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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 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 70FFCC34021 for ; Mon, 17 Feb 2020 17:37:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 534FF20725 for ; Mon, 17 Feb 2020 17:37:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728814AbgBQRhw (ORCPT ); Mon, 17 Feb 2020 12:37:52 -0500 Received: from bhuna.collabora.co.uk ([46.235.227.227]:42954 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726818AbgBQRhv (ORCPT ); Mon, 17 Feb 2020 12:37:51 -0500 Received: from localhost (unknown [IPv6:2a01:e0a:2c:6930:5cf4:84a1:2763:fe0d]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: bbrezillon) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id 326982934B4; Mon, 17 Feb 2020 17:37:50 +0000 (GMT) Date: Mon, 17 Feb 2020 18:37:47 +0100 From: Boris Brezillon To: Vitor Soares Cc: Jose.Abreu@synopsys.com, Joao.Pinto@synopsys.com, arnd@arndb.de, wsa@the-dreams.de, gregkh@linuxfoundation.org, bbrezillon@kernel.org, linux-kernel@vger.kernel.org, broonie@kernel.org, linux-i3c@lists.infradead.org Subject: Re: [RFC v2 0/4] Introduce i3c device userspace interface Message-ID: <20200217183747.6a18d6c4@collabora.com> In-Reply-To: <20200217155141.08e87b3f@collabora.com> References: <20200217155141.08e87b3f@collabora.com> Organization: Collabora X-Mailer: Claws Mail 3.17.4 (GTK+ 2.24.32; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 17 Feb 2020 15:51:41 +0100 Boris Brezillon wrote: > Hello Vitor, > > Sorry for taking so long to reply, and thanks for working on that topic. > > On Wed, 29 Jan 2020 13:17:31 +0100 > Vitor Soares wrote: > > > For today there is no way to use i3c devices from user space and > > the introduction of such API will help developers during the i3c device > > or i3c host controllers development. > > > > The i3cdev module is highly based on i2c-dev and yet I tried to address > > the concerns raised in [1]. > > > > NOTES: > > - The i3cdev dynamically request an unused major number. > > > > - The i3c devices are dynamically exposed/removed from dev/ folder based > > on if they have a device driver bound to it. > > May I ask why you need to automatically bind devices to the i3cdev > driver when they don't have a driver matching the device id > loaded/compiled-in? If we get the i3c subsystem to generate proper > uevents we should be able to load the i3cdev module and bind the device > to this driver using a udev rule. Hm, looks like we already send a proper MODALIAS [1], so we can actually implement this auto-bind to i3cdev in udev (fall back on i3cdev load+bind if no matching module is found). [1]https://elixir.bootlin.com/linux/latest/source/drivers/i3c/master.c#L269