linux-arkmicro/u-boot/drivers/gpio/kona_gpio.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright 2013 Broadcom Corporation.
 */

#include <common.h>
#include <asm/io.h>
#include <asm/arch/sysmap.h>

#define GPIO_BASE				(void *)GPIO2_BASE_ADDR

#define GPIO_PASSWD				0x00a5a501
#define GPIO_PER_BANK				32
#define GPIO_MAX_BANK_NUM			8

#define GPIO_BANK(gpio)				((gpio) >> 5)
#define GPIO_BITMASK(gpio)	\
	(1UL << ((gpio) & (GPIO_PER_BANK - 1)))

#define GPIO_OUT_STATUS(bank)			(0x00000000 + ((bank) << 2))
#define GPIO_IN_STATUS(bank)			(0x00000020 + ((bank) << 2))
#define GPIO_OUT_SET(bank)			(0x00000040 + ((bank) << 2))
#define GPIO_OUT_CLEAR(bank)			(0x00000060 + ((bank) << 2))
#define GPIO_INT_STATUS(bank)			(0x00000080 + ((bank) << 2))
#define GPIO_INT_MASK(bank)			(0x000000a0 + ((bank) << 2))
#define GPIO_INT_MSKCLR(bank)			(0x000000c0 + ((bank) << 2))
#define GPIO_CONTROL(bank)			(0x00000100 + ((bank) << 2))
#define GPIO_PWD_STATUS(bank)			(0x00000500 + ((bank) << 2))

#define GPIO_GPPWR_OFFSET			0x00000520

#define GPIO_GPCTR0_DBR_SHIFT			5
#define GPIO_GPCTR0_DBR_MASK			0x000001e0

#define GPIO_GPCTR0_ITR_SHIFT			3
#define GPIO_GPCTR0_ITR_MASK			0x00000018
#define GPIO_GPCTR0_ITR_CMD_RISING_EDGE		0x00000001
#define GPIO_GPCTR0_ITR_CMD_FALLING_EDGE	0x00000002
#define GPIO_GPCTR0_ITR_CMD_BOTH_EDGE		0x00000003

#define GPIO_GPCTR0_IOTR_MASK			0x00000001
#define GPIO_GPCTR0_IOTR_CMD_0UTPUT		0x00000000
#define GPIO_GPCTR0_IOTR_CMD_INPUT		0x00000001

int gpio_request(unsigned gpio, const char *label)
{
	unsigned int value, off;

	writel(GPIO_PASSWD, GPIO_BASE + GPIO_GPPWR_OFFSET);
	off = GPIO_PWD_STATUS(GPIO_BANK(gpio));
	value = readl(GPIO_BASE + off) & ~GPIO_BITMASK(gpio);
	writel(value, GPIO_BASE + off);

	return 0;
}

int gpio_free(unsigned gpio)
{
	unsigned int value, off;

	writel(GPIO_PASSWD, GPIO_BASE + GPIO_GPPWR_OFFSET);
	off = GPIO_PWD_STATUS(GPIO_BANK(gpio));
	value = readl(GPIO_BASE + off) | GPIO_BITMASK(gpio);
	writel(value, GPIO_BASE + off);

	return 0;
}

int gpio_direction_input(unsigned gpio)
{
	u32 val;

	val = readl(GPIO_BASE + GPIO_CONTROL(gpio));
	val &= ~GPIO_GPCTR0_IOTR_MASK;
	val |= GPIO_GPCTR0_IOTR_CMD_INPUT;
	writel(val, GPIO_BASE + GPIO_CONTROL(gpio));

	return 0;
}

int gpio_direction_output(unsigned gpio, int value)
{
	int bank_id = GPIO_BANK(gpio);
	int bitmask = GPIO_BITMASK(gpio);
	u32 val, off;

	val = readl(GPIO_BASE + GPIO_CONTROL(gpio));
	val &= ~GPIO_GPCTR0_IOTR_MASK;
	val |= GPIO_GPCTR0_IOTR_CMD_0UTPUT;
	writel(val, GPIO_BASE + GPIO_CONTROL(gpio));
	off = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);

	val = readl(GPIO_BASE + off);
	val |= bitmask;
	writel(val, GPIO_BASE + off);

	return 0;
}

int gpio_get_value(unsigned gpio)
{
	int bank_id = GPIO_BANK(gpio);
	int bitmask = GPIO_BITMASK(gpio);
	u32 val, off;

	/* determine the GPIO pin direction */
	val = readl(GPIO_BASE + GPIO_CONTROL(gpio));
	val &= GPIO_GPCTR0_IOTR_MASK;

	/* read the GPIO bank status */
	off = (GPIO_GPCTR0_IOTR_CMD_INPUT == val) ?
	    GPIO_IN_STATUS(bank_id) : GPIO_OUT_STATUS(bank_id);
	val = readl(GPIO_BASE + off);

	/* return the specified bit status */
	return !!(val & bitmask);
}

void gpio_set_value(unsigned gpio, int value)
{
	int bank_id = GPIO_BANK(gpio);
	int bitmask = GPIO_BITMASK(gpio);
	u32 val, off;

	/* determine the GPIO pin direction */
	val = readl(GPIO_BASE + GPIO_CONTROL(gpio));
	val &= GPIO_GPCTR0_IOTR_MASK;

	/* this function only applies to output pin */
	if (GPIO_GPCTR0_IOTR_CMD_INPUT == val) {
		printf("%s: Cannot set an input pin %d\n", __func__, gpio);
		return;
	}

	off = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);

	val = readl(GPIO_BASE + off);
	val |= bitmask;
	writel(val, GPIO_BASE + off);
}