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=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 1D67EC3A589 for ; Thu, 15 Aug 2019 14:05:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E720A20644 for ; Thu, 15 Aug 2019 14:05:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565877924; bh=lOyzTACCHACUENr3Alx4Ml7IiaPxhwyXrxfcBKWNBJc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=0V5Q2a7Ajho59jtz3nNl40XPNHgTukvbiBOdGXAcFxxJQFkbgMNPjwSQKmD6UQncZ 1Y+SIXVQEwZcl8MpxgklH4u5LsDQhaSjoskQ+De8mmSXv9yosx4tlkn7IiM9YFvtiX Amub051yphlZMCl+YI8iQJykyqZDURBUbl9rC2Y8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732684AbfHOOFT (ORCPT ); Thu, 15 Aug 2019 10:05:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:48612 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732211AbfHOOFT (ORCPT ); Thu, 15 Aug 2019 10:05:19 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 171BD20644; Thu, 15 Aug 2019 14:05:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565877918; bh=lOyzTACCHACUENr3Alx4Ml7IiaPxhwyXrxfcBKWNBJc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=PtMKB3MHNCBeXVQklF3aBuT4nPDLyDVWODXEgp48SJZXXqW5ovAbc9FVn+3tX8FKE pR1oRIblVReZKrtntkhiaZUu9/e7AjwFuaI4yblInt8eTNK1NW/ZB7XjP4YTtW5VlW eNlY1nowm+mCe1y3E25iAZAab2798Rbm62UuKYmw= Date: Thu, 15 Aug 2019 16:05:16 +0200 From: Greg Kroah-Hartman To: Christoph Hellwig Cc: Maxime Chevallier , Gavin Li , Laurentiu Tudor , Minas Harutyunyan , Alan Stern , Geoff Levand , Michal Simek , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , NXP Linux Team , Olav Kongas , Tony Prisk , Mathias Nyman , Bin Liu , linux-arm-kernel@lists.infradead.org, linux-usb@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, iommu@lists.linux-foundation.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 6/6] driver core: initialize a default DMA mask for platform device Message-ID: <20190815140516.GB7174@kroah.com> References: <20190811080520.21712-1-hch@lst.de> <20190811080520.21712-7-hch@lst.de> <20190815130325.GB17065@kroah.com> <20190815133812.GF12036@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190815133812.GF12036@lst.de> User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Thu, Aug 15, 2019 at 03:38:12PM +0200, Christoph Hellwig wrote: > On Thu, Aug 15, 2019 at 03:03:25PM +0200, Greg Kroah-Hartman wrote: > > > --- a/include/linux/platform_device.h > > > +++ b/include/linux/platform_device.h > > > @@ -24,6 +24,7 @@ struct platform_device { > > > int id; > > > bool id_auto; > > > struct device dev; > > > + u64 dma_mask; > > > > Why is the dma_mask in 'struct device' which is part of this structure, > > not sufficient here? Shouldn't the "platform" be setting that up > > correctly already in the "archdata" type callback? > > Becaus the dma_mask in struct device is a pointer that needs to point > to something, and this is the best space we can allocate for 'something'. > m68k and powerpc currently do something roughly equivalent at the moment, > while everyone else just has horrible, horrible hacks. As mentioned in > the changelog the intent of this patch is that we treat platform devices > like any other bus, where the bus allocates the space for the dma_mask. > The long term plan is to eventually kill that weird pointer indirection > that doesn't help anyone, but for that we need to sort out the basics > first. Ah, missed that, sorry. Ok, no objection from me. Might as well respin this series and I can queue it up after 5.3-rc5 is out (which will have your first 2 patches in it.) thanks, greg k-h