diff options
Diffstat (limited to 'drivers/hid/hid-ntrig.c')
| -rw-r--r-- | drivers/hid/hid-ntrig.c | 220 |
1 files changed, 211 insertions, 9 deletions
diff --git a/drivers/hid/hid-ntrig.c b/drivers/hid/hid-ntrig.c index 4777bbfa1cc2..227d01527c6a 100644 --- a/drivers/hid/hid-ntrig.c +++ b/drivers/hid/hid-ntrig.c @@ -24,6 +24,13 @@ #define NTRIG_DUPLICATE_USAGES 0x001 +static unsigned int min_width; +static unsigned int min_height; +static unsigned int activate_slack = 1; +static unsigned int deactivate_slack = 4; +static unsigned int activation_width = 64; +static unsigned int activation_height = 32; + struct ntrig_data { /* Incoming raw values for a single contact */ __u16 x, y, w, h; @@ -37,6 +44,28 @@ struct ntrig_data { __u8 mt_footer[4]; __u8 mt_foot_count; + + /* The current activation state. */ + __s8 act_state; + + /* Empty frames to ignore before recognizing the end of activity */ + __s8 deactivate_slack; + + /* Frames to ignore before acknowledging the start of activity */ + __s8 activate_slack; + + /* Minimum size contact to accept */ + __u16 min_width; + __u16 min_height; + + /* Threshold to override activation slack */ + __u16 activation_width; + __u16 activation_height; + + __u16 sensor_logical_width; + __u16 sensor_logical_height; + __u16 sensor_physical_width; + __u16 sensor_physical_height; }; /* @@ -49,6 +78,8 @@ static int ntrig_input_mapping(struct hid_device *hdev, struct hid_input *hi, struct hid_field *field, struct hid_usage *usage, unsigned long **bit, int *max) { + struct ntrig_data *nd = hid_get_drvdata(hdev); + /* No special mappings needed for the pen and single touch */ if (field->physical) return 0; @@ -62,6 +93,21 @@ static int ntrig_input_mapping(struct hid_device *hdev, struct hid_input *hi, input_set_abs_params(hi->input, ABS_X, field->logical_minimum, field->logical_maximum, 0, 0); + + if (!nd->sensor_logical_width) { + nd->sensor_logical_width = + field->logical_maximum - + field->logical_minimum; + nd->sensor_physical_width = + field->physical_maximum - + field->physical_minimum; + nd->activation_width = activation_width * + nd->sensor_logical_width / + nd->sensor_physical_width; + nd->min_width = min_width * + nd->sensor_logical_width / + nd->sensor_physical_width; + } return 1; case HID_GD_Y: hid_map_usage(hi, usage, bit, max, @@ -69,6 +115,21 @@ static int ntrig_input_mapping(struct hid_device *hdev, struct hid_input *hi, input_set_abs_params(hi->input, ABS_Y, field->logical_minimum, field->logical_maximum, 0, 0); + + if (!nd->sensor_logical_height) { + nd->sensor_logical_height = + field->logical_maximum - + field->logical_minimum; + nd->sensor_physical_height = + field->physical_maximum - + field->physical_minimum; + nd->activation_height = activation_height * + nd->sensor_logical_height / + nd->sensor_physical_height; + nd->min_height = min_height * + nd->sensor_logical_height / + nd->sensor_physical_height; + } return 1; } return 0; @@ -201,20 +262,68 @@ static int ntrig_event (struct hid_device *hid, struct hid_field *field, if (nd->mt_foot_count != 4) break; - /* Pen activity signal, trigger end of touch. */ + /* Pen activity signal. */ if (nd->mt_footer[2]) { + /* + * When the pen deactivates touch, we see a + * bogus frame with ContactCount > 0. + * We can + * save a bit of work by ensuring act_state < 0 + * even if deactivation slack is turned off. + */ + nd->act_state = deactivate_slack - 1; nd->confidence = 0; break; } - /* If the contact was invalid */ - if (!(nd->confidence && nd->mt_footer[0]) - || nd->w <= 250 - || nd->h <= 190) { - nd->confidence = 0; + /* + * The first footer value indicates the presence of a + * finger. + */ + if (nd->mt_footer[0]) { + /* + * We do not want to process contacts under + * the size threshold, but do not want to + * ignore them for activation state + */ + if (nd->w < nd->min_width || + nd->h < nd->min_height) + nd->confidence = 0; + } else break; + + if (nd->act_state > 0) { + /* + * Contact meets the activation size threshold + */ + if (nd->w >= nd->activation_width && + nd->h >= nd->activation_height) { + if (nd->id) + /* + * first contact, activate now + */ + nd->act_state = 0; + else { + /* + * avoid corrupting this frame + * but ensure next frame will + * be active + */ + nd->act_state = 1; + break; + } + } else + /* + * Defer adjusting the activation state + * until the end of the frame. + */ + break; } + /* Discarding this contact */ + if (!nd->confidence) + break; + /* emit a normal (X, Y) for the first point only */ if (nd->id == 0) { /* @@ -227,8 +336,15 @@ static int ntrig_event (struct hid_device *hid, struct hid_field *field, input_event(input, EV_ABS, ABS_X, nd->x); input_event(input, EV_ABS, ABS_Y, nd->y); } + + /* Emit MT events */ input_event(input, EV_ABS, ABS_MT_POSITION_X, nd->x); input_event(input, EV_ABS, ABS_MT_POSITION_Y, nd->y); + + /* + * Translate from height and width to size + * and orientation. + */ if (nd->w > nd->h) { input_event(input, EV_ABS, ABS_MT_ORIENTATION, 1); @@ -248,12 +364,88 @@ static int ntrig_event (struct hid_device *hid, struct hid_field *field, break; case HID_DG_CONTACTCOUNT: /* End of a multitouch group */ - if (!nd->reading_mt) + if (!nd->reading_mt) /* Just to be sure */ break; nd->reading_mt = 0; - if (nd->first_contact_touch) { + + /* + * Activation state machine logic: + * + * Fundamental states: + * state > 0: Inactive + * state <= 0: Active + * state < -deactivate_slack: + * Pen termination of touch + * + * Specific values of interest + * state == activate_slack + * no valid input since the last reset + * + * state == 0 + * general operational state + * + * state == -deactivate_slack + * read sufficient empty frames to accept + * the end of input and reset + */ + + if (nd->act_state > 0) { /* Currently inactive */ + if (value) + /* + * Consider each live contact as + * evidence of intentional activity. + */ + nd->act_state = (nd->act_state > value) + ? nd->act_state - value + : 0; + else + /* + * Empty frame before we hit the + * activity threshold, reset. + */ + nd->act_state = nd->activate_slack; + + /* + * Entered this block inactive and no + * coordinates sent this frame, so hold off + * on button state. + */ + break; + } else { /* Currently active */ + if (value && nd->act_state >= + nd->deactivate_slack) + /* + * Live point: clear accumulated + * deactivation count. + */ + nd->act_state = 0; + else if (nd->act_state <= nd->deactivate_slack) + /* + * We've consumed the deactivation + * slack, time to deactivate and reset. + */ + nd->act_state = + nd->activate_slack; + else { /* Move towards deactivation */ + nd->act_state--; + break; + } + } + + if (nd->first_contact_touch && nd->act_state <= 0) { + /* + * Check to see if we're ready to start + * emitting touch events. + * + * Note: activation slack will decrease over + * the course of the frame, and it will be + * inconsistent from the start to the end of + * the frame. However if the frame starts + * with slack, first_contact_touch will still + * be 0 and we will not get to this point. + */ input_report_key(input, BTN_TOOL_DOUBLETAP, 1); input_report_key(input, BTN_TOUCH, 1); } else { @@ -263,7 +455,7 @@ static int ntrig_event (struct hid_device *hid, struct hid_field *field, break; default: - /* fallback to the generic hidinput handling */ + /* fall-back to the generic hidinput handling */ return 0; } } @@ -293,6 +485,16 @@ static int ntrig_probe(struct hid_device *hdev, const struct hid_device_id *id) } nd->reading_mt = 0; + nd->min_width = 0; + nd->min_height = 0; + nd->activate_slack = activate_slack; + nd->act_state = activate_slack; + nd->deactivate_slack = -deactivate_slack; + nd->sensor_logical_width = 0; + nd->sensor_logical_height = 0; + nd->sensor_physical_width = 0; + nd->sensor_physical_height = 0; + hid_set_drvdata(hdev, nd); ret = hid_parse(hdev); |