From: Linus Walleij <linus.walleij@linaro.org>
To: Mars Cheng <mars.cheng@mediatek.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>,
Rob Herring <robh@kernel.org>,
Marc Zyngier <marc.zyngier@arm.com>,
Stephen Boyd <sboyd@kernel.org>, Sean Wang <sean.wang@kernel.org>,
CC Hwang <cc.hwang@mediatek.com>,
Loda Chou <loda.chou@mediatek.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"moderated list:ARM/Mediatek SoC support"
<linux-mediatek@lists.infradead.org>,
"open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS"
<devicetree@vger.kernel.org>,
wsd_upstream@mediatek.com, mtk01761 <wendell.lin@mediatek.com>,
linux-clk <linux-clk@vger.kernel.org>
Subject: Re: [PATCH v2 05/11] pinctrl: mediatek: avoid virtual gpio trying to set reg
Date: Fri, 23 Aug 2019 10:57:03 +0200 [thread overview]
Message-ID: <CACRpkdZa_sQgvWC3ic0NxrVi9gS1cNTsV-wa-SDpA0e5kutBRw@mail.gmail.com> (raw)
In-Reply-To: <1566206502-4347-6-git-send-email-mars.cheng@mediatek.com>
On Mon, Aug 19, 2019 at 11:22 AM Mars Cheng <mars.cheng@mediatek.com> wrote:
> for virtual gpios, they should not do reg setting and
> should behave as expected for eint function.
>
> Signed-off-by: Mars Cheng <mars.cheng@mediatek.com>
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.
> +bool mtk_is_virt_gpio(struct mtk_pinctrl *hw, unsigned int gpio_n)
> +{
> + const struct mtk_pin_desc *desc;
> + bool virt_gpio = false;
> +
> + if (gpio_n >= hw->soc->npins)
> + return virt_gpio;
> +
> + desc = (const struct mtk_pin_desc *)&hw->soc->pins[gpio_n];
> +
> + if (desc->funcs &&
> + desc->funcs[desc->eint.eint_m].name == 0)
NULL check is done like this:
if (desc->funcs && !desc->funcs[desc->eint.eint_m].name)
> + virt_gpio = true;
So why is this GPIO "virtual" because it does not have
a name in the funcs table?
> @@ -278,6 +295,9 @@ static int mtk_xt_set_gpio_as_eint(void *data, unsigned long eint_n)
> if (err)
> return err;
>
> + if (mtk_is_virt_gpio(hw, gpio_n))
> + return 0;
So does this mean we always succeed in setting a GPIO as eint
if it is virtual? Why? Explanatory comment is needed.
> @@ -693,6 +693,9 @@ static int mtk_gpio_get_direction(struct gpio_chip *chip, unsigned int gpio)
> const struct mtk_pin_desc *desc;
> int value, err;
>
> + if (mtk_is_virt_gpio(hw, gpio))
> + return 1;
Why are "virtual GPIOs" always inputs?
Yours,
Linus Walleij
next prev parent reply other threads:[~2019-08-23 8:57 UTC|newest]
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 [this message]
2019-12-22 13:52 ` Hanks Chen
2020-01-07 10:20 ` Linus Walleij
2020-01-08 11:27 ` Hanks Chen
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
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