This adds simple direction calculation to effect
combine. It's useful to decide motor direction for
rumble (vibrator).
Signed-off-by: Jari Vanhala <ext-jari.vanhala@xxxxxxxxx>
---
drivers/input/ff-memless.c | 28 ++++++++++++++++++++++++++++
1 files changed, 28 insertions(+), 0 deletions(-)
diff --git a/drivers/input/ff-memless.c b/drivers/input/ff-memless.c
index 2d1415e..9af009a 100644
--- a/drivers/input/ff-memless.c
+++ b/drivers/input/ff-memless.c
@@ -221,6 +221,14 @@ static int get_compatible_type(struct ff_device *ff, int effect_type)
return 0;
}
+static unsigned int ml_calculate_direction(
+ unsigned int direction, unsigned int force,
+ unsigned int new_direction, unsigned int new_force)
+{
+ return ((u32)direction * force + new_direction * new_force) /
+ (force + new_force);
+}
+
/*
* Combine two effects and apply gain.
*/
@@ -255,6 +263,19 @@ static void ml_combine_effects(struct ff_effect *effect,
case FF_RUMBLE:
strong = new->u.rumble.strong_magnitude * gain / 0xffff;
weak = new->u.rumble.weak_magnitude * gain / 0xffff;
+
+ if (effect->u.rumble.strong_magnitude + strong)
+ effect->direction = ml_calculate_direction(
+ effect->direction,
+ effect->u.rumble.strong_magnitude,
+ new->direction, strong);
+ else if (effect->u.rumble.weak_magnitude + weak)
+ effect->direction = ml_calculate_direction(
+ effect->direction,
+ effect->u.rumble.weak_magnitude,
+ new->direction, weak);
+ else
+ effect->direction = 0;
effect->u.rumble.strong_magnitude =
min(strong + effect->u.rumble.strong_magnitude,
0xffffU);
@@ -269,6 +290,13 @@ static void ml_combine_effects(struct ff_effect *effect,
/* here we also scale it 0x7fff => 0xffff */
i = i * gain / 0x7fff;
+ if (effect->u.rumble.strong_magnitude + i)
+ effect->direction = ml_calculate_direction(
+ effect->direction,
+ effect->u.rumble.strong_magnitude,
+ new->direction, i);
+ else
+ effect->direction = 0;
effect->u.rumble.strong_magnitude =
min(i + effect->u.rumble.strong_magnitude, 0xffffU);
effect->u.rumble.weak_magnitude =
--
1.6.3.3
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