Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751197AbdIOHoP (ORCPT ); Fri, 15 Sep 2017 03:44:15 -0400 Received: from mailout1.hostsharing.net ([83.223.95.204]:47583 "EHLO mailout1.hostsharing.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750787AbdIOHoN (ORCPT ); Fri, 15 Sep 2017 03:44:13 -0400 Date: Fri, 15 Sep 2017 09:44:39 +0200 From: Lukas Wunner To: Mika Westerberg Cc: Mario.Limonciello@dell.com, dvhart@infradead.org, linux-kernel@vger.kernel.org, platform-driver-x86@vger.kernel.org, hughsient@gmail.com, yehezkelshb@gmail.com Subject: Re: [PATCH v3] Add driver to force WMI Thunderbolt controller power status Message-ID: <20170915074439.GA17644@wunner.de> References: <1504884191-16528-1-git-send-email-mario.limonciello@dell.com> <20170913172024.GA8782@wunner.de> <27f4070678744d0f80761a95579b4cd3@ausx13mpc120.AMER.DELL.COM> <20170914091416.GA28049@wunner.de> <58820c0d563845659030881cd44cfe97@ausx13mpc120.AMER.DELL.COM> <20170914145919.GU2477@lahna.fi.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170914145919.GU2477@lahna.fi.intel.com> User-Agent: Mutt/1.6.1 (2016-04-27) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1083 Lines: 24 On Thu, Sep 14, 2017 at 05:59:19PM +0300, Mika Westerberg wrote: > On Thu, Sep 14, 2017 at 02:52:27PM +0000, Mario.Limonciello@dell.com wrote: > > > Looking at drivers/platform/x86/wmi.c:wmi_dev_uevent() it seems that > > > a modalias consisting of "wmi:" followed by the GUID is sent to udevd. > > > For udevd to then load the module, I suspect you need to add a > > > MODULE_DEVICE_TABLE(wmi, ...) to your driver. > > > > Ah, you're looking for this code from the WMI bus driver: > > https://github.com/torvalds/linux/blob/master/drivers/platform/x86/wmi.c#L724 > > > > That happens when the bus is initialized. > > That's right you get the uevent and whatnot but Lucas means that if you > don't have MODULE_DEVICE_TABLE(wmi, ...) in the driver, udev cannot load > the module automatically when the device appears. Digging a bit deeper I notice the wmi drivers seem to solve this by directly declaring a MODULE_ALIAS(), which is also present in Mario's driver. Mario, have you tested if auto-loading works if compiled as a module? If so, sorry for the noise. Thanks, Lukas