From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Subject: [v2,1/2] dma-mapping: move dma configuration to bus infrastructure From: Christoph Hellwig Message-Id: <20180322081705.GB29444@lst.de> Date: Thu, 22 Mar 2018 09:17:05 +0100 To: Bharat Bhushan Cc: Nipun Gupta , "robin.murphy@arm.com" , "hch@lst.de" , "linux@armlinux.org.uk" , "gregkh@linuxfoundation.org" , "m.szyprowski@samsung.com" , "bhelgaas@google.com" , "zajec5@gmail.com" , "andy.gross@linaro.org" , "david.brown@linaro.org" , "dan.j.williams@intel.com" , "vinod.koul@intel.com" , "thierry.reding@gmail.com" , "robh+dt@kernel.org" , "frowand.list@gmail.com" , "jarkko.sakkinen@linux.intel.com" , "rafael.j.wysocki@intel.com" , "dmitry.torokhov@gmail.com" , "johan@kernel.org" , "msuchanek@suse.de" , "linux-kernel@vger.kernel.org" , "iommu@lists.linux-foundation.org" , "linux-wireless@vger.kernel.org" , "linux-arm-msm@vger.kernel.org" , "linux-soc@vger.kernel.org" , "dmaengine@vger.kernel.org" , "dri-devel@lists.freedesktop.org" , "linux-tegra@vger.kernel.org" , "devicetree@vger.kernel.org" , "linux-pci@vger.kernel.org" , Leo Li List-ID: PiA+ICtpbnQgZG1hX2NvbmZpZ3VyZShzdHJ1Y3QgZGV2aWNlICpkZXYpCj4gPiArewo+ID4gKwlp ZiAoZGV2LT5idXMtPmRtYV9jb25maWd1cmUpCj4gPiArCQlyZXR1cm4gZGV2LT5idXMtPmRtYV9j b25maWd1cmUoZGV2KTsKPiAKPiBXaGF0IGlmIGRtYV9jb21tb25fY29uZmlndXJlKCkgaXMgY2Fs bGVkIGluIGNhc2UgImJ1cy0+ZG1hX2NvbmZpZ3VyZSIgaXMgbm90IGRlZmluZWQ/CgpUaGVuIHdl J2Qgc3RpbGwgaGF2ZSBhIGRlcGVuZGVuY3kgb2YgY29tbW9uIGNvZGUgb24gT0YgYW5kIEFDUEku CgpPbiB0aGUgb3RoZXIgaGFuZCB3ZSdkIGdldCBmcmVlIE9GIGFuZCBBQ1BJIGRtYSByYW5nZXMg cGFyc2luZyBmb3IKZXZlcnlvbmUsIHdoaWNoIG1pZ2h0IGJlIGhhbmR5LiAgQW5kIHdoaWNoIHdv dWxkIHJlYWxseSBoZWxwIG1pdGlnYXRpbmcKdGhlIHJpc2sgdGhhdCB3ZSBtaXNzZWQgc29tZSBi dXMgdGhhdCBnZXRzIGRtYSBjb25maWd1cmF0aW9uIGZyb20gT0YsCnNvIG1heWJlIGl0IGFjdHVh bGx5IGlzIGEgZ29vZCBpZGVhLiAgSSdkIGp1c3QgcmVuYW1lIGl0IHRvCmRtYV9kZWZhdWx0X2Nv bmZpZ3VyZSBvciBzaW1pbGFyIGluIHRoYXQgY2FzZS4KLS0tClRvIHVuc3Vic2NyaWJlIGZyb20g dGhpcyBsaXN0OiBzZW5kIHRoZSBsaW5lICJ1bnN1YnNjcmliZSBkbWFlbmdpbmUiIGluCnRoZSBi b2R5IG9mIGEgbWVzc2FnZSB0byBtYWpvcmRvbW9Admdlci5rZXJuZWwub3JnCk1vcmUgbWFqb3Jk b21vIGluZm8gYXQgIGh0dHA6Ly92Z2VyLmtlcm5lbC5vcmcvbWFqb3Jkb21vLWluZm8uaHRtbAo= From mboxrd@z Thu Jan 1 00:00:00 1970 From: "hch-jcswGhMUV9g@public.gmane.org" Subject: Re: [PATCH v2 1/2] dma-mapping: move dma configuration to bus infrastructure Date: Thu, 22 Mar 2018 09:17:05 +0100 Message-ID: <20180322081705.GB29444@lst.de> References: <1520868292-2479-1-git-send-email-nipun.gupta@nxp.com> <1521615323-4752-1-git-send-email-nipun.gupta@nxp.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Bharat Bhushan Cc: "zajec5-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org" , "linux-pci-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "jarkko.sakkinen-VuQAYsv1563Yd54FQh9/CA@public.gmane.org" , "david.brown-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org" , "thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org" , "frowand.list-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org" , "hch-jcswGhMUV9g@public.gmane.org" , "vinod.koul-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org" , "rafael.j.wysocki-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org" , "linux-I+IVW8TIWO2tmTQ+vhA3Yw@public.gmane.org" , "andy.gross-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org" , "msuchanek-l3A5Bk7waGM@public.gmane.org" , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-arm-msm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "johan-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org" , "robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org" , dri-devel-PD4FTy7X32k@public.gmane.org List-Id: linux-arm-msm@vger.kernel.org > > +int dma_configure(struct device *dev) > > +{ > > + if (dev->bus->dma_configure) > > + return dev->bus->dma_configure(dev); > > What if dma_common_configure() is called in case "bus->dma_configure" is not defined? Then we'd still have a dependency of common code on OF and ACPI. On the other hand we'd get free OF and ACPI dma ranges parsing for everyone, which might be handy. And which would really help mitigating the risk that we missed some bus that gets dma configuration from OF, so maybe it actually is a good idea. I'd just rename it to dma_default_configure or similar in that case. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from verein.lst.de ([213.95.11.211]:46090 "EHLO newverein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752504AbeCVIRH (ORCPT ); Thu, 22 Mar 2018 04:17:07 -0400 Date: Thu, 22 Mar 2018 09:17:05 +0100 From: "hch@lst.de" To: Bharat Bhushan Cc: Nipun Gupta , "robin.murphy@arm.com" , "hch@lst.de" , "linux@armlinux.org.uk" , "gregkh@linuxfoundation.org" , "m.szyprowski@samsung.com" , "bhelgaas@google.com" , "zajec5@gmail.com" , "andy.gross@linaro.org" , "david.brown@linaro.org" , "dan.j.williams@intel.com" , "vinod.koul@intel.com" , "thierry.reding@gmail.com" , "robh+dt@kernel.org" , "frowand.list@gmail.com" , "jarkko.sakkinen@linux.intel.com" , "rafael.j.wysocki@intel.com" , "dmitry.torokhov@gmail.com" , "johan@kernel.org" , "msuchanek@suse.de" , "linux-kernel@vger.kernel.org" , "iommu@lists.linux-foundation.org" , "linux-wireless@vger.kernel.org" , "linux-arm-msm@vger.kernel.org" , "linux-soc@vger.kernel.org" , "dmaengine@vger.kernel.org" , "dri-devel@lists.freedesktop.org" , "linux-tegra@vger.kernel.org" , "devicetree@vger.kernel.org" , "linux-pci@vger.kernel.org" , Leo Li Subject: Re: [PATCH v2 1/2] dma-mapping: move dma configuration to bus infrastructure Message-ID: <20180322081705.GB29444@lst.de> References: <1520868292-2479-1-git-send-email-nipun.gupta@nxp.com> <1521615323-4752-1-git-send-email-nipun.gupta@nxp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Sender: linux-pci-owner@vger.kernel.org List-ID: > > +int dma_configure(struct device *dev) > > +{ > > + if (dev->bus->dma_configure) > > + return dev->bus->dma_configure(dev); > > What if dma_common_configure() is called in case "bus->dma_configure" is not defined? Then we'd still have a dependency of common code on OF and ACPI. On the other hand we'd get free OF and ACPI dma ranges parsing for everyone, which might be handy. And which would really help mitigating the risk that we missed some bus that gets dma configuration from OF, so maybe it actually is a good idea. I'd just rename it to dma_default_configure or similar in that case.