[PATCH 2/3] hid-multitouch: Filter collections by application usage.

jeffbrown
2011-07-24T22:07:57Z

From: Jeff Brown <jeffbrown@google.com>

This change fixes two problems.

First, it ensures that the hid-multitouch driver does not incorrectly
map GenericDesktop usages that are intended for other applications,
such as a Mouse.

Second, it sets the appropriate input properties so that user-space
can distinguish TouchScreen devices (INPUT_PROP_DIRECT) from
TouchPad devices (INPUT_PROP_POINTER) and configure them accordingly.

Signed-off-by: jeffbrown@android.com
---
drivers/hid/hid-multitouch.c | 10 ++++++++++
1 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index 58d0e7a..4ee21ac 100644
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -213,6 +213,16 @@ static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi,
struct mt_class *cls = td->mtclass;
__s32 quirks = cls->quirks;

+ /* Only map fields from TouchScreen or TouchPad collections.
+ * We need to ignore fields that belong to other collections
+ * such as Mouse that might have the same GenericDesktop usages. */
+ if (field->application == HID_DG_TOUCHSCREEN)
+ set_bit(INPUT_PROP_DIRECT, hi->input->propbit);
+ else if (field->application == HID_DG_TOUCHPAD)
+ set_bit(INPUT_PROP_POINTER, hi->input->propbit);
+ else
+ return 0;
+
switch (usage->hid & HID_USAGE_PAGE) {

case HID_UP_GENDESK:
--
1.7.0.4