/**
 * ir_input_register() - sets the IR keycode table and add the handlers
 *			    for keymap table get/set
 * @input_dev:	the struct input_dev descriptor of the device
 * @rc_tab:	the struct ir_scancode_table table of scancode/keymap
 *
 * This routine is used to initialize the input infrastructure to work with
 * an IR.
 * It should be called before registering the IR device.
 */
int ir_input_register(struct input_dev *input_dev,
		      struct ir_scancode_table *rc_tab)
{
	struct ir_input_dev *ir_dev;
	struct ir_scancode  *keymap    = rc_tab->scan;
	int i, rc;

	if (rc_tab->scan == NULL || !rc_tab->size)
		return -EINVAL;

	ir_dev = kzalloc(sizeof(*ir_dev), GFP_KERNEL);
	if (!ir_dev)
		return -ENOMEM;

	spin_lock_init(&rc_tab->lock);

	ir_dev->rc_tab.size = ir_roundup_tablesize(rc_tab->size);
	ir_dev->rc_tab.scan = kzalloc(ir_dev->rc_tab.size *
				    sizeof(struct ir_scancode), GFP_KERNEL);
	if (!ir_dev->rc_tab.scan)
		return -ENOMEM;

	IR_dprintk(1, "Allocated space for %d keycode entries (%zd bytes)\n",
		ir_dev->rc_tab.size,
		ir_dev->rc_tab.size * sizeof(ir_dev->rc_tab.scan));

	ir_copy_table(&ir_dev->rc_tab, rc_tab);

	/* set the bits for the keys */
	IR_dprintk(1, "key map size: %d\n", rc_tab->size);
	for (i = 0; i < rc_tab->size; i++) {
		IR_dprintk(1, "#%d: setting bit for keycode 0x%04x\n",
			i, keymap[i].keycode);
		set_bit(keymap[i].keycode, input_dev->keybit);
	}
	clear_bit(0, input_dev->keybit);

	set_bit(EV_KEY, input_dev->evbit);

	input_dev->getkeycode = ir_getkeycode;
	input_dev->setkeycode = ir_setkeycode;
	input_set_drvdata(input_dev, ir_dev);

	rc = input_register_device(input_dev);
	if (rc < 0) {
		kfree(rc_tab->scan);
		kfree(ir_dev);
		input_set_drvdata(input_dev, NULL);
	}

	return rc;
}

/**
 * ir_getkeycode() - get a keycode from the scancode->keycode table
 * @dev:	the struct input_dev device descriptor
 * @scancode:	the desired scancode
 * @keycode:	used to return the keycode, if found, or KEY_RESERVED
 * @return:	always returns zero.
 *
 * This routine is used to handle evdev EVIOCGKEY ioctl.
 */
static int ir_getkeycode(struct input_dev *dev,
			 unsigned int scancode, unsigned int *keycode)
{
	int start, end, mid;
	unsigned long flags;
	int key = KEY_RESERVED;
	struct ir_input_dev *ir_dev = input_get_drvdata(dev);
	struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;

	spin_lock_irqsave(&rc_tab->lock, flags);
	start = 0;
	end = rc_tab->len - 1;
	while (start <= end) {
		mid = (start + end) / 2;
		if (rc_tab->scan[mid].scancode < scancode)
			start = mid + 1;
		else if (rc_tab->scan[mid].scancode > scancode)
			end = mid - 1;
		else {
			key = rc_tab->scan[mid].keycode;
			break;
		}
	}
	spin_unlock_irqrestore(&rc_tab->lock, flags);

	if (key == KEY_RESERVED)
		IR_dprintk(1, "unknown key for scancode 0x%04x\n",
			   scancode);

	*keycode = key;
	return 0;
}

/**
 * ir_input_unregister() - unregisters IR and frees resources
 * @input_dev:	the struct input_dev descriptor of the device

 * This routine is used to free memory and de-register interfaces.
 */
void ir_input_unregister(struct input_dev *input_dev)
{
	struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
	struct ir_scancode_table *rc_tab;

	if (!ir_dev)
		return;

	IR_dprintk(1, "Freed keycode table\n");

	del_timer_sync(&ir_dev->timer_keyup);
	if (ir_dev->props)
		if (ir_dev->props->driver_type == RC_DRIVER_IR_RAW)
			ir_raw_event_unregister(input_dev);

	rc_tab = &ir_dev->rc_tab;
	rc_tab->size = 0;
	kfree(rc_tab->scan);
	rc_tab->scan = NULL;

	ir_unregister_class(input_dev);

	kfree(ir_dev->driver_name);
	kfree(ir_dev);
}

/**
 * store_protocol() - shows the current IR protocol
 * @d:		the device descriptor
 * @mattr:	the device attribute struct (unused)
 * @buf:	a pointer to the input buffer
 * @len:	length of the input buffer
 *
 * This routine is a callback routine for changing the IR protocol type.
 * it is trigged by reading /sys/class/irrcv/irrcv?/current_protocol.
 * It changes the IR the protocol name, if the IR type is recognized
 * by the driver.
 * If an unknown protocol name is used, returns -EINVAL.
 */
static ssize_t store_protocol(struct device *d,
			      struct device_attribute *mattr,
			      const char *data,
			      size_t len)
{
	struct ir_input_dev *ir_dev = dev_get_drvdata(d);
	u64 ir_type = IR_TYPE_UNKNOWN;
	int rc = -EINVAL;
	unsigned long flags;
	char *buf;

	buf = strsep((char **) &data, "\n");

	if (!strcasecmp(buf, "rc-5"))
		ir_type = IR_TYPE_RC5;
	else if (!strcasecmp(buf, "pd"))
		ir_type = IR_TYPE_PD;
	else if (!strcasecmp(buf, "nec"))
		ir_type = IR_TYPE_NEC;

	if (ir_type == IR_TYPE_UNKNOWN) {
		IR_dprintk(1, "Error setting protocol to %lld\n",
			   (long long)ir_type);
		return -EINVAL;
	}

	if (ir_dev->props && ir_dev->props->change_protocol)
		rc = ir_dev->props->change_protocol(ir_dev->props->priv,
						    ir_type);

	if (rc < 0) {
		IR_dprintk(1, "Error setting protocol to %lld\n",
			   (long long)ir_type);
		return -EINVAL;
	}

	spin_lock_irqsave(&ir_dev->rc_tab.lock, flags);
	ir_dev->rc_tab.ir_type = ir_type;
	spin_unlock_irqrestore(&ir_dev->rc_tab.lock, flags);

	IR_dprintk(1, "Current protocol is %lld\n",
		   (long long)ir_type);

	return len;
}

/**
 * ir_keyup() - generates input event to cleanup a key press
 * @ir:         the struct ir_input_dev descriptor of the device
 *
 * This routine is used to signal that a key has been released on the
 * remote control. It reports a keyup input event via input_report_key().
 */
static void ir_keyup(struct ir_input_dev *ir)
{
	if (!ir->keypressed)
		return;

	IR_dprintk(1, "keyup key 0x%04x\n", ir->last_keycode);
	input_report_key(ir->input_dev, ir->last_keycode, 0);
	input_sync(ir->input_dev);
	ir->keypressed = false;
}

/**
 * ir_g_keycode_from_table() - gets the keycode that corresponds to a scancode
 * @input_dev:	the struct input_dev descriptor of the device
 * @scancode:	the scancode that we're seeking
 *
 * This routine is used by the input routines when a key is pressed at the
 * IR. The scancode is received and needs to be converted into a keycode.
 * If the key is not found, it returns KEY_RESERVED. Otherwise, returns the
 * corresponding keycode from the table.
 */
u32 ir_g_keycode_from_table(struct input_dev *dev, u32 scancode)
{
	int keycode;

	ir_getkeycode(dev, scancode, &keycode);
	if (keycode != KEY_RESERVED)
		IR_dprintk(1, "%s: scancode 0x%04x keycode 0x%02x\n",
			   dev->name, scancode, keycode);
	return keycode;
}

void ir_raw_event_set_idle(struct input_dev *input_dev, int idle)
{
	struct ir_input_dev *ir = input_get_drvdata(input_dev);
	struct ir_raw_event_ctrl *raw = ir->raw;
	ktime_t now;
	u64 delta;

	if (!ir->props)
		return;

	if (!ir->raw)
		goto out;

	if (idle) {
		IR_dprintk(2, "enter idle mode\n");
		raw->last_event = ktime_get();
	} else {
		IR_dprintk(2, "exit idle mode\n");

		now = ktime_get();
		delta = ktime_to_ns(ktime_sub(now, ir->raw->last_event));

		WARN_ON(raw->this_ev.pulse);

		raw->this_ev.duration =
			min(raw->this_ev.duration + delta,
						(u64)IR_MAX_DURATION);

		ir_raw_event_store(input_dev, &raw->this_ev);

		if (raw->this_ev.duration == IR_MAX_DURATION)
			ir_raw_event_reset(input_dev);

		raw->this_ev.duration = 0;
	}
out:
	if (ir->props->s_idle)
		ir->props->s_idle(ir->props->priv, idle);
	ir->idle = idle;
}

/**
 * ir_raw_event_store() - pass a pulse/space duration to the raw ir decoders
 * @dev:	the struct rc_dev device descriptor
 * @ev:		the struct ir_raw_event descriptor of the pulse/space
 *
 * This routine (which may be called from an interrupt context) stores a
 * pulse/space duration for the raw ir decoding state machines. Pulses are
 * signalled as positive values and spaces as negative values. A zero value
 * will reset the decoding state machines.
 */
int ir_raw_event_store(struct rc_dev *dev, struct ir_raw_event *ev)
{
	if (!dev->raw)
		return -EINVAL;

	IR_dprintk(2, "sample: (%05dus %s)\n",
		   TO_US(ev->duration), TO_STR(ev->pulse));

	if (kfifo_in(&dev->raw->kfifo, ev, sizeof(*ev)) != sizeof(*ev))
		return -ENOMEM;

	return 0;
}

/**
 * ir_resize_table() - resizes a scancode table if necessary
 * @rc_tab:	the ir_scancode_table to resize
 * @return:	zero on success or a negative error code
 *
 * This routine will shrink the ir_scancode_table if it has lots of
 * unused entries and grow it if it is full.
 */
static int ir_resize_table(struct ir_scancode_table *rc_tab)
{
	unsigned int oldalloc = rc_tab->alloc;
	unsigned int newalloc = oldalloc;
	struct ir_scancode *oldscan = rc_tab->scan;
	struct ir_scancode *newscan;

	if (rc_tab->size == rc_tab->len) {
		/* All entries in use -> grow keytable */
		if (rc_tab->alloc >= IR_TAB_MAX_SIZE)
			return -ENOMEM;

		newalloc *= 2;
		IR_dprintk(1, "Growing table to %u bytes\n", newalloc);
	}

	if ((rc_tab->len * 3 < rc_tab->size) && (oldalloc > IR_TAB_MIN_SIZE)) {
		/* Less than 1/3 of entries in use -> shrink keytable */
		newalloc /= 2;
		IR_dprintk(1, "Shrinking table to %u bytes\n", newalloc);
	}

	if (newalloc == oldalloc)
		return 0;

	newscan = kmalloc(newalloc, GFP_ATOMIC);
	if (!newscan) {
		IR_dprintk(1, "Failed to kmalloc %u bytes\n", newalloc);
		return -ENOMEM;
	}

	memcpy(newscan, rc_tab->scan, rc_tab->len * sizeof(struct ir_scancode));
	rc_tab->scan = newscan;
	rc_tab->alloc = newalloc;
	rc_tab->size = rc_tab->alloc / sizeof(struct ir_scancode);
	kfree(oldscan);
	return 0;
}

/**
 * ir_raw_event_store() - pass a pulse/space duration to the raw ir decoders
 * @dev:	the struct rc_dev device descriptor
 * @ev:		the struct ir_raw_event descriptor of the pulse/space
 *
 * This routine (which may be called from an interrupt context) stores a
 * pulse/space duration for the raw ir decoding state machines. Pulses are
 * signalled as positive values and spaces as negative values. A zero value
 * will reset the decoding state machines.
 */
int ir_raw_event_store(struct rc_dev *dev, struct ir_raw_event *ev)
{
	if (!dev->raw)
		return -EINVAL;

	IR_dprintk(2, "sample: (%05dus %s)\n",
		   TO_US(ev->duration), TO_STR(ev->pulse));

	if (!kfifo_put(&dev->raw->kfifo, *ev)) {
		dev_err(&dev->dev, "IR event FIFO is full!\n");
		return -ENOSPC;
	}

	return 0;
}

/**
 * ir_raw_event_store() - pass a pulse/space duration to the raw ir decoders
 * @input_dev:	the struct input_dev device descriptor
 * @ev:		the struct ir_raw_event descriptor of the pulse/space
 *
 * This routine (which may be called from an interrupt context) stores a
 * pulse/space duration for the raw ir decoding state machines. Pulses are
 * signalled as positive values and spaces as negative values. A zero value
 * will reset the decoding state machines.
 */
int ir_raw_event_store(struct input_dev *input_dev, struct ir_raw_event *ev)
{
	struct ir_input_dev *ir = input_get_drvdata(input_dev);

	if (!ir->raw)
		return -EINVAL;

	IR_dprintk(2, "sample: (05%dus %s)\n",
		TO_US(ev->duration), TO_STR(ev->pulse));

	if (kfifo_in(&ir->raw->kfifo, ev, sizeof(*ev)) != sizeof(*ev))
		return -ENOMEM;

	return 0;
}

static void mce_kbd_rx_timeout(unsigned long data)
{
	struct mce_kbd_dec *mce_kbd = (struct mce_kbd_dec *)data;
	int i;
	unsigned char maskcode;

	IR_dprintk(2, "timer callback clearing all keys\n");

	for (i = 0; i < 7; i++) {
		maskcode = kbd_keycodes[MCIR2_MASK_KEYS_START + i];
		input_report_key(mce_kbd->idev, maskcode, 0);
	}

	for (i = 0; i < MCIR2_MASK_KEYS_START; i++)
		input_report_key(mce_kbd->idev, kbd_keycodes[i], 0);
}

void ir_input_unregister(struct input_dev *dev)
{
	struct ir_input_dev *ir_dev = input_get_drvdata(dev);
	struct ir_scancode_table *rc_tab;

	if (!ir_dev)
		return;

	IR_dprintk(1, "Freed keycode table\n");

	rc_tab = &ir_dev->rc_tab;
	rc_tab->size = 0;
	kfree(rc_tab->scan);
	rc_tab->scan = NULL;

	kfree(ir_dev);
	input_unregister_device(dev);
}

/**
 * ir_raw_event_set_idle() - provide hint to rc-core when the device is idle or not
 * @dev:	the struct rc_dev device descriptor
 * @idle:	whether the device is idle or not
 */
void ir_raw_event_set_idle(struct rc_dev *dev, bool idle)
{
	if (!dev->raw)
		return;

	IR_dprintk(2, "%s idle mode\n", idle ? "enter" : "leave");

	if (idle) {
		dev->raw->this_ev.timeout = true;
		ir_raw_event_store(dev, &dev->raw->this_ev);
		init_ir_raw_event(&dev->raw->this_ev);
	}

	if (dev->s_idle)
		dev->s_idle(dev, idle);

	dev->idle = idle;
}

int ir_copy_table(struct ir_scancode_table *destin,
		 const struct ir_scancode_table *origin)
{
	int i, j = 0;

	for (i = 0; i < origin->size; i++) {
		if (origin->scan[i].keycode == KEY_UNKNOWN ||
		   origin->scan[i].keycode == KEY_RESERVED)
			continue;

		memcpy(&destin->scan[j], &origin->scan[i], sizeof(struct ir_scancode));
		j++;
	}
	destin->size = j;

	IR_dprintk(1, "Copied %d scancodes to the new keycode table\n", destin->size);

	return 0;
}

/**
 * ir_keydown() - generates input event for a key press
 * @dev:        the struct input_dev descriptor of the device
 * @scancode:   the scancode that we're seeking
 * @toggle:     the toggle value (protocol dependent, if the protocol doesn't
 *              support toggle values, this should be set to zero)
 *
 * This routine is used by the input routines when a key is pressed at the
 * IR. It gets the keycode for a scancode and reports an input event via
 * input_report_key().
 */
void ir_keydown(struct input_dev *dev, int scancode, u8 toggle)
{
	unsigned long flags;
	struct ir_input_dev *ir = input_get_drvdata(dev);

	u32 keycode = ir_g_keycode_from_table(dev, scancode);

	spin_lock_irqsave(&ir->keylock, flags);

	input_event(dev, EV_MSC, MSC_SCAN, scancode);

	/* Repeat event? */
	if (ir->keypressed &&
	    ir->last_scancode == scancode &&
	    ir->last_toggle == toggle)
		goto set_timer;

	/* Release old keypress */
	ir_keyup(ir);

	ir->last_scancode = scancode;
	ir->last_toggle = toggle;
	ir->last_keycode = keycode;


	if (keycode == KEY_RESERVED)
		goto out;


	/* Register a keypress */
	ir->keypressed = true;
	IR_dprintk(1, "%s: key down event, key 0x%04x, scancode 0x%04x\n",
		   dev->name, keycode, scancode);
	input_report_key(dev, ir->last_keycode, 1);
	input_sync(dev);

set_timer:
	ir->keyup_jiffies = jiffies + msecs_to_jiffies(IR_KEYPRESS_TIMEOUT);
	mod_timer(&ir->timer_keyup, ir->keyup_jiffies);
out:
	spin_unlock_irqrestore(&ir->keylock, flags);
}

/**
 * ir_g_keycode_from_table() - gets the keycode that corresponds to a scancode
 * @input_dev:	the struct input_dev descriptor of the device
 * @scancode:	the scancode that we're seeking
 *
 * This routine is used by the input routines when a key is pressed at the
 * IR. The scancode is received and needs to be converted into a keycode.
 * If the key is not found, it returns KEY_UNKNOWN. Otherwise, returns the
 * corresponding keycode from the table.
 */
u32 ir_g_keycode_from_table(struct input_dev *dev, u32 scancode)
{
	struct ir_input_dev *ir_dev = input_get_drvdata(dev);
	struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;
	struct ir_scancode *keymap = rc_tab->scan;
	int elem;

	elem = ir_seek_table(rc_tab, scancode);
	if (elem >= 0) {
		IR_dprintk(1, "%s: scancode 0x%04x keycode 0x%02x\n",
			   dev->name, scancode, keymap[elem].keycode);

		return rc_tab->scan[elem].keycode;
	}

	printk(KERN_INFO "%s: unknown key for scancode 0x%04x\n",
	       dev->name, scancode);

	/* Reports userspace that an unknown keycode were got */
	return KEY_RESERVED;
}

/**
 * ir_raw_event_set_idle() - provide hint to rc-core when the device is idle or not
 * @dev:	the struct rc_dev device descriptor
 * @idle:	whether the device is idle or not
 */
void ir_raw_event_set_idle(struct rc_dev *dev, bool idle)
{
	if (!dev->raw)
		return;

#ifdef CONFIG_DEBUG_PRINTK
	IR_dprintk(2, "%s idle mode\n", idle ? "enter" : "leave");
#else
	IR_d;
#endif

	if (idle) {
		dev->raw->this_ev.timeout = true;
		ir_raw_event_store(dev, &dev->raw->this_ev);
		init_ir_raw_event(&dev->raw->this_ev);
	}

	if (dev->s_idle)
		dev->s_idle(dev, idle);

	dev->idle = idle;
}

/**
 * show_protocol() - shows the current IR protocol
 * @d:		the device descriptor
 * @mattr:	the device attribute struct (unused)
 * @buf:	a pointer to the output buffer
 *
 * This routine is a callback routine for input read the IR protocol type.
 * it is trigged by reading /sys/class/irrcv/irrcv?/current_protocol.
 * It returns the protocol name, as understood by the driver.
 */
static ssize_t show_protocol(struct device *d,
			     struct device_attribute *mattr, char *buf)
{
	char *s;
	struct ir_input_dev *ir_dev = dev_get_drvdata(d);
	u64 ir_type = ir_dev->rc_tab.ir_type;

	IR_dprintk(1, "Current protocol is %lld\n", (long long)ir_type);

	/* FIXME: doesn't support multiple protocols at the same time */
	if (ir_type == IR_TYPE_UNKNOWN)
		s = "Unknown";
	else if (ir_type == IR_TYPE_RC5)
		s = "RC-5";
	else if (ir_type == IR_TYPE_PD)
		s = "Pulse/distance";
	else if (ir_type == IR_TYPE_NEC)
		s = "NEC";
	else
		s = "Other";

	return sprintf(buf, "%s\n", s);
}

/**
 * ir_insert_key() - insert a keycode at the table
 * @rc_tab:		keycode table
 * @scancode:	the desired scancode
 * @keycode:	the keycode to be retorned.
 *
 */
static int ir_insert_key(struct ir_scancode_table *rc_tab,
			  int scancode, int keycode)
{
	unsigned long flags;
	int elem = rc_tab->size;
	int newsize = rc_tab->size + 1;
	int resize = ir_is_resize_needed(rc_tab, newsize);
	struct ir_scancode *oldkeymap = rc_tab->scan;
	struct ir_scancode *newkeymap;

	if (resize) {
		newkeymap = kzalloc(ir_roundup_tablesize(newsize) *
				    sizeof(*newkeymap), GFP_ATOMIC);
		if (!newkeymap)
			return -ENOMEM;

		memcpy(newkeymap, oldkeymap,
		       rc_tab->size * sizeof(*newkeymap));
	} else
		newkeymap  = oldkeymap;

	/* Stores the new code at the table */
	IR_dprintk(1, "#%d: New scan 0x%04x with key 0x%04x\n",
		   rc_tab->size, scancode, keycode);

	spin_lock_irqsave(&rc_tab->lock, flags);
	rc_tab->size = newsize;
	if (resize) {
		rc_tab->scan = newkeymap;
		kfree(oldkeymap);
	}
	newkeymap[elem].scancode = scancode;
	newkeymap[elem].keycode  = keycode;
	spin_unlock_irqrestore(&rc_tab->lock, flags);

	return 0;
}