drivers/gpio/sunxi_gpio.c

/*
 * (C) Copyright 2012 Henrik Nordstrom <henrik@henriknordstrom.net>
 *
 * Based on earlier arch/arm/cpu/armv7/sunxi/gpio.c:
 *
 * (C) Copyright 2007-2011
 * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
 * Tom Cubie <tangliang@allwinnertech.com>
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <dm.h>
#include <errno.h>
#include <fdtdec.h>
#include <malloc.h>
#include <asm/io.h>
#include <asm/gpio.h>
#include <dm/device-internal.h>

DECLARE_GLOBAL_DATA_PTR;

#define SUNXI_GPIOS_PER_BANK	SUNXI_GPIO_A_NR

struct sunxi_gpio_platdata {
	struct sunxi_gpio *regs;
	const char *bank_name;	/* Name of bank, e.g. "B" */
	int gpio_count;
};

#ifndef CONFIG_DM_GPIO
static int sunxi_gpio_output(u32 pin, u32 val)
{
	u32 dat;
	u32 bank = GPIO_BANK(pin);
	u32 num = GPIO_NUM(pin);
	struct sunxi_gpio *pio = BANK_TO_GPIO(bank);

	dat = readl(&pio->dat);
	if (val)
		dat |= 0x1 << num;
	else
		dat &= ~(0x1 << num);

	writel(dat, &pio->dat);

	return 0;
}

static int sunxi_gpio_input(u32 pin)
{
	u32 dat;
	u32 bank = GPIO_BANK(pin);
	u32 num = GPIO_NUM(pin);
	struct sunxi_gpio *pio = BANK_TO_GPIO(bank);

	dat = readl(&pio->dat);
	dat >>= num;

	return dat & 0x1;
}

int gpio_request(unsigned gpio, const char *label)
{
	return 0;
}

int gpio_free(unsigned gpio)
{
	return 0;
}

int gpio_direction_input(unsigned gpio)
{
	sunxi_gpio_set_cfgpin(gpio, SUNXI_GPIO_INPUT);

	return sunxi_gpio_input(gpio);
}

int gpio_direction_output(unsigned gpio, int value)
{
	sunxi_gpio_set_cfgpin(gpio, SUNXI_GPIO_OUTPUT);

	return sunxi_gpio_output(gpio, value);
}

int gpio_get_value(unsigned gpio)
{
	return sunxi_gpio_input(gpio);
}

int gpio_set_value(unsigned gpio, int value)
{
	return sunxi_gpio_output(gpio, value);
}

int sunxi_name_to_gpio(const char *name)
{
	int group = 0;
	int groupsize = 9 * 32;
	long pin;
	char *eptr;
	if (*name == 'P' || *name == 'p')
		name++;
	if (*name >= 'A') {
		group = *name - (*name > 'a' ? 'a' : 'A');
		groupsize = 32;
		name++;
	}

	pin = simple_strtol(name, &eptr, 10);
	if (!*name || *eptr)
		return -1;
	if (pin < 0 || pin > groupsize || group >= 9)
		return -1;
	return group * 32 + pin;
}
#endif

#ifdef CONFIG_DM_GPIO
static int sunxi_gpio_direction_input(struct udevice *dev, unsigned offset)
{
	struct sunxi_gpio_platdata *plat = dev_get_platdata(dev);

	sunxi_gpio_set_cfgbank(plat->regs, offset, SUNXI_GPIO_INPUT);

	return 0;
}

static int sunxi_gpio_direction_output(struct udevice *dev, unsigned offset,
				       int value)
{
	struct sunxi_gpio_platdata *plat = dev_get_platdata(dev);
	u32 num = GPIO_NUM(offset);

	sunxi_gpio_set_cfgbank(plat->regs, offset, SUNXI_GPIO_OUTPUT);
	clrsetbits_le32(&plat->regs->dat, 1 << num, value ? (1 << num) : 0);

	return 0;
}

static int sunxi_gpio_get_value(struct udevice *dev, unsigned offset)
{
	struct sunxi_gpio_platdata *plat = dev_get_platdata(dev);
	u32 num = GPIO_NUM(offset);
	unsigned dat;

	dat = readl(&plat->regs->dat);
	dat >>= num;

	return dat & 0x1;
}

static int sunxi_gpio_set_value(struct udevice *dev, unsigned offset,
				int value)
{
	struct sunxi_gpio_platdata *plat = dev_get_platdata(dev);
	u32 num = GPIO_NUM(offset);

	clrsetbits_le32(&plat->regs->dat, 1 << num, value ? (1 << num) : 0);
	return 0;
}

static int sunxi_gpio_get_function(struct udevice *dev, unsigned offset)
{
	struct sunxi_gpio_platdata *plat = dev_get_platdata(dev);
	int func;

	func = sunxi_gpio_get_cfgbank(plat->regs, offset);
	if (func == SUNXI_GPIO_OUTPUT)
		return GPIOF_OUTPUT;
	else if (func == SUNXI_GPIO_INPUT)
		return GPIOF_INPUT;
	else
		return GPIOF_FUNC;
}

static const struct dm_gpio_ops gpio_sunxi_ops = {
	.direction_input	= sunxi_gpio_direction_input,
	.direction_output	= sunxi_gpio_direction_output,
	.get_value		= sunxi_gpio_get_value,
	.set_value		= sunxi_gpio_set_value,
	.get_function		= sunxi_gpio_get_function,
};

/**
 * Returns the name of a GPIO bank
 *
 * GPIO banks are named A, B, C, ...
 *
 * @bank:	Bank number (0, 1..n-1)
 * @return allocated string containing the name
 */
static char *gpio_bank_name(int bank)
{
	char *name;

	name = malloc(2);
	if (name) {
		name[0] = 'A' + bank;
		name[1] = '\0';
	}

	return name;
}

static int gpio_sunxi_probe(struct udevice *dev)
{
	struct sunxi_gpio_platdata *plat = dev_get_platdata(dev);
	struct gpio_dev_priv *uc_priv = dev->uclass_priv;

	/* Tell the uclass how many GPIOs we have */
	if (plat) {
		uc_priv->gpio_count = plat->gpio_count;
		uc_priv->bank_name = plat->bank_name;
	}

	return 0;
}
/**
 * We have a top-level GPIO device with no actual GPIOs. It has a child
 * device for each Sunxi bank.
 */
static int gpio_sunxi_bind(struct udevice *parent)
{
	struct sunxi_gpio_platdata *plat = parent->platdata;
	struct sunxi_gpio_reg *ctlr;
	int bank;
	int ret;

	/* If this is a child device, there is nothing to do here */
	if (plat)
		return 0;

	ctlr = (struct sunxi_gpio_reg *)fdtdec_get_addr(gd->fdt_blob,
						   parent->of_offset, "reg");
	for (bank = 0; bank < SUNXI_GPIO_BANKS; bank++) {
		struct sunxi_gpio_platdata *plat;
		struct udevice *dev;

		plat = calloc(1, sizeof(*plat));
		if (!plat)
			return -ENOMEM;
		plat->regs = &ctlr->gpio_bank[bank];
		plat->bank_name = gpio_bank_name(bank);
		plat->gpio_count = SUNXI_GPIOS_PER_BANK;

		ret = device_bind(parent, parent->driver,
					plat->bank_name, plat, -1, &dev);
		if (ret)
			return ret;
		dev->of_offset = parent->of_offset;
	}

	return 0;
}

static const struct udevice_id sunxi_gpio_ids[] = {
	{ .compatible = "allwinner,sun7i-a20-pinctrl" },
	{ }
};

U_BOOT_DRIVER(gpio_sunxi) = {
	.name	= "gpio_sunxi",
	.id	= UCLASS_GPIO,
	.ops	= &gpio_sunxi_ops,
	.of_match = sunxi_gpio_ids,
	.bind	= gpio_sunxi_bind,
	.probe	= gpio_sunxi_probe,
};
#endif