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=-6.7 required=3.0 tests=BAYES_00,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 D509CC4338F for ; Wed, 28 Jul 2021 06:20:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BB77060F9B for ; Wed, 28 Jul 2021 06:20:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231484AbhG1GUK (ORCPT ); Wed, 28 Jul 2021 02:20:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:57742 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231199AbhG1GUJ (ORCPT ); Wed, 28 Jul 2021 02:20:09 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id CF54560E78; Wed, 28 Jul 2021 06:20:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1627453208; bh=HkZZZEezLxlMdxDZomgJxlhl427+uiRZ9Ct6TVv0C30=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=h/1KrKm+01QsCnfkbvX81hBkzDtmqUwKPwlk1ryz8vToBIwzDojdLrnAI3gPhNJ9F pvPCn5ObN7yLurBD9+LTnPDNIamhU6eGh5ga+oprEpgUPT04Gie0cplbtjcPOg5LLF sprT6D8+hbPlazIutcQd2aYcMYSw4QBjAyZcOSSEr46RwNW4ZZ/elQ6XIafeLtaVML lRGVBOddJORcT0gPzF/vEeQFIhXsxs3iOQoVnpopnsXdsXYGEK4H13neLy6IAifT1J fOfYSm1FM73dQSn7+Owpe+Mdd7GWubAJkGqv71cwrw7Oba1xRU7O12hKK+8skKNlMZ xRf9YIfglFeaw== Date: Wed, 28 Jul 2021 11:50:04 +0530 From: Vinod Koul To: Biju Das Cc: Prabhakar Mahadev Lad , Chris Paterson , Geert Uytterhoeven , "dmaengine@vger.kernel.org" , Chris Brandt , "linux-renesas-soc@vger.kernel.org" Subject: Re: [PATCH v4 2/4] drivers: dma: sh: Add DMAC driver for RZ/G2L SoC Message-ID: References: <20210719092535.4474-1-biju.das.jz@bp.renesas.com> <20210719092535.4474-3-biju.das.jz@bp.renesas.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org Hi Biju, On 27-07-21, 13:45, Biju Das wrote: > > > + > > > + if (config->peripheral_config) { > > > + ch_cfg = config->peripheral_config; > > > + channel->chcfg = *ch_cfg; > > > + } > > > > can you explain what this the ch_cfg here and what does it represent? > > It is a 32 bit value represent channel config value which supplied by each client driver during slave config. > It contains information like transfer mode,src/destination data size, Ack mode, Level type, DMA request on rising edge or falling > Edge, request direction etc... > > For eg:- The channel config for SSI tx is (0x11228). > An example usage can be found here [1] > > [1] https://patchwork.kernel.org/project/linux-renesas-soc/patch/20210719134040.7964-8-biju.das.jz@bp.renesas.com/ Sorry I dont like passing numbers like this :( Can you explain what is meant by each of the above values and looks like some (if not all) can be derived (slave config as well as transaction properties) -- ~Vinod