Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753226Ab0AZKM2 (ORCPT ); Tue, 26 Jan 2010 05:12:28 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752460Ab0AZKM0 (ORCPT ); Tue, 26 Jan 2010 05:12:26 -0500 Received: from ns.penguin.cz ([84.21.108.25]:52233 "EHLO ns.penguin.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752207Ab0AZKMZ (ORCPT ); Tue, 26 Jan 2010 05:12:25 -0500 Subject: Re: gpio_keys and how PXA27x sets gpio_set_wake() (was Re: sharp c-3000 aka spitz: fix warn_on introduced in 2.6.32-rc1) From: Stanislav Brabec To: Eric Miao Cc: Andrew Morton , thommycheck@gmail.com, dbaryshkov@gmail.com, dtor@mail.ru, arminlitzel@web.de, linux-input@vger.kernel.org, kernel list , Dirk@opfer-online.de, "Rafael J. Wysocki" , lenz@cs.wisc.edu, rpurdie@rpsys.net, linux-arm-kernel , Pavel Machek , Cyril Hrubis , zaurus-devel@www.linuxtogo.org, omegamoon@gmail.com, Vojtech Pavlik In-Reply-To: References: <20100106071026.GD1382@ucw.cz> <20100107065230.GA1303@ucw.cz> <1264275669.9100.11.camel@utx.utx.cz> <1264286611.11766.49.camel@utx.utx.cz> Content-Type: text/plain; charset="ISO-8859-2" Date: Tue, 26 Jan 2010 11:13:44 +0100 Message-Id: <1264500824.4480.79.camel@utx.utx.cz> Mime-Version: 1.0 X-Mailer: Evolution 2.28.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2914 Lines: 61 Eric Miao wrota: > I prefer 2) - the ugly and hardcoded setup in spitz_pm.c should really > be removed. That's why the gpio_set_wake() and keypad_set_wake() > are introduced. I am unsure, whether gpio_keys driver is interested in the way, how wake happens. I guess that is interested only in the fact, that wake happened. Handling platform specific edge/level wake setup would only complicate the code. (In fact, even the PXA270 platform code does not exist yet - arch/arm/mach-pxa/mfp-pxa2xx.c:__mfp_config_gpio() is not capable to configure Power Manager Keyboard Wake-Up Enable Register (PKWR).) I talked to Vojt?ch Pavl?k and he told that 1 is correct: Follow include/linux/interrupt.h. Setting edge/level wake mode should be done in the platform file. The driver could use just irq_set_wake() and don't care about details. And irq_set_wake() should do something useful even for PKWR capable GPIO. > keypad_set_wake() is really specifically introduced for use by pxa27x_keypad > and no generic GPIO stuffs. So it's really annoying a GPIO will use > the PKWR as a wakeup GPIO, I'd recommend one still get this hard coded > into the platform file, with combination of WAKEUP_ON_LEVEL_HIGH (which > is specifically designed for keypad GPIOs) and keypad_set_wake(). Well, keypad_set_wake() seems to be possibly broken for GPIO 38. Imagine a device, that has a small keypad, but GPIO 38 has a different purpose that requires an edge triggered wakeup (PWER). I think that keypad_set_wake() reprograms it to PKWR. The problem affects gpio_keys: It is a driver implementing "one key per gpio". It now handles On/Off and lid switches on Zaurus. Lid switches are on "normal" GPIOs, On/Off switch is wired to PKWR capable GPIO. > The spitz, however, is doing a good job on this though it's using a GPIO > emulated matrix keypad, that there is a separate SPITZ_GPIO_KEY_INT, > which triggers whenever there is any key press on this matrix (I don't > know how that's designed in HW, but it seems to do that job), and > which can be setup as a GPIO wakeup. SPITZ_GPIO_KEY_INT happens if AC adapter is connected or key is pressed. Surprisingly, the key press logic is part of NAND flash controller CPLD. SPITZ_GPIO_KEY_INT==0 - it makes possible to wake Zaurus even from deep sleep by any key press. It would be impossible only with PKWR. I guess that this and implementation of keypad_set_wake() is a reason, why most devices suspend and resume correctly even if the irq_set_wake() refuses to configure wake and the warning is only visible symptom. ________________________________________________________________________ Stanislav Brabec http://www.penguin.cz/~utx -- 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/