Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751750AbdHAJdw (ORCPT ); Tue, 1 Aug 2017 05:33:52 -0400 Received: from mx07-00178001.pphosted.com ([62.209.51.94]:10286 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750832AbdHAJdt (ORCPT ); Tue, 1 Aug 2017 05:33:49 -0400 From: Pierre Yves MORDRET To: Vinod Koul , Peter Ujfalusi CC: Rob Herring , Mark Rutland , Maxime Coquelin , Alexandre TORGUE , Russell King , Dan Williams , "M'boumba Cedric Madianga" , Fabrice GASNIER , Herbert Xu , Fabien DESSENNE , Amelie DELAUNAY , "dmaengine@vger.kernel.org" , "devicetree@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v3 2/5] dmaengine: Add STM32 DMAMUX driver Thread-Topic: [PATCH v3 2/5] dmaengine: Add STM32 DMAMUX driver Thread-Index: AQHS9lJEsWaINqWfUEGtL1SBd5FJmqJfX72AgAObA4CAApdkgIAAI+EAgAgtzoCAAWBKAA== Date: Tue, 1 Aug 2017 09:32:50 +0000 Message-ID: References: <1499343623-5964-1-git-send-email-pierre-yves.mordret@st.com> <1499343623-5964-3-git-send-email-pierre-yves.mordret@st.com> <20170722065133.GT3053@localhost> <2b916330-9b65-f4d5-817f-79b66cc236b3@st.com> <20170726052930.GF3053@localhost> <20170731123157.GJ3053@localhost> In-Reply-To: <20170731123157.GJ3053@localhost> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: user-agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 x-ms-exchange-messagesentrepresentingtype: 1 x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.75.127.51] Content-Type: text/plain; charset="utf-8" Content-ID: MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-08-01_04:,, signatures=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by nfs id v719Xv0Q015330 Content-Length: 1179 Lines: 32 On 07/31/2017 02:31 PM, Vinod Koul wrote: > On Wed, Jul 26, 2017 at 07:38:02AM +0000, Pierre Yves MORDRET wrote: >>>>>> + >>>>>> +#ifndef __DMA_STM32_DMAMUX_H >>>>>> +#define __DMA_STM32_DMAMUX_H >>>>>> + >>>>>> +#if defined(CONFIG_STM32_DMAMUX) >>>>>> +int stm32_dmamux_set_config(struct device *dev, void *route_data, u32 chan_id); >>>>> >>>>> Why do we need a custom API in this case? >>>>> >>>> >>>> This API is called by DMA when a slave is requested by client. DMA can work >>>> without DMAMUX this API has been put in place to configure DMAMUX whether client >>>> is requesting a DMAMUX Channel instead of a DMA one. >>> >>> You mean the dmaengine driver right? >>> >> >> Yes. The API is mainly called by "device_config" through out STM32 DMA Driver >> when a router is in place for client. >> Please refer to Patch 4/5 on this set. > > Okay am thinking on why this can't be generic..? An optional router config > callback? > I would have liked to answer there is a callback within engine but unfortunately I didn't figure out one when I did my router's development. I've looked once more but again I can't find how to map chanID and request line without custom API.