Merge branch 'next' into for-linus

Conflicts:
	include/linux/input.h

48 files changed, 2690 insertions, 610 deletions

diff --git a/drivers/input/Makefile b/drivers/input/Makefile
index 7ad212d31f99..09614ce74961 100644
--- a/drivers/input/Makefile
+++ b/drivers/input/Makefile
@@ -5,7 +5,7 @@
 # Each configuration option enables a list of files.
 
 obj-$(CONFIG_INPUT)		+= input-core.o
-input-core-objs := input.o input-compat.o ff-core.o
+input-core-y := input.o input-compat.o input-mt.o ff-core.o
 
 obj-$(CONFIG_INPUT_FF_MEMLESS)	+= ff-memless.o
 obj-$(CONFIG_INPUT_POLLDEV)	+= input-polldev.o
diff --git a/drivers/input/apm-power.c b/drivers/input/apm-power.c
index 7d61a9660806..e90ee3d30613 100644
--- a/drivers/input/apm-power.c
+++ b/drivers/input/apm-power.c
@@ -9,6 +9,8 @@
  *
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/module.h>
 #include <linux/input.h>
 #include <linux/slab.h>
@@ -23,8 +25,7 @@ static void system_power_event(unsigned int keycode)
 	switch (keycode) {
 	case KEY_SUSPEND:
 		apm_queue_event(APM_USER_SUSPEND);
-
-		printk(KERN_INFO "apm-power: Requesting system suspend...\n");
+		pr_info("Requesting system suspend...\n");
 		break;
 	default:
 		break;
@@ -65,18 +66,15 @@ static int apmpower_connect(struct input_handler *handler,
 
 	error = input_register_handle(handle);
 	if (error) {
-		printk(KERN_ERR
-			"apm-power: Failed to register input power handler, "
-			"error %d\n", error);
+		pr_err("Failed to register input power handler, error %d\n",
+		       error);
 		kfree(handle);
 		return error;
 	}
 
 	error = input_open_device(handle);
 	if (error) {
-		printk(KERN_ERR
-			"apm-power: Failed to open input power device, "
-			"error %d\n", error);
+		pr_err("Failed to open input power device, error %d\n", error);
 		input_unregister_handle(handle);
 		kfree(handle);
 		return error;
diff --git a/drivers/input/evbug.c b/drivers/input/evbug.c
index f7c5c14ec12a..cd4e6679d61a 100644
--- a/drivers/input/evbug.c
+++ b/drivers/input/evbug.c
@@ -26,6 +26,8 @@
  * Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/input.h>
@@ -38,8 +40,8 @@ MODULE_LICENSE("GPL");
 
 static void evbug_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
 {
-	printk(KERN_DEBUG "evbug.c: Event. Dev: %s, Type: %d, Code: %d, Value: %d\n",
-		dev_name(&handle->dev->dev), type, code, value);
+	printk(KERN_DEBUG pr_fmt("Event. Dev: %s, Type: %d, Code: %d, Value: %d\n"),
+	       dev_name(&handle->dev->dev), type, code, value);
 }
 
 static int evbug_connect(struct input_handler *handler, struct input_dev *dev,
@@ -64,10 +66,10 @@ static int evbug_connect(struct input_handler *handler, struct input_dev *dev,
 	if (error)
 		goto err_unregister_handle;
 
-	printk(KERN_DEBUG "evbug.c: Connected device: %s (%s at %s)\n",
-		dev_name(&dev->dev),
-		dev->name ?: "unknown",
-		dev->phys ?: "unknown");
+	printk(KERN_DEBUG pr_fmt("Connected device: %s (%s at %s)\n"),
+	       dev_name(&dev->dev),
+	       dev->name ?: "unknown",
+	       dev->phys ?: "unknown");
 
 	return 0;
 
@@ -80,8 +82,8 @@ static int evbug_connect(struct input_handler *handler, struct input_dev *dev,
 
 static void evbug_disconnect(struct input_handle *handle)
 {
-	printk(KERN_DEBUG "evbug.c: Disconnected device: %s\n",
-		dev_name(&handle->dev->dev));
+	printk(KERN_DEBUG pr_fmt("Disconnected device: %s\n"),
+	       dev_name(&handle->dev->dev));
 
 	input_close_device(handle);
 	input_unregister_handle(handle);
diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
index 68f09a868434..c8471a2552e7 100644
--- a/drivers/input/evdev.c
+++ b/drivers/input/evdev.c
@@ -8,6 +8,8 @@
  * the Free Software Foundation.
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #define EVDEV_MINOR_BASE	64
 #define EVDEV_MINORS		32
 #define EVDEV_MIN_BUFFER_SIZE	64U
@@ -522,12 +524,11 @@ static int handle_eviocgbit(struct input_dev *dev,
 	if (type == EV_KEY && size == OLD_KEY_MAX) {
 		len = OLD_KEY_MAX;
 		if (printk_timed_ratelimit(&keymax_warn_time, 10 * 1000))
-			printk(KERN_WARNING
-				"evdev.c(EVIOCGBIT): Suspicious buffer size %u, "
-				"limiting output to %zu bytes. See "
-				"http://userweb.kernel.org/~dtor/eviocgbit-bug.html\n",
-				OLD_KEY_MAX,
-				BITS_TO_LONGS(OLD_KEY_MAX) * sizeof(long));
+			pr_warning("(EVIOCGBIT): Suspicious buffer size %u, "
+				   "limiting output to %zu bytes. See "
+				   "http://userweb.kernel.org/~dtor/eviocgbit-bug.html\n",
+				   OLD_KEY_MAX,
+				   BITS_TO_LONGS(OLD_KEY_MAX) * sizeof(long));
 	}
 
 	return bits_to_user(bits, len, size, p, compat_mode);
@@ -686,6 +687,10 @@ static long evdev_do_ioctl(struct file *file, unsigned int cmd,
 #define EVIOC_MASK_SIZE(nr)	((nr) & ~(_IOC_SIZEMASK << _IOC_SIZESHIFT))
 	switch (EVIOC_MASK_SIZE(cmd)) {
 
+	case EVIOCGPROP(0):
+		return bits_to_user(dev->propbit, INPUT_PROP_MAX,
+				    size, p, compat_mode);
+
 	case EVIOCGKEY(0):
 		return bits_to_user(dev->key, KEY_MAX, size, p, compat_mode);
 
@@ -897,7 +902,7 @@ static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
 			break;
 
 	if (minor == EVDEV_MINORS) {
-		printk(KERN_ERR "evdev: no more free evdev devices\n");
+		pr_err("no more free evdev devices\n");
 		return -ENFILE;
 	}
 
diff --git a/drivers/input/ff-core.c b/drivers/input/ff-core.c
index 03078c08309a..3367f760d75a 100644
--- a/drivers/input/ff-core.c
+++ b/drivers/input/ff-core.c
@@ -23,7 +23,7 @@
 
 /* #define DEBUG */
 
-#define debug(format, arg...) pr_debug("ff-core: " format "\n", ## arg)
+#define pr_fmt(fmt) KBUILD_BASENAME ": " fmt
 
 #include <linux/input.h>
 #include <linux/module.h>
@@ -116,7 +116,7 @@ int input_ff_upload(struct input_dev *dev, struct ff_effect *effect,
 
 	if (effect->type < FF_EFFECT_MIN || effect->type > FF_EFFECT_MAX ||
 	    !test_bit(effect->type, dev->ffbit)) {
-		debug("invalid or not supported effect type in upload");
+		pr_debug("invalid or not supported effect type in upload\n");
 		return -EINVAL;
 	}
 
@@ -124,7 +124,7 @@ int input_ff_upload(struct input_dev *dev, struct ff_effect *effect,
 	    (effect->u.periodic.waveform < FF_WAVEFORM_MIN ||
 	     effect->u.periodic.waveform > FF_WAVEFORM_MAX ||
 	     !test_bit(effect->u.periodic.waveform, dev->ffbit))) {
-		debug("invalid or not supported wave form in upload");
+		pr_debug("invalid or not supported wave form in upload\n");
 		return -EINVAL;
 	}
 
@@ -246,7 +246,7 @@ static int flush_effects(struct input_dev *dev, struct file *file)
 	struct ff_device *ff = dev->ff;
 	int i;
 
-	debug("flushing now");
+	pr_debug("flushing now\n");
 
 	mutex_lock(&ff->mutex);
 
@@ -315,8 +315,7 @@ int input_ff_create(struct input_dev *dev, int max_effects)
 	int i;
 
 	if (!max_effects) {
-		printk(KERN_ERR
-		       "ff-core: cannot allocate device without any effects\n");
+		pr_err("cannot allocate device without any effects\n");
 		return -EINVAL;
 	}
 
diff --git a/drivers/input/ff-memless.c b/drivers/input/ff-memless.c
index 1d881c96ba8f..117a59aaa70e 100644
--- a/drivers/input/ff-memless.c
+++ b/drivers/input/ff-memless.c
@@ -23,7 +23,7 @@
 
 /* #define DEBUG */
 
-#define debug(format, arg...) pr_debug("ff-memless: " format "\n", ## arg)
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/slab.h>
 #include <linux/input.h>
@@ -129,7 +129,7 @@ static void ml_schedule_timer(struct ml_device *ml)
 	int events = 0;
 	int i;
 
-	debug("calculating next timer");
+	pr_debug("calculating next timer\n");
 
 	for (i = 0; i < FF_MEMLESS_EFFECTS; i++) {
 
@@ -149,10 +149,10 @@ static void ml_schedule_timer(struct ml_device *ml)
 	}
 
 	if (!events) {
-		debug("no actions");
+		pr_debug("no actions\n");
 		del_timer(&ml->timer);
 	} else {
-		debug("timer set");
+		pr_debug("timer set\n");
 		mod_timer(&ml->timer, earliest);
 	}
 }
@@ -173,8 +173,8 @@ static int apply_envelope(struct ml_effect_state *state, int value,
 	if (envelope->attack_length &&
 	    time_before(now,
 			state->play_at + msecs_to_jiffies(envelope->attack_length))) {
-		debug("value = 0x%x, attack_level = 0x%x", value,
-		      envelope->attack_level);
+		pr_debug("value = 0x%x, attack_level = 0x%x\n",
+			 value, envelope->attack_level);
 		time_from_level = jiffies_to_msecs(now - state->play_at);
 		time_of_envelope = envelope->attack_length;
 		envelope_level = min_t(__s16, envelope->attack_level, 0x7fff);
@@ -191,13 +191,13 @@ static int apply_envelope(struct ml_effect_state *state, int value,
 
 	difference = abs(value) - envelope_level;
 
-	debug("difference = %d", difference);
-	debug("time_from_level = 0x%x", time_from_level);
-	debug("time_of_envelope = 0x%x", time_of_envelope);
+	pr_debug("difference = %d\n", difference);
+	pr_debug("time_from_level = 0x%x\n", time_from_level);
+	pr_debug("time_of_envelope = 0x%x\n", time_of_envelope);
 
 	difference = difference * time_from_level / time_of_envelope;
 
-	debug("difference = %d", difference);
+	pr_debug("difference = %d\n", difference);
 
 	return value < 0 ?
 		-(difference + envelope_level) : (difference + envelope_level);
@@ -215,8 +215,7 @@ static int get_compatible_type(struct ff_device *ff, int effect_type)
 	if (effect_type == FF_PERIODIC && test_bit(FF_RUMBLE, ff->ffbit))
 		return FF_RUMBLE;
 
-	printk(KERN_ERR
-	       "ff-memless: invalid type in get_compatible_type()\n");
+	pr_err("invalid type in get_compatible_type()\n");
 
 	return 0;
 }
@@ -312,7 +311,7 @@ static void ml_combine_effects(struct ff_effect *effect,
 		break;
 
 	default:
-		printk(KERN_ERR "ff-memless: invalid type in ml_combine_effects()\n");
+		pr_err("invalid type in ml_combine_effects()\n");
 		break;
 	}
 
@@ -406,7 +405,7 @@ static void ml_effect_timer(unsigned long timer_data)
 	struct ml_device *ml = dev->ff->private;
 	unsigned long flags;
 
-	debug("timer: updating effects");
+	pr_debug("timer: updating effects\n");
 
 	spin_lock_irqsave(&dev->event_lock, flags);
 	ml_play_effects(ml);
@@ -438,7 +437,7 @@ static int ml_ff_playback(struct input_dev *dev, int effect_id, int value)
 	struct ml_effect_state *state = &ml->states[effect_id];
 
 	if (value > 0) {
-		debug("initiated play");
+		pr_debug("initiated play\n");
 
 		__set_bit(FF_EFFECT_STARTED, &state->flags);
 		state->count = value;
@@ -449,7 +448,7 @@ static int ml_ff_playback(struct input_dev *dev, int effect_id, int value)
 		state->adj_at = state->play_at;
 
 	} else {
-		debug("initiated stop");
+		pr_debug("initiated stop\n");
 
 		if (test_bit(FF_EFFECT_PLAYING, &state->flags))
 			__set_bit(FF_EFFECT_ABORTING, &state->flags);
diff --git a/drivers/input/gameport/gameport.c b/drivers/input/gameport/gameport.c
index 46239e47a260..dbf741c95835 100644
--- a/drivers/input/gameport/gameport.c
+++ b/drivers/input/gameport/gameport.c
@@ -18,13 +18,11 @@
 #include <linux/ioport.h>
 #include <linux/init.h>
 #include <linux/gameport.h>
-#include <linux/wait.h>
 #include <linux/slab.h>
 #include <linux/delay.h>
-#include <linux/kthread.h>
+#include <linux/workqueue.h>
 #include <linux/sched.h>	/* HZ */
 #include <linux/mutex.h>
-#include <linux/freezer.h>
 
 /*#include <asm/io.h>*/
 
@@ -234,58 +232,22 @@ struct gameport_event {
 
 static DEFINE_SPINLOCK(gameport_event_lock);	/* protects gameport_event_list */
 static LIST_HEAD(gameport_event_list);
-static DECLARE_WAIT_QUEUE_HEAD(gameport_wait);
-static struct task_struct *gameport_task;
 
-static int gameport_queue_event(void *object, struct module *owner,
-				enum gameport_event_type event_type)
+static struct gameport_event *gameport_get_event(void)
 {
+	struct gameport_event *event = NULL;
 	unsigned long flags;
-	struct gameport_event *event;
-	int retval = 0;
 
 	spin_lock_irqsave(&gameport_event_lock, flags);
 
-	/*
-	 * Scan event list for the other events for the same gameport port,
-	 * starting with the most recent one. If event is the same we
-	 * do not need add new one. If event is of different type we
-	 * need to add this event and should not look further because
-	 * we need to preseve sequence of distinct events.
-	 */
-	list_for_each_entry_reverse(event, &gameport_event_list, node) {
-		if (event->object == object) {
-			if (event->type == event_type)
-				goto out;
-			break;
-		}
-	}
-
-	event = kmalloc(sizeof(struct gameport_event), GFP_ATOMIC);
-	if (!event) {
-		pr_err("Not enough memory to queue event %d\n", event_type);
-		retval = -ENOMEM;
-		goto out;
-	}
-
-	if (!try_module_get(owner)) {
-		pr_warning("Can't get module reference, dropping event %d\n",
-			   event_type);
-		kfree(event);
-		retval = -EINVAL;
-		goto out;
+	if (!list_empty(&gameport_event_list)) {
+		event = list_first_entry(&gameport_event_list,
+					 struct gameport_event, node);
+		list_del_init(&event->node);
 	}
 
-	event->type = event_type;
-	event->object = object;
-	event->owner = owner;
-
-	list_add_tail(&event->node, &gameport_event_list);
-	wake_up(&gameport_wait);
-
-out:
 	spin_unlock_irqrestore(&gameport_event_lock, flags);
-	return retval;
+	return event;
 }
 
 static void gameport_free_event(struct gameport_event *event)
@@ -319,24 +281,8 @@ static void gameport_remove_duplicate_events(struct gameport_event *event)
 	spin_unlock_irqrestore(&gameport_event_lock, flags);
 }
 
-static struct gameport_event *gameport_get_event(void)
-{
-	struct gameport_event *event = NULL;
-	unsigned long flags;
-
-	spin_lock_irqsave(&gameport_event_lock, flags);
-
-	if (!list_empty(&gameport_event_list)) {
-		event = list_first_entry(&gameport_event_list,
-					 struct gameport_event, node);
-		list_del_init(&event->node);
-	}
-
-	spin_unlock_irqrestore(&gameport_event_lock, flags);
-	return event;
-}
 
-static void gameport_handle_event(void)
+static void gameport_handle_events(struct work_struct *work)
 {
 	struct gameport_event *event;
 
@@ -368,6 +314,59 @@ static void gameport_handle_event(void)
 	mutex_unlock(&gameport_mutex);
 }
 
+static DECLARE_WORK(gameport_event_work, gameport_handle_events);
+
+static int gameport_queue_event(void *object, struct module *owner,
+				enum gameport_event_type event_type)
+{
+	unsigned long flags;
+	struct gameport_event *event;
+	int retval = 0;
+
+	spin_lock_irqsave(&gameport_event_lock, flags);
+
+	/*
+	 * Scan event list for the other events for the same gameport port,
+	 * starting with the most recent one. If event is the same we
+	 * do not need add new one. If event is of different type we
+	 * need to add this event and should not look further because
+	 * we need to preserve sequence of distinct events.
+	 */
+	list_for_each_entry_reverse(event, &gameport_event_list, node) {
+		if (event->object == object) {
+			if (event->type == event_type)
+				goto out;
+			break;
+		}
+	}
+
+	event = kmalloc(sizeof(struct gameport_event), GFP_ATOMIC);
+	if (!event) {
+		pr_err("Not enough memory to queue event %d\n", event_type);
+		retval = -ENOMEM;
+		goto out;
+	}
+
+	if (!try_module_get(owner)) {
+		pr_warning("Can't get module reference, dropping event %d\n",
+			   event_type);
+		kfree(event);
+		retval = -EINVAL;
+		goto out;
+	}
+
+	event->type = event_type;
+	event->object = object;
+	event->owner = owner;
+
+	list_add_tail(&event->node, &gameport_event_list);
+	schedule_work(&gameport_event_work);
+
+out:
+	spin_unlock_irqrestore(&gameport_event_lock, flags);
+	return retval;
+}
+
 /*
  * Remove all events that have been submitted for a given object,
  * be it a gameport port or a driver.
@@ -419,19 +418,6 @@ static struct gameport *gameport_get_pending_child(struct gameport *parent)
 	return child;
 }
 
-static int gameport_thread(void *nothing)
-{
-	set_freezable();
-	do {
-		gameport_handle_event();
-		wait_event_freezable(gameport_wait,
-			kthread_should_stop() || !list_empty(&gameport_event_list));
-	} while (!kthread_should_stop());
-
-	return 0;
-}
-
-
 /*
  * Gameport port operations
  */
@@ -814,13 +800,6 @@ static int __init gameport_init(void)
 		return error;
 	}
 
-	gameport_task = kthread_run(gameport_thread, NULL, "kgameportd");
-	if (IS_ERR(gameport_task)) {
-		bus_unregister(&gameport_bus);
-		error = PTR_ERR(gameport_task);
-		pr_err("Failed to start kgameportd, error: %d\n", error);
-		return error;
-	}
 
 	return 0;
 }
@@ -828,7 +807,12 @@ static int __init gameport_init(void)
 static void __exit gameport_exit(void)
 {
 	bus_unregister(&gameport_bus);
-	kthread_stop(gameport_task);
+
+	/*
+	 * There should not be any outstanding events but work may
+	 * still be scheduled so simply cancel it.
+	 */
+	cancel_work_sync(&gameport_event_work);
 }
 
 subsys_initcall(gameport_init);
diff --git a/drivers/input/input-mt.c b/drivers/input/input-mt.c
new file mode 100644
index 000000000000..c48c81f0308d
--- /dev/null
+++ b/drivers/input/input-mt.c
@@ -0,0 +1,170 @@
+/*
+ * Input Multitouch Library
+ *
+ * Copyright (c) 2008-2010 Henrik Rydberg
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ */
+
+#include <linux/input/mt.h>
+#include <linux/slab.h>
+
+#define TRKID_SGN	((TRKID_MAX + 1) >> 1)
+
+/**
+ * input_mt_init_slots() - initialize MT input slots
+ * @dev: input device supporting MT events and finger tracking
+ * @num_slots: number of slots used by the device
+ *
+ * This function allocates all necessary memory for MT slot handling
+ * in the input device, prepares the ABS_MT_SLOT and
+ * ABS_MT_TRACKING_ID events for use and sets up appropriate buffers.
+ * May be called repeatedly. Returns -EINVAL if attempting to
+ * reinitialize with a different number of slots.
+ */
+int input_mt_init_slots(struct input_dev *dev, unsigned int num_slots)
+{
+	int i;
+
+	if (!num_slots)
+		return 0;
+	if (dev->mt)
+		return dev->mtsize != num_slots ? -EINVAL : 0;
+
+	dev->mt = kcalloc(num_slots, sizeof(struct input_mt_slot), GFP_KERNEL);
+	if (!dev->mt)
+		return -ENOMEM;
+
+	dev->mtsize = num_slots;
+	input_set_abs_params(dev, ABS_MT_SLOT, 0, num_slots - 1, 0, 0);
+	input_set_abs_params(dev, ABS_MT_TRACKING_ID, 0, TRKID_MAX, 0, 0);
+	input_set_events_per_packet(dev, 6 * num_slots);
+
+	/* Mark slots as 'unused' */
+	for (i = 0; i < num_slots; i++)
+		input_mt_set_value(&dev->mt[i], ABS_MT_TRACKING_ID, -1);
+
+	return 0;
+}
+EXPORT_SYMBOL(input_mt_init_slots);
+
+/**
+ * input_mt_destroy_slots() - frees the MT slots of the input device
+ * @dev: input device with allocated MT slots
+ *
+ * This function is only needed in error path as the input core will
+ * automatically free the MT slots when the device is destroyed.
+ */
+void input_mt_destroy_slots(struct input_dev *dev)
+{
+	kfree(dev->mt);
+	dev->mt = NULL;
+	dev->mtsize = 0;
+	dev->slot = 0;
+	dev->trkid = 0;
+}
+EXPORT_SYMBOL(input_mt_destroy_slots);
+
+/**
+ * input_mt_report_slot_state() - report contact state
+ * @dev: input device with allocated MT slots
+ * @tool_type: the tool type to use in this slot
+ * @active: true if contact is active, false otherwise
+ *
+ * Reports a contact via ABS_MT_TRACKING_ID, and optionally
+ * ABS_MT_TOOL_TYPE. If active is true and the slot is currently
+ * inactive, or if the tool type is changed, a new tracking id is
+ * assigned to the slot. The tool type is only reported if the
+ * corresponding absbit field is set.
+ */
+void input_mt_report_slot_state(struct input_dev *dev,
+				unsigned int tool_type, bool active)
+{
+	struct input_mt_slot *mt;
+	int id;
+
+	if (!dev->mt || !active) {
+		input_event(dev, EV_ABS, ABS_MT_TRACKING_ID, -1);
+		return;
+	}
+
+	mt = &dev->mt[dev->slot];
+	id = input_mt_get_value(mt, ABS_MT_TRACKING_ID);
+	if (id < 0 || input_mt_get_value(mt, ABS_MT_TOOL_TYPE) != tool_type)
+		id = input_mt_new_trkid(dev);
+
+	input_event(dev, EV_ABS, ABS_MT_TRACKING_ID, id);
+	input_event(dev, EV_ABS, ABS_MT_TOOL_TYPE, tool_type);
+}
+EXPORT_SYMBOL(input_mt_report_slot_state);
+
+/**
+ * input_mt_report_finger_count() - report contact count
+ * @dev: input device with allocated MT slots
+ * @count: the number of contacts
+ *
+ * Reports the contact count via BTN_TOOL_FINGER, BTN_TOOL_DOUBLETAP,
+ * BTN_TOOL_TRIPLETAP and BTN_TOOL_QUADTAP.
+ *
+ * The input core ensures only the KEY events already setup for
+ * this device will produce output.
+ */
+void input_mt_report_finger_count(struct input_dev *dev, int count)
+{
+	input_event(dev, EV_KEY, BTN_TOOL_FINGER, count == 1);
+	input_event(dev, EV_KEY, BTN_TOOL_DOUBLETAP, count == 2);
+	input_event(dev, EV_KEY, BTN_TOOL_TRIPLETAP, count == 3);
+	input_event(dev, EV_KEY, BTN_TOOL_QUADTAP, count == 4);
+}
+EXPORT_SYMBOL(input_mt_report_finger_count);
+
+/**
+ * input_mt_report_pointer_emulation() - common pointer emulation
+ * @dev: input device with allocated MT slots
+ * @use_count: report number of active contacts as finger count
+ *
+ * Performs legacy pointer emulation via BTN_TOUCH, ABS_X, ABS_Y and
+ * ABS_PRESSURE. Touchpad finger count is emulated if use_count is true.
+ *
+ * The input core ensures only the KEY and ABS axes already setup for
+ * this device will produce output.
+ */
+void input_mt_report_pointer_emulation(struct input_dev *dev, bool use_count)
+{
+	struct input_mt_slot *oldest = 0;
+	int oldid = dev->trkid;
+	int count = 0;
+	int i;
+
+	for (i = 0; i < dev->mtsize; ++i) {
+		struct input_mt_slot *ps = &dev->mt[i];
+		int id = input_mt_get_value(ps, ABS_MT_TRACKING_ID);
+
+		if (id < 0)
+			continue;
+		if ((id - oldid) & TRKID_SGN) {
+			oldest = ps;
+			oldid = id;
+		}
+		count++;
+	}
+
+	input_event(dev, EV_KEY, BTN_TOUCH, count > 0);
+	if (use_count)
+		input_mt_report_finger_count(dev, count);
+
+	if (oldest) {
+		int x = input_mt_get_value(oldest, ABS_MT_POSITION_X);
+		int y = input_mt_get_value(oldest, ABS_MT_POSITION_Y);
+		int p = input_mt_get_value(oldest, ABS_MT_PRESSURE);
+
+		input_event(dev, EV_ABS, ABS_X, x);
+		input_event(dev, EV_ABS, ABS_Y, y);
+		input_event(dev, EV_ABS, ABS_PRESSURE, p);
+	}