From: Hanks Chen <hanks.chen@mediatek.com> To: Linus Walleij <linus.walleij@linaro.org> Cc: Rob Herring <robh@kernel.org>, CC Hwang <cc.hwang@mediatek.com>, <wsd_upstream@mediatek.com>, "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" <devicetree@vger.kernel.org>, Stephen Boyd <sboyd@kernel.org>, Sean Wang <sean.wang@kernel.org>, Loda Chou <loda.chou@mediatek.com>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, Marc Zyngier <marc.zyngier@arm.com>, "Mars Cheng" <mars.cheng@mediatek.com>, mtk01761 <wendell.lin@mediatek.com>, Matthias Brugger <matthias.bgg@gmail.com>, "moderated list:ARM/Mediatek SoC support" <linux-mediatek@lists.infradead.org>, linux-clk <linux-clk@vger.kernel.org> Subject: Re: [PATCH v2 05/11] pinctrl: mediatek: avoid virtual gpio trying to set reg Date: Wed, 8 Jan 2020 19:27:30 +0800 Message-ID: <1578482850.7554.18.camel@mtkswgap22> (raw) In-Reply-To: <CACRpkdZUxpQ1tS9mKG9tc_U==M2BL9HwXt3DS1t413GGSEaVTA@mail.gmail.com> On Tue, 2020-01-07 at 11:20 +0100, Linus Walleij wrote: > On Mon, Dec 23, 2019 at 4:11 AM Hanks Chen <hanks.chen@mediatek.com> wrote: > > On Fri, 2019-08-23 at 10:57 +0200, Linus Walleij wrote: > > > On Mon, Aug 19, 2019 at 11:22 AM Mars Cheng <mars.cheng@mediatek.com> wrote: > > > > This does not explain what a "virtual GPIO" is in this > > > context, so please elaborate. What is this? Why does > > > it exist? What is it used for? > > > > > > GPIO is "general purpose input/output" and it is a > > > pretty rubbery category already as it is, so we need > > > to define our terms pretty strictly. > > > > > Virtual GPIO only used inside SOC and not being exported to outside SOC > > in MTK platform. Some modules use virtual GPIO as eint (e.g. pmic or > > usb). > > I would call that internal GPIOs, those are very real rails inside > the chip made with polysilicone so there is nothing "virtual" > about them. If the documentation for the chip calls them virtual > then explain in the driver that these are SoC-internal > lines so that everyone will get it. > Got it, I will add the info into the driver in v3 > Is the PMIC inside the SoC? I thought that was usually outside of it > in its own chip. > > But I suppose there could be some interface to it in the SoC and > then that interface has this EINT? > That's right. I use incorrect word. e.g. pmic interface inside the SOC (PMIF), not pmic... > > In MTK platform, external interrupt (EINT) and GPIO is 1-1 mapping and > > we can set GPIO as eint. > > But some modules use specific eint which doesn't have real GPIO pin. > > So we use virtual GPIO to map it. > > OK I get it I think... just put these comments into the code as well > so we understand when reading the code what is going on. Got it, will add the comments in v3. Thanks for reviewing. > > > > > + if (mtk_is_virt_gpio(hw, gpio)) > > > > + return 1; > > > > > > Why are "virtual GPIOs" always inputs? > > > > We set virtual GPIO as eint. > > It mean virtual GPIO only used inside SOC and not being exported to > > outside SOC. > > Are you saying that: > - "Virtual" GPIOs are always and only used for interrupts > - Since they are only used for interrupts, they are always inputs > > Then write that in a comment to the above change so we know > this context. > Yes, virtual GPIOs are always and only used for interrupts in mtk platform. I'll add the comments in v3. Thanks for reviewing > Yours, > Linus Walleij > > _______________________________________________ > Linux-mediatek mailing list > Linux-mediatek@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-mediatek
next prev parent reply index Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top 2019-08-19 9:21 [PATCHv2 00/11] Add basic SoC Support for Mediatek MT6779 SoC Mars Cheng 2019-08-19 9:21 ` [PATCH v2 01/11] dt-bindings: mediatek: add support for mt6779 reference board Mars Cheng 2019-08-23 15:50 ` Matthias Brugger 2019-08-19 9:21 ` [PATCH v2 02/11] dt-bindings: mtk-uart: add mt6779 uart bindings Mars Cheng 2019-08-23 15:47 ` Matthias Brugger 2019-08-19 9:21 ` [PATCH v2 03/11] dt-bindings: irq: mtk,sysirq: add support for mt6779 Mars Cheng 2019-08-23 8:51 ` Linus Walleij 2019-08-23 15:51 ` Matthias Brugger 2019-08-23 15:44 ` Matthias Brugger 2019-08-27 16:50 ` Rob Herring 2019-08-19 9:21 ` [PATCH v2 04/11] pinctrl: mediatek: update pinmux definitions " Mars Cheng 2019-08-23 15:53 ` Matthias Brugger 2020-01-02 4:04 ` Hanks Chen 2019-08-19 9:21 ` [PATCH v2 05/11] pinctrl: mediatek: avoid virtual gpio trying to set reg Mars Cheng 2019-08-23 8:57 ` Linus Walleij 2019-12-22 13:52 ` Hanks Chen 2020-01-07 10:20 ` Linus Walleij 2020-01-08 11:27 ` Hanks Chen [this message] 2019-08-19 9:21 ` [PATCH v2 06/11] pinctrl: mediatek: add pinctrl support for MT6779 SoC Mars Cheng [not found] ` <CAGp9LzoVwNxY8Q3G4hxpa7=orsEox+J0mNamag70wyjrGvDiZw@mail.gmail.com> 2019-08-23 8:59 ` Linus Walleij 2019-08-19 9:21 ` [PATCH v2 07/11] pinctrl: mediatek: add mt6779 eint support Mars Cheng 2019-08-22 18:13 ` Sean Wang 2019-08-19 9:21 ` [PATCH v2 08/11] dt-bindings: mediatek: bindings for MT6779 clk Mars Cheng 2019-08-27 16:52 ` Rob Herring 2019-09-10 14:53 ` Stephen Boyd 2019-08-19 9:21 ` [PATCH v2 09/11] clk: mediatek: Add dt-bindings for MT6779 clocks Mars Cheng 2019-08-27 16:53 ` Rob Herring 2019-09-10 14:53 ` Stephen Boyd 2019-08-19 9:21 ` [PATCH v2 10/11] clk: mediatek: Add MT6779 clock support Mars Cheng 2019-09-10 14:53 ` Stephen Boyd 2019-08-19 9:21 ` [PATCH v2 11/11] arm64: dts: add dts nodes for MT6779 Mars Cheng 2019-08-19 9:40 ` Marc Zyngier 2019-08-19 11:42 ` Mars Cheng 2019-08-19 12:07 ` Marc Zyngier 2019-08-22 0:46 ` Mars Cheng 2019-08-23 16:13 ` Matthias Brugger
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=1578482850.7554.18.camel@mtkswgap22 \ --to=hanks.chen@mediatek.com \ --cc=cc.hwang@mediatek.com \ --cc=devicetree@vger.kernel.org \ --cc=linus.walleij@linaro.org \ --cc=linux-clk@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-mediatek@lists.infradead.org \ --cc=loda.chou@mediatek.com \ --cc=marc.zyngier@arm.com \ --cc=mars.cheng@mediatek.com \ --cc=matthias.bgg@gmail.com \ --cc=robh@kernel.org \ --cc=sboyd@kernel.org \ --cc=sean.wang@kernel.org \ --cc=wendell.lin@mediatek.com \ --cc=wsd_upstream@mediatek.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: link
Linux-Clk Archive on lore.kernel.org Archives are clonable: git clone --mirror https://lore.kernel.org/linux-clk/0 linux-clk/git/0.git # If you have public-inbox 1.1+ installed, you may # initialize and index your mirror using the following commands: public-inbox-init -V2 linux-clk linux-clk/ https://lore.kernel.org/linux-clk \ linux-clk@vger.kernel.org public-inbox-index linux-clk Example config snippet for mirrors Newsgroup available over NNTP: nntp://nntp.lore.kernel.org/org.kernel.vger.linux-clk AGPL code for this site: git clone https://public-inbox.org/public-inbox.git