From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kalle Jokiniemi Subject: Re: [PATCH 1/1] input: ff-memless: Allow negative attack / fade ramps Date: Fri, 28 Aug 2015 17:04:21 +0300 Message-ID: <55E06A65.3060001@jolla.com> References: <1440673422-12279-1-git-send-email-kalle.jokiniemi@jolla.com> <1440673422-12279-2-git-send-email-kalle.jokiniemi@jolla.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from smtp96.ord1c.emailsrvr.com ([108.166.43.96]:41527 "EHLO smtp96.ord1c.emailsrvr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752544AbbH1OEX (ORCPT ); Fri, 28 Aug 2015 10:04:23 -0400 In-Reply-To: <1440673422-12279-2-git-send-email-kalle.jokiniemi@jolla.com> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: dmitry.torokhov@gmail.com Cc: linux-input@vger.kernel.org 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: > 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 > --- > 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); >