Commit 73c4ceda authored by Rojhalat Ibrahim's avatar Rojhalat Ibrahim Committed by Linus Walleij
Browse files

gpio-generic: add bgpio_set_multiple functions 



Add set_multiple functions to the generic driver for memory-mapped GPIO
controllers to improve performance when setting multiple outputs
simultaneously.

Signed-off-by: default avatarRojhalat Ibrahim <imr@rtschenk.de>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent 51385858

drivers/gpio/gpio-generic.c

+76 −0
Original line number Diff line number Diff line
@@ -190,6 +190,79 @@ static void bgpio_set_set(struct gpio_chip *gc, unsigned int gpio, int val) 
	spin_unlock_irqrestore(&bgc->lock, flags);

}



static void bgpio_multiple_get_masks(struct bgpio_chip *bgc,

				     unsigned long *mask, unsigned long *bits,

				     unsigned long *set_mask,

				     unsigned long *clear_mask)

{

	int i;



	*set_mask = 0;

	*clear_mask = 0;



	for (i = 0; i < bgc->bits; i++) {

		if (*mask == 0)

			break;

		if (__test_and_clear_bit(i, mask)) {

			if (test_bit(i, bits))

				*set_mask |= bgc->pin2mask(bgc, i);

			else

				*clear_mask |= bgc->pin2mask(bgc, i);

		}

	}

}



static void bgpio_set_multiple_single_reg(struct bgpio_chip *bgc,

					  unsigned long *mask,

					  unsigned long *bits,

					  void __iomem *reg)

{

	unsigned long flags;

	unsigned long set_mask, clear_mask;



	spin_lock_irqsave(&bgc->lock, flags);



	bgpio_multiple_get_masks(bgc, mask, bits, &set_mask, &clear_mask);



	bgc->data |= set_mask;

	bgc->data &= ~clear_mask;



	bgc->write_reg(reg, bgc->data);



	spin_unlock_irqrestore(&bgc->lock, flags);

}



static void bgpio_set_multiple(struct gpio_chip *gc, unsigned long *mask,

			       unsigned long *bits)

{

	struct bgpio_chip *bgc = to_bgpio_chip(gc);



	bgpio_set_multiple_single_reg(bgc, mask, bits, bgc->reg_dat);

}



static void bgpio_set_multiple_set(struct gpio_chip *gc, unsigned long *mask,

				   unsigned long *bits)

{

	struct bgpio_chip *bgc = to_bgpio_chip(gc);



	bgpio_set_multiple_single_reg(bgc, mask, bits, bgc->reg_set);

}



static void bgpio_set_multiple_with_clear(struct gpio_chip *gc,

					  unsigned long *mask,

					  unsigned long *bits)

{

	struct bgpio_chip *bgc = to_bgpio_chip(gc);

	unsigned long set_mask, clear_mask;



	bgpio_multiple_get_masks(bgc, mask, bits, &set_mask, &clear_mask);



	if (set_mask)

		bgc->write_reg(bgc->reg_set, set_mask);

	if (clear_mask)

		bgc->write_reg(bgc->reg_clr, clear_mask);

}



static int bgpio_simple_dir_in(struct gpio_chip *gc, unsigned int gpio)

{

	return 0;
@@ -354,11 +427,14 @@ static int bgpio_setup_io(struct bgpio_chip *bgc, 
		bgc->reg_set = set;

		bgc->reg_clr = clr;

		bgc->gc.set = bgpio_set_with_clear;

		bgc->gc.set_multiple = bgpio_set_multiple_with_clear;

	} else if (set && !clr) {

		bgc->reg_set = set;

		bgc->gc.set = bgpio_set_set;

		bgc->gc.set_multiple = bgpio_set_multiple_set;

	} else {

		bgc->gc.set = bgpio_set;

		bgc->gc.set_multiple = bgpio_set_multiple;

	}



	bgc->gc.get = bgpio_get;