Hi Christian,
On Sat, May 19, 2018 at 11:18:53AM +0200, Christian Lamparter wrote:
> On Friday, May 18, 2018 4:30:55 AM CEST Manivannan Sadhasivam wrote:
> > Add gpio support to pinctrl driver for Actions Semi S900 SoC.
> >
> > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasi...@linaro.org>
> > ---
> > [...]
> > +static int owl_gpio_init(struct owl_pinctrl *pctrl)
> > +{
> > + struct gpio_chip *chip;
> > + int ret;
> > +
> > + chip = &pctrl->chip;
> > + chip->base = -1;
> > + chip->ngpio = pctrl->soc->ngpios;
> > + chip->label = dev_name(pctrl->dev);
> > + chip->parent = pctrl->dev;
> > + chip->owner = THIS_MODULE;
> > + chip->of_node = pctrl->dev->of_node;
> > +
> > + ret = gpiochip_add_data(&pctrl->chip, pctrl);
> > + if (ret) {
> > + dev_err(pctrl->dev, "failed to register gpiochip\n");
> > + return ret;
> > + }
> > +
> > + ret = gpiochip_add_pin_range(&pctrl->chip, dev_name(pctrl->dev),
> > + 0, 0, chip->ngpio);
> > + if (ret) {
> > + dev_err(pctrl->dev, "failed to add pin range\n");
> > + gpiochip_remove(&pctrl->chip);
> > + return ret;
> > + }
> > +
> gpiochip_add_pin_range()? That's not going to work with gpio-hogs.
>
Hmmm. Just looked into the gpio-hog mechanism and the patch you have
implemented for MSM driver. I agree with you on replacing
gpiochip_add_pin_range() with gpio-ranges property. But I'm curious
whether we should document it somewhere or not (probably in [1]).
Anyway I will send the v2 incorporating your suggestion.
Thanks,
Mani
[1] Documentation/devicetree/bindings/gpio/gpio.txt
> But, you can easily test this. Just add a gpio-hog [0]
> ( Section 2. gpio-controller nodes) into the Devicetree's
> pinctrl node.
>
> something like: (No idea if GPIO1 is already used, but any free
> gpio will do)
> | [...]
> | pinctrl@e01b0000 {
> | compatible = "actions,s900-pinctrl";
> | reg = <0x0 0xe01b0000 0x0 0x1000>;
> | clocks = <&cmu CLK_GPIO>;
> | gpio-controller;
> | #gpio-cells = <2>;
> |
> | line_b {
> | gpio-hog;
> | gpios = <1 GPIO_ACTIVE_HIGH>;
> | output-low;
> | line-name = "foo-bar-gpio";
> | };
> | };
>
> The pinctrl probe will fail. You can fix this by
> replacing the gpiochip_add_pin_range() and use
> the gpio-ranges [0] property to define the range.
>
> [0]
> <https://www.kernel.org/doc/Documentation/devicetree/bindings/gpio/gpio.txt>
>
>
>
