STRUCT FF_PERIODIC_E(9) Input Subsystem STRUCT FF_PERIODIC_E(9)NAMEstruct_ff_periodic_effect - defines parameters of a periodic
force-feedback effect
SYNOPSIS
struct ff_periodic_effect {
__u16 waveform;
__u16 period;
__s16 magnitude;
__s16 offset;
__u16 phase;
struct ff_envelope envelope;
__u32 custom_len;
__s16 * custom_data;
};
MEMBERS
waveform
kind of the effect (wave)
period
period of the wave (ms)
magnitude
peak value
offset
mean value of the wave (roughly)
phase
´horizontal´ shift
envelope
envelope data
custom_len
number of samples (FF_CUSTOM only)
custom_data
buffer of samples (FF_CUSTOM only)
DESCRIPTION
Known waveforms - FF_SQUARE, FF_TRIANGLE, FF_SINE, FF_SAW_UP,
FF_SAW_DOWN, FF_CUSTOM. The exact syntax FF_CUSTOM is undefined for the
time being as no driver supports it yet.
NOTE
the data pointed by custom_data is copied by the driver. You can
therefore dispose of the memory after the upload/update.
COPYRIGHTKernel Hackers Manual 2.6. November 2013 STRUCT FF_PERIODIC_E(9)