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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7138CC433F5 for ; Thu, 19 May 2022 17:51:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241589AbiESRvo (ORCPT ); Thu, 19 May 2022 13:51:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51594 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241663AbiESRu3 (ORCPT ); Thu, 19 May 2022 13:50:29 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B653EB36CE; Thu, 19 May 2022 10:49:44 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 3E076B825C3; Thu, 19 May 2022 17:49:43 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 42F71C385AA; Thu, 19 May 2022 17:49:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1652982581; bh=9A5+aIyuXlTlURbYrnNECxCHAE/FESaqMNCsL6/awOI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Puppa7FBRvhE6BDdhEDwhEJWvRlwJNek6upoz4Dr5kf0mDHj/ln2DX4S+ztY5+U2P li2U6dtnwbQWT2DzDSeUBXj1B+Ks0lur/ohsr7Zo6HPaXQl1bPK4My2L2oQURzkH61 Wygy+6X6rvUAirXy1GXvHbF6nQKFmuDyjZIqN5p4kAYuBpNF9SkqWcBXXOR+AHZJqe 9RM2MvzrVBwE8BZCzeLHjzSV52j2siBqjmr32q2E498BIDkVs1KlBtBF+ouXpEx1hY yxH1Pgb/rzdcgk2/PBiGgx/H1S/B8cVx6ZTWf79pG6NThDKRs8Tt1oWc97caOZqmcl eLd11ncCWxqFw== Date: Thu, 19 May 2022 23:19:37 +0530 From: Vinod Koul To: Amelie Delaunay Cc: Maxime Coquelin , Alexandre Torgue , dmaengine@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] dmaengine: stm32-dmamux: avoid reset of dmamux if used by coprocessor Message-ID: References: <20220504161724.123180-1-amelie.delaunay@foss.st.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220504161724.123180-1-amelie.delaunay@foss.st.com> Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org On 04-05-22, 18:17, Amelie Delaunay wrote: > One of the two DMA controllers managed by the DMAMUX can be used by the > coprocessor. It is defined in the device tree with dma-masters. > When the two DMA controllers are used by the main CPU, > dma-masters = <&dma1, &dma2>; is specified in the device tree. > When one of the controllers is used by coprocessor (so not managed by > Linux), dma-masters = <&dma1>; is specified in the device tree. > In this case, Linux driver must not reset the DMAMUX, because it could have > been configured by the coprocessor to use the second DMA controller. > count is the number of DMA controllers defined in dma-masters property. > Reset only if resets property is found and valid in device tree, and if > the two DMA controllers are under Linux control. Applied, thanks -- ~Vinod