[2/3] input: mt: Introduce MT event slots (rev 2)

Commit Message

Henrik Rydberg May 1, 2010, 1:55 p.m. UTC

None

Patch

diff --git a/drivers/input/input.c b/drivers/input/input.c
index 187dd8b..6c3fa02 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -162,6 +162,23 @@  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 void input_handle_mt_event(struct input_dev *dev,
+				  unsigned int code, int value)
+{
+	struct input_mt_slot *mtslot = &dev->mt[dev->slot];
+	int oldval = mtslot->absmt[code - ABS_MT_MIN];
+	value = input_defuzz_abs_event(value, oldval, dev->absfuzz[code]);
+	if (value == oldval)
+		return;
+	mtslot->absmt[code - ABS_MT_MIN] = value;
+	dev->sync = 0;
+	if (dev->slot != dev->last_slot) {
+		dev->last_slot = dev->slot;
+		input_pass_event(dev, EV_SYN, SYN_MT_SLOT, dev->slot);
+	}
+	input_pass_event(dev, EV_ABS, code, value);
+}
+
 static void input_handle_event(struct input_dev *dev,
 			       unsigned int type, unsigned int code, int value)
 {
@@ -185,6 +202,10 @@  static void input_handle_event(struct input_dev *dev,
 			dev->sync = 0;
 			disposition = INPUT_PASS_TO_HANDLERS;
 			break;
+		case SYN_MT_SLOT:
+			if (value >= 0 && value < dev->mtsize)
+				dev->slot = value;
+			break;
 		}
 		break;
 
@@ -217,6 +238,10 @@  static void input_handle_event(struct input_dev *dev,
 		if (is_event_supported(code, dev->absbit, ABS_MAX)) {
 
 			if (code >= ABS_MT_MIN && code <= ABS_MT_MAX) {
+				if (dev->mt) {
+					input_handle_mt_event(dev, code, value);
+					return;
+				}
 				disposition = INPUT_PASS_TO_HANDLERS;
 				break;
 			}
@@ -1259,6 +1284,7 @@  static void input_dev_release(struct device *device)
 	struct input_dev *dev = to_input_dev(device);
 
 	input_ff_destroy(dev);
+	input_destroy_mt_slots(dev);
 	kfree(dev);
 
 	module_put(THIS_MODULE);
@@ -1499,6 +1525,43 @@  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
+ * @max_slots: maximum number of slots supported by the device
+ *
+ * This function allocates all necessary memory for MT slot handling
+ * in the input device.
+ */
+int input_create_mt_slots(struct input_dev *dev, int max_slots)
+{
+	struct input_mt_slot *mt;
+
+	mt = kzalloc(max_slots * sizeof(struct input_mt_slot), GFP_KERNEL);
+	if (!mt)
+		return -ENOMEM;
+
+	dev->mt = mt;
+	dev->mtsize = max_slots;
+	return 0;
+}
+EXPORT_SYMBOL(input_create_mt_slots);
+
+/**
+ * input_destroy_mt_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_destroy_mt_slots(struct input_dev *dev)
+{
+	kfree(dev->mt);
+	dev->mt = NULL;
+	dev->mtsize = 0;
+}
+EXPORT_SYMBOL(input_destroy_mt_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...)
diff --git a/include/linux/input.h b/include/linux/input.h
index d4ad53f..0cf1d95 100644
--- a/include/linux/input.h
+++ b/include/linux/input.h
@@ -108,6 +108,7 @@  struct input_absinfo {
 #define SYN_REPORT		0
 #define SYN_CONFIG		1
 #define SYN_MT_REPORT		2
+#define SYN_MT_SLOT		3
 
 /*
  * Keys and buttons
@@ -1083,6 +1084,10 @@  struct ff_effect {
  * @sync: set to 1 when there were no new events since last EV_SYNC
  * @abs: current values for reports from absolute axes
  * @rep: current values for autorepeat parameters (delay, rate)
+ * @mt: array of MT slots
+ * @mtsize: number of allocated MT slots
+ * @slot: current MT slot
+ * @last_slot: last MT slot reported
  * @key: reflects current state of device's keys/buttons
  * @led: reflects current state of device's LEDs
  * @snd: reflects current state of sound effects
@@ -1160,6 +1165,11 @@  struct input_dev {
 	int abs[ABS_MAX + 1];
 	int rep[REP_MAX + 1];
 
+	struct input_mt_slot *mt;
+	int mtsize;
+	int slot;
+	int last_slot;
+
 	unsigned long key[BITS_TO_LONGS(KEY_CNT)];
 	unsigned long led[BITS_TO_LONGS(LED_CNT)];
 	unsigned long snd[BITS_TO_LONGS(SND_CNT)];
@@ -1408,6 +1418,11 @@  static inline void input_mt_sync(struct input_dev *dev)
 	input_event(dev, EV_SYN, SYN_MT_REPORT, 0);
 }
 
+static inline void input_mt_slot(struct input_dev *dev, int slot)
+{
+	input_event(dev, EV_SYN, SYN_MT_SLOT, slot);
+}
+
 void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code);
 
 static inline void input_set_abs_params(struct input_dev *dev, int axis, int min, int max, int fuzz, int flat)
@@ -1487,5 +1502,16 @@  int input_ff_erase(struct input_dev *dev, int effect_id, struct file *file);
 int input_ff_create_memless(struct input_dev *dev, void *data,
 		int (*play_effect)(struct input_dev *, void *, struct ff_effect *));
 
+/**
+ * struct input_mt_slot - represents the state of an MT input slot
+ * @abs: current values from absolute axes for this slot
+ */
+struct input_mt_slot {
+	int absmt[ABS_MT_MAX - ABS_MT_MIN + 1];
+};
+
+int input_create_mt_slots(struct input_dev *dev, int max_slots);
+void input_destroy_mt_slots(struct input_dev *dev);
+
 #endif
 #endif