From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laurent Pinchart Subject: Re: [PATCH v6 10/25] iommu: exynos: remove useless device_add/remove callbacks Date: Mon, 18 May 2015 22:37:35 +0300 Message-ID: <3790451.FWdEsNZUcL@avalon> References: <1430727380-10912-1-git-send-email-m.szyprowski@samsung.com> <5559D66A.5070406@samsung.com> <20150518170430.GK20611@8bytes.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20150518170430.GK20611-zLv9SwRftAIdnm+yROfE0A@public.gmane.org> 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: Joerg Roedel Cc: Thierry Reding , linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Shaik Ameer Basha , Joonyoung Shim , Arnd Bergmann , Rob Herring , Inki Dae , Seung-Woo Kim , Will Deacon , Tomasz Figa , linaro-mm-sig-cunTk1MwBs8s++Sfvej+rw@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, Kukjin Kim , Kyungmin Park , Javier Martinez Canillas , Cho KyongHo , David Wodhouse , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: iommu@lists.linux-foundation.org Hi Joerg, On Monday 18 May 2015 19:04:30 Joerg Roedel wrote: > On Mon, May 18, 2015 at 02:09:14PM +0200, Marek Szyprowski wrote: > > > Hmm, will this remove support for iommu-groups in the exynos driver? I > > > am still working on the default-domain patch-set which makes iommu-group > > > support mandatory for iommu-drivers. > > > > I you wish, I can leave this code. iommu-groups were not used at all > > on Exynos, so I thought that there is no point keeping useless code. > > Yes, please keep the iommu-goups support, it will be required at some > point. I think the concept of iommu groups isn't very well understood, hence the little love it receives from developers who conclude it's useless. I can't blame anyone, I don't do any better. Could I convince you to include documentation in your next patch series that touches iommu groups ? Could you please have a look at my "[RFC/PATCH 0/9] IOMMU probe deferral support" patch series in the context of iommu groups ? The series pretty much drops groups support from the ipmmu-vmsa driver, not because of a real desire to do so, but because I wasn't sure how to keep them. Tips would be appreciated. -- Regards, Laurent Pinchart