v4.19.13 snapshot.
diff --git a/drivers/hid/hid-ntrig.c b/drivers/hid/hid-ntrig.c
new file mode 100644
index 0000000..9bc6f48
--- /dev/null
+++ b/drivers/hid/hid-ntrig.c
@@ -0,0 +1,1036 @@
+/*
+ * 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 <linux/device.h>
+#include <linux/hid.h>
+#include <linux/usb.h>
+#include "usbhid/usbhid.h"
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include "hid-ids.h"
+
+#define NTRIG_DUPLICATE_USAGES 0x001
+
+static unsigned int min_width;
+module_param(min_width, uint, 0644);
+MODULE_PARM_DESC(min_width, "Minimum touch contact width to accept.");
+
+static unsigned int min_height;
+module_param(min_height, uint, 0644);
+MODULE_PARM_DESC(min_height, "Minimum touch contact height to accept.");
+
+static unsigned int activate_slack = 1;
+module_param(activate_slack, uint, 0644);
+MODULE_PARM_DESC(activate_slack, "Number of touch frames to ignore at "
+ "the start of touch input.");
+
+static unsigned int deactivate_slack = 4;
+module_param(deactivate_slack, uint, 0644);
+MODULE_PARM_DESC(deactivate_slack, "Number of empty frames to ignore before "
+ "deactivating touch.");
+
+static unsigned int activation_width = 64;
+module_param(activation_width, uint, 0644);
+MODULE_PARM_DESC(activation_width, "Width threshold to immediately start "
+ "processing touch events.");
+
+static unsigned int activation_height = 32;
+module_param(activation_height, uint, 0644);
+MODULE_PARM_DESC(activation_height, "Height threshold to immediately start "
+ "processing touch events.");
+
+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;
+};
+
+
+/*
+ * This function converts the 4 byte raw firmware code into
+ * a string containing 5 comma separated numbers.
+ */
+static int ntrig_version_string(unsigned char *raw, char *buf)
+{
+ __u8 a = (raw[1] & 0x0e) >> 1;
+ __u8 b = (raw[0] & 0x3c) >> 2;
+ __u8 c = ((raw[0] & 0x03) << 3) | ((raw[3] & 0xe0) >> 5);
+ __u8 d = ((raw[3] & 0x07) << 3) | ((raw[2] & 0xe0) >> 5);
+ __u8 e = raw[2] & 0x07;
+
+ /*
+ * As yet unmapped bits:
+ * 0b11000000 0b11110001 0b00011000 0b00011000
+ */
+
+ return sprintf(buf, "%u.%u.%u.%u.%u", a, b, c, d, e);
+}
+
+static inline int ntrig_get_mode(struct hid_device *hdev)
+{
+ struct hid_report *report = hdev->report_enum[HID_FEATURE_REPORT].
+ report_id_hash[0x0d];
+
+ if (!report || report->maxfield < 1 ||
+ report->field[0]->report_count < 1)
+ return -EINVAL;
+
+ hid_hw_request(hdev, report, HID_REQ_GET_REPORT);
+ hid_hw_wait(hdev);
+ return (int)report->field[0]->value[0];
+}
+
+static inline void ntrig_set_mode(struct hid_device *hdev, const int mode)
+{
+ struct hid_report *report;
+ __u8 mode_commands[4] = { 0xe, 0xf, 0x1b, 0x10 };
+
+ if (mode < 0 || mode > 3)
+ return;
+
+ report = hdev->report_enum[HID_FEATURE_REPORT].
+ report_id_hash[mode_commands[mode]];
+
+ if (!report)
+ return;
+
+ hid_hw_request(hdev, report, HID_REQ_GET_REPORT);
+}
+
+static void ntrig_report_version(struct hid_device *hdev)
+{
+ int ret;
+ char buf[20];
+ struct usb_device *usb_dev = hid_to_usb_dev(hdev);
+ unsigned char *data = kmalloc(8, GFP_KERNEL);
+
+ if (!data)
+ goto err_free;
+
+ ret = usb_control_msg(usb_dev, usb_rcvctrlpipe(usb_dev, 0),
+ USB_REQ_CLEAR_FEATURE,
+ USB_TYPE_CLASS | USB_RECIP_INTERFACE |
+ USB_DIR_IN,
+ 0x30c, 1, data, 8,
+ USB_CTRL_SET_TIMEOUT);
+
+ if (ret == 8) {
+ ret = ntrig_version_string(&data[2], buf);
+
+ hid_info(hdev, "Firmware version: %s (%02x%02x %02x%02x)\n",
+ buf, data[2], data[3], data[4], data[5]);
+ }
+
+err_free:
+ kfree(data);
+}
+
+static ssize_t show_phys_width(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct hid_device *hdev = to_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 = to_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 = to_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 = to_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 = to_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 = to_hid_device(dev);
+ struct ntrig_data *nd = hid_get_drvdata(hdev);
+
+ unsigned long val;
+
+ if (kstrtoul(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 = to_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 = to_hid_device(dev);
+ struct ntrig_data *nd = hid_get_drvdata(hdev);
+
+ unsigned long val;
+
+ if (kstrtoul(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 = to_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 = to_hid_device(dev);
+ struct ntrig_data *nd = hid_get_drvdata(hdev);
+
+ unsigned long val;
+
+ if (kstrtoul(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 = to_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 = to_hid_device(dev);
+ struct ntrig_data *nd = hid_get_drvdata(hdev);
+
+ unsigned long val;
+
+ if (kstrtoul(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 = to_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 = to_hid_device(dev);
+ struct ntrig_data *nd = hid_get_drvdata(hdev);
+
+ unsigned long val;
+
+ if (kstrtoul(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 = to_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 = to_hid_device(dev);
+ struct ntrig_data *nd = hid_get_drvdata(hdev);
+
+ unsigned long val;
+
+ if (kstrtoul(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 const 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 ntrig_data *nd = hid_get_drvdata(hid);
+ struct input_dev *input;
+
+ /* Skip processing if not a claimed input */
+ if (!(hid->claimed & HID_CLAIMED_INPUT))
+ goto not_claimed_input;
+
+ /* This function is being called before the structures are fully
+ * initialized */
+ if(!(field->hidinput && field->hidinput->input))
+ return -EINVAL;
+
+ input = field->hidinput->input;
+
+ /* No special handling needed for the pen */
+ if (field->application == HID_DG_PEN)
+ return 0;
+
+ switch (usage->hid) {
+ case 0xff000001:
+ /* Tag indicating the start of a multitouch group */
+ nd->reading_mt = true;
+ nd->first_contact_touch = false;
+ 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 = false;
+ 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 = false;
+ } 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 = false;
+
+
+ /*
+ * 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;
+ }
+
+not_claimed_input:
+
+ /* 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_input_configured(struct hid_device *hid,
+ struct hid_input *hidinput)
+
+{
+ struct input_dev *input = hidinput->input;
+
+ if (hidinput->report->maxfield < 1)
+ return 0;
+
+ 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;
+ }
+
+ return 0;
+}
+
+static int ntrig_probe(struct hid_device *hdev, const struct hid_device_id *id)
+{
+ int ret;
+ struct ntrig_data *nd;
+ struct hid_report *report;
+
+ if (id->driver_data)
+ hdev->quirks |= HID_QUIRK_MULTI_INPUT
+ | HID_QUIRK_NO_INIT_REPORTS;
+
+ nd = kmalloc(sizeof(struct ntrig_data), GFP_KERNEL);
+ if (!nd) {
+ hid_err(hdev, "cannot allocate N-Trig data\n");
+ return -ENOMEM;
+ }
+
+ nd->reading_mt = false;
+ 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 = 1;
+ nd->sensor_logical_height = 1;
+ nd->sensor_physical_width = 1;
+ nd->sensor_physical_height = 1;
+
+ hid_set_drvdata(hdev, nd);
+
+ ret = hid_parse(hdev);
+ if (ret) {
+ hid_err(hdev, "parse failed\n");
+ goto err_free;
+ }
+
+ ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF);
+ if (ret) {
+ hid_err(hdev, "hw start failed\n");
+ goto err_free;
+ }
+
+ /* This is needed for devices with more recent firmware versions */
+ report = hdev->report_enum[HID_FEATURE_REPORT].report_id_hash[0x0a];
+ if (report) {
+ /* Let the device settle to ensure the wakeup message gets
+ * through */
+ hid_hw_wait(hdev);
+ hid_hw_request(hdev, report, HID_REQ_GET_REPORT);
+
+ /*
+ * Sanity check: if the current mode is invalid reset it to
+ * something reasonable.
+ */
+ if (ntrig_get_mode(hdev) >= 4)
+ ntrig_set_mode(hdev, 3);
+ }
+
+ ntrig_report_version(hdev);
+
+ ret = sysfs_create_group(&hdev->dev.kobj,
+ &ntrig_attribute_group);
+ if (ret)
+ hid_err(hdev, "cannot create sysfs group\n");
+
+ 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 },
+ { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_1),
+ .driver_data = NTRIG_DUPLICATE_USAGES },
+ { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_2),
+ .driver_data = NTRIG_DUPLICATE_USAGES },
+ { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_3),
+ .driver_data = NTRIG_DUPLICATE_USAGES },
+ { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_4),
+ .driver_data = NTRIG_DUPLICATE_USAGES },
+ { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_5),
+ .driver_data = NTRIG_DUPLICATE_USAGES },
+ { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_6),
+ .driver_data = NTRIG_DUPLICATE_USAGES },
+ { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_7),
+ .driver_data = NTRIG_DUPLICATE_USAGES },
+ { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_8),
+ .driver_data = NTRIG_DUPLICATE_USAGES },
+ { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_9),
+ .driver_data = NTRIG_DUPLICATE_USAGES },
+ { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_10),
+ .driver_data = NTRIG_DUPLICATE_USAGES },
+ { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_11),
+ .driver_data = NTRIG_DUPLICATE_USAGES },
+ { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_12),
+ .driver_data = NTRIG_DUPLICATE_USAGES },
+ { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_13),
+ .driver_data = NTRIG_DUPLICATE_USAGES },
+ { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_14),
+ .driver_data = NTRIG_DUPLICATE_USAGES },
+ { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_15),
+ .driver_data = NTRIG_DUPLICATE_USAGES },
+ { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_16),
+ .driver_data = NTRIG_DUPLICATE_USAGES },
+ { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_17),
+ .driver_data = NTRIG_DUPLICATE_USAGES },
+ { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_18),
+ .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,
+ .input_configured = ntrig_input_configured,
+ .usage_table = ntrig_grabbed_usages,
+ .event = ntrig_event,
+};
+module_hid_driver(ntrig_driver);
+
+MODULE_LICENSE("GPL");