Re: [PATCH] Input: ff-core - Correct magnitude setting for rumble compatibility

From: Dmitry Torokhov
Date: Tue Dec 07 2021 - 02:23:30 EST


On Tue, Nov 30, 2021 at 01:50:39PM +0000, Charles Keepax wrote:
> When converting a rumble into a periodic effect, for compatibility,
> the magnitude is effectively calculated using:
>
> magnitude = max(strong_rubble / 3 + weak_rubble / 6, 0x7fff);
>
> The rumble magnitudes are both u16 and the resulting magnitude is
> s16. The max is presumably an attempt to limit the result of the
> calculation to the maximum possible magnitude for the s16 result,
> and thus should be a min.
>
> However in the case of strong = weak = 0xffff, the result of the first
> part of the calculation is 0x7fff, meaning that the min would be
> redundant anyway, so simply remove the current max.
>
> Signed-off-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx>

Applied, thank you.

--
Dmitry