// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * serial_ir.c
 *
 * serial_ir - Device driver that records pulse- and pause-lengths
 *             (space-lengths) between DDCD event on a serial port.
 *
 * Copyright (C) 1996,97 Ralph Metzler <rjkm@thp.uni-koeln.de>
 * Copyright (C) 1998 Trent Piepho <xyzzy@u.washington.edu>
 * Copyright (C) 1998 Ben Pfaff <blp@gnu.org>
 * Copyright (C) 1999 Christoph Bartelmus <lirc@bartelmus.de>
 * Copyright (C) 2007 Andrei Tanas <andrei@tanas.ca> (suspend/resume support)
 * Copyright (C) 2016 Sean Young <sean@mess.org> (port to rc-core)
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/serial_reg.h>
#include <linux/types.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include <media/rc-core.h>

struct serial_ir_hw {
        int signal_pin;
        int signal_pin_change;
        u8 on;
        u8 off;
        unsigned set_send_carrier:1;
        unsigned set_duty_cycle:1;
        void (*send_pulse)(unsigned int length, ktime_t edge);
        void (*send_space)(void);
        spinlock_t lock;
};

#define IR_HOMEBREW     0
#define IR_IRDEO        1
#define IR_IRDEO_REMOTE 2
#define IR_ANIMAX       3
#define IR_IGOR         4

/* module parameters */
static int type;
static int io;
static int irq;
static ulong iommap;
static int ioshift;
static bool softcarrier = true;
static bool share_irq;
static int sense = -1;  /* -1 = auto, 0 = active high, 1 = active low */
static bool txsense;    /* 0 = active high, 1 = active low */

/* forward declarations */
static void send_pulse_irdeo(unsigned int length, ktime_t edge);
static void send_space_irdeo(void);
#ifdef CONFIG_IR_SERIAL_TRANSMITTER
static void send_pulse_homebrew(unsigned int length, ktime_t edge);
static void send_space_homebrew(void);
#endif

static struct serial_ir_hw hardware[] = {
        [IR_HOMEBREW] = {
                .lock = __SPIN_LOCK_UNLOCKED(hardware[IR_HOMEBREW].lock),
                .signal_pin        = UART_MSR_DCD,
                .signal_pin_change = UART_MSR_DDCD,
                .on  = (UART_MCR_RTS | UART_MCR_OUT2 | UART_MCR_DTR),
                .off = (UART_MCR_RTS | UART_MCR_OUT2),
#ifdef CONFIG_IR_SERIAL_TRANSMITTER
                .send_pulse = send_pulse_homebrew,
                .send_space = send_space_homebrew,
                .set_send_carrier = true,
                .set_duty_cycle = true,
#endif
        },

        [IR_IRDEO] = {
                .lock = __SPIN_LOCK_UNLOCKED(hardware[IR_IRDEO].lock),
                .signal_pin        = UART_MSR_DSR,
                .signal_pin_change = UART_MSR_DDSR,
                .on  = UART_MCR_OUT2,
                .off = (UART_MCR_RTS | UART_MCR_DTR | UART_MCR_OUT2),
                .send_pulse = send_pulse_irdeo,
                .send_space = send_space_irdeo,
                .set_duty_cycle = true,
        },

        [IR_IRDEO_REMOTE] = {
                .lock = __SPIN_LOCK_UNLOCKED(hardware[IR_IRDEO_REMOTE].lock),
                .signal_pin        = UART_MSR_DSR,
                .signal_pin_change = UART_MSR_DDSR,
                .on  = (UART_MCR_RTS | UART_MCR_DTR | UART_MCR_OUT2),
                .off = (UART_MCR_RTS | UART_MCR_DTR | UART_MCR_OUT2),
                .send_pulse = send_pulse_irdeo,
                .send_space = send_space_irdeo,
                .set_duty_cycle = true,
        },

        [IR_ANIMAX] = {
                .lock = __SPIN_LOCK_UNLOCKED(hardware[IR_ANIMAX].lock),
                .signal_pin        = UART_MSR_DCD,
                .signal_pin_change = UART_MSR_DDCD,
                .on  = 0,
                .off = (UART_MCR_RTS | UART_MCR_DTR | UART_MCR_OUT2),
        },

        [IR_IGOR] = {
                .lock = __SPIN_LOCK_UNLOCKED(hardware[IR_IGOR].lock),
                .signal_pin        = UART_MSR_DSR,
                .signal_pin_change = UART_MSR_DDSR,
                .on  = (UART_MCR_RTS | UART_MCR_OUT2 | UART_MCR_DTR),
                .off = (UART_MCR_RTS | UART_MCR_OUT2),
#ifdef CONFIG_IR_SERIAL_TRANSMITTER
                .send_pulse = send_pulse_homebrew,
                .send_space = send_space_homebrew,
                .set_send_carrier = true,
                .set_duty_cycle = true,
#endif
        },
};

#define RS_ISR_PASS_LIMIT 256

struct serial_ir {
        ktime_t lastkt;
        struct rc_dev *rcdev;
        struct platform_device *pdev;
        struct timer_list timeout_timer;

        unsigned int carrier;
        unsigned int duty_cycle;
};

static struct serial_ir serial_ir;

/* fetch serial input packet (1 byte) from register offset */
static u8 sinp(int offset)
{
        if (iommap)
                /* the register is memory-mapped */
                offset <<= ioshift;

        return inb(io + offset);
}

/* write serial output packet (1 byte) of value to register offset */
static void soutp(int offset, u8 value)
{
        if (iommap)
                /* the register is memory-mapped */
                offset <<= ioshift;

        outb(value, io + offset);
}

static void on(void)
{
        if (txsense)
                soutp(UART_MCR, hardware[type].off);
        else
                soutp(UART_MCR, hardware[type].on);
}

static void off(void)
{
        if (txsense)
                soutp(UART_MCR, hardware[type].on);
        else
                soutp(UART_MCR, hardware[type].off);
}

static void send_pulse_irdeo(unsigned int length, ktime_t target)
{
        long rawbits;
        int i;
        unsigned char output;
        unsigned char chunk, shifted;

        /* how many bits have to be sent ? */
        rawbits = length * 1152 / 10000;
        if (serial_ir.duty_cycle > 50)
                chunk = 3;
        else
                chunk = 1;
        for (i = 0, output = 0x7f; rawbits > 0; rawbits -= 3) {
                shifted = chunk << (i * 3);
                shifted >>= 1;
                output &= (~shifted);
                i++;
                if (i == 3) {
                        soutp(UART_TX, output);
                        while (!(sinp(UART_LSR) & UART_LSR_THRE))
                                ;
                        output = 0x7f;
                        i = 0;
                }
        }
        if (i != 0) {
                soutp(UART_TX, output);
                while (!(sinp(UART_LSR) & UART_LSR_TEMT))
                        ;
        }
}

static void send_space_irdeo(void)
{
}

#ifdef CONFIG_IR_SERIAL_TRANSMITTER
static void send_pulse_homebrew_softcarrier(unsigned int length, ktime_t edge)
{
        ktime_t now, target = ktime_add_us(edge, length);
        /*
         * delta should never exceed 4 seconds and on m68k
         * ndelay(s64) does not compile; so use s32 rather than s64.
         */
        s32 delta;
        unsigned int pulse, space;

        /* Ensure the dividend fits into 32 bit */
        pulse = DIV_ROUND_CLOSEST(serial_ir.duty_cycle * (NSEC_PER_SEC / 100),
                                  serial_ir.carrier);
        space = DIV_ROUND_CLOSEST((100 - serial_ir.duty_cycle) *
                                  (NSEC_PER_SEC / 100), serial_ir.carrier);

        for (;;) {
                now = ktime_get();
                if (ktime_compare(now, target) >= 0)
                        break;
                on();
                edge = ktime_add_ns(edge, pulse);
                delta = ktime_to_ns(ktime_sub(edge, now));
                if (delta > 0)
                        ndelay(delta);
                now = ktime_get();
                off();
                if (ktime_compare(now, target) >= 0)
                        break;
                edge = ktime_add_ns(edge, space);
                delta = ktime_to_ns(ktime_sub(edge, now));
                if (delta > 0)
                        ndelay(delta);
        }
}

static void send_pulse_homebrew(unsigned int length, ktime_t edge)
{
        if (softcarrier)
                send_pulse_homebrew_softcarrier(length, edge);
        else
                on();
}

static void send_space_homebrew(void)
{
        off();
}
#endif

static void frbwrite(unsigned int l, bool is_pulse)
{
        /* simple noise filter */
        static unsigned int ptr, pulse, space;
        struct ir_raw_event ev = {};

        if (ptr > 0 && is_pulse) {
                pulse += l;
                if (pulse > 250) {
                        ev.duration = space;
                        ev.pulse = false;
                        ir_raw_event_store_with_filter(serial_ir.rcdev, &ev);
                        ev.duration = pulse;
                        ev.pulse = true;
                        ir_raw_event_store_with_filter(serial_ir.rcdev, &ev);
                        ptr = 0;
                        pulse = 0;
                }
                return;
        }
        if (!is_pulse) {
                if (ptr == 0) {
                        if (l > 20000) {
                                space = l;
                                ptr++;
                                return;
                        }
                } else {
                        if (l > 20000) {
                                space += pulse;
                                if (space > IR_MAX_DURATION)
                                        space = IR_MAX_DURATION;
                                space += l;
                                if (space > IR_MAX_DURATION)
                                        space = IR_MAX_DURATION;
                                pulse = 0;
                                return;
                        }

                        ev.duration = space;
                        ev.pulse = false;
                        ir_raw_event_store_with_filter(serial_ir.rcdev, &ev);
                        ev.duration = pulse;
                        ev.pulse = true;
                        ir_raw_event_store_with_filter(serial_ir.rcdev, &ev);
                        ptr = 0;
                        pulse = 0;
                }
        }

        ev.duration = l;
        ev.pulse = is_pulse;
        ir_raw_event_store_with_filter(serial_ir.rcdev, &ev);
}

static irqreturn_t serial_ir_irq_handler(int i, void *blah)
{
        ktime_t kt;
        int counter, dcd;
        u8 status;
        ktime_t delkt;
        unsigned int data;
        static int last_dcd = -1;

        if ((sinp(UART_IIR) & UART_IIR_NO_INT)) {
                /* not our interrupt */
                return IRQ_NONE;
        }

        counter = 0;
        do {
                counter++;
                status = sinp(UART_MSR);
                if (counter > RS_ISR_PASS_LIMIT) {
                        dev_err(&serial_ir.pdev->dev, "Trapped in interrupt");
                        break;
                }
                if ((status & hardware[type].signal_pin_change) &&
                    sense != -1) {
                        /* get current time */
                        kt = ktime_get();

                        /*
                         * The driver needs to know if your receiver is
                         * active high or active low, or the space/pulse
                         * sense could be inverted.
                         */

                        /* calc time since last interrupt in nanoseconds */
                        dcd = (status & hardware[type].signal_pin) ? 1 : 0;

                        if (dcd == last_dcd) {
                                dev_dbg(&serial_ir.pdev->dev,
                                        "ignoring spike: %d %d %lldns %lldns\n",
                                        dcd, sense, ktime_to_ns(kt),
                                        ktime_to_ns(serial_ir.lastkt));
                                continue;
                        }

                        delkt = ktime_sub(kt, serial_ir.lastkt);
                        if (ktime_compare(delkt, ktime_set(15, 0)) > 0) {
                                data = IR_MAX_DURATION; /* really long time */
                                if (!(dcd ^ sense)) {
                                        /* sanity check */
                                        dev_err(&serial_ir.pdev->dev,
                                                "dcd unexpected: %d %d %lldns %lldns\n",
                                                dcd, sense, ktime_to_ns(kt),
                                                ktime_to_ns(serial_ir.lastkt));
                                        /*
                                         * detecting pulse while this
                                         * MUST be a space!
                                         */
                                        sense = sense ? 0 : 1;
                                }
                        } else {
                                data = ktime_to_us(delkt);
                        }
                        frbwrite(data, !(dcd ^ sense));
                        serial_ir.lastkt = kt;
                        last_dcd = dcd;
                }
        } while (!(sinp(UART_IIR) & UART_IIR_NO_INT)); /* still pending ? */

        mod_timer(&serial_ir.timeout_timer,
                  jiffies + usecs_to_jiffies(serial_ir.rcdev->timeout));

        ir_raw_event_handle(serial_ir.rcdev);

        return IRQ_HANDLED;
}

static int hardware_init_port(void)
{
        u8 scratch, scratch2, scratch3;

        /*
         * This is a simple port existence test, borrowed from the autoconfig
         * function in drivers/tty/serial/8250/8250_port.c
         */
        scratch = sinp(UART_IER);
        soutp(UART_IER, 0);
#ifdef __i386__
        outb(0xff, 0x080);
#endif
        scratch2 = sinp(UART_IER) & 0x0f;
        soutp(UART_IER, 0x0f);
#ifdef __i386__
        outb(0x00, 0x080);
#endif
        scratch3 = sinp(UART_IER) & 0x0f;
        soutp(UART_IER, scratch);
        if (scratch2 != 0 || scratch3 != 0x0f) {
                /* we fail, there's nothing here */
                pr_err("port existence test failed, cannot continue\n");
                return -ENODEV;
        }

        /* Set DLAB 0. */
        soutp(UART_LCR, sinp(UART_LCR) & (~UART_LCR_DLAB));

        /* First of all, disable all interrupts */
        soutp(UART_IER, sinp(UART_IER) &
              (~(UART_IER_MSI | UART_IER_RLSI | UART_IER_THRI | UART_IER_RDI)));

        /* Clear registers. */
        sinp(UART_LSR);
        sinp(UART_RX);
        sinp(UART_IIR);
        sinp(UART_MSR);

        /* Set line for power source */
        off();

        /* Clear registers again to be sure. */
        sinp(UART_LSR);
        sinp(UART_RX);
        sinp(UART_IIR);
        sinp(UART_MSR);

        switch (type) {
        case IR_IRDEO:
        case IR_IRDEO_REMOTE:
                /* setup port to 7N1 @ 115200 Baud */
                /* 7N1+start = 9 bits at 115200 ~ 3 bits at 38kHz */

                /* Set DLAB 1. */
                soutp(UART_LCR, sinp(UART_LCR) | UART_LCR_DLAB);
                /* Set divisor to 1 => 115200 Baud */
                soutp(UART_DLM, 0);
                soutp(UART_DLL, 1);
                /* Set DLAB 0 +  7N1 */
                soutp(UART_LCR, UART_LCR_WLEN7);
                /* THR interrupt already disabled at this point */
                break;
        default:
                break;
        }

        return 0;
}

static void serial_ir_timeout(struct timer_list *unused)
{
        struct ir_raw_event ev = {
                .timeout = true,
                .duration = serial_ir.rcdev->timeout
        };
        ir_raw_event_store_with_filter(serial_ir.rcdev, &ev);
        ir_raw_event_handle(serial_ir.rcdev);
}

/* Needed by serial_ir_probe() */
static int serial_ir_tx(struct rc_dev *dev, unsigned int *txbuf,
                        unsigned int count);
static int serial_ir_tx_duty_cycle(struct rc_dev *dev, u32 cycle);
static int serial_ir_tx_carrier(struct rc_dev *dev, u32 carrier);
static int serial_ir_open(struct rc_dev *rcdev);
static void serial_ir_close(struct rc_dev *rcdev);

static int serial_ir_probe(struct platform_device *dev)
{
        struct rc_dev *rcdev;
        int i, nlow, nhigh, result;

        rcdev = devm_rc_allocate_device(&dev->dev, RC_DRIVER_IR_RAW);
        if (!rcdev)
                return -ENOMEM;

        if (hardware[type].send_pulse && hardware[type].send_space)
                rcdev->tx_ir = serial_ir_tx;
        if (hardware[type].set_send_carrier)
                rcdev->s_tx_carrier = serial_ir_tx_carrier;
        if (hardware[type].set_duty_cycle)
                rcdev->s_tx_duty_cycle = serial_ir_tx_duty_cycle;

        switch (type) {
        case IR_HOMEBREW:
                rcdev->device_name = "Serial IR type home-brew";
                break;
        case IR_IRDEO:
                rcdev->device_name = "Serial IR type IRdeo";
                break;
        case IR_IRDEO_REMOTE:
                rcdev->device_name = "Serial IR type IRdeo remote";
                break;
        case IR_ANIMAX:
                rcdev->device_name = "Serial IR type AnimaX";
                break;
        case IR_IGOR:
                rcdev->device_name = "Serial IR type IgorPlug";
                break;
        }

        rcdev->input_phys = KBUILD_MODNAME "/input0";
        rcdev->input_id.bustype = BUS_HOST;
        rcdev->input_id.vendor = 0x0001;
        rcdev->input_id.product = 0x0001;
        rcdev->input_id.version = 0x0100;
        rcdev->open = serial_ir_open;
        rcdev->close = serial_ir_close;
        rcdev->dev.parent = &serial_ir.pdev->dev;
        rcdev->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
        rcdev->driver_name = KBUILD_MODNAME;
        rcdev->map_name = RC_MAP_RC6_MCE;
        rcdev->min_timeout = 1;
        rcdev->timeout = IR_DEFAULT_TIMEOUT;
        rcdev->max_timeout = 10 * IR_DEFAULT_TIMEOUT;
        rcdev->rx_resolution = 250;

        serial_ir.rcdev = rcdev;

        timer_setup(&serial_ir.timeout_timer, serial_ir_timeout, 0);

        result = devm_request_irq(&dev->dev, irq, serial_ir_irq_handler,
                                  share_irq ? IRQF_SHARED : 0,
                                  KBUILD_MODNAME, &hardware);
        if (result < 0) {
                if (result == -EBUSY)
                        dev_err(&dev->dev, "IRQ %d busy\n", irq);
                else if (result == -EINVAL)
                        dev_err(&dev->dev, "Bad irq number or handler\n");
                return result;
        }

        /* Reserve io region. */
        if ((iommap &&
             (devm_request_mem_region(&dev->dev, iommap, 8UL << ioshift,
                                      KBUILD_MODNAME) == NULL)) ||
             (!iommap && (devm_request_region(&dev->dev, io, 8,
                          KBUILD_MODNAME) == NULL))) {
                dev_err(&dev->dev, "port %04x already in use\n", io);
                dev_warn(&dev->dev, "use 'setserial /dev/ttySX uart none'\n");
                dev_warn(&dev->dev,
                         "or compile the serial port driver as module and\n");
                dev_warn(&dev->dev, "make sure this module is loaded first\n");
                return -EBUSY;
        }

        result = hardware_init_port();
        if (result < 0)
                return result;

        /* Initialize pulse/space widths */
        serial_ir.duty_cycle = 50;
        serial_ir.carrier = 38000;

        /* If pin is high, then this must be an active low receiver. */
        if (sense == -1) {
                /* wait 1/2 sec for the power supply */
                msleep(500);

                /*
                 * probe 9 times every 0.04s, collect "votes" for
                 * active high/low
                 */
                nlow = 0;
                nhigh = 0;
                for (i = 0; i < 9; i++) {
                        if (sinp(UART_MSR) & hardware[type].signal_pin)
                                nlow++;
                        else
                                nhigh++;
                        msleep(40);
                }
                sense = nlow >= nhigh ? 1 : 0;
                dev_info(&dev->dev, "auto-detected active %s receiver\n",
                         sense ? "low" : "high");
        } else
                dev_info(&dev->dev, "Manually using active %s receiver\n",
                         sense ? "low" : "high");

        dev_dbg(&dev->dev, "Interrupt %d, port %04x obtained\n", irq, io);

        return devm_rc_register_device(&dev->dev, rcdev);
}

static int serial_ir_open(struct rc_dev *rcdev)
{
        unsigned long flags;

        /* initialize timestamp */
        serial_ir.lastkt = ktime_get();

        spin_lock_irqsave(&hardware[type].lock, flags);

        /* Set DLAB 0. */
        soutp(UART_LCR, sinp(UART_LCR) & (~UART_LCR_DLAB));

        soutp(UART_IER, sinp(UART_IER) | UART_IER_MSI);

        spin_unlock_irqrestore(&hardware[type].lock, flags);

        return 0;
}

static void serial_ir_close(struct rc_dev *rcdev)
{
        unsigned long flags;

        spin_lock_irqsave(&hardware[type].lock, flags);

        /* Set DLAB 0. */
        soutp(UART_LCR, sinp(UART_LCR) & (~UART_LCR_DLAB));

        /* First of all, disable all interrupts */
        soutp(UART_IER, sinp(UART_IER) &
              (~(UART_IER_MSI | UART_IER_RLSI | UART_IER_THRI | UART_IER_RDI)));
        spin_unlock_irqrestore(&hardware[type].lock, flags);
}

static int serial_ir_tx(struct rc_dev *dev, unsigned int *txbuf,
                        unsigned int count)
{
        unsigned long flags;
        ktime_t edge;
        s64 delta;
        int i;

        spin_lock_irqsave(&hardware[type].lock, flags);
        if (type == IR_IRDEO) {
                /* DTR, RTS down */
                on();
        }

        edge = ktime_get();
        for (i = 0; i < count; i++) {
                if (i % 2)
                        hardware[type].send_space();
                else
                        hardware[type].send_pulse(txbuf[i], edge);

                edge = ktime_add_us(edge, txbuf[i]);
                delta = ktime_us_delta(edge, ktime_get());
                if (delta > 25) {
                        spin_unlock_irqrestore(&hardware[type].lock, flags);
                        usleep_range(delta - 25, delta + 25);
                        spin_lock_irqsave(&hardware[type].lock, flags);
                } else if (delta > 0) {
                        udelay(delta);
                }
        }
        off();
        spin_unlock_irqrestore(&hardware[type].lock, flags);
        return count;
}

static int serial_ir_tx_duty_cycle(struct rc_dev *dev, u32 cycle)
{
        serial_ir.duty_cycle = cycle;
        return 0;
}

static int serial_ir_tx_carrier(struct rc_dev *dev, u32 carrier)
{
        if (carrier > 500000 || carrier < 20000)
                return -EINVAL;

        serial_ir.carrier = carrier;
        return 0;
}

static int serial_ir_suspend(struct platform_device *dev,
                             pm_message_t state)
{
        /* Set DLAB 0. */
        soutp(UART_LCR, sinp(UART_LCR) & (~UART_LCR_DLAB));

        /* Disable all interrupts */
        soutp(UART_IER, sinp(UART_IER) &
              (~(UART_IER_MSI | UART_IER_RLSI | UART_IER_THRI | UART_IER_RDI)));

        /* Clear registers. */
        sinp(UART_LSR);
        sinp(UART_RX);
        sinp(UART_IIR);
        sinp(UART_MSR);

        return 0;
}

static int serial_ir_resume(struct platform_device *dev)
{
        unsigned long flags;
        int result;

        result = hardware_init_port();
        if (result < 0)
                return result;

        spin_lock_irqsave(&hardware[type].lock, flags);
        /* Enable Interrupt */
        serial_ir.lastkt = ktime_get();
        soutp(UART_IER, sinp(UART_IER) | UART_IER_MSI);
        off();

        spin_unlock_irqrestore(&hardware[type].lock, flags);

        return 0;
}

static struct platform_driver serial_ir_driver = {
        .probe          = serial_ir_probe,
        .suspend        = serial_ir_suspend,
        .resume         = serial_ir_resume,
        .driver         = {
                .name   = "serial_ir",
        },
};

static int __init serial_ir_init(void)
{
        int result;

        result = platform_driver_register(&serial_ir_driver);
        if (result)
                return result;

        serial_ir.pdev = platform_device_alloc("serial_ir", 0);
        if (!serial_ir.pdev) {
                result = -ENOMEM;
                goto exit_driver_unregister;
        }

        result = platform_device_add(serial_ir.pdev);
        if (result)
                goto exit_device_put;

        return 0;

exit_device_put:
        platform_device_put(serial_ir.pdev);
exit_driver_unregister:
        platform_driver_unregister(&serial_ir_driver);
        return result;
}

static void serial_ir_exit(void)
{
        platform_device_unregister(serial_ir.pdev);
        platform_driver_unregister(&serial_ir_driver);
}

static int __init serial_ir_init_module(void)
{
        switch (type) {
        case IR_HOMEBREW:
        case IR_IRDEO:
        case IR_IRDEO_REMOTE:
        case IR_ANIMAX:
        case IR_IGOR:
                /* if nothing specified, use ttyS0/com1 and irq 4 */
                io = io ? io : 0x3f8;
                irq = irq ? irq : 4;
                break;
        default:
                return -EINVAL;
        }
        if (!softcarrier) {
                switch (type) {
                case IR_HOMEBREW:
                case IR_IGOR:
                        hardware[type].set_send_carrier = false;
                        hardware[type].set_duty_cycle = false;
                        break;
                }
        }

        /* make sure sense is either -1, 0, or 1 */
        if (sense != -1)
                sense = !!sense;

        return serial_ir_init();
}

static void __exit serial_ir_exit_module(void)
{
        timer_delete_sync(&serial_ir.timeout_timer);
        serial_ir_exit();
}

module_init(serial_ir_init_module);
module_exit(serial_ir_exit_module);

MODULE_DESCRIPTION("Infra-red receiver driver for serial ports.");
MODULE_AUTHOR("Ralph Metzler, Trent Piepho, Ben Pfaff, Christoph Bartelmus, Andrei Tanas");
MODULE_LICENSE("GPL");

module_param(type, int, 0444);
MODULE_PARM_DESC(type, "Hardware type (0 = home-brew, 1 = IRdeo, 2 = IRdeo Remote, 3 = AnimaX, 4 = IgorPlug");

module_param_hw(io, int, ioport, 0444);
MODULE_PARM_DESC(io, "I/O address base (0x3f8 or 0x2f8)");

/* some architectures (e.g. intel xscale) have memory mapped registers */
module_param_hw(iommap, ulong, other, 0444);
MODULE_PARM_DESC(iommap, "physical base for memory mapped I/O (0 = no memory mapped io)");

/*
 * some architectures (e.g. intel xscale) align the 8bit serial registers
 * on 32bit word boundaries.
 * See linux-kernel/drivers/tty/serial/8250/8250.c serial_in()/out()
 */
module_param_hw(ioshift, int, other, 0444);
MODULE_PARM_DESC(ioshift, "shift I/O register offset (0 = no shift)");

module_param_hw(irq, int, irq, 0444);
MODULE_PARM_DESC(irq, "Interrupt (4 or 3)");

module_param_hw(share_irq, bool, other, 0444);
MODULE_PARM_DESC(share_irq, "Share interrupts (0 = off, 1 = on)");

module_param(sense, int, 0444);
MODULE_PARM_DESC(sense, "Override autodetection of IR receiver circuit (0 = active high, 1 = active low )");

#ifdef CONFIG_IR_SERIAL_TRANSMITTER
module_param(txsense, bool, 0444);
MODULE_PARM_DESC(txsense, "Sense of transmitter circuit (0 = active high, 1 = active low )");
#endif

module_param(softcarrier, bool, 0444);
MODULE_PARM_DESC(softcarrier, "Software carrier (0 = off, 1 = on, default on)");