/* * HID driver for N-Trig touchscreens * * Copyright (c) 2008-2010 Rafi Rubin * Copyright (c) 2009-2010 Stephane Chatty * */ /* * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the Free * Software Foundation; either version 2 of the License, or (at your option) * any later version. */ #include #include #include #include "usbhid/usbhid.h" #include #include #include "hid-ids.h" #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; __u16 id; bool tipswitch; bool confidence; bool first_contact_touch; bool reading_mt; __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; }; static ssize_t show_phys_width(struct device *dev, struct device_attribute *attr, char *buf) { struct hid_device *hdev = container_of(dev, struct hid_device, dev); struct ntrig_data *nd = hid_get_drvdata(hdev); return sprintf(buf, "%d\n", nd->sensor_physical_width); } static DEVICE_ATTR(sensor_physical_width, S_IRUGO, show_phys_width, NULL); static ssize_t show_phys_height(struct device *dev, struct device_attribute *attr, char *buf) { struct hid_device *hdev = container_of(dev, struct hid_device, dev); struct ntrig_data *nd = hid_get_drvdata(hdev); return sprintf(buf, "%d\n", nd->sensor_physical_height); } static DEVICE_ATTR(sensor_physical_height, S_IRUGO, show_phys_height, NULL); static ssize_t show_log_width(struct device *dev, struct device_attribute *attr, char *buf) { struct hid_device *hdev = container_of(dev, struct hid_device, dev); struct ntrig_data *nd = hid_get_drvdata(hdev); return sprintf(buf, "%d\n", nd->sensor_logical_width); } static DEVICE_ATTR(sensor_logical_width, S_IRUGO, show_log_width, NULL); static ssize_t show_log_height(struct device *dev, struct device_attribute *attr, char *buf) { struct hid_device *hdev = container_of(dev, struct hid_device, dev); struct ntrig_data *nd = hid_get_drvdata(hdev); return sprintf(buf, "%d\n", nd->sensor_logical_height); } static DEVICE_ATTR(sensor_logical_height, S_IRUGO, show_log_height, NULL); static ssize_t show_min_width(struct device *dev, struct device_attribute *attr, char *buf) { struct hid_device *hdev = container_of(dev, struct hid_device, dev); struct ntrig_data *nd = hid_get_drvdata(hdev); return sprintf(buf, "%d\n", nd->min_width * nd->sensor_physical_width / nd->sensor_logical_width); } static ssize_t set_min_width(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct hid_device *hdev = container_of(dev, struct hid_device, dev); struct ntrig_data *nd = hid_get_drvdata(hdev); unsigned long val; if (strict_strtoul(buf, 0, &val)) return -EINVAL; if (val > nd->sensor_physical_width) return -EINVAL; nd->min_width = val * nd->sensor_logical_width / nd->sensor_physical_width; return count; } static DEVICE_ATTR(min_width, S_IWUSR | S_IRUGO, show_min_width, set_min_width); static ssize_t show_min_height(struct device *dev, struct device_attribute *attr, char *buf) { struct hid_device *hdev = container_of(dev, struct hid_device, dev); struct ntrig_data *nd = hid_get_drvdata(hdev); return sprintf(buf, "%d\n", nd->min_height * nd->sensor_physical_height / nd->sensor_logical_height); } static ssize_t set_min_height(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct hid_device *hdev = container_of(dev, struct hid_device, dev); struct ntrig_data *nd = hid_get_drvdata(hdev); unsigned long val; if (strict_strtoul(buf, 0, &val)) return -EINVAL; if (val > nd->sensor_physical_height) return -EINVAL; nd->min_height = val * nd->sensor_logical_height / nd->sensor_physical_height; return count; } static DEVICE_ATTR(min_height, S_IWUSR | S_IRUGO, show_min_height, set_min_height); static ssize_t show_activate_slack(struct device *dev, struct device_attribute *attr, char *buf) { struct hid_device *hdev = container_of(dev, struct hid_device, dev); struct ntrig_data *nd = hid_get_drvdata(hdev); return sprintf(buf, "%d\n", nd->activate_slack); } static ssize_t set_activate_slack(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct hid_device *hdev = container_of(dev, struct hid_device, dev); struct ntrig_data *nd = hid_get_drvdata(hdev); unsigned long val; if (strict_strtoul(buf, 0, &val)) return -EINVAL; if (val > 0x7f) return -EINVAL; nd->activate_slack = val; return count; } static DEVICE_ATTR(activate_slack, S_IWUSR | S_IRUGO, show_activate_slack, set_activate_slack); static ssize_t show_activation_width(struct device *dev, struct device_attribute *attr, char *buf) { struct hid_device *hdev = container_of(dev, struct hid_device, dev); struct ntrig_data *nd = hid_get_drvdata(hdev); return sprintf(buf, "%d\n", nd->activation_width * nd->sensor_physical_width / nd->sensor_logical_width); } static ssize_t set_activation_width(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct hid_device *hdev = container_of(dev, struct hid_device, dev); struct ntrig_data *nd = hid_get_drvdata(hdev); unsigned long val; if (strict_strtoul(buf, 0, &val)) return -EINVAL; if (val > nd->sensor_physical_width) return -EINVAL; nd->activation_width = val * nd->sensor_logical_width / nd->sensor_physical_width; return count; } static DEVICE_ATTR(activation_width, S_IWUSR | S_IRUGO, show_activation_width, set_activation_width); static ssize_t show_activation_height(struct device *dev, struct device_attribute *attr, char *buf) { struct hid_device *hdev = container_of(dev, struct hid_device, dev); struct ntrig_data *nd = hid_get_drvdata(hdev); return sprintf(buf, "%d\n", nd->activation_height * nd->sensor_physical_height / nd->sensor_logical_height); } static ssize_t set_activation_height(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct hid_device *hdev = container_of(dev, struct hid_device, dev); struct ntrig_data *nd = hid_get_drvdata(hdev); unsigned long val; if (strict_strtoul(buf, 0, &val)) return -EINVAL; if (val > nd->sensor_physical_height) return -EINVAL; nd->activation_height = val * nd->sensor_logical_height / nd->sensor_physical_height; return count; } static DEVICE_ATTR(activation_height, S_IWUSR | S_IRUGO, show_activation_height, set_activation_height); static ssize_t show_deactivate_slack(struct device *dev, struct device_attribute *attr, char *buf) { struct hid_device *hdev = container_of(dev, struct hid_device, dev); struct ntrig_data *nd = hid_get_drvdata(hdev); return sprintf(buf, "%d\n", -nd->deactivate_slack); } static ssize_t set_deactivate_slack(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct hid_device *hdev = container_of(dev, struct hid_device, dev); struct ntrig_data *nd = hid_get_drvdata(hdev); unsigned long val; if (strict_strtoul(buf, 0, &val)) return -EINVAL; /* * No more than 8 terminal frames have been observed so far * and higher slack is highly likely to leave the single * touch emulation stuck down. */ if (val > 7) return -EINVAL; nd->deactivate_slack = -val; return count; } static DEVICE_ATTR(deactivate_slack, S_IWUSR | S_IRUGO, show_deactivate_slack, set_deactivate_slack); static struct attribute *sysfs_attrs[] = { &dev_attr_sensor_physical_width.attr, &dev_attr_sensor_physical_height.attr, &dev_attr_sensor_logical_width.attr, &dev_attr_sensor_logical_height.attr, &dev_attr_min_height.attr, &dev_attr_min_width.attr, &dev_attr_activate_slack.attr, &dev_attr_activation_width.attr, &dev_attr_activation_height.attr, &dev_attr_deactivate_slack.attr, NULL }; static struct attribute_group ntrig_attribute_group = { .attrs = sysfs_attrs }; /* * this driver is aimed at two firmware versions in circulation: * - dual pen/finger single touch * - finger multitouch, pen not working */ 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; switch (usage->hid & HID_USAGE_PAGE) { case HID_UP_GENDESK: switch (usage->hid) { case HID_GD_X: hid_map_usage(hi, usage, bit, max, EV_ABS, ABS_MT_POSITION_X); 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, EV_ABS, ABS_MT_POSITION_Y); 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; case HID_UP_DIGITIZER: switch (usage->hid) { /* we do not want to map these for now */ case HID_DG_CONTACTID: /* Not trustworthy, squelch for now */ case HID_DG_INPUTMODE: case HID_DG_DEVICEINDEX: case HID_DG_CONTACTMAX: return -1; /* width/height mapped on TouchMajor/TouchMinor/Orientation */ case HID_DG_WIDTH: hid_map_usage(hi, usage, bit, max, EV_ABS, ABS_MT_TOUCH_MAJOR); return 1; case HID_DG_HEIGHT: hid_map_usage(hi, usage, bit, max, EV_ABS, ABS_MT_TOUCH_MINOR); input_set_abs_params(hi->input, ABS_MT_ORIENTATION, 0, 1, 0, 0); return 1; } return 0; case 0xff000000: /* we do not want to map these: no input-oriented meaning */ return -1; } return 0; } static int ntrig_input_mapped(struct hid_device *hdev, struct hid_input *hi, struct hid_field *field, struct hid_usage *usage, unsigned long **bit, int *max) { /* No special mappings needed for the pen and single touch */ if (field->physical) return 0; if (usage->type == EV_KEY || usage->type == EV_REL || usage->type == EV_ABS) clear_bit(usage->code, *bit); return 0; } /* * this function is called upon all reports * so that we can filter contact point information, * decide whether we are in multi or single touch mode * and call input_mt_sync after each point if necessary */ static int ntrig_event (struct hid_device *hid, struct hid_field *field, struct hid_usage *usage, __s32 value) { struct input_dev *input = field->hidinput->input; struct ntrig_data *nd = hid_get_drvdata(hid); /* No special handling needed for the pen */ if (field->application == HID_DG_PEN) return 0; if (hid->claimed & HID_CLAIMED_INPUT) { switch (usage->hid) { case 0xff000001: /* Tag indicating the start of a multitouch group */ nd->reading_mt = 1; nd->first_contact_touch = 0; break; case HID_DG_TIPSWITCH: nd->tipswitch = value; /* Prevent emission of touch until validated */ return 1; case HID_DG_CONFIDENCE: nd->confidence = value; break; case HID_GD_X: nd->x = value; /* Clear the contact footer */ nd->mt_foot_count = 0; break; case HID_GD_Y: nd->y = value; break; case HID_DG_CONTACTID: nd->id = value; break; case HID_DG_WIDTH: nd->w = value; break; case HID_DG_HEIGHT: nd->h = value; /* * when in single touch mode, this is the last * report received in a finger event. We want * to emit a normal (X, Y) position */ if (!nd->reading_mt) { /* * TipSwitch indicates the presence of a * finger in single touch mode. */ input_report_key(input, BTN_TOUCH, nd->tipswitch); input_report_key(input, BTN_TOOL_DOUBLETAP, nd->tipswitch); input_event(input, EV_ABS, ABS_X, nd->x); input_event(input, EV_ABS, ABS_Y, nd->y); } break; case 0xff000002: /* * we receive this when the device is in multitouch * mode. The first of the three values tagged with * this usage tells if the contact point is real * or a placeholder */ /* Shouldn't get more than 4 footer packets, so skip */ if (nd->mt_foot_count >= 4) break; nd->mt_footer[nd->mt_foot_count++] = value; /* if the footer isn't complete break */ if (nd->mt_foot_count != 4) break; /* 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; } /* * 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) { /* * TipSwitch is superfluous in multitouch * mode. The footer events tell us * if there is a finger on the screen or * not. */ nd->first_contact_touch = nd->confidence; 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); input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR, nd->w); input_event(input, EV_ABS, ABS_MT_TOUCH_MINOR, nd->h); } else { input_event(input, EV_ABS, ABS_MT_ORIENTATION, 0); input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR, nd->h); input_event(input, EV_ABS, ABS_MT_TOUCH_MINOR, nd->w); } input_mt_sync(field->hidinput->input); break; case HID_DG_CONTACTCOUNT: /* End of a multitouch group */ if (!nd->reading_mt) /* Just to be sure */ break; nd->reading_mt = 0; /* * 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 { input_report_key(input, BTN_TOOL_DOUBLETAP, 0); input_report_key(input, BTN_TOUCH, 0); } break; default: /* fall-back to the generic hidinput handling */ return 0; } } /* we have handled the hidinput part, now remains hiddev */ if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_hid_event) hid->hiddev_hid_event(hid, field, usage, value); return 1; } static int ntrig_probe(struct hid_device *hdev, const struct hid_device_id *id) { int ret; struct ntrig_data *nd; struct hid_input *hidinput; struct input_dev *input; struct hid_report *report; if (id->driver_data) hdev->quirks |= HID_QUIRK_MULTI_INPUT; nd = kmalloc(sizeof(struct ntrig_data), GFP_KERNEL); if (!nd) { dev_err(&hdev->dev, "cannot allocate N-Trig data\n"); return -ENOMEM; } 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); if (ret) { dev_err(&hdev->dev, "parse failed\n"); goto err_free; } ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF); if (ret) { dev_err(&hdev->dev, "hw start failed\n"); goto err_free; } list_for_each_entry(hidinput, &hdev->inputs, list) { if (hidinput->report->maxfield < 1) continue; input = hidinput->input; switch (hidinput->report->field[0]->application) { case HID_DG_PEN: input->name = "N-Trig Pen"; break; case HID_DG_TOUCHSCREEN: /* These keys are redundant for fingers, clear them * to prevent incorrect identification */ __clear_bit(BTN_TOOL_PEN, input->keybit); __clear_bit(BTN_TOOL_FINGER, input->keybit); __clear_bit(BTN_0, input->keybit); __set_bit(BTN_TOOL_DOUBLETAP, input->keybit); /* * The physical touchscreen (single touch) * input has a value for physical, whereas * the multitouch only has logical input * fields. */ input->name = (hidinput->report->field[0] ->physical) ? "N-Trig Touchscreen" : "N-Trig MultiTouch"; break; } } /* This is needed for devices with more recent firmware versions */ report = hdev->report_enum[HID_FEATURE_REPORT].report_id_hash[0x0a]; if (report) usbhid_submit_report(hdev, report, USB_DIR_OUT); ret = sysfs_create_group(&hdev->dev.kobj, &ntrig_attribute_group); return 0; err_free: kfree(nd); return ret; } static void ntrig_remove(struct hid_device *hdev) { sysfs_remove_group(&hdev->dev.kobj, &ntrig_attribute_group); hid_hw_stop(hdev); kfree(hid_get_drvdata(hdev)); } static const struct hid_device_id ntrig_devices[] = { { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN), .driver_data = NTRIG_DUPLICATE_USAGES }, { } }; MODULE_DEVICE_TABLE(hid, ntrig_devices); static const struct hid_usage_id ntrig_grabbed_usages[] = { { HID_ANY_ID, HID_ANY_ID, HID_ANY_ID }, { HID_ANY_ID - 1, HID_ANY_ID - 1, HID_ANY_ID - 1 } }; static struct hid_driver ntrig_driver = { .name = "ntrig", .id_table = ntrig_devices, .probe = ntrig_probe, .remove = ntrig_remove, .input_mapping = ntrig_input_mapping, .input_mapped = ntrig_input_mapped, .usage_table = ntrig_grabbed_usages, .event = ntrig_event, }; static int __init ntrig_init(void) { return hid_register_driver(&ntrig_driver); } static void __exit ntrig_exit(void) { hid_unregister_driver(&ntrig_driver); } module_init(ntrig_init); module_exit(ntrig_exit); MODULE_LICENSE("GPL");