Commit 24efd94b authored by Linus Walleij's avatar Linus Walleij
Browse files

gpio: mmio: Make pin2mask() a private business 



The vtable call pin2mask() was introducing a vtable function call
in every gpiochip callback for a generic MMIO GPIO chip. This was
not exactly efficient. (Maybe link-time optimization could get rid of
it, I don't know.)

After removing all external calls into this API we can make it a
boolean flag in the struct gpio_chip call and sink the function into
the gpio-mmio driver yielding encapsulation and potential speedups.

Cc: Anton Vorontsov <anton@enomsg.org>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent b3222f71

drivers/gpio/gpio-mmio.c

+19 −26
Original line number Diff line number Diff line
@@ -126,20 +126,16 @@ static unsigned long bgpio_read32be(void __iomem *reg) 
	return ioread32be(reg);

}



static unsigned long bgpio_pin2mask(struct gpio_chip *gc, unsigned int pin)

static unsigned long bgpio_line2mask(struct gpio_chip *gc, unsigned int line)

{

	return BIT(pin);

}



static unsigned long bgpio_pin2mask_be(struct gpio_chip *gc,

				       unsigned int pin)

{

	return BIT(gc->bgpio_bits - 1 - pin);

	if (gc->be_bits)

		return BIT(gc->bgpio_bits - 1 - line);

	return BIT(line);

}



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

{

	unsigned long pinmask = gc->pin2mask(gc, gpio);

	unsigned long pinmask = bgpio_line2mask(gc, gpio);



	if (gc->bgpio_dir & pinmask)

		return !!(gc->read_reg(gc->reg_set) & pinmask);
@@ -149,7 +145,7 @@ static int bgpio_get_set(struct gpio_chip *gc, unsigned int gpio) 


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

{

	return !!(gc->read_reg(gc->reg_dat) & gc->pin2mask(gc, gpio));

	return !!(gc->read_reg(gc->reg_dat) & bgpio_line2mask(gc, gpio));

}



static void bgpio_set_none(struct gpio_chip *gc, unsigned int gpio, int val)
@@ -158,7 +154,7 @@ static void bgpio_set_none(struct gpio_chip *gc, unsigned int gpio, int val) 


static void bgpio_set(struct gpio_chip *gc, unsigned int gpio, int val)

{

	unsigned long mask = gc->pin2mask(gc, gpio);

	unsigned long mask = bgpio_line2mask(gc, gpio);

	unsigned long flags;



	spin_lock_irqsave(&gc->bgpio_lock, flags);
@@ -176,7 +172,7 @@ static void bgpio_set(struct gpio_chip *gc, unsigned int gpio, int val) 
static void bgpio_set_with_clear(struct gpio_chip *gc, unsigned int gpio,

				 int val)

{

	unsigned long mask = gc->pin2mask(gc, gpio);

	unsigned long mask = bgpio_line2mask(gc, gpio);



	if (val)

		gc->write_reg(gc->reg_set, mask);
@@ -186,7 +182,7 @@ static void bgpio_set_with_clear(struct gpio_chip *gc, unsigned int gpio, 


static void bgpio_set_set(struct gpio_chip *gc, unsigned int gpio, int val)

{

	unsigned long mask = gc->pin2mask(gc, gpio);

	unsigned long mask = bgpio_line2mask(gc, gpio);

	unsigned long flags;



	spin_lock_irqsave(&gc->bgpio_lock, flags);
@@ -216,9 +212,9 @@ static void bgpio_multiple_get_masks(struct gpio_chip *gc, 
			break;

		if (__test_and_clear_bit(i, mask)) {

			if (test_bit(i, bits))

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

				*set_mask |= bgpio_line2mask(gc, i);

			else

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

				*clear_mask |= bgpio_line2mask(gc, i);

		}

	}

}
@@ -294,7 +290,7 @@ static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio) 


	spin_lock_irqsave(&gc->bgpio_lock, flags);



	gc->bgpio_dir &= ~gc->pin2mask(gc, gpio);

	gc->bgpio_dir &= ~bgpio_line2mask(gc, gpio);

	gc->write_reg(gc->reg_dir, gc->bgpio_dir);



	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
@@ -305,7 +301,7 @@ static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio) 
static int bgpio_get_dir(struct gpio_chip *gc, unsigned int gpio)

{

	/* Return 0 if output, 1 of input */

	return !(gc->read_reg(gc->reg_dir) & gc->pin2mask(gc, gpio));

	return !(gc->read_reg(gc->reg_dir) & bgpio_line2mask(gc, gpio));

}



static int bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
@@ -316,7 +312,7 @@ static int bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val) 


	spin_lock_irqsave(&gc->bgpio_lock, flags);



	gc->bgpio_dir |= gc->pin2mask(gc, gpio);

	gc->bgpio_dir |= bgpio_line2mask(gc, gpio);

	gc->write_reg(gc->reg_dir, gc->bgpio_dir);



	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
@@ -330,7 +326,7 @@ static int bgpio_dir_in_inv(struct gpio_chip *gc, unsigned int gpio) 


	spin_lock_irqsave(&gc->bgpio_lock, flags);



	gc->bgpio_dir |= gc->pin2mask(gc, gpio);

	gc->bgpio_dir |= bgpio_line2mask(gc, gpio);

	gc->write_reg(gc->reg_dir, gc->bgpio_dir);



	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
@@ -346,7 +342,7 @@ static int bgpio_dir_out_inv(struct gpio_chip *gc, unsigned int gpio, int val) 


	spin_lock_irqsave(&gc->bgpio_lock, flags);



	gc->bgpio_dir &= ~gc->pin2mask(gc, gpio);

	gc->bgpio_dir &= ~bgpio_line2mask(gc, gpio);

	gc->write_reg(gc->reg_dir, gc->bgpio_dir);



	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
@@ -357,12 +353,11 @@ static int bgpio_dir_out_inv(struct gpio_chip *gc, unsigned int gpio, int val) 
static int bgpio_get_dir_inv(struct gpio_chip *gc, unsigned int gpio)

{

	/* Return 0 if output, 1 if input */

	return !!(gc->read_reg(gc->reg_dir) & gc->pin2mask(gc, gpio));

	return !!(gc->read_reg(gc->reg_dir) & bgpio_line2mask(gc, gpio));

}



static int bgpio_setup_accessors(struct device *dev,

				 struct gpio_chip *gc,

				 bool bit_be,

				 bool byte_be)

{
@@ -406,8 +401,6 @@ static int bgpio_setup_accessors(struct device *dev, 
		return -EINVAL;

	}



	gc->pin2mask = bit_be ? bgpio_pin2mask_be : bgpio_pin2mask;



	return 0;

}
@@ -531,8 +524,8 @@ int bgpio_init(struct gpio_chip *gc, struct device *dev, 
	if (ret)

		return ret;



	ret = bgpio_setup_accessors(dev, gc, flags & BGPIOF_BIG_ENDIAN,

				    flags & BGPIOF_BIG_ENDIAN_BYTE_ORDER);

	gc->be_bits = !!(flags & BGPIOF_BIG_ENDIAN);

	ret = bgpio_setup_accessors(dev, gc, flags & BGPIOF_BIG_ENDIAN_BYTE_ORDER);

	if (ret)

		return ret;

include/linux/gpio/driver.h

+4 −4
Original line number Diff line number Diff line
@@ -67,9 +67,9 @@ struct module; 
 *	registers.

 * @read_reg: reader function for generic GPIO

 * @write_reg: writer function for generic GPIO

 * @pin2mask: some generic GPIO controllers work with the big-endian bits

 *	notation, e.g. in a 8-bits register, GPIO7 is the least significant

 *	bit. This callback assigns the right bit mask.

 * @be_bits: if the generic GPIO has big endian bit order (bit 31 is representing

 *	line 0, bit 30 is line 1 ... bit 0 is line 31) this is set to true by the

 *	generic GPIO core. It is for internal housekeeping only.

 * @reg_dat: data (in) register for generic GPIO

 * @reg_set: output set register (out=high) for generic GPIO

 * @reg_clr: output clear register (out=low) for generic GPIO
@@ -151,7 +151,7 @@ struct gpio_chip { 
#if IS_ENABLED(CONFIG_GPIO_GENERIC)

	unsigned long (*read_reg)(void __iomem *reg);

	void (*write_reg)(void __iomem *reg, unsigned long data);

	unsigned long (*pin2mask)(struct gpio_chip *gc, unsigned int pin);

	bool be_bits;

	void __iomem *reg_dat;

	void __iomem *reg_set;

	void __iomem *reg_clr;

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