// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Driver for ITE Tech Inc. IT8712F/IT8512 CIR
 *
 * Copyright (C) 2010 Juan Jesús García de Soria <skandalfo@gmail.com>
 *
 * Inspired by the original lirc_it87 and lirc_ite8709 drivers, on top of the
 * skeleton provided by the nuvoton-cir driver.
 *
 * The lirc_it87 driver was originally written by Hans-Gunter Lutke Uphues
 * <hg_lu@web.de> in 2001, with enhancements by Christoph Bartelmus
 * <lirc@bartelmus.de>, Andrew Calkin <r_tay@hotmail.com> and James Edwards
 * <jimbo-lirc@edwardsclan.net>.
 *
 * The lirc_ite8709 driver was written by Grégory Lardière
 * <spmf2004-lirc@yahoo.fr> in 2008.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pnp.h>
#include <linux/io.h>
#include <linux/interrupt.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/bitops.h>
#include <media/rc-core.h>
#include <linux/pci_ids.h>

#include "ite-cir.h"

/* module parameters */

/* debug level */
static int debug;
module_param(debug, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Enable debugging output");

/* low limit for RX carrier freq, Hz, 0 for no RX demodulation */
static int rx_low_carrier_freq;
module_param(rx_low_carrier_freq, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(rx_low_carrier_freq, "Override low RX carrier frequency, Hz, 0 for no RX demodulation");

/* high limit for RX carrier freq, Hz, 0 for no RX demodulation */
static int rx_high_carrier_freq;
module_param(rx_high_carrier_freq, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(rx_high_carrier_freq, "Override high RX carrier frequency, Hz, 0 for no RX demodulation");

/* override tx carrier frequency */
static int tx_carrier_freq;
module_param(tx_carrier_freq, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(tx_carrier_freq, "Override TX carrier frequency, Hz");

/* override tx duty cycle */
static int tx_duty_cycle;
module_param(tx_duty_cycle, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(tx_duty_cycle, "Override TX duty cycle, 1-100");

/* override default sample period */
static long sample_period;
module_param(sample_period, long, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(sample_period, "Override carrier sample period, us");

/* override detected model id */
static int model_number = -1;
module_param(model_number, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(model_number, "Use this model number, don't autodetect");


/* HW-independent code functions */

/* check whether carrier frequency is high frequency */
static inline bool ite_is_high_carrier_freq(unsigned int freq)
{
        return freq >= ITE_HCF_MIN_CARRIER_FREQ;
}

/* get the bits required to program the carrier frequency in CFQ bits,
 * unshifted */
static u8 ite_get_carrier_freq_bits(unsigned int freq)
{
        if (ite_is_high_carrier_freq(freq)) {
                if (freq < 425000)
                        return ITE_CFQ_400;

                else if (freq < 465000)
                        return ITE_CFQ_450;

                else if (freq < 490000)
                        return ITE_CFQ_480;

                else
                        return ITE_CFQ_500;
        } else {
                        /* trim to limits */
                if (freq < ITE_LCF_MIN_CARRIER_FREQ)
                        freq = ITE_LCF_MIN_CARRIER_FREQ;
                if (freq > ITE_LCF_MAX_CARRIER_FREQ)
                        freq = ITE_LCF_MAX_CARRIER_FREQ;

                /* convert to kHz and subtract the base freq */
                freq =
                    DIV_ROUND_CLOSEST(freq - ITE_LCF_MIN_CARRIER_FREQ,
                                      1000);

                return (u8) freq;
        }
}

/* get the bits required to program the pulse with in TXMPW */
static u8 ite_get_pulse_width_bits(unsigned int freq, int duty_cycle)
{
        unsigned long period_ns, on_ns;

        /* sanitize freq into range */
        if (freq < ITE_LCF_MIN_CARRIER_FREQ)
                freq = ITE_LCF_MIN_CARRIER_FREQ;
        if (freq > ITE_HCF_MAX_CARRIER_FREQ)
                freq = ITE_HCF_MAX_CARRIER_FREQ;

        period_ns = 1000000000UL / freq;
        on_ns = period_ns * duty_cycle / 100;

        if (ite_is_high_carrier_freq(freq)) {
                if (on_ns < 750)
                        return ITE_TXMPW_A;

                else if (on_ns < 850)
                        return ITE_TXMPW_B;

                else if (on_ns < 950)
                        return ITE_TXMPW_C;

                else if (on_ns < 1080)
                        return ITE_TXMPW_D;

                else
                        return ITE_TXMPW_E;
        } else {
                if (on_ns < 6500)
                        return ITE_TXMPW_A;

                else if (on_ns < 7850)
                        return ITE_TXMPW_B;

                else if (on_ns < 9650)
                        return ITE_TXMPW_C;

                else if (on_ns < 11950)
                        return ITE_TXMPW_D;

                else
                        return ITE_TXMPW_E;
        }
}

/* decode raw bytes as received by the hardware, and push them to the ir-core
 * layer */
static void ite_decode_bytes(struct ite_dev *dev, const u8 * data, int
                             length)
{
        u32 sample_period;
        unsigned long *ldata;
        unsigned int next_one, next_zero, size;
        struct ir_raw_event ev = {};

        if (length == 0)
                return;

        sample_period = dev->params.sample_period;
        ldata = (unsigned long *)data;
        size = length << 3;
        next_one = find_next_bit_le(ldata, size, 0);
        if (next_one > 0) {
                ev.pulse = true;
                ev.duration =
                    ITE_BITS_TO_NS(next_one, sample_period);
                ir_raw_event_store_with_filter(dev->rdev, &ev);
        }

        while (next_one < size) {
                next_zero = find_next_zero_bit_le(ldata, size, next_one + 1);
                ev.pulse = false;
                ev.duration = ITE_BITS_TO_NS(next_zero - next_one, sample_period);
                ir_raw_event_store_with_filter(dev->rdev, &ev);

                if (next_zero < size) {
                        next_one =
                            find_next_bit_le(ldata,
                                                     size,
                                                     next_zero + 1);
                        ev.pulse = true;
                        ev.duration =
                            ITE_BITS_TO_NS(next_one - next_zero,
                                           sample_period);
                        ir_raw_event_store_with_filter
                            (dev->rdev, &ev);
                } else
                        next_one = size;
        }

        ir_raw_event_handle(dev->rdev);

        ite_dbg_verbose("decoded %d bytes.", length);
}

/* set all the rx/tx carrier parameters; this must be called with the device
 * spinlock held */
static void ite_set_carrier_params(struct ite_dev *dev)
{
        unsigned int freq, low_freq, high_freq;
        int allowance;
        bool use_demodulator;
        bool for_tx = dev->transmitting;

        ite_dbg("%s called", __func__);

        if (for_tx) {
                /* we don't need no stinking calculations */
                freq = dev->params.tx_carrier_freq;
                allowance = ITE_RXDCR_DEFAULT;
                use_demodulator = false;
        } else {
                low_freq = dev->params.rx_low_carrier_freq;
                high_freq = dev->params.rx_high_carrier_freq;

                if (low_freq == 0) {
                        /* don't demodulate */
                        freq =
                        ITE_DEFAULT_CARRIER_FREQ;
                        allowance = ITE_RXDCR_DEFAULT;
                        use_demodulator = false;
                } else {
                        /* calculate the middle freq */
                        freq = (low_freq + high_freq) / 2;

                        /* calculate the allowance */
                        allowance =
                            DIV_ROUND_CLOSEST(10000 * (high_freq - low_freq),
                                              ITE_RXDCR_PER_10000_STEP
                                              * (high_freq + low_freq));

                        if (allowance < 1)
                                allowance = 1;

                        if (allowance > ITE_RXDCR_MAX)
                                allowance = ITE_RXDCR_MAX;

                        use_demodulator = true;
                }
        }

        /* set the carrier parameters in a device-dependent way */
        dev->params.set_carrier_params(dev, ite_is_high_carrier_freq(freq),
                 use_demodulator, ite_get_carrier_freq_bits(freq), allowance,
                 ite_get_pulse_width_bits(freq, dev->params.tx_duty_cycle));
}

/* interrupt service routine for incoming and outgoing CIR data */
static irqreturn_t ite_cir_isr(int irq, void *data)
{
        struct ite_dev *dev = data;
        unsigned long flags;
        irqreturn_t ret = IRQ_RETVAL(IRQ_NONE);
        u8 rx_buf[ITE_RX_FIFO_LEN];
        int rx_bytes;
        int iflags;

        ite_dbg_verbose("%s firing", __func__);

        /* grab the spinlock */
        spin_lock_irqsave(&dev->lock, flags);

        /* read the interrupt flags */
        iflags = dev->params.get_irq_causes(dev);

        /* check for the receive interrupt */
        if (iflags & (ITE_IRQ_RX_FIFO | ITE_IRQ_RX_FIFO_OVERRUN)) {
                /* read the FIFO bytes */
                rx_bytes =
                        dev->params.get_rx_bytes(dev, rx_buf,
                                             ITE_RX_FIFO_LEN);

                if (rx_bytes > 0) {
                        /* drop the spinlock, since the ir-core layer
                         * may call us back again through
                         * ite_s_idle() */
                        spin_unlock_irqrestore(&dev->
                                                                         lock,
                                                                         flags);

                        /* decode the data we've just received */
                        ite_decode_bytes(dev, rx_buf,
                                                                   rx_bytes);

                        /* reacquire the spinlock */
                        spin_lock_irqsave(&dev->lock,
                                                                    flags);

                        /* mark the interrupt as serviced */
                        ret = IRQ_RETVAL(IRQ_HANDLED);
                }
        } else if (iflags & ITE_IRQ_TX_FIFO) {
                /* FIFO space available interrupt */
                ite_dbg_verbose("got interrupt for TX FIFO");

                /* wake any sleeping transmitter */
                wake_up_interruptible(&dev->tx_queue);

                /* mark the interrupt as serviced */
                ret = IRQ_RETVAL(IRQ_HANDLED);
        }

        /* drop the spinlock */
        spin_unlock_irqrestore(&dev->lock, flags);

        ite_dbg_verbose("%s done returning %d", __func__, (int)ret);

        return ret;
}

/* set the rx carrier freq range, guess it's in Hz... */
static int ite_set_rx_carrier_range(struct rc_dev *rcdev, u32 carrier_low, u32
                                    carrier_high)
{
        unsigned long flags;
        struct ite_dev *dev = rcdev->priv;

        spin_lock_irqsave(&dev->lock, flags);
        dev->params.rx_low_carrier_freq = carrier_low;
        dev->params.rx_high_carrier_freq = carrier_high;
        ite_set_carrier_params(dev);
        spin_unlock_irqrestore(&dev->lock, flags);

        return 0;
}

/* set the tx carrier freq, guess it's in Hz... */
static int ite_set_tx_carrier(struct rc_dev *rcdev, u32 carrier)
{
        unsigned long flags;
        struct ite_dev *dev = rcdev->priv;

        spin_lock_irqsave(&dev->lock, flags);
        dev->params.tx_carrier_freq = carrier;
        ite_set_carrier_params(dev);
        spin_unlock_irqrestore(&dev->lock, flags);

        return 0;
}

/* set the tx duty cycle by controlling the pulse width */
static int ite_set_tx_duty_cycle(struct rc_dev *rcdev, u32 duty_cycle)
{
        unsigned long flags;
        struct ite_dev *dev = rcdev->priv;

        spin_lock_irqsave(&dev->lock, flags);
        dev->params.tx_duty_cycle = duty_cycle;
        ite_set_carrier_params(dev);
        spin_unlock_irqrestore(&dev->lock, flags);

        return 0;
}

/* transmit out IR pulses; what you get here is a batch of alternating
 * pulse/space/pulse/space lengths that we should write out completely through
 * the FIFO, blocking on a full FIFO */
static int ite_tx_ir(struct rc_dev *rcdev, unsigned *txbuf, unsigned n)
{
        unsigned long flags;
        struct ite_dev *dev = rcdev->priv;
        bool is_pulse = false;
        int remaining_us, fifo_avail, fifo_remaining, last_idx = 0;
        int max_rle_us, next_rle_us;
        int ret = n;
        u8 last_sent[ITE_TX_FIFO_LEN];
        u8 val;

        ite_dbg("%s called", __func__);

        /* clear the array just in case */
        memset(last_sent, 0, sizeof(last_sent));

        spin_lock_irqsave(&dev->lock, flags);

        /* let everybody know we're now transmitting */
        dev->transmitting = true;

        /* and set the carrier values for transmission */
        ite_set_carrier_params(dev);

        /* calculate how much time we can send in one byte */
        max_rle_us =
            (ITE_BAUDRATE_DIVISOR * dev->params.sample_period *
             ITE_TX_MAX_RLE) / 1000;

        /* disable the receiver */
        dev->params.disable_rx(dev);

        /* this is where we'll begin filling in the FIFO, until it's full.
         * then we'll just activate the interrupt, wait for it to wake us up
         * again, disable it, continue filling the FIFO... until everything
         * has been pushed out */
        fifo_avail =
            ITE_TX_FIFO_LEN - dev->params.get_tx_used_slots(dev);

        while (n > 0 && dev->in_use) {
                /* transmit the next sample */
                is_pulse = !is_pulse;
                remaining_us = *(txbuf++);
                n--;

                ite_dbg("%s: %ld",
                                      ((is_pulse) ? "pulse" : "space"),
                                      (long int)
                                      remaining_us);

                /* repeat while the pulse is non-zero length */
                while (remaining_us > 0 && dev->in_use) {
                        if (remaining_us > max_rle_us)
                                next_rle_us = max_rle_us;

                        else
                                next_rle_us = remaining_us;

                        remaining_us -= next_rle_us;

                        /* check what's the length we have to pump out */
                        val = (ITE_TX_MAX_RLE * next_rle_us) / max_rle_us;

                        /* put it into the sent buffer */
                        last_sent[last_idx++] = val;
                        last_idx &= (ITE_TX_FIFO_LEN);

                        /* encode it for 7 bits */
                        val = (val - 1) & ITE_TX_RLE_MASK;

                        /* take into account pulse/space prefix */
                        if (is_pulse)
                                val |= ITE_TX_PULSE;

                        else
                                val |= ITE_TX_SPACE;

                        /*
                         * if we get to 0 available, read again, just in case
                         * some other slot got freed
                         */
                        if (fifo_avail <= 0)
                                fifo_avail = ITE_TX_FIFO_LEN - dev->params.get_tx_used_slots(dev);

                        /* if it's still full */
                        if (fifo_avail <= 0) {
                                /* enable the tx interrupt */
                                dev->params.
                                enable_tx_interrupt(dev);

                                /* drop the spinlock */
                                spin_unlock_irqrestore(&dev->lock, flags);

                                /* wait for the FIFO to empty enough */
                                wait_event_interruptible(dev->tx_queue, (fifo_avail = ITE_TX_FIFO_LEN - dev->params.get_tx_used_slots(dev)) >= 8);

                                /* get the spinlock again */
                                spin_lock_irqsave(&dev->lock, flags);

                                /* disable the tx interrupt again. */
                                dev->params.
                                disable_tx_interrupt(dev);
                        }

                        /* now send the byte through the FIFO */
                        dev->params.put_tx_byte(dev, val);
                        fifo_avail--;
                }
        }

        /* wait and don't return until the whole FIFO has been sent out;
         * otherwise we could configure the RX carrier params instead of the
         * TX ones while the transmission is still being performed! */
        fifo_remaining = dev->params.get_tx_used_slots(dev);
        remaining_us = 0;
        while (fifo_remaining > 0) {
                fifo_remaining--;
                last_idx--;
                last_idx &= (ITE_TX_FIFO_LEN - 1);
                remaining_us += last_sent[last_idx];
        }
        remaining_us = (remaining_us * max_rle_us) / (ITE_TX_MAX_RLE);

        /* drop the spinlock while we sleep */
        spin_unlock_irqrestore(&dev->lock, flags);

        /* sleep remaining_us microseconds */
        mdelay(DIV_ROUND_UP(remaining_us, 1000));

        /* reacquire the spinlock */
        spin_lock_irqsave(&dev->lock, flags);

        /* now we're not transmitting anymore */
        dev->transmitting = false;

        /* and set the carrier values for reception */
        ite_set_carrier_params(dev);

        /* re-enable the receiver */
        if (dev->in_use)
                dev->params.enable_rx(dev);

        /* notify transmission end */
        wake_up_interruptible(&dev->tx_ended);

        spin_unlock_irqrestore(&dev->lock, flags);

        return ret;
}

/* idle the receiver if needed */
static void ite_s_idle(struct rc_dev *rcdev, bool enable)
{
        unsigned long flags;
        struct ite_dev *dev = rcdev->priv;

        ite_dbg("%s called", __func__);

        if (enable) {
                spin_lock_irqsave(&dev->lock, flags);
                dev->params.idle_rx(dev);
                spin_unlock_irqrestore(&dev->lock, flags);
        }
}


/* IT8712F HW-specific functions */

/* retrieve a bitmask of the current causes for a pending interrupt; this may
 * be composed of ITE_IRQ_TX_FIFO, ITE_IRQ_RX_FIFO and ITE_IRQ_RX_FIFO_OVERRUN
 * */
static int it87_get_irq_causes(struct ite_dev *dev)
{
        u8 iflags;
        int ret = 0;

        ite_dbg("%s called", __func__);

        /* read the interrupt flags */
        iflags = inb(dev->cir_addr + IT87_IIR) & IT87_II;

        switch (iflags) {
        case IT87_II_RXDS:
                ret = ITE_IRQ_RX_FIFO;
                break;
        case IT87_II_RXFO:
                ret = ITE_IRQ_RX_FIFO_OVERRUN;
                break;
        case IT87_II_TXLDL:
                ret = ITE_IRQ_TX_FIFO;
                break;
        }

        return ret;
}

/* set the carrier parameters; to be called with the spinlock held */
static void it87_set_carrier_params(struct ite_dev *dev, bool high_freq,
                                    bool use_demodulator,
                                    u8 carrier_freq_bits, u8 allowance_bits,
                                    u8 pulse_width_bits)
{
        u8 val;

        ite_dbg("%s called", __func__);

        /* program the RCR register */
        val = inb(dev->cir_addr + IT87_RCR)
                & ~(IT87_HCFS | IT87_RXEND | IT87_RXDCR);

        if (high_freq)
                val |= IT87_HCFS;

        if (use_demodulator)
                val |= IT87_RXEND;

        val |= allowance_bits;

        outb(val, dev->cir_addr + IT87_RCR);

        /* program the TCR2 register */
        outb((carrier_freq_bits << IT87_CFQ_SHIFT) | pulse_width_bits,
                dev->cir_addr + IT87_TCR2);
}

/* read up to buf_size bytes from the RX FIFO; to be called with the spinlock
 * held */
static int it87_get_rx_bytes(struct ite_dev *dev, u8 * buf, int buf_size)
{
        int fifo, read = 0;

        ite_dbg("%s called", __func__);

        /* read how many bytes are still in the FIFO */
        fifo = inb(dev->cir_addr + IT87_RSR) & IT87_RXFBC;

        while (fifo > 0 && buf_size > 0) {
                *(buf++) = inb(dev->cir_addr + IT87_DR);
                fifo--;
                read++;
                buf_size--;
        }

        return read;
}

/* return how many bytes are still in the FIFO; this will be called
 * with the device spinlock NOT HELD while waiting for the TX FIFO to get
 * empty; let's expect this won't be a problem */
static int it87_get_tx_used_slots(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        return inb(dev->cir_addr + IT87_TSR) & IT87_TXFBC;
}

/* put a byte to the TX fifo; this should be called with the spinlock held */
static void it87_put_tx_byte(struct ite_dev *dev, u8 value)
{
        outb(value, dev->cir_addr + IT87_DR);
}

/* idle the receiver so that we won't receive samples until another
  pulse is detected; this must be called with the device spinlock held */
static void it87_idle_rx(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* disable streaming by clearing RXACT writing it as 1 */
        outb(inb(dev->cir_addr + IT87_RCR) | IT87_RXACT,
                dev->cir_addr + IT87_RCR);

        /* clear the FIFO */
        outb(inb(dev->cir_addr + IT87_TCR1) | IT87_FIFOCLR,
                dev->cir_addr + IT87_TCR1);
}

/* disable the receiver; this must be called with the device spinlock held */
static void it87_disable_rx(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* disable the receiver interrupts */
        outb(inb(dev->cir_addr + IT87_IER) & ~(IT87_RDAIE | IT87_RFOIE),
                dev->cir_addr + IT87_IER);

        /* disable the receiver */
        outb(inb(dev->cir_addr + IT87_RCR) & ~IT87_RXEN,
                dev->cir_addr + IT87_RCR);

        /* clear the FIFO and RXACT (actually RXACT should have been cleared
        * in the previous outb() call) */
        it87_idle_rx(dev);
}

/* enable the receiver; this must be called with the device spinlock held */
static void it87_enable_rx(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* enable the receiver by setting RXEN */
        outb(inb(dev->cir_addr + IT87_RCR) | IT87_RXEN,
                dev->cir_addr + IT87_RCR);

        /* just prepare it to idle for the next reception */
        it87_idle_rx(dev);

        /* enable the receiver interrupts and master enable flag */
        outb(inb(dev->cir_addr + IT87_IER) | IT87_RDAIE | IT87_RFOIE | IT87_IEC,
                dev->cir_addr + IT87_IER);
}

/* disable the transmitter interrupt; this must be called with the device
 * spinlock held */
static void it87_disable_tx_interrupt(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* disable the transmitter interrupts */
        outb(inb(dev->cir_addr + IT87_IER) & ~IT87_TLDLIE,
                dev->cir_addr + IT87_IER);
}

/* enable the transmitter interrupt; this must be called with the device
 * spinlock held */
static void it87_enable_tx_interrupt(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* enable the transmitter interrupts and master enable flag */
        outb(inb(dev->cir_addr + IT87_IER) | IT87_TLDLIE | IT87_IEC,
                dev->cir_addr + IT87_IER);
}

/* disable the device; this must be called with the device spinlock held */
static void it87_disable(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* clear out all interrupt enable flags */
        outb(inb(dev->cir_addr + IT87_IER) &
                ~(IT87_IEC | IT87_RFOIE | IT87_RDAIE | IT87_TLDLIE),
                dev->cir_addr + IT87_IER);

        /* disable the receiver */
        it87_disable_rx(dev);

        /* erase the FIFO */
        outb(IT87_FIFOCLR | inb(dev->cir_addr + IT87_TCR1),
                dev->cir_addr + IT87_TCR1);
}

/* initialize the hardware */
static void it87_init_hardware(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* enable just the baud rate divisor register,
        disabling all the interrupts at the same time */
        outb((inb(dev->cir_addr + IT87_IER) &
                ~(IT87_IEC | IT87_RFOIE | IT87_RDAIE | IT87_TLDLIE)) | IT87_BR,
                dev->cir_addr + IT87_IER);

        /* write out the baud rate divisor */
        outb(ITE_BAUDRATE_DIVISOR & 0xff, dev->cir_addr + IT87_BDLR);
        outb((ITE_BAUDRATE_DIVISOR >> 8) & 0xff, dev->cir_addr + IT87_BDHR);

        /* disable the baud rate divisor register again */
        outb(inb(dev->cir_addr + IT87_IER) & ~IT87_BR,
                dev->cir_addr + IT87_IER);

        /* program the RCR register defaults */
        outb(ITE_RXDCR_DEFAULT, dev->cir_addr + IT87_RCR);

        /* program the TCR1 register */
        outb(IT87_TXMPM_DEFAULT | IT87_TXENDF | IT87_TXRLE
                | IT87_FIFOTL_DEFAULT | IT87_FIFOCLR,
                dev->cir_addr + IT87_TCR1);

        /* program the carrier parameters */
        ite_set_carrier_params(dev);
}

/* IT8512F on ITE8708 HW-specific functions */

/* retrieve a bitmask of the current causes for a pending interrupt; this may
 * be composed of ITE_IRQ_TX_FIFO, ITE_IRQ_RX_FIFO and ITE_IRQ_RX_FIFO_OVERRUN
 * */
static int it8708_get_irq_causes(struct ite_dev *dev)
{
        u8 iflags;
        int ret = 0;

        ite_dbg("%s called", __func__);

        /* read the interrupt flags */
        iflags = inb(dev->cir_addr + IT8708_C0IIR);

        if (iflags & IT85_TLDLI)
                ret |= ITE_IRQ_TX_FIFO;
        if (iflags & IT85_RDAI)
                ret |= ITE_IRQ_RX_FIFO;
        if (iflags & IT85_RFOI)
                ret |= ITE_IRQ_RX_FIFO_OVERRUN;

        return ret;
}

/* set the carrier parameters; to be called with the spinlock held */
static void it8708_set_carrier_params(struct ite_dev *dev, bool high_freq,
                                      bool use_demodulator,
                                      u8 carrier_freq_bits, u8 allowance_bits,
                                      u8 pulse_width_bits)
{
        u8 val;

        ite_dbg("%s called", __func__);

        /* program the C0CFR register, with HRAE=1 */
        outb(inb(dev->cir_addr + IT8708_BANKSEL) | IT8708_HRAE,
                dev->cir_addr + IT8708_BANKSEL);

        val = (inb(dev->cir_addr + IT8708_C0CFR)
                & ~(IT85_HCFS | IT85_CFQ)) | carrier_freq_bits;

        if (high_freq)
                val |= IT85_HCFS;

        outb(val, dev->cir_addr + IT8708_C0CFR);

        outb(inb(dev->cir_addr + IT8708_BANKSEL) & ~IT8708_HRAE,
                   dev->cir_addr + IT8708_BANKSEL);

        /* program the C0RCR register */
        val = inb(dev->cir_addr + IT8708_C0RCR)
                & ~(IT85_RXEND | IT85_RXDCR);

        if (use_demodulator)
                val |= IT85_RXEND;

        val |= allowance_bits;

        outb(val, dev->cir_addr + IT8708_C0RCR);

        /* program the C0TCR register */
        val = inb(dev->cir_addr + IT8708_C0TCR) & ~IT85_TXMPW;
        val |= pulse_width_bits;
        outb(val, dev->cir_addr + IT8708_C0TCR);
}

/* read up to buf_size bytes from the RX FIFO; to be called with the spinlock
 * held */
static int it8708_get_rx_bytes(struct ite_dev *dev, u8 * buf, int buf_size)
{
        int fifo, read = 0;

        ite_dbg("%s called", __func__);

        /* read how many bytes are still in the FIFO */
        fifo = inb(dev->cir_addr + IT8708_C0RFSR) & IT85_RXFBC;

        while (fifo > 0 && buf_size > 0) {
                *(buf++) = inb(dev->cir_addr + IT8708_C0DR);
                fifo--;
                read++;
                buf_size--;
        }

        return read;
}

/* return how many bytes are still in the FIFO; this will be called
 * with the device spinlock NOT HELD while waiting for the TX FIFO to get
 * empty; let's expect this won't be a problem */
static int it8708_get_tx_used_slots(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        return inb(dev->cir_addr + IT8708_C0TFSR) & IT85_TXFBC;
}

/* put a byte to the TX fifo; this should be called with the spinlock held */
static void it8708_put_tx_byte(struct ite_dev *dev, u8 value)
{
        outb(value, dev->cir_addr + IT8708_C0DR);
}

/* idle the receiver so that we won't receive samples until another
  pulse is detected; this must be called with the device spinlock held */
static void it8708_idle_rx(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* disable streaming by clearing RXACT writing it as 1 */
        outb(inb(dev->cir_addr + IT8708_C0RCR) | IT85_RXACT,
                dev->cir_addr + IT8708_C0RCR);

        /* clear the FIFO */
        outb(inb(dev->cir_addr + IT8708_C0MSTCR) | IT85_FIFOCLR,
                dev->cir_addr + IT8708_C0MSTCR);
}

/* disable the receiver; this must be called with the device spinlock held */
static void it8708_disable_rx(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* disable the receiver interrupts */
        outb(inb(dev->cir_addr + IT8708_C0IER) &
                ~(IT85_RDAIE | IT85_RFOIE),
                dev->cir_addr + IT8708_C0IER);

        /* disable the receiver */
        outb(inb(dev->cir_addr + IT8708_C0RCR) & ~IT85_RXEN,
                dev->cir_addr + IT8708_C0RCR);

        /* clear the FIFO and RXACT (actually RXACT should have been cleared
         * in the previous outb() call) */
        it8708_idle_rx(dev);
}

/* enable the receiver; this must be called with the device spinlock held */
static void it8708_enable_rx(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* enable the receiver by setting RXEN */
        outb(inb(dev->cir_addr + IT8708_C0RCR) | IT85_RXEN,
                dev->cir_addr + IT8708_C0RCR);

        /* just prepare it to idle for the next reception */
        it8708_idle_rx(dev);

        /* enable the receiver interrupts and master enable flag */
        outb(inb(dev->cir_addr + IT8708_C0IER)
                |IT85_RDAIE | IT85_RFOIE | IT85_IEC,
                dev->cir_addr + IT8708_C0IER);
}

/* disable the transmitter interrupt; this must be called with the device
 * spinlock held */
static void it8708_disable_tx_interrupt(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* disable the transmitter interrupts */
        outb(inb(dev->cir_addr + IT8708_C0IER) & ~IT85_TLDLIE,
                dev->cir_addr + IT8708_C0IER);
}

/* enable the transmitter interrupt; this must be called with the device
 * spinlock held */
static void it8708_enable_tx_interrupt(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* enable the transmitter interrupts and master enable flag */
        outb(inb(dev->cir_addr + IT8708_C0IER)
                |IT85_TLDLIE | IT85_IEC,
                dev->cir_addr + IT8708_C0IER);
}

/* disable the device; this must be called with the device spinlock held */
static void it8708_disable(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* clear out all interrupt enable flags */
        outb(inb(dev->cir_addr + IT8708_C0IER) &
                ~(IT85_IEC | IT85_RFOIE | IT85_RDAIE | IT85_TLDLIE),
                dev->cir_addr + IT8708_C0IER);

        /* disable the receiver */
        it8708_disable_rx(dev);

        /* erase the FIFO */
        outb(IT85_FIFOCLR | inb(dev->cir_addr + IT8708_C0MSTCR),
                dev->cir_addr + IT8708_C0MSTCR);
}

/* initialize the hardware */
static void it8708_init_hardware(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* disable all the interrupts */
        outb(inb(dev->cir_addr + IT8708_C0IER) &
                ~(IT85_IEC | IT85_RFOIE | IT85_RDAIE | IT85_TLDLIE),
                dev->cir_addr + IT8708_C0IER);

        /* program the baud rate divisor */
        outb(inb(dev->cir_addr + IT8708_BANKSEL) | IT8708_HRAE,
                dev->cir_addr + IT8708_BANKSEL);

        outb(ITE_BAUDRATE_DIVISOR & 0xff, dev->cir_addr + IT8708_C0BDLR);
        outb((ITE_BAUDRATE_DIVISOR >> 8) & 0xff,
                   dev->cir_addr + IT8708_C0BDHR);

        outb(inb(dev->cir_addr + IT8708_BANKSEL) & ~IT8708_HRAE,
                   dev->cir_addr + IT8708_BANKSEL);

        /* program the C0MSTCR register defaults */
        outb((inb(dev->cir_addr + IT8708_C0MSTCR) &
                        ~(IT85_ILSEL | IT85_ILE | IT85_FIFOTL |
                          IT85_FIFOCLR | IT85_RESET)) |
                       IT85_FIFOTL_DEFAULT,
                       dev->cir_addr + IT8708_C0MSTCR);

        /* program the C0RCR register defaults */
        outb((inb(dev->cir_addr + IT8708_C0RCR) &
                        ~(IT85_RXEN | IT85_RDWOS | IT85_RXEND |
                          IT85_RXACT | IT85_RXDCR)) |
                       ITE_RXDCR_DEFAULT,
                       dev->cir_addr + IT8708_C0RCR);

        /* program the C0TCR register defaults */
        outb((inb(dev->cir_addr + IT8708_C0TCR) &
                        ~(IT85_TXMPM | IT85_TXMPW))
                       |IT85_TXRLE | IT85_TXENDF |
                       IT85_TXMPM_DEFAULT | IT85_TXMPW_DEFAULT,
                       dev->cir_addr + IT8708_C0TCR);

        /* program the carrier parameters */
        ite_set_carrier_params(dev);
}

/* IT8512F on ITE8709 HW-specific functions */

/* read a byte from the SRAM module */
static inline u8 it8709_rm(struct ite_dev *dev, int index)

{
        outb(index, dev->cir_addr + IT8709_RAM_IDX);
        return inb(dev->cir_addr + IT8709_RAM_VAL);
}

/* write a byte to the SRAM module */
static inline void it8709_wm(struct ite_dev *dev, u8 val, int index)
{
        outb(index, dev->cir_addr + IT8709_RAM_IDX);
        outb(val, dev->cir_addr + IT8709_RAM_VAL);
}

static void it8709_wait(struct ite_dev *dev)
{
        int i = 0;
        /*
         * loop until device tells it's ready to continue
         * iterations count is usually ~750 but can sometimes achieve 13000
         */
        for (i = 0; i < 15000; i++) {
                udelay(2);
                if (it8709_rm(dev, IT8709_MODE) == IT8709_IDLE)
                        break;
        }
}

/* read the value of a CIR register */
static u8 it8709_rr(struct ite_dev *dev, int index)
{
        /* just wait in case the previous access was a write */
        it8709_wait(dev);
        it8709_wm(dev, index, IT8709_REG_IDX);
        it8709_wm(dev, IT8709_READ, IT8709_MODE);

        /* wait for the read data to be available */
        it8709_wait(dev);

        /* return the read value */
        return it8709_rm(dev, IT8709_REG_VAL);
}

/* write the value of a CIR register */
static void it8709_wr(struct ite_dev *dev, u8 val, int index)
{
        /* we wait before writing, and not afterwards, since this allows us to
         * pipeline the host CPU with the microcontroller */
        it8709_wait(dev);
        it8709_wm(dev, val, IT8709_REG_VAL);
        it8709_wm(dev, index, IT8709_REG_IDX);
        it8709_wm(dev, IT8709_WRITE, IT8709_MODE);
}

/* retrieve a bitmask of the current causes for a pending interrupt; this may
 * be composed of ITE_IRQ_TX_FIFO, ITE_IRQ_RX_FIFO and ITE_IRQ_RX_FIFO_OVERRUN
 * */
static int it8709_get_irq_causes(struct ite_dev *dev)
{
        u8 iflags;
        int ret = 0;

        ite_dbg("%s called", __func__);

        /* read the interrupt flags */
        iflags = it8709_rm(dev, IT8709_IIR);

        if (iflags & IT85_TLDLI)
                ret |= ITE_IRQ_TX_FIFO;
        if (iflags & IT85_RDAI)
                ret |= ITE_IRQ_RX_FIFO;
        if (iflags & IT85_RFOI)
                ret |= ITE_IRQ_RX_FIFO_OVERRUN;

        return ret;
}

/* set the carrier parameters; to be called with the spinlock held */
static void it8709_set_carrier_params(struct ite_dev *dev, bool high_freq,
                                      bool use_demodulator,
                                      u8 carrier_freq_bits, u8 allowance_bits,
                                      u8 pulse_width_bits)
{
        u8 val;

        ite_dbg("%s called", __func__);

        val = (it8709_rr(dev, IT85_C0CFR)
                     &~(IT85_HCFS | IT85_CFQ)) |
            carrier_freq_bits;

        if (high_freq)
                val |= IT85_HCFS;

        it8709_wr(dev, val, IT85_C0CFR);

        /* program the C0RCR register */
        val = it8709_rr(dev, IT85_C0RCR)
                & ~(IT85_RXEND | IT85_RXDCR);

        if (use_demodulator)
                val |= IT85_RXEND;

        val |= allowance_bits;

        it8709_wr(dev, val, IT85_C0RCR);

        /* program the C0TCR register */
        val = it8709_rr(dev, IT85_C0TCR) & ~IT85_TXMPW;
        val |= pulse_width_bits;
        it8709_wr(dev, val, IT85_C0TCR);
}

/* read up to buf_size bytes from the RX FIFO; to be called with the spinlock
 * held */
static int it8709_get_rx_bytes(struct ite_dev *dev, u8 * buf, int buf_size)
{
        int fifo, read = 0;

        ite_dbg("%s called", __func__);

        /* read how many bytes are still in the FIFO */
        fifo = it8709_rm(dev, IT8709_RFSR) & IT85_RXFBC;

        while (fifo > 0 && buf_size > 0) {
                *(buf++) = it8709_rm(dev, IT8709_FIFO + read);
                fifo--;
                read++;
                buf_size--;
        }

        /* 'clear' the FIFO by setting the writing index to 0; this is
         * completely bound to be racy, but we can't help it, since it's a
         * limitation of the protocol */
        it8709_wm(dev, 0, IT8709_RFSR);

        return read;
}

/* return how many bytes are still in the FIFO; this will be called
 * with the device spinlock NOT HELD while waiting for the TX FIFO to get
 * empty; let's expect this won't be a problem */
static int it8709_get_tx_used_slots(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        return it8709_rr(dev, IT85_C0TFSR) & IT85_TXFBC;
}

/* put a byte to the TX fifo; this should be called with the spinlock held */
static void it8709_put_tx_byte(struct ite_dev *dev, u8 value)
{
        it8709_wr(dev, value, IT85_C0DR);
}

/* idle the receiver so that we won't receive samples until another
  pulse is detected; this must be called with the device spinlock held */
static void it8709_idle_rx(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* disable streaming by clearing RXACT writing it as 1 */
        it8709_wr(dev, it8709_rr(dev, IT85_C0RCR) | IT85_RXACT,
                            IT85_C0RCR);

        /* clear the FIFO */
        it8709_wr(dev, it8709_rr(dev, IT85_C0MSTCR) | IT85_FIFOCLR,
                            IT85_C0MSTCR);
}

/* disable the receiver; this must be called with the device spinlock held */
static void it8709_disable_rx(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* disable the receiver interrupts */
        it8709_wr(dev, it8709_rr(dev, IT85_C0IER) &
                            ~(IT85_RDAIE | IT85_RFOIE),
                            IT85_C0IER);

        /* disable the receiver */
        it8709_wr(dev, it8709_rr(dev, IT85_C0RCR) & ~IT85_RXEN,
                            IT85_C0RCR);

        /* clear the FIFO and RXACT (actually RXACT should have been cleared
         * in the previous it8709_wr(dev, ) call) */
        it8709_idle_rx(dev);
}

/* enable the receiver; this must be called with the device spinlock held */
static void it8709_enable_rx(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* enable the receiver by setting RXEN */
        it8709_wr(dev, it8709_rr(dev, IT85_C0RCR) | IT85_RXEN,
                            IT85_C0RCR);

        /* just prepare it to idle for the next reception */
        it8709_idle_rx(dev);

        /* enable the receiver interrupts and master enable flag */
        it8709_wr(dev, it8709_rr(dev, IT85_C0IER)
                            |IT85_RDAIE | IT85_RFOIE | IT85_IEC,
                            IT85_C0IER);
}

/* disable the transmitter interrupt; this must be called with the device
 * spinlock held */
static void it8709_disable_tx_interrupt(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* disable the transmitter interrupts */
        it8709_wr(dev, it8709_rr(dev, IT85_C0IER) & ~IT85_TLDLIE,
                            IT85_C0IER);
}

/* enable the transmitter interrupt; this must be called with the device
 * spinlock held */
static void it8709_enable_tx_interrupt(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* enable the transmitter interrupts and master enable flag */
        it8709_wr(dev, it8709_rr(dev, IT85_C0IER)
                            |IT85_TLDLIE | IT85_IEC,
                            IT85_C0IER);
}

/* disable the device; this must be called with the device spinlock held */
static void it8709_disable(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* clear out all interrupt enable flags */
        it8709_wr(dev, it8709_rr(dev, IT85_C0IER) &
                        ~(IT85_IEC | IT85_RFOIE | IT85_RDAIE | IT85_TLDLIE),
                  IT85_C0IER);

        /* disable the receiver */
        it8709_disable_rx(dev);

        /* erase the FIFO */
        it8709_wr(dev, IT85_FIFOCLR | it8709_rr(dev, IT85_C0MSTCR),
                            IT85_C0MSTCR);
}

/* initialize the hardware */
static void it8709_init_hardware(struct ite_dev *dev)
{
        ite_dbg("%s called", __func__);

        /* disable all the interrupts */
        it8709_wr(dev, it8709_rr(dev, IT85_C0IER) &
                        ~(IT85_IEC | IT85_RFOIE | IT85_RDAIE | IT85_TLDLIE),
                  IT85_C0IER);

        /* program the baud rate divisor */
        it8709_wr(dev, ITE_BAUDRATE_DIVISOR & 0xff, IT85_C0BDLR);
        it8709_wr(dev, (ITE_BAUDRATE_DIVISOR >> 8) & 0xff,
                        IT85_C0BDHR);

        /* program the C0MSTCR register defaults */
        it8709_wr(dev, (it8709_rr(dev, IT85_C0MSTCR) &
                        ~(IT85_ILSEL | IT85_ILE | IT85_FIFOTL
                          | IT85_FIFOCLR | IT85_RESET)) | IT85_FIFOTL_DEFAULT,
                  IT85_C0MSTCR);

        /* program the C0RCR register defaults */
        it8709_wr(dev, (it8709_rr(dev, IT85_C0RCR) &
                        ~(IT85_RXEN | IT85_RDWOS | IT85_RXEND | IT85_RXACT
                          | IT85_RXDCR)) | ITE_RXDCR_DEFAULT,
                  IT85_C0RCR);

        /* program the C0TCR register defaults */
        it8709_wr(dev, (it8709_rr(dev, IT85_C0TCR) & ~(IT85_TXMPM | IT85_TXMPW))
                        | IT85_TXRLE | IT85_TXENDF | IT85_TXMPM_DEFAULT
                        | IT85_TXMPW_DEFAULT,
                  IT85_C0TCR);

        /* program the carrier parameters */
        ite_set_carrier_params(dev);
}


/* generic hardware setup/teardown code */

/* activate the device for use */
static int ite_open(struct rc_dev *rcdev)
{
        struct ite_dev *dev = rcdev->priv;
        unsigned long flags;

        ite_dbg("%s called", __func__);

        spin_lock_irqsave(&dev->lock, flags);
        dev->in_use = true;

        /* enable the receiver */
        dev->params.enable_rx(dev);

        spin_unlock_irqrestore(&dev->lock, flags);

        return 0;
}

/* deactivate the device for use */
static void ite_close(struct rc_dev *rcdev)
{
        struct ite_dev *dev = rcdev->priv;
        unsigned long flags;

        ite_dbg("%s called", __func__);

        spin_lock_irqsave(&dev->lock, flags);
        dev->in_use = false;

        /* wait for any transmission to end */
        spin_unlock_irqrestore(&dev->lock, flags);
        wait_event_interruptible(dev->tx_ended, !dev->transmitting);
        spin_lock_irqsave(&dev->lock, flags);

        dev->params.disable(dev);

        spin_unlock_irqrestore(&dev->lock, flags);
}

/* supported models and their parameters */
static const struct ite_dev_params ite_dev_descs[] = {
        {       /* 0: ITE8704 */
               .model = "ITE8704 CIR transceiver",
               .io_region_size = IT87_IOREG_LENGTH,
               .io_rsrc_no = 0,
               .hw_tx_capable = true,
               .sample_period = (u32) (1000000000ULL / 115200),
               .tx_carrier_freq = 38000,
               .tx_duty_cycle = 33,
               .rx_low_carrier_freq = 0,
               .rx_high_carrier_freq = 0,

                /* operations */
               .get_irq_causes = it87_get_irq_causes,
               .enable_rx = it87_enable_rx,
               .idle_rx = it87_idle_rx,
               .disable_rx = it87_idle_rx,
               .get_rx_bytes = it87_get_rx_bytes,
               .enable_tx_interrupt = it87_enable_tx_interrupt,
               .disable_tx_interrupt = it87_disable_tx_interrupt,
               .get_tx_used_slots = it87_get_tx_used_slots,
               .put_tx_byte = it87_put_tx_byte,
               .disable = it87_disable,
               .init_hardware = it87_init_hardware,
               .set_carrier_params = it87_set_carrier_params,
               },
        {       /* 1: ITE8713 */
               .model = "ITE8713 CIR transceiver",
               .io_region_size = IT87_IOREG_LENGTH,
               .io_rsrc_no = 0,
               .hw_tx_capable = true,
               .sample_period = (u32) (1000000000ULL / 115200),
               .tx_carrier_freq = 38000,
               .tx_duty_cycle = 33,
               .rx_low_carrier_freq = 0,
               .rx_high_carrier_freq = 0,

                /* operations */
               .get_irq_causes = it87_get_irq_causes,
               .enable_rx = it87_enable_rx,
               .idle_rx = it87_idle_rx,
               .disable_rx = it87_idle_rx,
               .get_rx_bytes = it87_get_rx_bytes,
               .enable_tx_interrupt = it87_enable_tx_interrupt,
               .disable_tx_interrupt = it87_disable_tx_interrupt,
               .get_tx_used_slots = it87_get_tx_used_slots,
               .put_tx_byte = it87_put_tx_byte,
               .disable = it87_disable,
               .init_hardware = it87_init_hardware,
               .set_carrier_params = it87_set_carrier_params,
               },
        {       /* 2: ITE8708 */
               .model = "ITE8708 CIR transceiver",
               .io_region_size = IT8708_IOREG_LENGTH,
               .io_rsrc_no = 0,
               .hw_tx_capable = true,
               .sample_period = (u32) (1000000000ULL / 115200),
               .tx_carrier_freq = 38000,
               .tx_duty_cycle = 33,
               .rx_low_carrier_freq = 0,
               .rx_high_carrier_freq = 0,

                /* operations */
               .get_irq_causes = it8708_get_irq_causes,
               .enable_rx = it8708_enable_rx,
               .idle_rx = it8708_idle_rx,
               .disable_rx = it8708_idle_rx,
               .get_rx_bytes = it8708_get_rx_bytes,
               .enable_tx_interrupt = it8708_enable_tx_interrupt,
               .disable_tx_interrupt =
               it8708_disable_tx_interrupt,
               .get_tx_used_slots = it8708_get_tx_used_slots,
               .put_tx_byte = it8708_put_tx_byte,
               .disable = it8708_disable,
               .init_hardware = it8708_init_hardware,
               .set_carrier_params = it8708_set_carrier_params,
               },
        {       /* 3: ITE8709 */
               .model = "ITE8709 CIR transceiver",
               .io_region_size = IT8709_IOREG_LENGTH,
               .io_rsrc_no = 2,
               .hw_tx_capable = true,
               .sample_period = (u32) (1000000000ULL / 115200),
               .tx_carrier_freq = 38000,
               .tx_duty_cycle = 33,
               .rx_low_carrier_freq = 0,
               .rx_high_carrier_freq = 0,

                /* operations */
               .get_irq_causes = it8709_get_irq_causes,
               .enable_rx = it8709_enable_rx,
               .idle_rx = it8709_idle_rx,
               .disable_rx = it8709_idle_rx,
               .get_rx_bytes = it8709_get_rx_bytes,
               .enable_tx_interrupt = it8709_enable_tx_interrupt,
               .disable_tx_interrupt =
               it8709_disable_tx_interrupt,
               .get_tx_used_slots = it8709_get_tx_used_slots,
               .put_tx_byte = it8709_put_tx_byte,
               .disable = it8709_disable,
               .init_hardware = it8709_init_hardware,
               .set_carrier_params = it8709_set_carrier_params,
               },
};

static const struct pnp_device_id ite_ids[] = {
        {"ITE8704", 0},         /* Default model */
        {"ITE8713", 1},         /* CIR found in EEEBox 1501U */
        {"ITE8708", 2},         /* Bridged IT8512 */
        {"ITE8709", 3},         /* SRAM-Bridged IT8512 */
        {"", 0},
};

/* allocate memory, probe hardware, and initialize everything */
static int ite_probe(struct pnp_dev *pdev, const struct pnp_device_id
                     *dev_id)
{
        const struct ite_dev_params *dev_desc = NULL;
        struct ite_dev *itdev = NULL;
        struct rc_dev *rdev = NULL;
        int ret = -ENOMEM;
        int model_no;
        int io_rsrc_no;

        ite_dbg("%s called", __func__);

        itdev = kzalloc(sizeof(struct ite_dev), GFP_KERNEL);
        if (!itdev)
                return ret;

        /* input device for IR remote (and tx) */
        rdev = rc_allocate_device(RC_DRIVER_IR_RAW);
        if (!rdev)
                goto exit_free_dev_rdev;
        itdev->rdev = rdev;

        ret = -ENODEV;

        /* get the model number */
        model_no = (int)dev_id->driver_data;
        ite_pr(KERN_NOTICE, "Auto-detected model: %s\n",
                ite_dev_descs[model_no].model);

        if (model_number >= 0 && model_number < ARRAY_SIZE(ite_dev_descs)) {
                model_no = model_number;
                ite_pr(KERN_NOTICE, "The model has been fixed by a module parameter.");
        }

        ite_pr(KERN_NOTICE, "Using model: %s\n", ite_dev_descs[model_no].model);

        /* get the description for the device */
        dev_desc = &ite_dev_descs[model_no];
        io_rsrc_no = dev_desc->io_rsrc_no;

        /* validate pnp resources */
        if (!pnp_port_valid(pdev, io_rsrc_no) ||
            pnp_port_len(pdev, io_rsrc_no) != dev_desc->io_region_size) {
                dev_err(&pdev->dev, "IR PNP Port not valid!\n");
                goto exit_free_dev_rdev;
        }

        if (!pnp_irq_valid(pdev, 0)) {
                dev_err(&pdev->dev, "PNP IRQ not valid!\n");
                goto exit_free_dev_rdev;
        }

        /* store resource values */
        itdev->cir_addr = pnp_port_start(pdev, io_rsrc_no);
        itdev->cir_irq = pnp_irq(pdev, 0);

        /* initialize spinlocks */
        spin_lock_init(&itdev->lock);

        /* set driver data into the pnp device */
        pnp_set_drvdata(pdev, itdev);
        itdev->pdev = pdev;

        /* initialize waitqueues for transmission */
        init_waitqueue_head(&itdev->tx_queue);
        init_waitqueue_head(&itdev->tx_ended);

        /* copy model-specific parameters */
        itdev->params = *dev_desc;

        /* apply any overrides */
        if (sample_period > 0)
                itdev->params.sample_period = sample_period;

        if (tx_carrier_freq > 0)
                itdev->params.tx_carrier_freq = tx_carrier_freq;

        if (tx_duty_cycle > 0 && tx_duty_cycle <= 100)
                itdev->params.tx_duty_cycle = tx_duty_cycle;

        if (rx_low_carrier_freq > 0)
                itdev->params.rx_low_carrier_freq = rx_low_carrier_freq;

        if (rx_high_carrier_freq > 0)
                itdev->params.rx_high_carrier_freq = rx_high_carrier_freq;

        /* print out parameters */
        ite_pr(KERN_NOTICE, "TX-capable: %d\n", (int)
                         itdev->params.hw_tx_capable);
        ite_pr(KERN_NOTICE, "Sample period (ns): %ld\n", (long)
                     itdev->params.sample_period);
        ite_pr(KERN_NOTICE, "TX carrier frequency (Hz): %d\n", (int)
                     itdev->params.tx_carrier_freq);
        ite_pr(KERN_NOTICE, "TX duty cycle (%%): %d\n", (int)
                     itdev->params.tx_duty_cycle);
        ite_pr(KERN_NOTICE, "RX low carrier frequency (Hz): %d\n", (int)
                     itdev->params.rx_low_carrier_freq);
        ite_pr(KERN_NOTICE, "RX high carrier frequency (Hz): %d\n", (int)
                     itdev->params.rx_high_carrier_freq);

        /* set up hardware initial state */
        itdev->params.init_hardware(itdev);

        /* set up ir-core props */
        rdev->priv = itdev;
        rdev->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
        rdev->open = ite_open;
        rdev->close = ite_close;
        rdev->s_idle = ite_s_idle;
        rdev->s_rx_carrier_range = ite_set_rx_carrier_range;
        /* FIFO threshold is 17 bytes, so 17 * 8 samples minimum */
        rdev->min_timeout = 17 * 8 * ITE_BAUDRATE_DIVISOR *
                            itdev->params.sample_period;
        rdev->timeout = IR_DEFAULT_TIMEOUT;
        rdev->max_timeout = 10 * IR_DEFAULT_TIMEOUT;
        rdev->rx_resolution = ITE_BAUDRATE_DIVISOR *
                                itdev->params.sample_period;
        rdev->tx_resolution = ITE_BAUDRATE_DIVISOR *
                                itdev->params.sample_period;

        /* set up transmitter related values if needed */
        if (itdev->params.hw_tx_capable) {
                rdev->tx_ir = ite_tx_ir;
                rdev->s_tx_carrier = ite_set_tx_carrier;
                rdev->s_tx_duty_cycle = ite_set_tx_duty_cycle;
        }

        rdev->device_name = dev_desc->model;
        rdev->input_id.bustype = BUS_HOST;
        rdev->input_id.vendor = PCI_VENDOR_ID_ITE;
        rdev->input_id.product = 0;
        rdev->input_id.version = 0;
        rdev->driver_name = ITE_DRIVER_NAME;
        rdev->map_name = RC_MAP_RC6_MCE;

        ret = rc_register_device(rdev);
        if (ret)
                goto exit_free_dev_rdev;

        ret = -EBUSY;
        /* now claim resources */
        if (!request_region(itdev->cir_addr,
                                dev_desc->io_region_size, ITE_DRIVER_NAME))
                goto exit_unregister_device;

        if (request_irq(itdev->cir_irq, ite_cir_isr, IRQF_SHARED,
                        ITE_DRIVER_NAME, (void *)itdev))
                goto exit_release_cir_addr;

        ite_pr(KERN_NOTICE, "driver has been successfully loaded\n");

        return 0;

exit_release_cir_addr:
        release_region(itdev->cir_addr, itdev->params.io_region_size);
exit_unregister_device:
        rc_unregister_device(rdev);
        rdev = NULL;
exit_free_dev_rdev:
        rc_free_device(rdev);
        kfree(itdev);

        return ret;
}

static void ite_remove(struct pnp_dev *pdev)
{
        struct ite_dev *dev = pnp_get_drvdata(pdev);
        unsigned long flags;

        ite_dbg("%s called", __func__);

        spin_lock_irqsave(&dev->lock, flags);

        /* disable hardware */
        dev->params.disable(dev);

        spin_unlock_irqrestore(&dev->lock, flags);

        /* free resources */
        free_irq(dev->cir_irq, dev);
        release_region(dev->cir_addr, dev->params.io_region_size);

        rc_unregister_device(dev->rdev);

        kfree(dev);
}

static int ite_suspend(struct pnp_dev *pdev, pm_message_t state)
{
        struct ite_dev *dev = pnp_get_drvdata(pdev);
        unsigned long flags;

        ite_dbg("%s called", __func__);

        /* wait for any transmission to end */
        wait_event_interruptible(dev->tx_ended, !dev->transmitting);

        spin_lock_irqsave(&dev->lock, flags);

        /* disable all interrupts */
        dev->params.disable(dev);

        spin_unlock_irqrestore(&dev->lock, flags);

        return 0;
}

static int ite_resume(struct pnp_dev *pdev)
{
        struct ite_dev *dev = pnp_get_drvdata(pdev);
        unsigned long flags;

        ite_dbg("%s called", __func__);

        spin_lock_irqsave(&dev->lock, flags);

        /* reinitialize hardware config registers */
        dev->params.init_hardware(dev);
        /* enable the receiver */
        dev->params.enable_rx(dev);

        spin_unlock_irqrestore(&dev->lock, flags);

        return 0;
}

static void ite_shutdown(struct pnp_dev *pdev)
{
        struct ite_dev *dev = pnp_get_drvdata(pdev);
        unsigned long flags;

        ite_dbg("%s called", __func__);

        spin_lock_irqsave(&dev->lock, flags);

        /* disable all interrupts */
        dev->params.disable(dev);

        spin_unlock_irqrestore(&dev->lock, flags);
}

static struct pnp_driver ite_driver = {
        .name           = ITE_DRIVER_NAME,
        .id_table       = ite_ids,
        .probe          = ite_probe,
        .remove         = ite_remove,
        .suspend        = ite_suspend,
        .resume         = ite_resume,
        .shutdown       = ite_shutdown,
};

MODULE_DEVICE_TABLE(pnp, ite_ids);
MODULE_DESCRIPTION("ITE Tech Inc. IT8712F/ITE8512F CIR driver");

MODULE_AUTHOR("Juan J. Garcia de Soria <skandalfo@gmail.com>");
MODULE_LICENSE("GPL");

module_pnp_driver(ite_driver);