Subject: [PATCH v2 2/9] pinctrl: single: support gpio request and free

From: [email-masked] (Tony Lindgren)
Date: Mon, 22 Oct 2012 14:37:09 -0700

* Tony Lindgren <[email-masked]> [121022 13:29]:
> * Haojian Zhuang <[email-masked]> [121022 09:11]:
> > --- a/drivers/pinctrl/pinctrl-single.c
> > +++ b/drivers/pinctrl/pinctrl-single.c
> > @@ -28,8 +28,10 @@
> >  #define DRIVER_NAME			"pinctrl-single"
> >  #define PCS_MUX_PINS_NAME		"pinctrl-single,pins"
> >  #define PCS_MUX_BITS_NAME		"pinctrl-single,bits"
> > +#define PCS_GPIO_FUNC_NAME		"pinctrl-single,gpio-func"
> 
> I think we can now get rid of these defines, I initially added
> them as we had a bit hard time finding a suitable name for the
> driver. These are only used in one location, so let's not add
> new ones here.
> 
> >  static int pcs_request_gpio(struct pinctrl_dev *pctldev,
> > -			struct pinctrl_gpio_range *range, unsigned offset)
> > +			    struct pinctrl_gpio_range *range, unsigned pin)
> >  {
> > -	return -ENOTSUPP;
> > +	struct pcs_device *pcs = pinctrl_dev_get_drvdata(pctldev);
> > +	struct pcs_gpio_range *gpio = NULL;
> > +	int end, mux_bytes;
> > +	unsigned data;
> > +
> > +	gpio = container_of(range, struct pcs_gpio_range, range);
> > +	if (!gpio->func_en)
> > +		return 0;
> > +	end = range->pin_base + range->npins - 1;
> > +	if (pin < range->pin_base || pin > end) {
> > +		dev_err(pctldev->dev, "pin %d isn't in the range of "
> > +			"%d to %d\n", pin, range->pin_base, end);
> > +		return -EINVAL;
> > +	}
> > +	mux_bytes = pcs->width / BITS_PER_BYTE;
> > +	data = pcs_readl(pcs->base + pin * mux_bytes) & ~pcs->fmask;
> > +	data |= gpio->gpio_func;
> > +	pcs_writel(data, pcs->base + pin * mux_bytes);
> > +	return 0;
> >  }
> 
> I think I already commented on this one.. Is this safe if you don't
> have GPIOs configured? Or should you return -ENODEV in that case?

Oops also you should not use pcs_readl/pcs_writel in the driver
directly but use pcs_read instead as you can have register width other
than 32-bits.

Regards,

Tony