/*
 * This file is part of the flashrom project.
 *
 * SPDX-License-Identifier: GPL-2.0-only
 * SPDX-FileCopyrightText: 2009,2010 Carl-Daniel Hailfinger
 */

/* Driver for various LPT adapters.
 *
 * This driver uses non-portable direct I/O port accesses which won't work on
 * any non-x86 platform, and even on x86 there is a high chance there will be
 * collisions with any loaded parallel port drivers.
 * The big advantage of direct port I/O is OS independence and speed because
 * most OS parport drivers will perform many unnecessary accesses although
 * this driver just treats the parallel port as a GPIO set.
 */

#include <stdlib.h>
#include <strings.h>
#include <string.h>
#include "flash.h"
#include "programmer.h"
#include "hwaccess_x86_io.h"

/* We have two sets of pins, out and in. The numbers for both sets are
 * independent and are bitshift values, not real pin numbers.
 * Default settings are for the RayeR hardware.
 */

struct rayer_programmer {
	const char *type;
	const enum test_state status;
	const char *description;
	const void *dev_data;
};

struct rayer_pinout {
	uint8_t cs_bit;
	uint8_t sck_bit;
	uint8_t mosi_bit;
	uint8_t miso_bit;
	void (*preinit)(void *);
	int (*shutdown)(void *);
};

struct rayer_spi_data {
	uint16_t lpt_iobase;
	/* Cached value of last byte sent. */
	uint8_t lpt_outbyte;

	const struct rayer_pinout *pinout;
};

static const struct rayer_pinout rayer_spipgm = {
	.cs_bit = 5,
	.sck_bit = 6,
	.mosi_bit = 7,
	.miso_bit = 6,
};

static void dlc5_preinit(void *spi_data)
{
	struct rayer_spi_data *data = spi_data;

	msg_pdbg("dlc5_preinit\n");
	/* Assert pin 6 to receive MISO. */
	data->lpt_outbyte |= (1<<4);
	OUTB(data->lpt_outbyte, data->lpt_iobase);
}

static int dlc5_shutdown(void *spi_data)
{
	struct rayer_spi_data *data = spi_data;

	msg_pdbg("dlc5_shutdown\n");
	/* De-assert pin 6 to force MISO low. */
	data->lpt_outbyte &= ~(1<<4);
	OUTB(data->lpt_outbyte, data->lpt_iobase);

	free(data);
	return 0;
}

static const struct rayer_pinout xilinx_dlc5 = {
	.cs_bit = 2,
	.sck_bit = 1,
	.mosi_bit = 0,
	.miso_bit = 4,
	.preinit =  dlc5_preinit,
	.shutdown = dlc5_shutdown,
};

static void byteblaster_preinit(void *spi_data)
{
	struct rayer_spi_data *data = spi_data;

	msg_pdbg("byteblaster_preinit\n");
	/* Assert #EN signal. */
	OUTB(2, data->lpt_iobase + 2 );
}

static int byteblaster_shutdown(void *spi_data)
{
	struct rayer_spi_data *data = spi_data;

	msg_pdbg("byteblaster_shutdown\n");
	/* De-Assert #EN signal. */
	OUTB(0, data->lpt_iobase + 2 );

	free(data);
	return 0;
}

static const struct rayer_pinout altera_byteblastermv = {
	.cs_bit = 1,
	.sck_bit = 0,
	.mosi_bit = 6,
	.miso_bit = 7,
	.preinit =  byteblaster_preinit,
	.shutdown = byteblaster_shutdown,
};

static void stk200_preinit(void *spi_data)
{
	struct rayer_spi_data *data = spi_data;

	msg_pdbg("stk200_init\n");
	/* Assert #EN signals, set LED signal. */
	data->lpt_outbyte = (1 << 6) ;
	OUTB(data->lpt_outbyte, data->lpt_iobase);
}

static int stk200_shutdown(void *spi_data)
{
	struct rayer_spi_data *data = spi_data;

	msg_pdbg("stk200_shutdown\n");
	/* Assert #EN signals, clear LED signal. */
	data->lpt_outbyte = (1 << 2) | (1 << 3);
	OUTB(data->lpt_outbyte, data->lpt_iobase);

	free(data);
	return 0;
}

static const struct rayer_pinout atmel_stk200 = {
	.cs_bit = 7,
	.sck_bit = 4,
	.mosi_bit = 5,
	.miso_bit = 6,
	.preinit =  stk200_preinit,
	.shutdown = stk200_shutdown,
};

static const struct rayer_pinout wiggler_lpt = {
	.cs_bit = 1,
	.sck_bit = 2,
	.mosi_bit = 3,
	.miso_bit = 7,
};

static const struct rayer_pinout spi_tt = {
	.cs_bit = 2,
	.sck_bit = 0,
	.mosi_bit = 4,
	.miso_bit = 7,
};

static void rayer_bitbang_set_cs(int val, void *spi_data)
{
	struct rayer_spi_data *data = spi_data;

	data->lpt_outbyte &= ~(1 << data->pinout->cs_bit);
	data->lpt_outbyte |= (val << data->pinout->cs_bit);
	OUTB(data->lpt_outbyte, data->lpt_iobase);
}

static void rayer_bitbang_set_sck(int val, void *spi_data)
{
	struct rayer_spi_data *data = spi_data;

	data->lpt_outbyte &= ~(1 << data->pinout->sck_bit);
	data->lpt_outbyte |= (val << data->pinout->sck_bit);
	OUTB(data->lpt_outbyte, data->lpt_iobase);
}

static void rayer_bitbang_set_mosi(int val, void *spi_data)
{
	struct rayer_spi_data *data = spi_data;

	data->lpt_outbyte &= ~(1 << data->pinout->mosi_bit);
	data->lpt_outbyte |= (val << data->pinout->mosi_bit);
	OUTB(data->lpt_outbyte, data->lpt_iobase);
}

static int rayer_bitbang_get_miso(void *spi_data)
{
	struct rayer_spi_data *data = spi_data;
	uint8_t tmp;

	tmp = INB(data->lpt_iobase + 1) ^ 0x80; // bit.7 inverted
	tmp = (tmp >> data->pinout->miso_bit) & 0x1;
	return tmp;
}

static int rayer_shutdown(void *spi_data)
{
	free(spi_data);
	return 0;
}

static const struct bitbang_spi_master bitbang_spi_master_rayer = {
	.set_cs		= rayer_bitbang_set_cs,
	.set_sck	= rayer_bitbang_set_sck,
	.set_mosi	= rayer_bitbang_set_mosi,
	.get_miso	= rayer_bitbang_get_miso,
	.half_period	= 0,
};

static const struct rayer_programmer *find_progtype(const char *prog_type)
{
	static const struct rayer_programmer rayer_spi_types[] = {
		{"rayer",		NT,	"RayeR SPIPGM",					&rayer_spipgm},
		{"xilinx",		NT,	"Xilinx Parallel Cable III (DLC 5)",		&xilinx_dlc5},
		{"byteblastermv",	OK,	"Altera ByteBlasterMV",				&altera_byteblastermv},
		{"stk200",		NT,	"Atmel STK200/300 adapter",			&atmel_stk200},
		{"wiggler",		OK,	"Wiggler LPT",					&wiggler_lpt},
		{"spi_tt",		NT,	"SPI Tiny Tools (SPI_TT LPT)",			&spi_tt},
		{0},
	};
	if (!prog_type)
		return &rayer_spi_types[0];

	const struct rayer_programmer *prog = rayer_spi_types;
	for (; prog->type != NULL; prog++) {
		if (strcasecmp(prog_type, prog->type) == 0) {
			break;
		}
	}

	if (!prog->type) {
		msg_perr("Error: Invalid device type specified.\n");
		return NULL;
	}

	return prog;
}

static int get_params(const struct programmer_cfg *cfg, uint16_t *lpt_iobase,
		      const struct rayer_programmer **prog)
{
	/* Pick a default value for the I/O base. */
	*lpt_iobase = 0x378;
	/* no programmer type specified. */
	*prog = NULL;

	/* Non-default port requested? */
	char *arg = extract_programmer_param_str(cfg, "iobase");
	if (arg) {
		char *endptr = NULL;
		unsigned long tmp = strtoul(arg, &endptr, 0);
		/* Port 0, port >0x10000, unaligned ports and garbage strings
		 * are rejected.
		 */
		if (!tmp || (tmp >= 0x10000) || (tmp & 0x3) ||
		    (*endptr != '\0')) {
			/* Using ports below 0x100 is a really bad idea, and
			 * should only be done if no port between 0x100 and
			 * 0xfffc works due to routing issues.
			 */
			msg_perr("Error: iobase= specified, but the I/O base "
				 "given was invalid.\nIt must be a multiple of "
				 "0x4 and lie between 0x100 and 0xfffc.\n");
			free(arg);
			return -1;
		} else {
			*lpt_iobase = (uint16_t)tmp;
			msg_pinfo("Non-default I/O base requested. This will "
				  "not change the hardware settings.\n");
		}
		free(arg);
	}

	arg = extract_programmer_param_str(cfg, "type");
	*prog = find_progtype(arg);
	free(arg);

	return *prog ? 0 : -1;
}

static int rayer_spi_init(const struct programmer_cfg *cfg)
{
	const struct rayer_programmer *prog;
	struct rayer_pinout *pinout = NULL;
	uint16_t lpt_iobase;

	if (get_params(cfg, &lpt_iobase, &prog) < 0)
		return 1;

	msg_pdbg("Using address 0x%x as I/O base for parallel port access.\n",
		 lpt_iobase);

	msg_pinfo("Using %s pinout.\n", prog->description);
	pinout = (struct rayer_pinout *)prog->dev_data;

	if (rget_io_perms())
		return 1;

	struct rayer_spi_data *data = calloc(1, sizeof(*data));
	if (!data) {
		msg_perr("Unable to allocate space for SPI master data\n");
		return 1;
	}
	data->pinout = pinout;
	data->lpt_iobase = lpt_iobase;
	/* Get the initial value before writing to any line. */
	data->lpt_outbyte = INB(lpt_iobase);

	if (pinout->shutdown)
		register_shutdown(pinout->shutdown, data);
	else
		register_shutdown(rayer_shutdown, data);

	if (pinout->preinit)
		pinout->preinit(data);

	if (register_spi_bitbang_master(&bitbang_spi_master_rayer, data))
		return 1;

	return 0;
}

const struct programmer_entry programmer_rayer_spi = {
	.name			= "rayer_spi",
	.type			= OTHER,
				/* FIXME */
	.devs.note		= "RayeR parallel port programmer\n",
	.init			= rayer_spi_init,
};
