#include "hid-tmt300rs.h"

static void t300rs_int_callback(struct urb *urb){
    if(urb->status){
        hid_warn(urb->dev, "urb status %i received\n", urb->status);
    }

    usb_free_urb(urb);
}

static struct t300rs_device_entry *t300rs_get_device(struct hid_device *hdev){
    struct t300rs_data *drv_data;
    struct t300rs_device_entry *t300rs;

    spin_lock_irqsave(&lock, lock_flags);
    drv_data = hid_get_drvdata(hdev);
    if(!drv_data){
        hid_err(hdev, "private data not found\n");
        return NULL;
    }

    t300rs = drv_data->device_props;
    if(!t300rs){
        hid_err(hdev, "device properties not found\n");
        return NULL;
    }
    spin_unlock_irqrestore(&lock, lock_flags);

    return t300rs;
}

static int t300rs_send_int(struct input_dev *dev, u8 *send_buffer, int *trans){
    struct hid_device *hdev = input_get_drvdata(dev);
    struct t300rs_device_entry *t300rs;
    struct usb_device *usbdev;
    struct usb_interface *usbif;
    struct usb_host_endpoint *ep;
    struct urb *urb = usb_alloc_urb(0, GFP_ATOMIC);

    t300rs = t300rs_get_device(hdev);
    if(!t300rs){
        hid_err(hdev, "could not get device\n");
    }

    usbdev = t300rs->usbdev;
    usbif = t300rs->usbif;
    ep = &usbif->cur_altsetting->endpoint[1];

    usb_fill_int_urb(
            urb,
            usbdev,
            usb_sndintpipe(usbdev, 1),
            send_buffer,
            T300RS_BUFFER_LENGTH,
            t300rs_int_callback,
            hdev,
            ep->desc.bInterval
            );

    return usb_submit_urb(urb, GFP_ATOMIC);
}

static int t300rs_play_effect(struct t300rs_device_entry *t300rs, struct t300rs_effect_state *state){
    u8 *send_buffer = kzalloc(T300RS_BUFFER_LENGTH, GFP_ATOMIC);
    int ret, trans;

    send_buffer[0] = 0x60;
    send_buffer[2] = state->effect.id + 1;
    send_buffer[3] = 0x89;
    send_buffer[4] = 0x01;

    ret = t300rs_send_int(t300rs->input_dev, send_buffer, &trans);
    if(ret){
        hid_err(t300rs->hdev, "failed starting effect play\n");
    }

    kfree(send_buffer);
    return ret;
}

static int t300rs_stop_effect(struct t300rs_device_entry *t300rs, struct t300rs_effect_state *state){
    u8 *send_buffer = kzalloc(T300RS_BUFFER_LENGTH, GFP_ATOMIC);
    int ret, trans;

    send_buffer[0] = 0x60;
    send_buffer[2] = state->effect.id + 1;
    send_buffer[3] = 0x89;

    ret = t300rs_send_int(t300rs->input_dev, send_buffer, &trans);
    if(ret){
        hid_err(t300rs->hdev, "failed stopping effect play\n");
    }

    kfree(send_buffer);
    return ret;
}

static void t300rs_fill_envelope(u8 *send_buffer, int i, s16 level, u16 duration, struct ff_envelope *envelope){
    u16 attack_length = (duration * envelope->attack_length) / 0x7fff;
    u16 attack_level = (level * envelope->attack_level) / 0x7fff;
    u16 fade_length = (duration * envelope->fade_length) / 0x7fff;
    u16 fade_level = (level * envelope->fade_level) / 0x7fff;

    attack_length = cpu_to_le16(attack_length);
    attack_level = cpu_to_le16(attack_level);
    fade_length = cpu_to_le16(fade_length);
    fade_level = cpu_to_le16(fade_level);

    send_buffer[i    ] = attack_length & 0xff;
    send_buffer[i + 1] = attack_length >> 8;
    send_buffer[i + 2] = attack_level & 0xff;
    send_buffer[i + 3] = attack_level >> 8;
    send_buffer[i + 4] = fade_length & 0xff;
    send_buffer[i + 5] = fade_length >> 8;
    send_buffer[i + 6] = fade_level & 0xff;
    send_buffer[i + 7] = fade_level >> 8;
}

static int t300rs_upload_constant(struct t300rs_device_entry *t300rs, struct t300rs_effect_state *state){
    u8 *send_buffer = kzalloc(T300RS_BUFFER_LENGTH, GFP_ATOMIC);
    struct ff_effect effect = state->effect;
    struct ff_constant_effect constant = state->effect.u.constant;
    s16 level, le_level;
    u16 duration, le_offset, le_duration;

    int ret, trans;
    
    /* currently this driver doesn't support dynamic effect updating quite like
     * many games would assume. There's not a huge drawback to this method, the
     * wheel maybe feels a bit more jittery because of this but it's not a
     * massive downside. At some point in the future I'd like to improve the
     * dynamic updating, but this will do for now.
     * */
    if(test_bit(FF_EFFECT_PLAYING, &state->flags)){
        t300rs_stop_effect(t300rs, state);
    }

    level = (constant.level * fixp_sin16(effect.direction * 360 / 0x10000)) / 0x7fff;
    duration = effect.replay.length;

    le_level = cpu_to_le16(level);
    le_offset = cpu_to_le16(effect.replay.delay);
    le_duration = cpu_to_le16(duration);

    send_buffer[0] = 0x60;
    send_buffer[2] = effect.id + 1;
    send_buffer[3] = 0x6a;

    send_buffer[4] = le_level & 0xff;
    send_buffer[5] = le_level >> 8;

    t300rs_fill_envelope(send_buffer, 6, level,
            duration, &constant.envelope);

    send_buffer[15] = 0x4f;

    send_buffer[16] = le_duration & 0xff;
    send_buffer[17] = le_duration >> 8;

    send_buffer[20] = le_offset & 0xff;
    send_buffer[21] = le_offset >> 8;

    send_buffer[23] = 0xff;
    send_buffer[24] = 0xff;

    ret = t300rs_send_int(t300rs->input_dev, send_buffer, &trans);
    if(ret){
        hid_err(t300rs->hdev, "failed uploading constant effect\n");
    }

    if(test_bit(FF_EFFECT_PLAYING, &state->flags)){
        t300rs_play_effect(t300rs, state);
    }

    kfree(send_buffer);
    return ret;
}

static int t300rs_upload_ramp(struct t300rs_device_entry *t300rs, struct t300rs_effect_state *state){
    u8 *send_buffer = kzalloc(T300RS_BUFFER_LENGTH, GFP_ATOMIC);
    struct ff_effect effect = state->effect;
    struct ff_ramp_effect ramp = state->effect.u.ramp;
    int ret, trans;
    u16 difference, le_difference, top, bottom, le_duration, le_offset;
    s16 level, le_level;

    if(test_bit(FF_EFFECT_PLAYING, &state->flags)){
        t300rs_stop_effect(t300rs, state);
    }

    top = ramp.end_level > ramp.start_level ? ramp.end_level : ramp.start_level;
    bottom = ramp.end_level > ramp.start_level ? ramp.start_level : ramp.end_level;


    difference = ((top - bottom) * fixp_sin16(effect.direction * 360 / 0x10000)) / 0x7fff;
    level = (top * fixp_sin16(effect.direction * 360 / 0x10000)) / 0x7fff;
    
    le_difference = cpu_to_le16(difference);
    le_level = cpu_to_le16(level);
    le_duration = cpu_to_le16(effect.replay.length);
    le_offset = cpu_to_le16(effect.replay.delay);

    send_buffer[0] = 0x60;
    send_buffer[1] = effect.id + 1;
    send_buffer[2] = 0x6b;
    
    send_buffer[3] = le_difference & 0xff;
    send_buffer[4] = le_difference >> 8;

    send_buffer[5] = le_level & 0xff; 
    send_buffer[6] = le_level >> 8;

    send_buffer[9] = le_duration & 0xff;
    send_buffer[10] = le_duration >> 8;

    send_buffer[12] = 0x80;

    t300rs_fill_envelope(send_buffer, 14, level,
            effect.replay.length, &ramp.envelope);

    send_buffer[22] = ramp.end_level > ramp.start_level ? 0x04 : 0x05;
    send_buffer[23] = 0x4f;

    send_buffer[24] = le_duration & 0xff;
    send_buffer[25] = le_duration >> 8;

    send_buffer[28] = le_offset & 0xff;
    send_buffer[29] = le_offset >> 8;

    send_buffer[31] = 0xff;
    send_buffer[32] = 0xff;

    ret = t300rs_send_int(t300rs->input_dev, send_buffer, &trans);
    if(ret){
        hid_err(t300rs->hdev, "failed uploading ramp");
    }

    if(test_bit(FF_EFFECT_PLAYING, &state->flags)){
        t300rs_play_effect(t300rs, state);
    }

    kfree(send_buffer);
    return ret;
}

static int t300rs_upload_spring(struct t300rs_device_entry *t300rs, struct t300rs_effect_state *state){
    u8 *send_buffer = kzalloc(T300RS_BUFFER_LENGTH, GFP_ATOMIC);
    struct ff_effect effect = state->effect;
    /* we only care about the first axis */
    struct ff_condition_effect spring = state->effect.u.condition[0];
    int ret, trans;
    u16 le_right_coeff, le_left_coeff, le_deadband_right, le_deadband_left,
        le_duration, le_offset;
    
    if(test_bit(FF_EFFECT_PLAYING, &state->flags)){
        t300rs_stop_effect(t300rs, state);
    }

    send_buffer[0] = 0x60;
    send_buffer[2] = effect.id + 1;
    send_buffer[3] = 0x64;
    
    le_right_coeff = cpu_to_le16(spring.right_coeff);
    le_left_coeff = cpu_to_le16(spring.left_coeff);

    le_deadband_right = cpu_to_le16(0xfffe - spring.deadband - spring.center);
    le_deadband_left = cpu_to_le16(0xfffe - spring.deadband + spring.center);

    le_duration = cpu_to_le16(effect.replay.length);
    le_offset = cpu_to_le16(effect.replay.delay);

    send_buffer[4] = le_right_coeff & 0xff;
    send_buffer[5] = le_right_coeff >> 8;

    send_buffer[6] = le_left_coeff & 0xff;
    send_buffer[7] = le_left_coeff >> 8;

    send_buffer[8] = le_deadband_right & 0xff;
    send_buffer[9] = le_deadband_right >> 8;

    send_buffer[10] = le_deadband_left & 0xff;
    send_buffer[11] = le_deadband_left >> 8;

    memcpy(&send_buffer[12], spring_values, ARRAY_SIZE(spring_values));
    send_buffer[29] = 0x4f;

    send_buffer[30] = le_duration & 0xff;
    send_buffer[31] = le_duration >> 8;

    send_buffer[34] = le_offset & 0xff;
    send_buffer[35] = le_offset >> 8;

    send_buffer[37] = 0xff;
    send_buffer[38] = 0xff;

    ret = t300rs_send_int(t300rs->input_dev, send_buffer, &trans);
    if(ret){
        hid_err(t300rs->hdev, "failed uploading spring\n");
    }

    if(test_bit(FF_EFFECT_PLAYING, &state->flags)){
        t300rs_play_effect(t300rs, state);
    }

    kfree(send_buffer);
    return ret;
}

static int t300rs_upload_damper(struct t300rs_device_entry *t300rs, struct t300rs_effect_state *state){
    u8 *send_buffer = kzalloc(T300RS_BUFFER_LENGTH, GFP_ATOMIC);
    struct ff_effect effect = state->effect;
    /* we only care about the first axis */
    struct ff_condition_effect spring = state->effect.u.condition[0];
    int ret, trans;
    u16 le_right_coeff, le_left_coeff, le_deadband_right, le_deadband_left,
        le_duration, le_offset;
    
    if(test_bit(FF_EFFECT_PLAYING, &state->flags)){
        t300rs_stop_effect(t300rs, state);
    }

    send_buffer[0] = 0x60;
    send_buffer[2] = effect.id + 1;
    send_buffer[3] = 0x64;
    
    le_right_coeff = cpu_to_le16(spring.right_coeff);
    le_left_coeff = cpu_to_le16(spring.left_coeff);

    le_deadband_right = cpu_to_le16(0xfffe - spring.deadband - spring.center);
    le_deadband_left = cpu_to_le16(0xfffe - spring.deadband + spring.center);

    le_duration = cpu_to_le16(effect.replay.length);
    le_offset = cpu_to_le16(effect.replay.delay);

    send_buffer[4] = le_right_coeff & 0xff;
    send_buffer[5] = le_right_coeff >> 8;

    send_buffer[6] = le_left_coeff & 0xff;
    send_buffer[7] = le_left_coeff >> 8;

    send_buffer[8] = le_deadband_right & 0xff;
    send_buffer[9] = le_deadband_right >> 8;

    send_buffer[10] = le_deadband_left & 0xff;
    send_buffer[11] = le_deadband_left >> 8;

    memcpy(&send_buffer[12], damper_values, ARRAY_SIZE(damper_values));
    send_buffer[29] = 0x4f;

    send_buffer[30] = le_duration & 0xff;
    send_buffer[31] = le_duration >> 8;

    send_buffer[34] = le_offset & 0xff;
    send_buffer[35] = le_offset >> 8;

    send_buffer[37] = 0xff;
    send_buffer[38] = 0xff;

    ret = t300rs_send_int(t300rs->input_dev, send_buffer, &trans);
    if(ret){
        hid_err(t300rs->hdev, "failed uploading spring\n");
    }

    if(test_bit(FF_EFFECT_PLAYING, &state->flags)){
        t300rs_play_effect(t300rs, state);
    }

    kfree(send_buffer);
    return ret;
}

static int t300rs_upload_periodic(struct t300rs_device_entry *t300rs, struct t300rs_effect_state *state){
    u8 *send_buffer = kzalloc(T300RS_BUFFER_LENGTH, GFP_ATOMIC);
    struct ff_effect effect = state->effect;
    struct ff_periodic_effect periodic = state->effect.u.periodic;
    int ret, trans;
    u16 magnitude, le_magnitude, le_phase, le_period, le_offset, le_duration;
    s16 le_periodic_offset;

    if(test_bit(FF_EFFECT_PLAYING, &state->flags)){
        t300rs_stop_effect(t300rs, state);
    }

    magnitude = (periodic.magnitude * fixp_sin16(effect.direction * 360 / 0x10000)) / 0x7fff;

    le_magnitude = cpu_to_le16(magnitude);
    le_phase = cpu_to_le16(periodic.phase);
    le_periodic_offset = cpu_to_le16(periodic.offset);
    le_period = cpu_to_le16(periodic.period);
    le_offset = cpu_to_le16(effect.replay.delay);
    le_duration = cpu_to_le16(effect.replay.length);
    
        send_buffer[0] = 0x60;
    send_buffer[2] = effect.id + 1;
    send_buffer[3] = 0x6b;
    
    send_buffer[4] = le_magnitude & 0xff;
    send_buffer[5] = le_magnitude >> 8;

    send_buffer[6] = le_phase & 0xff;
    send_buffer[7] = le_phase >> 8;

    send_buffer[8] = le_periodic_offset & 0xff;
    send_buffer[9] = le_periodic_offset >> 8;

    send_buffer[10] = le_period & 0xff;
    send_buffer[11] = le_period >> 8;

    send_buffer[13] = 0x80;

    t300rs_fill_envelope(send_buffer, 14, magnitude,
            effect.replay.length, &periodic.envelope);

    send_buffer[22] = periodic.waveform - 0x57;
    send_buffer[23] = 0x4f;

    send_buffer[24] = le_duration & 0xff;
    send_buffer[25] = le_duration >> 8;

    send_buffer[27] = le_offset & 0xff;
    send_buffer[28] = le_offset >> 8;

    send_buffer[30] = 0xff;
    send_buffer[31] = 0xff;
    
    ret = t300rs_send_int(t300rs->input_dev, send_buffer, &trans);
    if(ret){
        hid_err(t300rs->hdev, "failed uploading periodic effect");
    }
     
    if(test_bit(FF_EFFECT_PLAYING, &state->flags)){
        t300rs_play_effect(t300rs, state);
    }

    kfree(send_buffer);
    return ret;
}

static int t300rs_upload_effect(struct t300rs_device_entry *t300rs, struct t300rs_effect_state *state){
    switch(state->effect.type){
        case FF_CONSTANT:
            return t300rs_upload_constant(t300rs, state);
        case FF_RAMP:
            return t300rs_upload_ramp(t300rs, state);
        case FF_SPRING:
            return t300rs_upload_spring(t300rs, state);
        case FF_DAMPER:
        case FF_FRICTION:
        case FF_INERTIA:
            return t300rs_upload_damper(t300rs, state);
        case FF_PERIODIC:
            return t300rs_upload_periodic(t300rs, state);
        default:
            hid_err(t300rs->hdev, "invalid effect type: %x", state->effect.type);
            return -1;
    }
} 

static int t300rs_timer_helper(struct t300rs_device_entry *t300rs){
    struct t300rs_effect_state *state;
    unsigned long jiffies_now = JIFFIES2MS(jiffies);
    int max_count = 0, effect_id, ret;
    
    for(effect_id = 0; effect_id < T300RS_MAX_EFFECTS; ++effect_id){
        
        state = &t300rs->states[effect_id];

         if(test_bit(FF_EFFECT_PLAYING, &state->flags)){
            if((jiffies_now - state->start_time) >= state->effect.replay.length){
                __clear_bit(FF_EFFECT_PLAYING, &state->flags);

                if(state->count){
                    __set_bit(FF_EFFECT_QUEUE_START, &state->flags);
                }
            }
        }

        if(test_bit(FF_EFFECT_QUEUE_UPLOAD, &state->flags)){
            __clear_bit(FF_EFFECT_QUEUE_UPLOAD, &state->flags);

            ret = t300rs_upload_effect(t300rs, state);
            if(ret){
                hid_err(t300rs->hdev, "failed uploading effects");
                return ret;
            }
        }

        if(test_bit(FF_EFFECT_QUEUE_START, &state->flags)){
            __clear_bit(FF_EFFECT_QUEUE_START, &state->flags);
            __set_bit(FF_EFFECT_PLAYING, &state->flags);

            ret = t300rs_play_effect(t300rs, state);
            if(ret){
                hid_err(t300rs->hdev, "failed starting effects\n");
                return ret;
            }

            if(state->count){
                state->count--;
            }
        }

        if(test_bit(FF_EFFECT_QUEUE_STOP, &state->flags)){
            __clear_bit(FF_EFFECT_QUEUE_STOP, &state->flags);
            __clear_bit(FF_EFFECT_PLAYING, &state->flags);

            ret = t300rs_stop_effect(t300rs, state);
            if(ret){
                hid_err(t300rs->hdev, "failed stopping effect\n");
                return ret;
            }
        }

        if(state->count > max_count){
            max_count = state->count;
        }
    }

    return max_count;
}

static enum hrtimer_restart t300rs_timer(struct hrtimer *t){
    struct t300rs_device_entry *t300rs = container_of(t, struct t300rs_device_entry, hrtimer);
    int max_count;

    max_count = t300rs_timer_helper(t300rs);
    
    if(max_count > 0){
        hrtimer_forward_now(&t300rs->hrtimer, ms_to_ktime(timer_msecs));
        return HRTIMER_RESTART;
    } else {
        return HRTIMER_NORESTART;
    }
} 


static int t300rs_upload(struct input_dev *dev, struct ff_effect *effect, struct ff_effect *old){
    struct hid_device *hdev = input_get_drvdata(dev);
    struct t300rs_device_entry *t300rs;
    struct t300rs_effect_state *state;

    t300rs = t300rs_get_device(hdev);
    
    if(effect->type == FF_PERIODIC && effect->u.periodic.period == 0){
        return -EINVAL;
    }

    if(effect->id > t300rs->max_id){
        t300rs->max_id = effect->id;
    }

    state = &t300rs->states[effect->id];

    spin_lock_irqsave(&t300rs->lock, t300rs->lock_flags);

    state->effect = *effect;
    __set_bit(FF_EFFECT_QUEUE_UPLOAD, &state->flags);

    spin_unlock_irqrestore(&t300rs->lock, t300rs->lock_flags);

    return 0;
}

static int t300rs_play(struct input_dev *dev, int effect_id, int value){
    struct hid_device *hdev = input_get_drvdata(dev);
    struct t300rs_device_entry *t300rs;
    struct t300rs_effect_state *state;

    t300rs = t300rs_get_device(hdev);

    state = &t300rs->states[effect_id];
    
    spin_lock_irqsave(&t300rs->lock, t300rs->lock_flags);

    if(value > 0){
        if(test_bit(FF_EFFECT_QUEUE_START, &state->flags)){
            __set_bit(FF_EFFECT_QUEUE_STOP, &state->flags);
        } else {
            t300rs->effects_used++;
        }

        state->count = value;
        state->start_time = JIFFIES2MS(jiffies);
        __set_bit(FF_EFFECT_QUEUE_START, &state->flags);

    } else {
        __set_bit(FF_EFFECT_QUEUE_STOP, &state->flags);
        t300rs->effects_used--;
    }

    if(!hrtimer_active(&t300rs->hrtimer)){
        hrtimer_start(&t300rs->hrtimer, ms_to_ktime(timer_msecs), HRTIMER_MODE_REL);
    }

    spin_unlock_irqrestore(&t300rs->lock, t300rs->lock_flags);
    return 0;
}

/* we should set a default range */
static ssize_t t300rs_range_store(struct device *dev, struct device_attribute *attr,
        const char *buf, size_t count){
    struct hid_device *hdev = to_hid_device(dev);
    struct t300rs_device_entry *t300rs;
    u8 *send_buffer = kzalloc(T300RS_BUFFER_LENGTH, GFP_ATOMIC);
    u16 range = simple_strtoul(buf, NULL, 10);
    int ret, trans;

    t300rs = t300rs_get_device(hdev);

    if(range < 0x097b){
        range = 0x097b;
    }

    range = cpu_to_le16(range);

    send_buffer[0] = 0x60;
    send_buffer[1] = 0x08;
    send_buffer[2] = 0x11;
    send_buffer[3] = range & 0xff;
    send_buffer[4] = range >> 8;

    ret = t300rs_send_int(t300rs->input_dev, send_buffer, &trans);
    if(ret){
        hid_err(hdev, "failed sending interrupts\n");
        return -1;
    }

    t300rs->range = range;
    kfree(send_buffer);
    return count;
}

static ssize_t t300rs_range_show(struct device *dev, struct device_attribute *attr,
        char *buf){
    struct hid_device *hdev = to_hid_device(dev);
    struct t300rs_device_entry *t300rs;

    t300rs = t300rs_get_device(hdev);

    return t300rs->range;
}

static DEVICE_ATTR(range, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH, t300rs_range_show, t300rs_range_store);

static void t300rs_set_autocenter(struct input_dev *dev, u16 value){
    struct hid_device *hdev = input_get_drvdata(dev);
    u8 *send_buffer = kzalloc(T300RS_BUFFER_LENGTH, GFP_ATOMIC);
    u16 le_value = cpu_to_le16(value);
    int ret, trans;

    send_buffer[0] = 0x60;
    send_buffer[1] = 0x08;
    send_buffer[2] = 0x03;
    
    send_buffer[3] = le_value & 0xff;
    send_buffer[4] = le_value >> 8;

    ret = t300rs_send_int(dev, send_buffer, &trans);
    if(ret){
        hid_err(hdev, "failed setting autocenter");
    }

    kfree(send_buffer);
}

static void t300rs_set_gain(struct input_dev *dev, u16 gain){
    struct hid_device *hdev = input_get_drvdata(dev);
    u8 *send_buffer = kzalloc(T300RS_BUFFER_LENGTH, GFP_ATOMIC);
    int ret, trans;

    send_buffer[0] = 0x60;
    send_buffer[1] = 0x02;
    send_buffer[2] = SCALE_VALUE_U16(gain, 8);
    
    ret = t300rs_send_int(dev, send_buffer, &trans);
    if(ret){
        hid_err(hdev, "failed setting gain\n");
    }

    kfree(send_buffer);
}

static void t300rs_destroy(struct ff_device *ff){
    /* maybe not temp? */
    return;
}


static int t300rs_open(struct input_dev *dev){
    struct t300rs_device_entry *t300rs;
    struct hid_device *hdev = input_get_drvdata(dev);
    u8 *send_buffer = kzalloc(T300RS_BUFFER_LENGTH, GFP_ATOMIC);
    int ret, trans;

    t300rs = t300rs_get_device(hdev);

    send_buffer[0] = 0x60;
    send_buffer[1] = 0x01;
    send_buffer[2] = 0x04;

    ret = t300rs_send_int(dev, send_buffer, &trans); 
    if(ret){
        hid_err(hdev, "failed sending interrupts\n");
        goto err;
    }
    memset(send_buffer, 0, T300RS_BUFFER_LENGTH);

    send_buffer[0] = 0x60;
    send_buffer[1] = 0x12;
    send_buffer[2] = 0xbf;
    send_buffer[3] = 0x04;
    send_buffer[6] = 0x03;
    send_buffer[7] = 0xb7;
    send_buffer[8] = 0x1e;

    ret = t300rs_send_int(dev, send_buffer, &trans); 
    if(ret){
        hid_err(hdev, "failed sending interrupts\n");
        goto err;
    }
    memset(send_buffer, 0, T300RS_BUFFER_LENGTH);

    send_buffer[0] = 0x60;
    send_buffer[1] = 0x01;
    send_buffer[2] = 0x05;

    ret = t300rs_send_int(dev, send_buffer, &trans); 
    if(ret){
        hid_err(hdev, "failed sending interrupts\n");
        goto err;
    }

err:
    kfree(send_buffer);
    return t300rs->open(dev);
}

static void t300rs_close(struct input_dev *dev){
    int ret, trans;
    struct hid_device *hdev = input_get_drvdata(dev);
    struct t300rs_device_entry *t300rs;
    u8 *send_buffer = kzalloc(T300RS_BUFFER_LENGTH, GFP_ATOMIC);
    
    t300rs = t300rs_get_device(hdev);

    send_buffer[0] = 0x60;
    send_buffer[1] = 0x01;

    ret = t300rs_send_int(dev, send_buffer, &trans);
    if(ret){
        hid_err(hdev, "failed sending interrupts\n");
        goto err;
    }
err:
    kfree(send_buffer);
    t300rs->close(dev);
    return;
}

int t300rs_init(struct hid_device *hdev, const signed short *ff_bits){
    struct t300rs_device_entry *t300rs;
    struct t300rs_data *drv_data;
    struct list_head *report_list;
    struct hid_input *hidinput = list_entry(hdev->inputs.next,
            struct hid_input, list);
    struct input_dev *input_dev = hidinput->input;
    struct device *dev = &hdev->dev;
    struct usb_interface *usbif = to_usb_interface(dev->parent);
    struct usb_device *usbdev = interface_to_usbdev(usbif);
    struct hid_report *report;
    struct ff_device *ff;
    char range[10] = "54000"; /* approx 900 degress */
    int i, ret;

    drv_data = hid_get_drvdata(hdev);
    if(!drv_data){
        hid_err(hdev, "private driver data not allocated\n");
        ret = -ENOMEM;
        goto err;
    }

    t300rs = kzalloc(sizeof(struct t300rs_device_entry), GFP_ATOMIC);
    if(!t300rs){
        hid_err(hdev, "device entry could not be created\n");
        ret = -ENOMEM;
        goto t300rs_err;
    }

    t300rs->input_dev = input_dev;
    t300rs->hdev = hdev;
    t300rs->usbdev = usbdev;
    t300rs->usbif = usbif;
    t300rs->max_id = 0;
    t300rs->states = kmalloc(sizeof(struct t300rs_effect_state) * 0x60, GFP_ATOMIC);

    if(!t300rs->states){
        hid_err(hdev, "effect states could not be created\n");
        ret = -ENOMEM;
        goto states_err;
    }

    spin_lock_init(&t300rs->lock);

    drv_data->device_props = t300rs;

    report_list = &hdev->report_enum[HID_OUTPUT_REPORT].report_list;
    list_for_each_entry(report, report_list, list){
        int fieldnum;

        for(fieldnum = 0; fieldnum < report->maxfield; ++fieldnum){
            struct hid_field *field = report->field[fieldnum];

            if(field->maxusage <= 0){
                continue;
            }

            switch(field->usage[0].hid){
                case 0xff00000a:
                    if(field->report_count < 2){
                        hid_warn(hdev, "ignoring FF field with report_count < 2\n");
                        continue;
                    }

                    if(field->logical_maximum == field->logical_minimum){
                        hid_warn(hdev, "ignoring FF field with l_max == l_min");
                        continue;
                    }

                    if(t300rs->report && t300rs->report != report){
                        hid_warn(hdev, "ignoring FF field in other report\n");
                        continue;
                    }

                    if(t300rs->ff_field && t300rs->ff_field != field){
                        hid_warn(hdev, "ignoring duplicate FF field\n");
                        continue;
                    }

                    t300rs->report = report;
                    t300rs->ff_field = field;

                    for(i = 0; ff_bits[i] >= 0; ++i){
                        set_bit(ff_bits[i], input_dev->ffbit);
                    }

                    break;

                default:
                    hid_warn(hdev, "ignoring unknown output usage\n");
                    continue;
            }
        }
    }

    if(!t300rs->report){
        hid_err(hdev, "can't find FF field in output reports\n");
        ret = -ENODEV;
        goto out;
    }

    ret = input_ff_create(input_dev, T300RS_MAX_EFFECTS);
    if(ret){
        hid_err(hdev, "could not create input_ff\n");
        goto out;
    }

    ff = input_dev->ff;
    ff->upload = t300rs_upload;
    ff->playback = t300rs_play;
    ff->set_gain = t300rs_set_gain;
    ff->set_autocenter = t300rs_set_autocenter;
    ff->destroy = t300rs_destroy;

    t300rs->open = input_dev->open;
    t300rs->close = input_dev->close;

    input_dev->open = t300rs_open;
    input_dev->close = t300rs_close;

    ret = device_create_file(&hdev->dev, &dev_attr_range);
    if(ret){
        hid_warn(hdev, "unable to create sysfs interface for range\n");
        goto out;
    }
    

    hrtimer_init(&t300rs->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
    t300rs->hrtimer.function = t300rs_timer;
    
    spin_unlock_irqrestore(&lock, lock_flags);

    t300rs_range_store(dev, &dev_attr_range, range, 10);
    t300rs_set_gain(input_dev, 0xffff);

    hid_info(hdev, "force feedback for T300RS\n");
    return 0;

out:
    kfree(t300rs->states);
states_err:
    kfree(t300rs);
t300rs_err:
    kfree(drv_data);
err:
    hid_err(hdev, "failed creating force feedback device\n");
    return ret;

}

static int t300rs_probe(struct hid_device *hdev, const struct hid_device_id *id){
    int ret;
    struct t300rs_data *drv_data;

    spin_lock_init(&lock);
    spin_lock_irqsave(&lock, lock_flags);

    drv_data = kzalloc(sizeof(struct t300rs_data), GFP_ATOMIC);
    if(!drv_data){
        hid_err(hdev, "out of memory\n");
        ret = -ENOMEM;
        goto err;
    }

    drv_data->quirks = id->driver_data;
    hid_set_drvdata(hdev, (void*)drv_data);

    ret = hid_parse(hdev);
    if(ret){
        hid_err(hdev, "parse failed\n");
        goto err;
    }

    ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF);
    if(ret){
        hid_err(hdev, "hw start failed\n");
        goto err;
    }

    ret = t300rs_init(hdev, (void*)id->driver_data);
    if(ret){
        hid_err(hdev, "t300rs_init failed\n");
        goto err;
    }
    return 0;
err:
    kfree(drv_data);
    spin_unlock_irqrestore(&lock, lock_flags);
    return ret;
}

static void t300rs_remove(struct hid_device *hdev){
    struct t300rs_device_entry *t300rs;
    struct t300rs_data *drv_data;

    device_remove_file(&hdev->dev, &dev_attr_range);

    drv_data = hid_get_drvdata(hdev);
    t300rs = t300rs_get_device(hdev);

    hrtimer_cancel(&t300rs->hrtimer);

    hid_hw_stop(hdev);
    kfree(t300rs->states);
    kfree(drv_data);
    kfree(t300rs);

    return;
}

static __u8 *t300rs_report_fixup(struct hid_device *hdev, __u8 *rdesc, unsigned int *rsize){
    rdesc = t300rs_rdesc_fixed;
    *rsize = sizeof(t300rs_rdesc_fixed);
    return rdesc;
}

static const struct hid_device_id t300rs_devices[] = {
    {HID_USB_DEVICE(USB_VENDOR_ID_THRUSTMASTER, 0xb66e),
        .driver_data = (unsigned long)t300rs_ff_effects},
    {}
};
MODULE_DEVICE_TABLE(hid, t300rs_devices);

static struct hid_driver t300rs_driver = {
    .name = "t300rs",
    .id_table = t300rs_devices,
    .probe = t300rs_probe,
    .remove = t300rs_remove,
    .report_fixup = t300rs_report_fixup,
};
module_hid_driver(t300rs_driver);

MODULE_LICENSE("GPL");