[PATCH v3 10/20] Input: MT - Get slot by key
From: Henrik Rydberg <hidden>
Date: 2012-09-01 19:45:19
Also in:
lkml
Subsystem:
input (keyboard, mouse, joystick, touchscreen) drivers, input multitouch (mt) protocol, the rest · Maintainers:
Dmitry Torokhov, Henrik Rydberg, Linus Torvalds
Some devices use an internal key for tracking which cannot be directly mapped to slots. This patch provides a key-to-slot mapping, which can be used by drivers of such devices. Signed-off-by: Henrik Rydberg <redacted> --- drivers/input/input-mt.c | 32 ++++++++++++++++++++++++++++++++ include/linux/input/mt.h | 4 ++++ 2 files changed, 36 insertions(+)
diff --git a/drivers/input/input-mt.c b/drivers/input/input-mt.c
index 2acf693..4c0e531 100644
--- a/drivers/input/input-mt.c
+++ b/drivers/input/input-mt.c@@ -384,3 +384,35 @@ 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 10bb77c..bbdc694 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; }; /**
@@ -109,4 +111,6 @@ 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
--
1.7.12