// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Copyright (c) 1999-2001 Vojtech Pavlik
 *
 *  Based on the work of:
 *      David Thompson
 */

/*
 * SpaceTec SpaceOrb 360 and Avenger 6dof controller driver for Linux
 */

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

#define DRIVER_DESC     "SpaceTec SpaceOrb 360 and Avenger 6dof controller driver"

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

/*
 * Constants.
 */

#define SPACEORB_MAX_LENGTH     64

static int spaceorb_buttons[] = { BTN_TL, BTN_TR, BTN_Y, BTN_X, BTN_B, BTN_A };
static int spaceorb_axes[] = { ABS_X, ABS_Y, ABS_Z, ABS_RX, ABS_RY, ABS_RZ };

/*
 * Per-Orb data.
 */

struct spaceorb {
        struct input_dev *dev;
        int idx;
        unsigned char data[SPACEORB_MAX_LENGTH];
        char phys[32];
};

static unsigned char spaceorb_xor[] = "SpaceWare";

static unsigned char *spaceorb_errors[] = { "EEPROM storing 0 failed", "Receive queue overflow", "Transmit queue timeout",
                "Bad packet", "Power brown-out", "EEPROM checksum error", "Hardware fault" };

/*
 * spaceorb_process_packet() decodes packets the driver receives from the
 * SpaceOrb.
 */

static void spaceorb_process_packet(struct spaceorb *spaceorb)
{
        struct input_dev *dev = spaceorb->dev;
        unsigned char *data = spaceorb->data;
        unsigned char c = 0;
        int axes[6];
        int i;

        if (spaceorb->idx < 2) return;
        for (i = 0; i < spaceorb->idx; i++) c ^= data[i];
        if (c) return;

        switch (data[0]) {

                case 'R':                               /* Reset packet */
                        spaceorb->data[spaceorb->idx - 1] = 0;
                        for (i = 1; i < spaceorb->idx && spaceorb->data[i] == ' '; i++);
                        printk(KERN_INFO "input: %s [%s] is %s\n",
                                 dev->name, spaceorb->data + i, spaceorb->phys);
                        break;

                case 'D':                               /* Ball + button data */
                        if (spaceorb->idx != 12) return;
                        for (i = 0; i < 9; i++) spaceorb->data[i+2] ^= spaceorb_xor[i];
                        axes[0] = ( data[2]      << 3) | (data[ 3] >> 4);
                        axes[1] = ((data[3] & 0x0f) << 6) | (data[ 4] >> 1);
                        axes[2] = ((data[4] & 0x01) << 9) | (data[ 5] << 2) | (data[4] >> 5);
                        axes[3] = ((data[6] & 0x1f) << 5) | (data[ 7] >> 2);
                        axes[4] = ((data[7] & 0x03) << 8) | (data[ 8] << 1) | (data[7] >> 6);
                        axes[5] = ((data[9] & 0x3f) << 4) | (data[10] >> 3);
                        for (i = 0; i < 6; i++)
                                input_report_abs(dev, spaceorb_axes[i], axes[i] - ((axes[i] & 0x200) ? 1024 : 0));
                        for (i = 0; i < 6; i++)
                                input_report_key(dev, spaceorb_buttons[i], (data[1] >> i) & 1);
                        break;

                case 'K':                               /* Button data */
                        if (spaceorb->idx != 5) return;
                        for (i = 0; i < 6; i++)
                                input_report_key(dev, spaceorb_buttons[i], (data[2] >> i) & 1);

                        break;

                case 'E':                               /* Error packet */
                        if (spaceorb->idx != 4) return;
                        printk(KERN_ERR "spaceorb: Device error. [ ");
                        for (i = 0; i < 7; i++) if (data[1] & (1 << i)) printk("%s ", spaceorb_errors[i]);
                        printk("]\n");
                        break;
        }

        input_sync(dev);
}

static irqreturn_t spaceorb_interrupt(struct serio *serio,
                unsigned char data, unsigned int flags)
{
        struct spaceorb* spaceorb = serio_get_drvdata(serio);

        if (~data & 0x80) {
                if (spaceorb->idx) spaceorb_process_packet(spaceorb);
                spaceorb->idx = 0;
        }
        if (spaceorb->idx < SPACEORB_MAX_LENGTH)
                spaceorb->data[spaceorb->idx++] = data & 0x7f;
        return IRQ_HANDLED;
}

/*
 * spaceorb_disconnect() is the opposite of spaceorb_connect()
 */

static void spaceorb_disconnect(struct serio *serio)
{
        struct spaceorb* spaceorb = serio_get_drvdata(serio);

        serio_close(serio);
        serio_set_drvdata(serio, NULL);
        input_unregister_device(spaceorb->dev);
        kfree(spaceorb);
}

/*
 * spaceorb_connect() is the routine that is called when someone adds a
 * new serio device that supports SpaceOrb/Avenger protocol and registers
 * it as an input device.
 */

static int spaceorb_connect(struct serio *serio, struct serio_driver *drv)
{
        struct spaceorb *spaceorb;
        struct input_dev *input_dev;
        int err = -ENOMEM;
        int i;

        spaceorb = kzalloc_obj(*spaceorb);
        input_dev = input_allocate_device();
        if (!spaceorb || !input_dev)
                goto fail1;

        spaceorb->dev = input_dev;
        snprintf(spaceorb->phys, sizeof(spaceorb->phys), "%s/input0", serio->phys);

        input_dev->name = "SpaceTec SpaceOrb 360 / Avenger";
        input_dev->phys = spaceorb->phys;
        input_dev->id.bustype = BUS_RS232;
        input_dev->id.vendor = SERIO_SPACEORB;
        input_dev->id.product = 0x0001;
        input_dev->id.version = 0x0100;
        input_dev->dev.parent = &serio->dev;

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

        for (i = 0; i < 6; i++)
                set_bit(spaceorb_buttons[i], input_dev->keybit);

        for (i = 0; i < 6; i++)
                input_set_abs_params(input_dev, spaceorb_axes[i], -508, 508, 0, 0);

        serio_set_drvdata(serio, spaceorb);

        err = serio_open(serio, drv);
        if (err)
                goto fail2;

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

        return 0;

 fail3: serio_close(serio);
 fail2: serio_set_drvdata(serio, NULL);
 fail1: input_free_device(input_dev);
        kfree(spaceorb);
        return err;
}

/*
 * The serio driver structure.
 */

static const struct serio_device_id spaceorb_serio_ids[] = {
        {
                .type   = SERIO_RS232,
                .proto  = SERIO_SPACEORB,
                .id     = SERIO_ANY,
                .extra  = SERIO_ANY,
        },
        { 0 }
};

MODULE_DEVICE_TABLE(serio, spaceorb_serio_ids);

static struct serio_driver spaceorb_drv = {
        .driver         = {
                .name   = "spaceorb",
        },
        .description    = DRIVER_DESC,
        .id_table       = spaceorb_serio_ids,
        .interrupt      = spaceorb_interrupt,
        .connect        = spaceorb_connect,
        .disconnect     = spaceorb_disconnect,
};

module_serio_driver(spaceorb_drv);