From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from smtpfb2-g21.free.fr ([212.27.42.10]:55782 "EHLO smtpfb2-g21.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753699AbaBGL5T convert rfc822-to-8bit (ORCPT ); Fri, 7 Feb 2014 06:57:19 -0500 Received: from smtp5-g21.free.fr (smtp5-g21.free.fr [212.27.42.5]) by smtpfb2-g21.free.fr (Postfix) with ESMTP id E8286CA8880 for ; Fri, 7 Feb 2014 12:57:14 +0100 (CET) Date: Fri, 7 Feb 2014 12:57:21 +0100 From: Jean-Francois Moine To: Russell King - ARM Linux Cc: Daniel Vetter , devel@driverdev.osuosl.org, "alsa-devel@alsa-project.org" , David Airlie , Greg Kroah-Hartman , dri-devel , Hans Verkuil , Takashi Iwai , Sascha Hauer , Shawn Guo , "linux-arm-kernel@lists.infradead.org" , "linux-media@vger.kernel.org" Subject: Re: [PATCH RFC 26/46] drivers/base: provide an infrastructure for componentised subsystems Message-ID: <20140207125721.2d925387@armhf> In-Reply-To: <20140207094656.GY26684@n2100.arm.linux.org.uk> References: <20140102212528.GD7383@n2100.arm.linux.org.uk> <20140207094656.GY26684@n2100.arm.linux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-media-owner@vger.kernel.org List-ID: On Fri, 7 Feb 2014 09:46:56 +0000 Russell King - ARM Linux wrote: > On Fri, Feb 07, 2014 at 10:04:30AM +0100, Daniel Vetter wrote: > > I've chatted a bit with Hans Verkuil about this topic at fosdem and > > apparently both v4l and alsa have something like this already in their > > helper libraries. Adding more people as fyi in case they want to > > switch to the new driver core stuff from Russell. > > It's not ALSA, but ASoC which has this. Mark is already aware of this > and will be looking at it from an ASoC perspective. Russell, I started to use your code (which works fine, thanks), and it avoids a lot of problems, especially, about probe_defer in a DT context. I was wondering if your componentised mechanism could be extended to the devices defined by DT. In the DT, when a device_node is a phandle, this means it is referenced by some other device(s), and these device(s) will not start until the phandle device is registered. Then, the idea is to do a component_add() for such phandle devices in device_add() (device_register). Pratically, - the component_add() call in device_register would not include any bind/unbind callback function, so, this should be tested in component_bind/unbind(), - component_add would not be called if the device being added already called component_add in its probe function. A simple flag in the struct device_node should solve this problem. What do you think about this? -- Ken ar c'hentañ | ** Breizh ha Linux atav! ** Jef | http://moinejf.free.fr/