From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752759AbbBRQMd (ORCPT ); Wed, 18 Feb 2015 11:12:33 -0500 Received: from mail-la0-f50.google.com ([209.85.215.50]:46480 "EHLO mail-la0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751571AbbBRQMc (ORCPT ); Wed, 18 Feb 2015 11:12:32 -0500 From: Linus Walleij To: linux-kernel@vger.kernel.org, Greg Kroah-Hartman , Grant Likely Cc: Thomas Gleixner , Robert Jarzmik , "David S. Miller" , Linus Walleij Subject: [PATCH] drivers: platform: parse IRQ flags from resources Date: Wed, 18 Feb 2015 17:12:18 +0100 Message-Id: <1424275938-3337-1-git-send-email-linus.walleij@linaro.org> X-Mailer: git-send-email 1.9.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This fixes a regression from the net subsystem: After commit d52fdbb735c36a209f36a628d40ca9185b349ba7 "smc91x: retrieve IRQ and trigger flags in a modern way" a regression would appear on some legacy platforms such as the ARM PXA Zylonite that specify IRQ resources like this: static struct resource r = { .start = X, .end = X, .flags = IORESOURCE_IRQ | IORESOURCE_IRQ_HIGHEDGE, }; The previous code would retrieve the resource and parse the high edge setting in the SMC91x driver, a use pattern that means every driver specifying an IRQ flag from a static resource need to parse resource flags and apply them at runtime. As we switched the code to use IRQ descriptors to retrieve the the trigger type like this: irqd_get_trigger_type(irq_get_irq_data(...)); the code would work for new platforms using e.g. device tree as the backing irq descriptor would have its flags properly set, whereas this kind of oldstyle static resources at no point assign the trigger flags to the corresponding IRQ descriptor. To make the behaviour identical on modern device tree and legacy static platform data platforms, modify platform_get_irq() to assign the trigger flags to the irq descriptor when a client looks up an IRQ from static resources. Fixes: d52fdbb735c3 ("smc91x: retrieve IRQ and trigger flags in a modern way") Tested-by: Robert Jarzmik Signed-off-by: Linus Walleij --- Greg/Grant: I'm a bit uncertain here. It's kind of unintuitive that the platform_get_irq() function go around setting trigger flags on IRQ descriptors, but it is *also* unintuitive that the descriptor has all the right flags from a device tree but not from an identical static resource. And it is bloated to have resource parsing in each and every driver. The alternative is to revert the offending patch and live with some resource parsing all over the place. (Such a patch is posted.) --- drivers/base/platform.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/base/platform.c b/drivers/base/platform.c index 9421fed40905..e68ab79df28b 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -101,6 +101,15 @@ int platform_get_irq(struct platform_device *dev, unsigned int num) } r = platform_get_resource(dev, IORESOURCE_IRQ, num); + /* + * The resources may pass trigger flags to the irqs that need + * to be set up. It so happens that the trigger flags for + * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER* + * settings. + */ + if (r && r->flags & IORESOURCE_BITS) + irqd_set_trigger_type(irq_get_irq_data(r->start), + r->flags & IORESOURCE_BITS); return r ? r->start : -ENXIO; #endif -- 1.9.3