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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 65D31C433DF for ; Tue, 20 Oct 2020 07:17:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 19E7B2223C for ; Tue, 20 Oct 2020 07:17:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727320AbgJTHRM (ORCPT ); Tue, 20 Oct 2020 03:17:12 -0400 Received: from mga09.intel.com ([134.134.136.24]:53719 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726124AbgJTHRM (ORCPT ); Tue, 20 Oct 2020 03:17:12 -0400 IronPort-SDR: i3wJyDXz9VP42skEepGlEdBq/jOfBt5Vc7rvR7MpiPSCU6P53OYVW+opUjWVoG1/20AxGFWxit r7sdnXTNLJ5A== X-IronPort-AV: E=McAfee;i="6000,8403,9779"; a="167287121" X-IronPort-AV: E=Sophos;i="5.77,396,1596524400"; d="scan'208";a="167287121" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Oct 2020 00:17:11 -0700 IronPort-SDR: DBnv6vGrhQydhBtdhMIpzgRRmcF0NXZvtyxrNAgYhks1DLKHZYzr3g1hG3iBtMbOpCjLxFgpW5 kjMr4rD/1FTw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.77,396,1596524400"; d="scan'208";a="320550642" Received: from yilunxu-optiplex-7050.sh.intel.com (HELO localhost) ([10.239.159.141]) by orsmga006.jf.intel.com with ESMTP; 20 Oct 2020 00:17:07 -0700 Date: Tue, 20 Oct 2020 15:11:58 +0800 From: Xu Yilun To: Tom Rix Cc: mdf@kernel.org, linux-fpga@vger.kernel.org, linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org, lgoncalv@redhat.com, hao.wu@intel.com Subject: Re: [PATCH 1/2] fpga: dfl: add driver_override support Message-ID: <20201020071158.GC28746@yilunxu-OptiPlex-7050> References: <1602828151-24784-1-git-send-email-yilun.xu@intel.com> <1602828151-24784-2-git-send-email-yilun.xu@intel.com> <63d7730b-d9b8-c75d-16f6-3ebb507aabaa@redhat.com> <20201019040612.GA16172@yilunxu-OptiPlex-7050> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) Precedence: bulk List-ID: X-Mailing-List: linux-fpga@vger.kernel.org > >>> int __dfl_driver_register(struct dfl_driver *dfl_drv, struct module *owner) > >>> { > >>> - if (!dfl_drv || !dfl_drv->probe || !dfl_drv->id_table) > >>> + if (!dfl_drv || !dfl_drv->probe) > >> id_table is still needed for the normal case. > >> > >> Instead of removing this check, could you add something like > >> > >> || (!dfl_drv->is_override && !dfl_drv->id_table) > > I don't think it is needed. Seems is_override and !id_table are duplicated > > conditions for this implementation. And it may make confusing, e.g. could > > a driver been force matched when is_override is not set? > > > > I think we could make it simple, if the dfl driver didn't provide the > > id_table, normally it could not match any device. I think it could be > > easily understood by dfl driver developers. > > > Then an ASSERT should be added in dfl_bus_match() for id_entry. I didn't get your idea. What Assertion should be added for id_entry? BUG_ON(id_entry == NULL)? Then dfl-uio-pdev can't be inserted before driver_override is set. I think it is normal case that a driver is successfully registered but doesn't match any device because it provides no id_table. Thanks, Yilun.