From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-vk0-f66.google.com ([209.85.213.66]:33529 "EHLO mail-vk0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932236AbeFKOKa (ORCPT ); Mon, 11 Jun 2018 10:10:30 -0400 Received: by mail-vk0-f66.google.com with SMTP id 200-v6so12371949vkc.0 for ; Mon, 11 Jun 2018 07:10:30 -0700 (PDT) MIME-Version: 1.0 References: <20180604175911.799-1-marek.vasut+renesas@gmail.com> <967b800e-c935-aa35-da5a-ca3672fd18c2@gmail.com> <47e87deb-a7a8-4780-53b5-4e4ed6e1bac3@gmail.com> In-Reply-To: <47e87deb-a7a8-4780-53b5-4e4ed6e1bac3@gmail.com> From: Geert Uytterhoeven Date: Mon, 11 Jun 2018 16:10:17 +0200 Message-ID: Subject: Re: [PATCH V3] ARM: shmobile: Rework the PMIC IRQ line quirk To: Marek Vasut Cc: Linux ARM , Geert Uytterhoeven , Kuninori Morimoto , Linux-Renesas , Wolfram Sang , Simon Horman , Marek Vasut Content-Type: text/plain; charset="UTF-8" Sender: linux-renesas-soc-owner@vger.kernel.org List-ID: Hi Marek, On Mon, Jun 11, 2018 at 4:04 PM Marek Vasut wrote: > On 06/11/2018 03:49 PM, Geert Uytterhoeven wrote: > > On Mon, Jun 11, 2018 at 3:39 PM Marek Vasut wrote: > >> On 06/11/2018 03:03 PM, Geert Uytterhoeven wrote: > >>> On Mon, Jun 11, 2018 at 2:15 PM Marek Vasut wrote: > >>>> On 06/11/2018 11:56 AM, Geert Uytterhoeven wrote: > >>>>> On Mon, Jun 4, 2018 at 7:59 PM Marek Vasut wrote: > >>>>>> Rather than hard-coding the quirk topology, which stopped scaling, > >>>>>> parse the information from DT. The code looks for all compatible > >>>>>> PMICs -- da9036 and da9210 -- and checks if their IRQ line is tied > >>>>>> to the same pin. If so, the code sends a matching sequence to the > >>>>>> PMIC to deassert the IRQ. > > > >>>>>> + ret = of_property_read_u32(np, "reg", &addr); > >>>>>> + if (ret) > >>>>>> + return ret; > >>>>> > >>>>> I think it's safer to skip this entry and continue, after calling > >>>>> kfree(quirk), of course. > >>>>> > >>>>>> + > >>>>>> + quirk->id = id; > >>>>>> + quirk->i2c_msg.addr = addr; > >>>>>> + quirk->shared = false; > >>>>>> + > >>>>>> + ret = of_irq_parse_one(np, 0, &quirk->irq_args); > >>>>>> + if (ret) > >>>>>> + return ret; > >>>>> > >>>>> kfree(quirk) and continue... > >>>> > >>>> I wonder if it shouldn't rather free the entire list and abort ? > >>> > >>> "Be strict when sending, be liberal when receiving." > >> > >> Meaning ? I think "the language barrier is protecting me" (TM) > > > > Do the best you can, given the buggy DT you received. > > I.e. don't fail completely, just ignore the bad device node, and continue. > > But if you ignore node, you might as well ignore one which is shared and > then the system crashes due to IRQ storm anyway. So hum, what can we do ? Correct. If it's a critical node, it will crash regardless. If it's a non-critical node, you have the choice between aborting and crashing, or ignoring and keeping the system alive. Your call. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds From mboxrd@z Thu Jan 1 00:00:00 1970 From: geert@linux-m68k.org (Geert Uytterhoeven) Date: Mon, 11 Jun 2018 16:10:17 +0200 Subject: [PATCH V3] ARM: shmobile: Rework the PMIC IRQ line quirk In-Reply-To: <47e87deb-a7a8-4780-53b5-4e4ed6e1bac3@gmail.com> References: <20180604175911.799-1-marek.vasut+renesas@gmail.com> <967b800e-c935-aa35-da5a-ca3672fd18c2@gmail.com> <47e87deb-a7a8-4780-53b5-4e4ed6e1bac3@gmail.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Marek, On Mon, Jun 11, 2018 at 4:04 PM Marek Vasut wrote: > On 06/11/2018 03:49 PM, Geert Uytterhoeven wrote: > > On Mon, Jun 11, 2018 at 3:39 PM Marek Vasut wrote: > >> On 06/11/2018 03:03 PM, Geert Uytterhoeven wrote: > >>> On Mon, Jun 11, 2018 at 2:15 PM Marek Vasut wrote: > >>>> On 06/11/2018 11:56 AM, Geert Uytterhoeven wrote: > >>>>> On Mon, Jun 4, 2018 at 7:59 PM Marek Vasut wrote: > >>>>>> Rather than hard-coding the quirk topology, which stopped scaling, > >>>>>> parse the information from DT. The code looks for all compatible > >>>>>> PMICs -- da9036 and da9210 -- and checks if their IRQ line is tied > >>>>>> to the same pin. If so, the code sends a matching sequence to the > >>>>>> PMIC to deassert the IRQ. > > > >>>>>> + ret = of_property_read_u32(np, "reg", &addr); > >>>>>> + if (ret) > >>>>>> + return ret; > >>>>> > >>>>> I think it's safer to skip this entry and continue, after calling > >>>>> kfree(quirk), of course. > >>>>> > >>>>>> + > >>>>>> + quirk->id = id; > >>>>>> + quirk->i2c_msg.addr = addr; > >>>>>> + quirk->shared = false; > >>>>>> + > >>>>>> + ret = of_irq_parse_one(np, 0, &quirk->irq_args); > >>>>>> + if (ret) > >>>>>> + return ret; > >>>>> > >>>>> kfree(quirk) and continue... > >>>> > >>>> I wonder if it shouldn't rather free the entire list and abort ? > >>> > >>> "Be strict when sending, be liberal when receiving." > >> > >> Meaning ? I think "the language barrier is protecting me" (TM) > > > > Do the best you can, given the buggy DT you received. > > I.e. don't fail completely, just ignore the bad device node, and continue. > > But if you ignore node, you might as well ignore one which is shared and > then the system crashes due to IRQ storm anyway. So hum, what can we do ? Correct. If it's a critical node, it will crash regardless. If it's a non-critical node, you have the choice between aborting and crashing, or ignoring and keeping the system alive. Your call. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds