You can specify further configuration by specifying filters that pertain to each touch driver.
To specify a filter, within the mtouch section start a subsection with begin filter and end it with end filter. For example:
begin mtouch driver = focaltech options = generic_j6=1,interrupt=1002,i2c_slave_addr=0x38,i2c_devname=/dev/i2c0,protocol_ver=2 begin mtouch_filter ... type ... options end mtouch_filter end mtouch
Touch filters provide a method of removing unwanted coordinates or coordinate-noise, depending on the filter type that you use. Some filters adjust the coordinate data or suppress them depending on the purpose of the filter. These are the touch filter parameters that are available:
Parameter | Description | Type | Possible value(s) |
---|---|---|---|
type | The series of filters that are applied to the touch coordinates. | String |
|
options |
Filter-specific options. The available filter options depend on the filter type. The format for configuring the filter options is: options= filter_option=value or, if there are multiple options to specify, then separate each option-value pair by a comma: options= filter_option1=value,filter_option2=value |
String |
Based on your filter type, see below for the valid filter options. |
Valid filter options for configuration depend on the filter type. See below for the filter options that are acceptable in the options parameter for the mtouch_filter section (begin mtouch_filter).
Filter option | Description | Default |
---|---|---|
scale | FP scale factor | 256 |
min_gain | Minimal gain | 8 |
low_speed | Low speed threshold | 32 |
These are the options for filter order:
Filter option | Description | Default |
---|---|---|
filter_order | Filter Order | 2 |
These are the options for left edge (e.g., when the x touch coordinate is 0):
Filter option | Description | Default |
---|---|---|
xl_enable | Apply detection | 1 |
xl_bezel | Bezel width | 50 |
xl_speed | Speed threshold | 25 |
xl_jitter | Jitter control | 0 |
xl_reject_physical_bezel | Reject physical bezel | 0 |
These are the options for right edge (e.g., when the x touch coordinate is at the maximum possible value):
Filter option | Description | Default |
---|---|---|
xh_enable | Apply detection | 1 |
xh_bezel | Bezel width | 50 |
xh_speed | Speed threshold | 25 |
xh_jitter | Jitter control | 0 |
xh_reject_physical_bezel | Reject physical bezel | 0 |
These are the options for the top edge (e.g., when the y touch coordinate is 0):
Filter option | Description | Default |
---|---|---|
yl_enable | Apply detection | 1 |
yl_bezel | Bezel width | 80 |
yl_speed | Speed threshold | 25 |
yl_jitter | Jitter control | 0 |
yl_reject_physical_bezel | Reject physical bezel | 0 |
These are the options for the bottom edge (e.g., when the y touch coordinate is at the maximum possible value):
Filter option | Description | Default |
---|---|---|
yh_enable | Apply detection | 1 |
yh_bezel | Bezel width | 50 |
yh_speed | Speed threshold | 25 |
yh_jitter | Jitter control | 0 |
yh_reject_physical_bezel | Reject physical bezel | 0 |
These are the options for Noise variance:
Filter option | Description | Default |
---|---|---|
proc_noise_x_var | Process noise variance (X) | 32 |
proc_noise_y_var | Process noise variance (Y) | 32 |
meas_noise_x_var | Measurement noise variance(X) | 100 |
meas_noise_y_var | Measurement noise variance (Y) | 100 |
These are the options for adaptive speed threshold:
Filter option | Description | Default |
---|---|---|
slot_threshold_1 | Adaptive speed threshold 1 | 30 |
slot_threshold_2 | Adaptive speed threshold 2 | 20 |
slot_threshold_3 | Adaptive speed threshold 3 | 10 |
slot_threshold_4 | Adaptive speed threshold 4 | 5 |