Commit 2145ba37 authored by Linus Walleij's avatar Linus Walleij Committed by Bartosz Golaszewski
Browse files

gpio: mmio: Add flag for calling pinctrl back-end 



It turns out that with this flag we can switch over an entire
driver to use gpio-mmio instead of a bunch of custom code,
also providing get/set_multiple() to it in the process, so it
seems like a reasonable feature to add.

The generic pin control backend requires us to call the
gpiochip_generic_request(), gpiochip_generic_free(),
pinctrl_gpio_direction_output() and pinctrl_gpio_direction_input()
callbacks, so if the new flag for a pin control back-end
is set, we make sure these functions get called as
expected.

Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20250219-vf610-mmio-v3-1-588b64f0b689@linaro.org


Signed-off-by: default avatarBartosz Golaszewski <bartosz.golaszewski@linaro.org>
parent 45af02f0

drivers/gpio/gpio-mmio.c

+29 −8
Original line number Diff line number Diff line
@@ -49,6 +49,7 @@ o ` ~~~~\___/~~~~ ` controller in FPGA is ,.` 
#include <linux/log2.h>

#include <linux/mod_devicetable.h>

#include <linux/module.h>

#include <linux/pinctrl/consumer.h>

#include <linux/platform_device.h>

#include <linux/property.h>

#include <linux/slab.h>
@@ -323,9 +324,20 @@ static void bgpio_set_multiple_with_clear(struct gpio_chip *gc, 
		gc->write_reg(gc->reg_clr, clear_mask);

}



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

static int bgpio_dir_return(struct gpio_chip *gc, unsigned int gpio, bool dir_out)

{

	if (!gc->bgpio_pinctrl)

		return 0;



	if (dir_out)

		return pinctrl_gpio_direction_output(gc, gpio);

	else

		return pinctrl_gpio_direction_input(gc, gpio);

}



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

{

	return bgpio_dir_return(gc, gpio, false);

}



static int bgpio_dir_out_err(struct gpio_chip *gc, unsigned int gpio,
@@ -339,7 +351,7 @@ static int bgpio_simple_dir_out(struct gpio_chip *gc, unsigned int gpio, 
{

	gc->set(gc, gpio, val);



	return 0;

	return bgpio_dir_return(gc, gpio, true);

}



static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
@@ -357,7 +369,7 @@ static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio) 


	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);



	return 0;

	return bgpio_dir_return(gc, gpio, false);

}



static int bgpio_get_dir(struct gpio_chip *gc, unsigned int gpio)
@@ -403,7 +415,7 @@ static int bgpio_dir_out_dir_first(struct gpio_chip *gc, unsigned int gpio, 
{

	bgpio_dir_out(gc, gpio, val);

	gc->set(gc, gpio, val);

	return 0;

	return bgpio_dir_return(gc, gpio, true);

}



static int bgpio_dir_out_val_first(struct gpio_chip *gc, unsigned int gpio,
@@ -411,7 +423,7 @@ static int bgpio_dir_out_val_first(struct gpio_chip *gc, unsigned int gpio, 
{

	gc->set(gc, gpio, val);

	bgpio_dir_out(gc, gpio, val);

	return 0;

	return bgpio_dir_return(gc, gpio, true);

}



static int bgpio_setup_accessors(struct device *dev,
@@ -562,10 +574,13 @@ static int bgpio_setup_direction(struct gpio_chip *gc, 


static int bgpio_request(struct gpio_chip *chip, unsigned gpio_pin)

{

	if (gpio_pin < chip->ngpio)

		return 0;



	if (gpio_pin >= chip->ngpio)

		return -EINVAL;



	if (chip->bgpio_pinctrl)

		return gpiochip_generic_request(chip, gpio_pin);



	return 0;

}



/**
@@ -632,6 +647,12 @@ int bgpio_init(struct gpio_chip *gc, struct device *dev, 
	if (ret)

		return ret;



	if (flags & BGPIOF_PINCTRL_BACKEND) {

		gc->bgpio_pinctrl = true;

		/* Currently this callback is only used for pincontrol */

		gc->free = gpiochip_generic_free;

	}



	gc->bgpio_data = gc->read_reg(gc->reg_dat);

	if (gc->set == bgpio_set_set &&

			!(flags & BGPIOF_UNREADABLE_REG_SET))

include/linux/gpio/driver.h

+3 −0
Original line number Diff line number Diff line
@@ -397,6 +397,7 @@ struct gpio_irq_chip { 
 * @reg_dir_in: direction in setting register for generic GPIO

 * @bgpio_dir_unreadable: indicates that the direction register(s) cannot

 *	be read and we need to rely on out internal state tracking.

 * @bgpio_pinctrl: the generic GPIO uses a pin control backend.

 * @bgpio_bits: number of register bits used for a generic GPIO i.e.

 *	<register width> * 8

 * @bgpio_lock: used to lock chip->bgpio_data. Also, this is needed to keep
@@ -481,6 +482,7 @@ struct gpio_chip { 
	void __iomem *reg_dir_out;

	void __iomem *reg_dir_in;

	bool bgpio_dir_unreadable;

	bool bgpio_pinctrl;

	int bgpio_bits;

	raw_spinlock_t bgpio_lock;

	unsigned long bgpio_data;
@@ -721,6 +723,7 @@ int bgpio_init(struct gpio_chip *gc, struct device *dev, 
#define BGPIOF_READ_OUTPUT_REG_SET	BIT(4) /* reg_set stores output value */

#define BGPIOF_NO_OUTPUT		BIT(5) /* only input */

#define BGPIOF_NO_SET_ON_INPUT		BIT(6)

#define BGPIOF_PINCTRL_BACKEND		BIT(7) /* Call pinctrl direction setters */



#ifdef CONFIG_GPIOLIB_IRQCHIP

int gpiochip_irqchip_add_domain(struct gpio_chip *gc,