From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755976AbdIHPKc (ORCPT ); Fri, 8 Sep 2017 11:10:32 -0400 Received: from conssluserg-06.nifty.com ([210.131.2.91]:62425 "EHLO conssluserg-06.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753072AbdIHPKa (ORCPT ); Fri, 8 Sep 2017 11:10:30 -0400 DKIM-Filter: OpenDKIM Filter v2.10.3 conssluserg-06.nifty.com v88FAGmp017699 X-Nifty-SrcIP: [209.85.161.170] X-Google-Smtp-Source: ADKCNb6bSyv1Gg9cFfd64tRoi3u+MviQSwz4TaNLTbCiOF0kkQA4fP82oEdZzcBA1KhEISZvOmu40LhY+0qrKGmW6Tk= MIME-Version: 1.0 In-Reply-To: References: <1504784522-26841-1-git-send-email-yamada.masahiro@socionext.com> <1504784522-26841-3-git-send-email-yamada.masahiro@socionext.com> From: Masahiro Yamada Date: Sat, 9 Sep 2017 00:09:35 +0900 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v4 2/6] irqdomain: clear trigger type in irq_domain_push_irq() To: Marc Zyngier Cc: Thomas Gleixner , Linus Walleij , linux-gpio@vger.kernel.org, Rob Herring , Jassi Brar , devicetree@vger.kernel.org, Jason Cooper , Masami Hiramatsu , David Daney , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Marc, 2017-09-07 21:25 GMT+09:00 Marc Zyngier : > On 07/09/17 12:41, Masahiro Yamada wrote: >> Prior to the addition of irq_domain_push_irq(), the hierarchy >> IRQ domain always allocates IRQs from the outer-most domain. >> Each irqchip usually calls irq_domain_alloc_irqs_parent(), >> ascending the topology up to the root irqchip. >> >> The brand-new function irq_domain_push_irq() allows us to allocate >> IRQs for parent domain first, then add a child irq_data to the >> tail of the chain. >> >> For the new use-case, if the parent sets a temporary trigger type, >> it may differ from the type requested to the outer-most irqchip, >> then irq_create_fwspec_mapping() warns "type mismatch, failed to map..." >> >> Clear the trigger type when a new irq_data is connected to the chain. >> >> Signed-off-by: Masahiro Yamada >> --- >> >> Changes in v4: >> - Newly added >> >> >> kernel/irq/irqdomain.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c >> index da3e0b6..18d11b9 100644 >> --- a/kernel/irq/irqdomain.c >> +++ b/kernel/irq/irqdomain.c >> @@ -1532,6 +1532,9 @@ int irq_domain_push_irq(struct irq_domain *domain, int virq, void *arg) >> tail_irq_data->chip = NULL; >> tail_irq_data->chip_data = NULL; >> >> + /* clear the trigger type to avoid "type mismatch" error */ >> + irqd_set_trigger_type(tail_irq_data, IRQ_TYPE_NONE); >> + > > This feels wrong. The initial interrupt hierarchy does have a set > trigger, because it has been configured already, and switching it to > NONE is hiding the fact that you're setting it to another, conflicting > value. > > Your new fwspec should have a type that is really compatible with with > the underlying interrupt, however "temporary". If it is not, you have a > problem. > My motivation is to describe interrupt connection by DT property, like follows: interrupts = <48 4>, <49 4>, <50 4>, <51 4>, <52 4>, <53 4>, <54 4>, <55 4>, <56 4>, <57 4>, <58 4>, <59 4>, <60 4>, <61 4>, <62 4>, <63 4>, <154 4>, <155 4>, <156 4>, <157 4>, <158 4>; The number of cells is fixed, so I need to give something as the second parameter. The "4" may not be a real trigger type, it is just a temporal value to fill the space. The device may pass a different trigger type when it calls gpio_to_irq() && request_irq(). I cannot know the real trigger type until the device is probed. Having said that, if this is a bad idea, I will consider a different approach for my GPIO driver. -- Best Regards Masahiro Yamada