On Mon, Mar 6, 2023 at 5:39 PM Bartosz Golaszewski <brgl@xxxxxxxx> wrote:
>
> On Thu, Mar 2, 2023 at 1:53 PM Keguang Zhang <keguang.zhang@xxxxxxxxx> wrote:
> >
> > This patch adds DT support for Loongson-1 GPIO driver.
> >
> > Signed-off-by: Keguang Zhang <keguang.zhang@xxxxxxxxx>
> > ---
> > V1 -> V2: Let gpiolib parse ngpios property
> > Remove unnecessary alias id parsing
> > Remove superfluous initialization done by bgpio_init()
> > Add MODULE_DEVICE_TABLE()
> > Other minor fixes
> > ---
> > drivers/gpio/gpio-loongson1.c | 19 ++++++++++++++++---
> > 1 file changed, 16 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/gpio/gpio-loongson1.c b/drivers/gpio/gpio-loongson1.c
> > index 3ac9e49e7efb..94ac0ccb450f 100644
> > --- a/drivers/gpio/gpio-loongson1.c
> > +++ b/drivers/gpio/gpio-loongson1.c
> > @@ -68,25 +68,38 @@ static int ls1x_gpio_probe(struct platform_device *pdev)
> > ls1x_gc->gc.owner = THIS_MODULE;
> > ls1x_gc->gc.request = ls1x_gpio_request;
> > ls1x_gc->gc.free = ls1x_gpio_free;
> > - ls1x_gc->gc.base = pdev->id * 32;
> > + /*
> > + * Clear ngpio to let gpiolib get the correct number
> > + * by reading ngpios property
> > + */
> > + ls1x_gc->gc.ngpio = 0;
> >
>
> Who could have set it before and why would this information need to be
> unconditionally discarded?
>
'ngpio' has been set to 32 by bgpio_init().
But this is incorrect for LS1B who has different number of GPIOs for each group.
To get the right number, I have to discard this default value to let
gpiolib parse 'ngpios' property.
> Bart
>
> > ret = devm_gpiochip_add_data(dev, &ls1x_gc->gc, ls1x_gc);
> > if (ret)
> > goto err;
> >
> > platform_set_drvdata(pdev, ls1x_gc);
> > - dev_info(dev, "Loongson1 GPIO driver registered\n");
> > +
> > + dev_info(dev, "GPIO controller registered with %d pins\n",
> > + ls1x_gc->gc.ngpio);
> >
> > return 0;
> > err:
> > - dev_err(dev, "failed to register GPIO device\n");
> > + dev_err(dev, "failed to register GPIO controller\n");
> > return ret;
> > }
> >
> > +static const struct of_device_id ls1x_gpio_dt_ids[] = {
> > + { .compatible = "loongson,ls1x-gpio" },
> > + { /* sentinel */ }
> > +};
> > +MODULE_DEVICE_TABLE(of, ls1x_gpio_dt_ids);
> > +
> > static struct platform_driver ls1x_gpio_driver = {
> > .probe = ls1x_gpio_probe,
> > .driver = {
> > .name = "ls1x-gpio",
> > + .of_match_table = ls1x_gpio_dt_ids,
> > },
> > };
> >
> > --
> > 2.34.1
> >
--
Best regards,
Kelvin Cheung
