Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752267AbcDRP54 (ORCPT ); Mon, 18 Apr 2016 11:57:56 -0400 Received: from arroyo.ext.ti.com ([192.94.94.40]:41970 "EHLO arroyo.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751519AbcDRP5y (ORCPT ); Mon, 18 Apr 2016 11:57:54 -0400 Subject: Re: [PATCH] gpio: omap: fix irq triggering in smart-idle wakeup mode To: Tony Lindgren , santosh shilimkar References: <1460458351-24187-1-git-send-email-grygorii.strashko@ti.com> <5710B3B9.4090807@ti.com> <571106F3.9070805@oracle.com> <20160415185429.GU5995@atomide.com> CC: Linus Walleij , Alexandre Courbot , Santosh Shilimkar , Sekhar Nori , Linux-OMAP , "linux-gpio@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Roger Quadros From: Grygorii Strashko Message-ID: <571503F7.4040304@ti.com> Date: Mon, 18 Apr 2016 18:57:43 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <20160415185429.GU5995@atomide.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1977 Lines: 47 On 04/15/2016 09:54 PM, Tony Lindgren wrote: > * santosh shilimkar [160415 08:22]: >> On 4/15/2016 2:26 AM, Grygorii Strashko wrote: >>> >>> Santosh, Tony, do you want me to perform any additional actions regarding this patch? >>> >> This patch should be run across family of SOCs to make >> sure wakeup works on all of those if not done already > > Also, I'm not sure if we can just drop this code in question. > > After this patch, what function updates the GPIO wkup_en registers > depending on enable_irq_wake()/disable_irq_wake()? > The main purpose of this patch is to *not* modify GPIO wkup_en registers depending of enable_irq_wake()/disable_irq_wake() :), instead all non wake up IRQs should be masked during suspend. The GPIO wkup_en registers should be always in sync with GPIO irq_en when GPIO IP is in smart-idle wakeup mode. And this is done now from omap_gpio_unmask_irq/omap_gpio_mask_irq(). See also [1]. In general, it is more or less similar to GIC + wakeupgen: - during normal work (including cpuidle) GIC irq_en and Wakeupgen wkup_en should be in sync always - during suspend - only IRQs, marked as wake up sources, should be left unmasked. Also, I've found old thread [2] where Santosh proposed to use IRQCHIP_MASK_ON_SUSPEND. And it was not possible, at that time, but now IRQCHIP_MASK_ON_SUSPEND can be used :), because OMAP GPIO driver was switched to use generic irq handler instead of chained, so now OMAP GPIO irqs are properly handled by IRQ PM core. [chained irqs (and chained irq handles) are not disabled during suspend/resume and they are not maintained by IRQ PM core as result they can trigger way too early on resume when OMAP GPIO is not ready/powered.] I've tested it on: am57x-evm, am437x-idk-evm, omap4-panda [1] https://lkml.org/lkml/2016/4/12/676 [2] https://lkml.org/lkml/2012/8/26/1 https://groups.google.com/forum/#!msg/linux.kernel/iXJ5Y568B3Q/hZ39bSlcs0kJ -- regards, -grygorii