From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sascha Hauer Subject: Re: [PATCH v2 1/4] dt: bindings: mmc: Document the practice of using subnodes for slots Date: Mon, 2 Jun 2014 08:45:13 +0200 Message-ID: <20140602064513.GQ15686@pengutronix.de> References: <1401563014-13856-1-git-send-email-hdegoede@redhat.com> <1401563014-13856-2-git-send-email-hdegoede@redhat.com> <538AF124.9040106@redhat.com> Reply-To: linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Return-path: In-Reply-To: <538AF124.9040106-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> List-Post: , List-Help: , List-Archive: Sender: linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org List-Subscribe: , List-Unsubscribe: , Content-Disposition: inline To: Hans de Goede Cc: Olof Johansson , linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org, Chris Ball , Ulf Hansson , Maxime Ripard , Arend van Spriel , Chen-Yu Tsai , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" , "linux-mmc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , devicetree List-Id: devicetree@vger.kernel.org On Sun, Jun 01, 2014 at 11:23:48AM +0200, Hans de Goede wrote: > Hi, > > >Neither seems to actually ever have been used with > >more than one slot. I doubt anyone building an exynos-based system > >will ever do a multi-slot solution, and it seems that the at91 driver > >doesn't actually handle more than one slot. > > > >I'm personally not that excited about complicating the bindings by > >opening up for this -- I would rather work towards removing the > >concept of slots if it's one of those things that are going to remain > >unused. We have actually been talking about reworking the dw_mmc > >binding to remove the slot concept (and simplify the driver by doing > >so). > > I'm fine with removing the slot subnode, I added it because of it being > brought up in the powerup sequence discussion. I explicitly asked there > if adding such a subnode level was seen as desirable but nobody > answered :| MMC bus support was removed back in 2007: | commit b855885e3b60cf6f9452848712a62517b94583eb | Author: Pierre Ossman | Date: Wed Jan 3 19:47:29 2007 +0100 | | mmc: deprecate mmc bus topology | | The classic MMC bus was defined as multi card bus | system, which is reflected in the design in the MMC | layer. | | When SD showed up, the bus topology was abandoned | and a star topology (one card per host) was mandated. | MMC version 4 has followed this, officially deprecating | the bus topology. | | As we do not have any known users of the bus | topology we can remove support for it. This will | simplify the code and rectify some incorrect | assumptions in the newer additions. | | Signed-off-by: Pierre Ossman I doubt we will ever need support for it. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |