Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq

From	Linus Walleij <linus.walleij@linaro.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq
Date	2016-10-25 20:20 +0200
Message-ID	<sweul-Lo-3@gated-at.bofh.it> (permalink)
References	(5 earlier) <sw7jd-4nV-39@gated-at.bofh.it> <sw9El-641-1@gated-at.bofh.it> <swa7n-6eB-9@gated-at.bofh.it> <swaTM-6Oo-9@gated-at.bofh.it> <swbd8-6Vq-27@gated-at.bofh.it>
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On Tue, Oct 25, 2016 at 4:47 PM, Marc Zyngier <marc.zyngier@arm.com> wrote:
> On 25/10/16 15:22, Jerome Brunet wrote:

>> There is a few problems to guarantee that gpio == hwirq.
>> 1. We have 2 instances of pinctrl, to guarantee that the linux gpio
>> number == hwirq, we would have to guarantee the order in which they are
>> probed. At least this my understanding
>
> Maybe I wasn't clear enough, and my use of gpio is probably wrong. So
> Linux has a gpio number, which is obviously an abstract number (just
> like the Linux irq number). But the pad number, in the context of given
> SoC, is constant. So we have:
>
>         pad->gpio
>         hwirq->irq
>
> Why can't you have pad == hwirq, always? This is already what you have
> in the irqchip driver. This would simplify a lot of things.

My thought as well.

We usually refer to the local numberspace on the GPIO controller
as "offsets", so line offsets 0...31 on a gpiochip with 31 lines.

The ngpio in struct gpio_chip is the number of lines on that controller,
and should nominally map 1:1 to hwirq sources.

Yours,
Linus Walleij

Thread

[PATCH 4/9] pinctrl: meson: allow gpio to request irq Jerome Brunet <jbrunet@baylibre.com> - 2016-10-19 17:30 +0200
  Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq Linus Walleij <linus.walleij@linaro.org> - 2016-10-20 21:30 +0200
    Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq Jerome Brunet <jbrunet@baylibre.com> - 2016-10-21 11:10 +0200
      Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq Linus Walleij <linus.walleij@linaro.org> - 2016-10-25 11:20 +0200
        Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq Marc Zyngier <marc.zyngier@arm.com> - 2016-10-25 12:40 +0200
          Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq Jerome Brunet <jbrunet@baylibre.com> - 2016-10-25 15:10 +0200
            Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq Marc Zyngier <marc.zyngier@arm.com> - 2016-10-25 15:40 +0200
              Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq Jerome Brunet <jbrunet@baylibre.com> - 2016-10-25 16:30 +0200
                Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq Marc Zyngier <marc.zyngier@arm.com> - 2016-10-25 16:50 +0200
                Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq Jerome Brunet <jbrunet@baylibre.com> - 2016-10-25 17:40 +0200
                Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq Linus Walleij <linus.walleij@linaro.org> - 2016-10-25 20:30 +0200
                Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq Jerome Brunet <jbrunet@baylibre.com> - 2016-10-26 16:30 +0200
                Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq Linus Walleij <linus.walleij@linaro.org> - 2016-10-26 16:40 +0200
                Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq Kevin Hilman <khilman@baylibre.com> - 2016-10-26 18:00 +0200
                Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq Linus Walleij <linus.walleij@linaro.org> - 2016-10-25 20:20 +0200
                Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq Jerome Brunet <jbrunet@baylibre.com> - 2016-10-26 16:30 +0200
                Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq Linus Walleij <linus.walleij@linaro.org> - 2016-10-26 16:50 +0200
        Re: [PATCH 4/9] pinctrl: meson: allow gpio to request irq Thomas Gleixner <tglx@linutronix.de> - 2016-10-25 12:50 +0200

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