From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Dmitry Torokhov" Subject: Re: [PATCH try #3] Input/Joystick Driver: add support AD7142 joystick driver Date: Mon, 15 Oct 2007 11:48:17 -0400 Message-ID: References: <1192459625.6215.17.camel@roc-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1192459625.6215.17.camel@roc-laptop> Content-Disposition: inline Sender: owner-linux-input@atrey.karlin.mff.cuni.cz List-Help: List-Owner: List-Post: List-Unsubscribe: To: bryan.wu@analog.com 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 List-Id: linux-input@vger.kernel.org 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