1 files changed, 63 insertions, 6 deletions

diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c
index 4e94ea3e280a..567c3bf64515 100644
--- a/drivers/hid/hid-input.c
+++ b/drivers/hid/hid-input.c
@@ -758,6 +758,11 @@ static void hidinput_configure_usage(struct hid_input *hidinput, struct hid_fiel
 		break;
 
 	case HID_UP_DIGITIZER:
+		if ((field->application & 0xff) == 0x01) /* Digitizer */
+			__set_bit(INPUT_PROP_POINTER, input->propbit);
+		else if ((field->application & 0xff) == 0x02) /* Pen */
+			__set_bit(INPUT_PROP_DIRECT, input->propbit);
+
 		switch (usage->hid & 0xff) {
 		case 0x00: /* Undefined */
 			goto ignore;
@@ -1516,6 +1521,7 @@ static struct hid_input *hidinput_allocate(struct hid_device *hid,
 	struct hid_input *hidinput = kzalloc(sizeof(*hidinput), GFP_KERNEL);
 	struct input_dev *input_dev = input_allocate_device();
 	const char *suffix = NULL;
+	size_t suffix_len, name_len;
 
 	if (!hidinput || !input_dev)
 		goto fail;
@@ -1559,10 +1565,15 @@ static struct hid_input *hidinput_allocate(struct hid_device *hid,
 	}
 
 	if (suffix) {
-		hidinput->name = kasprintf(GFP_KERNEL, "%s %s",
-					   hid->name, suffix);
-		if (!hidinput->name)
-			goto fail;
+		name_len = strlen(hid->name);
+		suffix_len = strlen(suffix);
+		if ((name_len < suffix_len) ||
+		    strcmp(hid->name + name_len - suffix_len, suffix)) {
+			hidinput->name = kasprintf(GFP_KERNEL, "%s %s",
+						   hid->name, suffix);
+			if (!hidinput->name)
+				goto fail;
+		}
 	}
 
 	input_set_drvdata(input_dev, hid);
@@ -1582,6 +1593,7 @@ static struct hid_input *hidinput_allocate(struct hid_device *hid,
 	input_dev->dev.parent = &hid->dev;
 
 	hidinput->input = input_dev;
+	hidinput->application = application;
 	list_add_tail(&hidinput->list, &hid->inputs);
 
 	INIT_LIST_HEAD(&hidinput->reports);
@@ -1677,8 +1689,7 @@ static struct hid_input *hidinput_match_application(struct hid_report *report)
 	struct hid_input *hidinput;
 
 	list_for_each_entry(hidinput, &hid->inputs, list) {
-		if (hidinput->report &&
-		    hidinput->report->application == report->application)
+		if (hidinput->application == report->application)
 			return hidinput;
 	}
 
@@ -1815,6 +1826,7 @@ void hidinput_disconnect(struct hid_device *hid)
 			input_unregister_device(hidinput->input);
 		else
 			input_free_device(hidinput->input);
+		kfree(hidinput->name);
 		kfree(hidinput);
 	}
 
@@ -1826,3 +1838,48 @@ void hidinput_disconnect(struct hid_device *hid)
 }
 EXPORT_SYMBOL_GPL(hidinput_disconnect);
 
+/**
+ * hid_scroll_counter_handle_scroll() - Send high- and low-resolution scroll
+ *                                      events given a high-resolution wheel
+ *                                      movement.
+ * @counter: a hid_scroll_counter struct describing the wheel.
+ * @hi_res_value: the movement of the wheel, in the mouse's high-resolution
+ *                units.
+ *
+ * Given a high-resolution movement, this function converts the movement into
+ * microns and emits high-resolution scroll events for the input device. It also
+ * uses the multiplier from &struct hid_scroll_counter to emit low-resolution
+ * scroll events when appropriate for backwards-compatibility with userspace
+ * input libraries.
+ */
+void hid_scroll_counter_handle_scroll(struct hid_scroll_counter *counter,
+				      int hi_res_value)
+{
+	int low_res_scroll_amount;
+	/* Some wheels will rest 7/8ths of a notch from the previous notch
+	 * after slow movement, so we want the threshold for low-res events to
+	 * be in the middle of the notches (e.g. after 4/8ths) as opposed to on
+	 * the notches themselves (8/8ths).
+	 */
+	int threshold = counter->resolution_multiplier / 2;
+
+	input_report_rel(counter->dev, REL_WHEEL_HI_RES,
+			 hi_res_value * counter->microns_per_hi_res_unit);
+
+	counter->remainder += hi_res_value;
+	if (abs(counter->remainder) >= threshold) {
+		/* Add (or subtract) 1 because we want to trigger when the wheel
+		 * is half-way to the next notch (i.e. scroll 1 notch after a
+		 * 1/2 notch movement, 2 notches after a 1 1/2 notch movement,
+		 * etc.).
+		 */
+		low_res_scroll_amount =
+			counter->remainder / counter->resolution_multiplier
+			+ (hi_res_value > 0 ? 1 : -1);
+		input_report_rel(counter->dev, REL_WHEEL,
+				 low_res_scroll_amount);
+		counter->remainder -=
+			low_res_scroll_amount * counter->resolution_multiplier;
+	}
+}
+EXPORT_SYMBOL_GPL(hid_scroll_counter_handle_scroll);