbpeHdavo/xKvmu4lp1yiQjMViejRwZ2bKsslLX 1lXu7s7lLXwuvwIfDD2rkshFn8mbCHmbEJgCiWFQ= Date: Mon, 6 Jul 2020 10:21:15 +0530 From: Vinod Koul To: Andy Shevchenko Cc: Viresh Kumar , dmaengine@vger.kernel.org, Tsuchiya Yuto Subject: Re: [PATCH v1] dmaengine: dw: Initialize channel before each transfer Message-ID: <20200706045115.GC633187@vkoul-mobl> References: <20200705115620.51929-1-andriy.shevchenko@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200705115620.51929-1-andriy.shevchenko@linux.intel.com> Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org On 05-07-20, 14:56, Andy Shevchenko wrote: > In some cases DMA can be used only with a consumer which does runtime power > management and on the platforms, that have DMA auto power gating logic > (see comments in the drivers/acpi/acpi_lpss.c), may result in DMA losing > its context. Simple mitigation of this issue is to initialize channel > each time the consumer initiates a transfer. Applied, thanks -- ~Vinod