Re: [PATCH v2 00/16] gpio: Tight IRQ chip integration and banked infrastructure

From: Linus Walleij
Date: Mon Oct 02 2017 - 03:55:30 EST


On Thu, Sep 28, 2017 at 4:22 PM, Grygorii Strashko
<grygorii.strashko@xxxxxx> wrote:

> Sry, but I do not agree with this series.
> - no prof that it can be re-used by other drivers than tegra
> (at least I do not see reasons to re-use it for any TI drivers)

This is not necessarily a blocker if it can be shown that others than
TI/OMAP can reuse it.

I've looked at things like the imagination pistachio:

pinctrl@18101C00 {
compatible = "img,pistachio-system-pinctrl";
reg = <0x18101C00 0x400>;

gpio0: gpio0 {
interrupts = <GIC_SHARED 71 IRQ_TYPE_LEVEL_HIGH>;

gpio-controller;
#gpio-cells = <2>;

interrupt-controller;
#interrupt-cells = <2>;
};

...

gpio5: gpio5 {
interrupts = <GIC_SHARED 76 IRQ_TYPE_LEVEL_HIGH>;

gpio-controller;
#gpio-cells = <2>;

interrupt-controller;
#interrupt-cells = <2>;
};

This looks like a clear candidate.
CC: to Andrew Bresticker, can you look into this?

Another example would be gpio-tz1090, notably with interrupt optional:

gpios: gpio-controller@02005800 {
#address-cells = <1>;
#size-cells = <0>;
compatible = "img,tz1090-gpio";
reg = <0x02005800 0x90>;

/* bank 0 with an interrupt */
gpios0: bank@0 {
#gpio-cells = <2>;
#interrupt-cells = <2>;
reg = <0>;
interrupts = <13 IRQ_TYPE_LEVEL_HIGH>;
gpio-controller;
gpio-ranges = <&pinctrl 0 0 30>;
interrupt-controller;
};

/* bank 2 without interrupt */
gpios2: bank@2 {
#gpio-cells = <2>;
reg = <2>;
gpio-controller;
gpio-ranges = <&pinctrl 0 60 30>;
};
};

CC to James Hogan to look at the series from this perspective.

A third is gpio-mxs.c:

pinctrl@80018000 {
compatible = "fsl,imx28-pinctrl", "simple-bus";
reg = <0x80018000 2000>;

gpio0: gpio@0 {
compatible = "fsl,imx28-gpio";
interrupts = <127>;
gpio-controller;
#gpio-cells = <2>;
interrupt-controller;
#interrupt-cells = <2>;
};

gpio1: gpio@1 {
compatible = "fsl,imx28-gpio";
interrupts = <126>;
gpio-controller;
#gpio-cells = <2>;
interrupt-controller;
#interrupt-cells = <2>;
};

gpio2: gpio@2 {
compatible = "fsl,imx28-gpio";
interrupts = <125>;
gpio-controller;
#gpio-cells = <2>;
interrupt-controller;
#interrupt-cells = <2>;
};
(...)

CC to Shawn Guo to look into this.

So in short I think there can be others that can make good use of this
infrastructure.

> - all GPIO IRQs mapped statically

This really needs to be fixed.

> - irq->map[offset + j] = irq->parents[parent]; holds IRQs for all pins
> which is waste of memory
> - DT binding changes not documented and no DT examples
> - below is ugly ;)
> + bank = (spec[0] >> gc->of_gpio_bank_mask) & gc->of_gpio_bank_shift;
> + pin = (spec[0] >> gc->of_gpio_pin_mask) & gc->of_gpio_pin_shift;

These should be fixable quite easily I think. Thierry?

Yours,
Linus Walleij