/*
 *  USB ATI Remote support
 *
 *                Copyright (c) 2011, 2012 Anssi Hannula <anssi.hannula@iki.fi>
 *  Version 2.2.0 Copyright (c) 2004 Torrey Hoffman <thoffman@arnor.net>
 *  Version 2.1.1 Copyright (c) 2002 Vladimir Dergachev
 *
 *  This 2.2.0 version is a rewrite / cleanup of the 2.1.1 driver, including
 *  porting to the 2.6 kernel interfaces, along with other modification
 *  to better match the style of the existing usb/input drivers.  However, the
 *  protocol and hardware handling is essentially unchanged from 2.1.1.
 *
 *  The 2.1.1 driver was derived from the usbati_remote and usbkbd drivers by
 *  Vojtech Pavlik.
 *
 *  Changes:
 *
 *  Feb 2004: Torrey Hoffman <thoffman@arnor.net>
 *            Version 2.2.0
 *  Jun 2004: Torrey Hoffman <thoffman@arnor.net>
 *            Version 2.2.1
 *            Added key repeat support contributed by:
 *                Vincent Vanackere <vanackere@lif.univ-mrs.fr>
 *            Added support for the "Lola" remote contributed by:
 *                Seth Cohn <sethcohn@yahoo.com>
 *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 *
 * Hardware & software notes
 *
 * These remote controls are distributed by ATI as part of their
 * "All-In-Wonder" video card packages.  The receiver self-identifies as a
 * "USB Receiver" with manufacturer "X10 Wireless Technology Inc".
 *
 * The "Lola" remote is available from X10.  See:
 *    http://www.x10.com/products/lola_sg1.htm
 * The Lola is similar to the ATI remote but has no mouse support, and slightly
 * different keys.
 *
 * It is possible to use multiple receivers and remotes on multiple computers
 * simultaneously by configuring them to use specific channels.
 *
 * The RF protocol used by the remote supports 16 distinct channels, 1 to 16.
 * Actually, it may even support more, at least in some revisions of the
 * hardware.
 *
 * Each remote can be configured to transmit on one channel as follows:
 *   - Press and hold the "hand icon" button.
 *   - When the red LED starts to blink, let go of the "hand icon" button.
 *   - When it stops blinking, input the channel code as two digits, from 01
 *     to 16, and press the hand icon again.
 *
 * The timing can be a little tricky.  Try loading the module with debug=1
 * to have the kernel print out messages about the remote control number
 * and mask.  Note: debugging prints remote numbers as zero-based hexadecimal.
 *
 * The driver has a "channel_mask" parameter. This bitmask specifies which
 * channels will be ignored by the module.  To mask out channels, just add
 * all the 2^channel_number values together.
 *
 * For instance, set channel_mask = 2^4 = 16 (binary 10000) to make ati_remote
 * ignore signals coming from remote controls transmitting on channel 4, but
 * accept all other channels.
 *
 * Or, set channel_mask = 65533, (0xFFFD), and all channels except 1 will be
 * ignored.
 *
 * The default is 0 (respond to all channels). Bit 0 and bits 17-32 of this
 * parameter are unused.
 *
 */

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/usb/input.h>
#include <linux/wait.h>
#include <linux/jiffies.h>
#include <media/rc-core.h>

/*
 * Module and Version Information, Module Parameters
 */

#define ATI_REMOTE_VENDOR_ID            0x0bc7
#define LOLA_REMOTE_PRODUCT_ID          0x0002
#define LOLA2_REMOTE_PRODUCT_ID         0x0003
#define ATI_REMOTE_PRODUCT_ID           0x0004
#define NVIDIA_REMOTE_PRODUCT_ID        0x0005
#define MEDION_REMOTE_PRODUCT_ID        0x0006
#define FIREFLY_REMOTE_PRODUCT_ID       0x0008

#define DRIVER_VERSION          "2.2.1"
#define DRIVER_AUTHOR           "Torrey Hoffman <thoffman@arnor.net>"
#define DRIVER_DESC             "ATI/X10 RF USB Remote Control"

#define NAME_BUFSIZE      80    /* size of product name, path buffers */
#define DATA_BUFSIZE      63    /* size of URB data buffers */

/*
 * Duplicate event filtering time.
 * Sequential, identical KIND_FILTERED inputs with less than
 * FILTER_TIME milliseconds between them are considered as repeat
 * events. The hardware generates 5 events for the first keypress
 * and we have to take this into account for an accurate repeat
 * behaviour.
 */
#define FILTER_TIME     60 /* msec */
#define REPEAT_DELAY    500 /* msec */

static unsigned long channel_mask;
module_param(channel_mask, ulong, 0644);
MODULE_PARM_DESC(channel_mask, "Bitmask of remote control channels to ignore");

static int debug;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "Enable extra debug messages and information");

static int repeat_filter = FILTER_TIME;
module_param(repeat_filter, int, 0644);
MODULE_PARM_DESC(repeat_filter, "Repeat filter time, default = 60 msec");

static int repeat_delay = REPEAT_DELAY;
module_param(repeat_delay, int, 0644);
MODULE_PARM_DESC(repeat_delay, "Delay before sending repeats, default = 500 msec");

static bool mouse = true;
module_param(mouse, bool, 0444);
MODULE_PARM_DESC(mouse, "Enable mouse device, default = yes");

#define dbginfo(dev, format, arg...) \
        do { if (debug) dev_info(dev , format , ## arg); } while (0)
#undef err
#define err(format, arg...) printk(KERN_ERR format , ## arg)

struct ati_receiver_type {
        /* either default_keymap or get_default_keymap should be set */
        const char *default_keymap;
        const char *(*get_default_keymap)(struct usb_interface *interface);
};

static const char *get_medion_keymap(struct usb_interface *interface)
{
        struct usb_device *udev = interface_to_usbdev(interface);

        /*
         * There are many different Medion remotes shipped with a receiver
         * with the same usb id, but the receivers have subtle differences
         * in the USB descriptors allowing us to detect them.
         */

        if (udev->manufacturer && udev->product) {
                if (udev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_WAKEUP) {

                        if (!strcmp(udev->manufacturer, "X10 Wireless Technology Inc")
                            && !strcmp(udev->product, "USB Receiver"))
                                return RC_MAP_MEDION_X10_DIGITAINER;

                        if (!strcmp(udev->manufacturer, "X10 WTI")
                            && !strcmp(udev->product, "RF receiver"))
                                return RC_MAP_MEDION_X10_OR2X;
                } else {

                         if (!strcmp(udev->manufacturer, "X10 Wireless Technology Inc")
                            && !strcmp(udev->product, "USB Receiver"))
                                return RC_MAP_MEDION_X10;
                }
        }

        dev_info(&interface->dev,
                 "Unknown Medion X10 receiver, using default ati_remote Medion keymap\n");

        return RC_MAP_MEDION_X10;
}

static const struct ati_receiver_type type_ati          = {
        .default_keymap = RC_MAP_ATI_X10
};
static const struct ati_receiver_type type_medion       = {
        .get_default_keymap = get_medion_keymap
};
static const struct ati_receiver_type type_firefly      = {
        .default_keymap = RC_MAP_SNAPSTREAM_FIREFLY
};

static struct usb_device_id ati_remote_table[] = {
        {
                USB_DEVICE(ATI_REMOTE_VENDOR_ID, LOLA_REMOTE_PRODUCT_ID),
                .driver_info = (unsigned long)&type_ati
        },
        {
                USB_DEVICE(ATI_REMOTE_VENDOR_ID, LOLA2_REMOTE_PRODUCT_ID),
                .driver_info = (unsigned long)&type_ati
        },
        {
                USB_DEVICE(ATI_REMOTE_VENDOR_ID, ATI_REMOTE_PRODUCT_ID),
                .driver_info = (unsigned long)&type_ati
        },
        {
                USB_DEVICE(ATI_REMOTE_VENDOR_ID, NVIDIA_REMOTE_PRODUCT_ID),
                .driver_info = (unsigned long)&type_ati
        },
        {
                USB_DEVICE(ATI_REMOTE_VENDOR_ID, MEDION_REMOTE_PRODUCT_ID),
                .driver_info = (unsigned long)&type_medion
        },
        {
                USB_DEVICE(ATI_REMOTE_VENDOR_ID, FIREFLY_REMOTE_PRODUCT_ID),
                .driver_info = (unsigned long)&type_firefly
        },
        {}      /* Terminating entry */
};

MODULE_DEVICE_TABLE(usb, ati_remote_table);

/* Get hi and low bytes of a 16-bits int */
#define HI(a)   ((unsigned char)((a) >> 8))
#define LO(a)   ((unsigned char)((a) & 0xff))

#define SEND_FLAG_IN_PROGRESS   1
#define SEND_FLAG_COMPLETE      2

/* Device initialization strings */
static char init1[] = { 0x01, 0x00, 0x20, 0x14 };
static char init2[] = { 0x01, 0x00, 0x20, 0x14, 0x20, 0x20, 0x20 };

struct ati_remote {
        struct input_dev *idev;
        struct rc_dev *rdev;
        struct usb_device *udev;
        struct usb_interface *interface;

        struct urb *irq_urb;
        struct urb *out_urb;
        struct usb_endpoint_descriptor *endpoint_in;
        struct usb_endpoint_descriptor *endpoint_out;
        unsigned char *inbuf;
        unsigned char *outbuf;
        dma_addr_t inbuf_dma;
        dma_addr_t outbuf_dma;

        unsigned char old_data;     /* Detect duplicate events */
        unsigned long old_jiffies;
        unsigned long acc_jiffies;  /* handle acceleration */
        unsigned long first_jiffies;

        unsigned int repeat_count;

        char rc_name[NAME_BUFSIZE];
        char rc_phys[NAME_BUFSIZE];
        char mouse_name[NAME_BUFSIZE];
        char mouse_phys[NAME_BUFSIZE];

        wait_queue_head_t wait;
        int send_flags;

        int users; /* 0-2, users are rc and input */
        struct mutex open_mutex;
};

/* "Kinds" of messages sent from the hardware to the driver. */
#define KIND_END        0
#define KIND_LITERAL    1   /* Simply pass to input system as EV_KEY */
#define KIND_FILTERED   2   /* Add artificial key-up events, drop keyrepeats */
#define KIND_ACCEL      3   /* Translate to EV_REL mouse-move events */

/* Translation table from hardware messages to input events. */
static const struct {
        unsigned char kind;
        unsigned char data;     /* Raw key code from remote */
        unsigned short code;    /* Input layer translation */
}  ati_remote_tbl[] = {
        /* Directional control pad axes.  Code is xxyy */
        {KIND_ACCEL,    0x70, 0xff00},  /* left */
        {KIND_ACCEL,    0x71, 0x0100},  /* right */
        {KIND_ACCEL,    0x72, 0x00ff},  /* up */
        {KIND_ACCEL,    0x73, 0x0001},  /* down */

        /* Directional control pad diagonals */
        {KIND_ACCEL,    0x74, 0xffff},  /* left up */
        {KIND_ACCEL,    0x75, 0x01ff},  /* right up */
        {KIND_ACCEL,    0x77, 0xff01},  /* left down */
        {KIND_ACCEL,    0x76, 0x0101},  /* right down */

        /* "Mouse button" buttons.  The code below uses the fact that the
         * lsbit of the raw code is a down/up indicator. */
        {KIND_LITERAL,  0x78, BTN_LEFT}, /* left btn down */
        {KIND_LITERAL,  0x79, BTN_LEFT}, /* left btn up */
        {KIND_LITERAL,  0x7c, BTN_RIGHT},/* right btn down */
        {KIND_LITERAL,  0x7d, BTN_RIGHT},/* right btn up */

        /* Artificial "doubleclick" events are generated by the hardware.
         * They are mapped to the "side" and "extra" mouse buttons here. */
        {KIND_FILTERED, 0x7a, BTN_SIDE}, /* left dblclick */
        {KIND_FILTERED, 0x7e, BTN_EXTRA},/* right dblclick */

        /* Non-mouse events are handled by rc-core */
        {KIND_END, 0x00, 0}
};

/*
 * ati_remote_dump_input
 */
static void ati_remote_dump(struct device *dev, unsigned char *data,
                            unsigned int len)
{
        if (len == 1) {
                if (data[0] != (unsigned char)0xff && data[0] != 0x00)
                        dev_warn(dev, "Weird byte 0x%02x\n", data[0]);
        } else if (len == 4)
                dev_warn(dev, "Weird key %*ph\n", 4, data);
        else
                dev_warn(dev, "Weird data, len=%d %*ph ...\n", len, 6, data);
}

/*
 * ati_remote_open
 */
static int ati_remote_open(struct ati_remote *ati_remote)
{
        int err = 0;

        mutex_lock(&ati_remote->open_mutex);

        if (ati_remote->users++ != 0)
                goto out; /* one was already active */

        /* On first open, submit the read urb which was set up previously. */
        ati_remote->irq_urb->dev = ati_remote->udev;
        if (usb_submit_urb(ati_remote->irq_urb, GFP_KERNEL)) {
                dev_err(&ati_remote->interface->dev,
                        "%s: usb_submit_urb failed!\n", __func__);
                err = -EIO;
        }

out:    mutex_unlock(&ati_remote->open_mutex);
        return err;
}

/*
 * ati_remote_close
 */
static void ati_remote_close(struct ati_remote *ati_remote)
{
        mutex_lock(&ati_remote->open_mutex);
        if (--ati_remote->users == 0)
                usb_kill_urb(ati_remote->irq_urb);
        mutex_unlock(&ati_remote->open_mutex);
}

static int ati_remote_input_open(struct input_dev *inputdev)
{
        struct ati_remote *ati_remote = input_get_drvdata(inputdev);
        return ati_remote_open(ati_remote);
}

static void ati_remote_input_close(struct input_dev *inputdev)
{
        struct ati_remote *ati_remote = input_get_drvdata(inputdev);
        ati_remote_close(ati_remote);
}

static int ati_remote_rc_open(struct rc_dev *rdev)
{
        struct ati_remote *ati_remote = rdev->priv;
        return ati_remote_open(ati_remote);
}

static void ati_remote_rc_close(struct rc_dev *rdev)
{
        struct ati_remote *ati_remote = rdev->priv;
        ati_remote_close(ati_remote);
}

/*
 * ati_remote_irq_out
 */
static void ati_remote_irq_out(struct urb *urb)
{
        struct ati_remote *ati_remote = urb->context;

        if (urb->status) {
                dev_dbg(&ati_remote->interface->dev, "%s: status %d\n",
                        __func__, urb->status);
                return;
        }

        ati_remote->send_flags |= SEND_FLAG_COMPLETE;
        wmb();
        wake_up(&ati_remote->wait);
}

/*
 * ati_remote_sendpacket
 *
 * Used to send device initialization strings
 */
static int ati_remote_sendpacket(struct ati_remote *ati_remote, u16 cmd,
        unsigned char *data)
{
        int retval = 0;

        /* Set up out_urb */
        memcpy(ati_remote->out_urb->transfer_buffer + 1, data, LO(cmd));
        ((char *) ati_remote->out_urb->transfer_buffer)[0] = HI(cmd);

        ati_remote->out_urb->transfer_buffer_length = LO(cmd) + 1;
        ati_remote->out_urb->dev = ati_remote->udev;
        ati_remote->send_flags = SEND_FLAG_IN_PROGRESS;

        retval = usb_submit_urb(ati_remote->out_urb, GFP_ATOMIC);
        if (retval) {
                dev_dbg(&ati_remote->interface->dev,
                         "sendpacket: usb_submit_urb failed: %d\n", retval);
                return retval;
        }

        wait_event_timeout(ati_remote->wait,
                ((ati_remote->out_urb->status != -EINPROGRESS) ||
                        (ati_remote->send_flags & SEND_FLAG_COMPLETE)),
                HZ);
        usb_kill_urb(ati_remote->out_urb);

        return retval;
}

struct accel_times {
        const char      value;
        unsigned int    msecs;
};

static const struct accel_times accel[] = {
        {  1,  125 },
        {  2,  250 },
        {  4,  500 },
        {  6, 1000 },
        {  9, 1500 },
        { 13, 2000 },
        { 20,    0 },
};

/*
 * ati_remote_compute_accel
 *
 * Implements acceleration curve for directional control pad
 * If elapsed time since last event is > 1/4 second, user "stopped",
 * so reset acceleration. Otherwise, user is probably holding the control
 * pad down, so we increase acceleration, ramping up over two seconds to
 * a maximum speed.
 */
static int ati_remote_compute_accel(struct ati_remote *ati_remote)
{
        unsigned long now = jiffies, reset_time;
        int i;

        reset_time = msecs_to_jiffies(250);

        if (time_after(now, ati_remote->old_jiffies + reset_time)) {
                ati_remote->acc_jiffies = now;
                return 1;
        }
        for (i = 0; i < ARRAY_SIZE(accel) - 1; i++) {
                unsigned long timeout = msecs_to_jiffies(accel[i].msecs);

                if (time_before(now, ati_remote->acc_jiffies + timeout))
                        return accel[i].value;
        }
        return accel[i].value;
}

/*
 * ati_remote_report_input
 */
static void ati_remote_input_report(struct urb *urb)
{
        struct ati_remote *ati_remote = urb->context;
        unsigned char *data= ati_remote->inbuf;
        struct input_dev *dev = ati_remote->idev;
        int index = -1;
        int remote_num;
        unsigned char scancode;
        u32 wheel_keycode = KEY_RESERVED;
        int i;

        /*
         * data[0] = 0x14
         * data[1] = data[2] + data[3] + 0xd5 (a checksum byte)
         * data[2] = the key code (with toggle bit in MSB with some models)
         * data[3] = channel << 4 (the low 4 bits must be zero)
         */

        /* Deal with strange looking inputs */
        if ( urb->actual_length != 4 || data[0] != 0x14 ||
             data[1] != (unsigned char)(data[2] + data[3] + 0xD5) ||
             (data[3] & 0x0f) != 0x00) {
                ati_remote_dump(&urb->dev->dev, data, urb->actual_length);
                return;
        }

        if (data[1] != ((data[2] + data[3] + 0xd5) & 0xff)) {
                dbginfo(&ati_remote->interface->dev,
                        "wrong checksum in input: %*ph\n", 4, data);
                return;
        }

        /* Mask unwanted remote channels.  */
        /* note: remote_num is 0-based, channel 1 on remote == 0 here */
        remote_num = (data[3] >> 4) & 0x0f;
        if (channel_mask & (1 << (remote_num + 1))) {
                dbginfo(&ati_remote->interface->dev,
                        "Masked input from channel 0x%02x: data %02x, mask= 0x%02lx\n",
                        remote_num, data[2], channel_mask);
                return;
        }

        /*
         * MSB is a toggle code, though only used by some devices
         * (e.g. SnapStream Firefly)
         */
        scancode = data[2] & 0x7f;

        dbginfo(&ati_remote->interface->dev,
                "channel 0x%02x; key data %02x, scancode %02x\n",
                remote_num, data[2], scancode);

        if (scancode >= 0x70) {
                /*
                 * This is either a mouse or scrollwheel event, depending on
                 * the remote/keymap.
                 * Get the keycode assigned to scancode 0x78/0x70. If it is
                 * set, assume this is a scrollwheel up/down event.
                 */
                wheel_keycode = rc_g_keycode_from_table(ati_remote->rdev,
                                                        scancode & 0x78);

                if (wheel_keycode == KEY_RESERVED) {
                        /* scrollwheel was not mapped, assume mouse */

                        /* Look up event code index in the mouse translation
                         * table.
                         */
                        for (i = 0; ati_remote_tbl[i].kind != KIND_END; i++) {
                                if (scancode == ati_remote_tbl[i].data) {
                                        index = i;
                                        break;
                                }
                        }
                }
        }

        if (index >= 0 && ati_remote_tbl[index].kind == KIND_LITERAL) {
                /*
                 * The lsbit of the raw key code is a down/up flag.
                 * Invert it to match the input layer's conventions.
                 */
                input_event(dev, EV_KEY, ati_remote_tbl[index].code,
                        !(data[2] & 1));

                ati_remote->old_jiffies = jiffies;

        } else if (index < 0 || ati_remote_tbl[index].kind == KIND_FILTERED) {
                unsigned long now = jiffies;

                /* Filter duplicate events which happen "too close" together. */
                if (ati_remote->old_data == data[2] &&
                    time_before(now, ati_remote->old_jiffies +
                                     msecs_to_jiffies(repeat_filter))) {
                        ati_remote->repeat_count++;
                } else {
                        ati_remote->repeat_count = 0;
                        ati_remote->first_jiffies = now;
                }

                ati_remote->old_jiffies = now;

                /* Ensure we skip at least the 4 first duplicate events
                 * (generated by a single keypress), and continue skipping
                 * until repeat_delay msecs have passed.
                 */
                if (ati_remote->repeat_count > 0 &&
                    (ati_remote->repeat_count < 5 ||
                     time_before(now, ati_remote->first_jiffies +
                                      msecs_to_jiffies(repeat_delay))))
                        return;

                if (index >= 0) {
                        input_event(dev, EV_KEY, ati_remote_tbl[index].code, 1);
                        input_event(dev, EV_KEY, ati_remote_tbl[index].code, 0);
                } else {
                        /* Not a mouse event, hand it to rc-core. */
                        int count = 1;

                        if (wheel_keycode != KEY_RESERVED) {
                                /*
                                 * This is a scrollwheel event, send the
                                 * scroll up (0x78) / down (0x70) scancode
                                 * repeatedly as many times as indicated by
                                 * rest of the scancode.
                                 */
                                count = (scancode & 0x07) + 1;
                                scancode &= 0x78;
                        }

                        while (count--) {
                                /*
                                * We don't use the rc-core repeat handling yet as
                                * it would cause ghost repeats which would be a
                                * regression for this driver.
                                */
                                rc_keydown_notimeout(ati_remote->rdev, RC_TYPE_OTHER,
                                                     scancode, data[2]);
                                rc_keyup(ati_remote->rdev);
                        }
                        goto nosync;
                }

        } else if (ati_remote_tbl[index].kind == KIND_ACCEL) {
                signed char dx = ati_remote_tbl[index].code >> 8;
                signed char dy = ati_remote_tbl[index].code & 255;

                /*
                 * Other event kinds are from the directional control pad, and
                 * have an acceleration factor applied to them.  Without this
                 * acceleration, the control pad is mostly unusable.
                 */
                int acc = ati_remote_compute_accel(ati_remote);
                if (dx)
                        input_report_rel(dev, REL_X, dx * acc);
                if (dy)
                        input_report_rel(dev, REL_Y, dy * acc);
                ati_remote->old_jiffies = jiffies;

        } else {
                dev_dbg(&ati_remote->interface->dev, "ati_remote kind=%d\n",
                        ati_remote_tbl[index].kind);
                return;
        }
        input_sync(dev);
nosync:
        ati_remote->old_data = data[2];
}

/*
 * ati_remote_irq_in
 */
static void ati_remote_irq_in(struct urb *urb)
{
        struct ati_remote *ati_remote = urb->context;
        int retval;

        switch (urb->status) {
        case 0:                 /* success */
                ati_remote_input_report(urb);
                break;
        case -ECONNRESET:       /* unlink */
        case -ENOENT:
        case -ESHUTDOWN:
                dev_dbg(&ati_remote->interface->dev,
                        "%s: urb error status, unlink?\n",
                        __func__);
                return;
        default:                /* error */
                dev_dbg(&ati_remote->interface->dev,
                        "%s: Nonzero urb status %d\n",
                        __func__, urb->status);
        }

        retval = usb_submit_urb(urb, GFP_ATOMIC);
        if (retval)
                dev_err(&ati_remote->interface->dev,
                        "%s: usb_submit_urb()=%d\n",
                        __func__, retval);
}

/*
 * ati_remote_alloc_buffers
 */
static int ati_remote_alloc_buffers(struct usb_device *udev,
                                    struct ati_remote *ati_remote)
{
        ati_remote->inbuf = usb_alloc_coherent(udev, DATA_BUFSIZE, GFP_ATOMIC,
                                               &ati_remote->inbuf_dma);
        if (!ati_remote->inbuf)
                return -1;

        ati_remote->outbuf = usb_alloc_coherent(udev, DATA_BUFSIZE, GFP_ATOMIC,
                                                &ati_remote->outbuf_dma);
        if (!ati_remote->outbuf)
                return -1;

        ati_remote->irq_urb = usb_alloc_urb(0, GFP_KERNEL);
        if (!ati_remote->irq_urb)
                return -1;

        ati_remote->out_urb = usb_alloc_urb(0, GFP_KERNEL);
        if (!ati_remote->out_urb)
                return -1;

        return 0;
}

/*
 * ati_remote_free_buffers
 */
static void ati_remote_free_buffers(struct ati_remote *ati_remote)
{
        usb_free_urb(ati_remote->irq_urb);
        usb_free_urb(ati_remote->out_urb);

        usb_free_coherent(ati_remote->udev, DATA_BUFSIZE,
                ati_remote->inbuf, ati_remote->inbuf_dma);

        usb_free_coherent(ati_remote->udev, DATA_BUFSIZE,
                ati_remote->outbuf, ati_remote->outbuf_dma);
}

static void ati_remote_input_init(struct ati_remote *ati_remote)
{
        struct input_dev *idev = ati_remote->idev;
        int i;

        idev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL);
        idev->keybit[BIT_WORD(BTN_MOUSE)] = BIT_MASK(BTN_LEFT) |
                BIT_MASK(BTN_RIGHT) | BIT_MASK(BTN_SIDE) | BIT_MASK(BTN_EXTRA);
        idev->relbit[0] = BIT_MASK(REL_X) | BIT_MASK(REL_Y);
        for (i = 0; ati_remote_tbl[i].kind != KIND_END; i++)
                if (ati_remote_tbl[i].kind == KIND_LITERAL ||
                    ati_remote_tbl[i].kind == KIND_FILTERED)
                        __set_bit(ati_remote_tbl[i].code, idev->keybit);

        input_set_drvdata(idev, ati_remote);

        idev->open = ati_remote_input_open;
        idev->close = ati_remote_input_close;

        idev->name = ati_remote->mouse_name;
        idev->phys = ati_remote->mouse_phys;

        usb_to_input_id(ati_remote->udev, &idev->id);
        idev->dev.parent = &ati_remote->interface->dev;
}

static void ati_remote_rc_init(struct ati_remote *ati_remote)
{
        struct rc_dev *rdev = ati_remote->rdev;

        rdev->priv = ati_remote;
        rdev->driver_type = RC_DRIVER_SCANCODE;
        rdev->allowed_protocols = RC_BIT_OTHER;
        rdev->driver_name = "ati_remote";

        rdev->open = ati_remote_rc_open;
        rdev->close = ati_remote_rc_close;

        rdev->input_name = ati_remote->rc_name;
        rdev->input_phys = ati_remote->rc_phys;

        usb_to_input_id(ati_remote->udev, &rdev->input_id);
        rdev->dev.parent = &ati_remote->interface->dev;
}

static int ati_remote_initialize(struct ati_remote *ati_remote)
{
        struct usb_device *udev = ati_remote->udev;
        int pipe, maxp;

        init_waitqueue_head(&ati_remote->wait);

        /* Set up irq_urb */
        pipe = usb_rcvintpipe(udev, ati_remote->endpoint_in->bEndpointAddress);
        maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
        maxp = (maxp > DATA_BUFSIZE) ? DATA_BUFSIZE : maxp;

        usb_fill_int_urb(ati_remote->irq_urb, udev, pipe, ati_remote->inbuf,
                         maxp, ati_remote_irq_in, ati_remote,
                         ati_remote->endpoint_in->bInterval);
        ati_remote->irq_urb->transfer_dma = ati_remote->inbuf_dma;
        ati_remote->irq_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;

        /* Set up out_urb */
        pipe = usb_sndintpipe(udev, ati_remote->endpoint_out->bEndpointAddress);
        maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
        maxp = (maxp > DATA_BUFSIZE) ? DATA_BUFSIZE : maxp;

        usb_fill_int_urb(ati_remote->out_urb, udev, pipe, ati_remote->outbuf,
                         maxp, ati_remote_irq_out, ati_remote,
                         ati_remote->endpoint_out->bInterval);
        ati_remote->out_urb->transfer_dma = ati_remote->outbuf_dma;
        ati_remote->out_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;

        /* send initialization strings */
        if ((ati_remote_sendpacket(ati_remote, 0x8004, init1)) ||
            (ati_remote_sendpacket(ati_remote, 0x8007, init2))) {
                dev_err(&ati_remote->interface->dev,
                         "Initializing ati_remote hardware failed.\n");
                return -EIO;
        }

        return 0;
}

/*
 * ati_remote_probe
 */
static int ati_remote_probe(struct usb_interface *interface,
        const struct usb_device_id *id)
{
        struct usb_device *udev = interface_to_usbdev(interface);
        struct usb_host_interface *iface_host = interface->cur_altsetting;
        struct usb_endpoint_descriptor *endpoint_in, *endpoint_out;
        struct ati_receiver_type *type = (struct ati_receiver_type *)id->driver_info;
        struct ati_remote *ati_remote;
        struct input_dev *input_dev;
        struct rc_dev *rc_dev;
        int err = -ENOMEM;

        if (iface_host->desc.bNumEndpoints != 2) {
                err("%s: Unexpected desc.bNumEndpoints\n", __func__);
                return -ENODEV;
        }

        endpoint_in = &iface_host->endpoint[0].desc;
        endpoint_out = &iface_host->endpoint[1].desc;

        if (!usb_endpoint_is_int_in(endpoint_in)) {
                err("%s: Unexpected endpoint_in\n", __func__);
                return -ENODEV;
        }
        if (le16_to_cpu(endpoint_in->wMaxPacketSize) == 0) {
                err("%s: endpoint_in message size==0? \n", __func__);
                return -ENODEV;
        }

        ati_remote = kzalloc(sizeof (struct ati_remote), GFP_KERNEL);
        rc_dev = rc_allocate_device();
        if (!ati_remote || !rc_dev)
                goto exit_free_dev_rdev;

        /* Allocate URB buffers, URBs */
        if (ati_remote_alloc_buffers(udev, ati_remote))
                goto exit_free_buffers;

        ati_remote->endpoint_in = endpoint_in;
        ati_remote->endpoint_out = endpoint_out;
        ati_remote->udev = udev;
        ati_remote->rdev = rc_dev;
        ati_remote->interface = interface;

        usb_make_path(udev, ati_remote->rc_phys, sizeof(ati_remote->rc_phys));
        strlcpy(ati_remote->mouse_phys, ati_remote->rc_phys,
                sizeof(ati_remote->mouse_phys));

        strlcat(ati_remote->rc_phys, "/input0", sizeof(ati_remote->rc_phys));
        strlcat(ati_remote->mouse_phys, "/input1", sizeof(ati_remote->mouse_phys));

        snprintf(ati_remote->rc_name, sizeof(ati_remote->rc_name), "%s%s%s",
                udev->manufacturer ?: "",
                udev->manufacturer && udev->product ? " " : "",
                udev->product ?: "");

        if (!strlen(ati_remote->rc_name))
                snprintf(ati_remote->rc_name, sizeof(ati_remote->rc_name),
                        DRIVER_DESC "(%04x,%04x)",
                        le16_to_cpu(ati_remote->udev->descriptor.idVendor),
                        le16_to_cpu(ati_remote->udev->descriptor.idProduct));

        snprintf(ati_remote->mouse_name, sizeof(ati_remote->mouse_name),
                 "%s mouse", ati_remote->rc_name);

        rc_dev->map_name = RC_MAP_ATI_X10; /* default map */

        /* set default keymap according to receiver model */
        if (type) {
                if (type->default_keymap)
                        rc_dev->map_name = type->default_keymap;
                else if (type->get_default_keymap)
                        rc_dev->map_name = type->get_default_keymap(interface);
        }

        ati_remote_rc_init(ati_remote);
        mutex_init(&ati_remote->open_mutex);

        /* Device Hardware Initialization - fills in ati_remote->idev from udev. */
        err = ati_remote_initialize(ati_remote);
        if (err)
                goto exit_kill_urbs;

        /* Set up and register rc device */
        err = rc_register_device(ati_remote->rdev);
        if (err)
                goto exit_kill_urbs;

        /* use our delay for rc_dev */
        ati_remote->rdev->input_dev->rep[REP_DELAY] = repeat_delay;

        /* Set up and register mouse input device */
        if (mouse) {
                input_dev = input_allocate_device();
                if (!input_dev) {
                        err = -ENOMEM;
                        goto exit_unregister_device;
                }

                ati_remote->idev = input_dev;
                ati_remote_input_init(ati_remote);
                err = input_register_device(input_dev);

                if (err)
                        goto exit_free_input_device;
        }

        usb_set_intfdata(interface, ati_remote);
        return 0;

 exit_free_input_device:
        input_free_device(input_dev);
 exit_unregister_device:
        rc_unregister_device(rc_dev);
        rc_dev = NULL;
 exit_kill_urbs:
        usb_kill_urb(ati_remote->irq_urb);
        usb_kill_urb(ati_remote->out_urb);
 exit_free_buffers:
        ati_remote_free_buffers(ati_remote);
 exit_free_dev_rdev:
         rc_free_device(rc_dev);
        kfree(ati_remote);
        return err;
}

/*
 * ati_remote_disconnect
 */
static void ati_remote_disconnect(struct usb_interface *interface)
{
        struct ati_remote *ati_remote;

        ati_remote = usb_get_intfdata(interface);
        usb_set_intfdata(interface, NULL);
        if (!ati_remote) {
                dev_warn(&interface->dev, "%s - null device?\n", __func__);
                return;
        }

        usb_kill_urb(ati_remote->irq_urb);
        usb_kill_urb(ati_remote->out_urb);
        if (ati_remote->idev)
                input_unregister_device(ati_remote->idev);
        rc_unregister_device(ati_remote->rdev);
        ati_remote_free_buffers(ati_remote);
        kfree(ati_remote);
}

/* usb specific object to register with the usb subsystem */
static struct usb_driver ati_remote_driver = {
        .name         = "ati_remote",
        .probe        = ati_remote_probe,
        .disconnect   = ati_remote_disconnect,
        .id_table     = ati_remote_table,
};

module_usb_driver(ati_remote_driver);

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");