// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Copyright (c) 1996-2001 Vojtech Pavlik
 */

/*
 * This is just a very simple driver that can dump the data
 * out of the joystick port into the syslog ...
 */

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

#define DRIVER_DESC     "Gameport data dumper module"

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

#define BUF_SIZE 256

struct joydump {
        unsigned int time;
        unsigned char data;
};

static int joydump_connect(struct gameport *gameport, struct gameport_driver *drv)
{
        struct joydump *buf;    /* all entries */
        struct joydump *dump, *prev;    /* one entry each */
        int axes[4], buttons;
        int i, j, t, timeout;
        unsigned long flags;
        unsigned char u;

        printk(KERN_INFO "joydump: ,------------------ START ----------------.\n");
        printk(KERN_INFO "joydump: | Dumping: %30s |\n", gameport->phys);
        printk(KERN_INFO "joydump: | Speed: %28d kHz |\n", gameport->speed);

        if (gameport_open(gameport, drv, GAMEPORT_MODE_RAW)) {

                printk(KERN_INFO "joydump: | Raw mode not available - trying cooked.    |\n");

                if (gameport_open(gameport, drv, GAMEPORT_MODE_COOKED)) {

                        printk(KERN_INFO "joydump: | Cooked not available either. Failing.   |\n");
                        printk(KERN_INFO "joydump: `------------------- END -----------------'\n");
                        return -ENODEV;
                }

                gameport_cooked_read(gameport, axes, &buttons);

                for (i = 0; i < 4; i++)
                        printk(KERN_INFO "joydump: | Axis %d: %4d.                           |\n", i, axes[i]);
                printk(KERN_INFO "joydump: | Buttons %02x.                             |\n", buttons);
                printk(KERN_INFO "joydump: `------------------- END -----------------'\n");
        }

        timeout = gameport_time(gameport, 10000); /* 10 ms */

        buf = kmalloc_objs(struct joydump, BUF_SIZE);
        if (!buf) {
                printk(KERN_INFO "joydump: no memory for testing\n");
                goto jd_end;
        }
        dump = buf;
        t = 0;
        i = 1;

        local_irq_save(flags);

        u = gameport_read(gameport);

        dump->data = u;
        dump->time = t;
        dump++;

        gameport_trigger(gameport);

        while (i < BUF_SIZE && t < timeout) {

                dump->data = gameport_read(gameport);

                if (dump->data ^ u) {
                        u = dump->data;
                        dump->time = t;
                        i++;
                        dump++;
                }
                t++;
        }

        local_irq_restore(flags);

/*
 * Dump data.
 */

        t = i;
        dump = buf;
        prev = dump;

        printk(KERN_INFO "joydump: >------------------ DATA -----------------<\n");
        printk(KERN_INFO "joydump: | index: %3d delta: %3d us data: ", 0, 0);
        for (j = 7; j >= 0; j--)
                printk("%d", (dump->data >> j) & 1);
        printk(" |\n");
        dump++;

        for (i = 1; i < t; i++, dump++, prev++) {
                printk(KERN_INFO "joydump: | index: %3d delta: %3d us data: ",
                        i, dump->time - prev->time);
                for (j = 7; j >= 0; j--)
                        printk("%d", (dump->data >> j) & 1);
                printk(" |\n");
        }
        kfree(buf);

jd_end:
        printk(KERN_INFO "joydump: `------------------- END -----------------'\n");

        return 0;
}

static void joydump_disconnect(struct gameport *gameport)
{
        gameport_close(gameport);
}

static struct gameport_driver joydump_drv = {
        .driver         = {
                .name   = "joydump",
        },
        .description    = DRIVER_DESC,
        .connect        = joydump_connect,
        .disconnect     = joydump_disconnect,
};

module_gameport_driver(joydump_drv);