From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751315Ab1CPKsK (ORCPT ); Wed, 16 Mar 2011 06:48:10 -0400 Received: from na3sys009aog105.obsmtp.com ([74.125.149.75]:59124 "EHLO na3sys009aog105.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752543Ab1CPKsH convert rfc822-to-8bit (ORCPT ); Wed, 16 Mar 2011 06:48:07 -0400 Subject: Re: musb as module broken in 2.6.38 Mime-Version: 1.0 (Apple Message framework v1082) Content-Type: text/plain; charset=us-ascii From: Felipe Balbi In-Reply-To: <4D809455.9060901@ahsoftware.de> Date: Wed, 16 Mar 2011 12:48:03 +0200 Cc: Felipe Balbi , linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org Content-Transfer-Encoding: 8BIT Message-Id: <91490377-2892-46CA-827F-A80CD057490D@ti.com> References: <4D8018A9.6000800@ahsoftware.de> <20110316090327.GA2325@legolas.emea.dhcp.ti.com> <4D808729.9060608@ahsoftware.de> <20110316095541.GD2325@legolas.emea.dhcp.ti.com> <4D808E41.8040402@ahsoftware.de> <4D809150.4000600@ahsoftware.de> <4D809455.9060901@ahsoftware.de> To: Alexander Holler X-Mailer: Apple Mail (2.1082) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Mar 16, 2011, at 12:43 PM, Alexander Holler wrote: > Am 16.03.2011 11:38, schrieb Felipe Balbi: >> hi, >> >> On Mar 16, 2011, at 12:30 PM, Alexander Holler wrote: >>> Am 16.03.2011 11:24, schrieb Felipe Balbi: >>>> Hi, >>>> >>>> On Mar 16, 2011, at 12:17 PM, Alexander Holler wrote: >>>>>> static int __init omap2430_probe(struct platform_device *pdev) >>>>> >>>>> Neither omap2430_init() nor omap2430_probe() will be called here. >>>> >>>> and why is that ? It's even in sysfs already: >>>> >>>>>>> beagle linux # ls /sys/devices/platform/ | grep musb >>>>>>> musb-omap2430 >>> >>> Don't know, I haven't written or changed the driver. ;) >> >> hehe, Just thought that you had something in mind already. >> >> probe() functions are called when, in case of platform_devices, >> the name matches with driver name. musb-omap2430 platform_device >> is allocated in arch/arm/mach-omap2/usb-musb.c, then musb-2430 >> driver lives in drivers/usb/musb/omap2430.c. musb-2430 allocates a >> platform_device for musb-hdrc core driver. >> >> We did that because the same core is used in many different platforms >> (OMAP, discrete chips, ST-Ericsson, DaVinci, PCI cards, etc) so we >> needed to "abstract" platform-specific details such as clock handling >> and power management. >> >> There's still work to be done, for sure, e.g. the DMA part is still quite >> screwed up, but the drivers are correctly named which means they >> should be matching and probing. Now, musb-hdrc isn't probing, as >> you say, and I'd like to know why. I'll try to spend some time in >> it when I get back to the office. > > I currently assume it's something with > > subsys_initcall(omap2430_init); > > Have to read about subsys_initcall() and why omap2430_init isn't called here. I guess I know what the problem is. If you search for omap2430_init in vmlinux it won't be there. I guess when a directory is marked as obj-m, Kbuild won't search for symbols to be statically linked to vmlinux on that directory. Since we use the same Kconfig entry to select musb as module and include drivers/usb/musb directory into build system, we are falling into that case. Try changing drivers/usb/musb to obj-y in drivers/Makefile and see if things start working. -- balbi