/*
 * Copyright (C) 2021 Denis 'GNUtoo' Carikli <GNUtoo@cyberdimension.org>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

#include <errno.h>
#include <stdio.h>
#include <stdint.h>
#include <string.h>

#include <sys/mman.h>

#include "exynos4412_gpios.h"
#include "exynos4412_gpios_data.h"

void *mmap_gpio_hardware_blocks(int debug, char *devmem, int fd,
				size_t page_size)
{
	/* TODO: also map GPIO_right
	 * GPIO_right: base_addr: 0x11000000 len: 0x400000
	 * GPIO_left: base_addr:  0x11400000 len: 0x400000
	 */
	uint32_t base_addr = 0x11000000;
	size_t len = 0x800000;

	void *map_base_addr;
	uint32_t *virt_addr;

	int rc;

	map_base_addr = mmap(0, len, PROT_READ|PROT_WRITE, MAP_SHARED, fd,
			     base_addr & ~(page_size -1));
	if (map_base_addr == MAP_FAILED) {
		rc = errno;
		printf("mmap on %s failed with error %d: %s\n",
		       devmem, rc, strerror(rc));
		errno = rc;
		return NULL;
	}

	virt_addr = map_base_addr + (base_addr & 4095);

	if (debug) {
		printf("%s: mapped address 0x%x @ %p\n", __func__, 0,
		       map_base_addr);
		printf("%s: mapped 0x%x bytes of address 0x%x @ %p\n", __func__,
		       len, base_addr, virt_addr);
	}

	return virt_addr;
}

int dump_gpio_infos(int debug, char *devmem, int fd, size_t page_size,
		    void *gpio_hardware_blocks_addr, char *bank,
		    uint32_t gpio_offset)
{
	uint32_t *addr;
	int rc;
	int i = 0;
	off_t offset = 0;

	char* gpio_registers[] = { "con", "dat", "pud", "drv" };

	offset = get_gpio_register_offset(debug, bank, "con");
	if (offset == -1) {
		rc = errno;
		printf("%s: get_gpio_register_offset failed with error %d: %s\n",
		       __func__, rc, strerror(rc));
		return -1;
	}


	addr = gpio_hardware_blocks_addr + offset;

	if (debug) {
		printf("%s: Mapped at %p\n", __func__, addr);
		print_gpio_banks_data();
	}

	printf("%s: %s[%d]: {\n",  __func__, bank, gpio_offset);
	for (i=0; i< sizeof(gpio_registers) / sizeof (char*); i++) {

		rc = decode_gpio_data(debug, bank, gpio_offset,
				      gpio_registers[i], addr);
		if (rc == -1) {
			rc = errno;
			printf("%s:"
			       " decode_gpio_data(debug=%d,"
			       " bank=%s,"
			       " gpio_offset=%d,"
			       " gpio_register_name=%s,"
			       " addr=%p);"
			       " failed with with error %d: %s\n",
			       __func__,
			       debug,
			       bank,
			       gpio_offset,
			       gpio_registers[i],
			       addr,
			       rc, strerror(rc));
			return -1;
		}

		printf("  %s\n", gpio_data_str(gpio_registers[i], rc));
	}
	printf("}\n");

	return 0;
}

int gpio_get_direction(char *devmem, int fd, size_t page_size, char *bank,
		  uint32_t gpio_offset)
{
	int debug = 0;

	uint32_t *addr;
	int rc;
	off_t offset = 0;

	offset = get_gpio_register_offset(debug, bank, "con");
	if (offset == -1) {
		rc = errno;
		printf("%s: get_gpio_register_offset failed with error %d: %s\n",
		       __func__, rc, strerror(rc));
		return -1;
	}

	addr = mmap_gpio_hardware_blocks(debug, devmem, fd, page_size) + offset;
	if (addr == NULL) {
		/* mmap_gpio_bank already prints an error */
		return -1;
	}

	if (debug) {
		printf("%s: Mapped at %p\n", __func__, addr);
		print_gpio_banks_data();
	}

	rc = decode_gpio_data(debug, bank, gpio_offset,
				      "con", addr);
	if (rc == -1) {
		rc = errno;
		printf("%s:"
		       " decode_gpio_data(debug=%d,"
		       " bank=%s,"
		       " gpio_offset=%d,"
		       " gpio_register_name=%s,"
		       " addr=%p);"
		       " failed with with error %d: %s\n",
		       __func__,
		       debug,
		       bank,
		       gpio_offset,
		       "con",
		       addr,
		       rc, strerror(rc));
		return -1;
	}

	return rc;
}

int gpio_get_output_value(char *devmem, int fd, size_t page_size, char *bank,
			  uint32_t gpio_offset)
{
	int debug = 0;

	uint32_t *addr;
	int rc;
	off_t offset = 0;

	offset = get_gpio_register_offset(debug, bank, "dat");
	if (offset == -1) {
		rc = errno;
		printf("%s: get_gpio_register_offset failed with error %d: %s\n",
		       __func__, rc, strerror(rc));
		return -1;
	}

	if (debug){
		printf("%s: offset for %s: 0x%lx\n\n",
		       __func__, bank, offset);
	}

	addr = mmap_gpio_hardware_blocks(debug, devmem, fd, page_size) + offset;
	if (addr == NULL) {
		/* mmap_gpio_bank already prints an error */
		return -1;
	}

	if (debug) {
		printf("%s: Mapped at %p\n", __func__, addr);
		print_gpio_banks_data();
	}

	rc = decode_gpio_data(debug, bank, gpio_offset,
				      "dat", addr);
	if (rc == -1) {
		rc = errno;
		printf("%s:"
		       " decode_gpio_data(debug=%d,"
		       " bank=%s,"
		       " gpio_offset=%d,"
		       " gpio_register_name=%s,"
		       " addr=%p);"
		       " failed with with error %d: %s\n",
		       __func__,
		       debug,
		       bank,
		       gpio_offset,
		       "dat",
		       addr,
		       rc, strerror(rc));
		return -1;
	}

	return rc;
}