From mboxrd@z Thu Jan 1 00:00:00 1970 From: Grygorii Strashko Subject: Re: [PATCH v3 1/3] gpio: davinci: add OF support Date: Mon, 14 Oct 2013 15:25:22 +0300 Message-ID: <525BE2B2.8020105@ti.com> References: <1380902596-4693-1-git-send-email-sujithkv@ti.com> <1380902596-4693-2-git-send-email-sujithkv@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: Errors-To: davinci-linux-open-source-bounces-VycZQUHpC/PFrsHnngEfi1aTQe2KTcn/@public.gmane.org To: Prabhakar Lad , Linus Walleij Cc: Mark Rutland , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , DLOS , Pawel Moll , LDOC , Stephen Warren , LKML , Rob Herring , "linux-gpio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Rob Landley , Ian Campbell , LAK List-Id: devicetree@vger.kernel.org Hi Prabhakar Lad, On 10/11/2013 07:18 PM, Prabhakar Lad wrote: > Hi Linus, > > On 10/11/13, Linus Walleij wrote: >> On Fri, Oct 11, 2013 at 4:59 PM, Prabhakar Lad >> wrote: >>> On 10/11/13, Linus Walleij wrote: >>>> On Fri, Oct 4, 2013 at 6:03 PM, Prabhakar Lad >>>> wrote: >> >>>>> +- ti,davinci-gpio-irq-base: Base from where GPIO interrupt numbering >>>>> starts. >>>> >>>> What is this? >>>> >>>> If I have ever ACKed this I have been drunk. I take it back. >>>> >>> here is the ACK https://patchwork.kernel.org/patch/2721181/ >> >> And as suspected that version of the patch did not contain >> this strange node property. >> > The property did exist in the patch 'intc_irq_num', I just renamed > it and gave a proper description to it. > >> Don't keep my ACK on patches if you change basic stuff like >> that, they need to be re-acked, this runs the risk of abusing >> my trust amongst other subsystem maintainers who might >> go and merge this because "aha the GPIO maintainer >> thinks that this is OK". >> > Agreed, I carry forwarded the ACK since it had minor changes. > >>>> This "base" is a Linux-specific thing and has no place in the >>>> device tree, and shall not be there. You have to find some way to >>>> avoid this, what do you think some other OS should do with >>>> this value... >>>> >>>> All IRQs in Linux are assumed to be dynamically assigned numbers >>>> nowadays, with a property like this you can never switch on >>>> SPARSE_IRQ for the DaVinci. >>>> >>> Can you point to any alternative solution if you have any ? >> >> First convert this GPIO driver to use an irqdomain to map >> HW IRQs to Linux IRQs, and grab a few IRQ descriptors >> dynamically off the irq descriptor heap. >> Example: commit >> a6c45b99a658521291cfb66ecf035cc58b38f206 >> "pinctrl/coh901: use irqdomain, allocate irqdescs" >> >> Then on a longer term convert DaVinci to use dynamically >> allocated IRQs for all interrupt controllers, and move it over >> to SPARSE_IRQ so you know this works. >> > Thanks for the pointers. > Could it be possible to use "interrupts" and "interrupt-names" to identify assigned banked & unbanked IRQs? For example DM646x (http://www.ti.com/lit/ug/sprueq8a/sprueq8a.pdf): interrupts = <48 IRQ_TYPE_EDGE_BOTH>, <49 IRQ_TYPE_EDGE_BOTH>, <50 IRQ_TYPE_EDGE_BOTH>, <51 IRQ_TYPE_EDGE_BOTH>, <52 IRQ_TYPE_EDGE_BOTH>, <53 IRQ_TYPE_EDGE_BOTH>, <54 IRQ_TYPE_EDGE_BOTH>, <55 IRQ_TYPE_EDGE_BOTH>, <56 IRQ_TYPE_EDGE_BOTH>, <57 IRQ_TYPE_EDGE_BOTH>, <58 IRQ_TYPE_EDGE_BOTH>; interrupt-names = "gpio0", "gpio1", "gpio2", "gpio3", "gpio4", "gpio5", "gpio6", "gpio7", "bank0", "bank1", "bank2"; For example OMAP-L138 (http://www.ti.com/lit/ug/spruh77a/spruh77a.pdf): interrupts = <42 IRQ_TYPE_EDGE_BOTH>, <43 IRQ_TYPE_EDGE_BOTH>, <44 IRQ_TYPE_EDGE_BOTH>, <45 IRQ_TYPE_EDGE_BOTH>, <46 IRQ_TYPE_EDGE_BOTH>, <47 IRQ_TYPE_EDGE_BOTH>, <48 IRQ_TYPE_EDGE_BOTH>, <49 IRQ_TYPE_EDGE_BOTH>, <50 IRQ_TYPE_EDGE_BOTH>; interrupt-names = "bank0", "bank1", "bank2", "bank3", "bank4", "bank5", "bank6", "bank7", "bank8"; For example Keystone 66AK2E05/02 (http://www.ti.com/lit/ds/sprs865a/sprs865a.pdf and http://www.ti.com/lit/ug/sprugv1/sprugv1.pdf): interrupts = , , [..] , ; interrupt-names = "gpio0", "gpio1", [...], "gpio30", "gpio31"; So then, following properties would not be needed at all, because all inf. can be taken from interrupt's properties: +- ti,davinci-gpio-irq-base: Base from where GPIO interrupt numbering starts. +- ti,davinci-gpio-unbanked: The number of GPIOs that have an individual interrupt line to processor. It should work good if Davinci-gpio driver will be converted to use linear IRQ domains for banked irqs. Regards, -grygorii