// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Copyright (c) 1998-2001 Vojtech Pavlik
 */

/*
 * FP-Gaming Assassin 3D joystick driver for Linux
 */

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

#define DRIVER_DESC     "FP-Gaming Assassin 3D joystick driver"

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

#define A3D_MAX_START           600     /* 600 us */
#define A3D_MAX_STROBE          80      /* 80 us */
#define A3D_MAX_LENGTH          40      /* 40*3 bits */

#define A3D_MODE_A3D            1       /* Assassin 3D */
#define A3D_MODE_PAN            2       /* Panther */
#define A3D_MODE_OEM            3       /* Panther OEM version */
#define A3D_MODE_PXL            4       /* Panther XL */

static char *a3d_names[] = { NULL, "FP-Gaming Assassin 3D", "MadCatz Panther", "OEM Panther",
                        "MadCatz Panther XL", "MadCatz Panther XL w/ rudder" };

struct a3d {
        struct gameport *gameport;
        struct gameport *adc;
        struct input_dev *dev;
        int axes[4];
        int buttons;
        int mode;
        int length;
        int reads;
        int bads;
        char phys[32];
};

/*
 * a3d_read_packet() reads an Assassin 3D packet.
 */

static int a3d_read_packet(struct gameport *gameport, int length, char *data)
{
        unsigned long flags;
        unsigned char u, v;
        unsigned int t, s;
        int i;

        i = 0;
        t = gameport_time(gameport, A3D_MAX_START);
        s = gameport_time(gameport, A3D_MAX_STROBE);

        local_irq_save(flags);
        gameport_trigger(gameport);
        v = gameport_read(gameport);

        while (t > 0 && i < length) {
                t--;
                u = v; v = gameport_read(gameport);
                if (~v & u & 0x10) {
                        data[i++] = v >> 5;
                        t = s;
                }
        }

        local_irq_restore(flags);

        return i;
}

/*
 * a3d_csum() computes checksum of triplet packet
 */

static int a3d_csum(char *data, int count)
{
        int i, csum = 0;

        for (i = 0; i < count - 2; i++)
                csum += data[i];
        return (csum & 0x3f) != ((data[count - 2] << 3) | data[count - 1]);
}

static void a3d_read(struct a3d *a3d, unsigned char *data)
{
        struct input_dev *dev = a3d->dev;

        switch (a3d->mode) {

                case A3D_MODE_A3D:
                case A3D_MODE_OEM:
                case A3D_MODE_PAN:

                        input_report_rel(dev, REL_X, ((data[5] << 6) | (data[6] << 3) | data[ 7]) - ((data[5] & 4) << 7));
                        input_report_rel(dev, REL_Y, ((data[8] << 6) | (data[9] << 3) | data[10]) - ((data[8] & 4) << 7));

                        input_report_key(dev, BTN_RIGHT,  data[2] & 1);
                        input_report_key(dev, BTN_LEFT,   data[3] & 2);
                        input_report_key(dev, BTN_MIDDLE, data[3] & 4);

                        input_sync(dev);

                        a3d->axes[0] = ((signed char)((data[11] << 6) | (data[12] << 3) | (data[13]))) + 128;
                        a3d->axes[1] = ((signed char)((data[14] << 6) | (data[15] << 3) | (data[16]))) + 128;
                        a3d->axes[2] = ((signed char)((data[17] << 6) | (data[18] << 3) | (data[19]))) + 128;
                        a3d->axes[3] = ((signed char)((data[20] << 6) | (data[21] << 3) | (data[22]))) + 128;

                        a3d->buttons = ((data[3] << 3) | data[4]) & 0xf;

                        break;

                case A3D_MODE_PXL:

                        input_report_rel(dev, REL_X, ((data[ 9] << 6) | (data[10] << 3) | data[11]) - ((data[ 9] & 4) << 7));
                        input_report_rel(dev, REL_Y, ((data[12] << 6) | (data[13] << 3) | data[14]) - ((data[12] & 4) << 7));

                        input_report_key(dev, BTN_RIGHT,  data[2] & 1);
                        input_report_key(dev, BTN_LEFT,   data[3] & 2);
                        input_report_key(dev, BTN_MIDDLE, data[3] & 4);
                        input_report_key(dev, BTN_SIDE,   data[7] & 2);
                        input_report_key(dev, BTN_EXTRA,  data[7] & 4);

                        input_report_abs(dev, ABS_X,        ((signed char)((data[15] << 6) | (data[16] << 3) | (data[17]))) + 128);
                        input_report_abs(dev, ABS_Y,        ((signed char)((data[18] << 6) | (data[19] << 3) | (data[20]))) + 128);
                        input_report_abs(dev, ABS_RUDDER,   ((signed char)((data[21] << 6) | (data[22] << 3) | (data[23]))) + 128);
                        input_report_abs(dev, ABS_THROTTLE, ((signed char)((data[24] << 6) | (data[25] << 3) | (data[26]))) + 128);

                        input_report_abs(dev, ABS_HAT0X, ( data[5]       & 1) - ((data[5] >> 2) & 1));
                        input_report_abs(dev, ABS_HAT0Y, ((data[5] >> 1) & 1) - ((data[6] >> 2) & 1));
                        input_report_abs(dev, ABS_HAT1X, ((data[4] >> 1) & 1) - ( data[3]       & 1));
                        input_report_abs(dev, ABS_HAT1Y, ((data[4] >> 2) & 1) - ( data[4]       & 1));

                        input_report_key(dev, BTN_TRIGGER, data[8] & 1);
                        input_report_key(dev, BTN_THUMB,   data[8] & 2);
                        input_report_key(dev, BTN_TOP,     data[8] & 4);
                        input_report_key(dev, BTN_PINKIE,  data[7] & 1);

                        input_sync(dev);

                        break;
        }
}


/*
 * a3d_poll() reads and analyzes A3D joystick data.
 */

static void a3d_poll(struct gameport *gameport)
{
        struct a3d *a3d = gameport_get_drvdata(gameport);
        unsigned char data[A3D_MAX_LENGTH];

        a3d->reads++;
        if (a3d_read_packet(a3d->gameport, a3d->length, data) != a3d->length ||
            data[0] != a3d->mode || a3d_csum(data, a3d->length))
                a3d->bads++;
        else
                a3d_read(a3d, data);
}

/*
 * a3d_adc_cooked_read() copies the acis and button data to the
 * callers arrays. It could do the read itself, but the caller could
 * call this more than 50 times a second, which would use too much CPU.
 */

static int a3d_adc_cooked_read(struct gameport *gameport, int *axes, int *buttons)
{
        struct a3d *a3d = gameport->port_data;
        int i;

        for (i = 0; i < 4; i++)
                axes[i] = (a3d->axes[i] < 254) ? a3d->axes[i] : -1;
        *buttons = a3d->buttons;
        return 0;
}

/*
 * a3d_adc_open() is the gameport open routine. It refuses to serve
 * any but cooked data.
 */

static int a3d_adc_open(struct gameport *gameport, int mode)
{
        struct a3d *a3d = gameport->port_data;

        if (mode != GAMEPORT_MODE_COOKED)
                return -1;

        gameport_start_polling(a3d->gameport);
        return 0;
}

/*
 * a3d_adc_close() is a callback from the input close routine.
 */

static void a3d_adc_close(struct gameport *gameport)
{
        struct a3d *a3d = gameport->port_data;

        gameport_stop_polling(a3d->gameport);
}

/*
 * a3d_open() is a callback from the input open routine.
 */

static int a3d_open(struct input_dev *dev)
{
        struct a3d *a3d = input_get_drvdata(dev);

        gameport_start_polling(a3d->gameport);
        return 0;
}

/*
 * a3d_close() is a callback from the input close routine.
 */

static void a3d_close(struct input_dev *dev)
{
        struct a3d *a3d = input_get_drvdata(dev);

        gameport_stop_polling(a3d->gameport);
}

/*
 * a3d_connect() probes for A3D joysticks.
 */

static int a3d_connect(struct gameport *gameport, struct gameport_driver *drv)
{
        struct a3d *a3d;
        struct input_dev *input_dev;
        struct gameport *adc;
        unsigned char data[A3D_MAX_LENGTH];
        int i;
        int err;

        a3d = kzalloc_obj(*a3d);
        input_dev = input_allocate_device();
        if (!a3d || !input_dev) {
                err = -ENOMEM;
                goto fail1;
        }

        a3d->dev = input_dev;
        a3d->gameport = gameport;

        gameport_set_drvdata(gameport, a3d);

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

        i = a3d_read_packet(gameport, A3D_MAX_LENGTH, data);

        if (!i || a3d_csum(data, i)) {
                err = -ENODEV;
                goto fail2;
        }

        a3d->mode = data[0];

        if (!a3d->mode || a3d->mode > 5) {
                printk(KERN_WARNING "a3d.c: Unknown A3D device detected "
                        "(%s, id=%d), contact <vojtech@ucw.cz>\n", gameport->phys, a3d->mode);
                err = -ENODEV;
                goto fail2;
        }

        gameport_set_poll_handler(gameport, a3d_poll);
        gameport_set_poll_interval(gameport, 20);

        snprintf(a3d->phys, sizeof(a3d->phys), "%s/input0", gameport->phys);

        input_dev->name = a3d_names[a3d->mode];
        input_dev->phys = a3d->phys;
        input_dev->id.bustype = BUS_GAMEPORT;
        input_dev->id.vendor = GAMEPORT_ID_VENDOR_MADCATZ;
        input_dev->id.product = a3d->mode;
        input_dev->id.version = 0x0100;
        input_dev->dev.parent = &gameport->dev;
        input_dev->open = a3d_open;
        input_dev->close = a3d_close;

        input_set_drvdata(input_dev, a3d);

        if (a3d->mode == A3D_MODE_PXL) {

                int axes[] = { ABS_X, ABS_Y, ABS_THROTTLE, ABS_RUDDER };

                a3d->length = 33;

                input_dev->evbit[0] |= BIT_MASK(EV_ABS) | BIT_MASK(EV_KEY) |
                        BIT_MASK(EV_REL);
                input_dev->relbit[0] |= BIT_MASK(REL_X) | BIT_MASK(REL_Y);
                input_dev->absbit[0] |= BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) |
                        BIT_MASK(ABS_THROTTLE) | BIT_MASK(ABS_RUDDER) |
                        BIT_MASK(ABS_HAT0X) | BIT_MASK(ABS_HAT0Y) |
                        BIT_MASK(ABS_HAT1X) | BIT_MASK(ABS_HAT1Y);
                input_dev->keybit[BIT_WORD(BTN_MOUSE)] |= BIT_MASK(BTN_RIGHT) |
                        BIT_MASK(BTN_LEFT) | BIT_MASK(BTN_MIDDLE) |
                        BIT_MASK(BTN_SIDE) | BIT_MASK(BTN_EXTRA);
                input_dev->keybit[BIT_WORD(BTN_JOYSTICK)] |=
                        BIT_MASK(BTN_TRIGGER) | BIT_MASK(BTN_THUMB) |
                        BIT_MASK(BTN_TOP) | BIT_MASK(BTN_PINKIE);

                a3d_read(a3d, data);

                for (i = 0; i < 4; i++) {
                        if (i < 2)
                                input_set_abs_params(input_dev, axes[i],
                                        48, input_abs_get_val(input_dev, axes[i]) * 2 - 48, 0, 8);
                        else
                                input_set_abs_params(input_dev, axes[i], 2, 253, 0, 0);
                        input_set_abs_params(input_dev, ABS_HAT0X + i, -1, 1, 0, 0);
                }

        } else {
                a3d->length = 29;

                input_dev->evbit[0] |= BIT_MASK(EV_KEY) | BIT_MASK(EV_REL);
                input_dev->relbit[0] |= BIT_MASK(REL_X) | BIT_MASK(REL_Y);
                input_dev->keybit[BIT_WORD(BTN_MOUSE)] |= BIT_MASK(BTN_RIGHT) |
                        BIT_MASK(BTN_LEFT) | BIT_MASK(BTN_MIDDLE);

                a3d_read(a3d, data);

                if (!(a3d->adc = adc = gameport_allocate_port()))
                        printk(KERN_ERR "a3d: Not enough memory for ADC port\n");
                else {
                        adc->port_data = a3d;
                        adc->open = a3d_adc_open;
                        adc->close = a3d_adc_close;
                        adc->cooked_read = a3d_adc_cooked_read;
                        adc->fuzz = 1;

                        gameport_set_name(adc, a3d_names[a3d->mode]);
                        gameport_set_phys(adc, "%s/gameport0", gameport->phys);
                        adc->dev.parent = &gameport->dev;

                        gameport_register_port(adc);
                }
        }

        err = input_register_device(a3d->dev);
        if (err)
                goto fail3;

        return 0;

 fail3: if (a3d->adc)
                gameport_unregister_port(a3d->adc);
 fail2: gameport_close(gameport);
 fail1: gameport_set_drvdata(gameport, NULL);
        input_free_device(input_dev);
        kfree(a3d);
        return err;
}

static void a3d_disconnect(struct gameport *gameport)
{
        struct a3d *a3d = gameport_get_drvdata(gameport);

        input_unregister_device(a3d->dev);
        if (a3d->adc)
                gameport_unregister_port(a3d->adc);
        gameport_close(gameport);
        gameport_set_drvdata(gameport, NULL);
        kfree(a3d);
}

static struct gameport_driver a3d_drv = {
        .driver         = {
                .name   = "adc",
                .owner  = THIS_MODULE,
        },
        .description    = DRIVER_DESC,
        .connect        = a3d_connect,
        .disconnect     = a3d_disconnect,
};

module_gameport_driver(a3d_drv);