1 files changed, 92 insertions, 43 deletions

diff --git a/drivers/input/input.c b/drivers/input/input.c
index a3d5485..54109c3 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -33,25 +33,6 @@ MODULE_LICENSE("GPL");
 
 #define INPUT_DEVICES	256
 
-/*
- * EV_ABS events which should not be cached are listed here.
- */
-static unsigned int input_abs_bypass_init_data[] __initdata = {
-	ABS_MT_TOUCH_MAJOR,
-	ABS_MT_TOUCH_MINOR,
-	ABS_MT_WIDTH_MAJOR,
-	ABS_MT_WIDTH_MINOR,
-	ABS_MT_ORIENTATION,
-	ABS_MT_POSITION_X,
-	ABS_MT_POSITION_Y,
-	ABS_MT_TOOL_TYPE,
-	ABS_MT_BLOB_ID,
-	ABS_MT_TRACKING_ID,
-	ABS_MT_PRESSURE,
-	0
-};
-static unsigned long input_abs_bypass[BITS_TO_LONGS(ABS_CNT)];
-
 static LIST_HEAD(input_dev_list);
 static LIST_HEAD(input_handler_list);
 
@@ -181,6 +162,56 @@ static void input_stop_autorepeat(struct input_dev *dev)
 #define INPUT_PASS_TO_DEVICE	2
 #define INPUT_PASS_TO_ALL	(INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE)
 
+static int input_handle_abs_event(struct input_dev *dev,
+				  unsigned int code, int *pval)
+{
+	bool is_mt_event;
+	int *pold;
+
+	if (code == ABS_MT_SLOT) {
+		/*
+		 * "Stage" the event; we'll flush it later, when we
+		 * get actiual touch data.
+		 */
+		if (*pval >= 0 && *pval < dev->mtsize)
+			dev->slot = *pval;
+
+		return INPUT_IGNORE_EVENT;
+	}
+
+	is_mt_event = code >= ABS_MT_FIRST && code <= ABS_MT_LAST;
+
+	if (!is_mt_event) {
+		pold = &dev->abs[code];
+	} else if (dev->mt) {
+		struct input_mt_slot *mtslot = &dev->mt[dev->slot];
+		pold = &mtslot->abs[code - ABS_MT_FIRST];
+	} else {
+		/*
+		 * Bypass filtering for multitouch events when
+		 * not employing slots.
+		 */
+		pold = NULL;
+	}
+
+	if (pold) {
+		*pval = input_defuzz_abs_event(*pval, *pold,
+						dev->absfuzz[code]);
+		if (*pold == *pval)
+			return INPUT_IGNORE_EVENT;
+
+		*pold = *pval;
+	}
+
+	/* Flush pending "slot" event */
+	if (is_mt_event && dev->slot != dev->abs[ABS_MT_SLOT]) {
+		dev->abs[ABS_MT_SLOT] = dev->slot;
+		input_pass_event(dev, EV_ABS, ABS_MT_SLOT, dev->slot);
+	}
+
+	return INPUT_PASS_TO_HANDLERS;
+}
+
 static void input_handle_event(struct input_dev *dev,
 			       unsigned int type, unsigned int code, int value)
 {
@@ -233,21 +264,9 @@ static void input_handle_event(struct input_dev *dev,
 		break;
 
 	case EV_ABS:
-		if (is_event_supported(code, dev->absbit, ABS_MAX)) {
-
-			if (test_bit(code, input_abs_bypass)) {
-				disposition = INPUT_PASS_TO_HANDLERS;
-				break;
-			}
+		if (is_event_supported(code, dev->absbit, ABS_MAX))
+			disposition = input_handle_abs_event(dev, code, &value);
 
-			value = input_defuzz_abs_event(value,
-					dev->abs[code], dev->absfuzz[code]);
-
-			if (dev->abs[code] != value) {
-				dev->abs[code] = value;
-				disposition = INPUT_PASS_TO_HANDLERS;
-			}
-		}
 		break;
 
 	case EV_REL:
@@ -1288,6 +1307,7 @@ static void input_dev_release(struct device *device)
 	struct input_dev *dev = to_input_dev(device);
 
 	input_ff_destroy(dev);
+	input_mt_destroy_slots(dev);
 	kfree(dev);
 
 	module_put(THIS_MODULE);
@@ -1537,6 +1557,45 @@ void input_free_device(struct input_dev *dev)
 EXPORT_SYMBOL(input_free_device);
 
 /**
+ * input_mt_create_slots() - create 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, and adds ABS_MT_SLOT to the device capabilities.
+ */
+int input_mt_create_slots(struct input_dev *dev, unsigned int num_slots)
+{
+	if (!num_slots)
+		return 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);
+
+	return 0;
+}
+EXPORT_SYMBOL(input_mt_create_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;
+}
+EXPORT_SYMBOL(input_mt_destroy_slots);
+
+/**
  * input_set_capability - mark device as capable of a certain event
  * @dev: device that is capable of emitting or accepting event
  * @type: type of the event (EV_KEY, EV_REL, etc...)
@@ -1945,20 +2004,10 @@ static const struct file_operations input_fops = {
 	.open = input_open_file,
 };
 
-static void __init input_init_abs_bypass(void)
-{
-	const unsigned int *p;
-
-	for (p = input_abs_bypass_init_data; *p; p++)
-		input_abs_bypass[BIT_WORD(*p)] |= BIT_MASK(*p);
-}
-
 static int __init input_init(void)
 {
 	int err;
 
-	input_init_abs_bypass();
-
 	err = class_register(&input_class);
 	if (err) {
 		printk(KERN_ERR "input: unable to register input_dev class\n");