Input: MT - initialize slots to unused

For MT slots, the ABS_MT_TRACKING_ID determines whether a slot is in use,
but currently leaves initialization up to the drivers. This patch sets the
slot state to unused upon creation.

Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
This commit is contained in:
Henrik Rydberg 2010-08-28 21:33:50 -07:00 committed by Dmitry Torokhov
parent 2c4e9671ed
commit ba4d695a90
1 changed files with 9 additions and 2 deletions

View File

@ -1599,11 +1599,14 @@ EXPORT_SYMBOL(input_free_device);
* @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.
* This function allocates all necessary memory for MT slot handling in the
* input device, and adds ABS_MT_SLOT to the device capabilities. All slots
* are initially marked as unused iby setting ABS_MT_TRACKING_ID to -1.
*/
int input_mt_create_slots(struct input_dev *dev, unsigned int num_slots)
{
int i;
if (!num_slots)
return 0;
@ -1614,6 +1617,10 @@ int input_mt_create_slots(struct input_dev *dev, unsigned int num_slots)
dev->mtsize = num_slots;
input_set_abs_params(dev, ABS_MT_SLOT, 0, num_slots - 1, 0, 0);
/* Mark slots as 'unused' */
for (i = 0; i < num_slots; i++)
dev->mt[i].abs[ABS_MT_TRACKING_ID - ABS_MT_FIRST] = -1;
return 0;
}
EXPORT_SYMBOL(input_mt_create_slots);