diff options
| -rw-r--r-- | drivers/input/input-mt.c | 32 | ||||
| -rw-r--r-- | include/linux/input/mt.h | 4 |
2 files changed, 36 insertions, 0 deletions
diff --git a/drivers/input/input-mt.c b/drivers/input/input-mt.c index caff298832a4..44f5a67aaa69 100644 --- a/drivers/input/input-mt.c +++ b/drivers/input/input-mt.c @@ -383,3 +383,35 @@ int input_mt_assign_slots(struct input_dev *dev, int *slots, return 0; } EXPORT_SYMBOL(input_mt_assign_slots); + +/** + * input_mt_get_slot_by_key() - return slot matching key + * @dev: input device with allocated MT slots + * @key: the key of the sought slot + * + * Returns the slot of the given key, if it exists, otherwise + * set the key on the first unused slot and return. + * + * If no available slot can be found, -1 is returned. + */ +int input_mt_get_slot_by_key(struct input_dev *dev, int key) +{ + struct input_mt *mt = dev->mt; + struct input_mt_slot *s; + + if (!mt) + return -1; + + for (s = mt->slots; s != mt->slots + mt->num_slots; s++) + if (input_mt_is_active(s) && s->key == key) + return s - mt->slots; + + for (s = mt->slots; s != mt->slots + mt->num_slots; s++) + if (!input_mt_is_active(s)) { + s->key = key; + return s - mt->slots; + } + + return -1; +} +EXPORT_SYMBOL(input_mt_get_slot_by_key); diff --git a/include/linux/input/mt.h b/include/linux/input/mt.h index 6b6f7c8e95bf..cc5cca774bab 100644 --- a/include/linux/input/mt.h +++ b/include/linux/input/mt.h @@ -24,10 +24,12 @@ * struct input_mt_slot - represents the state of an input MT slot * @abs: holds current values of ABS_MT axes for this slot * @frame: last frame at which input_mt_report_slot_state() was called + * @key: optional driver designation of this slot */ struct input_mt_slot { int abs[ABS_MT_LAST - ABS_MT_FIRST + 1]; unsigned int frame; + unsigned int key; }; /** @@ -111,4 +113,6 @@ struct input_mt_pos { int input_mt_assign_slots(struct input_dev *dev, int *slots, const struct input_mt_pos *pos, int num_pos); +int input_mt_get_slot_by_key(struct input_dev *dev, int key); + #endif |