// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Copyright (c) 1998-2001 Vojtech Pavlik
 *
 *   Based on the work of:
 *	Trystan Larey-Williams
 */

/*
 * ThrustMaster DirectConnect (BSP) joystick family driver for Linux
 */

#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/gameport.h>
#include <linux/input.h>
#include <linux/jiffies.h>

#define DRIVER_DESC	"ThrustMaster DirectConnect joystick driver"

MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");

#define TMDC_MAX_START		600	/* 600 us */
#define TMDC_MAX_STROBE		60	/* 60 us */
#define TMDC_MAX_LENGTH		13

#define TMDC_MODE_M3DI		1
#define TMDC_MODE_3DRP		3
#define TMDC_MODE_AT		4
#define TMDC_MODE_FM		8
#define TMDC_MODE_FGP		163

#define TMDC_BYTE_ID		10
#define TMDC_BYTE_REV		11
#define TMDC_BYTE_DEF		12

#define TMDC_ABS		7
#define TMDC_ABS_HAT		4
#define TMDC_BTN		16

static const unsigned char tmdc_byte_a[16] = { 0, 1, 3, 4, 6, 7 };
static const unsigned char tmdc_byte_d[16] = { 2, 5, 8, 9 };

static const signed char tmdc_abs[TMDC_ABS] =
	{ ABS_X, ABS_Y, ABS_RUDDER, ABS_THROTTLE, ABS_RX, ABS_RY, ABS_RZ };
static const signed char tmdc_abs_hat[TMDC_ABS_HAT] =
	{ ABS_HAT0X, ABS_HAT0Y, ABS_HAT1X, ABS_HAT1Y };
static const signed char tmdc_abs_at[TMDC_ABS] =
	{ ABS_X, ABS_Y, ABS_RUDDER, -1, ABS_THROTTLE };
static const signed char tmdc_abs_fm[TMDC_ABS] =
	{ ABS_RX, ABS_RY, ABS_X, ABS_Y };

static const short tmdc_btn_pad[TMDC_BTN] =
	{ BTN_A, BTN_B, BTN_C, BTN_X, BTN_Y, BTN_Z, BTN_START, BTN_SELECT, BTN_TL, BTN_TR };
static const short tmdc_btn_joy[TMDC_BTN] =
	{ BTN_TRIGGER, BTN_THUMB, BTN_TOP, BTN_TOP2, BTN_BASE, BTN_BASE2, BTN_THUMB2, BTN_PINKIE,
	  BTN_BASE3, BTN_BASE4, BTN_A, BTN_B, BTN_C, BTN_X, BTN_Y, BTN_Z };
static const short tmdc_btn_fm[TMDC_BTN] =
        { BTN_TRIGGER, BTN_C, BTN_B, BTN_A, BTN_THUMB, BTN_X, BTN_Y, BTN_Z, BTN_TOP, BTN_TOP2 };
static const short tmdc_btn_at[TMDC_BTN] =
        { BTN_TRIGGER, BTN_THUMB2, BTN_PINKIE, BTN_THUMB, BTN_BASE6, BTN_BASE5, BTN_BASE4,
          BTN_BASE3, BTN_BASE2, BTN_BASE };

static const struct {
        int x;
        int y;
} tmdc_hat_to_axis[] = {{ 0, 0}, { 1, 0}, { 0,-1}, {-1, 0}, { 0, 1}};

static const struct tmdc_model {
	unsigned char id;
	const char *name;
	char abs;
	char hats;
	char btnc[4];
	char btno[4];
	const signed char *axes;
	const short *buttons;
} tmdc_models[] = {
	{   1, "ThrustMaster Millennium 3D Inceptor",	  6, 2, { 4, 2 }, { 4, 6 }, tmdc_abs, tmdc_btn_joy },
	{   3, "ThrustMaster Rage 3D Gamepad",		  2, 0, { 8, 2 }, { 0, 0 }, tmdc_abs, tmdc_btn_pad },
	{   4, "ThrustMaster Attack Throttle",		  5, 2, { 4, 6 }, { 4, 2 }, tmdc_abs_at, tmdc_btn_at },
	{   8, "ThrustMaster FragMaster",		  4, 0, { 8, 2 }, { 0, 0 }, tmdc_abs_fm, tmdc_btn_fm },
	{ 163, "Thrustmaster Fusion GamePad",		  2, 0, { 8, 2 }, { 0, 0 }, tmdc_abs, tmdc_btn_pad },
	{   0, "Unknown %d-axis, %d-button TM device %d", 0, 0, { 0, 0 }, { 0, 0 }, tmdc_abs, tmdc_btn_joy }
};


struct tmdc_port {
	struct input_dev *dev;
	char name[64];
	char phys[32];
	int mode;
	const signed char *abs;
	const short *btn;
	unsigned char absc;
	unsigned char btnc[4];
	unsigned char btno[4];
};

struct tmdc {
	struct gameport *gameport;
	struct tmdc_port *port[2];
#if 0
	struct input_dev *dev[2];
	char name[2][64];
	char phys[2][32];
	int mode[2];
	signed char *abs[2];
	short *btn[2];
	unsigned char absc[2];
	unsigned char btnc[2][4];
	unsigned char btno[2][4];
#endif
	int reads;
	int bads;
	unsigned char exists;
};

/*
 * tmdc_read_packet() reads a ThrustMaster packet.
 */

static int tmdc_read_packet(struct gameport *gameport, unsigned char data[2][TMDC_MAX_LENGTH])
{
	unsigned char u, v, w, x;
	unsigned long flags;
	int i[2], j[2], t[2], p, k;

	p = gameport_time(gameport, TMDC_MAX_STROBE);

	for (k = 0; k < 2; k++) {
		t[k] = gameport_time(gameport, TMDC_MAX_START);
		i[k] = j[k] = 0;
	}

	local_irq_save(flags);
	gameport_trigger(gameport);

	w = gameport_read(gameport) >> 4;

	do {
		x = w;
		w = gameport_read(gameport) >> 4;

		for (k = 0, v = w, u = x; k < 2; k++, v >>= 2, u >>= 2) {
			if (~v & u & 2) {
				if (t[k] <= 0 || i[k] >= TMDC_MAX_LENGTH) continue;
				t[k] = p;
				if (j[k] == 0) {				 /* Start bit */
					if (~v & 1) t[k] = 0;
					data[k][i[k]] = 0; j[k]++; continue;
				}
				if (j[k] == 9) {				/* Stop bit */
					if (v & 1) t[k] = 0;
					j[k] = 0; i[k]++; continue;
				}
				data[k][i[k]] |= (~v & 1) << (j[k]++ - 1);	/* Data bit */
			}
			t[k]--;
		}
	} while (t[0] > 0 || t[1] > 0);

	local_irq_restore(flags);

	return (i[0] == TMDC_MAX_LENGTH) | ((i[1] == TMDC_MAX_LENGTH) << 1);
}

static int tmdc_parse_packet(struct tmdc_port *port, unsigned char *data)
{
	int i, k, l;

	if (data[TMDC_BYTE_ID] != port->mode)
		return -1;

	for (i = 0; i < port->absc; i++) {
		if (port->abs[i] < 0)
			return 0;

		input_report_abs(port->dev, port->abs[i], data[tmdc_byte_a[i]]);
	}

	switch (port->mode) {

		case TMDC_MODE_M3DI:

			i = tmdc_byte_d[0];
			input_report_abs(port->dev, ABS_HAT0X, ((data[i] >> 3) & 1) - ((data[i] >> 1) & 1));
			input_report_abs(port->dev, ABS_HAT0Y, ((data[i] >> 2) & 1) - ( data[i]       & 1));
			break;

		case TMDC_MODE_AT:

			i = tmdc_byte_a[3];
			input_report_abs(port->dev, ABS_HAT0X, tmdc_hat_to_axis[(data[i] - 141) / 25].x);
			input_report_abs(port->dev, ABS_HAT0Y, tmdc_hat_to_axis[(data[i] - 141) / 25].y);
			break;

	}

	for (k = l = 0; k < 4; k++) {
		for (i = 0; i < port->btnc[k]; i++)
			input_report_key(port->dev, port->btn[i + l],
				((data[tmdc_byte_d[k]] >> (i + port->btno[k])) & 1));
		l += port->btnc[k];
	}

	input_sync(port->dev);

	return 0;
}

/*
 * tmdc_poll() reads and analyzes ThrustMaster joystick data.
 */

static void tmdc_poll(struct gameport *gameport)
{
	unsigned char data[2][TMDC_MAX_LENGTH];
	struct tmdc *tmdc = gameport_get_drvdata(gameport);
	unsigned char r, bad = 0;
	int i;

	tmdc->reads++;

	if ((r = tmdc_read_packet(tmdc->gameport, data)) != tmdc->exists)
		bad = 1;
	else {
		for (i = 0; i < 2; i++) {
			if (r & (1 << i) & tmdc->exists) {

				if (tmdc_parse_packet(tmdc->port[i], data[i]))
					bad = 1;
			}
		}
	}

	tmdc->bads += bad;
}

static int tmdc_open(struct input_dev *dev)
{
	struct tmdc *tmdc = input_get_drvdata(dev);

	gameport_start_polling(tmdc->gameport);
	return 0;
}

static void tmdc_close(struct input_dev *dev)
{
	struct tmdc *tmdc = input_get_drvdata(dev);

	gameport_stop_polling(tmdc->gameport);
}

static int tmdc_setup_port(struct tmdc *tmdc, int idx, unsigned char *data)
{
	const struct tmdc_model *model;
	struct tmdc_port *port;
	struct input_dev *input_dev;
	int i, j, b = 0;
	int err;

	tmdc->port[idx] = port = kzalloc(sizeof (struct tmdc_port), GFP_KERNEL);
	input_dev = input_allocate_device();
	if (!port || !input_dev) {
		err = -ENOMEM;
		goto fail;
	}

	port->mode = data[TMDC_BYTE_ID];

	for (model = tmdc_models; model->id && model->id != port->mode; model++)
		/* empty */;

	port->abs = model->axes;
	port->btn = model->buttons;

	if (!model->id) {
		port->absc = data[TMDC_BYTE_DEF] >> 4;
		for (i = 0; i < 4; i++)
			port->btnc[i] = i < (data[TMDC_BYTE_DEF] & 0xf) ? 8 : 0;
	} else {
		port->absc = model->abs;
		for (i = 0; i < 4; i++)
			port->btnc[i] = model->btnc[i];
	}

	for (i = 0; i < 4; i++)
		port->btno[i] = model->btno[i];

	snprintf(port->name, sizeof(port->name), model->name,
		 port->absc, (data[TMDC_BYTE_DEF] & 0xf) << 3, port->mode);
	snprintf(port->phys, sizeof(port->phys), "%s/input%d", tmdc->gameport->phys, i);

	port->dev = input_dev;

	input_dev->name = port->name;
	input_dev->phys = port->phys;
	input_dev->id.bustype = BUS_GAMEPORT;
	input_dev->id.vendor = GAMEPORT_ID_VENDOR_THRUSTMASTER;
	input_dev->id.product = model->id;
	input_dev->id.version = 0x0100;
	input_dev->dev.parent = &tmdc->gameport->dev;

	input_set_drvdata(input_dev, tmdc);

	input_dev->open = tmdc_open;
	input_dev->close = tmdc_close;

	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);

	for (i = 0; i < port->absc && i < TMDC_ABS; i++)
		if (port->abs[i] >= 0)
			input_set_abs_params(input_dev, port->abs[i], 8, 248, 2, 4);

	for (i = 0; i < model->hats && i < TMDC_ABS_HAT; i++)
		input_set_abs_params(input_dev, tmdc_abs_hat[i], -1, 1, 0, 0);

	for (i = 0; i < 4; i++) {
		for (j = 0; j < port->btnc[i] && j < TMDC_BTN; j++)
			set_bit(port->btn[j + b], input_dev->keybit);
		b += port->btnc[i];
	}

	err = input_register_device(port->dev);
	if (err)
		goto fail;

	return 0;

 fail:	input_free_device(input_dev);
	kfree(port);
	return err;
}

/*
 * tmdc_probe() probes for ThrustMaster type joysticks.
 */

static int tmdc_connect(struct gameport *gameport, struct gameport_driver *drv)
{
	unsigned char data[2][TMDC_MAX_LENGTH];
	struct tmdc *tmdc;
	int i;
	int err;

	if (!(tmdc = kzalloc(sizeof(struct tmdc), GFP_KERNEL)))
		return -ENOMEM;

	tmdc->gameport = gameport;

	gameport_set_drvdata(gameport, tmdc);

	err = gameport_open(gameport, drv, GAMEPORT_MODE_RAW);
	if (err)
		goto fail1;

	if (!(tmdc->exists = tmdc_read_packet(gameport, data))) {
		err = -ENODEV;
		goto fail2;
	}

	gameport_set_poll_handler(gameport, tmdc_poll);
	gameport_set_poll_interval(gameport, 20);

	for (i = 0; i < 2; i++) {
		if (tmdc->exists & (1 << i)) {

			err = tmdc_setup_port(tmdc, i, data[i]);
			if (err)
				goto fail3;
		}
	}

	return 0;

 fail3: while (--i >= 0) {
		if (tmdc->port[i]) {
			input_unregister_device(tmdc->port[i]->dev);
			kfree(tmdc->port[i]);
		}
	}
 fail2:	gameport_close(gameport);
 fail1:	gameport_set_drvdata(gameport, NULL);
	kfree(tmdc);
	return err;
}

static void tmdc_disconnect(struct gameport *gameport)
{
	struct tmdc *tmdc = gameport_get_drvdata(gameport);
	int i;

	for (i = 0; i < 2; i++) {
		if (tmdc->port[i]) {
			input_unregister_device(tmdc->port[i]->dev);
			kfree(tmdc->port[i]);
		}
	}
	gameport_close(gameport);
	gameport_set_drvdata(gameport, NULL);
	kfree(tmdc);
}

static struct gameport_driver tmdc_drv = {
	.driver		= {
		.name	= "tmdc",
		.owner	= THIS_MODULE,
	},
	.description	= DRIVER_DESC,
	.connect	= tmdc_connect,
	.disconnect	= tmdc_disconnect,
};

module_gameport_driver(tmdc_drv);