Re: [PATCH 1/1] input: ff-memless: Allow negative attack / fade ramps
From: Kalle Jokiniemi <hidden>
Date: 2015-08-28 14:04:23
Hi, Please disregard this patch, the math doesn't really change with this. I need to dig deeper what really was the issue, as I could see the negative ramp not working. - Kalle On 27.08.2015 14:03, Kalle Jokiniemi wrote:
quoted hunk ↗ jump to hunk
Currently the ff-memless force feedback periodic effects can only have rising attack periods and declining fade periods. E.g. setting a attack ramp that starts high to lower to normal magnitude, will just cause the effect to rumble at high static speed for duration of the attack period and then abruptly lower back to normal magnitude instead of linearly declining the effect during attack phase. To fix this, a check has been added to see if the envelope_level of the attack or fade period is higher than default magnitude or vise versa, and then adjusting the difference value calculation accordingly. Signed-off-by: Kalle Jokiniemi <redacted> --- drivers/input/ff-memless.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)diff --git a/drivers/input/ff-memless.c b/drivers/input/ff-memless.c index 0723e0d..487df7e 100644 --- a/drivers/input/ff-memless.c +++ b/drivers/input/ff-memless.c@@ -190,7 +190,10 @@ static int apply_envelope(struct ml_effect_state *state, int value, } else return value; - difference = abs(value) - envelope_level; + if (abs(value) >= envelope_level) + difference = abs(value) - envelope_level; + else + difference = -(envelope_level - abs(value)); pr_debug("difference = %d\n", difference); pr_debug("time_from_level = 0x%x\n", time_from_level);