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=-5.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 2159DC433E0 for ; Mon, 13 Jul 2020 20:55:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 02D472067D for ; Mon, 13 Jul 2020 20:55:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726542AbgGMUzR (ORCPT ); Mon, 13 Jul 2020 16:55:17 -0400 Received: from mga07.intel.com ([134.134.136.100]:49219 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726338AbgGMUzR (ORCPT ); Mon, 13 Jul 2020 16:55:17 -0400 IronPort-SDR: EbeLArq4HkKuXrlRxYpB/WS2qvAXL+eK3WEI4G9/favHK5tDRXMs139ILa9JUq6sYcrvGIBs++ dPhiTZl6KmIg== X-IronPort-AV: E=McAfee;i="6000,8403,9681"; a="213545772" X-IronPort-AV: E=Sophos;i="5.75,348,1589266800"; d="scan'208";a="213545772" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Jul 2020 13:55:16 -0700 IronPort-SDR: 7szJfcXPONfImWsDE0U1Og3oR6gRPzY9NXu27bBlEUhLsXyTzhLMHYMpnGwjaJkpOUSxedhjvm WmmYlkewsJUA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,348,1589266800"; d="scan'208";a="390288665" Received: from djiang5-mobl1.amr.corp.intel.com (HELO [10.212.172.11]) ([10.212.172.11]) by fmsmga001.fm.intel.com with ESMTP; 13 Jul 2020 13:55:15 -0700 Subject: Re: [PATCH v7 05/11] dmaengine: Introduce DMA-device device_caps callback To: Serge Semin , Andy Shevchenko Cc: Vinod Koul , Viresh Kumar , Dan Williams , Alexey Malahov , Thomas Bogendoerfer , Arnd Bergmann , Rob Herring , linux-mips@vger.kernel.org, devicetree@vger.kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org References: <20200709224550.15539-1-Sergey.Semin@baikalelectronics.ru> <20200709224550.15539-6-Sergey.Semin@baikalelectronics.ru> <20200710084503.GE3703480@smile.fi.intel.com> <20200710093834.su3nsjesnhntpd6d@mobilestation> From: Dave Jiang Message-ID: <07d4a977-1de6-b611-3d4f-7c7d6cd7fe5f@intel.com> Date: Mon, 13 Jul 2020 13:55:14 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200710093834.su3nsjesnhntpd6d@mobilestation> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org On 7/10/2020 2:38 AM, Serge Semin wrote: > On Fri, Jul 10, 2020 at 11:45:03AM +0300, Andy Shevchenko wrote: >> On Fri, Jul 10, 2020 at 01:45:44AM +0300, Serge Semin wrote: >>> There are DMA devices (like ours version of Synopsys DW DMAC) which have >>> DMA capabilities non-uniformly redistributed between the device channels. >>> In order to provide a way of exposing the channel-specific parameters to >>> the DMA engine consumers, we introduce a new DMA-device callback. In case >>> if provided it gets called from the dma_get_slave_caps() method and is >>> able to override the generic DMA-device capabilities. >> > >> In light of recent developments consider not to add 'slave' and a such words to the kernel. > > As long as the 'slave' word is used in the name of the dma_slave_caps > structure and in the rest of the DMA-engine subsystem, it will be ambiguous > to use some else terminology. If renaming needs to be done, then it should be > done synchronously for the whole subsystem. What about just calling it dma_device_caps? Consider this is a useful function not only slave DMA will utilize this. I can see this being useful for some of my future code with idxd driver. > > -Sergey > >> >> >> -- >> With Best Regards, >> Andy Shevchenko >> >>