Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761559AbXJOPs2 (ORCPT ); Mon, 15 Oct 2007 11:48:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754714AbXJOPsU (ORCPT ); Mon, 15 Oct 2007 11:48:20 -0400 Received: from nf-out-0910.google.com ([64.233.182.184]:11639 "EHLO nf-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753775AbXJOPsT (ORCPT ); Mon, 15 Oct 2007 11:48:19 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=TW/RU2nsKu1IM3ZRzWOpkTVnVKUOw8nQR8/Ytiwuie1UHgX7YGQeZ+mjTJHXMQCP74+ajXuzs93iC6lkR6ZbmtOdQ4ZL4xUStHeWxcVc0aadTW5XVruKZmEmuG03RnHSr6RpNYlb1wF/8Gt8hWKi9T+mi5f2y/XcC3uoXq3PIvQ= Message-ID: Date: Mon, 15 Oct 2007 11:48:17 -0400 From: "Dmitry Torokhov" To: bryan.wu@analog.com Subject: Re: [PATCH try #3] Input/Joystick Driver: add support AD7142 joystick driver Cc: "Andrey Panin" , "Roel Kluin" <12o3l@tiscali.nl>, "Ahmed S. Darwish" , linux-input@atrey.karlin.mff.cuni.cz, linux-joystick@atrey.karlin.mff.cuni.cz, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, "Jean Delvare" In-Reply-To: <1192459625.6215.17.camel@roc-laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <1192459625.6215.17.camel@roc-laptop> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2306 Lines: 80 Hi Bryan, On 10/15/07, Bryan Wu wrote: > + > +static int ad7142_thread(void *nothing) > +{ > + do { > + wait_for_completion(&ad7142_completion); > + ad7142_decode(); > + enable_irq(CONFIG_BFIN_JOYSTICK_IRQ_PFX); > + } while (!kthread_should_stop()); > + No, this is not going to work well: - you at least need to reinitialize the completion before enabling IRQ, otherwise you will spin in a very tight loop - if noone would touch the joystick ad7142_clsoe would() block infinitely because noone would signal the completion and ad7142_thread() would never stop. Completion is just not a good abstraction here... Please use work abstraction and possibly a separate workqueue. > + > + ad7142_task = kthread_run(ad7142_thread, NULL, "ad7142_task"); > + if (IS_ERR(ad7142_task)) { > + printk(KERN_ERR "serio: Failed to start kseriod\n"); kseriod? > + return PTR_ERR(ad7142_task); > + } > + return 0; > +} > + > +static void ad7142_close(struct input_dev *dev) > +{ Don't you need to write something over i2c to tell the device to shut down? As it is now I expect the device to continue raising its IRQ until kernel decides that it is unhandled and should be ignored. > + free_irq(CONFIG_BFIN_JOYSTICK_IRQ_PFX, ad7142_interrupt); Ok, so you freeing IRQ here, but it is allocated in ad7142_probe(). What happen if you try to open device after it was closed? > + kthread_stop(ad7142_task); > +} > + > +static int __init ad7142_init(void) > +{ > + return i2c_add_driver(&ad7142_driver); > +} > + > +static void __exit ad7142_exit(void) > +{ > + i2c_del_driver(&ad7142_driver); > + input_unregister_device(ad7142_dev); input_unregister_device() should be in ad7142_detach_client? I am not sure i2c - there seems to be 2 interface styles and you probably need to use the new one. I am CC-inj Jean on this. > +} > + > +module_init(ad7142_init); > +module_exit(ad7142_exit); > -- > 1.5.3.4 > -- Dmitry - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/