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STRUCT FF_PERIODIC_E(9) Input Subsystem STRUCT FF_PERIODIC_E(9)

NAME

struct_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 __user * 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.

COPYRIGHT

March 2016 Kernel Hackers Manual 3.2.