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Commit d3a7b9e3 authored by Tomasz Figa's avatar Tomasz Figa Committed by Linus Walleij
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pinctrl: samsung: Use one GPIO chip per pin bank 



This patch modifies the pinctrl-samsung driver to register one GPIO chip
per pin bank, instead of a single chip for all pin banks of the
controller.

It simplifies GPIO accesses a lot (constant time instead of looping
through the list of banks to find the right one) and should have a good
effect on performance of any bit-banging driver.

In addition it allows to reference GPIO pins by a phandle to the bank
node and a local pin offset inside of the bank (similar to previous
gpiolib driver), which is more clear and readable than using indices
relative to the whole pin controller.

Example:
	device {
		/* ... */
		gpios = <&gpk0 4 0>;
		/* ... */
	};

Signed-off-by: default avatarTomasz Figa <t.figa@samsung.com>
Reviewed-by: default avatarKyungmin Park <kyungmin.park@samsung.com>
Acked-by: default avatarThomas Abraham <thomas.abraham@linaro.org>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent 595be726

drivers/pinctrl/pinctrl-samsung.c

+73 −44
Original line number Diff line number Diff line
@@ -48,6 +48,11 @@ struct pin_config { 


static unsigned int pin_base = 0;



static inline struct samsung_pin_bank *gc_to_pin_bank(struct gpio_chip *gc)

{

	return container_of(gc, struct samsung_pin_bank, gpio_chip);

}



/* check if the selector is a valid pin group selector */

static int samsung_get_group_count(struct pinctrl_dev *pctldev)

{
@@ -333,9 +338,12 @@ static int samsung_pinmux_gpio_set_direction(struct pinctrl_dev *pctldev, 
	void __iomem *reg;

	u32 data, pin_offset, mask, shift;



	bank = gc_to_pin_bank(range->gc);

	drvdata = pinctrl_dev_get_drvdata(pctldev);



	pin_to_reg_bank(drvdata, offset, &reg, &pin_offset, &bank);

	pin_offset = offset - bank->pin_base;

	reg = drvdata->virt_base + bank->pctl_offset;



	mask = (1 << bank->func_width) - 1;

	shift = pin_offset * bank->func_width;
@@ -469,17 +477,16 @@ static struct pinconf_ops samsung_pinconf_ops = { 
/* gpiolib gpio_set callback function */

static void samsung_gpio_set(struct gpio_chip *gc, unsigned offset, int value)

{

	struct samsung_pin_bank *bank = gc_to_pin_bank(gc);

	void __iomem *reg;

	u32 pin_offset, data;

	struct samsung_pinctrl_drv_data *drvdata;

	u32 data;



	drvdata = dev_get_drvdata(gc->dev);

	reg = bank->drvdata->virt_base + bank->pctl_offset;



	pin_to_reg_bank(drvdata, offset, &reg, &pin_offset, NULL);

	data = readl(reg + DAT_REG);

	data &= ~(1 << pin_offset);

	data &= ~(1 << offset);

	if (value)

		data |= 1 << pin_offset;

		data |= 1 << offset;

	writel(data, reg + DAT_REG);

}
@@ -487,14 +494,13 @@ static void samsung_gpio_set(struct gpio_chip *gc, unsigned offset, int value) 
static int samsung_gpio_get(struct gpio_chip *gc, unsigned offset)

{

	void __iomem *reg;

	u32 pin_offset, data;

	struct samsung_pinctrl_drv_data *drvdata;

	u32 data;

	struct samsung_pin_bank *bank = gc_to_pin_bank(gc);



	drvdata = dev_get_drvdata(gc->dev);

	reg = bank->drvdata->virt_base + bank->pctl_offset;



	pin_to_reg_bank(drvdata, offset, &reg, &pin_offset, NULL);

	data = readl(reg + DAT_REG);

	data >>= pin_offset;

	data >>= offset;

	data &= 1;

	return data;

}
@@ -724,12 +730,16 @@ static int __init samsung_pinctrl_register(struct platform_device *pdev, 
		return -EINVAL;

	}



	drvdata->grange.name = "samsung-pctrl-gpio-range";

	drvdata->grange.id = 0;

	drvdata->grange.base = drvdata->ctrl->base;

	drvdata->grange.npins = drvdata->ctrl->nr_pins;

	drvdata->grange.gc = drvdata->gc;

	pinctrl_add_gpio_range(drvdata->pctl_dev, &drvdata->grange);

	for (bank = 0; bank < drvdata->ctrl->nr_banks; ++bank) {

		pin_bank = &drvdata->ctrl->pin_banks[bank];

		pin_bank->grange.name = pin_bank->name;

		pin_bank->grange.id = bank;

		pin_bank->grange.pin_base = pin_bank->pin_base;

		pin_bank->grange.base = pin_bank->gpio_chip.base;

		pin_bank->grange.npins = pin_bank->gpio_chip.ngpio;

		pin_bank->grange.gc = &pin_bank->gpio_chip;

		pinctrl_add_gpio_range(drvdata->pctl_dev, &pin_bank->grange);

	}



	ret = samsung_pinctrl_parse_dt(pdev, drvdata);

	if (ret) {
@@ -740,50 +750,69 @@ static int __init samsung_pinctrl_register(struct platform_device *pdev, 
	return 0;

}



static const struct gpio_chip samsung_gpiolib_chip = {

	.set = samsung_gpio_set,

	.get = samsung_gpio_get,

	.direction_input = samsung_gpio_direction_input,

	.direction_output = samsung_gpio_direction_output,

	.owner = THIS_MODULE,

};



/* register the gpiolib interface with the gpiolib subsystem */

static int __init samsung_gpiolib_register(struct platform_device *pdev,

				struct samsung_pinctrl_drv_data *drvdata)

{

	struct samsung_pin_ctrl *ctrl = drvdata->ctrl;

	struct samsung_pin_bank *bank = ctrl->pin_banks;

	struct gpio_chip *gc;

	int ret;

	int i;



	gc = devm_kzalloc(&pdev->dev, sizeof(*gc), GFP_KERNEL);

	if (!gc) {

		dev_err(&pdev->dev, "mem alloc for gpio_chip failed\n");

		return -ENOMEM;

	}

	for (i = 0; i < ctrl->nr_banks; ++i, ++bank) {

		bank->gpio_chip = samsung_gpiolib_chip;



	drvdata->gc = gc;

	gc->base = drvdata->ctrl->base;

	gc->ngpio = drvdata->ctrl->nr_pins;

		gc = &bank->gpio_chip;

		gc->base = ctrl->base + bank->pin_base;

		gc->ngpio = bank->nr_pins;

		gc->dev = &pdev->dev;

	gc->set = samsung_gpio_set;

	gc->get = samsung_gpio_get;

	gc->direction_input = samsung_gpio_direction_input;

	gc->direction_output = samsung_gpio_direction_output;

	gc->label = drvdata->ctrl->label;

	gc->owner = THIS_MODULE;

		gc->of_node = bank->of_node;

		gc->label = bank->name;



		ret = gpiochip_add(gc);

		if (ret) {

		dev_err(&pdev->dev, "failed to register gpio_chip %s, error "

					"code: %d\n", gc->label, ret);

		return ret;

			dev_err(&pdev->dev, "failed to register gpio_chip %s, error code: %d\n",

							gc->label, ret);

			goto fail;

		}

	}



	return 0;



fail:

	for (--i, --bank; i >= 0; --i, --bank)

		if (gpiochip_remove(&bank->gpio_chip))

			dev_err(&pdev->dev, "gpio chip %s remove failed\n",

							bank->gpio_chip.label);

	return ret;

}



/* unregister the gpiolib interface with the gpiolib subsystem */

static int __init samsung_gpiolib_unregister(struct platform_device *pdev,

				struct samsung_pinctrl_drv_data *drvdata)

{

	int ret = gpiochip_remove(drvdata->gc);

	if (ret) {

	struct samsung_pin_ctrl *ctrl = drvdata->ctrl;

	struct samsung_pin_bank *bank = ctrl->pin_banks;

	int ret = 0;

	int i;



	for (i = 0; !ret && i < ctrl->nr_banks; ++i, ++bank)

		ret = gpiochip_remove(&bank->gpio_chip);



	if (ret)

		dev_err(&pdev->dev, "gpio chip remove failed\n");



	return ret;

}

	return 0;

}



static const struct of_device_id samsung_pinctrl_dt_match[];

drivers/pinctrl/pinctrl-samsung.h

+6 −5
Original line number Diff line number Diff line
@@ -23,6 +23,8 @@ 
#include <linux/pinctrl/consumer.h>

#include <linux/pinctrl/machine.h>



#include <linux/gpio.h>



/* register offsets within a pin bank */

#define DAT_REG		0x4

#define PUD_REG		0x8
@@ -113,6 +115,8 @@ struct samsung_pinctrl_drv_data; 
 * @of_node: OF node of the bank.

 * @drvdata: link to controller driver data

 * @irq_domain: IRQ domain of the bank.

 * @gpio_chip: GPIO chip of the bank.

 * @grange: linux gpio pin range supported by this bank.

 */

struct samsung_pin_bank {

	u32		pctl_offset;
@@ -129,6 +133,8 @@ struct samsung_pin_bank { 
	struct device_node *of_node;

	struct samsung_pinctrl_drv_data *drvdata;

	struct irq_domain *irq_domain;

	struct gpio_chip gpio_chip;

	struct pinctrl_gpio_range grange;

};



/**
@@ -186,8 +192,6 @@ struct samsung_pin_ctrl { 
 * @nr_groups: number of such pin groups.

 * @pmx_functions: list of pin functions available to the driver.

 * @nr_function: number of such pin functions.

 * @gc: gpio_chip instance registered with gpiolib.

 * @grange: linux gpio pin range supported by this controller.

 */

struct samsung_pinctrl_drv_data {

	void __iomem			*virt_base;
@@ -204,9 +208,6 @@ struct samsung_pinctrl_drv_data { 
	unsigned int			nr_functions;



	struct irq_domain		*wkup_irqd;



	struct gpio_chip		*gc;

	struct pinctrl_gpio_range	grange;

};



/**